fs/gfs2/super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License v.2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/crc32.h>
  16 #include <linux/gfs2_ondisk.h>
  17 #include <linux/bio.h>
  18
  19 #include "gfs2.h"
  20 #include "lm_interface.h"
  21 #include "incore.h"
  22 #include "bmap.h"
  23 #include "dir.h"
  24 #include "format.h"
  25 #include "glock.h"
  26 #include "glops.h"
  27 #include "inode.h"
  28 #include "log.h"
  29 #include "meta_io.h"
  30 #include "quota.h"
  31 #include "recovery.h"
  32 #include "rgrp.h"
  33 #include "super.h"
  34 #include "trans.h"
  35 #include "util.h"
  36
  37 /**
  38  * gfs2_tune_init - Fill a gfs2_tune structure with default values
  39  * @gt: tune
  40  *
  41  */
  42
  43 void gfs2_tune_init(struct gfs2_tune *gt)
  44 {
  45         spin_lock_init(&gt->gt_spin);
  46
  47         gt->gt_ilimit = 100;
  48         gt->gt_ilimit_tries = 3;
  49         gt->gt_ilimit_min = 1;
  50         gt->gt_demote_secs = 300;
  51         gt->gt_incore_log_blocks = 1024;
  52         gt->gt_log_flush_secs = 60;
  53         gt->gt_jindex_refresh_secs = 60;
  54         gt->gt_scand_secs = 15;
  55         gt->gt_recoverd_secs = 60;
  56         gt->gt_logd_secs = 1;
  57         gt->gt_quotad_secs = 5;
  58         gt->gt_quota_simul_sync = 64;
  59         gt->gt_quota_warn_period = 10;
  60         gt->gt_quota_scale_num = 1;
  61         gt->gt_quota_scale_den = 1;
  62         gt->gt_quota_cache_secs = 300;
  63         gt->gt_quota_quantum = 60;
  64         gt->gt_atime_quantum = 3600;
  65         gt->gt_new_files_jdata = 0;
  66         gt->gt_new_files_directio = 0;
  67         gt->gt_max_atomic_write = 4 << 20;
  68         gt->gt_max_readahead = 1 << 18;
  69         gt->gt_lockdump_size = 131072;
  70         gt->gt_stall_secs = 600;
  71         gt->gt_complain_secs = 10;
  72         gt->gt_reclaim_limit = 5000;
  73         gt->gt_entries_per_readdir = 32;
  74         gt->gt_prefetch_secs = 10;
  75         gt->gt_greedy_default = HZ / 10;
  76         gt->gt_greedy_quantum = HZ / 40;
  77         gt->gt_greedy_max = HZ / 4;
  78         gt->gt_statfs_quantum = 30;
  79         gt->gt_statfs_slow = 0;
  80 }
  81
  82 /**
  83  * gfs2_check_sb - Check superblock
  84  * @sdp: the filesystem
  85  * @sb: The superblock
  86  * @silent: Don't print a message if the check fails
  87  *
  88  * Checks the version code of the FS is one that we understand how to
  89  * read and that the sizes of the various on-disk structures have not
  90  * changed.
