drivers/md/md.c

   1 /*
   2    md.c : Multiple Devices driver for Linux
   3           Copyright (C) 1998, 1999, 2000 Ingo Molnar
   4
   5      completely rewritten, based on the MD driver code from Marc Zyngier
   6
   7    Changes:
   8
   9    - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
  10    - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
  11    - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
  12    - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
  13    - kmod support by: Cyrus Durgin
  14    - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
  15    - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
  16
  17    - lots of fixes and improvements to the RAID1/RAID5 and generic
  18      RAID code (such as request based resynchronization):
  19
  20      Neil Brown <neilb@cse.unsw.edu.au>.
  21
  22    - persistent bitmap code
  23      Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
  24
  25    This program is free software; you can redistribute it and/or modify
  26    it under the terms of the GNU General Public License as published by
  27    the Free Software Foundation; either version 2, or (at your option)
  28    any later version.
  29
  30    You should have received a copy of the GNU General Public License
  31    (for example /usr/src/linux/COPYING); if not, write to the Free
  32    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  33 */
  34
  35 #include <linux/kthread.h>
  36 #include <linux/blkdev.h>
  37 #include <linux/sysctl.h>
  38 #include <linux/seq_file.h>
  39 #include <linux/fs.h>
  40 #include <linux/poll.h>
  41 #include <linux/ctype.h>
  42 #include <linux/string.h>
  43 #include <linux/hdreg.h>
  44 #include <linux/proc_fs.h>
  45 #include <linux/random.h>
  46 #include <linux/module.h>
  47 #include <linux/reboot.h>
  48 #include <linux/file.h>
  49 #include <linux/compat.h>
  50 #include <linux/delay.h>
  51 #include <linux/raid/md_p.h>
  52 #include <linux/raid/md_u.h>
  53 #include <linux/slab.h>
  54 #include "md.h"
  55 #include "bitmap.h"
  56
  57 #ifndef MODULE
  58 static void autostart_arrays(int part);
  59 #endif
  60
  61 /* pers_list is a list of registered personalities protected
  62  * by pers_lock.
  63  * pers_lock does extra service to protect accesses to
  64  * mddev->thread when the mutex cannot be held.
  65  */
  66 static LIST_HEAD(pers_list);
  67 static DEFINE_SPINLOCK(pers_lock);
  68
  69 static void md_print_devices(void);
  70
  71 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
  72 static struct workqueue_struct *md_wq;
  73 static struct workqueue_struct *md_misc_wq;
  74
  75 #define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
  76
  77 /*
  78  * Default number of read corrections we'll attempt on an rdev
  79  * before ejecting it from the array. We divide the read error
  80  * count by 2 for every hour elapsed between read errors.
  81  */
  82 #define MD_DEFAULT_MAX_CORRECTED_READ_ERRORS 20
  83 /*
  84  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  85  * is 1000 KB/sec, so the extra system load does not show up that much.
  86  * Increase it if you want to have more _guaranteed_ speed. Note that
  87  * the RAID driver will use the maximum available bandwidth if the IO
  88  * subsystem is idle. There is also an 'absolute maximum' reconstruction
  89  * speed limit - in case reconstruction slows down your system despite
  90  * idle IO detection.
  91  *
  92  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  93  * or /sys/block/mdX/md/sync_speed_{min,max}
  94  */
  95
  96 static int sysctl_speed_limit_min = 1000;
  97 static int sysctl_speed_limit_max = 200000;
  98 static inline int speed_min(struct mddev *mddev)
  99 {
 100         return mddev->sync_speed_min ?
 101                 mddev->sync_speed_min : sysctl_speed_limit_min;
 102 }
 103
 104 static inline int speed_max(struct mddev *mddev)
 105 {
 106         return mddev->sync_speed_max ?
 107                 mddev->sync_speed_max : sysctl_speed_limit_max;
 108 }
 109
 110 static struct ctl_table_header *raid_table_header;
 111
 112 static ctl_table raid_table[] = {
 113         {
 114                 .procname       = "speed_limit_min",
 115                 .data           = &sysctl_speed_limit_min,
 116                 .maxlen         = sizeof(int),
 117                 .mode           = S_IRUGO|S_IWUSR,
 118                 .proc_handler   = proc_dointvec,
 119         },
 120         {
 121                 .procname       = "speed_limit_max",
 122                 .data           = &sysctl_speed_limit_max,
 123                 .maxlen         = sizeof(int),
 124                 .mode           = S_IRUGO|S_IWUSR,
 125                 .proc_handler   = proc_dointvec,
 126         },
 127         { }
 128 };
 129
 130 static ctl_table raid_dir_table[] = {
 131         {
 132                 .procname       = "raid",
 133                 .maxlen         = 0,
 134                 .mode           = S_IRUGO|S_IXUGO,
 135                 .child          = raid_table,
 136         },
 137         { }
 138 };
 139
 140 static ctl_table raid_root_table[] = {
 141         {
 142                 .procname       = "dev",
 143                 .maxlen         = 0,
 144                 .mode           = 0555,
 145                 .child          = raid_dir_table,
 146         },
 147         {  }
 148 };
 149
 150 static const struct block_device_operations md_fops;
 151
 152 static int start_readonly;
 153
 154 /* bio_clone_mddev
 155  * like bio_clone, but with a local bio set
 156  */
 157
 158 static void mddev_bio_destructor(struct bio *bio)
 159 {
 160         struct mddev *mddev, **mddevp;
 161
 162         mddevp = (void*)bio;
 163         mddev = mddevp[-1];
 164
 165         bio_free(bio, mddev->bio_set);
 166 }
 167
 168 struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
 169                             struct mddev *mddev)
 170 {
 171         struct bio *b;
 172         struct mddev **mddevp;
 173
 174         if (!mddev || !mddev->bio_set)
 175                 return bio_alloc(gfp_mask, nr_iovecs);
 176
 177         b = bio_alloc_bioset(gfp_mask, nr_iovecs,
 178                              mddev->bio_set);
 179         if (!b)
 180                 return NULL;
 181         mddevp = (void*)b;
 182         mddevp[-1] = mddev;
 183         b->bi_destructor = mddev_bio_destructor;
 184         return b;
 185 }
 186 EXPORT_SYMBOL_GPL(bio_alloc_mddev);
 187
 188 struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask,
 189                             struct mddev *mddev)
 190 {
 191         struct bio *b;
 192         struct mddev **mddevp;
 193
 194         if (!mddev || !mddev->bio_set)
 195                 return bio_clone(bio, gfp_mask);
 196
 197         b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs,
 198                              mddev->bio_set);
 199         if (!b)
 200                 return NULL;
 201         mddevp = (void*)b;
 202         mddevp[-1] = mddev;
 203         b->bi_destructor = mddev_bio_destructor;
 204         __bio_clone(b, bio);
 205         if (bio_integrity(bio)) {
 206                 int ret;
 207
 208                 ret = bio_integrity_clone(b, bio, gfp_mask, mddev->bio_set);
 209
 210                 if (ret < 0) {
 211                         bio_put(b);
 212                         return NULL;
 213                 }
 214         }
 215
 216         return b;
 217 }
 218 EXPORT_SYMBOL_GPL(bio_clone_mddev);
 219
 220 void md_trim_bio(struct bio *bio, int offset, int size)
 221 {
 222         /* 'bio' is a cloned bio which we need to trim to match
 223          * the given offset and size.
 224          * This requires adjusting bi_sector, bi_size, and bi_io_vec
 225          */
 226         int i;
 227         struct bio_vec *bvec;
 228         int sofar = 0;
 229
 230         size <<= 9;
 231         if (offset == 0 && size == bio->bi_size)
 232                 return;
 233
 234         bio->bi_sector += offset;
 235         bio->bi_size = size;
 236         offset <<= 9;
 237         clear_bit(BIO_SEG_VALID, &bio->bi_flags);
 238
 239         while (bio->bi_idx < bio->bi_vcnt &&
 240                bio->bi_io_vec[bio->bi_idx].bv_len <= offset) {
 241                 /* remove this whole bio_vec */
 242                 offset -= bio->bi_io_vec[bio->bi_idx].bv_len;
 243                 bio->bi_idx++;
 244         }
 245         if (bio->bi_idx < bio->bi_vcnt) {
 246                 bio->bi_io_vec[bio->bi_idx].bv_offset += offset;
 247                 bio->bi_io_vec[bio->bi_idx].bv_len -= offset;
 248         }
 249         /* avoid any complications with bi_idx being non-zero*/
 250         if (bio->bi_idx) {
 251                 memmove(bio->bi_io_vec, bio->bi_io_vec+bio->bi_idx,
 252                         (bio->bi_vcnt - bio->bi_idx) * sizeof(struct bio_vec));
 253                 bio->bi_vcnt -= bio->bi_idx;
 254                 bio->bi_idx = 0;
 255         }
 256         /* Make sure vcnt and last bv are not too big */
 257         bio_for_each_segment(bvec, bio, i) {
 258                 if (sofar + bvec->bv_len > size)
 259                         bvec->bv_len = size - sofar;
 260                 if (bvec->bv_len == 0) {
 261                         bio->bi_vcnt = i;
 262                         break;
 263                 }
 264                 sofar += bvec->bv_len;
 265         }
 266 }
 267 EXPORT_SYMBOL_GPL(md_trim_bio);
 268
 269 /*
 270  * We have a system wide 'event count' that is incremented
 271  * on any 'interesting' event, and readers of /proc/mdstat
 272  * can use 'poll' or 'select' to find out when the event
 273  * count increases.
 274  *
 275  * Events are:
 276  *  start array, stop array, error, add device, remove device,
 277  *  start build, activate spare
 278  */
 279 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
 280 static atomic_t md_event_count;
 281 void md_new_event(struct mddev *mddev)
 282 {
 283         atomic_inc(&md_event_count);
 284         wake_up(&md_event_waiters);
 285 }
 286 EXPORT_SYMBOL_GPL(md_new_event);
 287
 288 /* Alternate version that can be called from interrupts
 289  * when calling sysfs_notify isn't needed.
 290  */
 291 static void md_new_event_inintr(struct mddev *mddev)
 292 {
 293         atomic_inc(&md_event_count);
 294         wake_up(&md_event_waiters);
 295 }
 296
 297 /*
 298  * Enables to iterate over all existing md arrays
 299  * all_mddevs_lock protects this list.
 300  */
 301 static LIST_HEAD(all_mddevs);
 302 static DEFINE_SPINLOCK(all_mddevs_lock);
 303
 304
 305 /*
 306  * iterates through all used mddevs in the system.
 307  * We take care to grab the all_mddevs_lock whenever navigating
 308  * the list, and to always hold a refcount when unlocked.
 309  * Any code which breaks out of this loop while own
 310  * a reference to the current mddev and must mddev_put it.
 311  */
 312 #define for_each_mddev(_mddev,_tmp)                                     \
 313                                                                         \
 314         for (({ spin_lock(&all_mddevs_lock);                            \
 315                 _tmp = all_mddevs.next;                                 \
 316                 _mddev = NULL;});                                       \
 317              ({ if (_tmp != &all_mddevs)                                \
 318                         mddev_get(list_entry(_tmp, struct mddev, all_mddevs));\
 319                 spin_unlock(&all_mddevs_lock);                          \
 320                 if (_mddev) mddev_put(_mddev);                          \
 321                 _mddev = list_entry(_tmp, struct mddev, all_mddevs);    \
 322                 _tmp != &all_mddevs;});                                 \
 323              ({ spin_lock(&all_mddevs_lock);                            \
 324                 _tmp = _tmp->next;})                                    \
 325                 )
 326
 327
 328 /* Rather than calling directly into the personality make_request function,
 329  * IO requests come here first so that we can check if the device is
 330  * being suspended pending a reconfiguration.
 331  * We hold a refcount over the call to ->make_request.  By the time that
 332  * call has finished, the bio has been linked into some internal structure
 333  * and so is visible to ->quiesce(), so we don't need the refcount any more.
 334  */
 335 static void md_make_request(struct request_queue *q, struct bio *bio)
 336 {
 337         const int rw = bio_data_dir(bio);
 338         struct mddev *mddev = q->queuedata;
 339         int cpu;
 340         unsigned int sectors;
 341
 342         if (mddev == NULL || mddev->pers == NULL
 343             || !mddev->ready) {
 344                 bio_io_error(bio);
 345                 return;
 346         }
 347         smp_rmb(); /* Ensure implications of  'active' are visible */
 348         rcu_read_lock();
 349         if (mddev->suspended) {
 350                 DEFINE_WAIT(__wait);
 351                 for (;;) {
 352                         prepare_to_wait(&mddev->sb_wait, &__wait,
 353                                         TASK_UNINTERRUPTIBLE);
 354                         if (!mddev->suspended)
 355                                 break;
 356                         rcu_read_unlock();
 357                         schedule();
 358                         rcu_read_lock();
 359                 }
 360                 finish_wait(&mddev->sb_wait, &__wait);
 361         }
 362         atomic_inc(&mddev->active_io);
 363         rcu_read_unlock();
 364
 365         /*
 366          * save the sectors now since our bio can
 367          * go away inside make_request
 368          */
 369         sectors = bio_sectors(bio);
 370         mddev->pers->make_request(mddev, bio);
 371
 372         cpu = part_stat_lock();
 373         part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]);
 374         part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], sectors);
 375         part_stat_unlock();
 376
 377         if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
 378                 wake_up(&mddev->sb_wait);
 379 }
 380
 381 /* mddev_suspend makes sure no new requests are submitted
 382  * to the device, and that any requests that have been submitted
 383  * are completely handled.
 384  * Once ->stop is called and completes, the module will be completely
 385  * unused.
 386  */
 387 void mddev_suspend(struct mddev *mddev)
 388 {
 389         BUG_ON(mddev->suspended);
 390         mddev->suspended = 1;
 391         synchronize_rcu();
 392         wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0);
 393         mddev->pers->quiesce(mddev, 1);
 394
 395         del_timer_sync(&mddev->safemode_timer);
 396 }
 397 EXPORT_SYMBOL_GPL(mddev_suspend);
 398
 399 void mddev_resume(struct mddev *mddev)
 400 {
 401         mddev->suspended = 0;
 402         wake_up(&mddev->sb_wait);
 403         mddev->pers->quiesce(mddev, 0);
 404
 405         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 406         md_wakeup_thread(mddev->thread);
 407         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 408 }
 409 EXPORT_SYMBOL_GPL(mddev_resume);
 410
 411 int mddev_congested(struct mddev *mddev, int bits)
 412 {
 413         return mddev->suspended;
 414 }
 415 EXPORT_SYMBOL(mddev_congested);
 416
 417 /*
 418  * Generic flush handling for md
 419  */
 420
 421 static void md_end_flush(struct bio *bio, int err)
 422 {
 423         struct md_rdev *rdev = bio->bi_private;
 424         struct mddev *mddev = rdev->mddev;
 425
 426         rdev_dec_pending(rdev, mddev);
 427
 428         if (atomic_dec_and_test(&mddev->flush_pending)) {
 429                 /* The pre-request flush has finished */
 430                 queue_work(md_wq, &mddev->flush_work);
 431         }
 432         bio_put(bio);
 433 }
 434
 435 static void md_submit_flush_data(struct work_struct *ws);
 436
 437 static void submit_flushes(struct work_struct *ws)
 438 {
 439         struct mddev *mddev = container_of(ws, struct mddev, flush_work);
 440         struct md_rdev *rdev;
 441
 442         INIT_WORK(&mddev->flush_work, md_submit_flush_data);
 443         atomic_set(&mddev->flush_pending, 1);
 444         rcu_read_lock();
 445         rdev_for_each_rcu(rdev, mddev)
 446                 if (rdev->raid_disk >= 0 &&
 447                     !test_bit(Faulty, &rdev->flags)) {
 448                         /* Take two references, one is dropped
 449                          * when request finishes, one after
 450                          * we reclaim rcu_read_lock
 451                          */
 452                         struct bio *bi;
 453                         atomic_inc(&rdev->nr_pending);
 454                         atomic_inc(&rdev->nr_pending);
 455                         rcu_read_unlock();
 456                         bi = bio_alloc_mddev(GFP_NOIO, 0, mddev);
 457                         bi->bi_end_io = md_end_flush;
 458                         bi->bi_private = rdev;
 459                         bi->bi_bdev = rdev->bdev;
 460                         atomic_inc(&mddev->flush_pending);
 461                         submit_bio(WRITE_FLUSH, bi);
 462                         rcu_read_lock();
 463                         rdev_dec_pending(rdev, mddev);
 464                 }
 465         rcu_read_unlock();
 466         if (atomic_dec_and_test(&mddev->flush_pending))
 467                 queue_work(md_wq, &mddev->flush_work);
 468 }
 469
 470 static void md_submit_flush_data(struct work_struct *ws)
 471 {
 472         struct mddev *mddev = container_of(ws, struct mddev, flush_work);
 473         struct bio *bio = mddev->flush_bio;
 474
 475         if (bio->bi_size == 0)
 476                 /* an empty barrier - all done */
 477                 bio_endio(bio, 0);
 478         else {
 479                 bio->bi_rw &= ~REQ_FLUSH;
 480                 mddev->pers->make_request(mddev, bio);
 481         }
 482
 483         mddev->flush_bio = NULL;
 484         wake_up(&mddev->sb_wait);
 485 }
 486
 487 void md_flush_request(struct mddev *mddev, struct bio *bio)
 488 {
 489         spin_lock_irq(&mddev->write_lock);
 490         wait_event_lock_irq(mddev->sb_wait,
 491                             !mddev->flush_bio,
 492                             mddev->write_lock, /*nothing*/);
 493         mddev->flush_bio = bio;
 494         spin_unlock_irq(&mddev->write_lock);
 495
 496         INIT_WORK(&mddev->flush_work, submit_flushes);
 497         queue_work(md_wq, &mddev->flush_work);
 498 }
 499 EXPORT_SYMBOL(md_flush_request);
 500
 501 /* Support for plugging.
 502  * This mirrors the plugging support in request_queue, but does not
 503  * require having a whole queue or request structures.
 504  * We allocate an md_plug_cb for each md device and each thread it gets
 505  * plugged on.  This links tot the private plug_handle structure in the
 506  * personality data where we keep a count of the number of outstanding
 507  * plugs so other code can see if a plug is active.
 508  */
 509 struct md_plug_cb {
 510         struct blk_plug_cb cb;
 511         struct mddev *mddev;
 512 };
 513
 514 static void plugger_unplug(struct blk_plug_cb *cb)
 515 {
 516         struct md_plug_cb *mdcb = container_of(cb, struct md_plug_cb, cb);
 517         if (atomic_dec_and_test(&mdcb->mddev->plug_cnt))
 518                 md_wakeup_thread(mdcb->mddev->thread);
 519         kfree(mdcb);
 520 }
 521
 522 /* Check that an unplug wakeup will come shortly.
 523  * If not, wakeup the md thread immediately
 524  */
 525 int mddev_check_plugged(struct mddev *mddev)
 526 {
 527         struct blk_plug *plug = current->plug;
 528         struct md_plug_cb *mdcb;
 529
 530         if (!plug)
 531                 return 0;
 532
 533         list_for_each_entry(mdcb, &plug->cb_list, cb.list) {
 534                 if (mdcb->cb.callback == plugger_unplug &&
 535                     mdcb->mddev == mddev) {
 536                         /* Already on the list, move to top */
 537                         if (mdcb != list_first_entry(&plug->cb_list,
 538                                                     struct md_plug_cb,
 539                                                     cb.list))
 540                                 list_move(&mdcb->cb.list, &plug->cb_list);
 541                         return 1;
 542                 }
 543         }
 544         /* Not currently on the callback list */
 545         mdcb = kmalloc(sizeof(*mdcb), GFP_ATOMIC);
 546         if (!mdcb)
 547                 return 0;
 548
 549         mdcb->mddev = mddev;
 550         mdcb->cb.callback = plugger_unplug;
 551         atomic_inc(&mddev->plug_cnt);
 552         list_add(&mdcb->cb.list, &plug->cb_list);
 553         return 1;
 554 }
 555 EXPORT_SYMBOL_GPL(mddev_check_plugged);
 556
 557 static inline struct mddev *mddev_get(struct mddev *mddev)
 558 {
 559         atomic_inc(&mddev->active);
 560         return mddev;
 561 }
 562
 563 static void mddev_delayed_delete(struct work_struct *ws);
 564
 565 static void mddev_put(struct mddev *mddev)
 566 {
 567         struct bio_set *bs = NULL;
 568
 569         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 570                 return;
 571         if (!mddev->raid_disks && list_empty(&mddev->disks) &&
 572             mddev->ctime == 0 && !mddev->hold_active) {
 573                 /* Array is not configured at all, and not held active,
 574                  * so destroy it */
 575                 list_del_init(&mddev->all_mddevs);
 576                 bs = mddev->bio_set;
 577                 mddev->bio_set = NULL;
 578                 if (mddev->gendisk) {
 579                         /* We did a probe so need to clean up.  Call
 580                          * queue_work inside the spinlock so that
 581                          * flush_workqueue() after mddev_find will
 582                          * succeed in waiting for the work to be done.
 583                          */
 584                         INIT_WORK(&mddev->del_work, mddev_delayed_delete);
 585                         queue_work(md_misc_wq, &mddev->del_work);
 586                 } else
 587                         kfree(mddev);
 588         }
 589         spin_unlock(&all_mddevs_lock);
 590         if (bs)
 591                 bioset_free(bs);
 592 }
 593
 594 void mddev_init(struct mddev *mddev)
 595 {
 596         mutex_init(&mddev->open_mutex);
 597         mutex_init(&mddev->reconfig_mutex);
 598         mutex_init(&mddev->bitmap_info.mutex);
 599         INIT_LIST_HEAD(&mddev->disks);
 600         INIT_LIST_HEAD(&mddev->all_mddevs);
 601         init_timer(&mddev->safemode_timer);
 602         atomic_set(&mddev->active, 1);
 603         atomic_set(&mddev->openers, 0);
 604         atomic_set(&mddev->active_io, 0);
 605         atomic_set(&mddev->plug_cnt, 0);
 606         spin_lock_init(&mddev->write_lock);
 607         atomic_set(&mddev->flush_pending, 0);
 608         init_waitqueue_head(&mddev->sb_wait);
 609         init_waitqueue_head(&mddev->recovery_wait);
 610         mddev->reshape_position = MaxSector;
 611         mddev->reshape_backwards = 0;
 612         mddev->resync_min = 0;
 613         mddev->resync_max = MaxSector;
 614         mddev->level = LEVEL_NONE;
 615 }
 616 EXPORT_SYMBOL_GPL(mddev_init);
 617
 618 static struct mddev * mddev_find(dev_t unit)
 619 {
 620         struct mddev *mddev, *new = NULL;
 621
 622         if (unit && MAJOR(unit) != MD_MAJOR)
 623                 unit &= ~((1<<MdpMinorShift)-1);
 624
 625  retry:
 626         spin_lock(&all_mddevs_lock);
 627
 628         if (unit) {
 629                 list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 630                         if (mddev->unit == unit) {
 631                                 mddev_get(mddev);
 632                                 spin_unlock(&all_mddevs_lock);
 633                                 kfree(new);
 634                                 return mddev;
 635                         }
 636
 637                 if (new) {
 638                         list_add(&new->all_mddevs, &all_mddevs);
 639                         spin_unlock(&all_mddevs_lock);
 640                         new->hold_active = UNTIL_IOCTL;
 641                         return new;
 642                 }
 643         } else if (new) {
 644                 /* find an unused unit number */
 645                 static int next_minor = 512;
 646                 int start = next_minor;
 647                 int is_free = 0;
 648                 int dev = 0;
 649                 while (!is_free) {
 650                         dev = MKDEV(MD_MAJOR, next_minor);
 651                         next_minor++;
 652                         if (next_minor > MINORMASK)
 653                                 next_minor = 0;
 654                         if (next_minor == start) {
 655                                 /* Oh dear, all in use. */
 656                                 spin_unlock(&all_mddevs_lock);
 657                                 kfree(new);
 658                                 return NULL;
 659                         }
 660
 661                         is_free = 1;
 662                         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 663                                 if (mddev->unit == dev) {
 664                                         is_free = 0;
 665                                         break;
 666                                 }
 667                 }
 668                 new->unit = dev;
 669                 new->md_minor = MINOR(dev);
 670                 new->hold_active = UNTIL_STOP;
 671                 list_add(&new->all_mddevs, &all_mddevs);
 672                 spin_unlock(&all_mddevs_lock);
 673                 return new;
 674         }
 675         spin_unlock(&all_mddevs_lock);
 676
 677         new = kzalloc(sizeof(*new), GFP_KERNEL);
 678         if (!new)
 679                 return NULL;
 680
 681         new->unit = unit;
 682         if (MAJOR(unit) == MD_MAJOR)
 683                 new->md_minor = MINOR(unit);
 684         else
 685                 new->md_minor = MINOR(unit) >> MdpMinorShift;
 686
 687         mddev_init(new);
 688
 689         goto retry;
 690 }
 691
 692 static inline int mddev_lock(struct mddev * mddev)
 693 {
 694         return mutex_lock_interruptible(&mddev->reconfig_mutex);
 695 }
 696
 697 static inline int mddev_is_locked(struct mddev *mddev)
 698 {
 699         return mutex_is_locked(&mddev->reconfig_mutex);
 700 }
 701
 702 static inline int mddev_trylock(struct mddev * mddev)
 703 {
 704         return mutex_trylock(&mddev->reconfig_mutex);
 705 }
 706
 707 static struct attribute_group md_redundancy_group;
 708
 709 static void mddev_unlock(struct mddev * mddev)
 710 {
 711         if (mddev->to_remove) {
 712                 /* These cannot be removed under reconfig_mutex as
 713                  * an access to the files will try to take reconfig_mutex
 714                  * while holding the file unremovable, which leads to
 715                  * a deadlock.
 716                  * So hold set sysfs_active while the remove in happeing,
 717                  * and anything else which might set ->to_remove or my
 718                  * otherwise change the sysfs namespace will fail with
 719                  * -EBUSY if sysfs_active is still set.
 720                  * We set sysfs_active under reconfig_mutex and elsewhere
 721                  * test it under the same mutex to ensure its correct value
 722                  * is seen.
 723                  */
 724                 struct attribute_group *to_remove = mddev->to_remove;
 725                 mddev->to_remove = NULL;
 726                 mddev->sysfs_active = 1;
 727                 mutex_unlock(&mddev->reconfig_mutex);
 728
 729                 if (mddev->kobj.sd) {
 730                         if (to_remove != &md_redundancy_group)
 731                                 sysfs_remove_group(&mddev->kobj, to_remove);
 732                         if (mddev->pers == NULL ||
 733                             mddev->pers->sync_request == NULL) {
 734                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
 735                                 if (mddev->sysfs_action)
 736                                         sysfs_put(mddev->sysfs_action);
 737                                 mddev->sysfs_action = NULL;
 738                         }
 739                 }
 740                 mddev->sysfs_active = 0;
 741         } else
 742                 mutex_unlock(&mddev->reconfig_mutex);
 743
 744         /* As we've dropped the mutex we need a spinlock to
 745          * make sure the thread doesn't disappear
 746          */
 747         spin_lock(&pers_lock);
 748         md_wakeup_thread(mddev->thread);
 749         spin_unlock(&pers_lock);
 750 }
 751
 752 static struct md_rdev * find_rdev_nr(struct mddev *mddev, int nr)
 753 {
 754         struct md_rdev *rdev;
 755
 756         rdev_for_each(rdev, mddev)
 757                 if (rdev->desc_nr == nr)
 758                         return rdev;
 759
 760         return NULL;
 761 }
 762
 763 static struct md_rdev * find_rdev(struct mddev * mddev, dev_t dev)
 764 {
 765         struct md_rdev *rdev;
 766
 767         rdev_for_each(rdev, mddev)
 768                 if (rdev->bdev->bd_dev == dev)
 769                         return rdev;
 770
 771         return NULL;
 772 }
 773
 774 static struct md_personality *find_pers(int level, char *clevel)
 775 {
 776         struct md_personality *pers;
 777         list_for_each_entry(pers, &pers_list, list) {
 778                 if (level != LEVEL_NONE && pers->level == level)
 779                         return pers;
 780                 if (strcmp(pers->name, clevel)==0)
 781                         return pers;
 782         }
 783         return NULL;
 784 }
 785
 786 /* return the offset of the super block in 512byte sectors */
 787 static inline sector_t calc_dev_sboffset(struct md_rdev *rdev)
 788 {
 789         sector_t num_sectors = i_size_read(rdev->bdev->bd_inode) / 512;
 790         return MD_NEW_SIZE_SECTORS(num_sectors);
 791 }
 792
 793 static int alloc_disk_sb(struct md_rdev * rdev)
 794 {
 795         if (rdev->sb_page)
 796                 MD_BUG();
 797
 798         rdev->sb_page = alloc_page(GFP_KERNEL);
 799         if (!rdev->sb_page) {
 800                 printk(KERN_ALERT "md: out of memory.\n");
 801                 return -ENOMEM;
 802         }
 803
 804         return 0;
 805 }
 806
 807 void md_rdev_clear(struct md_rdev *rdev)
 808 {
 809         if (rdev->sb_page) {
 810                 put_page(rdev->sb_page);
 811                 rdev->sb_loaded = 0;
 812                 rdev->sb_page = NULL;
 813                 rdev->sb_start = 0;
 814                 rdev->sectors = 0;
 815         }
 816         if (rdev->bb_page) {
 817                 put_page(rdev->bb_page);
 818                 rdev->bb_page = NULL;
 819         }
 820         kfree(rdev->badblocks.page);
 821         rdev->badblocks.page = NULL;
 822 }
 823 EXPORT_SYMBOL_GPL(md_rdev_clear);
 824
 825 static void super_written(struct bio *bio, int error)
 826 {
 827         struct md_rdev *rdev = bio->bi_private;
 828         struct mddev *mddev = rdev->mddev;
 829
 830         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags)) {
 831                 printk("md: super_written gets error=%d, uptodate=%d\n",
 832                        error, test_bit(BIO_UPTODATE, &bio->bi_flags));
 833                 WARN_ON(test_bit(BIO_UPTODATE, &bio->bi_flags));
 834                 md_error(mddev, rdev);
 835         }
 836
 837         if (atomic_dec_and_test(&mddev->pending_writes))
 838                 wake_up(&mddev->sb_wait);
 839         bio_put(bio);
 840 }
 841
 842 void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
 843                    sector_t sector, int size, struct page *page)
 844 {
 845         /* write first size bytes of page to sector of rdev
 846          * Increment mddev->pending_writes before returning
 847          * and decrement it on completion, waking up sb_wait
 848          * if zero is reached.
 849          * If an error occurred, call md_error
 850          */
 851         struct bio *bio = bio_alloc_mddev(GFP_NOIO, 1, mddev);
 852
 853         bio->bi_bdev = rdev->meta_bdev ? rdev->meta_bdev : rdev->bdev;
 854         bio->bi_sector = sector;
 855         bio_add_page(bio, page, size, 0);
 856         bio->bi_private = rdev;
 857         bio->bi_end_io = super_written;
 858
 859         atomic_inc(&mddev->pending_writes);
 860         submit_bio(WRITE_FLUSH_FUA, bio);
 861 }
 862
 863 void md_super_wait(struct mddev *mddev)
 864 {
 865         /* wait for all superblock writes that were scheduled to complete */
 866         DEFINE_WAIT(wq);
 867         for(;;) {
 868                 prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
 869                 if (atomic_read(&mddev->pending_writes)==0)
 870                         break;
 871                 schedule();
 872         }
 873         finish_wait(&mddev->sb_wait, &wq);
 874 }
 875
 876 static void bi_complete(struct bio *bio, int error)
 877 {
 878         complete((struct completion*)bio->bi_private);
 879 }
 880
 881 int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
 882                  struct page *page, int rw, bool metadata_op)
 883 {
 884         struct bio *bio = bio_alloc_mddev(GFP_NOIO, 1, rdev->mddev);
 885         struct completion event;
 886         int ret;
 887
 888         rw |= REQ_SYNC;
 889
 890         bio->bi_bdev = (metadata_op && rdev->meta_bdev) ?
 891                 rdev->meta_bdev : rdev->bdev;
 892         if (metadata_op)
 893                 bio->bi_sector = sector + rdev->sb_start;
 894         else if (rdev->mddev->reshape_position != MaxSector &&
 895                  (rdev->mddev->reshape_backwards ==
 896                   (sector >= rdev->mddev->reshape_position)))
 897                 bio->bi_sector = sector + rdev->new_data_offset;
 898         else
 899                 bio->bi_sector = sector + rdev->data_offset;
 900         bio_add_page(bio, page, size, 0);
 901         init_completion(&event);
 902         bio->bi_private = &event;
 903         bio->bi_end_io = bi_complete;
 904         submit_bio(rw, bio);
 905         wait_for_completion(&event);
 906
 907         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 908         bio_put(bio);
 909         return ret;
 910 }
 911 EXPORT_SYMBOL_GPL(sync_page_io);
 912
 913 static int read_disk_sb(struct md_rdev * rdev, int size)
 914 {
 915         char b[BDEVNAME_SIZE];
 916         if (!rdev->sb_page) {
 917                 MD_BUG();
 918                 return -EINVAL;
 919         }
 920         if (rdev->sb_loaded)
 921                 return 0;
 922
 923
 924         if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, true))
 925                 goto fail;
 926         rdev->sb_loaded = 1;
 927         return 0;
 928
 929 fail:
 930         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 931                 bdevname(rdev->bdev,b));
 932         return -EINVAL;
 933 }
 934
 935 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 936 {
 937         return  sb1->set_uuid0 == sb2->set_uuid0 &&
 938                 sb1->set_uuid1 == sb2->set_uuid1 &&
 939                 sb1->set_uuid2 == sb2->set_uuid2 &&
 940                 sb1->set_uuid3 == sb2->set_uuid3;
 941 }
 942
 943 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 944 {
 945         int ret;
 946         mdp_super_t *tmp1, *tmp2;
 947
 948         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 949         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 950
 951         if (!tmp1 || !tmp2) {
 952                 ret = 0;
 953                 printk(KERN_INFO "md.c sb_equal(): failed to allocate memory!\n");
 954                 goto abort;
 955         }
 956
 957         *tmp1 = *sb1;
 958         *tmp2 = *sb2;
 959
 960         /*
 961          * nr_disks is not constant
 962          */
 963         tmp1->nr_disks = 0;
 964         tmp2->nr_disks = 0;
 965
 966         ret = (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4) == 0);
 967 abort:
 968         kfree(tmp1);
 969         kfree(tmp2);
 970         return ret;
 971 }
 972
 973
 974 static u32 md_csum_fold(u32 csum)
 975 {
 976         csum = (csum & 0xffff) + (csum >> 16);
 977         return (csum & 0xffff) + (csum >> 16);
 978 }
 979
 980 static unsigned int calc_sb_csum(mdp_super_t * sb)
 981 {
 982         u64 newcsum = 0;
 983         u32 *sb32 = (u32*)sb;
 984         int i;
 985         unsigned int disk_csum, csum;
 986
 987         disk_csum = sb->sb_csum;
 988         sb->sb_csum = 0;
 989
 990         for (i = 0; i < MD_SB_BYTES/4 ; i++)
 991                 newcsum += sb32[i];
 992         csum = (newcsum & 0xffffffff) + (newcsum>>32);
 993
 994
 995 #ifdef CONFIG_ALPHA
 996         /* This used to use csum_partial, which was wrong for several
 997          * reasons including that different results are returned on
 998          * different architectures.  It isn't critical that we get exactly
 999          * the same return value as before (we always csum_fold before
1000          * testing, and that removes any differences).  However as we
1001          * know that csum_partial always returned a 16bit value on
1002          * alphas, do a fold to maximise conformity to previous behaviour.
1003          */
1004         sb->sb_csum = md_csum_fold(disk_csum);
1005 #else
1006         sb->sb_csum = disk_csum;
1007 #endif
1008         return csum;
1009 }
1010
1011
1012 /*
1013  * Handle superblock details.
1014  * We want to be able to handle multiple superblock formats
1015  * so we have a common interface to them all, and an array of
1016  * different handlers.
1017  * We rely on user-space to write the initial superblock, and support
1018  * reading and updating of superblocks.
1019  * Interface methods are:
1020  *   int load_super(struct md_rdev *dev, struct md_rdev *refdev, int minor_version)
1021  *      loads and validates a superblock on dev.
1022  *      if refdev != NULL, compare superblocks on both devices
1023  *    Return:
1024  *      0 - dev has a superblock that is compatible with refdev
1025  *      1 - dev has a superblock that is compatible and newer than refdev
1026  *          so dev should be used as the refdev in future
1027  *     -EINVAL superblock incompatible or invalid
1028  *     -othererror e.g. -EIO
1029  *
1030  *   int validate_super(struct mddev *mddev, struct md_rdev *dev)
1031  *      Verify that dev is acceptable into mddev.
1032  *       The first time, mddev->raid_disks will be 0, and data from
1033  *       dev should be merged in.  Subsequent calls check that dev
1034  *       is new enough.  Return 0 or -EINVAL
1035  *
1036  *   void sync_super(struct mddev *mddev, struct md_rdev *dev)
1037  *     Update the superblock for rdev with data in mddev
1038  *     This does not write to disc.
1039  *
1040  */
1041
1042 struct super_type  {
1043         char                *name;
1044         struct module       *owner;
1045         int                 (*load_super)(struct md_rdev *rdev,
1046                                           struct md_rdev *refdev,
1047                                           int minor_version);
1048         int                 (*validate_super)(struct mddev *mddev,
1049                                               struct md_rdev *rdev);
1050         void                (*sync_super)(struct mddev *mddev,
1051                                           struct md_rdev *rdev);
1052         unsigned long long  (*rdev_size_change)(struct md_rdev *rdev,
1053                                                 sector_t num_sectors);
1054         int                 (*allow_new_offset)(struct md_rdev *rdev,
1055                                                 unsigned long long new_offset);
1056 };
1057
1058 /*
1059  * Check that the given mddev has no bitmap.
1060  *
1061  * This function is called from the run method of all personalities that do not
1062  * support bitmaps. It prints an error message and returns non-zero if mddev
1063  * has a bitmap. Otherwise, it returns 0.
