drivers/block/pktcdvd.c

   1 /*
   2  * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
   3  * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
   4  * Copyright (C) 2006 Thomas Maier <balagi@justmail.de>
   5  *
   6  * May be copied or modified under the terms of the GNU General Public
   7  * License.  See linux/COPYING for more information.
   8  *
   9  * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
  10  * DVD-RAM devices.
  11  *
  12  * Theory of operation:
  13  *
  14  * At the lowest level, there is the standard driver for the CD/DVD device,
  15  * typically ide-cd.c or sr.c. This driver can handle read and write requests,
  16  * but it doesn't know anything about the special restrictions that apply to
  17  * packet writing. One restriction is that write requests must be aligned to
  18  * packet boundaries on the physical media, and the size of a write request
  19  * must be equal to the packet size. Another restriction is that a
  20  * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
  21  * command, if the previous command was a write.
  22  *
  23  * The purpose of the packet writing driver is to hide these restrictions from
  24  * higher layers, such as file systems, and present a block device that can be
  25  * randomly read and written using 2kB-sized blocks.
  26  *
  27  * The lowest layer in the packet writing driver is the packet I/O scheduler.
  28  * Its data is defined by the struct packet_iosched and includes two bio
  29  * queues with pending read and write requests. These queues are processed
  30  * by the pkt_iosched_process_queue() function. The write requests in this
  31  * queue are already properly aligned and sized. This layer is responsible for
  32  * issuing the flush cache commands and scheduling the I/O in a good order.
  33  *
  34  * The next layer transforms unaligned write requests to aligned writes. This
  35  * transformation requires reading missing pieces of data from the underlying
  36  * block device, assembling the pieces to full packets and queuing them to the
  37  * packet I/O scheduler.
  38  *
  39  * At the top layer there is a custom make_request_fn function that forwards
  40  * read requests directly to the iosched queue and puts write requests in the
  41  * unaligned write queue. A kernel thread performs the necessary read
  42  * gathering to convert the unaligned writes to aligned writes and then feeds
  43  * them to the packet I/O scheduler.
  44  *
  45  *************************************************************************/
  46
  47 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  48
  49 #include <linux/pktcdvd.h>
  50 #include <linux/module.h>
  51 #include <linux/types.h>
  52 #include <linux/kernel.h>
  53 #include <linux/compat.h>
  54 #include <linux/kthread.h>
  55 #include <linux/errno.h>
  56 #include <linux/spinlock.h>
  57 #include <linux/file.h>
  58 #include <linux/proc_fs.h>
  59 #include <linux/seq_file.h>
  60 #include <linux/miscdevice.h>
  61 #include <linux/freezer.h>
  62 #include <linux/mutex.h>
  63 #include <linux/slab.h>
  64 #include <scsi/scsi_cmnd.h>
  65 #include <scsi/scsi_ioctl.h>
  66 #include <scsi/scsi.h>
  67 #include <linux/debugfs.h>
  68 #include <linux/device.h>
  69
  70 #include <asm/uaccess.h>
  71
  72 #define DRIVER_NAME     "pktcdvd"
  73
  74 #if PACKET_DEBUG
  75 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  76 #else
  77 #define DPRINTK(fmt, args...)
  78 #endif
  79
  80 #if PACKET_DEBUG > 1
  81 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  82 #else
  83 #define VPRINTK(fmt, args...)
  84 #endif
  85
  86 #define MAX_SPEED 0xffff
  87
  88 static DEFINE_MUTEX(pktcdvd_mutex);
  89 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  90 static struct proc_dir_entry *pkt_proc;
  91 static int pktdev_major;
  92 static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
  93 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
  94 static struct mutex ctl_mutex;  /* Serialize open/close/setup/teardown */
  95 static mempool_t *psd_pool;
  96
  97 static struct class     *class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
  98 static struct dentry    *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
  99
 100 /* forward declaration */
 101 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
 102 static int pkt_remove_dev(dev_t pkt_dev);
 103 static int pkt_seq_show(struct seq_file *m, void *p);
 104
 105 static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
 106 {
 107         return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1);
 108 }
 109
 110 /*
 111  * create and register a pktcdvd kernel object.
 112  */
 113 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
 114                                         const char* name,
 115                                         struct kobject* parent,
 116                                         struct kobj_type* ktype)
 117 {
 118         struct pktcdvd_kobj *p;
 119         int error;
 120
 121         p = kzalloc(sizeof(*p), GFP_KERNEL);
 122         if (!p)
 123                 return NULL;
 124         p->pd = pd;
 125         error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
 126         if (error) {
 127                 kobject_put(&p->kobj);
 128                 return NULL;
 129         }
 130         kobject_uevent(&p->kobj, KOBJ_ADD);
 131         return p;
 132 }
 133 /*
 134  * remove a pktcdvd kernel object.
 135  */
 136 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 137 {
 138         if (p)
 139                 kobject_put(&p->kobj);
 140 }
 141 /*
 142  * default release function for pktcdvd kernel objects.
 143  */
 144 static void pkt_kobj_release(struct kobject *kobj)
 145 {
 146         kfree(to_pktcdvdkobj(kobj));
 147 }
 148
 149
 150 /**********************************************************
 151  *
 152  * sysfs interface for pktcdvd
 153  * by (C) 2006  Thomas Maier <balagi@justmail.de>
 154  *
 155  **********************************************************/
 156
 157 #define DEF_ATTR(_obj,_name,_mode) \
 158         static struct attribute _obj = { .name = _name, .mode = _mode }
 159
 160 /**********************************************************
 161   /sys/class/pktcdvd/pktcdvd[0-7]/
 162                      stat/reset
 163                      stat/packets_started
 164                      stat/packets_finished
 165                      stat/kb_written
 166                      stat/kb_read
 167                      stat/kb_read_gather
 168                      write_queue/size
 169                      write_queue/congestion_off
 170                      write_queue/congestion_on
 171  **********************************************************/
 172
 173 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 174 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 175 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 176 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 177 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 178 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 179
 180 static struct attribute *kobj_pkt_attrs_stat[] = {
 181         &kobj_pkt_attr_st1,
 182         &kobj_pkt_attr_st2,
 183         &kobj_pkt_attr_st3,
 184         &kobj_pkt_attr_st4,
 185         &kobj_pkt_attr_st5,
 186         &kobj_pkt_attr_st6,
 187         NULL
 188 };
 189
 190 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 191 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 192 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 193
 194 static struct attribute *kobj_pkt_attrs_wqueue[] = {
 195         &kobj_pkt_attr_wq1,
 196         &kobj_pkt_attr_wq2,
 197         &kobj_pkt_attr_wq3,
 198         NULL
 199 };
 200
 201 static ssize_t kobj_pkt_show(struct kobject *kobj,
 202                         struct attribute *attr, char *data)
 203 {
 204         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 205         int n = 0;
 206         int v;
 207         if (strcmp(attr->name, "packets_started") == 0) {
 208                 n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 209
 210         } else if (strcmp(attr->name, "packets_finished") == 0) {
 211                 n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 212
 213         } else if (strcmp(attr->name, "kb_written") == 0) {
 214                 n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 215
 216         } else if (strcmp(attr->name, "kb_read") == 0) {
 217                 n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 218
 219         } else if (strcmp(attr->name, "kb_read_gather") == 0) {
 220                 n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 221
 222         } else if (strcmp(attr->name, "size") == 0) {
 223                 spin_lock(&pd->lock);
 224                 v = pd->bio_queue_size;
 225                 spin_unlock(&pd->lock);
 226                 n = sprintf(data, "%d\n", v);
 227
 228         } else if (strcmp(attr->name, "congestion_off") == 0) {
 229                 spin_lock(&pd->lock);
 230                 v = pd->write_congestion_off;
 231                 spin_unlock(&pd->lock);
 232                 n = sprintf(data, "%d\n", v);
 233
 234         } else if (strcmp(attr->name, "congestion_on") == 0) {
 235                 spin_lock(&pd->lock);
 236                 v = pd->write_congestion_on;
 237                 spin_unlock(&pd->lock);
 238                 n = sprintf(data, "%d\n", v);
 239         }
 240         return n;
 241 }
 242
 243 static void init_write_congestion_marks(int* lo, int* hi)
 244 {
 245         if (*hi > 0) {
 246                 *hi = max(*hi, 500);
 247                 *hi = min(*hi, 1000000);
 248                 if (*lo <= 0)
 249                         *lo = *hi - 100;
 250                 else {
 251                         *lo = min(*lo, *hi - 100);
 252                         *lo = max(*lo, 100);
 253                 }
 254         } else {
 255                 *hi = -1;
 256                 *lo = -1;
 257         }
 258 }
 259
 260 static ssize_t kobj_pkt_store(struct kobject *kobj,
 261                         struct attribute *attr,
 262                         const char *data, size_t len)
 263 {
 264         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 265         int val;
 266
 267         if (strcmp(attr->name, "reset") == 0 && len > 0) {
 268                 pd->stats.pkt_started = 0;
 269                 pd->stats.pkt_ended = 0;
 270                 pd->stats.secs_w = 0;
 271                 pd->stats.secs_rg = 0;
 272                 pd->stats.secs_r = 0;
 273
 274         } else if (strcmp(attr->name, "congestion_off") == 0
 275                    && sscanf(data, "%d", &val) == 1) {
 276                 spin_lock(&pd->lock);
 277                 pd->write_congestion_off = val;
 278                 init_write_congestion_marks(&pd->write_congestion_off,
 279                                         &pd->write_congestion_on);
 280                 spin_unlock(&pd->lock);
 281
 282         } else if (strcmp(attr->name, "congestion_on") == 0
 283                    && sscanf(data, "%d", &val) == 1) {
 284                 spin_lock(&pd->lock);
 285                 pd->write_congestion_on = val;
 286                 init_write_congestion_marks(&pd->write_congestion_off,
 287                                         &pd->write_congestion_on);
 288                 spin_unlock(&pd->lock);
 289         }
 290         return len;
 291 }
 292
 293 static const struct sysfs_ops kobj_pkt_ops = {
 294         .show = kobj_pkt_show,
 295         .store = kobj_pkt_store
 296 };
 297 static struct kobj_type kobj_pkt_type_stat = {
 298         .release = pkt_kobj_release,
 299         .sysfs_ops = &kobj_pkt_ops,
 300         .default_attrs = kobj_pkt_attrs_stat
 301 };
 302 static struct kobj_type kobj_pkt_type_wqueue = {
 303         .release = pkt_kobj_release,
 304         .sysfs_ops = &kobj_pkt_ops,
 305         .default_attrs = kobj_pkt_attrs_wqueue
 306 };
 307
 308 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 309 {
 310         if (class_pktcdvd) {
 311                 pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
 312                                         "%s", pd->name);
 313                 if (IS_ERR(pd->dev))
 314                         pd->dev = NULL;
 315         }
 316         if (pd->dev) {
 317                 pd->kobj_stat = pkt_kobj_create(pd, "stat",
 318                                         &pd->dev->kobj,
 319                                         &kobj_pkt_type_stat);
 320                 pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 321                                         &pd->dev->kobj,
 322                                         &kobj_pkt_type_wqueue);
 323         }
 324 }
 325
 326 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 327 {
 328         pkt_kobj_remove(pd->kobj_stat);
 329         pkt_kobj_remove(pd->kobj_wqueue);
 330         if (class_pktcdvd)
 331                 device_unregister(pd->dev);
 332 }
 333
 334
 335 /********************************************************************
 336   /sys/class/pktcdvd/
 337                      add            map block device
 338                      remove         unmap packet dev
 339                      device_map     show mappings
 340  *******************************************************************/
 341
 342 static void class_pktcdvd_release(struct class *cls)
 343 {
 344         kfree(cls);
 345 }
 346 static ssize_t class_pktcdvd_show_map(struct class *c,
 347                                         struct class_attribute *attr,
 348                                         char *data)
 349 {
 350         int n = 0;
 351         int idx;
 352         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 353         for (idx = 0; idx < MAX_WRITERS; idx++) {
 354                 struct pktcdvd_device *pd = pkt_devs[idx];
 355                 if (!pd)
 356                         continue;
 357                 n += sprintf(data+n, "%s %u:%u %u:%u\n",
 358                         pd->name,
 359                         MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 360                         MAJOR(pd->bdev->bd_dev),
 361                         MINOR(pd->bdev->bd_dev));
 362         }
 363         mutex_unlock(&ctl_mutex);
 364         return n;
 365 }
 366
 367 static ssize_t class_pktcdvd_store_add(struct class *c,
 368                                         struct class_attribute *attr,
 369                                         const char *buf,
 370                                         size_t count)
 371 {
 372         unsigned int major, minor;
 373
 374         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 375                 /* pkt_setup_dev() expects caller to hold reference to self */
 376                 if (!try_module_get(THIS_MODULE))
 377                         return -ENODEV;
 378
 379                 pkt_setup_dev(MKDEV(major, minor), NULL);
 380
 381                 module_put(THIS_MODULE);
 382
 383                 return count;
 384         }
 385
 386         return -EINVAL;
 387 }
 388
 389 static ssize_t class_pktcdvd_store_remove(struct class *c,
 390                                           struct class_attribute *attr,
 391                                           const char *buf,
 392                                         size_t count)
 393 {
 394         unsigned int major, minor;
 395         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 396                 pkt_remove_dev(MKDEV(major, minor));
 397                 return count;
 398         }
 399         return -EINVAL;
 400 }
 401
 402 static struct class_attribute class_pktcdvd_attrs[] = {
 403  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 404  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 405  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 406  __ATTR_NULL
 407 };
 408
 409
 410 static int pkt_sysfs_init(void)
 411 {
 412         int ret = 0;
 413
 414         /*
 415          * create control files in sysfs
 416          * /sys/class/pktcdvd/...
