git.oblomov.eu Git - linux-2.6/blob - 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  *
   5  * May be copied or modified under the terms of the GNU General Public
   6  * License.  See linux/COPYING for more information.
   7  *
   8  * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
   9  * DVD-RAM devices.
  10  *
  11  * Theory of operation:
  12  *
  13  * At the lowest level, there is the standard driver for the CD/DVD device,
  14  * typically ide-cd.c or sr.c. This driver can handle read and write requests,
  15  * but it doesn't know anything about the special restrictions that apply to
  16  * packet writing. One restriction is that write requests must be aligned to
  17  * packet boundaries on the physical media, and the size of a write request
  18  * must be equal to the packet size. Another restriction is that a
  19  * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
  20  * command, if the previous command was a write.
  21  *
  22  * The purpose of the packet writing driver is to hide these restrictions from
  23  * higher layers, such as file systems, and present a block device that can be
  24  * randomly read and written using 2kB-sized blocks.
  25  *
  26  * The lowest layer in the packet writing driver is the packet I/O scheduler.
  27  * Its data is defined by the struct packet_iosched and includes two bio
  28  * queues with pending read and write requests. These queues are processed
  29  * by the pkt_iosched_process_queue() function. The write requests in this
  30  * queue are already properly aligned and sized. This layer is responsible for
  31  * issuing the flush cache commands and scheduling the I/O in a good order.
  32  *
  33  * The next layer transforms unaligned write requests to aligned writes. This
  34  * transformation requires reading missing pieces of data from the underlying
  35  * block device, assembling the pieces to full packets and queuing them to the
  36  * packet I/O scheduler.
  37  *
  38  * At the top layer there is a custom make_request_fn function that forwards
  39  * read requests directly to the iosched queue and puts write requests in the
  40  * unaligned write queue. A kernel thread performs the necessary read
  41  * gathering to convert the unaligned writes to aligned writes and then feeds
  42  * them to the packet I/O scheduler.
  43  *
  44  *************************************************************************/
  45
  46 #include <linux/pktcdvd.h>
  47 #include <linux/config.h>
  48 #include <linux/module.h>
  49 #include <linux/types.h>
  50 #include <linux/kernel.h>
  51 #include <linux/kthread.h>
  52 #include <linux/errno.h>
  53 #include <linux/spinlock.h>
  54 #include <linux/file.h>
  55 #include <linux/proc_fs.h>
  56 #include <linux/seq_file.h>
  57 #include <linux/miscdevice.h>
  58 #include <linux/suspend.h>
  59 #include <linux/mutex.h>
  60 #include <scsi/scsi_cmnd.h>
  61 #include <scsi/scsi_ioctl.h>
  62 #include <scsi/scsi.h>
  63
  64 #include <asm/uaccess.h>
  65
  66 #if PACKET_DEBUG
  67 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  68 #else
  69 #define DPRINTK(fmt, args...)
  70 #endif
  71
  72 #if PACKET_DEBUG > 1
  73 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  74 #else
  75 #define VPRINTK(fmt, args...)