1064  *
1065  */
1066 int md_check_no_bitmap(struct mddev *mddev)
1067 {
1068         if (!mddev->bitmap_info.file && !mddev->bitmap_info.offset)
1069                 return 0;
1070         printk(KERN_ERR "%s: bitmaps are not supported for %s\n",
1071                 mdname(mddev), mddev->pers->name);
1072         return 1;
1073 }
1074 EXPORT_SYMBOL(md_check_no_bitmap);
1075
1076 /*
1077  * load_super for 0.90.0
1078  */
1079 static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1080 {
1081         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1082         mdp_super_t *sb;
1083         int ret;
1084
1085         /*
1086          * Calculate the position of the superblock (512byte sectors),
1087          * it's at the end of the disk.
1088          *
1089          * It also happens to be a multiple of 4Kb.
1090          */
1091         rdev->sb_start = calc_dev_sboffset(rdev);
1092
1093         ret = read_disk_sb(rdev, MD_SB_BYTES);
1094         if (ret) return ret;
1095
1096         ret = -EINVAL;
1097
1098         bdevname(rdev->bdev, b);
1099         sb = page_address(rdev->sb_page);
1100
1101         if (sb->md_magic != MD_SB_MAGIC) {
1102                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
1103                        b);
1104                 goto abort;
1105         }
1106
1107         if (sb->major_version != 0 ||
1108             sb->minor_version < 90 ||
1109             sb->minor_version > 91) {
1110                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
1111                         sb->major_version, sb->minor_version,
1112                         b);
1113                 goto abort;
1114         }
1115
1116         if (sb->raid_disks <= 0)
1117                 goto abort;
1118
1119         if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
1120                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
1121                         b);
1122                 goto abort;
1123         }
1124
1125         rdev->preferred_minor = sb->md_minor;
1126         rdev->data_offset = 0;
1127         rdev->new_data_offset = 0;
1128         rdev->sb_size = MD_SB_BYTES;
1129         rdev->badblocks.shift = -1;
1130
1131         if (sb->level == LEVEL_MULTIPATH)
1132                 rdev->desc_nr = -1;
1133         else
1134                 rdev->desc_nr = sb->this_disk.number;
1135
1136         if (!refdev) {
1137                 ret = 1;
1138         } else {
1139                 __u64 ev1, ev2;
1140                 mdp_super_t *refsb = page_address(refdev->sb_page);
1141                 if (!uuid_equal(refsb, sb)) {
1142                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
1143                                 b, bdevname(refdev->bdev,b2));
1144                         goto abort;
1145                 }
1146                 if (!sb_equal(refsb, sb)) {
1147                         printk(KERN_WARNING "md: %s has same UUID"
1148                                " but different superblock to %s\n",
1149                                b, bdevname(refdev->bdev, b2));
1150                         goto abort;
1151                 }
1152                 ev1 = md_event(sb);
1153                 ev2 = md_event(refsb);
1154                 if (ev1 > ev2)
1155                         ret = 1;
1156                 else
1157                         ret = 0;
1158         }
1159         rdev->sectors = rdev->sb_start;
1160         /* Limit to 4TB as metadata cannot record more than that */
1161         if (rdev->sectors >= (2ULL << 32))
1162                 rdev->sectors = (2ULL << 32) - 2;
1163
1164         if (rdev->sectors < ((sector_t)sb->size) * 2 && sb->level >= 1)
1165                 /* "this cannot possibly happen" ... */
1166                 ret = -EINVAL;
1167
1168  abort:
1169         return ret;
1170 }
1171
1172 /*
1173  * validate_super for 0.90.0
1174  */
1175 static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
1176 {
1177         mdp_disk_t *desc;
1178         mdp_super_t *sb = page_address(rdev->sb_page);
1179         __u64 ev1 = md_event(sb);
1180
1181         rdev->raid_disk = -1;
1182         clear_bit(Faulty, &rdev->flags);
1183         clear_bit(In_sync, &rdev->flags);
1184         clear_bit(WriteMostly, &rdev->flags);
1185
1186         if (mddev->raid_disks == 0) {
1187                 mddev->major_version = 0;
1188                 mddev->minor_version = sb->minor_version;
1189                 mddev->patch_version = sb->patch_version;
1190                 mddev->external = 0;
1191                 mddev->chunk_sectors = sb->chunk_size >> 9;
1192                 mddev->ctime = sb->ctime;
1193                 mddev->utime = sb->utime;
1194                 mddev->level = sb->level;
1195                 mddev->clevel[0] = 0;
1196                 mddev->layout = sb->layout;
1197                 mddev->raid_disks = sb->raid_disks;
1198                 mddev->dev_sectors = ((sector_t)sb->size) * 2;
1199                 mddev->events = ev1;
1200                 mddev->bitmap_info.offset = 0;
1201                 mddev->bitmap_info.space = 0;
1202                 /* bitmap can use 60 K after the 4K superblocks */
1203                 mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
1204                 mddev->bitmap_info.default_space = 64*2 - (MD_SB_BYTES >> 9);
1205                 mddev->reshape_backwards = 0;
1206
1207                 if (mddev->minor_version >= 91) {
1208                         mddev->reshape_position = sb->reshape_position;
1209                         mddev->delta_disks = sb->delta_disks;
1210                         mddev->new_level = sb->new_level;
1211                         mddev->new_layout = sb->new_layout;
1212                         mddev->new_chunk_sectors = sb->new_chunk >> 9;
1213                         if (mddev->delta_disks < 0)
1214                                 mddev->reshape_backwards = 1;
1215                 } else {
1216                         mddev->reshape_position = MaxSector;
1217                         mddev->delta_disks = 0;
1218                         mddev->new_level = mddev->level;
1219                         mddev->new_layout = mddev->layout;
1220                         mddev->new_chunk_sectors = mddev->chunk_sectors;
1221                 }
1222
1223                 if (sb->state & (1<<MD_SB_CLEAN))
1224                         mddev->recovery_cp = MaxSector;
1225                 else {
1226                         if (sb->events_hi == sb->cp_events_hi &&
1227                                 sb->events_lo == sb->cp_events_lo) {
1228                                 mddev->recovery_cp = sb->recovery_cp;
1229                         } else
1230                                 mddev->recovery_cp = 0;
1231                 }
1232
1233                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
1234                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
1235                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
1236                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
1237
1238                 mddev->max_disks = MD_SB_DISKS;
1239
1240                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
1241                     mddev->bitmap_info.file == NULL) {
1242                         mddev->bitmap_info.offset =
1243                                 mddev->bitmap_info.default_offset;
1244                         mddev->bitmap_info.space =
1245                                 mddev->bitmap_info.space;
1246                 }
1247
1248         } else if (mddev->pers == NULL) {
1249                 /* Insist on good event counter while assembling, except
1250                  * for spares (which don't need an event count) */
1251                 ++ev1;
1252                 if (sb->disks[rdev->desc_nr].state & (
1253                             (1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)))
1254                         if (ev1 < mddev->events)
1255                                 return -EINVAL;
1256         } else if (mddev->bitmap) {
1257                 /* if adding to array with a bitmap, then we can accept an
1258                  * older device ... but not too old.
1259                  */
1260                 if (ev1 < mddev->bitmap->events_cleared)
1261                         return 0;
1262         } else {
1263                 if (ev1 < mddev->events)
1264                         /* just a hot-add of a new device, leave raid_disk at -1 */
1265                         return 0;
1266         }
1267
1268         if (mddev->level != LEVEL_MULTIPATH) {
1269                 desc = sb->disks + rdev->desc_nr;
1270
1271                 if (desc->state & (1<<MD_DISK_FAULTY))
1272                         set_bit(Faulty, &rdev->flags);
1273                 else if (desc->state & (1<<MD_DISK_SYNC) /* &&
1274                             desc->raid_disk < mddev->raid_disks */) {
1275                         set_bit(In_sync, &rdev->flags);
1276                         rdev->raid_disk = desc->raid_disk;
1277                 } else if (desc->state & (1<<MD_DISK_ACTIVE)) {
1278                         /* active but not in sync implies recovery up to
1279                          * reshape position.  We don't know exactly where
1280                          * that is, so set to zero for now */
1281                         if (mddev->minor_version >= 91) {
1282                                 rdev->recovery_offset = 0;
1283                                 rdev->raid_disk = desc->raid_disk;
1284                         }
1285                 }
1286                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
1287                         set_bit(WriteMostly, &rdev->flags);
1288         } else /* MULTIPATH are always insync */
1289                 set_bit(In_sync, &rdev->flags);
1290         return 0;
1291 }
1292
1293 /*
1294  * sync_super for 0.90.0
1295  */
1296 static void super_90_sync(struct mddev *mddev, struct md_rdev *rdev)
1297 {
1298         mdp_super_t *sb;
1299         struct md_rdev *rdev2;
1300         int next_spare = mddev->raid_disks;
1301
1302
1303         /* make rdev->sb match mddev data..
1304          *
1305          * 1/ zero out disks
1306          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
1307          * 3/ any empty disks < next_spare become removed
1308          *
1309          * disks[0] gets initialised to REMOVED because
1310          * we cannot be sure from other fields if it has
1311          * been initialised or not.
1312          */
1313         int i;
1314         int active=0, working=0,failed=0,spare=0,nr_disks=0;
1315
1316         rdev->sb_size = MD_SB_BYTES;
1317
1318         sb = page_address(rdev->sb_page);
1319
1320         memset(sb, 0, sizeof(*sb));
1321
1322         sb->md_magic = MD_SB_MAGIC;
1323         sb->major_version = mddev->major_version;
1324         sb->patch_version = mddev->patch_version;
1325         sb->gvalid_words  = 0; /* ignored */
1326         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
1327         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
1328         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
1329         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
1330
1331         sb->ctime = mddev->ctime;
1332         sb->level = mddev->level;
1333         sb->size = mddev->dev_sectors / 2;
1334         sb->raid_disks = mddev->raid_disks;
1335         sb->md_minor = mddev->md_minor;
1336         sb->not_persistent = 0;
1337         sb->utime = mddev->utime;
1338         sb->state = 0;
1339         sb->events_hi = (mddev->events>>32);
1340         sb->events_lo = (u32)mddev->events;
1341
1342         if (mddev->reshape_position == MaxSector)
1343                 sb->minor_version = 90;
1344         else {
1345                 sb->minor_version = 91;
1346                 sb->reshape_position = mddev->reshape_position;
1347                 sb->new_level = mddev->new_level;
1348                 sb->delta_disks = mddev->delta_disks;
1349                 sb->new_layout = mddev->new_layout;
1350                 sb->new_chunk = mddev->new_chunk_sectors << 9;
1351         }
1352         mddev->minor_version = sb->minor_version;
1353         if (mddev->in_sync)
1354         {
1355                 sb->recovery_cp = mddev->recovery_cp;
1356                 sb->cp_events_hi = (mddev->events>>32);
1357                 sb->cp_events_lo = (u32)mddev->events;
1358                 if (mddev->recovery_cp == MaxSector)
1359                         sb->state = (1<< MD_SB_CLEAN);
1360         } else
1361                 sb->recovery_cp = 0;
1362
1363         sb->layout = mddev->layout;
1364         sb->chunk_size = mddev->chunk_sectors << 9;
1365
1366         if (mddev->bitmap && mddev->bitmap_info.file == NULL)
1367                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
1368
1369         sb->disks[0].state = (1<<MD_DISK_REMOVED);
1370         rdev_for_each(rdev2, mddev) {
1371                 mdp_disk_t *d;
1372                 int desc_nr;
1373                 int is_active = test_bit(In_sync, &rdev2->flags);
1374
1375                 if (rdev2->raid_disk >= 0 &&
1376                     sb->minor_version >= 91)
1377                         /* we have nowhere to store the recovery_offset,
1378                          * but if it is not below the reshape_position,
1379                          * we can piggy-back on that.
1380                          */
1381                         is_active = 1;
1382                 if (rdev2->raid_disk < 0 ||
1383                     test_bit(Faulty, &rdev2->flags))
1384                         is_active = 0;
1385                 if (is_active)
1386                         desc_nr = rdev2->raid_disk;
1387                 else
1388                         desc_nr = next_spare++;
1389                 rdev2->desc_nr = desc_nr;
1390                 d = &sb->disks[rdev2->desc_nr];
1391                 nr_disks++;
1392                 d->number = rdev2->desc_nr;
1393                 d->major = MAJOR(rdev2->bdev->bd_dev);
1394                 d->minor = MINOR(rdev2->bdev->bd_dev);
1395                 if (is_active)
1396                         d->raid_disk = rdev2->raid_disk;
1397                 else
1398                         d->raid_disk = rdev2->desc_nr; /* compatibility */
1399                 if (test_bit(Faulty, &rdev2->flags))
1400                         d->state = (1<<MD_DISK_FAULTY);
1401                 else if (is_active) {
1402                         d->state = (1<<MD_DISK_ACTIVE);
1403                         if (test_bit(In_sync, &rdev2->flags))
1404                                 d->state |= (1<<MD_DISK_SYNC);
1405                         active++;
1406                         working++;
1407                 } else {
1408                         d->state = 0;
1409                         spare++;
1410                         working++;
1411                 }
1412                 if (test_bit(WriteMostly, &rdev2->flags))
1413                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
1414         }
1415         /* now set the "removed" and "faulty" bits on any missing devices */
1416         for (i=0 ; i < mddev->raid_disks ; i++) {
1417                 mdp_disk_t *d = &sb->disks[i];
1418                 if (d->state == 0 && d->number == 0) {
1419                         d->number = i;
1420                         d->raid_disk = i;
1421                         d->state = (1<<MD_DISK_REMOVED);
1422                         d->state |= (1<<MD_DISK_FAULTY);
1423                         failed++;
1424                 }
1425         }
1426         sb->nr_disks = nr_disks;
1427         sb->active_disks = active;
1428         sb->working_disks = working;
1429         sb->failed_disks = failed;
1430         sb->spare_disks = spare;
1431
1432         sb->this_disk = sb->disks[rdev->desc_nr];
1433         sb->sb_csum = calc_sb_csum(sb);
1434 }
1435
1436 /*
1437  * rdev_size_change for 0.90.0
1438  */
1439 static unsigned long long
1440 super_90_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1441 {
1442         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1443                 return 0; /* component must fit device */
1444         if (rdev->mddev->bitmap_info.offset)
1445                 return 0; /* can't move bitmap */
1446         rdev->sb_start = calc_dev_sboffset(rdev);
1447         if (!num_sectors || num_sectors > rdev->sb_start)
1448                 num_sectors = rdev->sb_start;
1449         /* Limit to 4TB as metadata cannot record more than that.
1450          * 4TB == 2^32 KB, or 2*2^32 sectors.
1451          */
1452         if (num_sectors >= (2ULL << 32))
1453                 num_sectors = (2ULL << 32) - 2;
1454         md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1455                        rdev->sb_page);
1456         md_super_wait(rdev->mddev);
1457         return num_sectors;
1458 }
1459
1460 static int
1461 super_90_allow_new_offset(struct md_rdev *rdev, unsigned long long new_offset)
1462 {
1463         /* non-zero offset changes not possible with v0.90 */
1464         return new_offset == 0;
1465 }
1466
1467 /*
1468  * version 1 superblock
1469  */
1470
1471 static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb)
1472 {
1473         __le32 disk_csum;
1474         u32 csum;
1475         unsigned long long newcsum;
1476         int size = 256 + le32_to_cpu(sb->max_dev)*2;
1477         __le32 *isuper = (__le32*)sb;
1478         int i;
1479
1480         disk_csum = sb->sb_csum;
1481         sb->sb_csum = 0;
1482         newcsum = 0;
1483         for (i=0; size>=4; size -= 4 )
1484                 newcsum += le32_to_cpu(*isuper++);
1485
1486         if (size == 2)
1487                 newcsum += le16_to_cpu(*(__le16*) isuper);
1488
1489         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1490         sb->sb_csum = disk_csum;
1491         return cpu_to_le32(csum);
1492 }
1493
1494 static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors,
1495                             int acknowledged);
1496 static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1497 {
1498         struct mdp_superblock_1 *sb;
1499         int ret;
1500         sector_t sb_start;
1501         sector_t sectors;
1502         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1503         int bmask;
1504
1505         /*
1506          * Calculate the position of the superblock in 512byte sectors.
1507          * It is always aligned to a 4K boundary and
1508          * depeding on minor_version, it can be:
1509          * 0: At least 8K, but less than 12K, from end of device
1510          * 1: At start of device
1511          * 2: 4K from start of device.
1512          */
1513         switch(minor_version) {
1514         case 0:
1515                 sb_start = i_size_read(rdev->bdev->bd_inode) >> 9;
1516                 sb_start -= 8*2;
1517                 sb_start &= ~(sector_t)(4*2-1);
1518                 break;
1519         case 1:
1520                 sb_start = 0;
1521                 break;
1522         case 2:
1523                 sb_start = 8;
1524                 break;
1525         default:
1526                 return -EINVAL;
1527         }
1528         rdev->sb_start = sb_start;
1529
1530         /* superblock is rarely larger than 1K, but it can be larger,
1531          * and it is safe to read 4k, so we do that
1532          */
1533         ret = read_disk_sb(rdev, 4096);
1534         if (ret) return ret;
1535
1536
1537         sb = page_address(rdev->sb_page);
1538
1539         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1540             sb->major_version != cpu_to_le32(1) ||
1541             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1542             le64_to_cpu(sb->super_offset) != rdev->sb_start ||
1543             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1544                 return -EINVAL;
1545
1546         if (calc_sb_1_csum(sb) != sb->sb_csum) {
1547                 printk("md: invalid superblock checksum on %s\n",
1548                         bdevname(rdev->bdev,b));
1549                 return -EINVAL;
1550         }
1551         if (le64_to_cpu(sb->data_size) < 10) {
1552                 printk("md: data_size too small on %s\n",
1553                        bdevname(rdev->bdev,b));
1554                 return -EINVAL;
1555         }
1556         if (sb->pad0 ||
1557             sb->pad3[0] ||
1558             memcmp(sb->pad3, sb->pad3+1, sizeof(sb->pad3) - sizeof(sb->pad3[1])))
1559                 /* Some padding is non-zero, might be a new feature */
1560                 return -EINVAL;
1561
1562         rdev->preferred_minor = 0xffff;
1563         rdev->data_offset = le64_to_cpu(sb->data_offset);
1564         rdev->new_data_offset = rdev->data_offset;
1565         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE) &&
1566             (le32_to_cpu(sb->feature_map) & MD_FEATURE_NEW_OFFSET))
1567                 rdev->new_data_offset += (s32)le32_to_cpu(sb->new_offset);
1568         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1569
1570         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1571         bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1572         if (rdev->sb_size & bmask)
1573                 rdev->sb_size = (rdev->sb_size | bmask) + 1;
1574
1575         if (minor_version
1576             && rdev->data_offset < sb_start + (rdev->sb_size/512))
1577                 return -EINVAL;
1578         if (minor_version
1579             && rdev->new_data_offset < sb_start + (rdev->sb_size/512))
1580                 return -EINVAL;
1581
1582         if (sb->level == cpu_to_le32(LEVEL_MULTIPATH))
1583                 rdev->desc_nr = -1;
1584         else
1585                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1586
1587         if (!rdev->bb_page) {
1588                 rdev->bb_page = alloc_page(GFP_KERNEL);
1589                 if (!rdev->bb_page)
1590                         return -ENOMEM;
1591         }
1592         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BAD_BLOCKS) &&
1593             rdev->badblocks.count == 0) {
1594                 /* need to load the bad block list.
1595                  * Currently we limit it to one page.
1596                  */
1597                 s32 offset;
1598                 sector_t bb_sector;
1599                 u64 *bbp;
1600                 int i;
1601                 int sectors = le16_to_cpu(sb->bblog_size);
1602                 if (sectors > (PAGE_SIZE / 512))
1603                         return -EINVAL;
1604                 offset = le32_to_cpu(sb->bblog_offset);
1605                 if (offset == 0)
1606                         return -EINVAL;
1607                 bb_sector = (long long)offset;
1608                 if (!sync_page_io(rdev, bb_sector, sectors << 9,
1609                                   rdev->bb_page, READ, true))
1610                         return -EIO;
1611                 bbp = (u64 *)page_address(rdev->bb_page);
1612                 rdev->badblocks.shift = sb->bblog_shift;
1613                 for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
1614                         u64 bb = le64_to_cpu(*bbp);
1615                         int count = bb & (0x3ff);
1616                         u64 sector = bb >> 10;
1617                         sector <<= sb->bblog_shift;
1618                         count <<= sb->bblog_shift;
1619                         if (bb + 1 == 0)
1620                                 break;
1621                         if (md_set_badblocks(&rdev->badblocks,
1622                                              sector, count, 1) == 0)
1623                                 return -EINVAL;
1624                 }
1625         } else if (sb->bblog_offset == 0)
1626                 rdev->badblocks.shift = -1;
1627
1628         if (!refdev) {
1629                 ret = 1;
1630         } else {
1631                 __u64 ev1, ev2;
1632                 struct mdp_superblock_1 *refsb = page_address(refdev->sb_page);
1633
1634                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1635                     sb->level != refsb->level ||
1636                     sb->layout != refsb->layout ||
1637                     sb->chunksize != refsb->chunksize) {
1638                         printk(KERN_WARNING "md: %s has strangely different"
1639                                 " superblock to %s\n",
1640                                 bdevname(rdev->bdev,b),
1641                                 bdevname(refdev->bdev,b2));
1642                         return -EINVAL;
1643                 }
1644                 ev1 = le64_to_cpu(sb->events);
1645                 ev2 = le64_to_cpu(refsb->events);
1646
1647                 if (ev1 > ev2)
1648                         ret = 1;
1649                 else
1650                         ret = 0;
1651         }
1652         if (minor_version) {
1653                 sectors = (i_size_read(rdev->bdev->bd_inode) >> 9);
1654                 sectors -= rdev->data_offset;
1655         } else
1656                 sectors = rdev->sb_start;
1657         if (sectors < le64_to_cpu(sb->data_size))
1658                 return -EINVAL;
1659         rdev->sectors = le64_to_cpu(sb->data_size);
1660         return ret;
1661 }
1662
1663 static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
1664 {
1665         struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1666         __u64 ev1 = le64_to_cpu(sb->events);
1667
1668         rdev->raid_disk = -1;
1669         clear_bit(Faulty, &rdev->flags);
1670         clear_bit(In_sync, &rdev->flags);
1671         clear_bit(WriteMostly, &rdev->flags);
1672
1673         if (mddev->raid_disks == 0) {
1674                 mddev->major_version = 1;
1675                 mddev->patch_version = 0;
1676                 mddev->external = 0;
1677                 mddev->chunk_sectors = le32_to_cpu(sb->chunksize);
1678                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1679                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1680                 mddev->level = le32_to_cpu(sb->level);
1681                 mddev->clevel[0] = 0;
1682                 mddev->layout = le32_to_cpu(sb->layout);
1683                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1684                 mddev->dev_sectors = le64_to_cpu(sb->size);
1685                 mddev->events = ev1;
1686                 mddev->bitmap_info.offset = 0;
1687                 mddev->bitmap_info.space = 0;
1688                 /* Default location for bitmap is 1K after superblock
1689                  * using 3K - total of 4K
1690                  */
1691                 mddev->bitmap_info.default_offset = 1024 >> 9;
1692                 mddev->bitmap_info.default_space = (4096-1024) >> 9;
1693                 mddev->reshape_backwards = 0;
1694
1695                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1696                 memcpy(mddev->uuid, sb->set_uuid, 16);
1697
1698                 mddev->max_disks =  (4096-256)/2;
1699
1700                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1701                     mddev->bitmap_info.file == NULL) {
1702                         mddev->bitmap_info.offset =
1703                                 (__s32)le32_to_cpu(sb->bitmap_offset);
1704                         /* Metadata doesn't record how much space is available.
1705                          * For 1.0, we assume we can use up to the superblock
1706                          * if before, else to 4K beyond superblock.
1707                          * For others, assume no change is possible.
1708                          */
1709                         if (mddev->minor_version > 0)
1710                                 mddev->bitmap_info.space = 0;
1711                         else if (mddev->bitmap_info.offset > 0)
1712                                 mddev->bitmap_info.space =
1713                                         8 - mddev->bitmap_info.offset;
1714                         else
1715                                 mddev->bitmap_info.space =
1716                                         -mddev->bitmap_info.offset;
1717                 }
1718
1719                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1720                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1721                         mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1722                         mddev->new_level = le32_to_cpu(sb->new_level);
1723                         mddev->new_layout = le32_to_cpu(sb->new_layout);
1724                         mddev->new_chunk_sectors = le32_to_cpu(sb->new_chunk);
1725                         if (mddev->delta_disks < 0 ||
1726                             (mddev->delta_disks == 0 &&
1727                              (le32_to_cpu(sb->feature_map)
1728                               & MD_FEATURE_RESHAPE_BACKWARDS)))
1729                                 mddev->reshape_backwards = 1;
1730                 } else {
1731                         mddev->reshape_position = MaxSector;
1732                         mddev->delta_disks = 0;
1733                         mddev->new_level = mddev->level;
1734                         mddev->new_layout = mddev->layout;
1735                         mddev->new_chunk_sectors = mddev->chunk_sectors;
1736                 }
1737
1738         } else if (mddev->pers == NULL) {
1739                 /* Insist of good event counter while assembling, except for
1740                  * spares (which don't need an event count) */
1741                 ++ev1;
1742                 if (rdev->desc_nr >= 0 &&
1743                     rdev->desc_nr < le32_to_cpu(sb->max_dev) &&
1744                     le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < 0xfffe)
1745                         if (ev1 < mddev->events)
1746                                 return -EINVAL;
1747         } else if (mddev->bitmap) {
1748                 /* If adding to array with a bitmap, then we can accept an
1749                  * older device, but not too old.
1750                  */
1751                 if (ev1 < mddev->bitmap->events_cleared)
1752                         return 0;
1753         } else {
1754                 if (ev1 < mddev->events)
1755                         /* just a hot-add of a new device, leave raid_disk at -1 */
1756                         return 0;
1757         }
1758         if (mddev->level != LEVEL_MULTIPATH) {
1759                 int role;
1760                 if (rdev->desc_nr < 0 ||
1761                     rdev->desc_nr >= le32_to_cpu(sb->max_dev)) {
1762                         role = 0xffff;
1763                         rdev->desc_nr = -1;
1764                 } else
1765                         role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1766                 switch(role) {
1767                 case 0xffff: /* spare */
1768                         break;
1769                 case 0xfffe: /* faulty */
1770                         set_bit(Faulty, &rdev->flags);
1771                         break;
1772                 default:
1773                         if ((le32_to_cpu(sb->feature_map) &
1774                              MD_FEATURE_RECOVERY_OFFSET))
1775                                 rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
1776                         else
1777                                 set_bit(In_sync, &rdev->flags);
1778                         rdev->raid_disk = role;
1779                         break;
1780                 }
1781                 if (sb->devflags & WriteMostly1)
1782                         set_bit(WriteMostly, &rdev->flags);
1783                 if (le32_to_cpu(sb->feature_map) & MD_FEATURE_REPLACEMENT)
1784                         set_bit(Replacement, &rdev->flags);
1785         } else /* MULTIPATH are always insync */
1786                 set_bit(In_sync, &rdev->flags);
1787
1788         return 0;
1789 }
1790
1791 static void super_1_sync(struct mddev *mddev, struct md_rdev *rdev)
1792 {
1793         struct mdp_superblock_1 *sb;
1794         struct md_rdev *rdev2;
1795         int max_dev, i;
1796         /* make rdev->sb match mddev and rdev data. */
1797
1798         sb = page_address(rdev->sb_page);
1799
1800         sb->feature_map = 0;
1801         sb->pad0 = 0;
1802         sb->recovery_offset = cpu_to_le64(0);
1803         memset(sb->pad3, 0, sizeof(sb->pad3));
1804
1805         sb->utime = cpu_to_le64((__u64)mddev->utime);
1806         sb->events = cpu_to_le64(mddev->events);
1807         if (mddev->in_sync)
1808                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1809         else
1810                 sb->resync_offset = cpu_to_le64(0);
1811
1812         sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
1813
1814         sb->raid_disks = cpu_to_le32(mddev->raid_disks);
1815         sb->size = cpu_to_le64(mddev->dev_sectors);
1816         sb->chunksize = cpu_to_le32(mddev->chunk_sectors);
1817         sb->level = cpu_to_le32(mddev->level);
1818         sb->layout = cpu_to_le32(mddev->layout);
1819
1820         if (test_bit(WriteMostly, &rdev->flags))
1821                 sb->devflags |= WriteMostly1;
1822         else
1823                 sb->devflags &= ~WriteMostly1;
1824         sb->data_offset = cpu_to_le64(rdev->data_offset);
1825         sb->data_size = cpu_to_le64(rdev->sectors);
1826
1827         if (mddev->bitmap && mddev->bitmap_info.file == NULL) {
1828                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_info.offset);
1829                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1830         }
1831
1832         if (rdev->raid_disk >= 0 &&
1833             !test_bit(In_sync, &rdev->flags)) {
1834                 sb->feature_map |=
1835                         cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
1836                 sb->recovery_offset =
1837                         cpu_to_le64(rdev->recovery_offset);
1838         }
1839         if (test_bit(Replacement, &rdev->flags))
1840                 sb->feature_map |=
1841                         cpu_to_le32(MD_FEATURE_REPLACEMENT);
1842
1843         if (mddev->reshape_position != MaxSector) {
1844                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1845                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1846                 sb->new_layout = cpu_to_le32(mddev->new_layout);
1847                 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1848                 sb->new_level = cpu_to_le32(mddev->new_level);
1849                 sb->new_chunk = cpu_to_le32(mddev->new_chunk_sectors);
1850                 if (mddev->delta_disks == 0 &&
1851                     mddev->reshape_backwards)
1852                         sb->feature_map
1853                                 |= cpu_to_le32(MD_FEATURE_RESHAPE_BACKWARDS);
1854                 if (rdev->new_data_offset != rdev->data_offset) {
1855                         sb->feature_map
1856                                 |= cpu_to_le32(MD_FEATURE_NEW_OFFSET);
1857                         sb->new_offset = cpu_to_le32((__u32)(rdev->new_data_offset
1858                                                              - rdev->data_offset));
1859                 }
1860         }
1861
1862         if (rdev->badblocks.count == 0)
1863                 /* Nothing to do for bad blocks*/ ;
1864         else if (sb->bblog_offset == 0)
1865                 /* Cannot record bad blocks on this device */
1866                 md_error(mddev, rdev);
1867         else {
1868                 struct badblocks *bb = &rdev->badblocks;
1869                 u64 *bbp = (u64 *)page_address(rdev->bb_page);
1870                 u64 *p = bb->page;
1871                 sb->feature_map |= cpu_to_le32(MD_FEATURE_BAD_BLOCKS);
1872                 if (bb->changed) {
1873                         unsigned seq;
1874
1875 retry:
1876                         seq = read_seqbegin(&bb->lock);
1877
1878                         memset(bbp, 0xff, PAGE_SIZE);
1879
1880                         for (i = 0 ; i < bb->count ; i++) {
1881                                 u64 internal_bb = *p++;
1882                                 u64 store_bb = ((BB_OFFSET(internal_bb) << 10)
1883                                                 | BB_LEN(internal_bb));
1884                                 *bbp++ = cpu_to_le64(store_bb);
1885                         }
1886                         bb->changed = 0;
1887                         if (read_seqretry(&bb->lock, seq))
1888                                 goto retry;
1889
1890                         bb->sector = (rdev->sb_start +
1891                                       (int)le32_to_cpu(sb->bblog_offset));
1892                         bb->size = le16_to_cpu(sb->bblog_size);
1893                 }
1894         }
1895
1896         max_dev = 0;
1897         rdev_for_each(rdev2, mddev)
1898                 if (rdev2->desc_nr+1 > max_dev)
1899                         max_dev = rdev2->desc_nr+1;
1900
1901         if (max_dev > le32_to_cpu(sb->max_dev)) {
1902                 int bmask;
1903                 sb->max_dev = cpu_to_le32(max_dev);
1904                 rdev->sb_size = max_dev * 2 + 256;
1905                 bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1906                 if (rdev->sb_size & bmask)
1907                         rdev->sb_size = (rdev->sb_size | bmask) + 1;
1908         } else
1909                 max_dev = le32_to_cpu(sb->max_dev);
1910
1911         for (i=0; i<max_dev;i++)
1912                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1913
1914         rdev_for_each(rdev2, mddev) {
1915                 i = rdev2->desc_nr;
1916                 if (test_bit(Faulty, &rdev2->flags))
1917                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1918                 else if (test_bit(In_sync, &rdev2->flags))
1919                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1920                 else if (rdev2->raid_disk >= 0)
1921                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1922                 else
1923                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1924         }
1925
1926         sb->sb_csum = calc_sb_1_csum(sb);
1927 }
1928
1929 static unsigned long long
1930 super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1931 {
1932         struct mdp_superblock_1 *sb;
1933         sector_t max_sectors;
1934         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1935                 return 0; /* component must fit device */
1936         if (rdev->data_offset != rdev->new_data_offset)
1937                 return 0; /* too confusing */
1938         if (rdev->sb_start < rdev->data_offset) {
1939                 /* minor versions 1 and 2; superblock before data */
1940                 max_sectors = i_size_read(rdev->bdev->bd_inode) >> 9;
1941                 max_sectors -= rdev->data_offset;
1942                 if (!num_sectors || num_sectors > max_sectors)
1943                         num_sectors = max_sectors;
1944         } else if (rdev->mddev->bitmap_info.offset) {
1945                 /* minor version 0 with bitmap we can't move */
1946                 return 0;
1947         } else {
1948                 /* minor version 0; superblock after data */
1949                 sector_t sb_start;
1950                 sb_start = (i_size_read(rdev->bdev->bd_inode) >> 9) - 8*2;
1951                 sb_start &= ~(sector_t)(4*2 - 1);
1952                 max_sectors = rdev->sectors + sb_start - rdev->sb_start;
1953                 if (!num_sectors || num_sectors > max_sectors)
1954                         num_sectors = max_sectors;
1955                 rdev->sb_start = sb_start;
1956         }
1957         sb = page_address(rdev->sb_page);
1958         sb->data_size = cpu_to_le64(num_sectors);
1959         sb->super_offset = rdev->sb_start;
1960         sb->sb_csum = calc_sb_1_csum(sb);
1961         md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1962                        rdev->sb_page);
1963         md_super_wait(rdev->mddev);
1964         return num_sectors;
1965
1966 }
1967
1968 static int
1969 super_1_allow_new_offset(struct md_rdev *rdev,
1970                          unsigned long long new_offset)
1971 {
1972         /* All necessary checks on new >= old have been done */
1973         struct bitmap *bitmap;
1974         if (new_offset >= rdev->data_offset)
1975                 return 1;
1976
1977         /* with 1.0 metadata, there is no metadata to tread on
1978          * so we can always move back */
1979         if (rdev->mddev->minor_version == 0)
1980                 return 1;
1981
1982         /* otherwise we must be sure not to step on
1983          * any metadata, so stay:
1984          * 36K beyond start of superblock
1985          * beyond end of badblocks
1986          * beyond write-intent bitmap
1987          */
1988         if (rdev->sb_start + (32+4)*2 > new_offset)
1989                 return 0;
1990         bitmap = rdev->mddev->bitmap;
1991         if (bitmap && !rdev->mddev->bitmap_info.file &&
1992             rdev->sb_start + rdev->mddev->bitmap_info.offset +
1993             bitmap->storage.file_pages * (PAGE_SIZE>>9) > new_offset)
1994                 return 0;
1995         if (rdev->badblocks.sector + rdev->badblocks.size > new_offset)
1996                 return 0;
1997
1998         return 1;
1999 }
2000
2001 static struct super_type super_types[] = {
2002         [0] = {
2003                 .name   = "0.90.0",
2004                 .owner  = THIS_MODULE,
2005                 .load_super         = super_90_load,
2006                 .validate_super     = super_90_validate,
2007                 .sync_super         = super_90_sync,
2008                 .rdev_size_change   = super_90_rdev_size_change,
2009                 .allow_new_offset   = super_90_allow_new_offset,
2010         },
2011         [1] = {
2012                 .name   = "md-1",
2013                 .owner  = THIS_MODULE,
2014                 .load_super         = super_1_load,
2015                 .validate_super     = super_1_validate,
2016                 .sync_super         = super_1_sync,
2017                 .rdev_size_change   = super_1_rdev_size_change,
2018                 .allow_new_offset   = super_1_allow_new_offset,
2019         },
2020 };
2021
2022 static void sync_super(struct mddev *mddev, struct md_rdev *rdev)
2023 {
2024         if (mddev->sync_super) {
2025                 mddev->sync_super(mddev, rdev);
2026                 return;
2027         }
2028
2029         BUG_ON(mddev->major_version >= ARRAY_SIZE(super_types));
2030
2031         super_types[mddev->major_version].sync_super(mddev, rdev);
2032 }
2033
2034 static int match_mddev_units(struct mddev *mddev1, struct mddev *mddev2)
2035 {
2036         struct md_rdev *rdev, *rdev2;
2037
2038         rcu_read_lock();
2039         rdev_for_each_rcu(rdev, mddev1)
2040                 rdev_for_each_rcu(rdev2, mddev2)
2041                         if (rdev->bdev->bd_contains ==
2042                             rdev2->bdev->bd_contains) {
2043                                 rcu_read_unlock();
2044                                 return 1;
2045                         }
2046         rcu_read_unlock();
2047         return 0;
2048 }
2049
2050 static LIST_HEAD(pending_raid_disks);
2051
2052 /*
2053  * Try to register data integrity profile for an mddev
2054  *
2055  * This is called when an array is started and after a disk has been kicked
2056  * from the array. It only succeeds if all working and active component devices
2057  * are integrity capable with matching profiles.
2058  */
2059 int md_integrity_register(struct mddev *mddev)
2060 {
2061         struct md_rdev *rdev, *reference = NULL;
2062
2063         if (list_empty(&mddev->disks))
2064                 return 0; /* nothing to do */
2065         if (!mddev->gendisk || blk_get_integrity(mddev->gendisk))
2066                 return 0; /* shouldn't register, or already is */
2067         rdev_for_each(rdev, mddev) {
2068                 /* skip spares and non-functional disks */
2069                 if (test_bit(Faulty, &rdev->flags))
2070                         continue;
2071                 if (rdev->raid_disk < 0)
2072                         continue;
2073                 if (!reference) {
2074                         /* Use the first rdev as the reference */
2075                         reference = rdev;
2076                         continue;
2077                 }
2078                 /* does this rdev's profile match the reference profile? */
2079                 if (blk_integrity_compare(reference->bdev->bd_disk,
2080                                 rdev->bdev->bd_disk) < 0)
2081                         return -EINVAL;
2082         }
2083         if (!reference || !bdev_get_integrity(reference->bdev))
2084                 return 0;
2085         /*
2086          * All component devices are integrity capable and have matching
2087          * profiles, register the common profile for the md device.