 417          */
 418         class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 419         if (!class_pktcdvd)
 420                 return -ENOMEM;
 421         class_pktcdvd->name = DRIVER_NAME;
 422         class_pktcdvd->owner = THIS_MODULE;
 423         class_pktcdvd->class_release = class_pktcdvd_release;
 424         class_pktcdvd->class_attrs = class_pktcdvd_attrs;
 425         ret = class_register(class_pktcdvd);
 426         if (ret) {
 427                 kfree(class_pktcdvd);
 428                 class_pktcdvd = NULL;
 429                 pr_err("failed to create class pktcdvd\n");
 430                 return ret;
 431         }
 432         return 0;
 433 }
 434
 435 static void pkt_sysfs_cleanup(void)
 436 {
 437         if (class_pktcdvd)
 438                 class_destroy(class_pktcdvd);
 439         class_pktcdvd = NULL;
 440 }
 441
 442 /********************************************************************
 443   entries in debugfs
 444
 445   /sys/kernel/debug/pktcdvd[0-7]/
 446                         info
 447
 448  *******************************************************************/
 449
 450 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 451 {
 452         return pkt_seq_show(m, p);
 453 }
 454
 455 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 456 {
 457         return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 458 }
 459
 460 static const struct file_operations debug_fops = {
 461         .open           = pkt_debugfs_fops_open,
 462         .read           = seq_read,
 463         .llseek         = seq_lseek,
 464         .release        = single_release,
 465         .owner          = THIS_MODULE,
 466 };
 467
 468 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 469 {
 470         if (!pkt_debugfs_root)
 471                 return;
 472         pd->dfs_f_info = NULL;
 473         pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 474         if (IS_ERR(pd->dfs_d_root)) {
 475                 pd->dfs_d_root = NULL;
 476                 return;
 477         }
 478         pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
 479                                 pd->dfs_d_root, pd, &debug_fops);
 480         if (IS_ERR(pd->dfs_f_info)) {
 481                 pd->dfs_f_info = NULL;
 482                 return;
 483         }
 484 }
 485
 486 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 487 {
 488         if (!pkt_debugfs_root)
 489                 return;
 490         if (pd->dfs_f_info)
 491                 debugfs_remove(pd->dfs_f_info);
 492         pd->dfs_f_info = NULL;
 493         if (pd->dfs_d_root)
 494                 debugfs_remove(pd->dfs_d_root);
 495         pd->dfs_d_root = NULL;
 496 }
 497
 498 static void pkt_debugfs_init(void)
 499 {
 500         pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 501         if (IS_ERR(pkt_debugfs_root)) {
 502                 pkt_debugfs_root = NULL;
 503                 return;
 504         }
 505 }
 506
 507 static void pkt_debugfs_cleanup(void)
 508 {
 509         if (!pkt_debugfs_root)
 510                 return;
 511         debugfs_remove(pkt_debugfs_root);
 512         pkt_debugfs_root = NULL;
 513 }
 514
 515 /* ----------------------------------------------------------*/
 516
 517
 518 static void pkt_bio_finished(struct pktcdvd_device *pd)
 519 {
 520         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 521         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 522                 VPRINTK(DRIVER_NAME": queue empty\n");
 523                 atomic_set(&pd->iosched.attention, 1);
 524                 wake_up(&pd->wqueue);
 525         }
 526 }
 527
 528 /*
 529  * Allocate a packet_data struct
 530  */
 531 static struct packet_data *pkt_alloc_packet_data(int frames)
 532 {
 533         int i;
 534         struct packet_data *pkt;
 535
 536         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 537         if (!pkt)
 538                 goto no_pkt;
 539
 540         pkt->frames = frames;
 541         pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
 542         if (!pkt->w_bio)
 543                 goto no_bio;
 544
 545         for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 546                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 547                 if (!pkt->pages[i])
 548                         goto no_page;
 549         }
 550
 551         spin_lock_init(&pkt->lock);
 552         bio_list_init(&pkt->orig_bios);
 553
 554         for (i = 0; i < frames; i++) {
 555                 struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
 556                 if (!bio)
 557                         goto no_rd_bio;
 558
 559                 pkt->r_bios[i] = bio;
 560         }
 561
 562         return pkt;
 563
 564 no_rd_bio:
 565         for (i = 0; i < frames; i++) {
 566                 struct bio *bio = pkt->r_bios[i];
 567                 if (bio)
 568                         bio_put(bio);
 569         }
 570
 571 no_page:
 572         for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 573                 if (pkt->pages[i])
 574                         __free_page(pkt->pages[i]);
 575         bio_put(pkt->w_bio);
 576 no_bio:
 577         kfree(pkt);
 578 no_pkt:
 579         return NULL;
 580 }
 581
 582 /*
 583  * Free a packet_data struct
 584  */
 585 static void pkt_free_packet_data(struct packet_data *pkt)
 586 {
 587         int i;
 588
 589         for (i = 0; i < pkt->frames; i++) {
 590                 struct bio *bio = pkt->r_bios[i];
 591                 if (bio)
 592                         bio_put(bio);
 593         }
 594         for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 595                 __free_page(pkt->pages[i]);
 596         bio_put(pkt->w_bio);
 597         kfree(pkt);
 598 }
 599
 600 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 601 {
 602         struct packet_data *pkt, *next;
 603
 604         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 605
 606         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 607                 pkt_free_packet_data(pkt);
 608         }
 609         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 610 }
 611
 612 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 613 {
 614         struct packet_data *pkt;
 615
 616         BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 617
 618         while (nr_packets > 0) {
 619                 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 620                 if (!pkt) {
 621                         pkt_shrink_pktlist(pd);
 622                         return 0;
 623                 }
 624                 pkt->id = nr_packets;
 625                 pkt->pd = pd;
 626                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 627                 nr_packets--;
 628         }
 629         return 1;
 630 }
 631
 632 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 633 {
 634         struct rb_node *n = rb_next(&node->rb_node);
 635         if (!n)
 636                 return NULL;
 637         return rb_entry(n, struct pkt_rb_node, rb_node);
 638 }
 639
 640 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 641 {
 642         rb_erase(&node->rb_node, &pd->bio_queue);
 643         mempool_free(node, pd->rb_pool);
 644         pd->bio_queue_size--;
 645         BUG_ON(pd->bio_queue_size < 0);
 646 }
 647
 648 /*
 649  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 650  */
 651 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 652 {
 653         struct rb_node *n = pd->bio_queue.rb_node;
 654         struct rb_node *next;
 655         struct pkt_rb_node *tmp;
 656
 657         if (!n) {
 658                 BUG_ON(pd->bio_queue_size > 0);
 659                 return NULL;
 660         }
 661
 662         for (;;) {
 663                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 664                 if (s <= tmp->bio->bi_sector)
 665                         next = n->rb_left;
 666                 else
 667                         next = n->rb_right;
 668                 if (!next)
 669                         break;
 670                 n = next;
 671         }
 672
 673         if (s > tmp->bio->bi_sector) {
 674                 tmp = pkt_rbtree_next(tmp);
 675                 if (!tmp)
 676                         return NULL;
 677         }
 678         BUG_ON(s > tmp->bio->bi_sector);
 679         return tmp;
 680 }
 681
 682 /*
 683  * Insert a node into the pd->bio_queue rb tree.
 684  */
 685 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 686 {
 687         struct rb_node **p = &pd->bio_queue.rb_node;
 688         struct rb_node *parent = NULL;
 689         sector_t s = node->bio->bi_sector;
 690         struct pkt_rb_node *tmp;
 691
 692         while (*p) {
 693                 parent = *p;
 694                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 695                 if (s < tmp->bio->bi_sector)
 696                         p = &(*p)->rb_left;
 697                 else
 698                         p = &(*p)->rb_right;
 699         }
 700         rb_link_node(&node->rb_node, parent, p);
 701         rb_insert_color(&node->rb_node, &pd->bio_queue);
 702         pd->bio_queue_size++;
 703 }
 704
 705 /*
 706  * Send a packet_command to the underlying block device and
 707  * wait for completion.
 708  */
 709 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 710 {
 711         struct request_queue *q = bdev_get_queue(pd->bdev);
 712         struct request *rq;
 713         int ret = 0;
 714
 715         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 716                              WRITE : READ, __GFP_WAIT);
 717
 718         if (cgc->buflen) {
 719                 if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
 720                         goto out;
 721         }
 722
 723         rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 724         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 725
 726         rq->timeout = 60*HZ;
 727         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 728         if (cgc->quiet)
 729                 rq->cmd_flags |= REQ_QUIET;
 730
 731         blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 732         if (rq->errors)
 733                 ret = -EIO;
 734 out:
 735         blk_put_request(rq);
 736         return ret;
 737 }
 738
 739 static const char *sense_key_string(__u8 index)
 740 {
 741         static const char * const info[] = {
 742                 "No sense", "Recovered error", "Not ready",
 743                 "Medium error", "Hardware error", "Illegal request",
 744                 "Unit attention", "Data protect", "Blank check",
 745         };
 746
 747         return index < ARRAY_SIZE(info) ? info[index] : "INVALID";
 748 }
 749
 750 /*
 751  * A generic sense dump / resolve mechanism should be implemented across
 752  * all ATAPI + SCSI devices.