  91  */
  92
  93 int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb *sb, int silent)
  94 {
  95         unsigned int x;
  96
  97         if (sb->sb_header.mh_magic != GFS2_MAGIC ||
  98             sb->sb_header.mh_type != GFS2_METATYPE_SB) {
  99                 if (!silent)
 100                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
 101                 return -EINVAL;
 102         }
 103
 104         /*  If format numbers match exactly, we're done.  */
 105
 106         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 107             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 108                 return 0;
 109
 110         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
 111                 for (x = 0; gfs2_old_fs_formats[x]; x++)
 112                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
 113                                 break;
 114
 115                 if (!gfs2_old_fs_formats[x]) {
 116                         printk(KERN_WARNING
 117                                "GFS2: code version (%u, %u) is incompatible "
 118                                "with ondisk format (%u, %u)\n",
 119                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 120                                sb->sb_fs_format, sb->sb_multihost_format);
 121                         printk(KERN_WARNING
 122                                "GFS2: I don't know how to upgrade this FS\n");
 123                         return -EINVAL;
 124                 }
 125         }
 126
 127         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
 128                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
 129                         if (gfs2_old_multihost_formats[x] ==
 130                             sb->sb_multihost_format)
 131                                 break;
 132
 133                 if (!gfs2_old_multihost_formats[x]) {
 134                         printk(KERN_WARNING
 135                                "GFS2: code version (%u, %u) is incompatible "
 136                                "with ondisk format (%u, %u)\n",
 137                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 138                                sb->sb_fs_format, sb->sb_multihost_format);
 139                         printk(KERN_WARNING
 140                                "GFS2: I don't know how to upgrade this FS\n");
 141                         return -EINVAL;
 142                 }
 143         }
 144
 145         if (!sdp->sd_args.ar_upgrade) {
 146                 printk(KERN_WARNING
 147                        "GFS2: code version (%u, %u) is incompatible "
 148                        "with ondisk format (%u, %u)\n",
 149                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 150                        sb->sb_fs_format, sb->sb_multihost_format);
 151                 printk(KERN_INFO
 152                        "GFS2: Use the \"upgrade\" mount option to upgrade "
 153                        "the FS\n");
 154                 printk(KERN_INFO "GFS2: See the manual for more details\n");
 155                 return -EINVAL;
 156         }
 157
 158         return 0;
 159 }
 160
 161
 162 static int end_bio_io_page(struct bio *bio, unsigned int bytes_done, int error)
 163 {
 164         struct page *page = bio->bi_private;
 165         if (bio->bi_size)
 166                 return 1;
 167
 168         if (!error)
 169                 SetPageUptodate(page);
 170         unlock_page(page);
 171         return 0;
 172 }
 173
 174 static struct page *gfs2_read_super(struct super_block *sb, sector_t sector)
 175 {
 176         struct page *page;
 177         struct bio *bio;
 178
 179         page = alloc_page(GFP_KERNEL);
 180         if (unlikely(!page))
 181                 return NULL;
 182
 183         ClearPageUptodate(page);
 184         ClearPageDirty(page);
 185         lock_page(page);
 186
 187         bio = bio_alloc(GFP_KERNEL, 1);
 188         if (unlikely(!bio)) {
 189                 __free_page(page);
 190                 return NULL;
 191         }
 192
 193         bio->bi_sector = sector;
 194         bio->bi_bdev = sb->s_bdev;
 195         bio_add_page(bio, page, PAGE_SIZE, 0);
 196
 197         bio->bi_end_io = end_bio_io_page;
 198         bio->bi_private = page;
 199         submit_bio(READ | BIO_RW_SYNC, bio);
 200         wait_on_page_locked(page);
 201         bio_put(bio);
 202         if (!PageUptodate(page)) {
 203                 __free_page(page);
 204                 return NULL;
 205         }
 206         return page;
 207 }
 208
 209 /**
 210  * gfs2_read_sb - Read super block
 211  * @sdp: The GFS2 superblock
 212  * @gl: the glock for the superblock (assumed to be held)
 213  * @silent: Don't print message if mount fails
 214  *
 215  */
 216
 217 int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
 218 {
 219         uint32_t hash_blocks, ind_blocks, leaf_blocks;
 220         uint32_t tmp_blocks;
 221         unsigned int x;
 222         int error;
 223         struct page *page;
 224         char *sb;
 225