2088          */
2089         if (blk_integrity_register(mddev->gendisk,
2090                         bdev_get_integrity(reference->bdev)) != 0) {
2091                 printk(KERN_ERR "md: failed to register integrity for %s\n",
2092                         mdname(mddev));
2093                 return -EINVAL;
2094         }
2095         printk(KERN_NOTICE "md: data integrity enabled on %s\n", mdname(mddev));
2096         if (bioset_integrity_create(mddev->bio_set, BIO_POOL_SIZE)) {
2097                 printk(KERN_ERR "md: failed to create integrity pool for %s\n",
2098                        mdname(mddev));
2099                 return -EINVAL;
2100         }
2101         return 0;
2102 }
2103 EXPORT_SYMBOL(md_integrity_register);
2104
2105 /* Disable data integrity if non-capable/non-matching disk is being added */
2106 void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev)
2107 {
2108         struct blk_integrity *bi_rdev = bdev_get_integrity(rdev->bdev);
2109         struct blk_integrity *bi_mddev = blk_get_integrity(mddev->gendisk);
2110
2111         if (!bi_mddev) /* nothing to do */
2112                 return;
2113         if (rdev->raid_disk < 0) /* skip spares */
2114                 return;
2115         if (bi_rdev && blk_integrity_compare(mddev->gendisk,
2116                                              rdev->bdev->bd_disk) >= 0)
2117                 return;
2118         printk(KERN_NOTICE "disabling data integrity on %s\n", mdname(mddev));
2119         blk_integrity_unregister(mddev->gendisk);
2120 }
2121 EXPORT_SYMBOL(md_integrity_add_rdev);
2122
2123 static int bind_rdev_to_array(struct md_rdev * rdev, struct mddev * mddev)
2124 {
2125         char b[BDEVNAME_SIZE];
2126         struct kobject *ko;
2127         char *s;
2128         int err;
2129
2130         if (rdev->mddev) {
2131                 MD_BUG();
2132                 return -EINVAL;
2133         }
2134
2135         /* prevent duplicates */
2136         if (find_rdev(mddev, rdev->bdev->bd_dev))
2137                 return -EEXIST;
2138
2139         /* make sure rdev->sectors exceeds mddev->dev_sectors */
2140         if (rdev->sectors && (mddev->dev_sectors == 0 ||
2141                         rdev->sectors < mddev->dev_sectors)) {
2142                 if (mddev->pers) {
2143                         /* Cannot change size, so fail
2144                          * If mddev->level <= 0, then we don't care
2145                          * about aligning sizes (e.g. linear)
2146                          */
2147                         if (mddev->level > 0)
2148                                 return -ENOSPC;
2149                 } else
2150                         mddev->dev_sectors = rdev->sectors;
2151         }
2152
2153         /* Verify rdev->desc_nr is unique.
2154          * If it is -1, assign a free number, else
2155          * check number is not in use
2156          */
2157         if (rdev->desc_nr < 0) {
2158                 int choice = 0;
2159                 if (mddev->pers) choice = mddev->raid_disks;
2160                 while (find_rdev_nr(mddev, choice))
2161                         choice++;
2162                 rdev->desc_nr = choice;
2163         } else {
2164                 if (find_rdev_nr(mddev, rdev->desc_nr))
2165                         return -EBUSY;
2166         }
2167         if (mddev->max_disks && rdev->desc_nr >= mddev->max_disks) {
2168                 printk(KERN_WARNING "md: %s: array is limited to %d devices\n",
2169                        mdname(mddev), mddev->max_disks);
2170                 return -EBUSY;
2171         }
2172         bdevname(rdev->bdev,b);
2173         while ( (s=strchr(b, '/')) != NULL)
2174                 *s = '!';
2175
2176         rdev->mddev = mddev;
2177         printk(KERN_INFO "md: bind<%s>\n", b);
2178
2179         if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
2180                 goto fail;
2181
2182         ko = &part_to_dev(rdev->bdev->bd_part)->kobj;
2183         if (sysfs_create_link(&rdev->kobj, ko, "block"))
2184                 /* failure here is OK */;
2185         rdev->sysfs_state = sysfs_get_dirent_safe(rdev->kobj.sd, "state");
2186
2187         list_add_rcu(&rdev->same_set, &mddev->disks);
2188         bd_link_disk_holder(rdev->bdev, mddev->gendisk);
2189
2190         /* May as well allow recovery to be retried once */
2191         mddev->recovery_disabled++;
2192
2193         return 0;
2194
2195  fail:
2196         printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
2197                b, mdname(mddev));
2198         return err;
2199 }
2200
2201 static void md_delayed_delete(struct work_struct *ws)
2202 {
2203         struct md_rdev *rdev = container_of(ws, struct md_rdev, del_work);
2204         kobject_del(&rdev->kobj);
2205         kobject_put(&rdev->kobj);
2206 }
2207
2208 static void unbind_rdev_from_array(struct md_rdev * rdev)
2209 {
2210         char b[BDEVNAME_SIZE];
2211         if (!rdev->mddev) {
2212                 MD_BUG();
2213                 return;
2214         }
2215         bd_unlink_disk_holder(rdev->bdev, rdev->mddev->gendisk);
2216         list_del_rcu(&rdev->same_set);
2217         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
2218         rdev->mddev = NULL;
2219         sysfs_remove_link(&rdev->kobj, "block");
2220         sysfs_put(rdev->sysfs_state);
2221         rdev->sysfs_state = NULL;
2222         rdev->badblocks.count = 0;
2223         /* We need to delay this, otherwise we can deadlock when
2224          * writing to 'remove' to "dev/state".  We also need
2225          * to delay it due to rcu usage.
2226          */
2227         synchronize_rcu();
2228         INIT_WORK(&rdev->del_work, md_delayed_delete);
2229         kobject_get(&rdev->kobj);
2230         queue_work(md_misc_wq, &rdev->del_work);
2231 }
2232
2233 /*
2234  * prevent the device from being mounted, repartitioned or
2235  * otherwise reused by a RAID array (or any other kernel
2236  * subsystem), by bd_claiming the device.
2237  */
2238 static int lock_rdev(struct md_rdev *rdev, dev_t dev, int shared)
2239 {
2240         int err = 0;
2241         struct block_device *bdev;
2242         char b[BDEVNAME_SIZE];
2243
2244         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
2245                                  shared ? (struct md_rdev *)lock_rdev : rdev);
2246         if (IS_ERR(bdev)) {
2247                 printk(KERN_ERR "md: could not open %s.\n",
2248                         __bdevname(dev, b));
2249                 return PTR_ERR(bdev);
2250         }
2251         rdev->bdev = bdev;
2252         return err;
2253 }
2254
2255 static void unlock_rdev(struct md_rdev *rdev)
2256 {
2257         struct block_device *bdev = rdev->bdev;
2258         rdev->bdev = NULL;
2259         if (!bdev)
2260                 MD_BUG();
2261         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
2262 }
2263
2264 void md_autodetect_dev(dev_t dev);
2265
2266 static void export_rdev(struct md_rdev * rdev)
2267 {
2268         char b[BDEVNAME_SIZE];
2269         printk(KERN_INFO "md: export_rdev(%s)\n",
2270                 bdevname(rdev->bdev,b));
2271         if (rdev->mddev)
2272                 MD_BUG();
2273         md_rdev_clear(rdev);
2274 #ifndef MODULE
2275         if (test_bit(AutoDetected, &rdev->flags))
2276                 md_autodetect_dev(rdev->bdev->bd_dev);
2277 #endif
2278         unlock_rdev(rdev);
2279         kobject_put(&rdev->kobj);
2280 }
2281
2282 static void kick_rdev_from_array(struct md_rdev * rdev)
2283 {
2284         unbind_rdev_from_array(rdev);
2285         export_rdev(rdev);
2286 }
2287
2288 static void export_array(struct mddev *mddev)
2289 {
2290         struct md_rdev *rdev, *tmp;
2291
2292         rdev_for_each_safe(rdev, tmp, mddev) {
2293                 if (!rdev->mddev) {
2294                         MD_BUG();
2295                         continue;
2296                 }
2297                 kick_rdev_from_array(rdev);
2298         }
2299         if (!list_empty(&mddev->disks))
2300                 MD_BUG();
2301         mddev->raid_disks = 0;
2302         mddev->major_version = 0;
2303 }
2304
2305 static void print_desc(mdp_disk_t *desc)
2306 {
2307         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
2308                 desc->major,desc->minor,desc->raid_disk,desc->state);
2309 }
2310
2311 static void print_sb_90(mdp_super_t *sb)
2312 {
2313         int i;
2314
2315         printk(KERN_INFO
2316                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
2317                 sb->major_version, sb->minor_version, sb->patch_version,
2318                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
2319                 sb->ctime);
2320         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
2321                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
2322                 sb->md_minor, sb->layout, sb->chunk_size);
2323         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
2324                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
2325                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
2326                 sb->failed_disks, sb->spare_disks,
2327                 sb->sb_csum, (unsigned long)sb->events_lo);
2328
2329         printk(KERN_INFO);
2330         for (i = 0; i < MD_SB_DISKS; i++) {
2331                 mdp_disk_t *desc;
2332
2333                 desc = sb->disks + i;
2334                 if (desc->number || desc->major || desc->minor ||
2335                     desc->raid_disk || (desc->state && (desc->state != 4))) {
2336                         printk("     D %2d: ", i);
2337                         print_desc(desc);
2338                 }
2339         }
2340         printk(KERN_INFO "md:     THIS: ");
2341         print_desc(&sb->this_disk);
2342 }
2343
2344 static void print_sb_1(struct mdp_superblock_1 *sb)
2345 {
2346         __u8 *uuid;
2347
2348         uuid = sb->set_uuid;
2349         printk(KERN_INFO
2350                "md:  SB: (V:%u) (F:0x%08x) Array-ID:<%pU>\n"
2351                "md:    Name: \"%s\" CT:%llu\n",
2352                 le32_to_cpu(sb->major_version),
2353                 le32_to_cpu(sb->feature_map),
2354                 uuid,
2355                 sb->set_name,
2356                 (unsigned long long)le64_to_cpu(sb->ctime)
2357                        & MD_SUPERBLOCK_1_TIME_SEC_MASK);
2358
2359         uuid = sb->device_uuid;
2360         printk(KERN_INFO
2361                "md:       L%u SZ%llu RD:%u LO:%u CS:%u DO:%llu DS:%llu SO:%llu"
2362                         " RO:%llu\n"
2363                "md:     Dev:%08x UUID: %pU\n"
2364                "md:       (F:0x%08x) UT:%llu Events:%llu ResyncOffset:%llu CSUM:0x%08x\n"
2365                "md:         (MaxDev:%u) \n",
2366                 le32_to_cpu(sb->level),
2367                 (unsigned long long)le64_to_cpu(sb->size),
2368                 le32_to_cpu(sb->raid_disks),
2369                 le32_to_cpu(sb->layout),
2370                 le32_to_cpu(sb->chunksize),
2371                 (unsigned long long)le64_to_cpu(sb->data_offset),
2372                 (unsigned long long)le64_to_cpu(sb->data_size),
2373                 (unsigned long long)le64_to_cpu(sb->super_offset),
2374                 (unsigned long long)le64_to_cpu(sb->recovery_offset),
2375                 le32_to_cpu(sb->dev_number),
2376                 uuid,
2377                 sb->devflags,
2378                 (unsigned long long)le64_to_cpu(sb->utime) & MD_SUPERBLOCK_1_TIME_SEC_MASK,
2379                 (unsigned long long)le64_to_cpu(sb->events),
2380                 (unsigned long long)le64_to_cpu(sb->resync_offset),
2381                 le32_to_cpu(sb->sb_csum),
2382                 le32_to_cpu(sb->max_dev)
2383                 );
2384 }
2385
2386 static void print_rdev(struct md_rdev *rdev, int major_version)
2387 {
2388         char b[BDEVNAME_SIZE];
2389         printk(KERN_INFO "md: rdev %s, Sect:%08llu F:%d S:%d DN:%u\n",
2390                 bdevname(rdev->bdev, b), (unsigned long long)rdev->sectors,
2391                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
2392                 rdev->desc_nr);
2393         if (rdev->sb_loaded) {
2394                 printk(KERN_INFO "md: rdev superblock (MJ:%d):\n", major_version);
2395                 switch (major_version) {
2396                 case 0:
2397                         print_sb_90(page_address(rdev->sb_page));
2398                         break;
2399                 case 1:
2400                         print_sb_1(page_address(rdev->sb_page));
2401                         break;
2402                 }
2403         } else
2404                 printk(KERN_INFO "md: no rdev superblock!\n");
2405 }
2406
2407 static void md_print_devices(void)
2408 {
2409         struct list_head *tmp;
2410         struct md_rdev *rdev;
2411         struct mddev *mddev;
2412         char b[BDEVNAME_SIZE];
2413
2414         printk("\n");
2415         printk("md:     **********************************\n");
2416         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
2417         printk("md:     **********************************\n");
2418         for_each_mddev(mddev, tmp) {
2419
2420                 if (mddev->bitmap)
2421                         bitmap_print_sb(mddev->bitmap);
2422                 else
2423                         printk("%s: ", mdname(mddev));
2424                 rdev_for_each(rdev, mddev)
2425                         printk("<%s>", bdevname(rdev->bdev,b));
2426                 printk("\n");
2427
2428                 rdev_for_each(rdev, mddev)
2429                         print_rdev(rdev, mddev->major_version);
2430         }
2431         printk("md:     **********************************\n");
2432         printk("\n");
2433 }
2434
2435
2436 static void sync_sbs(struct mddev * mddev, int nospares)
2437 {
2438         /* Update each superblock (in-memory image), but
2439          * if we are allowed to, skip spares which already
2440          * have the right event counter, or have one earlier
2441          * (which would mean they aren't being marked as dirty
2442          * with the rest of the array)
2443          */
2444         struct md_rdev *rdev;
2445         rdev_for_each(rdev, mddev) {
2446                 if (rdev->sb_events == mddev->events ||
2447                     (nospares &&
2448                      rdev->raid_disk < 0 &&
2449                      rdev->sb_events+1 == mddev->events)) {
2450                         /* Don't update this superblock */
2451                         rdev->sb_loaded = 2;
2452                 } else {
2453                         sync_super(mddev, rdev);
2454                         rdev->sb_loaded = 1;
2455                 }
2456         }
2457 }
2458
2459 static void md_update_sb(struct mddev * mddev, int force_change)
2460 {
2461         struct md_rdev *rdev;
2462         int sync_req;
2463         int nospares = 0;
2464         int any_badblocks_changed = 0;
2465
2466 repeat:
2467         /* First make sure individual recovery_offsets are correct */
2468         rdev_for_each(rdev, mddev) {
2469                 if (rdev->raid_disk >= 0 &&
2470                     mddev->delta_disks >= 0 &&
2471                     !test_bit(In_sync, &rdev->flags) &&
2472                     mddev->curr_resync_completed > rdev->recovery_offset)
2473                                 rdev->recovery_offset = mddev->curr_resync_completed;
2474
2475         }
2476         if (!mddev->persistent) {
2477                 clear_bit(MD_CHANGE_CLEAN, &mddev->flags);
2478                 clear_bit(MD_CHANGE_DEVS, &mddev->flags);
2479                 if (!mddev->external) {
2480                         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2481                         rdev_for_each(rdev, mddev) {
2482                                 if (rdev->badblocks.changed) {
2483                                         rdev->badblocks.changed = 0;
2484                                         md_ack_all_badblocks(&rdev->badblocks);
2485                                         md_error(mddev, rdev);
2486                                 }
2487                                 clear_bit(Blocked, &rdev->flags);
2488                                 clear_bit(BlockedBadBlocks, &rdev->flags);
2489                                 wake_up(&rdev->blocked_wait);
2490                         }
2491                 }
2492                 wake_up(&mddev->sb_wait);
2493                 return;
2494         }
2495
2496         spin_lock_irq(&mddev->write_lock);
2497
2498         mddev->utime = get_seconds();
2499
2500         if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
2501                 force_change = 1;
2502         if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
2503                 /* just a clean<-> dirty transition, possibly leave spares alone,
2504                  * though if events isn't the right even/odd, we will have to do
2505                  * spares after all
2506                  */
2507                 nospares = 1;
2508         if (force_change)
2509                 nospares = 0;
2510         if (mddev->degraded)
2511                 /* If the array is degraded, then skipping spares is both
2512                  * dangerous and fairly pointless.
2513                  * Dangerous because a device that was removed from the array
2514                  * might have a event_count that still looks up-to-date,
2515                  * so it can be re-added without a resync.
2516                  * Pointless because if there are any spares to skip,
2517                  * then a recovery will happen and soon that array won't
2518                  * be degraded any more and the spare can go back to sleep then.
2519                  */
2520                 nospares = 0;
2521
2522         sync_req = mddev->in_sync;
2523
2524         /* If this is just a dirty<->clean transition, and the array is clean
2525          * and 'events' is odd, we can roll back to the previous clean state */
2526         if (nospares
2527             && (mddev->in_sync && mddev->recovery_cp == MaxSector)
2528             && mddev->can_decrease_events
2529             && mddev->events != 1) {
2530                 mddev->events--;
2531                 mddev->can_decrease_events = 0;
2532         } else {
2533                 /* otherwise we have to go forward and ... */
2534                 mddev->events ++;
2535                 mddev->can_decrease_events = nospares;
2536         }
2537
2538         if (!mddev->events) {
2539                 /*
2540                  * oops, this 64-bit counter should never wrap.
2541                  * Either we are in around ~1 trillion A.C., assuming
2542                  * 1 reboot per second, or we have a bug:
2543                  */
2544                 MD_BUG();
2545                 mddev->events --;
2546         }
2547
2548         rdev_for_each(rdev, mddev) {
2549                 if (rdev->badblocks.changed)
2550                         any_badblocks_changed++;
2551                 if (test_bit(Faulty, &rdev->flags))
2552                         set_bit(FaultRecorded, &rdev->flags);
2553         }
2554
2555         sync_sbs(mddev, nospares);
2556         spin_unlock_irq(&mddev->write_lock);
2557
2558         pr_debug("md: updating %s RAID superblock on device (in sync %d)\n",
2559                  mdname(mddev), mddev->in_sync);
2560
2561         bitmap_update_sb(mddev->bitmap);
2562         rdev_for_each(rdev, mddev) {
2563                 char b[BDEVNAME_SIZE];
2564
2565                 if (rdev->sb_loaded != 1)
2566                         continue; /* no noise on spare devices */
2567
2568                 if (!test_bit(Faulty, &rdev->flags) &&
2569                     rdev->saved_raid_disk == -1) {
2570                         md_super_write(mddev,rdev,
2571                                        rdev->sb_start, rdev->sb_size,
2572                                        rdev->sb_page);
2573                         pr_debug("md: (write) %s's sb offset: %llu\n",
2574                                  bdevname(rdev->bdev, b),
2575                                  (unsigned long long)rdev->sb_start);
2576                         rdev->sb_events = mddev->events;
2577                         if (rdev->badblocks.size) {
2578                                 md_super_write(mddev, rdev,
2579                                                rdev->badblocks.sector,
2580                                                rdev->badblocks.size << 9,
2581                                                rdev->bb_page);
2582                                 rdev->badblocks.size = 0;
2583                         }
2584
2585                 } else if (test_bit(Faulty, &rdev->flags))
2586                         pr_debug("md: %s (skipping faulty)\n",
2587                                  bdevname(rdev->bdev, b));
2588                 else
2589                         pr_debug("(skipping incremental s/r ");
2590
2591                 if (mddev->level == LEVEL_MULTIPATH)
2592                         /* only need to write one superblock... */
2593                         break;
2594         }
2595         md_super_wait(mddev);
2596         /* if there was a failure, MD_CHANGE_DEVS was set, and we re-write super */
2597
2598         spin_lock_irq(&mddev->write_lock);
2599         if (mddev->in_sync != sync_req ||
2600             test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
2601                 /* have to write it out again */
2602                 spin_unlock_irq(&mddev->write_lock);
2603                 goto repeat;
2604         }
2605         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2606         spin_unlock_irq(&mddev->write_lock);
2607         wake_up(&mddev->sb_wait);
2608         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2609                 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
2610
2611         rdev_for_each(rdev, mddev) {
2612                 if (test_and_clear_bit(FaultRecorded, &rdev->flags))
2613                         clear_bit(Blocked, &rdev->flags);
2614
2615                 if (any_badblocks_changed)
2616                         md_ack_all_badblocks(&rdev->badblocks);
2617                 clear_bit(BlockedBadBlocks, &rdev->flags);
2618                 wake_up(&rdev->blocked_wait);
2619         }
2620 }
2621
2622 /* words written to sysfs files may, or may not, be \n terminated.
2623  * We want to accept with case. For this we use cmd_match.
2624  */
2625 static int cmd_match(const char *cmd, const char *str)
2626 {
2627         /* See if cmd, written into a sysfs file, matches
2628          * str.  They must either be the same, or cmd can
2629          * have a trailing newline
2630          */
2631         while (*cmd && *str && *cmd == *str) {
2632                 cmd++;
2633                 str++;
2634         }
2635         if (*cmd == '\n')
2636                 cmd++;
2637         if (*str || *cmd)
2638                 return 0;
2639         return 1;
2640 }
2641
2642 struct rdev_sysfs_entry {
2643         struct attribute attr;
2644         ssize_t (*show)(struct md_rdev *, char *);
2645         ssize_t (*store)(struct md_rdev *, const char *, size_t);
2646 };
2647
2648 static ssize_t
2649 state_show(struct md_rdev *rdev, char *page)
2650 {
2651         char *sep = "";
2652         size_t len = 0;
2653
2654         if (test_bit(Faulty, &rdev->flags) ||
2655             rdev->badblocks.unacked_exist) {
2656                 len+= sprintf(page+len, "%sfaulty",sep);
2657                 sep = ",";
2658         }
2659         if (test_bit(In_sync, &rdev->flags)) {
2660                 len += sprintf(page+len, "%sin_sync",sep);
2661                 sep = ",";
2662         }
2663         if (test_bit(WriteMostly, &rdev->flags)) {
2664                 len += sprintf(page+len, "%swrite_mostly",sep);
2665                 sep = ",";
2666         }
2667         if (test_bit(Blocked, &rdev->flags) ||
2668             (rdev->badblocks.unacked_exist
2669              && !test_bit(Faulty, &rdev->flags))) {
2670                 len += sprintf(page+len, "%sblocked", sep);
2671                 sep = ",";
2672         }
2673         if (!test_bit(Faulty, &rdev->flags) &&
2674             !test_bit(In_sync, &rdev->flags)) {
2675                 len += sprintf(page+len, "%sspare", sep);
2676                 sep = ",";
2677         }
2678         if (test_bit(WriteErrorSeen, &rdev->flags)) {
2679                 len += sprintf(page+len, "%swrite_error", sep);
2680                 sep = ",";
2681         }
2682         if (test_bit(WantReplacement, &rdev->flags)) {
2683                 len += sprintf(page+len, "%swant_replacement", sep);
2684                 sep = ",";
2685         }
2686         if (test_bit(Replacement, &rdev->flags)) {
2687                 len += sprintf(page+len, "%sreplacement", sep);
2688                 sep = ",";
2689         }
2690
2691         return len+sprintf(page+len, "\n");
2692 }
2693
2694 static ssize_t
2695 state_store(struct md_rdev *rdev, const char *buf, size_t len)
2696 {
2697         /* can write
2698          *  faulty  - simulates an error
2699          *  remove  - disconnects the device
2700          *  writemostly - sets write_mostly
2701          *  -writemostly - clears write_mostly
2702          *  blocked - sets the Blocked flags
2703          *  -blocked - clears the Blocked and possibly simulates an error
2704          *  insync - sets Insync providing device isn't active
2705          *  write_error - sets WriteErrorSeen
2706          *  -write_error - clears WriteErrorSeen
2707          */
2708         int err = -EINVAL;
2709         if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
2710                 md_error(rdev->mddev, rdev);
2711                 if (test_bit(Faulty, &rdev->flags))
2712                         err = 0;
2713                 else
2714                         err = -EBUSY;
2715         } else if (cmd_match(buf, "remove")) {
2716                 if (rdev->raid_disk >= 0)
2717                         err = -EBUSY;
2718                 else {
2719                         struct mddev *mddev = rdev->mddev;
2720                         kick_rdev_from_array(rdev);
2721                         if (mddev->pers)
2722                                 md_update_sb(mddev, 1);
2723                         md_new_event(mddev);
2724                         err = 0;
2725                 }
2726         } else if (cmd_match(buf, "writemostly")) {
2727                 set_bit(WriteMostly, &rdev->flags);
2728                 err = 0;
2729         } else if (cmd_match(buf, "-writemostly")) {
2730                 clear_bit(WriteMostly, &rdev->flags);
2731                 err = 0;
2732         } else if (cmd_match(buf, "blocked")) {
2733                 set_bit(Blocked, &rdev->flags);
2734                 err = 0;
2735         } else if (cmd_match(buf, "-blocked")) {
2736                 if (!test_bit(Faulty, &rdev->flags) &&
2737                     rdev->badblocks.unacked_exist) {
2738                         /* metadata handler doesn't understand badblocks,
2739                          * so we need to fail the device
2740                          */
2741                         md_error(rdev->mddev, rdev);
2742                 }
2743                 clear_bit(Blocked, &rdev->flags);
2744                 clear_bit(BlockedBadBlocks, &rdev->flags);
2745                 wake_up(&rdev->blocked_wait);
2746                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2747                 md_wakeup_thread(rdev->mddev->thread);
2748
2749                 err = 0;
2750         } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
2751                 set_bit(In_sync, &rdev->flags);
2752                 err = 0;
2753         } else if (cmd_match(buf, "write_error")) {
2754                 set_bit(WriteErrorSeen, &rdev->flags);
2755                 err = 0;
2756         } else if (cmd_match(buf, "-write_error")) {
2757                 clear_bit(WriteErrorSeen, &rdev->flags);
2758                 err = 0;
2759         } else if (cmd_match(buf, "want_replacement")) {
2760                 /* Any non-spare device that is not a replacement can
2761                  * become want_replacement at any time, but we then need to
2762                  * check if recovery is needed.
2763                  */
2764                 if (rdev->raid_disk >= 0 &&
2765                     !test_bit(Replacement, &rdev->flags))
2766                         set_bit(WantReplacement, &rdev->flags);
2767                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2768                 md_wakeup_thread(rdev->mddev->thread);
2769                 err = 0;
2770         } else if (cmd_match(buf, "-want_replacement")) {
2771                 /* Clearing 'want_replacement' is always allowed.
2772                  * Once replacements starts it is too late though.
2773                  */
2774                 err = 0;
2775                 clear_bit(WantReplacement, &rdev->flags);
2776         } else if (cmd_match(buf, "replacement")) {
2777                 /* Can only set a device as a replacement when array has not
2778                  * yet been started.  Once running, replacement is automatic
2779                  * from spares, or by assigning 'slot'.
2780                  */
2781                 if (rdev->mddev->pers)
2782                         err = -EBUSY;
2783                 else {
2784                         set_bit(Replacement, &rdev->flags);
2785                         err = 0;
2786                 }
2787         } else if (cmd_match(buf, "-replacement")) {
2788                 /* Similarly, can only clear Replacement before start */
2789                 if (rdev->mddev->pers)
2790                         err = -EBUSY;
2791                 else {
2792                         clear_bit(Replacement, &rdev->flags);
2793                         err = 0;
2794                 }
2795         }
2796         if (!err)
2797                 sysfs_notify_dirent_safe(rdev->sysfs_state);
2798         return err ? err : len;
2799 }
2800 static struct rdev_sysfs_entry rdev_state =
2801 __ATTR(state, S_IRUGO|S_IWUSR, state_show, state_store);
2802
2803 static ssize_t
2804 errors_show(struct md_rdev *rdev, char *page)
2805 {
2806         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
2807 }
2808
2809 static ssize_t
2810 errors_store(struct md_rdev *rdev, const char *buf, size_t len)
2811 {
2812         char *e;
2813         unsigned long n = simple_strtoul(buf, &e, 10);
2814         if (*buf && (*e == 0 || *e == '\n')) {
2815                 atomic_set(&rdev->corrected_errors, n);
2816                 return len;
2817         }
2818         return -EINVAL;
2819 }
2820 static struct rdev_sysfs_entry rdev_errors =
2821 __ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
2822
2823 static ssize_t
2824 slot_show(struct md_rdev *rdev, char *page)
2825 {
2826         if (rdev->raid_disk < 0)
2827                 return sprintf(page, "none\n");
2828         else
2829                 return sprintf(page, "%d\n", rdev->raid_disk);
2830 }
2831
2832 static ssize_t
2833 slot_store(struct md_rdev *rdev, const char *buf, size_t len)
2834 {
2835         char *e;
2836         int err;
2837         int slot = simple_strtoul(buf, &e, 10);
2838         if (strncmp(buf, "none", 4)==0)
2839                 slot = -1;
2840         else if (e==buf || (*e && *e!= '\n'))
2841                 return -EINVAL;
2842         if (rdev->mddev->pers && slot == -1) {
2843                 /* Setting 'slot' on an active array requires also
2844                  * updating the 'rd%d' link, and communicating
2845                  * with the personality with ->hot_*_disk.
2846                  * For now we only support removing
2847                  * failed/spare devices.  This normally happens automatically,
2848                  * but not when the metadata is externally managed.
2849                  */
2850                 if (rdev->raid_disk == -1)
2851                         return -EEXIST;
2852                 /* personality does all needed checks */
2853                 if (rdev->mddev->pers->hot_remove_disk == NULL)
2854                         return -EINVAL;
2855                 err = rdev->mddev->pers->
2856                         hot_remove_disk(rdev->mddev, rdev);
2857                 if (err)
2858                         return err;
2859                 sysfs_unlink_rdev(rdev->mddev, rdev);
2860                 rdev->raid_disk = -1;
2861                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2862                 md_wakeup_thread(rdev->mddev->thread);
2863         } else if (rdev->mddev->pers) {
2864                 /* Activating a spare .. or possibly reactivating
2865                  * if we ever get bitmaps working here.
2866                  */
2867
2868                 if (rdev->raid_disk != -1)
2869                         return -EBUSY;
2870
2871                 if (test_bit(MD_RECOVERY_RUNNING, &rdev->mddev->recovery))
2872                         return -EBUSY;
2873
2874                 if (rdev->mddev->pers->hot_add_disk == NULL)
2875                         return -EINVAL;
2876
2877                 if (slot >= rdev->mddev->raid_disks &&
2878                     slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
2879                         return -ENOSPC;
2880
2881                 rdev->raid_disk = slot;
2882                 if (test_bit(In_sync, &rdev->flags))
2883                         rdev->saved_raid_disk = slot;
2884                 else
2885                         rdev->saved_raid_disk = -1;
2886                 clear_bit(In_sync, &rdev->flags);
2887                 err = rdev->mddev->pers->
2888                         hot_add_disk(rdev->mddev, rdev);
2889                 if (err) {
2890                         rdev->raid_disk = -1;
2891                         return err;
2892                 } else
2893                         sysfs_notify_dirent_safe(rdev->sysfs_state);
2894                 if (sysfs_link_rdev(rdev->mddev, rdev))
2895                         /* failure here is OK */;
2896                 /* don't wakeup anyone, leave that to userspace. */
2897         } else {
2898                 if (slot >= rdev->mddev->raid_disks &&
2899                     slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
2900                         return -ENOSPC;
2901                 rdev->raid_disk = slot;
2902                 /* assume it is working */
2903                 clear_bit(Faulty, &rdev->flags);
2904                 clear_bit(WriteMostly, &rdev->flags);
2905                 set_bit(In_sync, &rdev->flags);
2906                 sysfs_notify_dirent_safe(rdev->sysfs_state);
2907         }
2908         return len;
2909 }
2910
2911
2912 static struct rdev_sysfs_entry rdev_slot =
2913 __ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
2914
2915 static ssize_t
2916 offset_show(struct md_rdev *rdev, char *page)
2917 {
2918         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
2919 }
2920
2921 static ssize_t
2922 offset_store(struct md_rdev *rdev, const char *buf, size_t len)
2923 {
2924         unsigned long long offset;
2925         if (strict_strtoull(buf, 10, &offset) < 0)
2926                 return -EINVAL;
2927         if (rdev->mddev->pers && rdev->raid_disk >= 0)
2928                 return -EBUSY;
2929         if (rdev->sectors && rdev->mddev->external)
2930                 /* Must set offset before size, so overlap checks
2931                  * can be sane */
2932                 return -EBUSY;
2933         rdev->data_offset = offset;
2934         rdev->new_data_offset = offset;
2935         return len;
2936 }
2937
2938 static struct rdev_sysfs_entry rdev_offset =
2939 __ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
2940
2941 static ssize_t new_offset_show(struct md_rdev *rdev, char *page)
2942 {
2943         return sprintf(page, "%llu\n",
2944                        (unsigned long long)rdev->new_data_offset);
2945 }
2946
2947 static ssize_t new_offset_store(struct md_rdev *rdev,
2948                                 const char *buf, size_t len)
2949 {
2950         unsigned long long new_offset;
2951         struct mddev *mddev = rdev->mddev;
2952
2953         if (strict_strtoull(buf, 10, &new_offset) < 0)
2954                 return -EINVAL;
2955
2956         if (mddev->sync_thread)
2957                 return -EBUSY;
2958         if (new_offset == rdev->data_offset)
2959                 /* reset is always permitted */
2960                 ;
2961         else if (new_offset > rdev->data_offset) {
2962                 /* must not push array size beyond rdev_sectors */
2963                 if (new_offset - rdev->data_offset
2964                     + mddev->dev_sectors > rdev->sectors)
2965                                 return -E2BIG;
2966         }
2967         /* Metadata worries about other space details. */
2968
2969         /* decreasing the offset is inconsistent with a backwards
2970          * reshape.
2971          */
2972         if (new_offset < rdev->data_offset &&
2973             mddev->reshape_backwards)
2974                 return -EINVAL;
2975         /* Increasing offset is inconsistent with forwards
2976          * reshape.  reshape_direction should be set to
2977          * 'backwards' first.
2978          */
2979         if (new_offset > rdev->data_offset &&
2980             !mddev->reshape_backwards)
2981                 return -EINVAL;
2982
2983         if (mddev->pers && mddev->persistent &&
2984             !super_types[mddev->major_version]
2985             .allow_new_offset(rdev, new_offset))
2986                 return -E2BIG;
2987         rdev->new_data_offset = new_offset;
2988         if (new_offset > rdev->data_offset)
2989                 mddev->reshape_backwards = 1;
2990         else if (new_offset < rdev->data_offset)
2991                 mddev->reshape_backwards = 0;
2992
2993         return len;
2994 }
2995 static struct rdev_sysfs_entry rdev_new_offset =
2996 __ATTR(new_offset, S_IRUGO|S_IWUSR, new_offset_show, new_offset_store);
2997
2998 static ssize_t
2999 rdev_size_show(struct md_rdev *rdev, char *page)
3000 {
3001         return sprintf(page, "%llu\n", (unsigned long long)rdev->sectors / 2);
3002 }
3003
3004 static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
3005 {
3006         /* check if two start/length pairs overlap */
3007         if (s1+l1 <= s2)
3008                 return 0;
3009         if (s2+l2 <= s1)
3010                 return 0;
3011         return 1;
3012 }
3013
3014 static int strict_blocks_to_sectors(const char *buf, sector_t *sectors)
3015 {
3016         unsigned long long blocks;
3017         sector_t new;
3018
3019         if (strict_strtoull(buf, 10, &blocks) < 0)
3020                 return -EINVAL;
3021
3022         if (blocks & 1ULL << (8 * sizeof(blocks) - 1))
3023                 return -EINVAL; /* sector conversion overflow */
3024
3025         new = blocks * 2;
3026         if (new != blocks * 2)
3027                 return -EINVAL; /* unsigned long long to sector_t overflow */
3028
3029         *sectors = new;
3030         return 0;
3031 }
3032
3033 static ssize_t
3034 rdev_size_store(struct md_rdev *rdev, const char *buf, size_t len)
3035 {
3036         struct mddev *my_mddev = rdev->mddev;
3037         sector_t oldsectors = rdev->sectors;
3038         sector_t sectors;
3039
3040         if (strict_blocks_to_sectors(buf, &sectors) < 0)
3041                 return -EINVAL;
3042         if (rdev->data_offset != rdev->new_data_offset)
3043                 return -EINVAL; /* too confusing */
3044         if (my_mddev->pers && rdev->raid_disk >= 0) {
3045                 if (my_mddev->persistent) {
3046                         sectors = super_types[my_mddev->major_version].
3047                                 rdev_size_change(rdev, sectors);
3048                         if (!sectors)
3049                                 return -EBUSY;
3050                 } else if (!sectors)
3051                         sectors = (i_size_read(rdev->bdev->bd_inode) >> 9) -
3052                                 rdev->data_offset;
3053         }
3054         if (sectors < my_mddev->dev_sectors)
3055                 return -EINVAL; /* component must fit device */
3056
3057         rdev->sectors = sectors;
3058         if (sectors > oldsectors && my_mddev->external) {
3059                 /* need to check that all other rdevs with the same ->bdev
3060                  * do not overlap.  We need to unlock the mddev to avoid
3061                  * a deadlock.  We have already changed rdev->sectors, and if
3062                  * we have to change it back, we will have the lock again.
3063                  */
3064                 struct mddev *mddev;
3065                 int overlap = 0;
3066                 struct list_head *tmp;
3067
3068                 mddev_unlock(my_mddev);
3069                 for_each_mddev(mddev, tmp) {
3070                         struct md_rdev *rdev2;
3071
3072                         mddev_lock(mddev);
3073                         rdev_for_each(rdev2, mddev)
3074                                 if (rdev->bdev == rdev2->bdev &&
3075                                     rdev != rdev2 &&
3076                                     overlaps(rdev->data_offset, rdev->sectors,
3077                                              rdev2->data_offset,
3078                                              rdev2->sectors)) {
3079                                         overlap = 1;
3080                                         break;
3081                                 }
3082                         mddev_unlock(mddev);
3083                         if (overlap) {
3084                                 mddev_put(mddev);
3085                                 break;
3086                         }
3087                 }
3088                 mddev_lock(my_mddev);
3089                 if (overlap) {
3090                         /* Someone else could have slipped in a size
3091                          * change here, but doing so is just silly.