 753  */
 754 static void pkt_dump_sense(struct packet_command *cgc)
 755 {
 756         struct request_sense *sense = cgc->sense;
 757
 758         if (sense)
 759                 pr_err("%*ph - sense %02x.%02x.%02x (%s)\n",
 760                        CDROM_PACKET_SIZE, cgc->cmd,
 761                        sense->sense_key, sense->asc, sense->ascq,
 762                        sense_key_string(sense->sense_key));
 763         else
 764                 pr_err("%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
 765 }
 766
 767 /*
 768  * flush the drive cache to media
 769  */
 770 static int pkt_flush_cache(struct pktcdvd_device *pd)
 771 {
 772         struct packet_command cgc;
 773
 774         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 775         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 776         cgc.quiet = 1;
 777
 778         /*
 779          * the IMMED bit -- we default to not setting it, although that
 780          * would allow a much faster close, this is safer
 781          */
 782 #if 0
 783         cgc.cmd[1] = 1 << 1;
 784 #endif
 785         return pkt_generic_packet(pd, &cgc);
 786 }
 787
 788 /*
 789  * speed is given as the normal factor, e.g. 4 for 4x
 790  */
 791 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 792                                 unsigned write_speed, unsigned read_speed)
 793 {
 794         struct packet_command cgc;
 795         struct request_sense sense;
 796         int ret;
 797
 798         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 799         cgc.sense = &sense;
 800         cgc.cmd[0] = GPCMD_SET_SPEED;
 801         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 802         cgc.cmd[3] = read_speed & 0xff;
 803         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 804         cgc.cmd[5] = write_speed & 0xff;
 805
 806         if ((ret = pkt_generic_packet(pd, &cgc)))
 807                 pkt_dump_sense(&cgc);
 808
 809         return ret;
 810 }
 811
 812 /*
 813  * Queue a bio for processing by the low-level CD device. Must be called
 814  * from process context.
 815  */
 816 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 817 {
 818         spin_lock(&pd->iosched.lock);
 819         if (bio_data_dir(bio) == READ)
 820                 bio_list_add(&pd->iosched.read_queue, bio);
 821         else
 822                 bio_list_add(&pd->iosched.write_queue, bio);
 823         spin_unlock(&pd->iosched.lock);
 824
 825         atomic_set(&pd->iosched.attention, 1);
 826         wake_up(&pd->wqueue);
 827 }
 828
 829 /*
 830  * Process the queued read/write requests. This function handles special
 831  * requirements for CDRW drives:
 832  * - A cache flush command must be inserted before a read request if the
 833  *   previous request was a write.
 834  * - Switching between reading and writing is slow, so don't do it more often
 835  *   than necessary.
 836  * - Optimize for throughput at the expense of latency. This means that streaming
 837  *   writes will never be interrupted by a read, but if the drive has to seek
 838  *   before the next write, switch to reading instead if there are any pending
 839  *   read requests.
 840  * - Set the read speed according to current usage pattern. When only reading
 841  *   from the device, it's best to use the highest possible read speed, but
 842  *   when switching often between reading and writing, it's better to have the
 843  *   same read and write speeds.
 844  */
 845 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 846 {
 847
 848         if (atomic_read(&pd->iosched.attention) == 0)
 849                 return;
 850         atomic_set(&pd->iosched.attention, 0);
 851
 852         for (;;) {
 853                 struct bio *bio;
 854                 int reads_queued, writes_queued;
 855
 856                 spin_lock(&pd->iosched.lock);
 857                 reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 858                 writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 859                 spin_unlock(&pd->iosched.lock);
 860
 861                 if (!reads_queued && !writes_queued)
 862                         break;
 863
 864                 if (pd->iosched.writing) {
 865                         int need_write_seek = 1;
 866                         spin_lock(&pd->iosched.lock);
 867                         bio = bio_list_peek(&pd->iosched.write_queue);
 868                         spin_unlock(&pd->iosched.lock);
 869                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 870                                 need_write_seek = 0;
 871                         if (need_write_seek && reads_queued) {
 872                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 873                                         VPRINTK(DRIVER_NAME": write, waiting\n");
 874                                         break;
 875                                 }
 876                                 pkt_flush_cache(pd);
 877                                 pd->iosched.writing = 0;
 878                         }
 879                 } else {
 880                         if (!reads_queued && writes_queued) {
 881                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 882                                         VPRINTK(DRIVER_NAME": read, waiting\n");
 883                                         break;
 884                                 }
 885                                 pd->iosched.writing = 1;
 886                         }
 887                 }
 888
 889                 spin_lock(&pd->iosched.lock);
 890                 if (pd->iosched.writing)
 891                         bio = bio_list_pop(&pd->iosched.write_queue);
 892                 else
 893                         bio = bio_list_pop(&pd->iosched.read_queue);
 894                 spin_unlock(&pd->iosched.lock);
 895
 896                 if (!bio)
 897                         continue;
 898
 899                 if (bio_data_dir(bio) == READ)
 900                         pd->iosched.successive_reads += bio->bi_size >> 10;
 901                 else {
 902                         pd->iosched.successive_reads = 0;
 903                         pd->iosched.last_write = bio_end_sector(bio);
 904                 }
 905                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 906                         if (pd->read_speed == pd->write_speed) {
 907                                 pd->read_speed = MAX_SPEED;
 908                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 909                         }
 910                 } else {
 911                         if (pd->read_speed != pd->write_speed) {
 912                                 pd->read_speed = pd->write_speed;
 913                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 914                         }
 915                 }
 916
 917                 atomic_inc(&pd->cdrw.pending_bios);
 918                 generic_make_request(bio);
 919         }
 920 }
 921
 922 /*
 923  * Special care is needed if the underlying block device has a small
 924  * max_phys_segments value.
 925  */
 926 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 927 {
 928         if ((pd->settings.size << 9) / CD_FRAMESIZE
 929             <= queue_max_segments(q)) {
 930                 /*
 931                  * The cdrom device can handle one segment/frame
 932                  */
 933                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 934                 return 0;
 935         } else if ((pd->settings.size << 9) / PAGE_SIZE
 936                    <= queue_max_segments(q)) {
 937                 /*
 938                  * We can handle this case at the expense of some extra memory
 939                  * copies during write operations
 940                  */
 941                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 942                 return 0;
 943         } else {
 944                 pr_err("cdrom max_phys_segments too small\n");
 945                 return -EIO;
 946         }
 947 }
 948
 949 /*
 950  * Copy all data for this packet to pkt->pages[], so that
 951  * a) The number of required segments for the write bio is minimized, which
 952  *    is necessary for some scsi controllers.
 953  * b) The data can be used as cache to avoid read requests if we receive a
 954  *    new write request for the same zone.
 955  */
 956 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
 957 {
 958         int f, p, offs;
 959
 960         /* Copy all data to pkt->pages[] */
 961         p = 0;
 962         offs = 0;
 963         for (f = 0; f < pkt->frames; f++) {
 964                 if (bvec[f].bv_page != pkt->pages[p]) {
 965                         void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset;
 966                         void *vto = page_address(pkt->pages[p]) + offs;
 967                         memcpy(vto, vfrom, CD_FRAMESIZE);
 968                         kunmap_atomic(vfrom);
 969                         bvec[f].bv_page = pkt->pages[p];
 970                         bvec[f].bv_offset = offs;
 971                 } else {
 972                         BUG_ON(bvec[f].bv_offset != offs);
 973                 }
 974                 offs += CD_FRAMESIZE;
 975                 if (offs >= PAGE_SIZE) {
 976                         offs = 0;
 977                         p++;
 978                 }
 979         }
 980 }
 981
 982 static void pkt_end_io_read(struct bio *bio, int err)
 983 {
 984         struct packet_data *pkt = bio->bi_private;
 985         struct pktcdvd_device *pd = pkt->pd;
 986         BUG_ON(!pd);
 987
 988         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 989                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 990
 991         if (err)
 992                 atomic_inc(&pkt->io_errors);
 993         if (atomic_dec_and_test(&pkt->io_wait)) {
 994                 atomic_inc(&pkt->run_sm);
 995                 wake_up(&pd->wqueue);
 996         }
 997         pkt_bio_finished(pd);
 998 }
 999
1000 static void pkt_end_io_packet_write(struct bio *bio, int err)
1001 {
1002         struct packet_data *pkt = bio->bi_private;
1003         struct pktcdvd_device *pd = pkt->pd;
1004         BUG_ON(!pd);
1005
1006         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1007
1008         pd->stats.pkt_ended++;
1009
1010         pkt_bio_finished(pd);
1011         atomic_dec(&pkt->io_wait);
1012         atomic_inc(&pkt->run_sm);
1013         wake_up(&pd->wqueue);
1014 }
1015
1016 /*
1017  * Schedule reads for the holes in a packet
1018  */
1019 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1020 {
1021         int frames_read = 0;
1022         struct bio *bio;
1023         int f;
1024         char written[PACKET_MAX_SIZE];
1025
1026         BUG_ON(bio_list_empty(&pkt->orig_bios));
1027
1028         atomic_set(&pkt->io_wait, 0);
1029         atomic_set(&pkt->io_errors, 0);
1030
1031         /*
1032          * Figure out which frames we need to read before we can write.
1033          */
1034         memset(written, 0, sizeof(written));
1035         spin_lock(&pkt->lock);
1036         bio_list_for_each(bio, &pkt->orig_bios) {
1037                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1038                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1039                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1040                 BUG_ON(first_frame < 0);
1041                 BUG_ON(first_frame + num_frames > pkt->frames);
1042                 for (f = first_frame; f < first_frame + num_frames; f++)
1043                         written[f] = 1;
1044         }
1045         spin_unlock(&pkt->lock);
1046
1047         if (pkt->cache_valid) {
1048                 VPRINTK("pkt_gather_data: zone %llx cached\n",
1049                         (unsigned long long)pkt->sector);
1050                 goto out_account;
1051         }
1052
1053         /*
1054          * Schedule reads for missing parts of the packet.
1055          */
1056         for (f = 0; f < pkt->frames; f++) {
1057                 int p, offset;
1058
1059                 if (written[f])
1060                         continue;
1061
1062                 bio = pkt->r_bios[f];
1063                 bio_reset(bio);
1064                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1065                 bio->bi_bdev = pd->bdev;
1066                 bio->bi_end_io = pkt_end_io_read;
1067                 bio->bi_private = pkt;
1068
1069                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1070                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1071                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1072                         f, pkt->pages[p], offset);
1073                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1074                         BUG();
1075
1076                 atomic_inc(&pkt->io_wait);
1077                 bio->bi_rw = READ;
1078                 pkt_queue_bio(pd, bio);
1079                 frames_read++;
1080         }
1081
1082 out_account:
1083         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1084                 frames_read, (unsigned long long)pkt->sector);
1085         pd->stats.pkt_started++;
1086         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1087 }
1088
1089 /*
1090  * Find a packet matching zone, or the least recently used packet if
1091  * there is no match.