 226         page = gfs2_read_super(sdp->sd_vfs, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
 227         if (!page) {
 228                 if (!silent)
 229                         fs_err(sdp, "can't read superblock\n");
 230                 return -EIO;
 231         }
 232         sb = kmap(page);
 233         gfs2_sb_in(&sdp->sd_sb, sb);
 234         kunmap(page);
 235         __free_page(page);
 236
 237         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
 238         if (error)
 239                 return error;
 240
 241         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 242                                GFS2_BASIC_BLOCK_SHIFT;
 243         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
 244         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 245                           sizeof(struct gfs2_dinode)) / sizeof(uint64_t);
 246         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 247                           sizeof(struct gfs2_meta_header)) / sizeof(uint64_t);
 248         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 249         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 250         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 251         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(uint64_t);
 252         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 253                                 sizeof(struct gfs2_meta_header)) /
 254                                 sizeof(struct gfs2_quota_change);
 255
 256         /* Compute maximum reservation required to add a entry to a directory */
 257
 258         hash_blocks = DIV_ROUND_UP(sizeof(uint64_t) * (1 << GFS2_DIR_MAX_DEPTH),
 259                              sdp->sd_jbsize);
 260
 261         ind_blocks = 0;
 262         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 263                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 264                 ind_blocks += tmp_blocks;
 265         }
 266
 267         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 268
 269         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 270
 271         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 272                                 sizeof(struct gfs2_dinode);
 273         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 274         for (x = 2;; x++) {
 275                 uint64_t space, d;
 276                 uint32_t m;
 277
 278                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 279                 d = space;
 280                 m = do_div(d, sdp->sd_inptrs);
 281
 282                 if (d != sdp->sd_heightsize[x - 1] || m)
 283                         break;
 284                 sdp->sd_heightsize[x] = space;
 285         }
 286         sdp->sd_max_height = x;
 287         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 288
 289         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 290                                  sizeof(struct gfs2_dinode);
 291         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 292         for (x = 2;; x++) {
 293                 uint64_t space, d;
 294                 uint32_t m;
 295
 296                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 297                 d = space;
 298                 m = do_div(d, sdp->sd_inptrs);
 299
 300                 if (d != sdp->sd_jheightsize[x - 1] || m)
 301                         break;
 302                 sdp->sd_jheightsize[x] = space;
 303         }
 304         sdp->sd_max_jheight = x;
 305         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 306
 307         return 0;
 308 }
 309
 310 /**
 311  * gfs2_jindex_hold - Grab a lock on the jindex
 312  * @sdp: The GFS2 superblock
 313  * @ji_gh: the holder for the jindex glock
 314  *
 315  * This is very similar to the gfs2_rindex_hold() function, except that
 316  * in general we hold the jindex lock for longer periods of time and
 317  * we grab it far less frequently (in general) then the rgrp lock.
 318  *
 319  * Returns: errno
 320  */
 321
 322 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 323 {
 324         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 325         struct qstr name;
 326         char buf[20];
 327         struct gfs2_jdesc *jd;
 328         int error;
 329
 330         name.name = buf;
 331
 332         mutex_lock(&sdp->sd_jindex_mutex);
 333
 334         for (;;) {
 335                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
 336                                            GL_LOCAL_EXCL, ji_gh);
 337                 if (error)
 338                         break;
 339
 340                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 341                 name.hash = gfs2_disk_hash(name.name, name.len);
 342
 343                 error = gfs2_dir_search(sdp->sd_jindex, &name, NULL, NULL);
 344                 if (error == -ENOENT) {
 345                         error = 0;
 346                         break;
 347                 }
 348
 349                 gfs2_glock_dq_uninit(ji_gh);
 350
 351                 if (error)
 352                         break;
 353