3092                          * We put oldsectors back because we *know* it is
3093                          * safe, and trust userspace not to race with
3094                          * itself
3095                          */
3096                         rdev->sectors = oldsectors;
3097                         return -EBUSY;
3098                 }
3099         }
3100         return len;
3101 }
3102
3103 static struct rdev_sysfs_entry rdev_size =
3104 __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
3105
3106
3107 static ssize_t recovery_start_show(struct md_rdev *rdev, char *page)
3108 {
3109         unsigned long long recovery_start = rdev->recovery_offset;
3110
3111         if (test_bit(In_sync, &rdev->flags) ||
3112             recovery_start == MaxSector)
3113                 return sprintf(page, "none\n");
3114
3115         return sprintf(page, "%llu\n", recovery_start);
3116 }
3117
3118 static ssize_t recovery_start_store(struct md_rdev *rdev, const char *buf, size_t len)
3119 {
3120         unsigned long long recovery_start;
3121
3122         if (cmd_match(buf, "none"))
3123                 recovery_start = MaxSector;
3124         else if (strict_strtoull(buf, 10, &recovery_start))
3125                 return -EINVAL;
3126
3127         if (rdev->mddev->pers &&
3128             rdev->raid_disk >= 0)
3129                 return -EBUSY;
3130
3131         rdev->recovery_offset = recovery_start;
3132         if (recovery_start == MaxSector)
3133                 set_bit(In_sync, &rdev->flags);
3134         else
3135                 clear_bit(In_sync, &rdev->flags);
3136         return len;
3137 }
3138
3139 static struct rdev_sysfs_entry rdev_recovery_start =
3140 __ATTR(recovery_start, S_IRUGO|S_IWUSR, recovery_start_show, recovery_start_store);
3141
3142
3143 static ssize_t
3144 badblocks_show(struct badblocks *bb, char *page, int unack);
3145 static ssize_t
3146 badblocks_store(struct badblocks *bb, const char *page, size_t len, int unack);
3147
3148 static ssize_t bb_show(struct md_rdev *rdev, char *page)
3149 {
3150         return badblocks_show(&rdev->badblocks, page, 0);
3151 }
3152 static ssize_t bb_store(struct md_rdev *rdev, const char *page, size_t len)
3153 {
3154         int rv = badblocks_store(&rdev->badblocks, page, len, 0);
3155         /* Maybe that ack was all we needed */
3156         if (test_and_clear_bit(BlockedBadBlocks, &rdev->flags))
3157                 wake_up(&rdev->blocked_wait);
3158         return rv;
3159 }
3160 static struct rdev_sysfs_entry rdev_bad_blocks =
3161 __ATTR(bad_blocks, S_IRUGO|S_IWUSR, bb_show, bb_store);
3162
3163
3164 static ssize_t ubb_show(struct md_rdev *rdev, char *page)
3165 {
3166         return badblocks_show(&rdev->badblocks, page, 1);
3167 }
3168 static ssize_t ubb_store(struct md_rdev *rdev, const char *page, size_t len)
3169 {
3170         return badblocks_store(&rdev->badblocks, page, len, 1);
3171 }
3172 static struct rdev_sysfs_entry rdev_unack_bad_blocks =
3173 __ATTR(unacknowledged_bad_blocks, S_IRUGO|S_IWUSR, ubb_show, ubb_store);
3174
3175 static struct attribute *rdev_default_attrs[] = {
3176         &rdev_state.attr,
3177         &rdev_errors.attr,
3178         &rdev_slot.attr,
3179         &rdev_offset.attr,
3180         &rdev_new_offset.attr,
3181         &rdev_size.attr,
3182         &rdev_recovery_start.attr,
3183         &rdev_bad_blocks.attr,
3184         &rdev_unack_bad_blocks.attr,
3185         NULL,
3186 };
3187 static ssize_t
3188 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3189 {
3190         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3191         struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3192         struct mddev *mddev = rdev->mddev;
3193         ssize_t rv;
3194
3195         if (!entry->show)
3196                 return -EIO;
3197
3198         rv = mddev ? mddev_lock(mddev) : -EBUSY;
3199         if (!rv) {
3200                 if (rdev->mddev == NULL)
3201                         rv = -EBUSY;
3202                 else
3203                         rv = entry->show(rdev, page);
3204                 mddev_unlock(mddev);
3205         }
3206         return rv;
3207 }
3208
3209 static ssize_t
3210 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
3211               const char *page, size_t length)
3212 {
3213         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3214         struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3215         ssize_t rv;
3216         struct mddev *mddev = rdev->mddev;
3217
3218         if (!entry->store)
3219                 return -EIO;
3220         if (!capable(CAP_SYS_ADMIN))
3221                 return -EACCES;
3222         rv = mddev ? mddev_lock(mddev): -EBUSY;
3223         if (!rv) {
3224                 if (rdev->mddev == NULL)
3225                         rv = -EBUSY;
3226                 else
3227                         rv = entry->store(rdev, page, length);
3228                 mddev_unlock(mddev);
3229         }
3230         return rv;
3231 }
3232
3233 static void rdev_free(struct kobject *ko)
3234 {
3235         struct md_rdev *rdev = container_of(ko, struct md_rdev, kobj);
3236         kfree(rdev);
3237 }
3238 static const struct sysfs_ops rdev_sysfs_ops = {
3239         .show           = rdev_attr_show,
3240         .store          = rdev_attr_store,
3241 };
3242 static struct kobj_type rdev_ktype = {
3243         .release        = rdev_free,
3244         .sysfs_ops      = &rdev_sysfs_ops,
3245         .default_attrs  = rdev_default_attrs,
3246 };
3247
3248 int md_rdev_init(struct md_rdev *rdev)
3249 {
3250         rdev->desc_nr = -1;
3251         rdev->saved_raid_disk = -1;
3252         rdev->raid_disk = -1;
3253         rdev->flags = 0;
3254         rdev->data_offset = 0;
3255         rdev->new_data_offset = 0;
3256         rdev->sb_events = 0;
3257         rdev->last_read_error.tv_sec  = 0;
3258         rdev->last_read_error.tv_nsec = 0;
3259         rdev->sb_loaded = 0;
3260         rdev->bb_page = NULL;
3261         atomic_set(&rdev->nr_pending, 0);
3262         atomic_set(&rdev->read_errors, 0);
3263         atomic_set(&rdev->corrected_errors, 0);
3264
3265         INIT_LIST_HEAD(&rdev->same_set);
3266         init_waitqueue_head(&rdev->blocked_wait);
3267
3268         /* Add space to store bad block list.
3269          * This reserves the space even on arrays where it cannot
3270          * be used - I wonder if that matters
3271          */
3272         rdev->badblocks.count = 0;
3273         rdev->badblocks.shift = 0;
3274         rdev->badblocks.page = kmalloc(PAGE_SIZE, GFP_KERNEL);
3275         seqlock_init(&rdev->badblocks.lock);
3276         if (rdev->badblocks.page == NULL)
3277                 return -ENOMEM;
3278
3279         return 0;
3280 }
3281 EXPORT_SYMBOL_GPL(md_rdev_init);
3282 /*
3283  * Import a device. If 'super_format' >= 0, then sanity check the superblock
3284  *
3285  * mark the device faulty if:
3286  *
3287  *   - the device is nonexistent (zero size)
3288  *   - the device has no valid superblock
3289  *
3290  * a faulty rdev _never_ has rdev->sb set.
3291  */
3292 static struct md_rdev *md_import_device(dev_t newdev, int super_format, int super_minor)
3293 {
3294         char b[BDEVNAME_SIZE];
3295         int err;
3296         struct md_rdev *rdev;
3297         sector_t size;
3298
3299         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
3300         if (!rdev) {
3301                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
3302                 return ERR_PTR(-ENOMEM);
3303         }
3304
3305         err = md_rdev_init(rdev);
3306         if (err)
3307                 goto abort_free;
3308         err = alloc_disk_sb(rdev);
3309         if (err)
3310                 goto abort_free;
3311
3312         err = lock_rdev(rdev, newdev, super_format == -2);
3313         if (err)
3314                 goto abort_free;
3315
3316         kobject_init(&rdev->kobj, &rdev_ktype);
3317
3318         size = i_size_read(rdev->bdev->bd_inode) >> BLOCK_SIZE_BITS;
3319         if (!size) {
3320                 printk(KERN_WARNING
3321                         "md: %s has zero or unknown size, marking faulty!\n",
3322                         bdevname(rdev->bdev,b));
3323                 err = -EINVAL;
3324                 goto abort_free;
3325         }
3326
3327         if (super_format >= 0) {
3328                 err = super_types[super_format].
3329                         load_super(rdev, NULL, super_minor);
3330                 if (err == -EINVAL) {
3331                         printk(KERN_WARNING
3332                                 "md: %s does not have a valid v%d.%d "
3333                                "superblock, not importing!\n",
3334                                 bdevname(rdev->bdev,b),
3335                                super_format, super_minor);
3336                         goto abort_free;
3337                 }
3338                 if (err < 0) {
3339                         printk(KERN_WARNING
3340                                 "md: could not read %s's sb, not importing!\n",
3341                                 bdevname(rdev->bdev,b));
3342                         goto abort_free;
3343                 }
3344         }
3345         if (super_format == -1)
3346                 /* hot-add for 0.90, or non-persistent: so no badblocks */
3347                 rdev->badblocks.shift = -1;
3348
3349         return rdev;
3350
3351 abort_free:
3352         if (rdev->bdev)
3353                 unlock_rdev(rdev);
3354         md_rdev_clear(rdev);
3355         kfree(rdev);
3356         return ERR_PTR(err);
3357 }
3358
3359 /*
3360  * Check a full RAID array for plausibility
3361  */
3362
3363
3364 static void analyze_sbs(struct mddev * mddev)
3365 {
3366         int i;
3367         struct md_rdev *rdev, *freshest, *tmp;
3368         char b[BDEVNAME_SIZE];
3369
3370         freshest = NULL;
3371         rdev_for_each_safe(rdev, tmp, mddev)
3372                 switch (super_types[mddev->major_version].
3373                         load_super(rdev, freshest, mddev->minor_version)) {
3374                 case 1:
3375                         freshest = rdev;
3376                         break;
3377                 case 0:
3378                         break;
3379                 default:
3380                         printk( KERN_ERR \
3381                                 "md: fatal superblock inconsistency in %s"
3382                                 " -- removing from array\n",
3383                                 bdevname(rdev->bdev,b));
3384                         kick_rdev_from_array(rdev);
3385                 }
3386
3387
3388         super_types[mddev->major_version].
3389                 validate_super(mddev, freshest);
3390
3391         i = 0;
3392         rdev_for_each_safe(rdev, tmp, mddev) {
3393                 if (mddev->max_disks &&
3394                     (rdev->desc_nr >= mddev->max_disks ||
3395                      i > mddev->max_disks)) {
3396                         printk(KERN_WARNING
3397                                "md: %s: %s: only %d devices permitted\n",
3398                                mdname(mddev), bdevname(rdev->bdev, b),
3399                                mddev->max_disks);
3400                         kick_rdev_from_array(rdev);
3401                         continue;
3402                 }
3403                 if (rdev != freshest)
3404                         if (super_types[mddev->major_version].
3405                             validate_super(mddev, rdev)) {
3406                                 printk(KERN_WARNING "md: kicking non-fresh %s"
3407                                         " from array!\n",
3408                                         bdevname(rdev->bdev,b));
3409                                 kick_rdev_from_array(rdev);
3410                                 continue;
3411                         }
3412                 if (mddev->level == LEVEL_MULTIPATH) {
3413                         rdev->desc_nr = i++;
3414                         rdev->raid_disk = rdev->desc_nr;
3415                         set_bit(In_sync, &rdev->flags);
3416                 } else if (rdev->raid_disk >= (mddev->raid_disks - min(0, mddev->delta_disks))) {
3417                         rdev->raid_disk = -1;
3418                         clear_bit(In_sync, &rdev->flags);
3419                 }
3420         }
3421 }
3422
3423 /* Read a fixed-point number.
3424  * Numbers in sysfs attributes should be in "standard" units where
3425  * possible, so time should be in seconds.
3426  * However we internally use a a much smaller unit such as
3427  * milliseconds or jiffies.
3428  * This function takes a decimal number with a possible fractional
3429  * component, and produces an integer which is the result of
3430  * multiplying that number by 10^'scale'.
3431  * all without any floating-point arithmetic.
3432  */
3433 int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale)
3434 {
3435         unsigned long result = 0;
3436         long decimals = -1;
3437         while (isdigit(*cp) || (*cp == '.' && decimals < 0)) {
3438                 if (*cp == '.')
3439                         decimals = 0;
3440                 else if (decimals < scale) {
3441                         unsigned int value;
3442                         value = *cp - '0';
3443                         result = result * 10 + value;
3444                         if (decimals >= 0)
3445                                 decimals++;
3446                 }
3447                 cp++;
3448         }
3449         if (*cp == '\n')
3450                 cp++;
3451         if (*cp)
3452                 return -EINVAL;
3453         if (decimals < 0)
3454                 decimals = 0;
3455         while (decimals < scale) {
3456                 result *= 10;
3457                 decimals ++;
3458         }
3459         *res = result;
3460         return 0;
3461 }
3462
3463
3464 static void md_safemode_timeout(unsigned long data);
3465
3466 static ssize_t
3467 safe_delay_show(struct mddev *mddev, char *page)
3468 {
3469         int msec = (mddev->safemode_delay*1000)/HZ;
3470         return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
3471 }
3472 static ssize_t
3473 safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)
3474 {
3475         unsigned long msec;
3476
3477         if (strict_strtoul_scaled(cbuf, &msec, 3) < 0)
3478                 return -EINVAL;
3479         if (msec == 0)
3480                 mddev->safemode_delay = 0;
3481         else {
3482                 unsigned long old_delay = mddev->safemode_delay;
3483                 mddev->safemode_delay = (msec*HZ)/1000;
3484                 if (mddev->safemode_delay == 0)
3485                         mddev->safemode_delay = 1;
3486                 if (mddev->safemode_delay < old_delay)
3487                         md_safemode_timeout((unsigned long)mddev);
3488         }
3489         return len;
3490 }
3491 static struct md_sysfs_entry md_safe_delay =
3492 __ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
3493
3494 static ssize_t
3495 level_show(struct mddev *mddev, char *page)
3496 {
3497         struct md_personality *p = mddev->pers;
3498         if (p)
3499                 return sprintf(page, "%s\n", p->name);
3500         else if (mddev->clevel[0])
3501                 return sprintf(page, "%s\n", mddev->clevel);
3502         else if (mddev->level != LEVEL_NONE)
3503                 return sprintf(page, "%d\n", mddev->level);
3504         else
3505                 return 0;
3506 }
3507
3508 static ssize_t
3509 level_store(struct mddev *mddev, const char *buf, size_t len)
3510 {
3511         char clevel[16];
3512         ssize_t rv = len;
3513         struct md_personality *pers;
3514         long level;
3515         void *priv;
3516         struct md_rdev *rdev;
3517
3518         if (mddev->pers == NULL) {
3519                 if (len == 0)
3520                         return 0;
3521                 if (len >= sizeof(mddev->clevel))
3522                         return -ENOSPC;
3523                 strncpy(mddev->clevel, buf, len);
3524                 if (mddev->clevel[len-1] == '\n')
3525                         len--;
3526                 mddev->clevel[len] = 0;
3527                 mddev->level = LEVEL_NONE;
3528                 return rv;
3529         }
3530
3531         /* request to change the personality.  Need to ensure:
3532          *  - array is not engaged in resync/recovery/reshape
3533          *  - old personality can be suspended
3534          *  - new personality will access other array.
3535          */
3536
3537         if (mddev->sync_thread ||
3538             mddev->reshape_position != MaxSector ||
3539             mddev->sysfs_active)
3540                 return -EBUSY;
3541
3542         if (!mddev->pers->quiesce) {
3543                 printk(KERN_WARNING "md: %s: %s does not support online personality change\n",
3544                        mdname(mddev), mddev->pers->name);
3545                 return -EINVAL;
3546         }
3547
3548         /* Now find the new personality */
3549         if (len == 0 || len >= sizeof(clevel))
3550                 return -EINVAL;
3551         strncpy(clevel, buf, len);
3552         if (clevel[len-1] == '\n')
3553                 len--;
3554         clevel[len] = 0;
3555         if (strict_strtol(clevel, 10, &level))
3556                 level = LEVEL_NONE;
3557
3558         if (request_module("md-%s", clevel) != 0)
3559                 request_module("md-level-%s", clevel);
3560         spin_lock(&pers_lock);
3561         pers = find_pers(level, clevel);
3562         if (!pers || !try_module_get(pers->owner)) {
3563                 spin_unlock(&pers_lock);
3564                 printk(KERN_WARNING "md: personality %s not loaded\n", clevel);
3565                 return -EINVAL;
3566         }
3567         spin_unlock(&pers_lock);
3568
3569         if (pers == mddev->pers) {
3570                 /* Nothing to do! */
3571                 module_put(pers->owner);
3572                 return rv;
3573         }
3574         if (!pers->takeover) {
3575                 module_put(pers->owner);
3576                 printk(KERN_WARNING "md: %s: %s does not support personality takeover\n",
3577                        mdname(mddev), clevel);
3578                 return -EINVAL;
3579         }
3580
3581         rdev_for_each(rdev, mddev)
3582                 rdev->new_raid_disk = rdev->raid_disk;
3583
3584         /* ->takeover must set new_* and/or delta_disks
3585          * if it succeeds, and may set them when it fails.
3586          */
3587         priv = pers->takeover(mddev);
3588         if (IS_ERR(priv)) {
3589                 mddev->new_level = mddev->level;
3590                 mddev->new_layout = mddev->layout;
3591                 mddev->new_chunk_sectors = mddev->chunk_sectors;
3592                 mddev->raid_disks -= mddev->delta_disks;
3593                 mddev->delta_disks = 0;
3594                 mddev->reshape_backwards = 0;
3595                 module_put(pers->owner);
3596                 printk(KERN_WARNING "md: %s: %s would not accept array\n",
3597                        mdname(mddev), clevel);
3598                 return PTR_ERR(priv);
3599         }
3600
3601         /* Looks like we have a winner */
3602         mddev_suspend(mddev);
3603         mddev->pers->stop(mddev);
3604
3605         if (mddev->pers->sync_request == NULL &&
3606             pers->sync_request != NULL) {
3607                 /* need to add the md_redundancy_group */
3608                 if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
3609                         printk(KERN_WARNING
3610                                "md: cannot register extra attributes for %s\n",
3611                                mdname(mddev));
3612                 mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, NULL, "sync_action");
3613         }
3614         if (mddev->pers->sync_request != NULL &&
3615             pers->sync_request == NULL) {
3616                 /* need to remove the md_redundancy_group */
3617                 if (mddev->to_remove == NULL)
3618                         mddev->to_remove = &md_redundancy_group;
3619         }
3620
3621         if (mddev->pers->sync_request == NULL &&
3622             mddev->external) {
3623                 /* We are converting from a no-redundancy array
3624                  * to a redundancy array and metadata is managed
3625                  * externally so we need to be sure that writes
3626                  * won't block due to a need to transition
3627                  *      clean->dirty
3628                  * until external management is started.
3629                  */
3630                 mddev->in_sync = 0;
3631                 mddev->safemode_delay = 0;
3632                 mddev->safemode = 0;
3633         }
3634
3635         rdev_for_each(rdev, mddev) {
3636                 if (rdev->raid_disk < 0)
3637                         continue;
3638                 if (rdev->new_raid_disk >= mddev->raid_disks)
3639                         rdev->new_raid_disk = -1;
3640                 if (rdev->new_raid_disk == rdev->raid_disk)
3641                         continue;
3642                 sysfs_unlink_rdev(mddev, rdev);
3643         }
3644         rdev_for_each(rdev, mddev) {
3645                 if (rdev->raid_disk < 0)
3646                         continue;
3647                 if (rdev->new_raid_disk == rdev->raid_disk)
3648                         continue;
3649                 rdev->raid_disk = rdev->new_raid_disk;
3650                 if (rdev->raid_disk < 0)
3651                         clear_bit(In_sync, &rdev->flags);
3652                 else {
3653                         if (sysfs_link_rdev(mddev, rdev))
3654                                 printk(KERN_WARNING "md: cannot register rd%d"
3655                                        " for %s after level change\n",
3656                                        rdev->raid_disk, mdname(mddev));
3657                 }
3658         }
3659
3660         module_put(mddev->pers->owner);
3661         mddev->pers = pers;
3662         mddev->private = priv;
3663         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
3664         mddev->level = mddev->new_level;
3665         mddev->layout = mddev->new_layout;
3666         mddev->chunk_sectors = mddev->new_chunk_sectors;
3667         mddev->delta_disks = 0;
3668         mddev->reshape_backwards = 0;
3669         mddev->degraded = 0;
3670         if (mddev->pers->sync_request == NULL) {
3671                 /* this is now an array without redundancy, so
3672                  * it must always be in_sync
3673                  */
3674                 mddev->in_sync = 1;
3675                 del_timer_sync(&mddev->safemode_timer);
3676         }
3677         pers->run(mddev);
3678         set_bit(MD_CHANGE_DEVS, &mddev->flags);
3679         mddev_resume(mddev);
3680         sysfs_notify(&mddev->kobj, NULL, "level");
3681         md_new_event(mddev);
3682         return rv;
3683 }
3684
3685 static struct md_sysfs_entry md_level =
3686 __ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
3687
3688
3689 static ssize_t
3690 layout_show(struct mddev *mddev, char *page)
3691 {
3692         /* just a number, not meaningful for all levels */
3693         if (mddev->reshape_position != MaxSector &&
3694             mddev->layout != mddev->new_layout)
3695                 return sprintf(page, "%d (%d)\n",
3696                                mddev->new_layout, mddev->layout);
3697         return sprintf(page, "%d\n", mddev->layout);
3698 }
3699
3700 static ssize_t
3701 layout_store(struct mddev *mddev, const char *buf, size_t len)
3702 {
3703         char *e;
3704         unsigned long n = simple_strtoul(buf, &e, 10);
3705
3706         if (!*buf || (*e && *e != '\n'))
3707                 return -EINVAL;
3708
3709         if (mddev->pers) {
3710                 int err;
3711                 if (mddev->pers->check_reshape == NULL)
3712                         return -EBUSY;
3713                 mddev->new_layout = n;
3714                 err = mddev->pers->check_reshape(mddev);
3715                 if (err) {
3716                         mddev->new_layout = mddev->layout;
3717                         return err;
3718                 }
3719         } else {
3720                 mddev->new_layout = n;
3721                 if (mddev->reshape_position == MaxSector)
3722                         mddev->layout = n;
3723         }
3724         return len;
3725 }
3726 static struct md_sysfs_entry md_layout =
3727 __ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
3728
3729
3730 static ssize_t
3731 raid_disks_show(struct mddev *mddev, char *page)
3732 {
3733         if (mddev->raid_disks == 0)
3734                 return 0;
3735         if (mddev->reshape_position != MaxSector &&
3736             mddev->delta_disks != 0)
3737                 return sprintf(page, "%d (%d)\n", mddev->raid_disks,
3738                                mddev->raid_disks - mddev->delta_disks);
3739         return sprintf(page, "%d\n", mddev->raid_disks);
3740 }
3741
3742 static int update_raid_disks(struct mddev *mddev, int raid_disks);
3743
3744 static ssize_t
3745 raid_disks_store(struct mddev *mddev, const char *buf, size_t len)
3746 {
3747         char *e;
3748         int rv = 0;
3749         unsigned long n = simple_strtoul(buf, &e, 10);
3750
3751         if (!*buf || (*e && *e != '\n'))
3752                 return -EINVAL;
3753
3754         if (mddev->pers)
3755                 rv = update_raid_disks(mddev, n);
3756         else if (mddev->reshape_position != MaxSector) {
3757                 struct md_rdev *rdev;
3758                 int olddisks = mddev->raid_disks - mddev->delta_disks;
3759
3760                 rdev_for_each(rdev, mddev) {
3761                         if (olddisks < n &&
3762                             rdev->data_offset < rdev->new_data_offset)
3763                                 return -EINVAL;
3764                         if (olddisks > n &&
3765                             rdev->data_offset > rdev->new_data_offset)
3766                                 return -EINVAL;
3767                 }
3768                 mddev->delta_disks = n - olddisks;
3769                 mddev->raid_disks = n;
3770                 mddev->reshape_backwards = (mddev->delta_disks < 0);
3771         } else
3772                 mddev->raid_disks = n;
3773         return rv ? rv : len;
3774 }
3775 static struct md_sysfs_entry md_raid_disks =
3776 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
3777
3778 static ssize_t
3779 chunk_size_show(struct mddev *mddev, char *page)
3780 {
3781         if (mddev->reshape_position != MaxSector &&
3782             mddev->chunk_sectors != mddev->new_chunk_sectors)
3783                 return sprintf(page, "%d (%d)\n",
3784                                mddev->new_chunk_sectors << 9,
3785                                mddev->chunk_sectors << 9);
3786         return sprintf(page, "%d\n", mddev->chunk_sectors << 9);
3787 }
3788
3789 static ssize_t
3790 chunk_size_store(struct mddev *mddev, const char *buf, size_t len)
3791 {
3792         char *e;
3793         unsigned long n = simple_strtoul(buf, &e, 10);
3794
3795         if (!*buf || (*e && *e != '\n'))
3796                 return -EINVAL;
3797
3798         if (mddev->pers) {
3799                 int err;
3800                 if (mddev->pers->check_reshape == NULL)
3801                         return -EBUSY;
3802                 mddev->new_chunk_sectors = n >> 9;
3803                 err = mddev->pers->check_reshape(mddev);
3804                 if (err) {
3805                         mddev->new_chunk_sectors = mddev->chunk_sectors;
3806                         return err;
3807                 }
3808         } else {
3809                 mddev->new_chunk_sectors = n >> 9;
3810                 if (mddev->reshape_position == MaxSector)
3811                         mddev->chunk_sectors = n >> 9;
3812         }
3813         return len;
3814 }
3815 static struct md_sysfs_entry md_chunk_size =
3816 __ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
3817
3818 static ssize_t
3819 resync_start_show(struct mddev *mddev, char *page)
3820 {
3821         if (mddev->recovery_cp == MaxSector)
3822                 return sprintf(page, "none\n");
3823         return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
3824 }
3825
3826 static ssize_t
3827 resync_start_store(struct mddev *mddev, const char *buf, size_t len)
3828 {
3829         char *e;
3830         unsigned long long n = simple_strtoull(buf, &e, 10);
3831
3832         if (mddev->pers && !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
3833                 return -EBUSY;
3834         if (cmd_match(buf, "none"))
3835                 n = MaxSector;
3836         else if (!*buf || (*e && *e != '\n'))
3837                 return -EINVAL;
3838
3839         mddev->recovery_cp = n;
3840         return len;
3841 }
3842 static struct md_sysfs_entry md_resync_start =
3843 __ATTR(resync_start, S_IRUGO|S_IWUSR, resync_start_show, resync_start_store);
3844
3845 /*
3846  * The array state can be:
3847  *
3848  * clear
3849  *     No devices, no size, no level
3850  *     Equivalent to STOP_ARRAY ioctl
3851  * inactive
3852  *     May have some settings, but array is not active
3853  *        all IO results in error
3854  *     When written, doesn't tear down array, but just stops it
3855  * suspended (not supported yet)
3856  *     All IO requests will block. The array can be reconfigured.
3857  *     Writing this, if accepted, will block until array is quiescent
3858  * readonly
3859  *     no resync can happen.  no superblocks get written.
3860  *     write requests fail
3861  * read-auto
3862  *     like readonly, but behaves like 'clean' on a write request.
3863  *
3864  * clean - no pending writes, but otherwise active.
3865  *     When written to inactive array, starts without resync
3866  *     If a write request arrives then
3867  *       if metadata is known, mark 'dirty' and switch to 'active'.
3868  *       if not known, block and switch to write-pending
3869  *     If written to an active array that has pending writes, then fails.
3870  * active
3871  *     fully active: IO and resync can be happening.
3872  *     When written to inactive array, starts with resync
3873  *
3874  * write-pending
3875  *     clean, but writes are blocked waiting for 'active' to be written.
3876  *
3877  * active-idle
3878  *     like active, but no writes have been seen for a while (100msec).
3879  *
3880  */
3881 enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
3882                    write_pending, active_idle, bad_word};
3883 static char *array_states[] = {
3884         "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
3885         "write-pending", "active-idle", NULL };
3886
3887 static int match_word(const char *word, char **list)
3888 {
3889         int n;
3890         for (n=0; list[n]; n++)
3891                 if (cmd_match(word, list[n]))
3892                         break;
3893         return n;
3894 }
3895
3896 static ssize_t
3897 array_state_show(struct mddev *mddev, char *page)
3898 {
3899         enum array_state st = inactive;
3900
3901         if (mddev->pers)
3902                 switch(mddev->ro) {
3903                 case 1:
3904                         st = readonly;
3905                         break;
3906                 case 2:
3907                         st = read_auto;
3908                         break;
3909                 case 0:
3910                         if (mddev->in_sync)
3911                                 st = clean;
3912                         else if (test_bit(MD_CHANGE_PENDING, &mddev->flags))
3913                                 st = write_pending;
3914                         else if (mddev->safemode)
3915                                 st = active_idle;
3916                         else
3917                                 st = active;
3918                 }
3919         else {
3920                 if (list_empty(&mddev->disks) &&
3921                     mddev->raid_disks == 0 &&
3922                     mddev->dev_sectors == 0)
3923                         st = clear;
3924                 else
3925                         st = inactive;
3926         }
3927         return sprintf(page, "%s\n", array_states[st]);
3928 }
3929
3930 static int do_md_stop(struct mddev * mddev, int ro, struct block_device *bdev);
3931 static int md_set_readonly(struct mddev * mddev, struct block_device *bdev);
3932 static int do_md_run(struct mddev * mddev);
3933 static int restart_array(struct mddev *mddev);
3934
3935 static ssize_t
3936 array_state_store(struct mddev *mddev, const char *buf, size_t len)
3937 {
3938         int err = -EINVAL;
3939         enum array_state st = match_word(buf, array_states);
3940         switch(st) {
3941         case bad_word:
3942                 break;
3943         case clear:
3944                 /* stopping an active array */
3945                 err = do_md_stop(mddev, 0, NULL);
3946                 break;
3947         case inactive:
3948                 /* stopping an active array */
3949                 if (mddev->pers)
3950                         err = do_md_stop(mddev, 2, NULL);
3951                 else
3952                         err = 0; /* already inactive */
3953                 break;
3954         case suspended:
3955                 break; /* not supported yet */
3956         case readonly:
3957                 if (mddev->pers)
3958                         err = md_set_readonly(mddev, NULL);
3959                 else {
3960                         mddev->ro = 1;
3961                         set_disk_ro(mddev->gendisk, 1);
3962                         err = do_md_run(mddev);
3963                 }
3964                 break;
3965         case read_auto:
3966                 if (mddev->pers) {
3967                         if (mddev->ro == 0)
3968                                 err = md_set_readonly(mddev, NULL);
3969                         else if (mddev->ro == 1)
3970                                 err = restart_array(mddev);
3971                         if (err == 0) {
3972                                 mddev->ro = 2;
3973                                 set_disk_ro(mddev->gendisk, 0);
3974                         }
3975                 } else {
3976                         mddev->ro = 2;
3977                         err = do_md_run(mddev);
3978                 }
3979                 break;
3980         case clean:
3981                 if (mddev->pers) {
3982                         restart_array(mddev);
3983                         spin_lock_irq(&mddev->write_lock);
3984                         if (atomic_read(&mddev->writes_pending) == 0) {
3985                                 if (mddev->in_sync == 0) {
3986                                         mddev->in_sync = 1;
3987                                         if (mddev->safemode == 1)
3988                                                 mddev->safemode = 0;
3989                                         set_bit(MD_CHANGE_CLEAN, &mddev->flags);
3990                                 }
3991                                 err = 0;
3992                         } else
3993                                 err = -EBUSY;
3994                         spin_unlock_irq(&mddev->write_lock);
3995                 } else
3996                         err = -EINVAL;
3997                 break;
3998         case active:
3999                 if (mddev->pers) {
4000                         restart_array(mddev);
4001                         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
4002                         wake_up(&mddev->sb_wait);
4003                         err = 0;
4004                 } else {
4005                         mddev->ro = 0;
4006                         set_disk_ro(mddev->gendisk, 0);
4007                         err = do_md_run(mddev);
4008                 }
4009                 break;
4010         case write_pending:
4011         case active_idle:
4012                 /* these cannot be set */
4013                 break;
4014         }
4015         if (err)
4016                 return err;
4017         else {
4018                 if (mddev->hold_active == UNTIL_IOCTL)
4019                         mddev->hold_active = 0;
4020                 sysfs_notify_dirent_safe(mddev->sysfs_state);
4021                 return len;
4022         }
4023 }
4024 static struct md_sysfs_entry md_array_state =
4025 __ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
4026
4027 static ssize_t
4028 max_corrected_read_errors_show(struct mddev *mddev, char *page) {
4029         return sprintf(page, "%d\n",
4030                        atomic_read(&mddev->max_corr_read_errors));
4031 }
4032
4033 static ssize_t
4034 max_corrected_read_errors_store(struct mddev *mddev, const char *buf, size_t len)
4035 {
4036         char *e;
4037         unsigned long n = simple_strtoul(buf, &e, 10);
4038
4039         if (*buf && (*e == 0 || *e == '\n')) {
4040                 atomic_set(&mddev->max_corr_read_errors, n);
4041                 return len;
4042         }
4043         return -EINVAL;
4044 }
4045
4046 static struct md_sysfs_entry max_corr_read_errors =
4047 __ATTR(max_read_errors, S_IRUGO|S_IWUSR, max_corrected_read_errors_show,
4048         max_corrected_read_errors_store);
4049
4050 static ssize_t
4051 null_show(struct mddev *mddev, char *page)
4052 {
4053         return -EINVAL;
4054 }
4055
4056 static ssize_t
4057 new_dev_store(struct mddev *mddev, const char *buf, size_t len)
4058 {
4059         /* buf must be %d:%d\n? giving major and minor numbers */
4060         /* The new device is added to the array.
4061          * If the array has a persistent superblock, we read the
4062          * superblock to initialise info and check validity.
4063          * Otherwise, only checking done is that in bind_rdev_to_array,
4064          * which mainly checks size.
4065          */
4066         char *e;
4067         int major = simple_strtoul(buf, &e, 10);
4068         int minor;
4069         dev_t dev;
4070         struct md_rdev *rdev;
4071         int err;
4072
4073         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
4074                 return -EINVAL;
4075         minor = simple_strtoul(e+1, &e, 10);
4076         if (*e && *e != '\n')
4077                 return -EINVAL;
4078         dev = MKDEV(major, minor);
4079         if (major != MAJOR(dev) ||
4080             minor != MINOR(dev))
4081                 return -EOVERFLOW;
4082
4083
4084         if (mddev->persistent) {
4085                 rdev = md_import_device(dev, mddev->major_version,
4086                                         mddev->minor_version);
4087                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
4088                         struct md_rdev *rdev0
4089                                 = list_entry(mddev->disks.next,
4090                                              struct md_rdev, same_set);
4091                         err = super_types[mddev->major_version]
4092                                 .load_super(rdev, rdev0, mddev->minor_version);
4093                         if (err < 0)
4094                                 goto out;
4095                 }
4096         } else if (mddev->external)
4097                 rdev = md_import_device(dev, -2, -1);
4098         else
4099                 rdev = md_import_device(dev, -1, -1);
4100
4101         if (IS_ERR(rdev))
4102                 return PTR_ERR(rdev);
4103         err = bind_rdev_to_array(rdev, mddev);
4104  out:
4105         if (err)
4106                 export_rdev(rdev);
4107         return err ? err : len;
4108 }
4109
4110 static struct md_sysfs_entry md_new_device =
4111 __ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
4112
4113 static ssize_t
4114 bitmap_store(struct mddev *mddev, const char *buf, size_t len)
4115 {
4116         char *end;
4117         unsigned long chunk, end_chunk;
4118
4119         if (!mddev->bitmap)
4120                 goto out;
4121         /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
4122         while (*buf) {
4123                 chunk = end_chunk = simple_strtoul(buf, &end, 0);
4124                 if (buf == end) break;
4125                 if (*end == '-') { /* range */
4126                         buf = end + 1;
4127                         end_chunk = simple_strtoul(buf, &end, 0);
4128                         if (buf == end) break;
4129                 }
4130                 if (*end && !isspace(*end)) break;
4131                 bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
4132                 buf = skip_spaces(end);
4133         }
4134         bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
4135 out:
4136         return len;
4137 }
4138
4139 static struct md_sysfs_entry md_bitmap =
4140 __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
4141
4142 static ssize_t
4143 size_show(struct mddev *mddev, char *page)
4144 {
4145         return sprintf(page, "%llu\n",
4146                 (unsigned long long)mddev->dev_sectors / 2);
4147 }
4148
4149 static int update_size(struct mddev *mddev, sector_t num_sectors);
4150
4151 static ssize_t
4152 size_store(struct mddev *mddev, const char *buf, size_t len)
4153 {
4154         /* If array is inactive, we can reduce the component size, but
4155          * not increase it (except from 0).
4156          * If array is active, we can try an on-line resize
4157          */
4158         sector_t sectors;
4159         int err = strict_blocks_to_sectors(buf, &sectors);
4160
4161         if (err < 0)
4162                 return err;
4163         if (mddev->pers) {
4164                 err = update_size(mddev, sectors);
4165                 md_update_sb(mddev, 1);
4166         } else {
4167                 if (mddev->dev_sectors == 0 ||
4168                     mddev->dev_sectors > sectors)
4169                         mddev->dev_sectors = sectors;
4170                 else
4171                         err = -ENOSPC;
4172         }
4173         return err ? err : len;
4174 }
4175
4176 static struct md_sysfs_entry md_size =
4177 __ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
4178
4179
4180 /* Metdata version.
4181  * This is one of
4182  *   'none' for arrays with no metadata (good luck...)