1092  */
1093 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1094 {
1095         struct packet_data *pkt;
1096
1097         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1098                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1099                         list_del_init(&pkt->list);
1100                         if (pkt->sector != zone)
1101                                 pkt->cache_valid = 0;
1102                         return pkt;
1103                 }
1104         }
1105         BUG();
1106         return NULL;
1107 }
1108
1109 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1110 {
1111         if (pkt->cache_valid) {
1112                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1113         } else {
1114                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1115         }
1116 }
1117
1118 /*
1119  * recover a failed write, query for relocation if possible
1120  *
1121  * returns 1 if recovery is possible, or 0 if not
1122  *
1123  */
1124 static int pkt_start_recovery(struct packet_data *pkt)
1125 {
1126         /*
1127          * FIXME. We need help from the file system to implement
1128          * recovery handling.
1129          */
1130         return 0;
1131 #if 0
1132         struct request *rq = pkt->rq;
1133         struct pktcdvd_device *pd = rq->rq_disk->private_data;
1134         struct block_device *pkt_bdev;
1135         struct super_block *sb = NULL;
1136         unsigned long old_block, new_block;
1137         sector_t new_sector;
1138
1139         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1140         if (pkt_bdev) {
1141                 sb = get_super(pkt_bdev);
1142                 bdput(pkt_bdev);
1143         }
1144
1145         if (!sb)
1146                 return 0;
1147
1148         if (!sb->s_op->relocate_blocks)
1149                 goto out;
1150
1151         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1152         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1153                 goto out;
1154
1155         new_sector = new_block * (CD_FRAMESIZE >> 9);
1156         pkt->sector = new_sector;
1157
1158         bio_reset(pkt->bio);
1159         pkt->bio->bi_bdev = pd->bdev;
1160         pkt->bio->bi_rw = REQ_WRITE;
1161         pkt->bio->bi_sector = new_sector;
1162         pkt->bio->bi_size = pkt->frames * CD_FRAMESIZE;
1163         pkt->bio->bi_vcnt = pkt->frames;
1164
1165         pkt->bio->bi_end_io = pkt_end_io_packet_write;
1166         pkt->bio->bi_private = pkt;
1167
1168         drop_super(sb);
1169         return 1;
1170
1171 out:
1172         drop_super(sb);
1173         return 0;
1174 #endif
1175 }
1176
1177 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1178 {
1179 #if PACKET_DEBUG > 1
1180         static const char *state_name[] = {
1181                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1182         };
1183         enum packet_data_state old_state = pkt->state;
1184         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1185                 state_name[old_state], state_name[state]);
1186 #endif
1187         pkt->state = state;
1188 }
1189
1190 /*
1191  * Scan the work queue to see if we can start a new packet.
1192  * returns non-zero if any work was done.
1193  */
1194 static int pkt_handle_queue(struct pktcdvd_device *pd)
1195 {
1196         struct packet_data *pkt, *p;
1197         struct bio *bio = NULL;
1198         sector_t zone = 0; /* Suppress gcc warning */
1199         struct pkt_rb_node *node, *first_node;
1200         struct rb_node *n;
1201         int wakeup;
1202
1203         VPRINTK("handle_queue\n");
1204
1205         atomic_set(&pd->scan_queue, 0);
1206
1207         if (list_empty(&pd->cdrw.pkt_free_list)) {
1208                 VPRINTK("handle_queue: no pkt\n");
1209                 return 0;
1210         }
1211
1212         /*
1213          * Try to find a zone we are not already working on.
1214          */
1215         spin_lock(&pd->lock);
1216         first_node = pkt_rbtree_find(pd, pd->current_sector);
1217         if (!first_node) {
1218                 n = rb_first(&pd->bio_queue);
1219                 if (n)
1220                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1221         }
1222         node = first_node;
1223         while (node) {
1224                 bio = node->bio;
1225                 zone = get_zone(bio->bi_sector, pd);
1226                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1227                         if (p->sector == zone) {
1228                                 bio = NULL;
1229                                 goto try_next_bio;
1230                         }
1231                 }
1232                 break;
1233 try_next_bio:
1234                 node = pkt_rbtree_next(node);
1235                 if (!node) {
1236                         n = rb_first(&pd->bio_queue);
1237                         if (n)
1238                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
1239                 }
1240                 if (node == first_node)
1241                         node = NULL;
1242         }
1243         spin_unlock(&pd->lock);
1244         if (!bio) {
1245                 VPRINTK("handle_queue: no bio\n");
1246                 return 0;
1247         }
1248
1249         pkt = pkt_get_packet_data(pd, zone);
1250
1251         pd->current_sector = zone + pd->settings.size;
1252         pkt->sector = zone;
1253         BUG_ON(pkt->frames != pd->settings.size >> 2);
1254         pkt->write_size = 0;
1255
1256         /*
1257          * Scan work queue for bios in the same zone and link them
1258          * to this packet.
1259          */
1260         spin_lock(&pd->lock);
1261         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1262         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1263                 bio = node->bio;
1264                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
1265                         (unsigned long long)get_zone(bio->bi_sector, pd));
1266                 if (get_zone(bio->bi_sector, pd) != zone)
1267                         break;
1268                 pkt_rbtree_erase(pd, node);
1269                 spin_lock(&pkt->lock);
1270                 bio_list_add(&pkt->orig_bios, bio);
1271                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1272                 spin_unlock(&pkt->lock);
1273         }
1274         /* check write congestion marks, and if bio_queue_size is
1275            below, wake up any waiters */
1276         wakeup = (pd->write_congestion_on > 0
1277                         && pd->bio_queue_size <= pd->write_congestion_off);
1278         spin_unlock(&pd->lock);
1279         if (wakeup) {
1280                 clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1281                                         BLK_RW_ASYNC);
1282         }
1283
1284         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1285         pkt_set_state(pkt, PACKET_WAITING_STATE);
1286         atomic_set(&pkt->run_sm, 1);
1287
1288         spin_lock(&pd->cdrw.active_list_lock);
1289         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1290         spin_unlock(&pd->cdrw.active_list_lock);
1291
1292         return 1;
1293 }
1294
1295 /*
1296  * Assemble a bio to write one packet and queue the bio for processing
1297  * by the underlying block device.
1298  */
1299 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1300 {
1301         int f;
1302         struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1303
1304         bio_reset(pkt->w_bio);
1305         pkt->w_bio->bi_sector = pkt->sector;
1306         pkt->w_bio->bi_bdev = pd->bdev;
1307         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1308         pkt->w_bio->bi_private = pkt;
1309
1310         /* XXX: locking? */
1311         for (f = 0; f < pkt->frames; f++) {
1312                 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1313                 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1314                 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1315                         BUG();
1316         }
1317         VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1318
1319         /*
1320          * Fill-in bvec with data from orig_bios.
1321          */
1322         spin_lock(&pkt->lock);
1323         bio_copy_data(pkt->w_bio, pkt->orig_bios.head);
1324
1325         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1326         spin_unlock(&pkt->lock);
1327
1328         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1329                 pkt->write_size, (unsigned long long)pkt->sector);
1330
1331         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1332                 pkt_make_local_copy(pkt, bvec);
1333                 pkt->cache_valid = 1;
1334         } else {
1335                 pkt->cache_valid = 0;
1336         }
1337
1338         /* Start the write request */
1339         atomic_set(&pkt->io_wait, 1);
1340         pkt->w_bio->bi_rw = WRITE;
1341         pkt_queue_bio(pd, pkt->w_bio);
1342 }
1343
1344 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1345 {
1346         struct bio *bio;
1347
1348         if (!uptodate)
1349                 pkt->cache_valid = 0;
1350
1351         /* Finish all bios corresponding to this packet */
1352         while ((bio = bio_list_pop(&pkt->orig_bios)))
1353                 bio_endio(bio, uptodate ? 0 : -EIO);
1354 }
1355
1356 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1357 {
1358         int uptodate;
1359
1360         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1361
1362         for (;;) {
1363                 switch (pkt->state) {
1364                 case PACKET_WAITING_STATE:
1365                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1366                                 return;
1367
1368                         pkt->sleep_time = 0;
1369                         pkt_gather_data(pd, pkt);
1370                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1371                         break;
1372
1373                 case PACKET_READ_WAIT_STATE:
1374                         if (atomic_read(&pkt->io_wait) > 0)
1375                                 return;
1376
1377                         if (atomic_read(&pkt->io_errors) > 0) {
1378                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1379                         } else {
1380                                 pkt_start_write(pd, pkt);
1381                         }
1382                         break;
1383
1384                 case PACKET_WRITE_WAIT_STATE:
1385                         if (atomic_read(&pkt->io_wait) > 0)
1386                                 return;
1387
1388                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1389                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1390                         } else {
1391                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1392                         }
1393                         break;
1394
1395                 case PACKET_RECOVERY_STATE:
1396                         if (pkt_start_recovery(pkt)) {
1397                                 pkt_start_write(pd, pkt);
1398                         } else {
1399                                 VPRINTK("No recovery possible\n");
1400                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1401                         }
1402                         break;
1403
1404                 case PACKET_FINISHED_STATE:
1405                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1406                         pkt_finish_packet(pkt, uptodate);
1407                         return;
1408
1409                 default:
1410                         BUG();
1411                         break;
1412                 }
1413         }
1414 }
1415
1416 static void pkt_handle_packets(struct pktcdvd_device *pd)
1417 {
1418         struct packet_data *pkt, *next;
1419
1420         VPRINTK("pkt_handle_packets\n");
1421
1422         /*
1423          * Run state machine for active packets
1424          */
1425         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1426                 if (atomic_read(&pkt->run_sm) > 0) {
1427                         atomic_set(&pkt->run_sm, 0);
1428                         pkt_run_state_machine(pd, pkt);
1429                 }
1430         }
1431
1432         /*
1433          * Move no longer active packets to the free list
1434          */
1435         spin_lock(&pd->cdrw.active_list_lock);
1436         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1437                 if (pkt->state == PACKET_FINISHED_STATE) {
1438                         list_del(&pkt->list);
1439                         pkt_put_packet_data(pd, pkt);
1440                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1441                         atomic_set(&pd->scan_queue, 1);
1442                 }
1443         }
1444         spin_unlock(&pd->cdrw.active_list_lock);
1445 }
1446
1447 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1448 {
1449         struct packet_data *pkt;
1450         int i;
1451
1452         for (i = 0; i < PACKET_NUM_STATES; i++)
1453                 states[i] = 0;
1454
1455         spin_lock(&pd->cdrw.active_list_lock);
1456         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1457                 states[pkt->state]++;
1458         }
1459         spin_unlock(&pd->cdrw.active_list_lock);
1460 }
1461
1462 /*
1463  * kcdrwd is woken up when writes have been queued for one of our
1464  * registered devices
1465  */
1466 static int kcdrwd(void *foobar)
1467 {
1468         struct pktcdvd_device *pd = foobar;
1469         struct packet_data *pkt;
1470         long min_sleep_time, residue;
1471
1472         set_user_nice(current, -20);
1473         set_freezable();
1474
1475         for (;;) {
1476                 DECLARE_WAITQUEUE(wait, current);
1477
1478                 /*
1479                  * Wait until there is something to do
1480                  */
1481                 add_wait_queue(&pd->wqueue, &wait);
1482                 for (;;) {
1483                         set_current_state(TASK_INTERRUPTIBLE);
1484
1485                         /* Check if we need to run pkt_handle_queue */
1486                         if (atomic_read(&pd->scan_queue) > 0)
1487                                 goto work_to_do;
1488
1489                         /* Check if we need to run the state machine for some packet */
1490                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1491                                 if (atomic_read(&pkt->run_sm) > 0)
1492                                         goto work_to_do;
1493                         }
1494
1495                         /* Check if we need to process the iosched queues */
1496                         if (atomic_read(&pd->iosched.attention) != 0)
1497                                 goto work_to_do;
1498
1499                         /* Otherwise, go to sleep */
1500                         if (PACKET_DEBUG > 1) {
1501                                 int states[PACKET_NUM_STATES];
1502                                 pkt_count_states(pd, states);
1503                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1504                                         states[0], states[1], states[2], states[3],
1505                                         states[4], states[5]);
1506                         }
1507
1508                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1509                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1510                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1511                                         min_sleep_time = pkt->sleep_time;
1512                         }
1513
1514                         VPRINTK("kcdrwd: sleeping\n");
1515                         residue = schedule_timeout(min_sleep_time);
1516                         VPRINTK("kcdrwd: wake up\n");
1517
1518                         /* make swsusp happy with our thread */
1519                         try_to_freeze();
1520
1521                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1522                                 if (!pkt->sleep_time)
1523                                         continue;
1524                                 pkt->sleep_time -= min_sleep_time - residue;
1525                                 if (pkt->sleep_time <= 0) {
1526                                         pkt->sleep_time = 0;
1527                                         atomic_inc(&pkt->run_sm);
1528                                 }
1529                         }
1530
1531                         if (kthread_should_stop())
1532                                 break;
1533                 }
1534 work_to_do:
1535                 set_current_state(TASK_RUNNING);
1536                 remove_wait_queue(&pd->wqueue, &wait);
1537
1538                 if (kthread_should_stop())
1539                         break;
1540
1541                 /*
1542                  * if pkt_handle_queue returns true, we can queue
1543                  * another request.