 354                 error = -ENOMEM;
 355                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 356                 if (!jd)
 357                         break;
 358
 359                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 360                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 361                         if (!jd->jd_inode)
 362                                 error = -ENOENT;
 363                         else
 364                                 error = PTR_ERR(jd->jd_inode);
 365                         kfree(jd);
 366                         break;
 367                 }
 368
 369                 spin_lock(&sdp->sd_jindex_spin);
 370                 jd->jd_jid = sdp->sd_journals++;
 371                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 372                 spin_unlock(&sdp->sd_jindex_spin);
 373         }
 374
 375         mutex_unlock(&sdp->sd_jindex_mutex);
 376
 377         return error;
 378 }
 379
 380 /**
 381  * gfs2_jindex_free - Clear all the journal index information
 382  * @sdp: The GFS2 superblock
 383  *
 384  */
 385
 386 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 387 {
 388         struct list_head list;
 389         struct gfs2_jdesc *jd;
 390
 391         spin_lock(&sdp->sd_jindex_spin);
 392         list_add(&list, &sdp->sd_jindex_list);
 393         list_del_init(&sdp->sd_jindex_list);
 394         sdp->sd_journals = 0;
 395         spin_unlock(&sdp->sd_jindex_spin);
 396
 397         while (!list_empty(&list)) {
 398                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 399                 list_del(&jd->jd_list);
 400                 iput(jd->jd_inode);
 401                 kfree(jd);
 402         }
 403 }
 404
 405 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 406 {
 407         struct gfs2_jdesc *jd;
 408         int found = 0;
 409
 410         list_for_each_entry(jd, head, jd_list) {
 411                 if (jd->jd_jid == jid) {
 412                         found = 1;
 413                         break;
 414                 }
 415         }
 416
 417         if (!found)
 418                 jd = NULL;
 419
 420         return jd;
 421 }
 422
 423 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 424 {
 425         struct gfs2_jdesc *jd;
 426
 427         spin_lock(&sdp->sd_jindex_spin);
 428         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 429         spin_unlock(&sdp->sd_jindex_spin);
 430
 431         return jd;
 432 }
 433
 434 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 435 {
 436         struct gfs2_jdesc *jd;
 437
 438         spin_lock(&sdp->sd_jindex_spin);
 439         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 440         if (jd)
 441                 jd->jd_dirty = 1;
 442         spin_unlock(&sdp->sd_jindex_spin);
 443 }
 444
 445 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 446 {
 447         struct gfs2_jdesc *jd;
 448         int found = 0;
 449
 450         spin_lock(&sdp->sd_jindex_spin);
 451
 452         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 453                 if (jd->jd_dirty) {
 454                         jd->jd_dirty = 0;
 455                         found = 1;
 456                         break;
 457                 }
 458         }
 459         spin_unlock(&sdp->sd_jindex_spin);
 460
 461         if (!found)
 462                 jd = NULL;
 463
 464         return jd;
 465 }
 466
 467 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 468 {
 469         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 470         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 471         int ar;
 472         int error;
 473
 474         if (ip->i_di.di_size < (8 << 20) || ip->i_di.di_size > (1 << 30) ||
 475             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 476                 gfs2_consist_inode(ip);
 477                 return -EIO;
 478         }
 479         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 480
 481         error = gfs2_write_alloc_required(ip, 0, ip->i_di.di_size, &ar);
 482         if (!error && ar) {
 483                 gfs2_consist_inode(ip);
 484                 error = -EIO;
 485         }
 486
 487         return error;
 488 }
 489
 490 /**
 491  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 492  * @sdp: the filesystem
 493  *
 494  * Returns: errno
 495  */
 496
 497 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 498 {
 499         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 500         struct gfs2_glock *j_gl = ip->i_gl;
 501         struct gfs2_holder t_gh;
 502         struct gfs2_log_header head;
 503         int error;
 504
 505         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 506                                    GL_LOCAL_EXCL, &t_gh);
 507         if (error)
 508                 return error;
 509
 510         gfs2_meta_cache_flush(ip);
 511         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
 512
 513         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 514         if (error)
 515                 goto fail;
 516