4183  *   'external' for arrays with externally managed metadata,
4184  * or N.M for internally known formats
4185  */
4186 static ssize_t
4187 metadata_show(struct mddev *mddev, char *page)
4188 {
4189         if (mddev->persistent)
4190                 return sprintf(page, "%d.%d\n",
4191                                mddev->major_version, mddev->minor_version);
4192         else if (mddev->external)
4193                 return sprintf(page, "external:%s\n", mddev->metadata_type);
4194         else
4195                 return sprintf(page, "none\n");
4196 }
4197
4198 static ssize_t
4199 metadata_store(struct mddev *mddev, const char *buf, size_t len)
4200 {
4201         int major, minor;
4202         char *e;
4203         /* Changing the details of 'external' metadata is
4204          * always permitted.  Otherwise there must be
4205          * no devices attached to the array.
4206          */
4207         if (mddev->external && strncmp(buf, "external:", 9) == 0)
4208                 ;
4209         else if (!list_empty(&mddev->disks))
4210                 return -EBUSY;
4211
4212         if (cmd_match(buf, "none")) {
4213                 mddev->persistent = 0;
4214                 mddev->external = 0;
4215                 mddev->major_version = 0;
4216                 mddev->minor_version = 90;
4217                 return len;
4218         }
4219         if (strncmp(buf, "external:", 9) == 0) {
4220                 size_t namelen = len-9;
4221                 if (namelen >= sizeof(mddev->metadata_type))
4222                         namelen = sizeof(mddev->metadata_type)-1;
4223                 strncpy(mddev->metadata_type, buf+9, namelen);
4224                 mddev->metadata_type[namelen] = 0;
4225                 if (namelen && mddev->metadata_type[namelen-1] == '\n')
4226                         mddev->metadata_type[--namelen] = 0;
4227                 mddev->persistent = 0;
4228                 mddev->external = 1;
4229                 mddev->major_version = 0;
4230                 mddev->minor_version = 90;
4231                 return len;
4232         }
4233         major = simple_strtoul(buf, &e, 10);
4234         if (e==buf || *e != '.')
4235                 return -EINVAL;
4236         buf = e+1;
4237         minor = simple_strtoul(buf, &e, 10);
4238         if (e==buf || (*e && *e != '\n') )
4239                 return -EINVAL;
4240         if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
4241                 return -ENOENT;
4242         mddev->major_version = major;
4243         mddev->minor_version = minor;
4244         mddev->persistent = 1;
4245         mddev->external = 0;
4246         return len;
4247 }
4248
4249 static struct md_sysfs_entry md_metadata =
4250 __ATTR(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
4251
4252 static ssize_t
4253 action_show(struct mddev *mddev, char *page)
4254 {
4255         char *type = "idle";
4256         if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
4257                 type = "frozen";
4258         else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
4259             (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
4260                 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
4261                         type = "reshape";
4262                 else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
4263                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
4264                                 type = "resync";
4265                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
4266                                 type = "check";
4267                         else
4268                                 type = "repair";
4269                 } else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
4270                         type = "recover";
4271         }
4272         return sprintf(page, "%s\n", type);
4273 }
4274
4275 static void reap_sync_thread(struct mddev *mddev);
4276
4277 static ssize_t
4278 action_store(struct mddev *mddev, const char *page, size_t len)
4279 {
4280         if (!mddev->pers || !mddev->pers->sync_request)
4281                 return -EINVAL;
4282
4283         if (cmd_match(page, "frozen"))
4284                 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4285         else
4286                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4287
4288         if (cmd_match(page, "idle") || cmd_match(page, "frozen")) {
4289                 if (mddev->sync_thread) {
4290                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4291                         reap_sync_thread(mddev);
4292                 }
4293         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
4294                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
4295                 return -EBUSY;
4296         else if (cmd_match(page, "resync"))
4297                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4298         else if (cmd_match(page, "recover")) {
4299                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
4300                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4301         } else if (cmd_match(page, "reshape")) {
4302                 int err;
4303                 if (mddev->pers->start_reshape == NULL)
4304                         return -EINVAL;
4305                 err = mddev->pers->start_reshape(mddev);
4306                 if (err)
4307                         return err;
4308                 sysfs_notify(&mddev->kobj, NULL, "degraded");
4309         } else {
4310                 if (cmd_match(page, "check"))
4311                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
4312                 else if (!cmd_match(page, "repair"))
4313                         return -EINVAL;
4314                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
4315                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4316         }
4317         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4318         md_wakeup_thread(mddev->thread);
4319         sysfs_notify_dirent_safe(mddev->sysfs_action);
4320         return len;
4321 }
4322
4323 static ssize_t
4324 mismatch_cnt_show(struct mddev *mddev, char *page)
4325 {
4326         return sprintf(page, "%llu\n",
4327                        (unsigned long long) mddev->resync_mismatches);
4328 }
4329
4330 static struct md_sysfs_entry md_scan_mode =
4331 __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
4332
4333
4334 static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
4335
4336 static ssize_t
4337 sync_min_show(struct mddev *mddev, char *page)
4338 {
4339         return sprintf(page, "%d (%s)\n", speed_min(mddev),
4340                        mddev->sync_speed_min ? "local": "system");
4341 }
4342
4343 static ssize_t
4344 sync_min_store(struct mddev *mddev, const char *buf, size_t len)
4345 {
4346         int min;
4347         char *e;
4348         if (strncmp(buf, "system", 6)==0) {
4349                 mddev->sync_speed_min = 0;
4350                 return len;
4351         }
4352         min = simple_strtoul(buf, &e, 10);
4353         if (buf == e || (*e && *e != '\n') || min <= 0)
4354                 return -EINVAL;
4355         mddev->sync_speed_min = min;
4356         return len;
4357 }
4358
4359 static struct md_sysfs_entry md_sync_min =
4360 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
4361
4362 static ssize_t
4363 sync_max_show(struct mddev *mddev, char *page)
4364 {
4365         return sprintf(page, "%d (%s)\n", speed_max(mddev),
4366                        mddev->sync_speed_max ? "local": "system");
4367 }
4368
4369 static ssize_t
4370 sync_max_store(struct mddev *mddev, const char *buf, size_t len)
4371 {
4372         int max;
4373         char *e;
4374         if (strncmp(buf, "system", 6)==0) {
4375                 mddev->sync_speed_max = 0;
4376                 return len;
4377         }
4378         max = simple_strtoul(buf, &e, 10);
4379         if (buf == e || (*e && *e != '\n') || max <= 0)
4380                 return -EINVAL;
4381         mddev->sync_speed_max = max;
4382         return len;
4383 }
4384
4385 static struct md_sysfs_entry md_sync_max =
4386 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
4387
4388 static ssize_t
4389 degraded_show(struct mddev *mddev, char *page)
4390 {
4391         return sprintf(page, "%d\n", mddev->degraded);
4392 }
4393 static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
4394
4395 static ssize_t
4396 sync_force_parallel_show(struct mddev *mddev, char *page)
4397 {
4398         return sprintf(page, "%d\n", mddev->parallel_resync);
4399 }
4400
4401 static ssize_t
4402 sync_force_parallel_store(struct mddev *mddev, const char *buf, size_t len)
4403 {
4404         long n;
4405
4406         if (strict_strtol(buf, 10, &n))
4407                 return -EINVAL;
4408
4409         if (n != 0 && n != 1)
4410                 return -EINVAL;
4411
4412         mddev->parallel_resync = n;
4413
4414         if (mddev->sync_thread)
4415                 wake_up(&resync_wait);
4416
4417         return len;
4418 }
4419
4420 /* force parallel resync, even with shared block devices */
4421 static struct md_sysfs_entry md_sync_force_parallel =
4422 __ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
4423        sync_force_parallel_show, sync_force_parallel_store);
4424
4425 static ssize_t
4426 sync_speed_show(struct mddev *mddev, char *page)
4427 {
4428         unsigned long resync, dt, db;
4429         if (mddev->curr_resync == 0)
4430                 return sprintf(page, "none\n");
4431         resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
4432         dt = (jiffies - mddev->resync_mark) / HZ;
4433         if (!dt) dt++;
4434         db = resync - mddev->resync_mark_cnt;
4435         return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
4436 }
4437
4438 static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
4439
4440 static ssize_t
4441 sync_completed_show(struct mddev *mddev, char *page)
4442 {
4443         unsigned long long max_sectors, resync;
4444
4445         if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4446                 return sprintf(page, "none\n");
4447
4448         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
4449             test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
4450                 max_sectors = mddev->resync_max_sectors;
4451         else
4452                 max_sectors = mddev->dev_sectors;
4453
4454         resync = mddev->curr_resync_completed;
4455         return sprintf(page, "%llu / %llu\n", resync, max_sectors);
4456 }
4457
4458 static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
4459
4460 static ssize_t
4461 min_sync_show(struct mddev *mddev, char *page)
4462 {
4463         return sprintf(page, "%llu\n",
4464                        (unsigned long long)mddev->resync_min);
4465 }
4466 static ssize_t
4467 min_sync_store(struct mddev *mddev, const char *buf, size_t len)
4468 {
4469         unsigned long long min;
4470         if (strict_strtoull(buf, 10, &min))
4471                 return -EINVAL;
4472         if (min > mddev->resync_max)
4473                 return -EINVAL;
4474         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4475                 return -EBUSY;
4476
4477         /* Must be a multiple of chunk_size */
4478         if (mddev->chunk_sectors) {
4479                 sector_t temp = min;
4480                 if (sector_div(temp, mddev->chunk_sectors))
4481                         return -EINVAL;
4482         }
4483         mddev->resync_min = min;
4484
4485         return len;
4486 }
4487
4488 static struct md_sysfs_entry md_min_sync =
4489 __ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
4490
4491 static ssize_t
4492 max_sync_show(struct mddev *mddev, char *page)
4493 {
4494         if (mddev->resync_max == MaxSector)
4495                 return sprintf(page, "max\n");
4496         else
4497                 return sprintf(page, "%llu\n",
4498                                (unsigned long long)mddev->resync_max);
4499 }
4500 static ssize_t
4501 max_sync_store(struct mddev *mddev, const char *buf, size_t len)
4502 {
4503         if (strncmp(buf, "max", 3) == 0)
4504                 mddev->resync_max = MaxSector;
4505         else {
4506                 unsigned long long max;
4507                 if (strict_strtoull(buf, 10, &max))
4508                         return -EINVAL;
4509                 if (max < mddev->resync_min)
4510                         return -EINVAL;
4511                 if (max < mddev->resync_max &&
4512                     mddev->ro == 0 &&
4513                     test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4514                         return -EBUSY;
4515
4516                 /* Must be a multiple of chunk_size */
4517                 if (mddev->chunk_sectors) {
4518                         sector_t temp = max;
4519                         if (sector_div(temp, mddev->chunk_sectors))
4520                                 return -EINVAL;
4521                 }
4522                 mddev->resync_max = max;
4523         }
4524         wake_up(&mddev->recovery_wait);
4525         return len;
4526 }
4527
4528 static struct md_sysfs_entry md_max_sync =
4529 __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
4530
4531 static ssize_t
4532 suspend_lo_show(struct mddev *mddev, char *page)
4533 {
4534         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
4535 }
4536
4537 static ssize_t
4538 suspend_lo_store(struct mddev *mddev, const char *buf, size_t len)
4539 {
4540         char *e;
4541         unsigned long long new = simple_strtoull(buf, &e, 10);
4542         unsigned long long old = mddev->suspend_lo;
4543
4544         if (mddev->pers == NULL ||
4545             mddev->pers->quiesce == NULL)
4546                 return -EINVAL;
4547         if (buf == e || (*e && *e != '\n'))
4548                 return -EINVAL;
4549
4550         mddev->suspend_lo = new;
4551         if (new >= old)
4552                 /* Shrinking suspended region */
4553                 mddev->pers->quiesce(mddev, 2);
4554         else {
4555                 /* Expanding suspended region - need to wait */
4556                 mddev->pers->quiesce(mddev, 1);
4557                 mddev->pers->quiesce(mddev, 0);
4558         }
4559         return len;
4560 }
4561 static struct md_sysfs_entry md_suspend_lo =
4562 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
4563
4564
4565 static ssize_t
4566 suspend_hi_show(struct mddev *mddev, char *page)
4567 {
4568         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
4569 }
4570
4571 static ssize_t
4572 suspend_hi_store(struct mddev *mddev, const char *buf, size_t len)
4573 {
4574         char *e;
4575         unsigned long long new = simple_strtoull(buf, &e, 10);
4576         unsigned long long old = mddev->suspend_hi;
4577
4578         if (mddev->pers == NULL ||
4579             mddev->pers->quiesce == NULL)
4580                 return -EINVAL;
4581         if (buf == e || (*e && *e != '\n'))
4582                 return -EINVAL;
4583
4584         mddev->suspend_hi = new;
4585         if (new <= old)
4586                 /* Shrinking suspended region */
4587                 mddev->pers->quiesce(mddev, 2);
4588         else {
4589                 /* Expanding suspended region - need to wait */
4590                 mddev->pers->quiesce(mddev, 1);
4591                 mddev->pers->quiesce(mddev, 0);
4592         }
4593         return len;
4594 }
4595 static struct md_sysfs_entry md_suspend_hi =
4596 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
4597
4598 static ssize_t
4599 reshape_position_show(struct mddev *mddev, char *page)
4600 {
4601         if (mddev->reshape_position != MaxSector)
4602                 return sprintf(page, "%llu\n",
4603                                (unsigned long long)mddev->reshape_position);
4604         strcpy(page, "none\n");
4605         return 5;
4606 }
4607
4608 static ssize_t
4609 reshape_position_store(struct mddev *mddev, const char *buf, size_t len)
4610 {
4611         struct md_rdev *rdev;
4612         char *e;
4613         unsigned long long new = simple_strtoull(buf, &e, 10);
4614         if (mddev->pers)
4615                 return -EBUSY;
4616         if (buf == e || (*e && *e != '\n'))
4617                 return -EINVAL;
4618         mddev->reshape_position = new;
4619         mddev->delta_disks = 0;
4620         mddev->reshape_backwards = 0;
4621         mddev->new_level = mddev->level;
4622         mddev->new_layout = mddev->layout;
4623         mddev->new_chunk_sectors = mddev->chunk_sectors;
4624         rdev_for_each(rdev, mddev)
4625                 rdev->new_data_offset = rdev->data_offset;
4626         return len;
4627 }
4628
4629 static struct md_sysfs_entry md_reshape_position =
4630 __ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
4631        reshape_position_store);
4632
4633 static ssize_t
4634 reshape_direction_show(struct mddev *mddev, char *page)
4635 {
4636         return sprintf(page, "%s\n",
4637                        mddev->reshape_backwards ? "backwards" : "forwards");
4638 }
4639
4640 static ssize_t
4641 reshape_direction_store(struct mddev *mddev, const char *buf, size_t len)
4642 {
4643         int backwards = 0;
4644         if (cmd_match(buf, "forwards"))
4645                 backwards = 0;
4646         else if (cmd_match(buf, "backwards"))
4647                 backwards = 1;
4648         else
4649                 return -EINVAL;
4650         if (mddev->reshape_backwards == backwards)
4651                 return len;
4652
4653         /* check if we are allowed to change */
4654         if (mddev->delta_disks)
4655                 return -EBUSY;
4656
4657         if (mddev->persistent &&
4658             mddev->major_version == 0)
4659                 return -EINVAL;
4660
4661         mddev->reshape_backwards = backwards;
4662         return len;
4663 }
4664
4665 static struct md_sysfs_entry md_reshape_direction =
4666 __ATTR(reshape_direction, S_IRUGO|S_IWUSR, reshape_direction_show,
4667        reshape_direction_store);
4668
4669 static ssize_t
4670 array_size_show(struct mddev *mddev, char *page)
4671 {
4672         if (mddev->external_size)
4673                 return sprintf(page, "%llu\n",
4674                                (unsigned long long)mddev->array_sectors/2);
4675         else
4676                 return sprintf(page, "default\n");
4677 }
4678
4679 static ssize_t
4680 array_size_store(struct mddev *mddev, const char *buf, size_t len)
4681 {
4682         sector_t sectors;
4683
4684         if (strncmp(buf, "default", 7) == 0) {
4685                 if (mddev->pers)
4686                         sectors = mddev->pers->size(mddev, 0, 0);
4687                 else
4688                         sectors = mddev->array_sectors;
4689
4690                 mddev->external_size = 0;
4691         } else {
4692                 if (strict_blocks_to_sectors(buf, &sectors) < 0)
4693                         return -EINVAL;
4694                 if (mddev->pers && mddev->pers->size(mddev, 0, 0) < sectors)
4695                         return -E2BIG;
4696
4697                 mddev->external_size = 1;
4698         }
4699
4700         mddev->array_sectors = sectors;
4701         if (mddev->pers) {
4702                 set_capacity(mddev->gendisk, mddev->array_sectors);
4703                 revalidate_disk(mddev->gendisk);
4704         }
4705         return len;
4706 }
4707
4708 static struct md_sysfs_entry md_array_size =
4709 __ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show,
4710        array_size_store);
4711
4712 static struct attribute *md_default_attrs[] = {
4713         &md_level.attr,
4714         &md_layout.attr,
4715         &md_raid_disks.attr,
4716         &md_chunk_size.attr,
4717         &md_size.attr,
4718         &md_resync_start.attr,
4719         &md_metadata.attr,
4720         &md_new_device.attr,
4721         &md_safe_delay.attr,
4722         &md_array_state.attr,
4723         &md_reshape_position.attr,
4724         &md_reshape_direction.attr,
4725         &md_array_size.attr,
4726         &max_corr_read_errors.attr,
4727         NULL,
4728 };
4729
4730 static struct attribute *md_redundancy_attrs[] = {
4731         &md_scan_mode.attr,
4732         &md_mismatches.attr,
4733         &md_sync_min.attr,
4734         &md_sync_max.attr,
4735         &md_sync_speed.attr,
4736         &md_sync_force_parallel.attr,
4737         &md_sync_completed.attr,
4738         &md_min_sync.attr,
4739         &md_max_sync.attr,
4740         &md_suspend_lo.attr,
4741         &md_suspend_hi.attr,
4742         &md_bitmap.attr,
4743         &md_degraded.attr,
4744         NULL,
4745 };
4746 static struct attribute_group md_redundancy_group = {
4747         .name = NULL,
4748         .attrs = md_redundancy_attrs,
4749 };
4750
4751
4752 static ssize_t
4753 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
4754 {
4755         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
4756         struct mddev *mddev = container_of(kobj, struct mddev, kobj);
4757         ssize_t rv;
4758
4759         if (!entry->show)
4760                 return -EIO;
4761         spin_lock(&all_mddevs_lock);
4762         if (list_empty(&mddev->all_mddevs)) {
4763                 spin_unlock(&all_mddevs_lock);
4764                 return -EBUSY;
4765         }
4766         mddev_get(mddev);
4767         spin_unlock(&all_mddevs_lock);
4768
4769         rv = mddev_lock(mddev);
4770         if (!rv) {
4771                 rv = entry->show(mddev, page);
4772                 mddev_unlock(mddev);
4773         }
4774         mddev_put(mddev);
4775         return rv;
4776 }
4777
4778 static ssize_t
4779 md_attr_store(struct kobject *kobj, struct attribute *attr,
4780               const char *page, size_t length)
4781 {
4782         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
4783         struct mddev *mddev = container_of(kobj, struct mddev, kobj);
4784         ssize_t rv;
4785
4786         if (!entry->store)
4787                 return -EIO;
4788         if (!capable(CAP_SYS_ADMIN))
4789                 return -EACCES;
4790         spin_lock(&all_mddevs_lock);
4791         if (list_empty(&mddev->all_mddevs)) {
4792                 spin_unlock(&all_mddevs_lock);
4793                 return -EBUSY;
4794         }
4795         mddev_get(mddev);
4796         spin_unlock(&all_mddevs_lock);
4797         rv = mddev_lock(mddev);
4798         if (!rv) {
4799                 rv = entry->store(mddev, page, length);
4800                 mddev_unlock(mddev);
4801         }
4802         mddev_put(mddev);
4803         return rv;
4804 }
4805
4806 static void md_free(struct kobject *ko)
4807 {
4808         struct mddev *mddev = container_of(ko, struct mddev, kobj);
4809
4810         if (mddev->sysfs_state)
4811                 sysfs_put(mddev->sysfs_state);
4812
4813         if (mddev->gendisk) {
4814                 del_gendisk(mddev->gendisk);
4815                 put_disk(mddev->gendisk);
4816         }
4817         if (mddev->queue)
4818                 blk_cleanup_queue(mddev->queue);
4819
4820         kfree(mddev);
4821 }
4822
4823 static const struct sysfs_ops md_sysfs_ops = {
4824         .show   = md_attr_show,
4825         .store  = md_attr_store,
4826 };
4827 static struct kobj_type md_ktype = {
4828         .release        = md_free,
4829         .sysfs_ops      = &md_sysfs_ops,
4830         .default_attrs  = md_default_attrs,
4831 };
4832
4833 int mdp_major = 0;
4834
4835 static void mddev_delayed_delete(struct work_struct *ws)
4836 {
4837         struct mddev *mddev = container_of(ws, struct mddev, del_work);
4838
4839         sysfs_remove_group(&mddev->kobj, &md_bitmap_group);
4840         kobject_del(&mddev->kobj);
4841         kobject_put(&mddev->kobj);
4842 }
4843
4844 static int md_alloc(dev_t dev, char *name)
4845 {
4846         static DEFINE_MUTEX(disks_mutex);
4847         struct mddev *mddev = mddev_find(dev);
4848         struct gendisk *disk;
4849         int partitioned;
4850         int shift;
4851         int unit;
4852         int error;
4853
4854         if (!mddev)
4855                 return -ENODEV;
4856
4857         partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
4858         shift = partitioned ? MdpMinorShift : 0;
4859         unit = MINOR(mddev->unit) >> shift;
4860
4861         /* wait for any previous instance of this device to be
4862          * completely removed (mddev_delayed_delete).
4863          */
4864         flush_workqueue(md_misc_wq);
4865
4866         mutex_lock(&disks_mutex);
4867         error = -EEXIST;
4868         if (mddev->gendisk)
4869                 goto abort;
4870
4871         if (name) {
4872                 /* Need to ensure that 'name' is not a duplicate.
4873                  */
4874                 struct mddev *mddev2;
4875                 spin_lock(&all_mddevs_lock);
4876
4877                 list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
4878                         if (mddev2->gendisk &&
4879                             strcmp(mddev2->gendisk->disk_name, name) == 0) {
4880                                 spin_unlock(&all_mddevs_lock);
4881                                 goto abort;
4882                         }
4883                 spin_unlock(&all_mddevs_lock);
4884         }
4885
4886         error = -ENOMEM;
4887         mddev->queue = blk_alloc_queue(GFP_KERNEL);
4888         if (!mddev->queue)
4889                 goto abort;
4890         mddev->queue->queuedata = mddev;
4891
4892         blk_queue_make_request(mddev->queue, md_make_request);
4893         blk_set_stacking_limits(&mddev->queue->limits);
4894
4895         disk = alloc_disk(1 << shift);
4896         if (!disk) {
4897                 blk_cleanup_queue(mddev->queue);
4898                 mddev->queue = NULL;
4899                 goto abort;
4900         }
4901         disk->major = MAJOR(mddev->unit);
4902         disk->first_minor = unit << shift;
4903         if (name)
4904                 strcpy(disk->disk_name, name);
4905         else if (partitioned)
4906                 sprintf(disk->disk_name, "md_d%d", unit);
4907         else
4908                 sprintf(disk->disk_name, "md%d", unit);
4909         disk->fops = &md_fops;
4910         disk->private_data = mddev;
4911         disk->queue = mddev->queue;
4912         blk_queue_flush(mddev->queue, REQ_FLUSH | REQ_FUA);
4913         /* Allow extended partitions.  This makes the
4914          * 'mdp' device redundant, but we can't really
4915          * remove it now.
4916          */
4917         disk->flags |= GENHD_FL_EXT_DEVT;
4918         mddev->gendisk = disk;
4919         /* As soon as we call add_disk(), another thread could get
4920          * through to md_open, so make sure it doesn't get too far
4921          */
4922         mutex_lock(&mddev->open_mutex);
4923         add_disk(disk);
4924
4925         error = kobject_init_and_add(&mddev->kobj, &md_ktype,
4926                                      &disk_to_dev(disk)->kobj, "%s", "md");
4927         if (error) {
4928                 /* This isn't possible, but as kobject_init_and_add is marked
4929                  * __must_check, we must do something with the result
4930                  */
4931                 printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
4932                        disk->disk_name);
4933                 error = 0;
4934         }
4935         if (mddev->kobj.sd &&
4936             sysfs_create_group(&mddev->kobj, &md_bitmap_group))
4937                 printk(KERN_DEBUG "pointless warning\n");
4938         mutex_unlock(&mddev->open_mutex);
4939  abort:
4940         mutex_unlock(&disks_mutex);
4941         if (!error && mddev->kobj.sd) {
4942                 kobject_uevent(&mddev->kobj, KOBJ_ADD);
4943                 mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
4944         }
4945         mddev_put(mddev);
4946         return error;
4947 }
4948
4949 static struct kobject *md_probe(dev_t dev, int *part, void *data)
4950 {
4951         md_alloc(dev, NULL);
4952         return NULL;
4953 }
4954
4955 static int add_named_array(const char *val, struct kernel_param *kp)
4956 {
4957         /* val must be "md_*" where * is not all digits.
4958          * We allocate an array with a large free minor number, and
4959          * set the name to val.  val must not already be an active name.
4960          */
4961         int len = strlen(val);
4962         char buf[DISK_NAME_LEN];
4963
4964         while (len && val[len-1] == '\n')
4965                 len--;
4966         if (len >= DISK_NAME_LEN)
4967                 return -E2BIG;
4968         strlcpy(buf, val, len+1);
4969         if (strncmp(buf, "md_", 3) != 0)
4970                 return -EINVAL;
4971         return md_alloc(0, buf);
4972 }
4973
4974 static void md_safemode_timeout(unsigned long data)
4975 {
4976         struct mddev *mddev = (struct mddev *) data;
4977
4978         if (!atomic_read(&mddev->writes_pending)) {
4979                 mddev->safemode = 1;
4980                 if (mddev->external)
4981                         sysfs_notify_dirent_safe(mddev->sysfs_state);
4982         }
4983         md_wakeup_thread(mddev->thread);
4984 }
4985
4986 static int start_dirty_degraded;
4987
4988 int md_run(struct mddev *mddev)
4989 {
4990         int err;
4991         struct md_rdev *rdev;
4992         struct md_personality *pers;
4993
4994         if (list_empty(&mddev->disks))
4995                 /* cannot run an array with no devices.. */
4996                 return -EINVAL;
4997
4998         if (mddev->pers)
4999                 return -EBUSY;
5000         /* Cannot run until previous stop completes properly */
5001         if (mddev->sysfs_active)
5002                 return -EBUSY;
5003
5004         /*
5005          * Analyze all RAID superblock(s)
5006          */
5007         if (!mddev->raid_disks) {
5008                 if (!mddev->persistent)
5009                         return -EINVAL;
5010                 analyze_sbs(mddev);
5011         }
5012
5013         if (mddev->level != LEVEL_NONE)
5014                 request_module("md-level-%d", mddev->level);
5015         else if (mddev->clevel[0])
5016                 request_module("md-%s", mddev->clevel);
5017
5018         /*
5019          * Drop all container device buffers, from now on
5020          * the only valid external interface is through the md
5021          * device.
5022          */
5023         rdev_for_each(rdev, mddev) {
5024                 if (test_bit(Faulty, &rdev->flags))
5025                         continue;
5026                 sync_blockdev(rdev->bdev);
5027                 invalidate_bdev(rdev->bdev);
5028
5029                 /* perform some consistency tests on the device.
5030                  * We don't want the data to overlap the metadata,
5031                  * Internal Bitmap issues have been handled elsewhere.
5032                  */
5033                 if (rdev->meta_bdev) {
5034                         /* Nothing to check */;
5035                 } else if (rdev->data_offset < rdev->sb_start) {
5036                         if (mddev->dev_sectors &&
5037                             rdev->data_offset + mddev->dev_sectors
5038                             > rdev->sb_start) {
5039                                 printk("md: %s: data overlaps metadata\n",
5040                                        mdname(mddev));
5041                                 return -EINVAL;
5042                         }
5043                 } else {
5044                         if (rdev->sb_start + rdev->sb_size/512
5045                             > rdev->data_offset) {
5046                                 printk("md: %s: metadata overlaps data\n",
5047                                        mdname(mddev));
5048                                 return -EINVAL;
5049                         }
5050                 }
5051                 sysfs_notify_dirent_safe(rdev->sysfs_state);
5052         }
5053
5054         if (mddev->bio_set == NULL)
5055                 mddev->bio_set = bioset_create(BIO_POOL_SIZE,
5056                                                sizeof(struct mddev *));
5057
5058         spin_lock(&pers_lock);
5059         pers = find_pers(mddev->level, mddev->clevel);
5060         if (!pers || !try_module_get(pers->owner)) {
5061                 spin_unlock(&pers_lock);
5062                 if (mddev->level != LEVEL_NONE)
5063                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
5064                                mddev->level);
5065                 else
5066                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
5067                                mddev->clevel);
5068                 return -EINVAL;
5069         }
5070         mddev->pers = pers;
5071         spin_unlock(&pers_lock);
5072         if (mddev->level != pers->level) {
5073                 mddev->level = pers->level;
5074                 mddev->new_level = pers->level;
5075         }
5076         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
5077
5078         if (mddev->reshape_position != MaxSector &&
5079             pers->start_reshape == NULL) {
5080                 /* This personality cannot handle reshaping... */
5081                 mddev->pers = NULL;
5082                 module_put(pers->owner);
5083                 return -EINVAL;
5084         }
5085
5086         if (pers->sync_request) {
5087                 /* Warn if this is a potentially silly
5088                  * configuration.
5089                  */
5090                 char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
5091                 struct md_rdev *rdev2;
5092                 int warned = 0;
5093
5094                 rdev_for_each(rdev, mddev)
5095                         rdev_for_each(rdev2, mddev) {
5096                                 if (rdev < rdev2 &&
5097                                     rdev->bdev->bd_contains ==
5098                                     rdev2->bdev->bd_contains) {
5099                                         printk(KERN_WARNING
5100                                                "%s: WARNING: %s appears to be"
5101                                                " on the same physical disk as"
5102                                                " %s.\n",
5103                                                mdname(mddev),
5104                                                bdevname(rdev->bdev,b),
5105                                                bdevname(rdev2->bdev,b2));
5106                                         warned = 1;
5107                                 }
5108                         }
5109
5110                 if (warned)
5111                         printk(KERN_WARNING
5112                                "True protection against single-disk"
5113                                " failure might be compromised.\n");
5114         }
5115
5116         mddev->recovery = 0;
5117         /* may be over-ridden by personality */
5118         mddev->resync_max_sectors = mddev->dev_sectors;
5119
5120         mddev->ok_start_degraded = start_dirty_degraded;
5121
5122         if (start_readonly && mddev->ro == 0)
5123                 mddev->ro = 2; /* read-only, but switch on first write */
5124
5125         err = mddev->pers->run(mddev);
5126         if (err)
5127                 printk(KERN_ERR "md: pers->run() failed ...\n");
5128         else if (mddev->pers->size(mddev, 0, 0) < mddev->array_sectors) {
5129                 WARN_ONCE(!mddev->external_size, "%s: default size too small,"
5130                           " but 'external_size' not in effect?\n", __func__);
5131                 printk(KERN_ERR
5132                        "md: invalid array_size %llu > default size %llu\n",
5133                        (unsigned long long)mddev->array_sectors / 2,
5134                        (unsigned long long)mddev->pers->size(mddev, 0, 0) / 2);
5135                 err = -EINVAL;
5136                 mddev->pers->stop(mddev);
5137         }
5138         if (err == 0 && mddev->pers->sync_request &&
5139             (mddev->bitmap_info.file || mddev->bitmap_info.offset)) {
5140                 err = bitmap_create(mddev);
5141                 if (err) {
5142                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
5143                                mdname(mddev), err);
5144                         mddev->pers->stop(mddev);
5145                 }
5146         }
5147         if (err) {
5148                 module_put(mddev->pers->owner);
5149                 mddev->pers = NULL;
5150                 bitmap_destroy(mddev);
5151                 return err;
5152         }
5153         if (mddev->pers->sync_request) {
5154                 if (mddev->kobj.sd &&
5155                     sysfs_create_group(&mddev->kobj, &md_redundancy_group))
5156                         printk(KERN_WARNING
5157                                "md: cannot register extra attributes for %s\n",
5158                                mdname(mddev));
5159                 mddev->sysfs_action = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_action");
5160         } else if (mddev->ro == 2) /* auto-readonly not meaningful */
5161                 mddev->ro = 0;
5162
5163         atomic_set(&mddev->writes_pending,0);
5164         atomic_set(&mddev->max_corr_read_errors,
5165                    MD_DEFAULT_MAX_CORRECTED_READ_ERRORS);
5166         mddev->safemode = 0;
5167         mddev->safemode_timer.function = md_safemode_timeout;
5168         mddev->safemode_timer.data = (unsigned long) mddev;
5169         mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
5170         mddev->in_sync = 1;
5171         smp_wmb();
5172         mddev->ready = 1;
5173         rdev_for_each(rdev, mddev)
5174                 if (rdev->raid_disk >= 0)
5175                         if (sysfs_link_rdev(mddev, rdev))
5176                                 /* failure here is OK */;
5177
5178         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5179
5180         if (mddev->flags)
5181                 md_update_sb(mddev, 0);
5182
5183         md_new_event(mddev);
5184         sysfs_notify_dirent_safe(mddev->sysfs_state);
5185         sysfs_notify_dirent_safe(mddev->sysfs_action);
5186         sysfs_notify(&mddev->kobj, NULL, "degraded");
5187         return 0;
5188 }
5189 EXPORT_SYMBOL_GPL(md_run);
5190
5191 static int do_md_run(struct mddev *mddev)
5192 {
5193         int err;
5194
5195         err = md_run(mddev);
5196         if (err)
5197                 goto out;
5198         err = bitmap_load(mddev);
5199         if (err) {
5200                 bitmap_destroy(mddev);
5201                 goto out;
5202         }
5203
5204         md_wakeup_thread(mddev->thread);
5205         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
5206
5207         set_capacity(mddev->gendisk, mddev->array_sectors);
5208         revalidate_disk(mddev->gendisk);
5209         mddev->changed = 1;
5210         kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
5211 out:
5212         return err;
5213 }
5214
5215 static int restart_array(struct mddev *mddev)
5216 {
5217         struct gendisk *disk = mddev->gendisk;
5218
5219         /* Complain if it has no devices */
5220         if (list_empty(&mddev->disks))
5221                 return -ENXIO;
5222         if (!mddev->pers)
5223                 return -EINVAL;
5224         if (!mddev->ro)
5225                 return -EBUSY;
5226         mddev->safemode = 0;
5227         mddev->ro = 0;
5228         set_disk_ro(disk, 0);
5229         printk(KERN_INFO "md: %s switched to read-write mode.\n",
5230                 mdname(mddev));
5231         /* Kick recovery or resync if necessary */
5232         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5233         md_wakeup_thread(mddev->thread);
5234         md_wakeup_thread(mddev->sync_thread);
5235         sysfs_notify_dirent_safe(mddev->sysfs_state);
5236         return 0;
5237 }
5238
5239 /* similar to deny_write_access, but accounts for our holding a reference
5240  * to the file ourselves */
5241 static int deny_bitmap_write_access(struct file * file)
5242 {
5243         struct inode *inode = file->f_mapping->host;
5244
5245         spin_lock(&inode->i_lock);
5246         if (atomic_read(&inode->i_writecount) > 1) {
5247                 spin_unlock(&inode->i_lock);
5248                 return -ETXTBSY;
5249         }
5250         atomic_set(&inode->i_writecount, -1);
5251         spin_unlock(&inode->i_lock);
5252
5253         return 0;
5254 }
5255
5256 void restore_bitmap_write_access(struct file *file)
5257 {
5258         struct inode *inode = file->f_mapping->host;
5259
5260         spin_lock(&inode->i_lock);
5261         atomic_set(&inode->i_writecount, 1);
5262         spin_unlock(&inode->i_lock);
5263 }
5264
5265 static void md_clean(struct mddev *mddev)
5266 {
5267         mddev->array_sectors = 0;
5268         mddev->external_size = 0;
5269         mddev->dev_sectors = 0;
5270         mddev->raid_disks = 0;
5271         mddev->recovery_cp = 0;
5272         mddev->resync_min = 0;
5273         mddev->resync_max = MaxSector;
5274         mddev->reshape_position = MaxSector;
5275         mddev->external = 0;
5276         mddev->persistent = 0;
5277         mddev->level = LEVEL_NONE;
5278         mddev->clevel[0] = 0;
5279         mddev->flags = 0;
5280         mddev->ro = 0;
5281         mddev->metadata_type[0] = 0;
5282         mddev->chunk_sectors = 0;
5283         mddev->ctime = mddev->utime = 0;
5284         mddev->layout = 0;
5285         mddev->max_disks = 0;
5286         mddev->events = 0;
5287         mddev->can_decrease_events = 0;
5288         mddev->delta_disks = 0;
5289         mddev->reshape_backwards = 0;
5290         mddev->new_level = LEVEL_NONE;
5291         mddev->new_layout = 0;
5292         mddev->new_chunk_sectors = 0;
5293         mddev->curr_resync = 0;
5294         mddev->resync_mismatches = 0;
5295         mddev->suspend_lo = mddev->suspend_hi = 0;
5296         mddev->sync_speed_min = mddev->sync_speed_max = 0;
5297         mddev->recovery = 0;
5298         mddev->in_sync = 0;
5299         mddev->changed = 0;
5300         mddev->degraded = 0;
5301         mddev->safemode = 0;
5302         mddev->merge_check_needed = 0;
5303         mddev->bitmap_info.offset = 0;
5304         mddev->bitmap_info.default_offset = 0;
5305         mddev->bitmap_info.default_space = 0;
5306         mddev->bitmap_info.chunksize = 0;
5307         mddev->bitmap_info.daemon_sleep = 0;
5308         mddev->bitmap_info.max_write_behind = 0;
5309 }
5310
5311 static void __md_stop_writes(struct mddev *mddev)
5312 {
5313         if (mddev->sync_thread) {
5314                 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5315                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5316                 reap_sync_thread(mddev);
5317         }
5318
5319         del_timer_sync(&mddev->safemode_timer);
5320
5321         bitmap_flush(mddev);
5322         md_super_wait(mddev);
5323
5324         if (!mddev->in_sync || mddev->flags) {
5325                 /* mark array as shutdown cleanly */
5326                 mddev->in_sync = 1;
5327                 md_update_sb(mddev, 1);
5328         }
5329 }
5330
5331 void md_stop_writes(struct mddev *mddev)
5332 {
5333         mddev_lock(mddev);
5334         __md_stop_writes(mddev);
5335         mddev_unlock(mddev);
5336 }
5337 EXPORT_SYMBOL_GPL(md_stop_writes);
5338
5339 void md_stop(struct mddev *mddev)
5340 {
5341         mddev->ready = 0;
5342         mddev->pers->stop(mddev);
5343         if (mddev->pers->sync_request && mddev->to_remove == NULL)
5344                 mddev->to_remove = &md_redundancy_group;
5345         module_put(mddev->pers->owner);
5346         mddev->pers = NULL;
5347         clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5348 }
5349 EXPORT_SYMBOL_GPL(md_stop);
5350
5351 static int md_set_readonly(struct mddev *mddev, struct block_device *bdev)
5352 {
5353         int err = 0;
5354         mutex_lock(&mddev->open_mutex);
5355         if (atomic_read(&mddev->openers) > !!bdev) {
5356                 printk("md: %s still in use.\n",mdname(mddev));
5357                 err = -EBUSY;
5358                 goto out;
5359         }
5360         if (bdev)
5361                 sync_blockdev(bdev);
5362         if (mddev->pers) {
5363                 __md_stop_writes(mddev);
5364
5365                 err  = -ENXIO;
5366                 if (mddev->ro==1)
5367                         goto out;
5368                 mddev->ro = 1;
5369                 set_disk_ro(mddev->gendisk, 1);
5370                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5371                 sysfs_notify_dirent_safe(mddev->sysfs_state);
5372                 err = 0;
5373         }
5374 out:
5375         mutex_unlock(&mddev->open_mutex);
5376         return err;
5377 }
5378
5379 /* mode:
5380  *   0 - completely stop and dis-assemble array
5381  *   2 - stop but do not disassemble array
5382  */
5383 static int do_md_stop(struct mddev * mddev, int mode,
5384                       struct block_device *bdev)
5385 {
5386         struct gendisk *disk = mddev->gendisk;
5387         struct md_rdev *rdev;
5388
5389         mutex_lock(&mddev->open_mutex);
5390         if (atomic_read(&mddev->openers) > !!bdev ||
5391             mddev->sysfs_active) {
5392                 printk("md: %s still in use.\n",mdname(mddev));
5393                 mutex_unlock(&mddev->open_mutex);
5394                 return -EBUSY;
5395         }
5396         if (bdev)
5397                 /* It is possible IO was issued on some other
5398                  * open file which was closed before we took ->open_mutex.