1544                  */
1545                 while (pkt_handle_queue(pd))
1546                         ;
1547
1548                 /*
1549                  * Handle packet state machine
1550                  */
1551                 pkt_handle_packets(pd);
1552
1553                 /*
1554                  * Handle iosched queues
1555                  */
1556                 pkt_iosched_process_queue(pd);
1557         }
1558
1559         return 0;
1560 }
1561
1562 static void pkt_print_settings(struct pktcdvd_device *pd)
1563 {
1564         pr_info("%s packets, %u blocks, Mode-%c disc\n",
1565                 pd->settings.fp ? "Fixed" : "Variable",
1566                 pd->settings.size >> 2,
1567                 pd->settings.block_mode == 8 ? '1' : '2');
1568 }
1569
1570 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1571 {
1572         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1573
1574         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1575         cgc->cmd[2] = page_code | (page_control << 6);
1576         cgc->cmd[7] = cgc->buflen >> 8;
1577         cgc->cmd[8] = cgc->buflen & 0xff;
1578         cgc->data_direction = CGC_DATA_READ;
1579         return pkt_generic_packet(pd, cgc);
1580 }
1581
1582 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1583 {
1584         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1585         memset(cgc->buffer, 0, 2);
1586         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1587         cgc->cmd[1] = 0x10;             /* PF */
1588         cgc->cmd[7] = cgc->buflen >> 8;
1589         cgc->cmd[8] = cgc->buflen & 0xff;
1590         cgc->data_direction = CGC_DATA_WRITE;
1591         return pkt_generic_packet(pd, cgc);
1592 }
1593
1594 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1595 {
1596         struct packet_command cgc;
1597         int ret;
1598
1599         /* set up command and get the disc info */
1600         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1601         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1602         cgc.cmd[8] = cgc.buflen = 2;
1603         cgc.quiet = 1;
1604
1605         if ((ret = pkt_generic_packet(pd, &cgc)))
1606                 return ret;
1607
1608         /* not all drives have the same disc_info length, so requeue
1609          * packet with the length the drive tells us it can supply
1610          */
1611         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1612                      sizeof(di->disc_information_length);
1613
1614         if (cgc.buflen > sizeof(disc_information))
1615                 cgc.buflen = sizeof(disc_information);
1616
1617         cgc.cmd[8] = cgc.buflen;
1618         return pkt_generic_packet(pd, &cgc);
1619 }
1620
1621 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1622 {
1623         struct packet_command cgc;
1624         int ret;
1625
1626         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1627         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1628         cgc.cmd[1] = type & 3;
1629         cgc.cmd[4] = (track & 0xff00) >> 8;
1630         cgc.cmd[5] = track & 0xff;
1631         cgc.cmd[8] = 8;
1632         cgc.quiet = 1;
1633
1634         if ((ret = pkt_generic_packet(pd, &cgc)))
1635                 return ret;
1636
1637         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1638                      sizeof(ti->track_information_length);
1639
1640         if (cgc.buflen > sizeof(track_information))
1641                 cgc.buflen = sizeof(track_information);
1642
1643         cgc.cmd[8] = cgc.buflen;
1644         return pkt_generic_packet(pd, &cgc);
1645 }
1646
1647 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1648                                                 long *last_written)
1649 {
1650         disc_information di;
1651         track_information ti;
1652         __u32 last_track;
1653         int ret = -1;
1654
1655         if ((ret = pkt_get_disc_info(pd, &di)))
1656                 return ret;
1657
1658         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1659         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1660                 return ret;
1661
1662         /* if this track is blank, try the previous. */
1663         if (ti.blank) {
1664                 last_track--;
1665                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1666                         return ret;
1667         }
1668
1669         /* if last recorded field is valid, return it. */
1670         if (ti.lra_v) {
1671                 *last_written = be32_to_cpu(ti.last_rec_address);
1672         } else {
1673                 /* make it up instead */
1674                 *last_written = be32_to_cpu(ti.track_start) +
1675                                 be32_to_cpu(ti.track_size);
1676                 if (ti.free_blocks)
1677                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1678         }
1679         return 0;
1680 }
1681
1682 /*
1683  * write mode select package based on pd->settings
1684  */
1685 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1686 {
1687         struct packet_command cgc;
1688         struct request_sense sense;
1689         write_param_page *wp;
1690         char buffer[128];
1691         int ret, size;
1692
1693         /* doesn't apply to DVD+RW or DVD-RAM */
1694         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1695                 return 0;
1696
1697         memset(buffer, 0, sizeof(buffer));
1698         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1699         cgc.sense = &sense;
1700         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1701                 pkt_dump_sense(&cgc);
1702                 return ret;
1703         }
1704
1705         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1706         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1707         if (size > sizeof(buffer))
1708                 size = sizeof(buffer);
1709
1710         /*
1711          * now get it all
1712          */
1713         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1714         cgc.sense = &sense;
1715         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1716                 pkt_dump_sense(&cgc);
1717                 return ret;
1718         }
1719
1720         /*
1721          * write page is offset header + block descriptor length
1722          */
1723         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1724
1725         wp->fp = pd->settings.fp;
1726         wp->track_mode = pd->settings.track_mode;
1727         wp->write_type = pd->settings.write_type;
1728         wp->data_block_type = pd->settings.block_mode;
1729
1730         wp->multi_session = 0;
1731
1732 #ifdef PACKET_USE_LS
1733         wp->link_size = 7;
1734         wp->ls_v = 1;
1735 #endif
1736
1737         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1738                 wp->session_format = 0;
1739                 wp->subhdr2 = 0x20;
1740         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1741                 wp->session_format = 0x20;
1742                 wp->subhdr2 = 8;
1743 #if 0
1744                 wp->mcn[0] = 0x80;
1745                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1746 #endif
1747         } else {
1748                 /*
1749                  * paranoia
1750                  */
1751                 pr_err("write mode wrong %d\n", wp->data_block_type);
1752                 return 1;
1753         }
1754         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1755
1756         cgc.buflen = cgc.cmd[8] = size;
1757         if ((ret = pkt_mode_select(pd, &cgc))) {
1758                 pkt_dump_sense(&cgc);
1759                 return ret;
1760         }
1761
1762         pkt_print_settings(pd);
1763         return 0;
1764 }
1765
1766 /*
1767  * 1 -- we can write to this track, 0 -- we can't
1768  */
1769 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1770 {
1771         switch (pd->mmc3_profile) {
1772                 case 0x1a: /* DVD+RW */
1773                 case 0x12: /* DVD-RAM */
1774                         /* The track is always writable on DVD+RW/DVD-RAM */
1775                         return 1;
1776                 default:
1777                         break;
1778         }
1779
1780         if (!ti->packet || !ti->fp)
1781                 return 0;
1782
1783         /*
1784          * "good" settings as per Mt Fuji.
1785          */
1786         if (ti->rt == 0 && ti->blank == 0)
1787                 return 1;
1788
1789         if (ti->rt == 0 && ti->blank == 1)
1790                 return 1;
1791
1792         if (ti->rt == 1 && ti->blank == 0)
1793                 return 1;
1794
1795         pr_err("bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1796         return 0;
1797 }
1798
1799 /*
1800  * 1 -- we can write to this disc, 0 -- we can't
1801  */
1802 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1803 {
1804         switch (pd->mmc3_profile) {
1805                 case 0x0a: /* CD-RW */
1806                 case 0xffff: /* MMC3 not supported */
1807                         break;
1808                 case 0x1a: /* DVD+RW */
1809                 case 0x13: /* DVD-RW */
1810                 case 0x12: /* DVD-RAM */
1811                         return 1;
1812                 default:
1813                         VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1814                         return 0;
1815         }
1816
1817         /*
1818          * for disc type 0xff we should probably reserve a new track.
1819          * but i'm not sure, should we leave this to user apps? probably.
1820          */
1821         if (di->disc_type == 0xff) {
1822                 pr_notice("unknown disc - no track?\n");
1823                 return 0;
1824         }
1825
1826         if (di->disc_type != 0x20 && di->disc_type != 0) {
1827                 pr_err("wrong disc type (%x)\n", di->disc_type);
1828                 return 0;
1829         }
1830
1831         if (di->erasable == 0) {
1832                 pr_notice("disc not erasable\n");
1833                 return 0;
1834         }
1835
1836         if (di->border_status == PACKET_SESSION_RESERVED) {
1837                 pr_err("can't write to last track (reserved)\n");
1838                 return 0;
1839         }
1840
1841         return 1;
1842 }
1843
1844 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1845 {
1846         struct packet_command cgc;
1847         unsigned char buf[12];
1848         disc_information di;
1849         track_information ti;
1850         int ret, track;
1851
1852         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1853         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1854         cgc.cmd[8] = 8;
1855         ret = pkt_generic_packet(pd, &cgc);
1856         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1857
1858         memset(&di, 0, sizeof(disc_information));
1859         memset(&ti, 0, sizeof(track_information));
1860
1861         if ((ret = pkt_get_disc_info(pd, &di))) {
1862                 pr_err("failed get_disc\n");
1863                 return ret;
1864         }
1865
1866         if (!pkt_writable_disc(pd, &di))
1867                 return -EROFS;
1868
1869         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1870
1871         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1872         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1873                 pr_err("failed get_track\n");
1874                 return ret;
1875         }
1876
1877         if (!pkt_writable_track(pd, &ti)) {
1878                 pr_err("can't write to this track\n");
1879                 return -EROFS;
1880         }
1881
1882         /*
1883          * we keep packet size in 512 byte units, makes it easier to
1884          * deal with request calculations.