  76 #endif
  77
  78 #define MAX_SPEED 0xffff
  79
  80 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  81
  82 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  83 static struct proc_dir_entry *pkt_proc;
  84 static int pkt_major;
  85 static struct mutex ctl_mutex;  /* Serialize open/close/setup/teardown */
  86 static mempool_t *psd_pool;
  87
  88
  89 static void pkt_bio_finished(struct pktcdvd_device *pd)
  90 {
  91         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
  92         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
  93                 VPRINTK("pktcdvd: queue empty\n");
  94                 atomic_set(&pd->iosched.attention, 1);
  95                 wake_up(&pd->wqueue);
  96         }
  97 }
  98
  99 static void pkt_bio_destructor(struct bio *bio)
 100 {
 101         kfree(bio->bi_io_vec);
 102         kfree(bio);
 103 }
 104
 105 static struct bio *pkt_bio_alloc(int nr_iovecs)
 106 {
 107         struct bio_vec *bvl = NULL;
 108         struct bio *bio;
 109
 110         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
 111         if (!bio)
 112                 goto no_bio;
 113         bio_init(bio);
 114
 115         bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL);
 116         if (!bvl)
 117                 goto no_bvl;
 118
 119         bio->bi_max_vecs = nr_iovecs;
 120         bio->bi_io_vec = bvl;
 121         bio->bi_destructor = pkt_bio_destructor;
 122
 123         return bio;
 124
 125  no_bvl:
 126         kfree(bio);
 127  no_bio:
 128         return NULL;
 129 }
 130
 131 /*
 132  * Allocate a packet_data struct
 133  */
 134 static struct packet_data *pkt_alloc_packet_data(int frames)
 135 {
 136         int i;
 137         struct packet_data *pkt;
 138
 139         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 140         if (!pkt)
 141                 goto no_pkt;
 142
 143         pkt->frames = frames;
 144         pkt->w_bio = pkt_bio_alloc(frames);
 145         if (!pkt->w_bio)
 146                 goto no_bio;
 147
 148         for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 149                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 150                 if (!pkt->pages[i])
 151                         goto no_page;
 152         }
 153
 154         spin_lock_init(&pkt->lock);
 155
 156         for (i = 0; i < frames; i++) {
 157                 struct bio *bio = pkt_bio_alloc(1);
 158                 if (!bio)
 159                         goto no_rd_bio;
 160                 pkt->r_bios[i] = bio;
 161         }
 162
 163         return pkt;
 164
 165 no_rd_bio:
 166         for (i = 0; i < frames; i++) {
 167                 struct bio *bio = pkt->r_bios[i];
 168                 if (bio)
 169                         bio_put(bio);
 170         }
 171
 172 no_page:
 173         for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 174                 if (pkt->pages[i])
 175                         __free_page(pkt->pages[i]);
 176         bio_put(pkt->w_bio);
 177 no_bio:
 178         kfree(pkt);
 179 no_pkt:
 180         return NULL;
 181 }
 182
 183 /*
 184  * Free a packet_data struct
 185  */
 186 static void pkt_free_packet_data(struct packet_data *pkt)
 187 {
 188         int i;
 189
 190         for (i = 0; i < pkt->frames; i++) {
 191                 struct bio *bio = pkt->r_bios[i];
 192                 if (bio)
 193                         bio_put(bio);
 194         }
 195         for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 196                 __free_page(pkt->pages[i]);
 197         bio_put(pkt->w_bio);
 198         kfree(pkt);
 199 }
 200
 201 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 202 {
 203         struct packet_data *pkt, *next;
 204
 205         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 206
 207         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 208                 pkt_free_packet_data(pkt);
 209         }
 210         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 211 }
 212
 213 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 214 {
 215         struct packet_data *pkt;
 216
 217         BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 218
 219         while (nr_packets > 0) {
 220                 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 221                 if (!pkt) {
 222                         pkt_shrink_pktlist(pd);
 223                         return 0;
 224                 }
 225                 pkt->id = nr_packets;
 226                 pkt->pd = pd;
 227                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 228                 nr_packets--;
 229         }
 230         return 1;
 231 }
 232
 233 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 234 {
 235         struct rb_node *n = rb_next(&node->rb_node);
 236         if (!n)
 237                 return NULL;
 238         return rb_entry(n, struct pkt_rb_node, rb_node);
 239 }
 240
 241 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 242 {
 243         rb_erase(&node->rb_node, &pd->bio_queue);
 244         mempool_free(node, pd->rb_pool);
 245         pd->bio_queue_size--;
 246         BUG_ON(pd->bio_queue_size < 0);
 247 }
 248
 249 /*
 250  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 251  */
 252 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 253 {
 254         struct rb_node *n = pd->bio_queue.rb_node;
 255         struct rb_node *next;
 256         struct pkt_rb_node *tmp;
 257
 258         if (!n) {
 259                 BUG_ON(pd->bio_queue_size > 0);
 260                 return NULL;
 261         }
 262
 263         for (;;) {
 264                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 265                 if (s <= tmp->bio->bi_sector)
 266                         next = n->rb_left;
 267                 else
 268                         next = n->rb_right;
 269                 if (!next)
 270                         break;
 271                 n = next;
 272         }
 273
 274         if (s > tmp->bio->bi_sector) {
 275                 tmp = pkt_rbtree_next(tmp);
 276                 if (!tmp)
 277                         return NULL;
 278         }
 279         BUG_ON(s > tmp->bio->bi_sector);
 280         return tmp;
 281 }
 282
 283 /*
 284  * Insert a node into the pd->bio_queue rb tree.