5399                  * As that was not the last close __blkdev_put will not
5400                  * have called sync_blockdev, so we must.
5401                  */
5402                 sync_blockdev(bdev);
5403
5404         if (mddev->pers) {
5405                 if (mddev->ro)
5406                         set_disk_ro(disk, 0);
5407
5408                 __md_stop_writes(mddev);
5409                 md_stop(mddev);
5410                 mddev->queue->merge_bvec_fn = NULL;
5411                 mddev->queue->backing_dev_info.congested_fn = NULL;
5412
5413                 /* tell userspace to handle 'inactive' */
5414                 sysfs_notify_dirent_safe(mddev->sysfs_state);
5415
5416                 rdev_for_each(rdev, mddev)
5417                         if (rdev->raid_disk >= 0)
5418                                 sysfs_unlink_rdev(mddev, rdev);
5419
5420                 set_capacity(disk, 0);
5421                 mutex_unlock(&mddev->open_mutex);
5422                 mddev->changed = 1;
5423                 revalidate_disk(disk);
5424
5425                 if (mddev->ro)
5426                         mddev->ro = 0;
5427         } else
5428                 mutex_unlock(&mddev->open_mutex);
5429         /*
5430          * Free resources if final stop
5431          */
5432         if (mode == 0) {
5433                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
5434
5435                 bitmap_destroy(mddev);
5436                 if (mddev->bitmap_info.file) {
5437                         restore_bitmap_write_access(mddev->bitmap_info.file);
5438                         fput(mddev->bitmap_info.file);
5439                         mddev->bitmap_info.file = NULL;
5440                 }
5441                 mddev->bitmap_info.offset = 0;
5442
5443                 export_array(mddev);
5444
5445                 md_clean(mddev);
5446                 kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
5447                 if (mddev->hold_active == UNTIL_STOP)
5448                         mddev->hold_active = 0;
5449         }
5450         blk_integrity_unregister(disk);
5451         md_new_event(mddev);
5452         sysfs_notify_dirent_safe(mddev->sysfs_state);
5453         return 0;
5454 }
5455
5456 #ifndef MODULE
5457 static void autorun_array(struct mddev *mddev)
5458 {
5459         struct md_rdev *rdev;
5460         int err;
5461
5462         if (list_empty(&mddev->disks))
5463                 return;
5464
5465         printk(KERN_INFO "md: running: ");
5466
5467         rdev_for_each(rdev, mddev) {
5468                 char b[BDEVNAME_SIZE];
5469                 printk("<%s>", bdevname(rdev->bdev,b));
5470         }
5471         printk("\n");
5472
5473         err = do_md_run(mddev);
5474         if (err) {
5475                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
5476                 do_md_stop(mddev, 0, NULL);
5477         }
5478 }
5479
5480 /*
5481  * lets try to run arrays based on all disks that have arrived
5482  * until now. (those are in pending_raid_disks)
5483  *
5484  * the method: pick the first pending disk, collect all disks with
5485  * the same UUID, remove all from the pending list and put them into
5486  * the 'same_array' list. Then order this list based on superblock
5487  * update time (freshest comes first), kick out 'old' disks and
5488  * compare superblocks. If everything's fine then run it.
5489  *
5490  * If "unit" is allocated, then bump its reference count
5491  */
5492 static void autorun_devices(int part)
5493 {
5494         struct md_rdev *rdev0, *rdev, *tmp;
5495         struct mddev *mddev;
5496         char b[BDEVNAME_SIZE];
5497
5498         printk(KERN_INFO "md: autorun ...\n");
5499         while (!list_empty(&pending_raid_disks)) {
5500                 int unit;
5501                 dev_t dev;
5502                 LIST_HEAD(candidates);
5503                 rdev0 = list_entry(pending_raid_disks.next,
5504                                          struct md_rdev, same_set);
5505
5506                 printk(KERN_INFO "md: considering %s ...\n",
5507                         bdevname(rdev0->bdev,b));
5508                 INIT_LIST_HEAD(&candidates);
5509                 rdev_for_each_list(rdev, tmp, &pending_raid_disks)
5510                         if (super_90_load(rdev, rdev0, 0) >= 0) {
5511                                 printk(KERN_INFO "md:  adding %s ...\n",
5512                                         bdevname(rdev->bdev,b));
5513                                 list_move(&rdev->same_set, &candidates);
5514                         }
5515                 /*
5516                  * now we have a set of devices, with all of them having
5517                  * mostly sane superblocks. It's time to allocate the
5518                  * mddev.
5519                  */
5520                 if (part) {
5521                         dev = MKDEV(mdp_major,
5522                                     rdev0->preferred_minor << MdpMinorShift);
5523                         unit = MINOR(dev) >> MdpMinorShift;
5524                 } else {
5525                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
5526                         unit = MINOR(dev);
5527                 }
5528                 if (rdev0->preferred_minor != unit) {
5529                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
5530                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
5531                         break;
5532                 }
5533
5534                 md_probe(dev, NULL, NULL);
5535                 mddev = mddev_find(dev);
5536                 if (!mddev || !mddev->gendisk) {
5537                         if (mddev)
5538                                 mddev_put(mddev);
5539                         printk(KERN_ERR
5540                                 "md: cannot allocate memory for md drive.\n");
5541                         break;
5542                 }
5543                 if (mddev_lock(mddev))
5544                         printk(KERN_WARNING "md: %s locked, cannot run\n",
5545                                mdname(mddev));
5546                 else if (mddev->raid_disks || mddev->major_version
5547                          || !list_empty(&mddev->disks)) {
5548                         printk(KERN_WARNING
5549                                 "md: %s already running, cannot run %s\n",
5550                                 mdname(mddev), bdevname(rdev0->bdev,b));
5551                         mddev_unlock(mddev);
5552                 } else {
5553                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
5554                         mddev->persistent = 1;
5555                         rdev_for_each_list(rdev, tmp, &candidates) {
5556                                 list_del_init(&rdev->same_set);
5557                                 if (bind_rdev_to_array(rdev, mddev))
5558                                         export_rdev(rdev);
5559                         }
5560                         autorun_array(mddev);
5561                         mddev_unlock(mddev);
5562                 }
5563                 /* on success, candidates will be empty, on error
5564                  * it won't...
5565                  */
5566                 rdev_for_each_list(rdev, tmp, &candidates) {
5567                         list_del_init(&rdev->same_set);
5568                         export_rdev(rdev);
5569                 }
5570                 mddev_put(mddev);
5571         }
5572         printk(KERN_INFO "md: ... autorun DONE.\n");
5573 }
5574 #endif /* !MODULE */
5575
5576 static int get_version(void __user * arg)
5577 {
5578         mdu_version_t ver;
5579
5580         ver.major = MD_MAJOR_VERSION;
5581         ver.minor = MD_MINOR_VERSION;
5582         ver.patchlevel = MD_PATCHLEVEL_VERSION;
5583
5584         if (copy_to_user(arg, &ver, sizeof(ver)))
5585                 return -EFAULT;
5586
5587         return 0;
5588 }
5589
5590 static int get_array_info(struct mddev * mddev, void __user * arg)
5591 {
5592         mdu_array_info_t info;
5593         int nr,working,insync,failed,spare;
5594         struct md_rdev *rdev;
5595
5596         nr=working=insync=failed=spare=0;
5597         rdev_for_each(rdev, mddev) {
5598                 nr++;
5599                 if (test_bit(Faulty, &rdev->flags))
5600                         failed++;
5601                 else {
5602                         working++;
5603                         if (test_bit(In_sync, &rdev->flags))
5604                                 insync++;
5605                         else
5606                                 spare++;
5607                 }
5608         }
5609
5610         info.major_version = mddev->major_version;
5611         info.minor_version = mddev->minor_version;
5612         info.patch_version = MD_PATCHLEVEL_VERSION;
5613         info.ctime         = mddev->ctime;
5614         info.level         = mddev->level;
5615         info.size          = mddev->dev_sectors / 2;
5616         if (info.size != mddev->dev_sectors / 2) /* overflow */
5617                 info.size = -1;
5618         info.nr_disks      = nr;
5619         info.raid_disks    = mddev->raid_disks;
5620         info.md_minor      = mddev->md_minor;
5621         info.not_persistent= !mddev->persistent;
5622
5623         info.utime         = mddev->utime;
5624         info.state         = 0;
5625         if (mddev->in_sync)
5626                 info.state = (1<<MD_SB_CLEAN);
5627         if (mddev->bitmap && mddev->bitmap_info.offset)
5628                 info.state = (1<<MD_SB_BITMAP_PRESENT);
5629         info.active_disks  = insync;
5630         info.working_disks = working;
5631         info.failed_disks  = failed;
5632         info.spare_disks   = spare;
5633
5634         info.layout        = mddev->layout;
5635         info.chunk_size    = mddev->chunk_sectors << 9;
5636
5637         if (copy_to_user(arg, &info, sizeof(info)))
5638                 return -EFAULT;
5639
5640         return 0;
5641 }
5642
5643 static int get_bitmap_file(struct mddev * mddev, void __user * arg)
5644 {
5645         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
5646         char *ptr, *buf = NULL;
5647         int err = -ENOMEM;
5648
5649         if (md_allow_write(mddev))
5650                 file = kmalloc(sizeof(*file), GFP_NOIO);
5651         else
5652                 file = kmalloc(sizeof(*file), GFP_KERNEL);
5653
5654         if (!file)
5655                 goto out;
5656
5657         /* bitmap disabled, zero the first byte and copy out */
5658         if (!mddev->bitmap || !mddev->bitmap->storage.file) {
5659                 file->pathname[0] = '\0';
5660                 goto copy_out;
5661         }
5662
5663         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
5664         if (!buf)
5665                 goto out;
5666
5667         ptr = d_path(&mddev->bitmap->storage.file->f_path,
5668                      buf, sizeof(file->pathname));
5669         if (IS_ERR(ptr))
5670                 goto out;
5671
5672         strcpy(file->pathname, ptr);
5673
5674 copy_out:
5675         err = 0;
5676         if (copy_to_user(arg, file, sizeof(*file)))
5677                 err = -EFAULT;
5678 out:
5679         kfree(buf);
5680         kfree(file);
5681         return err;
5682 }
5683
5684 static int get_disk_info(struct mddev * mddev, void __user * arg)
5685 {
5686         mdu_disk_info_t info;
5687         struct md_rdev *rdev;
5688
5689         if (copy_from_user(&info, arg, sizeof(info)))
5690                 return -EFAULT;
5691
5692         rdev = find_rdev_nr(mddev, info.number);
5693         if (rdev) {
5694                 info.major = MAJOR(rdev->bdev->bd_dev);
5695                 info.minor = MINOR(rdev->bdev->bd_dev);
5696                 info.raid_disk = rdev->raid_disk;
5697                 info.state = 0;
5698                 if (test_bit(Faulty, &rdev->flags))
5699                         info.state |= (1<<MD_DISK_FAULTY);
5700                 else if (test_bit(In_sync, &rdev->flags)) {
5701                         info.state |= (1<<MD_DISK_ACTIVE);
5702                         info.state |= (1<<MD_DISK_SYNC);
5703                 }
5704                 if (test_bit(WriteMostly, &rdev->flags))
5705                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
5706         } else {
5707                 info.major = info.minor = 0;
5708                 info.raid_disk = -1;
5709                 info.state = (1<<MD_DISK_REMOVED);
5710         }
5711
5712         if (copy_to_user(arg, &info, sizeof(info)))
5713                 return -EFAULT;
5714
5715         return 0;
5716 }
5717
5718 static int add_new_disk(struct mddev * mddev, mdu_disk_info_t *info)
5719 {
5720         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
5721         struct md_rdev *rdev;
5722         dev_t dev = MKDEV(info->major,info->minor);
5723
5724         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
5725                 return -EOVERFLOW;
5726
5727         if (!mddev->raid_disks) {
5728                 int err;
5729                 /* expecting a device which has a superblock */
5730                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
5731                 if (IS_ERR(rdev)) {
5732                         printk(KERN_WARNING
5733                                 "md: md_import_device returned %ld\n",
5734                                 PTR_ERR(rdev));
5735                         return PTR_ERR(rdev);
5736                 }
5737                 if (!list_empty(&mddev->disks)) {
5738                         struct md_rdev *rdev0
5739                                 = list_entry(mddev->disks.next,
5740                                              struct md_rdev, same_set);
5741                         err = super_types[mddev->major_version]
5742                                 .load_super(rdev, rdev0, mddev->minor_version);
5743                         if (err < 0) {
5744                                 printk(KERN_WARNING
5745                                         "md: %s has different UUID to %s\n",
5746                                         bdevname(rdev->bdev,b),
5747                                         bdevname(rdev0->bdev,b2));
5748                                 export_rdev(rdev);
5749                                 return -EINVAL;
5750                         }
5751                 }
5752                 err = bind_rdev_to_array(rdev, mddev);
5753                 if (err)
5754                         export_rdev(rdev);
5755                 return err;
5756         }
5757
5758         /*
5759          * add_new_disk can be used once the array is assembled
5760          * to add "hot spares".  They must already have a superblock
5761          * written
5762          */
5763         if (mddev->pers) {
5764                 int err;
5765                 if (!mddev->pers->hot_add_disk) {
5766                         printk(KERN_WARNING
5767                                 "%s: personality does not support diskops!\n",
5768                                mdname(mddev));
5769                         return -EINVAL;
5770                 }
5771                 if (mddev->persistent)
5772                         rdev = md_import_device(dev, mddev->major_version,
5773                                                 mddev->minor_version);
5774                 else
5775                         rdev = md_import_device(dev, -1, -1);
5776                 if (IS_ERR(rdev)) {
5777                         printk(KERN_WARNING
5778                                 "md: md_import_device returned %ld\n",
5779                                 PTR_ERR(rdev));
5780                         return PTR_ERR(rdev);
5781                 }
5782                 /* set saved_raid_disk if appropriate */
5783                 if (!mddev->persistent) {
5784                         if (info->state & (1<<MD_DISK_SYNC)  &&
5785                             info->raid_disk < mddev->raid_disks) {
5786                                 rdev->raid_disk = info->raid_disk;
5787                                 set_bit(In_sync, &rdev->flags);
5788                         } else
5789                                 rdev->raid_disk = -1;
5790                 } else
5791                         super_types[mddev->major_version].
5792                                 validate_super(mddev, rdev);
5793                 if ((info->state & (1<<MD_DISK_SYNC)) &&
5794                      rdev->raid_disk != info->raid_disk) {
5795                         /* This was a hot-add request, but events doesn't
5796                          * match, so reject it.
5797                          */
5798                         export_rdev(rdev);
5799                         return -EINVAL;
5800                 }
5801
5802                 if (test_bit(In_sync, &rdev->flags))
5803                         rdev->saved_raid_disk = rdev->raid_disk;
5804                 else
5805                         rdev->saved_raid_disk = -1;
5806
5807                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
5808                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
5809                         set_bit(WriteMostly, &rdev->flags);
5810                 else
5811                         clear_bit(WriteMostly, &rdev->flags);
5812
5813                 rdev->raid_disk = -1;
5814                 err = bind_rdev_to_array(rdev, mddev);
5815                 if (!err && !mddev->pers->hot_remove_disk) {
5816                         /* If there is hot_add_disk but no hot_remove_disk
5817                          * then added disks for geometry changes,
5818                          * and should be added immediately.
5819                          */
5820                         super_types[mddev->major_version].
5821                                 validate_super(mddev, rdev);
5822                         err = mddev->pers->hot_add_disk(mddev, rdev);
5823                         if (err)
5824                                 unbind_rdev_from_array(rdev);
5825                 }
5826                 if (err)
5827                         export_rdev(rdev);
5828                 else
5829                         sysfs_notify_dirent_safe(rdev->sysfs_state);
5830
5831                 md_update_sb(mddev, 1);
5832                 if (mddev->degraded)
5833                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
5834                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5835                 if (!err)
5836                         md_new_event(mddev);
5837                 md_wakeup_thread(mddev->thread);
5838                 return err;
5839         }
5840
5841         /* otherwise, add_new_disk is only allowed
5842          * for major_version==0 superblocks
5843          */
5844         if (mddev->major_version != 0) {
5845                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
5846                        mdname(mddev));
5847                 return -EINVAL;
5848         }
5849
5850         if (!(info->state & (1<<MD_DISK_FAULTY))) {
5851                 int err;
5852                 rdev = md_import_device(dev, -1, 0);
5853                 if (IS_ERR(rdev)) {
5854                         printk(KERN_WARNING
5855                                 "md: error, md_import_device() returned %ld\n",
5856                                 PTR_ERR(rdev));
5857                         return PTR_ERR(rdev);
5858                 }
5859                 rdev->desc_nr = info->number;
5860                 if (info->raid_disk < mddev->raid_disks)
5861                         rdev->raid_disk = info->raid_disk;
5862                 else
5863                         rdev->raid_disk = -1;
5864
5865                 if (rdev->raid_disk < mddev->raid_disks)
5866                         if (info->state & (1<<MD_DISK_SYNC))
5867                                 set_bit(In_sync, &rdev->flags);
5868
5869                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
5870                         set_bit(WriteMostly, &rdev->flags);
5871
5872                 if (!mddev->persistent) {
5873                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
5874                         rdev->sb_start = i_size_read(rdev->bdev->bd_inode) / 512;
5875                 } else
5876                         rdev->sb_start = calc_dev_sboffset(rdev);
5877                 rdev->sectors = rdev->sb_start;
5878
5879                 err = bind_rdev_to_array(rdev, mddev);
5880                 if (err) {
5881                         export_rdev(rdev);
5882                         return err;
5883                 }
5884         }
5885
5886         return 0;
5887 }
5888
5889 static int hot_remove_disk(struct mddev * mddev, dev_t dev)
5890 {
5891         char b[BDEVNAME_SIZE];
5892         struct md_rdev *rdev;
5893
5894         rdev = find_rdev(mddev, dev);
5895         if (!rdev)
5896                 return -ENXIO;
5897
5898         if (rdev->raid_disk >= 0)
5899                 goto busy;
5900
5901         kick_rdev_from_array(rdev);
5902         md_update_sb(mddev, 1);
5903         md_new_event(mddev);
5904
5905         return 0;
5906 busy:
5907         printk(KERN_WARNING "md: cannot remove active disk %s from %s ...\n",
5908                 bdevname(rdev->bdev,b), mdname(mddev));
5909         return -EBUSY;
5910 }
5911
5912 static int hot_add_disk(struct mddev * mddev, dev_t dev)
5913 {
5914         char b[BDEVNAME_SIZE];
5915         int err;
5916         struct md_rdev *rdev;
5917
5918         if (!mddev->pers)
5919                 return -ENODEV;
5920
5921         if (mddev->major_version != 0) {
5922                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
5923                         " version-0 superblocks.\n",
5924                         mdname(mddev));
5925                 return -EINVAL;
5926         }
5927         if (!mddev->pers->hot_add_disk) {
5928                 printk(KERN_WARNING
5929                         "%s: personality does not support diskops!\n",
5930                         mdname(mddev));
5931                 return -EINVAL;
5932         }
5933
5934         rdev = md_import_device(dev, -1, 0);
5935         if (IS_ERR(rdev)) {
5936                 printk(KERN_WARNING
5937                         "md: error, md_import_device() returned %ld\n",
5938                         PTR_ERR(rdev));
5939                 return -EINVAL;
5940         }
5941
5942         if (mddev->persistent)
5943                 rdev->sb_start = calc_dev_sboffset(rdev);
5944         else
5945                 rdev->sb_start = i_size_read(rdev->bdev->bd_inode) / 512;
5946
5947         rdev->sectors = rdev->sb_start;
5948
5949         if (test_bit(Faulty, &rdev->flags)) {
5950                 printk(KERN_WARNING
5951                         "md: can not hot-add faulty %s disk to %s!\n",
5952                         bdevname(rdev->bdev,b), mdname(mddev));
5953                 err = -EINVAL;
5954                 goto abort_export;
5955         }
5956         clear_bit(In_sync, &rdev->flags);
5957         rdev->desc_nr = -1;
5958         rdev->saved_raid_disk = -1;
5959         err = bind_rdev_to_array(rdev, mddev);
5960         if (err)
5961                 goto abort_export;
5962
5963         /*
5964          * The rest should better be atomic, we can have disk failures
5965          * noticed in interrupt contexts ...
5966          */
5967
5968         rdev->raid_disk = -1;
5969
5970         md_update_sb(mddev, 1);
5971
5972         /*
5973          * Kick recovery, maybe this spare has to be added to the
5974          * array immediately.
5975          */
5976         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5977         md_wakeup_thread(mddev->thread);
5978         md_new_event(mddev);
5979         return 0;
5980
5981 abort_export:
5982         export_rdev(rdev);
5983         return err;
5984 }
5985
5986 static int set_bitmap_file(struct mddev *mddev, int fd)
5987 {
5988         int err;
5989
5990         if (mddev->pers) {
5991                 if (!mddev->pers->quiesce)
5992                         return -EBUSY;
5993                 if (mddev->recovery || mddev->sync_thread)
5994                         return -EBUSY;
5995                 /* we should be able to change the bitmap.. */
5996         }
5997
5998
5999         if (fd >= 0) {
6000                 if (mddev->bitmap)
6001                         return -EEXIST; /* cannot add when bitmap is present */
6002                 mddev->bitmap_info.file = fget(fd);
6003
6004                 if (mddev->bitmap_info.file == NULL) {
6005                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
6006                                mdname(mddev));
6007                         return -EBADF;
6008                 }
6009
6010                 err = deny_bitmap_write_access(mddev->bitmap_info.file);
6011                 if (err) {
6012                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
6013                                mdname(mddev));
6014                         fput(mddev->bitmap_info.file);
6015                         mddev->bitmap_info.file = NULL;
6016                         return err;
6017                 }
6018                 mddev->bitmap_info.offset = 0; /* file overrides offset */
6019         } else if (mddev->bitmap == NULL)
6020                 return -ENOENT; /* cannot remove what isn't there */
6021         err = 0;
6022         if (mddev->pers) {
6023                 mddev->pers->quiesce(mddev, 1);
6024                 if (fd >= 0) {
6025                         err = bitmap_create(mddev);
6026                         if (!err)
6027                                 err = bitmap_load(mddev);
6028                 }
6029                 if (fd < 0 || err) {
6030                         bitmap_destroy(mddev);
6031                         fd = -1; /* make sure to put the file */
6032                 }
6033                 mddev->pers->quiesce(mddev, 0);
6034         }
6035         if (fd < 0) {
6036                 if (mddev->bitmap_info.file) {
6037                         restore_bitmap_write_access(mddev->bitmap_info.file);
6038                         fput(mddev->bitmap_info.file);
6039                 }
6040                 mddev->bitmap_info.file = NULL;
6041         }
6042
6043         return err;
6044 }
6045
6046 /*
6047  * set_array_info is used two different ways
6048  * The original usage is when creating a new array.
6049  * In this usage, raid_disks is > 0 and it together with
6050  *  level, size, not_persistent,layout,chunksize determine the
6051  *  shape of the array.
6052  *  This will always create an array with a type-0.90.0 superblock.
6053  * The newer usage is when assembling an array.
6054  *  In this case raid_disks will be 0, and the major_version field is
6055  *  use to determine which style super-blocks are to be found on the devices.
6056  *  The minor and patch _version numbers are also kept incase the
6057  *  super_block handler wishes to interpret them.
6058  */
6059 static int set_array_info(struct mddev * mddev, mdu_array_info_t *info)
6060 {
6061
6062         if (info->raid_disks == 0) {
6063                 /* just setting version number for superblock loading */
6064                 if (info->major_version < 0 ||
6065                     info->major_version >= ARRAY_SIZE(super_types) ||
6066                     super_types[info->major_version].name == NULL) {
6067                         /* maybe try to auto-load a module? */
6068                         printk(KERN_INFO
6069                                 "md: superblock version %d not known\n",
6070                                 info->major_version);
6071                         return -EINVAL;
6072                 }
6073                 mddev->major_version = info->major_version;
6074                 mddev->minor_version = info->minor_version;
6075                 mddev->patch_version = info->patch_version;
6076                 mddev->persistent = !info->not_persistent;
6077                 /* ensure mddev_put doesn't delete this now that there
6078                  * is some minimal configuration.
6079                  */
6080                 mddev->ctime         = get_seconds();
6081                 return 0;
6082         }
6083         mddev->major_version = MD_MAJOR_VERSION;
6084         mddev->minor_version = MD_MINOR_VERSION;
6085         mddev->patch_version = MD_PATCHLEVEL_VERSION;
6086         mddev->ctime         = get_seconds();
6087
6088         mddev->level         = info->level;
6089         mddev->clevel[0]     = 0;
6090         mddev->dev_sectors   = 2 * (sector_t)info->size;
6091         mddev->raid_disks    = info->raid_disks;
6092         /* don't set md_minor, it is determined by which /dev/md* was
6093          * openned
6094          */
6095         if (info->state & (1<<MD_SB_CLEAN))
6096                 mddev->recovery_cp = MaxSector;
6097         else
6098                 mddev->recovery_cp = 0;
6099         mddev->persistent    = ! info->not_persistent;
6100         mddev->external      = 0;
6101
6102         mddev->layout        = info->layout;
6103         mddev->chunk_sectors = info->chunk_size >> 9;
6104
6105         mddev->max_disks     = MD_SB_DISKS;
6106
6107         if (mddev->persistent)
6108                 mddev->flags         = 0;
6109         set_bit(MD_CHANGE_DEVS, &mddev->flags);
6110
6111         mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
6112         mddev->bitmap_info.default_space = 64*2 - (MD_SB_BYTES >> 9);
6113         mddev->bitmap_info.offset = 0;
6114
6115         mddev->reshape_position = MaxSector;
6116
6117         /*
6118          * Generate a 128 bit UUID
6119          */
6120         get_random_bytes(mddev->uuid, 16);
6121
6122         mddev->new_level = mddev->level;
6123         mddev->new_chunk_sectors = mddev->chunk_sectors;
6124         mddev->new_layout = mddev->layout;
6125         mddev->delta_disks = 0;
6126         mddev->reshape_backwards = 0;
6127
6128         return 0;
6129 }
6130
6131 void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors)
6132 {
6133         WARN(!mddev_is_locked(mddev), "%s: unlocked mddev!\n", __func__);
6134
6135         if (mddev->external_size)
6136                 return;
6137
6138         mddev->array_sectors = array_sectors;
6139 }
6140 EXPORT_SYMBOL(md_set_array_sectors);
6141
6142 static int update_size(struct mddev *mddev, sector_t num_sectors)
6143 {
6144         struct md_rdev *rdev;
6145         int rv;
6146         int fit = (num_sectors == 0);
6147
6148         if (mddev->pers->resize == NULL)
6149                 return -EINVAL;
6150         /* The "num_sectors" is the number of sectors of each device that
6151          * is used.  This can only make sense for arrays with redundancy.
6152          * linear and raid0 always use whatever space is available. We can only
6153          * consider changing this number if no resync or reconstruction is
6154          * happening, and if the new size is acceptable. It must fit before the
6155          * sb_start or, if that is <data_offset, it must fit before the size
6156          * of each device.  If num_sectors is zero, we find the largest size
6157          * that fits.
6158          */
6159         if (mddev->sync_thread)
6160                 return -EBUSY;
6161
6162         rdev_for_each(rdev, mddev) {
6163                 sector_t avail = rdev->sectors;
6164
6165                 if (fit && (num_sectors == 0 || num_sectors > avail))
6166                         num_sectors = avail;
6167                 if (avail < num_sectors)
6168                         return -ENOSPC;
6169         }
6170         rv = mddev->pers->resize(mddev, num_sectors);
6171         if (!rv)
6172                 revalidate_disk(mddev->gendisk);
6173         return rv;
6174 }
6175
6176 static int update_raid_disks(struct mddev *mddev, int raid_disks)
6177 {
6178         int rv;
6179         struct md_rdev *rdev;
6180         /* change the number of raid disks */
6181         if (mddev->pers->check_reshape == NULL)
6182                 return -EINVAL;
6183         if (raid_disks <= 0 ||
6184             (mddev->max_disks && raid_disks >= mddev->max_disks))
6185                 return -EINVAL;
6186         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
6187                 return -EBUSY;
6188
6189         rdev_for_each(rdev, mddev) {
6190                 if (mddev->raid_disks < raid_disks &&
6191                     rdev->data_offset < rdev->new_data_offset)
6192                         return -EINVAL;
6193                 if (mddev->raid_disks > raid_disks &&
6194                     rdev->data_offset > rdev->new_data_offset)
6195                         return -EINVAL;
6196         }
6197
6198         mddev->delta_disks = raid_disks - mddev->raid_disks;
6199         if (mddev->delta_disks < 0)
6200                 mddev->reshape_backwards = 1;
6201         else if (mddev->delta_disks > 0)
6202                 mddev->reshape_backwards = 0;
6203
6204         rv = mddev->pers->check_reshape(mddev);
6205         if (rv < 0) {
6206                 mddev->delta_disks = 0;
6207                 mddev->reshape_backwards = 0;
6208         }
6209         return rv;
6210 }
6211
6212
6213 /*
6214  * update_array_info is used to change the configuration of an
6215  * on-line array.
6216  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
6217  * fields in the info are checked against the array.
6218  * Any differences that cannot be handled will cause an error.
6219  * Normally, only one change can be managed at a time.
6220  */
6221 static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
6222 {
6223         int rv = 0;
6224         int cnt = 0;
6225         int state = 0;
6226
6227         /* calculate expected state,ignoring low bits */
6228         if (mddev->bitmap && mddev->bitmap_info.offset)
6229                 state |= (1 << MD_SB_BITMAP_PRESENT);
6230
6231         if (mddev->major_version != info->major_version ||
6232             mddev->minor_version != info->minor_version ||
6233 /*          mddev->patch_version != info->patch_version || */
6234             mddev->ctime         != info->ctime         ||
6235             mddev->level         != info->level         ||
6236 /*          mddev->layout        != info->layout        || */
6237             !mddev->persistent   != info->not_persistent||
6238             mddev->chunk_sectors != info->chunk_size >> 9 ||
6239             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
6240             ((state^info->state) & 0xfffffe00)
6241                 )
6242                 return -EINVAL;
6243         /* Check there is only one change */
6244         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
6245                 cnt++;
6246         if (mddev->raid_disks != info->raid_disks)
6247                 cnt++;
6248         if (mddev->layout != info->layout)
6249                 cnt++;
6250         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT))
6251                 cnt++;
6252         if (cnt == 0)
6253                 return 0;
6254         if (cnt > 1)
6255                 return -EINVAL;
6256
6257         if (mddev->layout != info->layout) {
6258                 /* Change layout
6259                  * we don't need to do anything at the md level, the
6260                  * personality will take care of it all.
6261                  */
6262                 if (mddev->pers->check_reshape == NULL)
6263                         return -EINVAL;
6264                 else {
6265                         mddev->new_layout = info->layout;
6266                         rv = mddev->pers->check_reshape(mddev);
6267                         if (rv)
6268                                 mddev->new_layout = mddev->layout;
6269                         return rv;
6270                 }
6271         }
6272         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
6273                 rv = update_size(mddev, (sector_t)info->size * 2);
6274
6275         if (mddev->raid_disks    != info->raid_disks)
6276                 rv = update_raid_disks(mddev, info->raid_disks);
6277
6278         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
6279                 if (mddev->pers->quiesce == NULL)
6280                         return -EINVAL;
6281                 if (mddev->recovery || mddev->sync_thread)
6282                         return -EBUSY;
6283                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
6284                         /* add the bitmap */
6285                         if (mddev->bitmap)
6286                                 return -EEXIST;
6287                         if (mddev->bitmap_info.default_offset == 0)
6288                                 return -EINVAL;
6289                         mddev->bitmap_info.offset =
6290                                 mddev->bitmap_info.default_offset;
6291                         mddev->bitmap_info.space =
6292                                 mddev->bitmap_info.default_space;
6293                         mddev->pers->quiesce(mddev, 1);
6294                         rv = bitmap_create(mddev);
6295                         if (!rv)
6296                                 rv = bitmap_load(mddev);
6297                         if (rv)
6298                                 bitmap_destroy(mddev);
6299                         mddev->pers->quiesce(mddev, 0);
6300                 } else {
6301                         /* remove the bitmap */
6302                         if (!mddev->bitmap)
6303                                 return -ENOENT;
6304                         if (mddev->bitmap->storage.file)
6305                                 return -EINVAL;
6306                         mddev->pers->quiesce(mddev, 1);
6307                         bitmap_destroy(mddev);
6308                         mddev->pers->quiesce(mddev, 0);
6309                         mddev->bitmap_info.offset = 0;
6310                 }
6311         }
6312         md_update_sb(mddev, 1);
6313         return rv;
6314 }
6315
6316 static int set_disk_faulty(struct mddev *mddev, dev_t dev)
6317 {
6318         struct md_rdev *rdev;
6319
6320         if (mddev->pers == NULL)
6321                 return -ENODEV;
6322
6323         rdev = find_rdev(mddev, dev);
6324         if (!rdev)
6325                 return -ENODEV;
6326
6327         md_error(mddev, rdev);
6328         if (!test_bit(Faulty, &rdev->flags))
6329                 return -EBUSY;
6330         return 0;
6331 }
6332
6333 /*
6334  * We have a problem here : there is no easy way to give a CHS
6335  * virtual geometry. We currently pretend that we have a 2 heads
6336  * 4 sectors (with a BIG number of cylinders...). This drives
6337  * dosfs just mad... ;-)
6338  */
6339 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
6340 {
6341         struct mddev *mddev = bdev->bd_disk->private_data;
6342
6343         geo->heads = 2;
6344         geo->sectors = 4;
6345         geo->cylinders = mddev->array_sectors / 8;
6346         return 0;
6347 }
6348
6349 static int md_ioctl(struct block_device *bdev, fmode_t mode,
6350                         unsigned int cmd, unsigned long arg)
6351 {
6352         int err = 0;
6353         void __user *argp = (void __user *)arg;
6354         struct mddev *mddev = NULL;
6355         int ro;
6356
6357         switch (cmd) {
6358         case RAID_VERSION:
6359         case GET_ARRAY_INFO:
6360         case GET_DISK_INFO:
6361                 break;
6362         default:
6363                 if (!capable(CAP_SYS_ADMIN))
6364                         return -EACCES;
6365         }
6366
6367         /*
6368          * Commands dealing with the RAID driver but not any
6369          * particular array:
6370          */
6371         switch (cmd)
6372         {
6373                 case RAID_VERSION:
6374                         err = get_version(argp);
6375                         goto done;
6376
6377                 case PRINT_RAID_DEBUG:
6378                         err = 0;
6379                         md_print_devices();
6380                         goto done;
6381
6382 #ifndef MODULE
6383                 case RAID_AUTORUN:
6384                         err = 0;
6385                         autostart_arrays(arg);
6386                         goto done;
6387 #endif
6388                 default:;
6389         }
6390
6391         /*
6392          * Commands creating/starting a new array:
6393          */
6394
6395         mddev = bdev->bd_disk->private_data;
6396
6397         if (!mddev) {
6398                 BUG();
6399                 goto abort;
6400         }
6401
6402         err = mddev_lock(mddev);
6403         if (err) {
6404                 printk(KERN_INFO
6405                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
6406                         err, cmd);
6407                 goto abort;
6408         }
6409
6410         switch (cmd)
6411         {
6412                 case SET_ARRAY_INFO:
6413                         {
6414                                 mdu_array_info_t info;
6415                                 if (!arg)
6416                                         memset(&info, 0, sizeof(info));
6417                                 else if (copy_from_user(&info, argp, sizeof(info))) {
6418                                         err = -EFAULT;
6419                                         goto abort_unlock;
6420                                 }
6421                                 if (mddev->pers) {
6422                                         err = update_array_info(mddev, &info);
6423                                         if (err) {
6424                                                 printk(KERN_WARNING "md: couldn't update"
6425                                                        " array info. %d\n", err);
6426                                                 goto abort_unlock;
6427                                         }
6428                                         goto done_unlock;
6429                                 }
6430                                 if (!list_empty(&mddev->disks)) {
6431                                         printk(KERN_WARNING
6432                                                "md: array %s already has disks!\n",
6433                                                mdname(mddev));
6434                                         err = -EBUSY;
6435                                         goto abort_unlock;
6436                                 }
6437                                 if (mddev->raid_disks) {
6438                                         printk(KERN_WARNING
6439                                                "md: array %s already initialised!\n",
6440                                                mdname(mddev));
6441                                         err = -EBUSY;
6442                                         goto abort_unlock;
6443                                 }
6444                                 err = set_array_info(mddev, &info);
6445                                 if (err) {
6446                                         printk(KERN_WARNING "md: couldn't set"
6447                                                " array info. %d\n", err);
6448                                         goto abort_unlock;
6449                                 }
6450                         }
6451                         goto done_unlock;
6452
6453                 default:;
6454         }
6455
6456         /*
6457          * Commands querying/configuring an existing array:
6458          */
6459         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
6460          * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
6461         if ((!mddev->raid_disks && !mddev->external)
6462             && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
6463             && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
6464             && cmd != GET_BITMAP_FILE) {
6465                 err = -ENODEV;
6466                 goto abort_unlock;
6467         }
6468
6469         /*
6470          * Commands even a read-only array can execute:
6471          */
6472         switch (cmd)
6473         {
6474                 case GET_ARRAY_INFO:
6475                         err = get_array_info(mddev, argp);
6476                         goto done_unlock;
6477
6478                 case GET_BITMAP_FILE:
6479                         err = get_bitmap_file(mddev, argp);
6480                         goto done_unlock;
6481
6482                 case GET_DISK_INFO:
6483                         err = get_disk_info(mddev, argp);
6484                         goto done_unlock;
6485
6486                 case RESTART_ARRAY_RW:
6487                         err = restart_array(mddev);
6488                         goto done_unlock;
6489
6490                 case STOP_ARRAY:
6491                         err = do_md_stop(mddev, 0, bdev);
6492                         goto done_unlock;
6493
6494                 case STOP_ARRAY_RO:
6495                         err = md_set_readonly(mddev, bdev);
6496                         goto done_unlock;
6497
6498                 case BLKROSET:
6499                         if (get_user(ro, (int __user *)(arg))) {
6500                                 err = -EFAULT;
6501                                 goto done_unlock;
6502                         }
6503                         err = -EINVAL;
6504
6505                         /* if the bdev is going readonly the value of mddev->ro
6506                          * does not matter, no writes are coming
6507                          */
6508                         if (ro)
6509                                 goto done_unlock;
6510
6511                         /* are we are already prepared for writes? */
6512                         if (mddev->ro != 1)
6513                                 goto done_unlock;
6514
6515                         /* transitioning to readauto need only happen for
6516                          * arrays that call md_write_start
6517                          */
6518                         if (mddev->pers) {
6519                                 err = restart_array(mddev);
6520                                 if (err == 0) {
6521                                         mddev->ro = 2;
6522                                         set_disk_ro(mddev->gendisk, 0);
6523                                 }
6524                         }
6525                         goto done_unlock;
6526         }
6527
6528         /*
6529          * The remaining ioctls are changing the state of the
6530          * superblock, so we do not allow them on read-only arrays.