1885          */
1886         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1887         if (pd->settings.size == 0) {
1888                 pr_notice("detected zero packet size!\n");
1889                 return -ENXIO;
1890         }
1891         if (pd->settings.size > PACKET_MAX_SECTORS) {
1892                 pr_err("packet size is too big\n");
1893                 return -EROFS;
1894         }
1895         pd->settings.fp = ti.fp;
1896         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1897
1898         if (ti.nwa_v) {
1899                 pd->nwa = be32_to_cpu(ti.next_writable);
1900                 set_bit(PACKET_NWA_VALID, &pd->flags);
1901         }
1902
1903         /*
1904          * in theory we could use lra on -RW media as well and just zero
1905          * blocks that haven't been written yet, but in practice that
1906          * is just a no-go. we'll use that for -R, naturally.
1907          */
1908         if (ti.lra_v) {
1909                 pd->lra = be32_to_cpu(ti.last_rec_address);
1910                 set_bit(PACKET_LRA_VALID, &pd->flags);
1911         } else {
1912                 pd->lra = 0xffffffff;
1913                 set_bit(PACKET_LRA_VALID, &pd->flags);
1914         }
1915
1916         /*
1917          * fine for now
1918          */
1919         pd->settings.link_loss = 7;
1920         pd->settings.write_type = 0;    /* packet */
1921         pd->settings.track_mode = ti.track_mode;
1922
1923         /*
1924          * mode1 or mode2 disc
1925          */
1926         switch (ti.data_mode) {
1927                 case PACKET_MODE1:
1928                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1929                         break;
1930                 case PACKET_MODE2:
1931                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1932                         break;
1933                 default:
1934                         pr_err("unknown data mode\n");
1935                         return -EROFS;
1936         }
1937         return 0;
1938 }
1939
1940 /*
1941  * enable/disable write caching on drive
1942  */
1943 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
1944                                                 int set)
1945 {
1946         struct packet_command cgc;
1947         struct request_sense sense;
1948         unsigned char buf[64];
1949         int ret;
1950
1951         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1952         cgc.sense = &sense;
1953         cgc.buflen = pd->mode_offset + 12;
1954
1955         /*
1956          * caching mode page might not be there, so quiet this command
1957          */
1958         cgc.quiet = 1;
1959
1960         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1961                 return ret;
1962
1963         buf[pd->mode_offset + 10] |= (!!set << 2);
1964
1965         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1966         ret = pkt_mode_select(pd, &cgc);
1967         if (ret) {
1968                 pr_err("write caching control failed\n");
1969                 pkt_dump_sense(&cgc);
1970         } else if (!ret && set)
1971                 pr_notice("enabled write caching on %s\n", pd->name);
1972         return ret;
1973 }
1974
1975 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1976 {
1977         struct packet_command cgc;
1978
1979         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1980         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1981         cgc.cmd[4] = lockflag ? 1 : 0;
1982         return pkt_generic_packet(pd, &cgc);
1983 }
1984
1985 /*
1986  * Returns drive maximum write speed
1987  */
1988 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1989                                                 unsigned *write_speed)
1990 {
1991         struct packet_command cgc;
1992         struct request_sense sense;
1993         unsigned char buf[256+18];
1994         unsigned char *cap_buf;
1995         int ret, offset;
1996
1997         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1998         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1999         cgc.sense = &sense;
2000
2001         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2002         if (ret) {
2003                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2004                              sizeof(struct mode_page_header);
2005                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2006                 if (ret) {
2007                         pkt_dump_sense(&cgc);
2008                         return ret;
2009                 }
2010         }
2011
2012         offset = 20;                        /* Obsoleted field, used by older drives */
2013         if (cap_buf[1] >= 28)
2014                 offset = 28;                /* Current write speed selected */
2015         if (cap_buf[1] >= 30) {
2016                 /* If the drive reports at least one "Logical Unit Write
2017                  * Speed Performance Descriptor Block", use the information
2018                  * in the first block. (contains the highest speed)
2019                  */
2020                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2021                 if (num_spdb > 0)
2022                         offset = 34;
2023         }
2024
2025         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2026         return 0;
2027 }
2028
2029 /* These tables from cdrecord - I don't have orange book */
2030 /* standard speed CD-RW (1-4x) */
2031 static char clv_to_speed[16] = {
2032         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2033            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2034 };
2035 /* high speed CD-RW (-10x) */
2036 static char hs_clv_to_speed[16] = {
2037         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2038            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2039 };
2040 /* ultra high speed CD-RW */
2041 static char us_clv_to_speed[16] = {
2042         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2043            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2044 };
2045
2046 /*
2047  * reads the maximum media speed from ATIP
2048  */
2049 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2050                                                 unsigned *speed)
2051 {
2052         struct packet_command cgc;
2053         struct request_sense sense;
2054         unsigned char buf[64];
2055         unsigned int size, st, sp;
2056         int ret;
2057
2058         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2059         cgc.sense = &sense;
2060         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2061         cgc.cmd[1] = 2;
2062         cgc.cmd[2] = 4; /* READ ATIP */
2063         cgc.cmd[8] = 2;
2064         ret = pkt_generic_packet(pd, &cgc);
2065         if (ret) {
2066                 pkt_dump_sense(&cgc);
2067                 return ret;
2068         }
2069         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2070         if (size > sizeof(buf))
2071                 size = sizeof(buf);
2072
2073         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2074         cgc.sense = &sense;
2075         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2076         cgc.cmd[1] = 2;
2077         cgc.cmd[2] = 4;
2078         cgc.cmd[8] = size;
2079         ret = pkt_generic_packet(pd, &cgc);
2080         if (ret) {
2081                 pkt_dump_sense(&cgc);
2082                 return ret;
2083         }
2084
2085         if (!(buf[6] & 0x40)) {
2086                 pr_notice("disc type is not CD-RW\n");
2087                 return 1;
2088         }
2089         if (!(buf[6] & 0x4)) {
2090                 pr_notice("A1 values on media are not valid, maybe not CDRW?\n");
2091                 return 1;
2092         }
2093
2094         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2095
2096         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2097
2098         /* Info from cdrecord */
2099         switch (st) {
2100                 case 0: /* standard speed */
2101                         *speed = clv_to_speed[sp];
2102                         break;
2103                 case 1: /* high speed */
2104                         *speed = hs_clv_to_speed[sp];
2105                         break;
2106                 case 2: /* ultra high speed */
2107                         *speed = us_clv_to_speed[sp];
2108                         break;
2109                 default:
2110                         pr_notice("unknown disc sub-type %d\n", st);
2111                         return 1;
2112         }
2113         if (*speed) {
2114                 pr_info("maximum media speed: %d\n", *speed);
2115                 return 0;
2116         } else {
2117                 pr_notice("unknown speed %d for sub-type %d\n", sp, st);
2118                 return 1;
2119         }
2120 }
2121
2122 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2123 {
2124         struct packet_command cgc;
2125         struct request_sense sense;
2126         int ret;
2127
2128         VPRINTK(DRIVER_NAME": Performing OPC\n");
2129
2130         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2131         cgc.sense = &sense;
2132         cgc.timeout = 60*HZ;
2133         cgc.cmd[0] = GPCMD_SEND_OPC;
2134         cgc.cmd[1] = 1;
2135         if ((ret = pkt_generic_packet(pd, &cgc)))
2136                 pkt_dump_sense(&cgc);
2137         return ret;
2138 }
2139
2140 static int pkt_open_write(struct pktcdvd_device *pd)
2141 {
2142         int ret;
2143         unsigned int write_speed, media_write_speed, read_speed;
2144
2145         if ((ret = pkt_probe_settings(pd))) {
2146                 VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2147                 return ret;
2148         }
2149
2150         if ((ret = pkt_set_write_settings(pd))) {
2151                 DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2152                 return -EIO;
2153         }
2154
2155         pkt_write_caching(pd, USE_WCACHING);
2156
2157         if ((ret = pkt_get_max_speed(pd, &write_speed)))
2158                 write_speed = 16 * 177;
2159         switch (pd->mmc3_profile) {
2160                 case 0x13: /* DVD-RW */
2161                 case 0x1a: /* DVD+RW */
2162                 case 0x12: /* DVD-RAM */
2163                         DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2164                         break;
2165                 default:
2166                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
2167                                 media_write_speed = 16;
2168                         write_speed = min(write_speed, media_write_speed * 177);
2169                         DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2170                         break;
2171         }
2172         read_speed = write_speed;
2173
2174         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2175                 DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2176                 return -EIO;
2177         }
2178         pd->write_speed = write_speed;
2179         pd->read_speed = read_speed;
2180
2181         if ((ret = pkt_perform_opc(pd))) {
2182                 DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2183         }
2184
2185         return 0;
2186 }
2187
2188 /*
2189  * called at open time.
2190  */
2191 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2192 {
2193         int ret;
2194         long lba;
2195         struct request_queue *q;
2196
2197         /*
2198          * We need to re-open the cdrom device without O_NONBLOCK to be able
2199          * to read/write from/to it. It is already opened in O_NONBLOCK mode
2200          * so bdget() can't fail.
2201          */
2202         bdget(pd->bdev->bd_dev);
2203         if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2204                 goto out;
2205
2206         if ((ret = pkt_get_last_written(pd, &lba))) {
2207                 pr_err("pkt_get_last_written failed\n");
2208                 goto out_putdev;
2209         }
2210
2211         set_capacity(pd->disk, lba << 2);
2212         set_capacity(pd->bdev->bd_disk, lba << 2);
2213         bd_set_size(pd->bdev, (loff_t)lba << 11);
2214
2215         q = bdev_get_queue(pd->bdev);
2216         if (write) {
2217                 if ((ret = pkt_open_write(pd)))
2218                         goto out_putdev;
2219                 /*
2220                  * Some CDRW drives can not handle writes larger than one packet,
2221                  * even if the size is a multiple of the packet size.
2222                  */
2223                 spin_lock_irq(q->queue_lock);
2224                 blk_queue_max_hw_sectors(q, pd->settings.size);
2225                 spin_unlock_irq(q->queue_lock);
2226                 set_bit(PACKET_WRITABLE, &pd->flags);
2227         } else {
2228                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2229                 clear_bit(PACKET_WRITABLE, &pd->flags);
2230         }
2231
2232         if ((ret = pkt_set_segment_merging(pd, q)))
2233                 goto out_putdev;
2234
2235         if (write) {
2236                 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2237                         pr_err("not enough memory for buffers\n");
2238                         ret = -ENOMEM;
2239                         goto out_putdev;
2240                 }
2241                 pr_info("%lukB available on disc\n", lba << 1);
2242         }
2243
2244         return 0;
2245
2246 out_putdev:
2247         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2248 out:
2249         return ret;
2250 }
2251
2252 /*
2253  * called when the device is closed. makes sure that the device flushes
2254  * the internal cache before we close.