 285  */
 286 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 287 {
 288         struct rb_node **p = &pd->bio_queue.rb_node;
 289         struct rb_node *parent = NULL;
 290         sector_t s = node->bio->bi_sector;
 291         struct pkt_rb_node *tmp;
 292
 293         while (*p) {
 294                 parent = *p;
 295                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 296                 if (s < tmp->bio->bi_sector)
 297                         p = &(*p)->rb_left;
 298                 else
 299                         p = &(*p)->rb_right;
 300         }
 301         rb_link_node(&node->rb_node, parent, p);
 302         rb_insert_color(&node->rb_node, &pd->bio_queue);
 303         pd->bio_queue_size++;
 304 }
 305
 306 /*
 307  * Add a bio to a single linked list defined by its head and tail pointers.
 308  */
 309 static void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
 310 {
 311         bio->bi_next = NULL;
 312         if (*list_tail) {
 313                 BUG_ON((*list_head) == NULL);
 314                 (*list_tail)->bi_next = bio;
 315                 (*list_tail) = bio;
 316         } else {
 317                 BUG_ON((*list_head) != NULL);
 318                 (*list_head) = bio;
 319                 (*list_tail) = bio;
 320         }
 321 }
 322
 323 /*
 324  * Remove and return the first bio from a single linked list defined by its
 325  * head and tail pointers.
 326  */
 327 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
 328 {
 329         struct bio *bio;
 330
 331         if (*list_head == NULL)
 332                 return NULL;
 333
 334         bio = *list_head;
 335         *list_head = bio->bi_next;
 336         if (*list_head == NULL)
 337                 *list_tail = NULL;
 338
 339         bio->bi_next = NULL;
 340         return bio;
 341 }
 342
 343 /*
 344  * Send a packet_command to the underlying block device and
 345  * wait for completion.
 346  */
 347 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 348 {
 349         char sense[SCSI_SENSE_BUFFERSIZE];
 350         request_queue_t *q;
 351         struct request *rq;
 352         DECLARE_COMPLETION(wait);
 353         int err = 0;
 354
 355         q = bdev_get_queue(pd->bdev);
 356
 357         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ,
 358                              __GFP_WAIT);
 359         rq->errors = 0;
 360         rq->rq_disk = pd->bdev->bd_disk;
 361         rq->bio = NULL;
 362         rq->buffer = NULL;
 363         rq->timeout = 60*HZ;
 364         rq->data = cgc->buffer;
 365         rq->data_len = cgc->buflen;
 366         rq->sense = sense;
 367         memset(sense, 0, sizeof(sense));
 368         rq->sense_len = 0;
 369         rq->flags |= REQ_BLOCK_PC | REQ_HARDBARRIER;
 370         if (cgc->quiet)
 371                 rq->flags |= REQ_QUIET;
 372         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 373         if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
 374                 memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);
 375         rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
 376
 377         rq->ref_count++;
 378         rq->flags |= REQ_NOMERGE;
 379         rq->waiting = &wait;
 380         rq->end_io = blk_end_sync_rq;
 381         elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
 382         generic_unplug_device(q);
 383         wait_for_completion(&wait);
 384
 385         if (rq->errors)
 386                 err = -EIO;
 387
 388         blk_put_request(rq);
 389         return err;
 390 }
 391
 392 /*
 393  * A generic sense dump / resolve mechanism should be implemented across
 394  * all ATAPI + SCSI devices.