 517         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 518                 gfs2_consist(sdp);
 519                 error = -EIO;
 520                 goto fail;
 521         }
 522
 523         /*  Initialize some head of the log stuff  */
 524         sdp->sd_log_sequence = head.lh_sequence + 1;
 525         gfs2_log_pointers_init(sdp, head.lh_blkno);
 526
 527         error = gfs2_quota_init(sdp);
 528         if (error)
 529                 goto fail_unlinked;
 530
 531         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 532
 533         gfs2_glock_dq_uninit(&t_gh);
 534
 535         return 0;
 536
 537  fail_unlinked:
 538
 539  fail:
 540         t_gh.gh_flags |= GL_NOCACHE;
 541         gfs2_glock_dq_uninit(&t_gh);
 542
 543         return error;
 544 }
 545
 546 /**
 547  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 548  * @sdp: the filesystem
 549  *
 550  * Returns: errno
 551  */
 552
 553 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 554 {
 555         struct gfs2_holder t_gh;
 556         int error;
 557
 558         gfs2_quota_sync(sdp);
 559         gfs2_statfs_sync(sdp);
 560
 561         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 562                                 GL_LOCAL_EXCL | GL_NOCACHE,
 563                                 &t_gh);
 564         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 565                 return error;
 566
 567         gfs2_meta_syncfs(sdp);
 568         gfs2_log_shutdown(sdp);
 569
 570         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 571
 572         if (t_gh.gh_gl)
 573                 gfs2_glock_dq_uninit(&t_gh);
 574
 575         gfs2_quota_cleanup(sdp);
 576
 577         return error;
 578 }
 579
 580 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 581 {
 582         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 583         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 584         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 585         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 586         struct buffer_head *m_bh, *l_bh;
 587         struct gfs2_holder gh;
 588         int error;
 589
 590         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 591                                    &gh);
 592         if (error)
 593                 return error;
 594
 595         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 596         if (error)
 597                 goto out;
 598
 599         if (sdp->sd_args.ar_spectator) {
 600                 spin_lock(&sdp->sd_statfs_spin);
 601                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 602                                       sizeof(struct gfs2_dinode));
 603                 spin_unlock(&sdp->sd_statfs_spin);
 604         } else {
 605                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 606                 if (error)
 607                         goto out_m_bh;
 608
 609                 spin_lock(&sdp->sd_statfs_spin);
 610                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 611                                       sizeof(struct gfs2_dinode));
 612                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 613                                       sizeof(struct gfs2_dinode));
 614                 spin_unlock(&sdp->sd_statfs_spin);
 615
 616                 brelse(l_bh);
 617         }
 618
 619  out_m_bh:
 620         brelse(m_bh);
 621
 622  out:
 623         gfs2_glock_dq_uninit(&gh);
 624
 625         return 0;
 626 }
 627
 628 void gfs2_statfs_change(struct gfs2_sbd *sdp, int64_t total, int64_t free,
 629                         int64_t dinodes)
 630 {
 631         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 632         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 633         struct buffer_head *l_bh;
 634         int error;
 635
 636         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 637         if (error)
 638                 return;
 639
 640         mutex_lock(&sdp->sd_statfs_mutex);
 641         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 642         mutex_unlock(&sdp->sd_statfs_mutex);
 643
 644         spin_lock(&sdp->sd_statfs_spin);
 645         l_sc->sc_total += total;
 646         l_sc->sc_free += free;
 647         l_sc->sc_dinodes += dinodes;
 648         gfs2_statfs_change_out(l_sc, l_bh->b_data +
 649                                sizeof(struct gfs2_dinode));
 650         spin_unlock(&sdp->sd_statfs_spin);
 651
 652         brelse(l_bh);
 653 }
 654
 655 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 656 {
 657         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 658         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 659         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 660         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 661         struct gfs2_holder gh;
 662         struct buffer_head *m_bh, *l_bh;
 663         int error;
 664
 665         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 666                                    &gh);
 667         if (error)