6531          * However non-MD ioctls (e.g. get-size) will still come through
6532          * here and hit the 'default' below, so only disallow
6533          * 'md' ioctls, and switch to rw mode if started auto-readonly.
6534          */
6535         if (_IOC_TYPE(cmd) == MD_MAJOR && mddev->ro && mddev->pers) {
6536                 if (mddev->ro == 2) {
6537                         mddev->ro = 0;
6538                         sysfs_notify_dirent_safe(mddev->sysfs_state);
6539                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6540                         md_wakeup_thread(mddev->thread);
6541                 } else {
6542                         err = -EROFS;
6543                         goto abort_unlock;
6544                 }
6545         }
6546
6547         switch (cmd)
6548         {
6549                 case ADD_NEW_DISK:
6550                 {
6551                         mdu_disk_info_t info;
6552                         if (copy_from_user(&info, argp, sizeof(info)))
6553                                 err = -EFAULT;
6554                         else
6555                                 err = add_new_disk(mddev, &info);
6556                         goto done_unlock;
6557                 }
6558
6559                 case HOT_REMOVE_DISK:
6560                         err = hot_remove_disk(mddev, new_decode_dev(arg));
6561                         goto done_unlock;
6562
6563                 case HOT_ADD_DISK:
6564                         err = hot_add_disk(mddev, new_decode_dev(arg));
6565                         goto done_unlock;
6566
6567                 case SET_DISK_FAULTY:
6568                         err = set_disk_faulty(mddev, new_decode_dev(arg));
6569                         goto done_unlock;
6570
6571                 case RUN_ARRAY:
6572                         err = do_md_run(mddev);
6573                         goto done_unlock;
6574
6575                 case SET_BITMAP_FILE:
6576                         err = set_bitmap_file(mddev, (int)arg);
6577                         goto done_unlock;
6578
6579                 default:
6580                         err = -EINVAL;
6581                         goto abort_unlock;
6582         }
6583
6584 done_unlock:
6585 abort_unlock:
6586         if (mddev->hold_active == UNTIL_IOCTL &&
6587             err != -EINVAL)
6588                 mddev->hold_active = 0;
6589         mddev_unlock(mddev);
6590
6591         return err;
6592 done:
6593         if (err)
6594                 MD_BUG();
6595 abort:
6596         return err;
6597 }
6598 #ifdef CONFIG_COMPAT
6599 static int md_compat_ioctl(struct block_device *bdev, fmode_t mode,
6600                     unsigned int cmd, unsigned long arg)
6601 {
6602         switch (cmd) {
6603         case HOT_REMOVE_DISK:
6604         case HOT_ADD_DISK:
6605         case SET_DISK_FAULTY:
6606         case SET_BITMAP_FILE:
6607                 /* These take in integer arg, do not convert */
6608                 break;
6609         default:
6610                 arg = (unsigned long)compat_ptr(arg);
6611                 break;
6612         }
6613
6614         return md_ioctl(bdev, mode, cmd, arg);
6615 }
6616 #endif /* CONFIG_COMPAT */
6617
6618 static int md_open(struct block_device *bdev, fmode_t mode)
6619 {
6620         /*
6621          * Succeed if we can lock the mddev, which confirms that
6622          * it isn't being stopped right now.
6623          */
6624         struct mddev *mddev = mddev_find(bdev->bd_dev);
6625         int err;
6626
6627         if (!mddev)
6628                 return -ENODEV;
6629
6630         if (mddev->gendisk != bdev->bd_disk) {
6631                 /* we are racing with mddev_put which is discarding this
6632                  * bd_disk.
6633                  */
6634                 mddev_put(mddev);
6635                 /* Wait until bdev->bd_disk is definitely gone */
6636                 flush_workqueue(md_misc_wq);
6637                 /* Then retry the open from the top */
6638                 return -ERESTARTSYS;
6639         }
6640         BUG_ON(mddev != bdev->bd_disk->private_data);
6641
6642         if ((err = mutex_lock_interruptible(&mddev->open_mutex)))
6643                 goto out;
6644
6645         err = 0;
6646         atomic_inc(&mddev->openers);
6647         mutex_unlock(&mddev->open_mutex);
6648
6649         check_disk_change(bdev);
6650  out:
6651         return err;
6652 }
6653
6654 static int md_release(struct gendisk *disk, fmode_t mode)
6655 {
6656         struct mddev *mddev = disk->private_data;
6657
6658         BUG_ON(!mddev);
6659         atomic_dec(&mddev->openers);
6660         mddev_put(mddev);
6661
6662         return 0;
6663 }
6664
6665 static int md_media_changed(struct gendisk *disk)
6666 {
6667         struct mddev *mddev = disk->private_data;
6668
6669         return mddev->changed;
6670 }
6671
6672 static int md_revalidate(struct gendisk *disk)
6673 {
6674         struct mddev *mddev = disk->private_data;
6675
6676         mddev->changed = 0;
6677         return 0;
6678 }
6679 static const struct block_device_operations md_fops =
6680 {
6681         .owner          = THIS_MODULE,
6682         .open           = md_open,
6683         .release        = md_release,
6684         .ioctl          = md_ioctl,
6685 #ifdef CONFIG_COMPAT
6686         .compat_ioctl   = md_compat_ioctl,
6687 #endif
6688         .getgeo         = md_getgeo,
6689         .media_changed  = md_media_changed,
6690         .revalidate_disk= md_revalidate,
6691 };
6692
6693 static int md_thread(void * arg)
6694 {
6695         struct md_thread *thread = arg;
6696
6697         /*
6698          * md_thread is a 'system-thread', it's priority should be very
6699          * high. We avoid resource deadlocks individually in each
6700          * raid personality. (RAID5 does preallocation) We also use RR and
6701          * the very same RT priority as kswapd, thus we will never get
6702          * into a priority inversion deadlock.
6703          *
6704          * we definitely have to have equal or higher priority than
6705          * bdflush, otherwise bdflush will deadlock if there are too
6706          * many dirty RAID5 blocks.
6707          */
6708
6709         allow_signal(SIGKILL);
6710         while (!kthread_should_stop()) {
6711
6712                 /* We need to wait INTERRUPTIBLE so that
6713                  * we don't add to the load-average.
6714                  * That means we need to be sure no signals are
6715                  * pending
6716                  */
6717                 if (signal_pending(current))
6718                         flush_signals(current);
6719
6720                 wait_event_interruptible_timeout
6721                         (thread->wqueue,
6722                          test_bit(THREAD_WAKEUP, &thread->flags)
6723                          || kthread_should_stop(),
6724                          thread->timeout);
6725
6726                 clear_bit(THREAD_WAKEUP, &thread->flags);
6727                 if (!kthread_should_stop())
6728                         thread->run(thread->mddev);
6729         }
6730
6731         return 0;
6732 }
6733
6734 void md_wakeup_thread(struct md_thread *thread)
6735 {
6736         if (thread) {
6737                 pr_debug("md: waking up MD thread %s.\n", thread->tsk->comm);
6738                 set_bit(THREAD_WAKEUP, &thread->flags);
6739                 wake_up(&thread->wqueue);
6740         }
6741 }
6742
6743 struct md_thread *md_register_thread(void (*run) (struct mddev *), struct mddev *mddev,
6744                                  const char *name)
6745 {
6746         struct md_thread *thread;
6747
6748         thread = kzalloc(sizeof(struct md_thread), GFP_KERNEL);
6749         if (!thread)
6750                 return NULL;
6751
6752         init_waitqueue_head(&thread->wqueue);
6753
6754         thread->run = run;
6755         thread->mddev = mddev;
6756         thread->timeout = MAX_SCHEDULE_TIMEOUT;
6757         thread->tsk = kthread_run(md_thread, thread,
6758                                   "%s_%s",
6759                                   mdname(thread->mddev),
6760                                   name);
6761         if (IS_ERR(thread->tsk)) {
6762                 kfree(thread);
6763                 return NULL;
6764         }
6765         return thread;
6766 }
6767
6768 void md_unregister_thread(struct md_thread **threadp)
6769 {
6770         struct md_thread *thread = *threadp;
6771         if (!thread)
6772                 return;
6773         pr_debug("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
6774         /* Locking ensures that mddev_unlock does not wake_up a
6775          * non-existent thread
6776          */
6777         spin_lock(&pers_lock);
6778         *threadp = NULL;
6779         spin_unlock(&pers_lock);
6780
6781         kthread_stop(thread->tsk);
6782         kfree(thread);
6783 }
6784
6785 void md_error(struct mddev *mddev, struct md_rdev *rdev)
6786 {
6787         if (!mddev) {
6788                 MD_BUG();
6789                 return;
6790         }
6791
6792         if (!rdev || test_bit(Faulty, &rdev->flags))
6793                 return;
6794
6795         if (!mddev->pers || !mddev->pers->error_handler)
6796                 return;
6797         mddev->pers->error_handler(mddev,rdev);
6798         if (mddev->degraded)
6799                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
6800         sysfs_notify_dirent_safe(rdev->sysfs_state);
6801         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
6802         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6803         md_wakeup_thread(mddev->thread);
6804         if (mddev->event_work.func)
6805                 queue_work(md_misc_wq, &mddev->event_work);
6806         md_new_event_inintr(mddev);
6807 }
6808
6809 /* seq_file implementation /proc/mdstat */
6810
6811 static void status_unused(struct seq_file *seq)
6812 {
6813         int i = 0;
6814         struct md_rdev *rdev;
6815
6816         seq_printf(seq, "unused devices: ");
6817
6818         list_for_each_entry(rdev, &pending_raid_disks, same_set) {
6819                 char b[BDEVNAME_SIZE];
6820                 i++;
6821                 seq_printf(seq, "%s ",
6822                               bdevname(rdev->bdev,b));
6823         }
6824         if (!i)
6825                 seq_printf(seq, "<none>");
6826
6827         seq_printf(seq, "\n");
6828 }
6829
6830
6831 static void status_resync(struct seq_file *seq, struct mddev * mddev)
6832 {
6833         sector_t max_sectors, resync, res;
6834         unsigned long dt, db;
6835         sector_t rt;
6836         int scale;
6837         unsigned int per_milli;
6838
6839         resync = mddev->curr_resync - atomic_read(&mddev->recovery_active);
6840
6841         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
6842             test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
6843                 max_sectors = mddev->resync_max_sectors;
6844         else
6845                 max_sectors = mddev->dev_sectors;
6846
6847         /*
6848          * Should not happen.
6849          */
6850         if (!max_sectors) {
6851                 MD_BUG();
6852                 return;
6853         }
6854         /* Pick 'scale' such that (resync>>scale)*1000 will fit
6855          * in a sector_t, and (max_sectors>>scale) will fit in a
6856          * u32, as those are the requirements for sector_div.
6857          * Thus 'scale' must be at least 10
6858          */
6859         scale = 10;
6860         if (sizeof(sector_t) > sizeof(unsigned long)) {
6861                 while ( max_sectors/2 > (1ULL<<(scale+32)))
6862                         scale++;
6863         }
6864         res = (resync>>scale)*1000;
6865         sector_div(res, (u32)((max_sectors>>scale)+1));
6866
6867         per_milli = res;
6868         {
6869                 int i, x = per_milli/50, y = 20-x;
6870                 seq_printf(seq, "[");
6871                 for (i = 0; i < x; i++)
6872                         seq_printf(seq, "=");
6873                 seq_printf(seq, ">");
6874                 for (i = 0; i < y; i++)
6875                         seq_printf(seq, ".");
6876                 seq_printf(seq, "] ");
6877         }
6878         seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
6879                    (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
6880                     "reshape" :
6881                     (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
6882                      "check" :
6883                      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
6884                       "resync" : "recovery"))),
6885                    per_milli/10, per_milli % 10,
6886                    (unsigned long long) resync/2,
6887                    (unsigned long long) max_sectors/2);
6888
6889         /*
6890          * dt: time from mark until now
6891          * db: blocks written from mark until now
6892          * rt: remaining time
6893          *
6894          * rt is a sector_t, so could be 32bit or 64bit.
6895          * So we divide before multiply in case it is 32bit and close
6896          * to the limit.
6897          * We scale the divisor (db) by 32 to avoid losing precision
6898          * near the end of resync when the number of remaining sectors
6899          * is close to 'db'.
6900          * We then divide rt by 32 after multiplying by db to compensate.
6901          * The '+1' avoids division by zero if db is very small.
6902          */
6903         dt = ((jiffies - mddev->resync_mark) / HZ);
6904         if (!dt) dt++;
6905         db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active))
6906                 - mddev->resync_mark_cnt;
6907
6908         rt = max_sectors - resync;    /* number of remaining sectors */
6909         sector_div(rt, db/32+1);
6910         rt *= dt;
6911         rt >>= 5;
6912
6913         seq_printf(seq, " finish=%lu.%lumin", (unsigned long)rt / 60,
6914                    ((unsigned long)rt % 60)/6);
6915
6916         seq_printf(seq, " speed=%ldK/sec", db/2/dt);
6917 }
6918
6919 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
6920 {
6921         struct list_head *tmp;
6922         loff_t l = *pos;
6923         struct mddev *mddev;
6924
6925         if (l >= 0x10000)
6926                 return NULL;
6927         if (!l--)
6928                 /* header */
6929                 return (void*)1;
6930
6931         spin_lock(&all_mddevs_lock);
6932         list_for_each(tmp,&all_mddevs)
6933                 if (!l--) {
6934                         mddev = list_entry(tmp, struct mddev, all_mddevs);
6935                         mddev_get(mddev);
6936                         spin_unlock(&all_mddevs_lock);
6937                         return mddev;
6938                 }
6939         spin_unlock(&all_mddevs_lock);
6940         if (!l--)
6941                 return (void*)2;/* tail */
6942         return NULL;
6943 }
6944
6945 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
6946 {
6947         struct list_head *tmp;
6948         struct mddev *next_mddev, *mddev = v;
6949
6950         ++*pos;
6951         if (v == (void*)2)
6952                 return NULL;
6953
6954         spin_lock(&all_mddevs_lock);
6955         if (v == (void*)1)
6956                 tmp = all_mddevs.next;
6957         else
6958                 tmp = mddev->all_mddevs.next;
6959         if (tmp != &all_mddevs)
6960                 next_mddev = mddev_get(list_entry(tmp,struct mddev,all_mddevs));
6961         else {
6962                 next_mddev = (void*)2;
6963                 *pos = 0x10000;
6964         }
6965         spin_unlock(&all_mddevs_lock);
6966
6967         if (v != (void*)1)
6968                 mddev_put(mddev);
6969         return next_mddev;
6970
6971 }
6972
6973 static void md_seq_stop(struct seq_file *seq, void *v)
6974 {
6975         struct mddev *mddev = v;
6976
6977         if (mddev && v != (void*)1 && v != (void*)2)
6978                 mddev_put(mddev);
6979 }
6980
6981 static int md_seq_show(struct seq_file *seq, void *v)
6982 {
6983         struct mddev *mddev = v;
6984         sector_t sectors;
6985         struct md_rdev *rdev;
6986
6987         if (v == (void*)1) {
6988                 struct md_personality *pers;
6989                 seq_printf(seq, "Personalities : ");
6990                 spin_lock(&pers_lock);
6991                 list_for_each_entry(pers, &pers_list, list)
6992                         seq_printf(seq, "[%s] ", pers->name);
6993
6994                 spin_unlock(&pers_lock);
6995                 seq_printf(seq, "\n");
6996                 seq->poll_event = atomic_read(&md_event_count);
6997                 return 0;
6998         }
6999         if (v == (void*)2) {
7000                 status_unused(seq);
7001                 return 0;
7002         }
7003
7004         if (mddev_lock(mddev) < 0)
7005                 return -EINTR;
7006
7007         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
7008                 seq_printf(seq, "%s : %sactive", mdname(mddev),
7009                                                 mddev->pers ? "" : "in");
7010                 if (mddev->pers) {
7011                         if (mddev->ro==1)
7012                                 seq_printf(seq, " (read-only)");
7013                         if (mddev->ro==2)
7014                                 seq_printf(seq, " (auto-read-only)");
7015                         seq_printf(seq, " %s", mddev->pers->name);
7016                 }
7017
7018                 sectors = 0;
7019                 rdev_for_each(rdev, mddev) {
7020                         char b[BDEVNAME_SIZE];
7021                         seq_printf(seq, " %s[%d]",
7022                                 bdevname(rdev->bdev,b), rdev->desc_nr);
7023                         if (test_bit(WriteMostly, &rdev->flags))
7024                                 seq_printf(seq, "(W)");
7025                         if (test_bit(Faulty, &rdev->flags)) {
7026                                 seq_printf(seq, "(F)");
7027                                 continue;
7028                         }
7029                         if (rdev->raid_disk < 0)
7030                                 seq_printf(seq, "(S)"); /* spare */
7031                         if (test_bit(Replacement, &rdev->flags))
7032                                 seq_printf(seq, "(R)");
7033                         sectors += rdev->sectors;
7034                 }
7035
7036                 if (!list_empty(&mddev->disks)) {
7037                         if (mddev->pers)
7038                                 seq_printf(seq, "\n      %llu blocks",
7039                                            (unsigned long long)
7040                                            mddev->array_sectors / 2);
7041                         else
7042                                 seq_printf(seq, "\n      %llu blocks",
7043                                            (unsigned long long)sectors / 2);
7044                 }
7045                 if (mddev->persistent) {
7046                         if (mddev->major_version != 0 ||
7047                             mddev->minor_version != 90) {
7048                                 seq_printf(seq," super %d.%d",
7049                                            mddev->major_version,
7050                                            mddev->minor_version);
7051                         }
7052                 } else if (mddev->external)
7053                         seq_printf(seq, " super external:%s",
7054                                    mddev->metadata_type);
7055                 else
7056                         seq_printf(seq, " super non-persistent");
7057
7058                 if (mddev->pers) {
7059                         mddev->pers->status(seq, mddev);
7060                         seq_printf(seq, "\n      ");
7061                         if (mddev->pers->sync_request) {
7062                                 if (mddev->curr_resync > 2) {
7063                                         status_resync(seq, mddev);
7064                                         seq_printf(seq, "\n      ");
7065                                 } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
7066                                         seq_printf(seq, "\tresync=DELAYED\n      ");
7067                                 else if (mddev->recovery_cp < MaxSector)
7068                                         seq_printf(seq, "\tresync=PENDING\n      ");
7069                         }
7070                 } else
7071                         seq_printf(seq, "\n       ");
7072
7073                 bitmap_status(seq, mddev->bitmap);
7074
7075                 seq_printf(seq, "\n");
7076         }
7077         mddev_unlock(mddev);
7078
7079         return 0;
7080 }
7081
7082 static const struct seq_operations md_seq_ops = {
7083         .start  = md_seq_start,
7084         .next   = md_seq_next,
7085         .stop   = md_seq_stop,
7086         .show   = md_seq_show,
7087 };
7088
7089 static int md_seq_open(struct inode *inode, struct file *file)
7090 {
7091         struct seq_file *seq;
7092         int error;
7093
7094         error = seq_open(file, &md_seq_ops);
7095         if (error)
7096                 return error;
7097
7098         seq = file->private_data;
7099         seq->poll_event = atomic_read(&md_event_count);
7100         return error;
7101 }
7102
7103 static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
7104 {
7105         struct seq_file *seq = filp->private_data;
7106         int mask;
7107
7108         poll_wait(filp, &md_event_waiters, wait);
7109
7110         /* always allow read */
7111         mask = POLLIN | POLLRDNORM;
7112
7113         if (seq->poll_event != atomic_read(&md_event_count))
7114                 mask |= POLLERR | POLLPRI;
7115         return mask;
7116 }
7117
7118 static const struct file_operations md_seq_fops = {
7119         .owner          = THIS_MODULE,
7120         .open           = md_seq_open,
7121         .read           = seq_read,
7122         .llseek         = seq_lseek,
7123         .release        = seq_release_private,
7124         .poll           = mdstat_poll,
7125 };
7126
7127 int register_md_personality(struct md_personality *p)
7128 {
7129         spin_lock(&pers_lock);
7130         list_add_tail(&p->list, &pers_list);
7131         printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
7132         spin_unlock(&pers_lock);
7133         return 0;
7134 }
7135
7136 int unregister_md_personality(struct md_personality *p)
7137 {
7138         printk(KERN_INFO "md: %s personality unregistered\n", p->name);
7139         spin_lock(&pers_lock);
7140         list_del_init(&p->list);
7141         spin_unlock(&pers_lock);
7142         return 0;
7143 }
7144
7145 static int is_mddev_idle(struct mddev *mddev, int init)
7146 {
7147         struct md_rdev * rdev;
7148         int idle;
7149         int curr_events;
7150
7151         idle = 1;
7152         rcu_read_lock();
7153         rdev_for_each_rcu(rdev, mddev) {
7154                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
7155                 curr_events = (int)part_stat_read(&disk->part0, sectors[0]) +
7156                               (int)part_stat_read(&disk->part0, sectors[1]) -
7157                               atomic_read(&disk->sync_io);
7158                 /* sync IO will cause sync_io to increase before the disk_stats
7159                  * as sync_io is counted when a request starts, and
7160                  * disk_stats is counted when it completes.
7161                  * So resync activity will cause curr_events to be smaller than
7162                  * when there was no such activity.
7163                  * non-sync IO will cause disk_stat to increase without
7164                  * increasing sync_io so curr_events will (eventually)
7165                  * be larger than it was before.  Once it becomes
7166                  * substantially larger, the test below will cause
7167                  * the array to appear non-idle, and resync will slow
7168                  * down.
7169                  * If there is a lot of outstanding resync activity when
7170                  * we set last_event to curr_events, then all that activity
7171                  * completing might cause the array to appear non-idle
7172                  * and resync will be slowed down even though there might
7173                  * not have been non-resync activity.  This will only
7174                  * happen once though.  'last_events' will soon reflect
7175                  * the state where there is little or no outstanding
7176                  * resync requests, and further resync activity will
7177                  * always make curr_events less than last_events.
7178                  *
7179                  */
7180                 if (init || curr_events - rdev->last_events > 64) {
7181                         rdev->last_events = curr_events;
7182                         idle = 0;
7183                 }
7184         }
7185         rcu_read_unlock();
7186         return idle;
7187 }
7188
7189 void md_done_sync(struct mddev *mddev, int blocks, int ok)
7190 {
7191         /* another "blocks" (512byte) blocks have been synced */
7192         atomic_sub(blocks, &mddev->recovery_active);
7193         wake_up(&mddev->recovery_wait);
7194         if (!ok) {
7195                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7196                 md_wakeup_thread(mddev->thread);
7197                 // stop recovery, signal do_sync ....
7198         }
7199 }
7200
7201
7202 /* md_write_start(mddev, bi)
7203  * If we need to update some array metadata (e.g. 'active' flag
7204  * in superblock) before writing, schedule a superblock update
7205  * and wait for it to complete.
7206  */
7207 void md_write_start(struct mddev *mddev, struct bio *bi)
7208 {
7209         int did_change = 0;
7210         if (bio_data_dir(bi) != WRITE)
7211                 return;
7212
7213         BUG_ON(mddev->ro == 1);
7214         if (mddev->ro == 2) {
7215                 /* need to switch to read/write */
7216                 mddev->ro = 0;
7217                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7218                 md_wakeup_thread(mddev->thread);
7219                 md_wakeup_thread(mddev->sync_thread);
7220                 did_change = 1;
7221         }
7222         atomic_inc(&mddev->writes_pending);
7223         if (mddev->safemode == 1)
7224                 mddev->safemode = 0;
7225         if (mddev->in_sync) {
7226                 spin_lock_irq(&mddev->write_lock);
7227                 if (mddev->in_sync) {
7228                         mddev->in_sync = 0;
7229                         set_bit(MD_CHANGE_CLEAN, &mddev->flags);
7230                         set_bit(MD_CHANGE_PENDING, &mddev->flags);
7231                         md_wakeup_thread(mddev->thread);
7232                         did_change = 1;
7233                 }
7234                 spin_unlock_irq(&mddev->write_lock);
7235         }
7236         if (did_change)
7237                 sysfs_notify_dirent_safe(mddev->sysfs_state);
7238         wait_event(mddev->sb_wait,
7239                    !test_bit(MD_CHANGE_PENDING, &mddev->flags));
7240 }
7241
7242 void md_write_end(struct mddev *mddev)
7243 {
7244         if (atomic_dec_and_test(&mddev->writes_pending)) {
7245                 if (mddev->safemode == 2)
7246                         md_wakeup_thread(mddev->thread);
7247                 else if (mddev->safemode_delay)
7248                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
7249         }
7250 }
7251
7252 /* md_allow_write(mddev)
7253  * Calling this ensures that the array is marked 'active' so that writes
7254  * may proceed without blocking.  It is important to call this before
7255  * attempting a GFP_KERNEL allocation while holding the mddev lock.
7256  * Must be called with mddev_lock held.
7257  *
7258  * In the ->external case MD_CHANGE_CLEAN can not be cleared until mddev->lock
7259  * is dropped, so return -EAGAIN after notifying userspace.
7260  */
7261 int md_allow_write(struct mddev *mddev)
7262 {
7263         if (!mddev->pers)
7264                 return 0;
7265         if (mddev->ro)
7266                 return 0;
7267         if (!mddev->pers->sync_request)
7268                 return 0;
7269
7270         spin_lock_irq(&mddev->write_lock);
7271         if (mddev->in_sync) {
7272                 mddev->in_sync = 0;
7273                 set_bit(MD_CHANGE_CLEAN, &mddev->flags);
7274                 set_bit(MD_CHANGE_PENDING, &mddev->flags);
7275                 if (mddev->safemode_delay &&
7276                     mddev->safemode == 0)
7277                         mddev->safemode = 1;
7278                 spin_unlock_irq(&mddev->write_lock);
7279                 md_update_sb(mddev, 0);
7280                 sysfs_notify_dirent_safe(mddev->sysfs_state);
7281         } else
7282                 spin_unlock_irq(&mddev->write_lock);
7283
7284         if (test_bit(MD_CHANGE_PENDING, &mddev->flags))
7285                 return -EAGAIN;
7286         else
7287                 return 0;
7288 }
7289 EXPORT_SYMBOL_GPL(md_allow_write);
7290
7291 #define SYNC_MARKS      10
7292 #define SYNC_MARK_STEP  (3*HZ)
7293 void md_do_sync(struct mddev *mddev)
7294 {
7295         struct mddev *mddev2;
7296         unsigned int currspeed = 0,
7297                  window;
7298         sector_t max_sectors,j, io_sectors;
7299         unsigned long mark[SYNC_MARKS];
7300         sector_t mark_cnt[SYNC_MARKS];
7301         int last_mark,m;
7302         struct list_head *tmp;
7303         sector_t last_check;
7304         int skipped = 0;
7305         struct md_rdev *rdev;
7306         char *desc;
7307         struct blk_plug plug;
7308
7309         /* just incase thread restarts... */
7310         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
7311                 return;
7312         if (mddev->ro) /* never try to sync a read-only array */
7313                 return;
7314
7315         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
7316                 if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
7317                         desc = "data-check";
7318                 else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7319                         desc = "requested-resync";
7320                 else
7321                         desc = "resync";
7322         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
7323                 desc = "reshape";
7324         else
7325                 desc = "recovery";
7326
7327         /* we overload curr_resync somewhat here.
7328          * 0 == not engaged in resync at all
7329          * 2 == checking that there is no conflict with another sync
7330          * 1 == like 2, but have yielded to allow conflicting resync to
7331          *              commense
7332          * other == active in resync - this many blocks
7333          *
7334          * Before starting a resync we must have set curr_resync to
7335          * 2, and then checked that every "conflicting" array has curr_resync
7336          * less than ours.  When we find one that is the same or higher
7337          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
7338          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
7339          * This will mean we have to start checking from the beginning again.
7340          *
7341          */
7342
7343         do {
7344                 mddev->curr_resync = 2;
7345
7346         try_again:
7347                 if (kthread_should_stop())
7348                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7349
7350                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
7351                         goto skip;
7352                 for_each_mddev(mddev2, tmp) {
7353                         if (mddev2 == mddev)
7354                                 continue;
7355                         if (!mddev->parallel_resync
7356                         &&  mddev2->curr_resync
7357                         &&  match_mddev_units(mddev, mddev2)) {
7358                                 DEFINE_WAIT(wq);
7359                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
7360                                         /* arbitrarily yield */
7361                                         mddev->curr_resync = 1;
7362                                         wake_up(&resync_wait);
7363                                 }
7364                                 if (mddev > mddev2 && mddev->curr_resync == 1)
7365                                         /* no need to wait here, we can wait the next
7366                                          * time 'round when curr_resync == 2
7367                                          */
7368                                         continue;
7369                                 /* We need to wait 'interruptible' so as not to
7370                                  * contribute to the load average, and not to
7371                                  * be caught by 'softlockup'
7372                                  */
7373                                 prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
7374                                 if (!kthread_should_stop() &&
7375                                     mddev2->curr_resync >= mddev->curr_resync) {
7376                                         printk(KERN_INFO "md: delaying %s of %s"
7377                                                " until %s has finished (they"
7378                                                " share one or more physical units)\n",
7379                                                desc, mdname(mddev), mdname(mddev2));
7380                                         mddev_put(mddev2);
7381                                         if (signal_pending(current))
7382                                                 flush_signals(current);
7383                                         schedule();
7384                                         finish_wait(&resync_wait, &wq);
7385                                         goto try_again;
7386                                 }
7387                                 finish_wait(&resync_wait, &wq);
7388                         }
7389                 }
7390         } while (mddev->curr_resync < 2);
7391
7392         j = 0;
7393         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
7394                 /* resync follows the size requested by the personality,
7395                  * which defaults to physical size, but can be virtual size
7396                  */
7397                 max_sectors = mddev->resync_max_sectors;
7398                 mddev->resync_mismatches = 0;
7399                 /* we don't use the checkpoint if there's a bitmap */
7400                 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7401                         j = mddev->resync_min;
7402                 else if (!mddev->bitmap)
7403                         j = mddev->recovery_cp;
7404
7405         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
7406                 max_sectors = mddev->resync_max_sectors;
7407         else {
7408                 /* recovery follows the physical size of devices */
7409                 max_sectors = mddev->dev_sectors;
7410                 j = MaxSector;
7411                 rcu_read_lock();
7412                 rdev_for_each_rcu(rdev, mddev)
7413                         if (rdev->raid_disk >= 0 &&
7414                             !test_bit(Faulty, &rdev->flags) &&
7415                             !test_bit(In_sync, &rdev->flags) &&
7416                             rdev->recovery_offset < j)
7417                                 j = rdev->recovery_offset;
7418                 rcu_read_unlock();
7419         }
7420
7421         printk(KERN_INFO "md: %s of RAID array %s\n", desc, mdname(mddev));
7422         printk(KERN_INFO "md: minimum _guaranteed_  speed:"
7423                 " %d KB/sec/disk.\n", speed_min(mddev));
7424         printk(KERN_INFO "md: using maximum available idle IO bandwidth "
7425                "(but not more than %d KB/sec) for %s.\n",
7426                speed_max(mddev), desc);
7427
7428         is_mddev_idle(mddev, 1); /* this initializes IO event counters */
7429
7430         io_sectors = 0;
7431         for (m = 0; m < SYNC_MARKS; m++) {
7432                 mark[m] = jiffies;
7433                 mark_cnt[m] = io_sectors;
7434         }
7435         last_mark = 0;
7436         mddev->resync_mark = mark[last_mark];
7437         mddev->resync_mark_cnt = mark_cnt[last_mark];
7438
7439         /*
7440          * Tune reconstruction:
7441          */
7442         window = 32*(PAGE_SIZE/512);
7443         printk(KERN_INFO "md: using %dk window, over a total of %lluk.\n",
7444                 window/2, (unsigned long long)max_sectors/2);
7445
7446         atomic_set(&mddev->recovery_active, 0);
7447         last_check = 0;
7448
7449         if (j>2) {
7450                 printk(KERN_INFO
7451                        "md: resuming %s of %s from checkpoint.\n",
7452                        desc, mdname(mddev));
7453                 mddev->curr_resync = j;
7454         }
7455         mddev->curr_resync_completed = j;
7456
7457         blk_start_plug(&plug);
7458         while (j < max_sectors) {
7459                 sector_t sectors;
7460
7461                 skipped = 0;
7462
7463                 if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
7464                     ((mddev->curr_resync > mddev->curr_resync_completed &&
7465                       (mddev->curr_resync - mddev->curr_resync_completed)
7466                       > (max_sectors >> 4)) ||
7467                      (j - mddev->curr_resync_completed)*2
7468                      >= mddev->resync_max - mddev->curr_resync_completed
7469                             )) {
7470                         /* time to update curr_resync_completed */
7471                         wait_event(mddev->recovery_wait,
7472                                    atomic_read(&mddev->recovery_active) == 0);
7473                         mddev->curr_resync_completed = j;
7474                         set_bit(MD_CHANGE_CLEAN, &mddev->flags);
7475                         sysfs_notify(&mddev->kobj, NULL, "sync_completed");
7476                 }
7477
7478                 while (j >= mddev->resync_max && !kthread_should_stop()) {
7479                         /* As this condition is controlled by user-space,
7480                          * we can block indefinitely, so use '_interruptible'
7481                          * to avoid triggering warnings.
7482                          */
7483                         flush_signals(current); /* just in case */
7484                         wait_event_interruptible(mddev->recovery_wait,
7485                                                  mddev->resync_max > j
7486                                                  || kthread_should_stop());
7487                 }
7488
7489                 if (kthread_should_stop())
7490                         goto interrupted;
7491
7492                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
7493                                                   currspeed < speed_min(mddev));
7494                 if (sectors == 0) {
7495                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7496                         goto out;
7497                 }
7498
7499                 if (!skipped) { /* actual IO requested */
7500                         io_sectors += sectors;
7501                         atomic_add(sectors, &mddev->recovery_active);
7502                 }
7503
7504                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
7505                         break;
7506
7507                 j += sectors;
7508                 if (j>1) mddev->curr_resync = j;
7509                 mddev->curr_mark_cnt = io_sectors;
7510                 if (last_check == 0)
7511                         /* this is the earliest that rebuild will be
7512                          * visible in /proc/mdstat
7513                          */
7514                         md_new_event(mddev);
7515
7516                 if (last_check + window > io_sectors || j == max_sectors)
7517                         continue;
7518
7519                 last_check = io_sectors;
7520         repeat:
7521                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
7522                         /* step marks */
7523                         int next = (last_mark+1) % SYNC_MARKS;
7524
7525                         mddev->resync_mark = mark[next];
7526                         mddev->resync_mark_cnt = mark_cnt[next];
7527                         mark[next] = jiffies;
7528                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
7529                         last_mark = next;
7530                 }
7531
7532
7533                 if (kthread_should_stop())
7534                         goto interrupted;
7535
7536
7537                 /*
7538                  * this loop exits only if either when we are slower than
7539                  * the 'hard' speed limit, or the system was IO-idle for
7540                  * a jiffy.