 395  */
 396 static void pkt_dump_sense(struct packet_command *cgc)
 397 {
 398         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 399                                  "Medium error", "Hardware error", "Illegal request",
 400                                  "Unit attention", "Data protect", "Blank check" };
 401         int i;
 402         struct request_sense *sense = cgc->sense;
 403
 404         printk("pktcdvd:");
 405         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 406                 printk(" %02x", cgc->cmd[i]);
 407         printk(" - ");
 408
 409         if (sense == NULL) {
 410                 printk("no sense\n");
 411                 return;
 412         }
 413
 414         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 415
 416         if (sense->sense_key > 8) {
 417                 printk(" (INVALID)\n");
 418                 return;
 419         }
 420
 421         printk(" (%s)\n", info[sense->sense_key]);
 422 }
 423
 424 /*
 425  * flush the drive cache to media
 426  */
 427 static int pkt_flush_cache(struct pktcdvd_device *pd)
 428 {
 429         struct packet_command cgc;
 430
 431         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 432         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 433         cgc.quiet = 1;
 434
 435         /*
 436          * the IMMED bit -- we default to not setting it, although that
 437          * would allow a much faster close, this is safer
 438          */
 439 #if 0
 440         cgc.cmd[1] = 1 << 1;
 441 #endif
 442         return pkt_generic_packet(pd, &cgc);
 443 }
 444
 445 /*
 446  * speed is given as the normal factor, e.g. 4 for 4x
 447  */
 448 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
 449 {
 450         struct packet_command cgc;
 451         struct request_sense sense;
 452         int ret;
 453
 454         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 455         cgc.sense = &sense;
 456         cgc.cmd[0] = GPCMD_SET_SPEED;
 457         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 458         cgc.cmd[3] = read_speed & 0xff;
 459         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 460         cgc.cmd[5] = write_speed & 0xff;
 461
 462         if ((ret = pkt_generic_packet(pd, &cgc)))
 463                 pkt_dump_sense(&cgc);
 464
 465         return ret;
 466 }
 467
 468 /*
 469  * Queue a bio for processing by the low-level CD device. Must be called
 470  * from process context.
 471  */
 472 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 473 {
 474         spin_lock(&pd->iosched.lock);
 475         if (bio_data_dir(bio) == READ) {
 476                 pkt_add_list_last(bio, &pd->iosched.read_queue,
 477                                   &pd->iosched.read_queue_tail);
 478         } else {
 479                 pkt_add_list_last(bio, &pd->iosched.write_queue,
 480                                   &pd->iosched.write_queue_tail);
 481         }
 482         spin_unlock(&pd->iosched.lock);
 483
 484         atomic_set(&pd->iosched.attention, 1);
 485         wake_up(&pd->wqueue);
 486 }
 487
 488 /*
 489  * Process the queued read/write requests. This function handles special
 490  * requirements for CDRW drives:
 491  * - A cache flush command must be inserted before a read request if the
 492  *   previous request was a write.
 493  * - Switching between reading and writing is slow, so don't do it more often
 494  *   than necessary.
 495  * - Optimize for throughput at the expense of latency. This means that streaming
 496  *   writes will never be interrupted by a read, but if the drive has to seek
 497  *   before the next write, switch to reading instead if there are any pending
 498  *   read requests.
 499  * - Set the read speed according to current usage pattern. When only reading
 500  *   from the device, it's best to use the highest possible read speed, but
 501  *   when switching often between reading and writing, it's better to have the
 502  *   same read and write speeds.
 503  */
 504 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 505 {
 506
 507         if (atomic_read(&pd->iosched.attention) == 0)
 508                 return;
 509         atomic_set(&pd->iosched.attention, 0);
 510
 511         for (;;) {
 512                 struct bio *bio;
 513                 int reads_queued, writes_queued;
 514
 515                 spin_lock(&pd->iosched.lock);
 516                 reads_queued = (pd->iosched.read_queue != NULL);
 517                 writes_queued = (pd->iosched.write_queue != NULL);
 518                 spin_unlock(&pd->iosched.lock);
 519
 520                 if (!reads_queued && !writes_queued)
 521                         break;
 522
 523                 if (pd->iosched.writing) {
 524                         int need_write_seek = 1;
 525                         spin_lock(&pd->iosched.lock);
 526                         bio = pd->iosched.write_queue;
 527                         spin_unlock(&pd->iosched.lock);
 528                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 529                                 need_write_seek = 0;
 530                         if (need_write_seek && reads_queued) {
 531                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 532                                         VPRINTK("pktcdvd: write, waiting\n");
 533                                         break;
 534                                 }
 535                                 pkt_flush_cache(pd);
 536                                 pd->iosched.writing = 0;
 537                         }
 538                 } else {
 539                         if (!reads_queued && writes_queued) {
 540                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 541                                         VPRINTK("pktcdvd: read, waiting\n");
 542                                         break;
 543                                 }
 544                                 pd->iosched.writing = 1;
 545                         }
 546                 }
 547
 548                 spin_lock(&pd->iosched.lock);
 549                 if (pd->iosched.writing) {
 550                         bio = pkt_get_list_first(&pd->iosched.write_queue,
 551                                                  &pd->iosched.write_queue_tail);
 552                 } else {
 553                         bio = pkt_get_list_first(&pd->iosched.read_queue,
 554                                                  &pd->iosched.read_queue_tail);
 555                 }
 556                 spin_unlock(&pd->iosched.lock);
 557
 558                 if (!bio)
 559                         continue;
 560
 561                 if (bio_data_dir(bio) == READ)
 562                         pd->iosched.successive_reads += bio->bi_size >> 10;
 563                 else {
 564                         pd->iosched.successive_reads = 0;
 565                         pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
 566                 }
 567                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 568                         if (pd->read_speed == pd->write_speed) {
 569                                 pd->read_speed = MAX_SPEED;
 570                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 571                         }
 572                 } else {
 573                         if (pd->read_speed != pd->write_speed) {
 574                                 pd->read_speed = pd->write_speed;
 575                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 576                         }
 577                 }
 578
 579                 atomic_inc(&pd->cdrw.pending_bios);
 580                 generic_make_request(bio);
 581         }
 582 }
 583
 584 /*
 585  * Special care is needed if the underlying block device has a small
 586  * max_phys_segments value.