 668                 return error;
 669
 670         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 671         if (error)
 672                 goto out;
 673
 674         spin_lock(&sdp->sd_statfs_spin);
 675         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 676                               sizeof(struct gfs2_dinode));
 677         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 678                 spin_unlock(&sdp->sd_statfs_spin);
 679                 goto out_bh;
 680         }
 681         spin_unlock(&sdp->sd_statfs_spin);
 682
 683         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 684         if (error)
 685                 goto out_bh;
 686
 687         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 688         if (error)
 689                 goto out_bh2;
 690
 691         mutex_lock(&sdp->sd_statfs_mutex);
 692         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 693         mutex_unlock(&sdp->sd_statfs_mutex);
 694
 695         spin_lock(&sdp->sd_statfs_spin);
 696         m_sc->sc_total += l_sc->sc_total;
 697         m_sc->sc_free += l_sc->sc_free;
 698         m_sc->sc_dinodes += l_sc->sc_dinodes;
 699         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 700         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 701                0, sizeof(struct gfs2_statfs_change));
 702         spin_unlock(&sdp->sd_statfs_spin);
 703
 704         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 705         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 706
 707         gfs2_trans_end(sdp);
 708
 709  out_bh2:
 710         brelse(l_bh);
 711
 712  out_bh:
 713         brelse(m_bh);
 714
 715  out:
 716         gfs2_glock_dq_uninit(&gh);
 717
 718         return error;
 719 }
 720
 721 /**
 722  * gfs2_statfs_i - Do a statfs
 723  * @sdp: the filesystem
 724  * @sg: the sg structure
 725  *
 726  * Returns: errno
 727  */
 728
 729 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 730 {
 731         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 732         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 733
 734         spin_lock(&sdp->sd_statfs_spin);
 735
 736         *sc = *m_sc;
 737         sc->sc_total += l_sc->sc_total;
 738         sc->sc_free += l_sc->sc_free;
 739         sc->sc_dinodes += l_sc->sc_dinodes;
 740
 741         spin_unlock(&sdp->sd_statfs_spin);
 742
 743         if (sc->sc_free < 0)
 744                 sc->sc_free = 0;
 745         if (sc->sc_free > sc->sc_total)
 746                 sc->sc_free = sc->sc_total;
 747         if (sc->sc_dinodes < 0)
 748                 sc->sc_dinodes = 0;
 749
 750         return 0;
 751 }
 752
 753 /**
 754  * statfs_fill - fill in the sg for a given RG
 755  * @rgd: the RG
 756  * @sc: the sc structure
 757  *
 758  * Returns: 0 on success, -ESTALE if the LVB is invalid
 759  */
 760
 761 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 762                             struct gfs2_statfs_change *sc)
 763 {
 764         gfs2_rgrp_verify(rgd);
 765         sc->sc_total += rgd->rd_ri.ri_data;
 766         sc->sc_free += rgd->rd_rg.rg_free;
 767         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 768         return 0;
 769 }
 770
 771 /**
 772  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 773  * @sdp: the filesystem
 774  * @sc: the sc info that will be returned
 775  *
 776  * Any error (other than a signal) will cause this routine to fall back
 777  * to the synchronous version.
 778  *
 779  * FIXME: This really shouldn't busy wait like this.
 780  *
 781  * Returns: errno
 782  */
 783
 784 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 785 {
 786         struct gfs2_holder ri_gh;
 787         struct gfs2_rgrpd *rgd_next;
 788         struct gfs2_holder *gha, *gh;
 789         unsigned int slots = 64;
 790         unsigned int x;
 791         int done;
 792         int error = 0, err;
 793
 794         memset(sc, 0, sizeof(struct gfs2_statfs_change));
 795         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 796         if (!gha)
 797                 return -ENOMEM;
 798
 799         error = gfs2_rindex_hold(sdp, &ri_gh);
 800         if (error)
 801                 goto out;
 802
 803         rgd_next = gfs2_rgrpd_get_first(sdp);
 804
 805         for (;;) {
 806                 done = 1;
 807
 808                 for (x = 0; x < slots; x++) {
 809                         gh = gha + x;
 810
 811                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 812                                 err = gfs2_glock_wait(gh);
 813                                 if (err) {
 814                                         gfs2_holder_uninit(gh);
 815                                         error = err;
 816                                 } else {
 817                                         if (!error)
 818                                                 error = statfs_slow_fill(
 819                                                         gh->gh_gl->gl_object, sc);
 820                                         gfs2_glock_dq_uninit(gh);