2255  */
2256 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2257 {
2258         if (flush && pkt_flush_cache(pd))
2259                 DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2260
2261         pkt_lock_door(pd, 0);
2262
2263         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2264         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2265
2266         pkt_shrink_pktlist(pd);
2267 }
2268
2269 static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2270 {
2271         if (dev_minor >= MAX_WRITERS)
2272                 return NULL;
2273         return pkt_devs[dev_minor];
2274 }
2275
2276 static int pkt_open(struct block_device *bdev, fmode_t mode)
2277 {
2278         struct pktcdvd_device *pd = NULL;
2279         int ret;
2280
2281         VPRINTK(DRIVER_NAME": entering open\n");
2282
2283         mutex_lock(&pktcdvd_mutex);
2284         mutex_lock(&ctl_mutex);
2285         pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2286         if (!pd) {
2287                 ret = -ENODEV;
2288                 goto out;
2289         }
2290         BUG_ON(pd->refcnt < 0);
2291
2292         pd->refcnt++;
2293         if (pd->refcnt > 1) {
2294                 if ((mode & FMODE_WRITE) &&
2295                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2296                         ret = -EBUSY;
2297                         goto out_dec;
2298                 }
2299         } else {
2300                 ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2301                 if (ret)
2302                         goto out_dec;
2303                 /*
2304                  * needed here as well, since ext2 (among others) may change
2305                  * the blocksize at mount time
2306                  */
2307                 set_blocksize(bdev, CD_FRAMESIZE);
2308         }
2309
2310         mutex_unlock(&ctl_mutex);
2311         mutex_unlock(&pktcdvd_mutex);
2312         return 0;
2313
2314 out_dec:
2315         pd->refcnt--;
2316 out:
2317         VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2318         mutex_unlock(&ctl_mutex);
2319         mutex_unlock(&pktcdvd_mutex);
2320         return ret;
2321 }
2322
2323 static void pkt_close(struct gendisk *disk, fmode_t mode)
2324 {
2325         struct pktcdvd_device *pd = disk->private_data;
2326
2327         mutex_lock(&pktcdvd_mutex);
2328         mutex_lock(&ctl_mutex);
2329         pd->refcnt--;
2330         BUG_ON(pd->refcnt < 0);
2331         if (pd->refcnt == 0) {
2332                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2333                 pkt_release_dev(pd, flush);
2334         }
2335         mutex_unlock(&ctl_mutex);
2336         mutex_unlock(&pktcdvd_mutex);
2337 }
2338
2339
2340 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2341 {
2342         struct packet_stacked_data *psd = bio->bi_private;
2343         struct pktcdvd_device *pd = psd->pd;
2344
2345         bio_put(bio);
2346         bio_endio(psd->bio, err);
2347         mempool_free(psd, psd_pool);
2348         pkt_bio_finished(pd);
2349 }
2350
2351 static void pkt_make_request(struct request_queue *q, struct bio *bio)
2352 {
2353         struct pktcdvd_device *pd;
2354         char b[BDEVNAME_SIZE];
2355         sector_t zone;
2356         struct packet_data *pkt;
2357         int was_empty, blocked_bio;
2358         struct pkt_rb_node *node;
2359
2360         pd = q->queuedata;
2361         if (!pd) {
2362                 pr_err("%s incorrect request queue\n",
2363                        bdevname(bio->bi_bdev, b));
2364                 goto end_io;
2365         }
2366
2367         /*
2368          * Clone READ bios so we can have our own bi_end_io callback.
2369          */
2370         if (bio_data_dir(bio) == READ) {
2371                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2372                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2373
2374                 psd->pd = pd;
2375                 psd->bio = bio;
2376                 cloned_bio->bi_bdev = pd->bdev;
2377                 cloned_bio->bi_private = psd;
2378                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2379                 pd->stats.secs_r += bio_sectors(bio);
2380                 pkt_queue_bio(pd, cloned_bio);
2381                 return;
2382         }
2383
2384         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2385                 pr_notice("WRITE for ro device %s (%llu)\n",
2386                           pd->name, (unsigned long long)bio->bi_sector);
2387                 goto end_io;
2388         }
2389
2390         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2391                 pr_err("wrong bio size\n");
2392                 goto end_io;
2393         }
2394
2395         blk_queue_bounce(q, &bio);
2396
2397         zone = get_zone(bio->bi_sector, pd);
2398         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2399                 (unsigned long long)bio->bi_sector,
2400                 (unsigned long long)bio_end_sector(bio));
2401
2402         /* Check if we have to split the bio */
2403         {
2404                 struct bio_pair *bp;
2405                 sector_t last_zone;
2406                 int first_sectors;
2407
2408                 last_zone = get_zone(bio_end_sector(bio) - 1, pd);
2409                 if (last_zone != zone) {
2410                         BUG_ON(last_zone != zone + pd->settings.size);
2411                         first_sectors = last_zone - bio->bi_sector;
2412                         bp = bio_split(bio, first_sectors);
2413                         BUG_ON(!bp);
2414                         pkt_make_request(q, &bp->bio1);
2415                         pkt_make_request(q, &bp->bio2);
2416                         bio_pair_release(bp);
2417                         return;
2418                 }
2419         }
2420
2421         /*
2422          * If we find a matching packet in state WAITING or READ_WAIT, we can
2423          * just append this bio to that packet.
2424          */
2425         spin_lock(&pd->cdrw.active_list_lock);
2426         blocked_bio = 0;
2427         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2428                 if (pkt->sector == zone) {
2429                         spin_lock(&pkt->lock);
2430                         if ((pkt->state == PACKET_WAITING_STATE) ||
2431                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2432                                 bio_list_add(&pkt->orig_bios, bio);
2433                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2434                                 if ((pkt->write_size >= pkt->frames) &&
2435                                     (pkt->state == PACKET_WAITING_STATE)) {
2436                                         atomic_inc(&pkt->run_sm);
2437                                         wake_up(&pd->wqueue);
2438                                 }
2439                                 spin_unlock(&pkt->lock);
2440                                 spin_unlock(&pd->cdrw.active_list_lock);
2441                                 return;
2442                         } else {
2443                                 blocked_bio = 1;
2444                         }
2445                         spin_unlock(&pkt->lock);
2446                 }
2447         }
2448         spin_unlock(&pd->cdrw.active_list_lock);
2449
2450         /*
2451          * Test if there is enough room left in the bio work queue
2452          * (queue size >= congestion on mark).
2453          * If not, wait till the work queue size is below the congestion off mark.
2454          */
2455         spin_lock(&pd->lock);
2456         if (pd->write_congestion_on > 0
2457             && pd->bio_queue_size >= pd->write_congestion_on) {
2458                 set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2459                 do {
2460                         spin_unlock(&pd->lock);
2461                         congestion_wait(BLK_RW_ASYNC, HZ);
2462                         spin_lock(&pd->lock);
2463                 } while(pd->bio_queue_size > pd->write_congestion_off);
2464         }
2465         spin_unlock(&pd->lock);
2466
2467         /*
2468          * No matching packet found. Store the bio in the work queue.
2469          */
2470         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2471         node->bio = bio;
2472         spin_lock(&pd->lock);
2473         BUG_ON(pd->bio_queue_size < 0);
2474         was_empty = (pd->bio_queue_size == 0);
2475         pkt_rbtree_insert(pd, node);
2476         spin_unlock(&pd->lock);
2477
2478         /*
2479          * Wake up the worker thread.
2480          */
2481         atomic_set(&pd->scan_queue, 1);
2482         if (was_empty) {
2483                 /* This wake_up is required for correct operation */
2484                 wake_up(&pd->wqueue);
2485         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2486                 /*
2487                  * This wake up is not required for correct operation,
2488                  * but improves performance in some cases.
2489                  */
2490                 wake_up(&pd->wqueue);
2491         }
2492         return;
2493 end_io:
2494         bio_io_error(bio);
2495 }
2496
2497
2498
2499 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2500                           struct bio_vec *bvec)
2501 {
2502         struct pktcdvd_device *pd = q->queuedata;
2503         sector_t zone = get_zone(bmd->bi_sector, pd);
2504         int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2505         int remaining = (pd->settings.size << 9) - used;
2506         int remaining2;
2507
2508         /*
2509          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2510          * boundary, pkt_make_request() will split the bio.
2511          */
2512         remaining2 = PAGE_SIZE - bmd->bi_size;
2513         remaining = max(remaining, remaining2);
2514
2515         BUG_ON(remaining < 0);
2516         return remaining;
2517 }
2518
2519 static void pkt_init_queue(struct pktcdvd_device *pd)
2520 {
2521         struct request_queue *q = pd->disk->queue;
2522
2523         blk_queue_make_request(q, pkt_make_request);
2524         blk_queue_logical_block_size(q, CD_FRAMESIZE);
2525         blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2526         blk_queue_merge_bvec(q, pkt_merge_bvec);
2527         q->queuedata = pd;
2528 }
2529
2530 static int pkt_seq_show(struct seq_file *m, void *p)
2531 {
2532         struct pktcdvd_device *pd = m->private;
2533         char *msg;
2534         char bdev_buf[BDEVNAME_SIZE];
2535         int states[PACKET_NUM_STATES];
2536
2537         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2538                    bdevname(pd->bdev, bdev_buf));
2539
2540         seq_printf(m, "\nSettings:\n");
2541         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2542
2543         if (pd->settings.write_type == 0)
2544                 msg = "Packet";
2545         else
2546                 msg = "Unknown";
2547         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2548
2549         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2550         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2551
2552         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2553
2554         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2555                 msg = "Mode 1";
2556         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2557                 msg = "Mode 2";
2558         else
2559                 msg = "Unknown";
2560         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2561
2562         seq_printf(m, "\nStatistics:\n");
2563         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2564         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2565         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2566         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2567         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2568
2569         seq_printf(m, "\nMisc:\n");
2570         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2571         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2572         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2573         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2574         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2575         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2576
2577         seq_printf(m, "\nQueue state:\n");
2578         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2579         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2580         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2581
2582         pkt_count_states(pd, states);
2583         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2584                    states[0], states[1], states[2], states[3], states[4], states[5]);
2585
2586         seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2587                         pd->write_congestion_off,
2588                         pd->write_congestion_on);
2589         return 0;
2590 }
2591
2592 static int pkt_seq_open(struct inode *inode, struct file *file)
2593 {
2594         return single_open(file, pkt_seq_show, PDE_DATA(inode));
2595 }
2596
2597 static const struct file_operations pkt_proc_fops = {
2598         .open   = pkt_seq_open,
2599         .read   = seq_read,
2600         .llseek = seq_lseek,
2601         .release = single_release
2602 };
2603
2604 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2605 {
2606         int i;
2607         int ret = 0;
2608         char b[BDEVNAME_SIZE];
2609         struct block_device *bdev;
2610
2611         if (pd->pkt_dev == dev) {
2612                 pr_err("recursive setup not allowed\n");
2613                 return -EBUSY;
2614         }
2615         for (i = 0; i < MAX_WRITERS; i++) {
2616                 struct pktcdvd_device *pd2 = pkt_devs[i];
2617                 if (!pd2)
2618                         continue;
2619                 if (pd2->bdev->bd_dev == dev) {
2620                         pr_err("%s already setup\n", bdevname(pd2->bdev, b));
2621                         return -EBUSY;
2622                 }
2623                 if (pd2->pkt_dev == dev) {
2624                         pr_err("can't chain pktcdvd devices\n");
2625                         return -EBUSY;
2626                 }
2627         }
2628
2629         bdev = bdget(dev);
2630         if (!bdev)
2631                 return -ENOMEM;
2632         ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2633         if (ret)
2634                 return ret;
2635
2636         /* This is safe, since we have a reference from open(). */
2637         __module_get(THIS_MODULE);
2638
2639         pd->bdev = bdev;
2640         set_blocksize(bdev, CD_FRAMESIZE);
2641
2642         pkt_init_queue(pd);
2643
2644         atomic_set(&pd->cdrw.pending_bios, 0);
2645         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2646         if (IS_ERR(pd->cdrw.thread)) {
2647                 pr_err("can't start kernel thread\n");
2648                 ret = -ENOMEM;
2649                 goto out_mem;
2650         }
2651
2652         proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2653         DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2654         return 0;
2655
2656 out_mem:
2657         blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2658         /* This is safe: open() is still holding a reference. */
2659         module_put(THIS_MODULE);
2660         return ret;
2661 }
2662
2663 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2664 {
2665         struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2666         int ret;
2667
2668         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2669                 MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2670
2671         mutex_lock(&pktcdvd_mutex);
2672         switch (cmd) {
2673         case CDROMEJECT:
2674                 /*
2675                  * The door gets locked when the device is opened, so we
2676                  * have to unlock it or else the eject command fails.