7541                  * the system might be non-idle CPU-wise, but we only care
7542                  * about not overloading the IO subsystem. (things like an
7543                  * e2fsck being done on the RAID array should execute fast)
7544                  */
7545                 cond_resched();
7546
7547                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
7548                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
7549
7550                 if (currspeed > speed_min(mddev)) {
7551                         if ((currspeed > speed_max(mddev)) ||
7552                                         !is_mddev_idle(mddev, 0)) {
7553                                 msleep(500);
7554                                 goto repeat;
7555                         }
7556                 }
7557         }
7558         printk(KERN_INFO "md: %s: %s done.\n",mdname(mddev), desc);
7559         /*
7560          * this also signals 'finished resyncing' to md_stop
7561          */
7562  out:
7563         blk_finish_plug(&plug);
7564         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
7565
7566         /* tell personality that we are finished */
7567         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
7568
7569         if (!test_bit(MD_RECOVERY_CHECK, &mddev->recovery) &&
7570             mddev->curr_resync > 2) {
7571                 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
7572                         if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
7573                                 if (mddev->curr_resync >= mddev->recovery_cp) {
7574                                         printk(KERN_INFO
7575                                                "md: checkpointing %s of %s.\n",
7576                                                desc, mdname(mddev));
7577                                         mddev->recovery_cp =
7578                                                 mddev->curr_resync_completed;
7579                                 }
7580                         } else
7581                                 mddev->recovery_cp = MaxSector;
7582                 } else {
7583                         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
7584                                 mddev->curr_resync = MaxSector;
7585                         rcu_read_lock();
7586                         rdev_for_each_rcu(rdev, mddev)
7587                                 if (rdev->raid_disk >= 0 &&
7588                                     mddev->delta_disks >= 0 &&
7589                                     !test_bit(Faulty, &rdev->flags) &&
7590                                     !test_bit(In_sync, &rdev->flags) &&
7591                                     rdev->recovery_offset < mddev->curr_resync)
7592                                         rdev->recovery_offset = mddev->curr_resync;
7593                         rcu_read_unlock();
7594                 }
7595         }
7596  skip:
7597         set_bit(MD_CHANGE_DEVS, &mddev->flags);
7598
7599         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
7600                 /* We completed so min/max setting can be forgotten if used. */
7601                 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7602                         mddev->resync_min = 0;
7603                 mddev->resync_max = MaxSector;
7604         } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7605                 mddev->resync_min = mddev->curr_resync_completed;
7606         mddev->curr_resync = 0;
7607         wake_up(&resync_wait);
7608         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
7609         md_wakeup_thread(mddev->thread);
7610         return;
7611
7612  interrupted:
7613         /*
7614          * got a signal, exit.
7615          */
7616         printk(KERN_INFO
7617                "md: md_do_sync() got signal ... exiting\n");
7618         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7619         goto out;
7620
7621 }
7622 EXPORT_SYMBOL_GPL(md_do_sync);
7623
7624 static int remove_and_add_spares(struct mddev *mddev)
7625 {
7626         struct md_rdev *rdev;
7627         int spares = 0;
7628         int removed = 0;
7629
7630         mddev->curr_resync_completed = 0;
7631
7632         rdev_for_each(rdev, mddev)
7633                 if (rdev->raid_disk >= 0 &&
7634                     !test_bit(Blocked, &rdev->flags) &&
7635                     (test_bit(Faulty, &rdev->flags) ||
7636                      ! test_bit(In_sync, &rdev->flags)) &&
7637                     atomic_read(&rdev->nr_pending)==0) {
7638                         if (mddev->pers->hot_remove_disk(
7639                                     mddev, rdev) == 0) {
7640                                 sysfs_unlink_rdev(mddev, rdev);
7641                                 rdev->raid_disk = -1;
7642                                 removed++;
7643                         }
7644                 }
7645         if (removed)
7646                 sysfs_notify(&mddev->kobj, NULL,
7647                              "degraded");
7648
7649
7650         rdev_for_each(rdev, mddev) {
7651                 if (rdev->raid_disk >= 0 &&
7652                     !test_bit(In_sync, &rdev->flags) &&
7653                     !test_bit(Faulty, &rdev->flags))
7654                         spares++;
7655                 if (rdev->raid_disk < 0
7656                     && !test_bit(Faulty, &rdev->flags)) {
7657                         rdev->recovery_offset = 0;
7658                         if (mddev->pers->
7659                             hot_add_disk(mddev, rdev) == 0) {
7660                                 if (sysfs_link_rdev(mddev, rdev))
7661                                         /* failure here is OK */;
7662                                 spares++;
7663                                 md_new_event(mddev);
7664                                 set_bit(MD_CHANGE_DEVS, &mddev->flags);
7665                         }
7666                 }
7667         }
7668         return spares;
7669 }
7670
7671 static void reap_sync_thread(struct mddev *mddev)
7672 {
7673         struct md_rdev *rdev;
7674
7675         /* resync has finished, collect result */
7676         md_unregister_thread(&mddev->sync_thread);
7677         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
7678             !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
7679                 /* success...*/
7680                 /* activate any spares */
7681                 if (mddev->pers->spare_active(mddev))
7682                         sysfs_notify(&mddev->kobj, NULL,
7683                                      "degraded");
7684         }
7685         if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
7686             mddev->pers->finish_reshape)
7687                 mddev->pers->finish_reshape(mddev);
7688
7689         /* If array is no-longer degraded, then any saved_raid_disk
7690          * information must be scrapped.  Also if any device is now
7691          * In_sync we must scrape the saved_raid_disk for that device
7692          * do the superblock for an incrementally recovered device
7693          * written out.
7694          */
7695         rdev_for_each(rdev, mddev)
7696                 if (!mddev->degraded ||
7697                     test_bit(In_sync, &rdev->flags))
7698                         rdev->saved_raid_disk = -1;
7699
7700         md_update_sb(mddev, 1);
7701         clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7702         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7703         clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7704         clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
7705         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7706         /* flag recovery needed just to double check */
7707         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7708         sysfs_notify_dirent_safe(mddev->sysfs_action);
7709         md_new_event(mddev);
7710         if (mddev->event_work.func)
7711                 queue_work(md_misc_wq, &mddev->event_work);
7712 }
7713
7714 /*
7715  * This routine is regularly called by all per-raid-array threads to
7716  * deal with generic issues like resync and super-block update.
7717  * Raid personalities that don't have a thread (linear/raid0) do not
7718  * need this as they never do any recovery or update the superblock.
7719  *
7720  * It does not do any resync itself, but rather "forks" off other threads
7721  * to do that as needed.
7722  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
7723  * "->recovery" and create a thread at ->sync_thread.
7724  * When the thread finishes it sets MD_RECOVERY_DONE
7725  * and wakeups up this thread which will reap the thread and finish up.
7726  * This thread also removes any faulty devices (with nr_pending == 0).
7727  *
7728  * The overall approach is:
7729  *  1/ if the superblock needs updating, update it.
7730  *  2/ If a recovery thread is running, don't do anything else.
7731  *  3/ If recovery has finished, clean up, possibly marking spares active.
7732  *  4/ If there are any faulty devices, remove them.
7733  *  5/ If array is degraded, try to add spares devices
7734  *  6/ If array has spares or is not in-sync, start a resync thread.
7735  */
7736 void md_check_recovery(struct mddev *mddev)
7737 {
7738         if (mddev->suspended)
7739                 return;
7740
7741         if (mddev->bitmap)
7742                 bitmap_daemon_work(mddev);
7743
7744         if (signal_pending(current)) {
7745                 if (mddev->pers->sync_request && !mddev->external) {
7746                         printk(KERN_INFO "md: %s in immediate safe mode\n",
7747                                mdname(mddev));
7748                         mddev->safemode = 2;
7749                 }
7750                 flush_signals(current);
7751         }
7752
7753         if (mddev->ro && !test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
7754                 return;
7755         if ( ! (
7756                 (mddev->flags & ~ (1<<MD_CHANGE_PENDING)) ||
7757                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
7758                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
7759                 (mddev->external == 0 && mddev->safemode == 1) ||
7760                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
7761                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
7762                 ))
7763                 return;
7764
7765         if (mddev_trylock(mddev)) {
7766                 int spares = 0;
7767
7768                 if (mddev->ro) {
7769                         /* Only thing we do on a ro array is remove
7770                          * failed devices.
7771                          */
7772                         struct md_rdev *rdev;
7773                         rdev_for_each(rdev, mddev)
7774                                 if (rdev->raid_disk >= 0 &&
7775                                     !test_bit(Blocked, &rdev->flags) &&
7776                                     test_bit(Faulty, &rdev->flags) &&
7777                                     atomic_read(&rdev->nr_pending)==0) {
7778                                         if (mddev->pers->hot_remove_disk(
7779                                                     mddev, rdev) == 0) {
7780                                                 sysfs_unlink_rdev(mddev, rdev);
7781                                                 rdev->raid_disk = -1;
7782                                         }
7783                                 }
7784                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7785                         goto unlock;
7786                 }
7787
7788                 if (!mddev->external) {
7789                         int did_change = 0;
7790                         spin_lock_irq(&mddev->write_lock);
7791                         if (mddev->safemode &&
7792                             !atomic_read(&mddev->writes_pending) &&
7793                             !mddev->in_sync &&
7794                             mddev->recovery_cp == MaxSector) {
7795                                 mddev->in_sync = 1;
7796                                 did_change = 1;
7797                                 set_bit(MD_CHANGE_CLEAN, &mddev->flags);
7798                         }
7799                         if (mddev->safemode == 1)
7800                                 mddev->safemode = 0;
7801                         spin_unlock_irq(&mddev->write_lock);
7802                         if (did_change)
7803                                 sysfs_notify_dirent_safe(mddev->sysfs_state);
7804                 }
7805
7806                 if (mddev->flags)
7807                         md_update_sb(mddev, 0);
7808
7809                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
7810                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
7811                         /* resync/recovery still happening */
7812                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7813                         goto unlock;
7814                 }
7815                 if (mddev->sync_thread) {
7816                         reap_sync_thread(mddev);
7817                         goto unlock;
7818                 }
7819                 /* Set RUNNING before clearing NEEDED to avoid
7820                  * any transients in the value of "sync_action".
7821                  */
7822                 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7823                 /* Clear some bits that don't mean anything, but
7824                  * might be left set
7825                  */
7826                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
7827                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
7828
7829                 if (!test_and_clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
7830                     test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
7831                         goto unlock;
7832                 /* no recovery is running.
7833                  * remove any failed drives, then
7834                  * add spares if possible.
7835                  * Spare are also removed and re-added, to allow
7836                  * the personality to fail the re-add.
7837                  */
7838
7839                 if (mddev->reshape_position != MaxSector) {
7840                         if (mddev->pers->check_reshape == NULL ||
7841                             mddev->pers->check_reshape(mddev) != 0)
7842                                 /* Cannot proceed */
7843                                 goto unlock;
7844                         set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7845                         clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
7846                 } else if ((spares = remove_and_add_spares(mddev))) {
7847                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7848                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7849                         clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
7850                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
7851                 } else if (mddev->recovery_cp < MaxSector) {
7852                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7853                         clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
7854                 } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
7855                         /* nothing to be done ... */
7856                         goto unlock;
7857
7858                 if (mddev->pers->sync_request) {
7859                         if (spares) {
7860                                 /* We are adding a device or devices to an array
7861                                  * which has the bitmap stored on all devices.
7862                                  * So make sure all bitmap pages get written
7863                                  */
7864                                 bitmap_write_all(mddev->bitmap);
7865                         }
7866                         mddev->sync_thread = md_register_thread(md_do_sync,
7867                                                                 mddev,
7868                                                                 "resync");
7869                         if (!mddev->sync_thread) {
7870                                 printk(KERN_ERR "%s: could not start resync"
7871                                         " thread...\n",
7872                                         mdname(mddev));
7873                                 /* leave the spares where they are, it shouldn't hurt */
7874                                 clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7875                                 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7876                                 clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7877                                 clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
7878                                 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7879                         } else
7880                                 md_wakeup_thread(mddev->sync_thread);
7881                         sysfs_notify_dirent_safe(mddev->sysfs_action);
7882                         md_new_event(mddev);
7883                 }
7884         unlock:
7885                 if (!mddev->sync_thread) {
7886                         clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7887                         if (test_and_clear_bit(MD_RECOVERY_RECOVER,
7888                                                &mddev->recovery))
7889                                 if (mddev->sysfs_action)
7890                                         sysfs_notify_dirent_safe(mddev->sysfs_action);
7891                 }
7892                 mddev_unlock(mddev);
7893         }
7894 }
7895
7896 void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev)
7897 {
7898         sysfs_notify_dirent_safe(rdev->sysfs_state);
7899         wait_event_timeout(rdev->blocked_wait,
7900                            !test_bit(Blocked, &rdev->flags) &&
7901                            !test_bit(BlockedBadBlocks, &rdev->flags),
7902                            msecs_to_jiffies(5000));
7903         rdev_dec_pending(rdev, mddev);
7904 }
7905 EXPORT_SYMBOL(md_wait_for_blocked_rdev);
7906
7907 void md_finish_reshape(struct mddev *mddev)
7908 {
7909         /* called be personality module when reshape completes. */
7910         struct md_rdev *rdev;
7911
7912         rdev_for_each(rdev, mddev) {
7913                 if (rdev->data_offset > rdev->new_data_offset)
7914                         rdev->sectors += rdev->data_offset - rdev->new_data_offset;
7915                 else
7916                         rdev->sectors -= rdev->new_data_offset - rdev->data_offset;
7917                 rdev->data_offset = rdev->new_data_offset;
7918         }
7919 }
7920 EXPORT_SYMBOL(md_finish_reshape);
7921
7922 /* Bad block management.
7923  * We can record which blocks on each device are 'bad' and so just
7924  * fail those blocks, or that stripe, rather than the whole device.
7925  * Entries in the bad-block table are 64bits wide.  This comprises:
7926  * Length of bad-range, in sectors: 0-511 for lengths 1-512
7927  * Start of bad-range, sector offset, 54 bits (allows 8 exbibytes)
7928  *  A 'shift' can be set so that larger blocks are tracked and
7929  *  consequently larger devices can be covered.
7930  * 'Acknowledged' flag - 1 bit. - the most significant bit.
7931  *
7932  * Locking of the bad-block table uses a seqlock so md_is_badblock
7933  * might need to retry if it is very unlucky.
7934  * We will sometimes want to check for bad blocks in a bi_end_io function,
7935  * so we use the write_seqlock_irq variant.
7936  *
7937  * When looking for a bad block we specify a range and want to
7938  * know if any block in the range is bad.  So we binary-search
7939  * to the last range that starts at-or-before the given endpoint,
7940  * (or "before the sector after the target range")
7941  * then see if it ends after the given start.
7942  * We return
7943  *  0 if there are no known bad blocks in the range
7944  *  1 if there are known bad block which are all acknowledged
7945  * -1 if there are bad blocks which have not yet been acknowledged in metadata.
7946  * plus the start/length of the first bad section we overlap.
7947  */
7948 int md_is_badblock(struct badblocks *bb, sector_t s, int sectors,
7949                    sector_t *first_bad, int *bad_sectors)
7950 {
7951         int hi;
7952         int lo = 0;
7953         u64 *p = bb->page;
7954         int rv = 0;
7955         sector_t target = s + sectors;
7956         unsigned seq;
7957
7958         if (bb->shift > 0) {
7959                 /* round the start down, and the end up */
7960                 s >>= bb->shift;
7961                 target += (1<<bb->shift) - 1;
7962                 target >>= bb->shift;
7963                 sectors = target - s;
7964         }
7965         /* 'target' is now the first block after the bad range */
7966
7967 retry:
7968         seq = read_seqbegin(&bb->lock);
7969
7970         hi = bb->count;
7971
7972         /* Binary search between lo and hi for 'target'
7973          * i.e. for the last range that starts before 'target'
7974          */
7975         /* INVARIANT: ranges before 'lo' and at-or-after 'hi'
7976          * are known not to be the last range before target.
7977          * VARIANT: hi-lo is the number of possible
7978          * ranges, and decreases until it reaches 1
7979          */
7980         while (hi - lo > 1) {
7981                 int mid = (lo + hi) / 2;
7982                 sector_t a = BB_OFFSET(p[mid]);
7983                 if (a < target)
7984                         /* This could still be the one, earlier ranges
7985                          * could not. */
7986                         lo = mid;
7987                 else
7988                         /* This and later ranges are definitely out. */
7989                         hi = mid;
7990         }
7991         /* 'lo' might be the last that started before target, but 'hi' isn't */
7992         if (hi > lo) {
7993                 /* need to check all range that end after 's' to see if
7994                  * any are unacknowledged.
7995                  */
7996                 while (lo >= 0 &&
7997                        BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > s) {
7998                         if (BB_OFFSET(p[lo]) < target) {
7999                                 /* starts before the end, and finishes after
8000                                  * the start, so they must overlap
8001                                  */
8002                                 if (rv != -1 && BB_ACK(p[lo]))
8003                                         rv = 1;
8004                                 else
8005                                         rv = -1;
8006                                 *first_bad = BB_OFFSET(p[lo]);
8007                                 *bad_sectors = BB_LEN(p[lo]);
8008                         }
8009                         lo--;
8010                 }
8011         }
8012
8013         if (read_seqretry(&bb->lock, seq))
8014                 goto retry;
8015
8016         return rv;
8017 }
8018 EXPORT_SYMBOL_GPL(md_is_badblock);
8019
8020 /*
8021  * Add a range of bad blocks to the table.
8022  * This might extend the table, or might contract it
8023  * if two adjacent ranges can be merged.
8024  * We binary-search to find the 'insertion' point, then
8025  * decide how best to handle it.
8026  */
8027 static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors,
8028                             int acknowledged)
8029 {
8030         u64 *p;
8031         int lo, hi;
8032         int rv = 1;
8033
8034         if (bb->shift < 0)
8035                 /* badblocks are disabled */
8036                 return 0;
8037
8038         if (bb->shift) {
8039                 /* round the start down, and the end up */
8040                 sector_t next = s + sectors;
8041                 s >>= bb->shift;
8042                 next += (1<<bb->shift) - 1;
8043                 next >>= bb->shift;
8044                 sectors = next - s;
8045         }
8046
8047         write_seqlock_irq(&bb->lock);
8048
8049         p = bb->page;
8050         lo = 0;
8051         hi = bb->count;
8052         /* Find the last range that starts at-or-before 's' */
8053         while (hi - lo > 1) {
8054                 int mid = (lo + hi) / 2;
8055                 sector_t a = BB_OFFSET(p[mid]);
8056                 if (a <= s)
8057                         lo = mid;
8058                 else
8059                         hi = mid;
8060         }
8061         if (hi > lo && BB_OFFSET(p[lo]) > s)
8062                 hi = lo;
8063
8064         if (hi > lo) {
8065                 /* we found a range that might merge with the start
8066                  * of our new range
8067                  */
8068                 sector_t a = BB_OFFSET(p[lo]);
8069                 sector_t e = a + BB_LEN(p[lo]);
8070                 int ack = BB_ACK(p[lo]);
8071                 if (e >= s) {
8072                         /* Yes, we can merge with a previous range */
8073                         if (s == a && s + sectors >= e)
8074                                 /* new range covers old */
8075                                 ack = acknowledged;
8076                         else
8077                                 ack = ack && acknowledged;
8078
8079                         if (e < s + sectors)
8080                                 e = s + sectors;
8081                         if (e - a <= BB_MAX_LEN) {
8082                                 p[lo] = BB_MAKE(a, e-a, ack);
8083                                 s = e;
8084                         } else {
8085                                 /* does not all fit in one range,
8086                                  * make p[lo] maximal
8087                                  */
8088                                 if (BB_LEN(p[lo]) != BB_MAX_LEN)
8089                                         p[lo] = BB_MAKE(a, BB_MAX_LEN, ack);
8090                                 s = a + BB_MAX_LEN;
8091                         }
8092                         sectors = e - s;
8093                 }
8094         }
8095         if (sectors && hi < bb->count) {
8096                 /* 'hi' points to the first range that starts after 's'.
8097                  * Maybe we can merge with the start of that range */
8098                 sector_t a = BB_OFFSET(p[hi]);
8099                 sector_t e = a + BB_LEN(p[hi]);
8100                 int ack = BB_ACK(p[hi]);
8101                 if (a <= s + sectors) {
8102                         /* merging is possible */
8103                         if (e <= s + sectors) {
8104                                 /* full overlap */
8105                                 e = s + sectors;
8106                                 ack = acknowledged;
8107                         } else
8108                                 ack = ack && acknowledged;
8109
8110                         a = s;
8111                         if (e - a <= BB_MAX_LEN) {
8112                                 p[hi] = BB_MAKE(a, e-a, ack);
8113                                 s = e;
8114                         } else {
8115                                 p[hi] = BB_MAKE(a, BB_MAX_LEN, ack);
8116                                 s = a + BB_MAX_LEN;
8117                         }
8118                         sectors = e - s;
8119                         lo = hi;
8120                         hi++;
8121                 }
8122         }
8123         if (sectors == 0 && hi < bb->count) {
8124                 /* we might be able to combine lo and hi */
8125                 /* Note: 's' is at the end of 'lo' */
8126                 sector_t a = BB_OFFSET(p[hi]);
8127                 int lolen = BB_LEN(p[lo]);
8128                 int hilen = BB_LEN(p[hi]);
8129                 int newlen = lolen + hilen - (s - a);
8130                 if (s >= a && newlen < BB_MAX_LEN) {
8131                         /* yes, we can combine them */
8132                         int ack = BB_ACK(p[lo]) && BB_ACK(p[hi]);
8133                         p[lo] = BB_MAKE(BB_OFFSET(p[lo]), newlen, ack);
8134                         memmove(p + hi, p + hi + 1,
8135                                 (bb->count - hi - 1) * 8);
8136                         bb->count--;
8137                 }
8138         }
8139         while (sectors) {
8140                 /* didn't merge (it all).
8141                  * Need to add a range just before 'hi' */
8142                 if (bb->count >= MD_MAX_BADBLOCKS) {
8143                         /* No room for more */
8144                         rv = 0;
8145                         break;
8146                 } else {
8147                         int this_sectors = sectors;
8148                         memmove(p + hi + 1, p + hi,
8149                                 (bb->count - hi) * 8);
8150                         bb->count++;
8151
8152                         if (this_sectors > BB_MAX_LEN)
8153                                 this_sectors = BB_MAX_LEN;
8154                         p[hi] = BB_MAKE(s, this_sectors, acknowledged);
8155                         sectors -= this_sectors;
8156                         s += this_sectors;
8157                 }
8158         }
8159
8160         bb->changed = 1;
8161         if (!acknowledged)
8162                 bb->unacked_exist = 1;
8163         write_sequnlock_irq(&bb->lock);
8164
8165         return rv;
8166 }
8167
8168 int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
8169                        int is_new)
8170 {
8171         int rv;
8172         if (is_new)
8173                 s += rdev->new_data_offset;
8174         else
8175                 s += rdev->data_offset;
8176         rv = md_set_badblocks(&rdev->badblocks,
8177                               s, sectors, 0);
8178         if (rv) {
8179                 /* Make sure they get written out promptly */
8180                 sysfs_notify_dirent_safe(rdev->sysfs_state);
8181                 set_bit(MD_CHANGE_CLEAN, &rdev->mddev->flags);
8182                 md_wakeup_thread(rdev->mddev->thread);
8183         }
8184         return rv;
8185 }
8186 EXPORT_SYMBOL_GPL(rdev_set_badblocks);
8187
8188 /*
8189  * Remove a range of bad blocks from the table.
8190  * This may involve extending the table if we spilt a region,
8191  * but it must not fail.  So if the table becomes full, we just
8192  * drop the remove request.
8193  */
8194 static int md_clear_badblocks(struct badblocks *bb, sector_t s, int sectors)
8195 {
8196         u64 *p;
8197         int lo, hi;
8198         sector_t target = s + sectors;
8199         int rv = 0;
8200
8201         if (bb->shift > 0) {
8202                 /* When clearing we round the start up and the end down.
8203                  * This should not matter as the shift should align with
8204                  * the block size and no rounding should ever be needed.
8205                  * However it is better the think a block is bad when it
8206                  * isn't than to think a block is not bad when it is.
8207                  */
8208                 s += (1<<bb->shift) - 1;
8209                 s >>= bb->shift;
8210                 target >>= bb->shift;
8211                 sectors = target - s;
8212         }
8213
8214         write_seqlock_irq(&bb->lock);
8215
8216         p = bb->page;
8217         lo = 0;
8218         hi = bb->count;
8219         /* Find the last range that starts before 'target' */
8220         while (hi - lo > 1) {
8221                 int mid = (lo + hi) / 2;
8222                 sector_t a = BB_OFFSET(p[mid]);
8223                 if (a < target)
8224                         lo = mid;
8225                 else
8226                         hi = mid;
8227         }
8228         if (hi > lo) {
8229                 /* p[lo] is the last range that could overlap the
8230                  * current range.  Earlier ranges could also overlap,
8231                  * but only this one can overlap the end of the range.
8232                  */
8233                 if (BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > target) {
8234                         /* Partial overlap, leave the tail of this range */
8235                         int ack = BB_ACK(p[lo]);
8236                         sector_t a = BB_OFFSET(p[lo]);
8237                         sector_t end = a + BB_LEN(p[lo]);
8238
8239                         if (a < s) {
8240                                 /* we need to split this range */
8241                                 if (bb->count >= MD_MAX_BADBLOCKS) {
8242                                         rv = 0;
8243                                         goto out;
8244                                 }
8245                                 memmove(p+lo+1, p+lo, (bb->count - lo) * 8);
8246                                 bb->count++;
8247                                 p[lo] = BB_MAKE(a, s-a, ack);
8248                                 lo++;
8249                         }
8250                         p[lo] = BB_MAKE(target, end - target, ack);
8251                         /* there is no longer an overlap */
8252                         hi = lo;
8253                         lo--;
8254                 }
8255                 while (lo >= 0 &&
8256                        BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > s) {
8257                         /* This range does overlap */
8258                         if (BB_OFFSET(p[lo]) < s) {
8259                                 /* Keep the early parts of this range. */
8260                                 int ack = BB_ACK(p[lo]);
8261                                 sector_t start = BB_OFFSET(p[lo]);
8262                                 p[lo] = BB_MAKE(start, s - start, ack);
8263                                 /* now low doesn't overlap, so.. */
8264                                 break;
8265                         }
8266                         lo--;
8267                 }
8268                 /* 'lo' is strictly before, 'hi' is strictly after,
8269                  * anything between needs to be discarded
8270                  */
8271                 if (hi - lo > 1) {
8272                         memmove(p+lo+1, p+hi, (bb->count - hi) * 8);
8273                         bb->count -= (hi - lo - 1);
8274                 }
8275         }
8276
8277         bb->changed = 1;
8278 out:
8279         write_sequnlock_irq(&bb->lock);
8280         return rv;
8281 }
8282
8283 int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
8284                          int is_new)
8285 {
8286         if (is_new)
8287                 s += rdev->new_data_offset;
8288         else
8289                 s += rdev->data_offset;
8290         return md_clear_badblocks(&rdev->badblocks,
8291                                   s, sectors);
8292 }
8293 EXPORT_SYMBOL_GPL(rdev_clear_badblocks);
8294
8295 /*
8296  * Acknowledge all bad blocks in a list.
8297  * This only succeeds if ->changed is clear.  It is used by
8298  * in-kernel metadata updates
8299  */
8300 void md_ack_all_badblocks(struct badblocks *bb)
8301 {
8302         if (bb->page == NULL || bb->changed)
8303                 /* no point even trying */
8304                 return;
8305         write_seqlock_irq(&bb->lock);
8306
8307         if (bb->changed == 0 && bb->unacked_exist) {
8308                 u64 *p = bb->page;
8309                 int i;
8310                 for (i = 0; i < bb->count ; i++) {
8311                         if (!BB_ACK(p[i])) {
8312                                 sector_t start = BB_OFFSET(p[i]);
8313                                 int len = BB_LEN(p[i]);
8314                                 p[i] = BB_MAKE(start, len, 1);
8315                         }
8316                 }
8317                 bb->unacked_exist = 0;
8318         }
8319         write_sequnlock_irq(&bb->lock);
8320 }
8321 EXPORT_SYMBOL_GPL(md_ack_all_badblocks);
8322
8323 /* sysfs access to bad-blocks list.
8324  * We present two files.
8325  * 'bad-blocks' lists sector numbers and lengths of ranges that
8326  *    are recorded as bad.  The list is truncated to fit within
8327  *    the one-page limit of sysfs.
8328  *    Writing "sector length" to this file adds an acknowledged
8329  *    bad block list.
8330  * 'unacknowledged-bad-blocks' lists bad blocks that have not yet
8331  *    been acknowledged.  Writing to this file adds bad blocks
8332  *    without acknowledging them.  This is largely for testing.
8333  */
8334
8335 static ssize_t
8336 badblocks_show(struct badblocks *bb, char *page, int unack)
8337 {
8338         size_t len;
8339         int i;
8340         u64 *p = bb->page;
8341         unsigned seq;
8342
8343         if (bb->shift < 0)
8344                 return 0;
8345
8346 retry:
8347         seq = read_seqbegin(&bb->lock);
8348
8349         len = 0;
8350         i = 0;
8351
8352         while (len < PAGE_SIZE && i < bb->count) {
8353                 sector_t s = BB_OFFSET(p[i]);
8354                 unsigned int length = BB_LEN(p[i]);
8355                 int ack = BB_ACK(p[i]);
8356                 i++;
8357
8358                 if (unack && ack)
8359                         continue;
8360
8361                 len += snprintf(page+len, PAGE_SIZE-len, "%llu %u\n",
8362                                 (unsigned long long)s << bb->shift,
8363                                 length << bb->shift);
8364         }
8365         if (unack && len == 0)
8366                 bb->unacked_exist = 0;
8367
8368         if (read_seqretry(&bb->lock, seq))
8369                 goto retry;
8370
8371         return len;
8372 }
8373
8374 #define DO_DEBUG 1
8375
8376 static ssize_t
8377 badblocks_store(struct badblocks *bb, const char *page, size_t len, int unack)
8378 {
8379         unsigned long long sector;
8380         int length;
8381         char newline;
8382 #ifdef DO_DEBUG
8383         /* Allow clearing via sysfs *only* for testing/debugging.
8384          * Normally only a successful write may clear a badblock
8385          */
8386         int clear = 0;
8387         if (page[0] == '-') {
8388                 clear = 1;
8389                 page++;
8390         }
8391 #endif /* DO_DEBUG */
8392
8393         switch (sscanf(page, "%llu %d%c", &sector, &length, &newline)) {
8394         case 3:
8395                 if (newline != '\n')
8396                         return -EINVAL;
8397         case 2:
8398                 if (length <= 0)
8399                         return -EINVAL;
8400                 break;
8401         default:
8402                 return -EINVAL;
8403         }
8404
8405 #ifdef DO_DEBUG
8406         if (clear) {
8407                 md_clear_badblocks(bb, sector, length);
8408                 return len;
8409         }
8410 #endif /* DO_DEBUG */
8411         if (md_set_badblocks(bb, sector, length, !unack))
8412                 return len;
8413         else
8414                 return -ENOSPC;
8415 }
8416
8417 static int md_notify_reboot(struct notifier_block *this,
8418                             unsigned long code, void *x)
8419 {
8420         struct list_head *tmp;
8421         struct mddev *mddev;
8422         int need_delay = 0;
8423
8424         for_each_mddev(mddev, tmp) {
8425                 if (mddev_trylock(mddev)) {
8426                         if (mddev->pers)
8427                                 __md_stop_writes(mddev);
8428                         mddev->safemode = 2;
8429                         mddev_unlock(mddev);
8430                 }
8431                 need_delay = 1;
8432         }
8433         /*
8434          * certain more exotic SCSI devices are known to be
8435          * volatile wrt too early system reboots. While the
8436          * right place to handle this issue is the given
8437          * driver, we do want to have a safe RAID driver ...
8438          */
8439         if (need_delay)
8440                 mdelay(1000*1);
8441
8442         return NOTIFY_DONE;
8443 }
8444
8445 static struct notifier_block md_notifier = {
8446         .notifier_call  = md_notify_reboot,
8447         .next           = NULL,
8448         .priority       = INT_MAX, /* before any real devices */
8449 };
8450
8451 static void md_geninit(void)
8452 {
8453         pr_debug("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
8454
8455         proc_create("mdstat", S_IRUGO, NULL, &md_seq_fops);
8456 }
8457
8458 static int __init md_init(void)
8459 {
8460         int ret = -ENOMEM;
8461
8462         md_wq = alloc_workqueue("md", WQ_MEM_RECLAIM, 0);
8463         if (!md_wq)
8464                 goto err_wq;
8465
8466         md_misc_wq = alloc_workqueue("md_misc", 0, 0);
8467         if (!md_misc_wq)
8468                 goto err_misc_wq;
8469
8470         if ((ret = register_blkdev(MD_MAJOR, "md")) < 0)
8471                 goto err_md;
8472
8473         if ((ret = register_blkdev(0, "mdp")) < 0)
8474                 goto err_mdp;
8475         mdp_major = ret;
8476
8477         blk_register_region(MKDEV(MD_MAJOR, 0), 1UL<<MINORBITS, THIS_MODULE,
8478                             md_probe, NULL, NULL);
8479         blk_register_region(MKDEV(mdp_major, 0), 1UL<<MINORBITS, THIS_MODULE,
8480                             md_probe, NULL, NULL);
8481
8482         register_reboot_notifier(&md_notifier);
8483         raid_table_header = register_sysctl_table(raid_root_table);
8484
8485         md_geninit();
8486         return 0;
8487
8488 err_mdp:
8489         unregister_blkdev(MD_MAJOR, "md");
8490 err_md:
8491         destroy_workqueue(md_misc_wq);
8492 err_misc_wq:
8493         destroy_workqueue(md_wq);
8494 err_wq:
8495         return ret;
8496 }
8497
8498 #ifndef MODULE
8499
8500 /*
8501  * Searches all registered partitions for autorun RAID arrays
8502  * at boot time.
8503  */
8504
8505 static LIST_HEAD(all_detected_devices);
8506 struct detected_devices_node {
8507         struct list_head list;
8508         dev_t dev;
8509 };
8510
8511 void md_autodetect_dev(dev_t dev)
8512 {
8513         struct detected_devices_node *node_detected_dev;
8514
8515         node_detected_dev = kzalloc(sizeof(*node_detected_dev), GFP_KERNEL);
8516         if (node_detected_dev) {
8517                 node_detected_dev->dev = dev;
8518                 list_add_tail(&node_detected_dev->list, &all_detected_devices);
8519         } else {
8520                 printk(KERN_CRIT "md: md_autodetect_dev: kzalloc failed"
8521                         ", skipping dev(%d,%d)\n", MAJOR(dev), MINOR(dev));
8522         }
8523 }
8524
8525
8526 static void autostart_arrays(int part)
8527 {
8528         struct md_rdev *rdev;
8529         struct detected_devices_node *node_detected_dev;
8530         dev_t dev;
8531         int i_scanned, i_passed;
8532
8533         i_scanned = 0;
8534         i_passed = 0;
8535
8536         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
8537
8538         while (!list_empty(&all_detected_devices) && i_scanned < INT_MAX) {
8539                 i_scanned++;
8540                 node_detected_dev = list_entry(all_detected_devices.next,
8541                                         struct detected_devices_node, list);
8542                 list_del(&node_detected_dev->list);
8543                 dev = node_detected_dev->dev;
8544                 kfree(node_detected_dev);
8545                 rdev = md_import_device(dev,0, 90);
8546                 if (IS_ERR(rdev))
8547                         continue;
8548
8549                 if (test_bit(Faulty, &rdev->flags)) {
8550                         MD_BUG();
8551                         continue;
8552                 }
8553                 set_bit(AutoDetected, &rdev->flags);
8554                 list_add(&rdev->same_set, &pending_raid_disks);
8555                 i_passed++;
8556         }
8557
8558         printk(KERN_INFO "md: Scanned %d and added %d devices.\n",
8559                                                 i_scanned, i_passed);
8560
8561         autorun_devices(part);
8562 }
8563
8564 #endif /* !MODULE */
8565
8566 static __exit void md_exit(void)
8567 {
8568         struct mddev *mddev;
8569         struct list_head *tmp;
8570
8571         blk_unregister_region(MKDEV(MD_MAJOR,0), 1U << MINORBITS);
8572         blk_unregister_region(MKDEV(mdp_major,0), 1U << MINORBITS);
8573
8574         unregister_blkdev(MD_MAJOR,"md");
8575         unregister_blkdev(mdp_major, "mdp");
8576         unregister_reboot_notifier(&md_notifier);
8577         unregister_sysctl_table(raid_table_header);
8578         remove_proc_entry("mdstat", NULL);
8579         for_each_mddev(mddev, tmp) {
8580                 export_array(mddev);
8581                 mddev->hold_active = 0;
8582         }
8583         destroy_workqueue(md_misc_wq);
8584         destroy_workqueue(md_wq);
8585 }
8586
8587 subsys_initcall(md_init);
8588 module_exit(md_exit)
8589
8590 static int get_ro(char *buffer, struct kernel_param *kp)
8591 {
8592         return sprintf(buffer, "%d", start_readonly);
8593 }
8594 static int set_ro(const char *val, struct kernel_param *kp)
8595 {
8596         char *e;
8597         int num = simple_strtoul(val, &e, 10);
8598         if (*val && (*e == '\0' || *e == '\n')) {
8599                 start_readonly = num;
8600                 return 0;
8601         }
8602         return -EINVAL;
8603 }
8604
8605 module_param_call(start_ro, set_ro, get_ro, NULL, S_IRUSR|S_IWUSR);
8606 module_param(start_dirty_degraded, int, S_IRUGO|S_IWUSR);
8607
8608 module_param_call(new_array, add_named_array, NULL, NULL, S_IWUSR);
8609
8610 EXPORT_SYMBOL(register_md_personality);
8611 EXPORT_SYMBOL(unregister_md_personality);
8612 EXPORT_SYMBOL(md_error);
8613 EXPORT_SYMBOL(md_done_sync);
8614 EXPORT_SYMBOL(md_write_start);
8615 EXPORT_SYMBOL(md_write_end);
8616 EXPORT_SYMBOL(md_register_thread);
8617 EXPORT_SYMBOL(md_unregister_thread);
8618 EXPORT_SYMBOL(md_wakeup_thread);
8619 EXPORT_SYMBOL(md_check_recovery);
8620 MODULE_LICENSE("GPL");
8621 MODULE_DESCRIPTION("MD RAID framework");
8622 MODULE_ALIAS("md");
8623 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);