 821                                 }
 822                         }
 823
 824                         if (gh->gh_gl)
 825                                 done = 0;
 826                         else if (rgd_next && !error) {
 827                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 828                                                            LM_ST_SHARED,
 829                                                            GL_ASYNC,
 830                                                            gh);
 831                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 832                                 done = 0;
 833                         }
 834
 835                         if (signal_pending(current))
 836                                 error = -ERESTARTSYS;
 837                 }
 838
 839                 if (done)
 840                         break;
 841
 842                 yield();
 843         }
 844
 845         gfs2_glock_dq_uninit(&ri_gh);
 846
 847  out:
 848         kfree(gha);
 849
 850         return error;
 851 }
 852
 853 struct lfcc {
 854         struct list_head list;
 855         struct gfs2_holder gh;
 856 };
 857
 858 /**
 859  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 860  *                            journals are clean
 861  * @sdp: the file system
 862  * @state: the state to put the transaction lock into
 863  * @t_gh: the hold on the transaction lock
 864  *
 865  * Returns: errno
 866  */
 867
 868 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 869                                     struct gfs2_holder *t_gh)
 870 {
 871         struct gfs2_inode *ip;
 872         struct gfs2_holder ji_gh;
 873         struct gfs2_jdesc *jd;
 874         struct lfcc *lfcc;
 875         LIST_HEAD(list);
 876         struct gfs2_log_header lh;
 877         int error;
 878
 879         error = gfs2_jindex_hold(sdp, &ji_gh);
 880         if (error)
 881                 return error;
 882
 883         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 884                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 885                 if (!lfcc) {
 886                         error = -ENOMEM;
 887                         goto out;
 888                 }
 889                 ip = GFS2_I(jd->jd_inode);
 890                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 891                 if (error) {
 892                         kfree(lfcc);
 893                         goto out;
 894                 }
 895                 list_add(&lfcc->list, &list);
 896         }
 897
 898         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 899                                LM_FLAG_PRIORITY | GL_NOCACHE,
 900                                t_gh);
 901
 902         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 903                 error = gfs2_jdesc_check(jd);
 904                 if (error)
 905                         break;
 906                 error = gfs2_find_jhead(jd, &lh);
 907                 if (error)
 908                         break;
 909                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 910                         error = -EBUSY;
 911                         break;
 912                 }
 913         }
 914
 915         if (error)
 916                 gfs2_glock_dq_uninit(t_gh);
 917
 918  out:
 919         while (!list_empty(&list)) {
 920                 lfcc = list_entry(list.next, struct lfcc, list);
 921                 list_del(&lfcc->list);
 922                 gfs2_glock_dq_uninit(&lfcc->gh);
 923                 kfree(lfcc);
 924         }
 925         gfs2_glock_dq_uninit(&ji_gh);
 926
 927         return error;
 928 }
 929
 930 /**
 931  * gfs2_freeze_fs - freezes the file system
 932  * @sdp: the file system
 933  *
 934  * This function flushes data and meta data for all machines by
 935  * aquiring the transaction log exclusively.  All journals are
 936  * ensured to be in a clean state as well.
 937  *
 938  * Returns: errno
 939  */
 940
 941 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 942 {
 943         int error = 0;
 944
 945         mutex_lock(&sdp->sd_freeze_lock);
 946
 947         if (!sdp->sd_freeze_count++) {
 948                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 949                 if (error)
 950                         sdp->sd_freeze_count--;
 951         }
 952
 953         mutex_unlock(&sdp->sd_freeze_lock);
 954
 955         return error;
 956 }
 957
 958 /**
 959  * gfs2_unfreeze_fs - unfreezes the file system
 960  * @sdp: the file system
 961  *
 962  * This function allows the file system to proceed by unlocking
 963  * the exclusively held transaction lock.  Other GFS2 nodes are
 964  * now free to acquire the lock shared and go on with their lives.
 965  *
 966  */
 967
 968 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 969 {
 970         mutex_lock(&sdp->sd_freeze_lock);
 971
 972         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 973                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 974
 975         mutex_unlock(&sdp->sd_freeze_lock);
 976 }
 977