2677                  */
2678                 if (pd->refcnt == 1)
2679                         pkt_lock_door(pd, 0);
2680                 /* fallthru */
2681         /*
2682          * forward selected CDROM ioctls to CD-ROM, for UDF
2683          */
2684         case CDROMMULTISESSION:
2685         case CDROMREADTOCENTRY:
2686         case CDROM_LAST_WRITTEN:
2687         case CDROM_SEND_PACKET:
2688         case SCSI_IOCTL_SEND_COMMAND:
2689                 ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2690                 break;
2691
2692         default:
2693                 VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2694                 ret = -ENOTTY;
2695         }
2696         mutex_unlock(&pktcdvd_mutex);
2697
2698         return ret;
2699 }
2700
2701 static unsigned int pkt_check_events(struct gendisk *disk,
2702                                      unsigned int clearing)
2703 {
2704         struct pktcdvd_device *pd = disk->private_data;
2705         struct gendisk *attached_disk;
2706
2707         if (!pd)
2708                 return 0;
2709         if (!pd->bdev)
2710                 return 0;
2711         attached_disk = pd->bdev->bd_disk;
2712         if (!attached_disk || !attached_disk->fops->check_events)
2713                 return 0;
2714         return attached_disk->fops->check_events(attached_disk, clearing);
2715 }
2716
2717 static const struct block_device_operations pktcdvd_ops = {
2718         .owner =                THIS_MODULE,
2719         .open =                 pkt_open,
2720         .release =              pkt_close,
2721         .ioctl =                pkt_ioctl,
2722         .check_events =         pkt_check_events,
2723 };
2724
2725 static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
2726 {
2727         return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2728 }
2729
2730 /*
2731  * Set up mapping from pktcdvd device to CD-ROM device.
2732  */
2733 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2734 {
2735         int idx;
2736         int ret = -ENOMEM;
2737         struct pktcdvd_device *pd;
2738         struct gendisk *disk;
2739
2740         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2741
2742         for (idx = 0; idx < MAX_WRITERS; idx++)
2743                 if (!pkt_devs[idx])
2744                         break;
2745         if (idx == MAX_WRITERS) {
2746                 pr_err("max %d writers supported\n", MAX_WRITERS);
2747                 ret = -EBUSY;
2748                 goto out_mutex;
2749         }
2750
2751         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2752         if (!pd)
2753                 goto out_mutex;
2754
2755         pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2756                                                   sizeof(struct pkt_rb_node));
2757         if (!pd->rb_pool)
2758                 goto out_mem;
2759
2760         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2761         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2762         spin_lock_init(&pd->cdrw.active_list_lock);
2763
2764         spin_lock_init(&pd->lock);
2765         spin_lock_init(&pd->iosched.lock);
2766         bio_list_init(&pd->iosched.read_queue);
2767         bio_list_init(&pd->iosched.write_queue);
2768         sprintf(pd->name, DRIVER_NAME"%d", idx);
2769         init_waitqueue_head(&pd->wqueue);
2770         pd->bio_queue = RB_ROOT;
2771
2772         pd->write_congestion_on  = write_congestion_on;
2773         pd->write_congestion_off = write_congestion_off;
2774
2775         disk = alloc_disk(1);
2776         if (!disk)
2777                 goto out_mem;
2778         pd->disk = disk;
2779         disk->major = pktdev_major;
2780         disk->first_minor = idx;
2781         disk->fops = &pktcdvd_ops;
2782         disk->flags = GENHD_FL_REMOVABLE;
2783         strcpy(disk->disk_name, pd->name);
2784         disk->devnode = pktcdvd_devnode;
2785         disk->private_data = pd;
2786         disk->queue = blk_alloc_queue(GFP_KERNEL);
2787         if (!disk->queue)
2788                 goto out_mem2;
2789
2790         pd->pkt_dev = MKDEV(pktdev_major, idx);
2791         ret = pkt_new_dev(pd, dev);
2792         if (ret)
2793                 goto out_new_dev;
2794
2795         /* inherit events of the host device */
2796         disk->events = pd->bdev->bd_disk->events;
2797         disk->async_events = pd->bdev->bd_disk->async_events;
2798
2799         add_disk(disk);
2800
2801         pkt_sysfs_dev_new(pd);
2802         pkt_debugfs_dev_new(pd);
2803
2804         pkt_devs[idx] = pd;
2805         if (pkt_dev)
2806                 *pkt_dev = pd->pkt_dev;
2807
2808         mutex_unlock(&ctl_mutex);
2809         return 0;
2810
2811 out_new_dev:
2812         blk_cleanup_queue(disk->queue);
2813 out_mem2:
2814         put_disk(disk);
2815 out_mem:
2816         if (pd->rb_pool)
2817                 mempool_destroy(pd->rb_pool);
2818         kfree(pd);
2819 out_mutex:
2820         mutex_unlock(&ctl_mutex);
2821         pr_err("setup of pktcdvd device failed\n");
2822         return ret;
2823 }
2824
2825 /*
2826  * Tear down mapping from pktcdvd device to CD-ROM device.
2827  */
2828 static int pkt_remove_dev(dev_t pkt_dev)
2829 {
2830         struct pktcdvd_device *pd;
2831         int idx;
2832         int ret = 0;
2833
2834         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2835
2836         for (idx = 0; idx < MAX_WRITERS; idx++) {
2837                 pd = pkt_devs[idx];
2838                 if (pd && (pd->pkt_dev == pkt_dev))
2839                         break;
2840         }
2841         if (idx == MAX_WRITERS) {
2842                 DPRINTK(DRIVER_NAME": dev not setup\n");
2843                 ret = -ENXIO;
2844                 goto out;
2845         }
2846
2847         if (pd->refcnt > 0) {
2848                 ret = -EBUSY;
2849                 goto out;
2850         }
2851         if (!IS_ERR(pd->cdrw.thread))
2852                 kthread_stop(pd->cdrw.thread);
2853
2854         pkt_devs[idx] = NULL;
2855
2856         pkt_debugfs_dev_remove(pd);
2857         pkt_sysfs_dev_remove(pd);
2858
2859         blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2860
2861         remove_proc_entry(pd->name, pkt_proc);
2862         DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2863
2864         del_gendisk(pd->disk);
2865         blk_cleanup_queue(pd->disk->queue);
2866         put_disk(pd->disk);
2867
2868         mempool_destroy(pd->rb_pool);
2869         kfree(pd);
2870
2871         /* This is safe: open() is still holding a reference. */
2872         module_put(THIS_MODULE);
2873
2874 out:
2875         mutex_unlock(&ctl_mutex);
2876         return ret;
2877 }
2878
2879 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2880 {
2881         struct pktcdvd_device *pd;
2882
2883         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2884
2885         pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2886         if (pd) {
2887                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2888                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2889         } else {
2890                 ctrl_cmd->dev = 0;
2891                 ctrl_cmd->pkt_dev = 0;
2892         }
2893         ctrl_cmd->num_devices = MAX_WRITERS;
2894
2895         mutex_unlock(&ctl_mutex);
2896 }
2897
2898 static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2899 {
2900         void __user *argp = (void __user *)arg;
2901         struct pkt_ctrl_command ctrl_cmd;
2902         int ret = 0;
2903         dev_t pkt_dev = 0;
2904
2905         if (cmd != PACKET_CTRL_CMD)
2906                 return -ENOTTY;
2907
2908         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2909                 return -EFAULT;
2910
2911         switch (ctrl_cmd.command) {
2912         case PKT_CTRL_CMD_SETUP:
2913                 if (!capable(CAP_SYS_ADMIN))
2914                         return -EPERM;
2915                 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2916                 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2917                 break;
2918         case PKT_CTRL_CMD_TEARDOWN:
2919                 if (!capable(CAP_SYS_ADMIN))
2920                         return -EPERM;
2921                 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2922                 break;
2923         case PKT_CTRL_CMD_STATUS:
2924                 pkt_get_status(&ctrl_cmd);
2925                 break;
2926         default:
2927                 return -ENOTTY;
2928         }
2929
2930         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2931                 return -EFAULT;
2932         return ret;
2933 }
2934
2935 #ifdef CONFIG_COMPAT
2936 static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2937 {
2938         return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2939 }
2940 #endif
2941
2942 static const struct file_operations pkt_ctl_fops = {
2943         .open           = nonseekable_open,
2944         .unlocked_ioctl = pkt_ctl_ioctl,
2945 #ifdef CONFIG_COMPAT
2946         .compat_ioctl   = pkt_ctl_compat_ioctl,
2947 #endif
2948         .owner          = THIS_MODULE,
2949         .llseek         = no_llseek,
2950 };
2951
2952 static struct miscdevice pkt_misc = {
2953         .minor          = MISC_DYNAMIC_MINOR,
2954         .name           = DRIVER_NAME,
2955         .nodename       = "pktcdvd/control",
2956         .fops           = &pkt_ctl_fops
2957 };
2958
2959 static int __init pkt_init(void)
2960 {
2961         int ret;
2962
2963         mutex_init(&ctl_mutex);
2964
2965         psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
2966                                         sizeof(struct packet_stacked_data));
2967         if (!psd_pool)
2968                 return -ENOMEM;
2969
2970         ret = register_blkdev(pktdev_major, DRIVER_NAME);
2971         if (ret < 0) {
2972                 pr_err("unable to register block device\n");
2973                 goto out2;
2974         }
2975         if (!pktdev_major)
2976                 pktdev_major = ret;
2977
2978         ret = pkt_sysfs_init();
2979         if (ret)
2980                 goto out;
2981
2982         pkt_debugfs_init();
2983
2984         ret = misc_register(&pkt_misc);
2985         if (ret) {
2986                 pr_err("unable to register misc device\n");
2987                 goto out_misc;
2988         }
2989
2990         pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
2991
2992         return 0;
2993
2994 out_misc:
2995         pkt_debugfs_cleanup();
2996         pkt_sysfs_cleanup();
2997 out:
2998         unregister_blkdev(pktdev_major, DRIVER_NAME);
2999 out2:
3000         mempool_destroy(psd_pool);
3001         return ret;
3002 }
3003
3004 static void __exit pkt_exit(void)
3005 {
3006         remove_proc_entry("driver/"DRIVER_NAME, NULL);
3007         misc_deregister(&pkt_misc);
3008
3009         pkt_debugfs_cleanup();
3010         pkt_sysfs_cleanup();
3011
3012         unregister_blkdev(pktdev_major, DRIVER_NAME);
3013         mempool_destroy(psd_pool);
3014 }
3015
3016 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3017 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3018 MODULE_LICENSE("GPL");
3019
3020 module_init(pkt_init);
3021 module_exit(pkt_exit);