 587  */
 588 static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
 589 {
 590         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 591                 /*
 592                  * The cdrom device can handle one segment/frame
 593                  */
 594                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 595                 return 0;
 596         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
 597                 /*
 598                  * We can handle this case at the expense of some extra memory
 599                  * copies during write operations
 600                  */
 601                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 602                 return 0;
 603         } else {
 604                 printk("pktcdvd: cdrom max_phys_segments too small\n");
 605                 return -EIO;
 606         }
 607 }
 608
 609 /*
 610  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 611  */
 612 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 613 {
 614         unsigned int copy_size = CD_FRAMESIZE;
 615
 616         while (copy_size > 0) {
 617                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 618                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 619                         src_bvl->bv_offset + offs;
 620                 void *vto = page_address(dst_page) + dst_offs;
 621                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 622
 623                 BUG_ON(len < 0);
 624                 memcpy(vto, vfrom, len);
 625                 kunmap_atomic(vfrom, KM_USER0);
 626
 627                 seg++;
 628                 offs = 0;
 629                 dst_offs += len;
 630                 copy_size -= len;
 631         }
 632 }
 633
 634 /*
 635  * Copy all data for this packet to pkt->pages[], so that
 636  * a) The number of required segments for the write bio is minimized, which
 637  *    is necessary for some scsi controllers.
 638  * b) The data can be used as cache to avoid read requests if we receive a
 639  *    new write request for the same zone.
 640  */
 641 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
 642 {
 643         int f, p, offs;
 644
 645         /* Copy all data to pkt->pages[] */
 646         p = 0;
 647         offs = 0;
 648         for (f = 0; f < pkt->frames; f++) {
 649                 if (bvec[f].bv_page != pkt->pages[p]) {
 650                         void *vfrom = kmap_atomic(bvec[f].bv_page, KM_USER0) + bvec[f].bv_offset;
 651                         void *vto = page_address(pkt->pages[p]) + offs;
 652                         memcpy(vto, vfrom, CD_FRAMESIZE);
 653                         kunmap_atomic(vfrom, KM_USER0);
 654                         bvec[f].bv_page = pkt->pages[p];
 655                         bvec[f].bv_offset = offs;
 656                 } else {
 657                         BUG_ON(bvec[f].bv_offset != offs);
 658                 }
 659                 offs += CD_FRAMESIZE;
 660                 if (offs >= PAGE_SIZE) {
 661                         offs = 0;
 662                         p++;
 663                 }
 664         }
 665 }
 666
 667 static int pkt_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
 668 {
 669         struct packet_data *pkt = bio->bi_private;
 670         struct pktcdvd_device *pd = pkt->pd;
 671         BUG_ON(!pd);
 672
 673         if (bio->bi_size)
 674                 return 1;
 675
 676         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 677                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 678
 679         if (err)
 680                 atomic_inc(&pkt->io_errors);
 681         if (atomic_dec_and_test(&pkt->io_wait)) {
 682                 atomic_inc(&pkt->run_sm);
 683                 wake_up(&pd->wqueue);
 684         }
 685         pkt_bio_finished(pd);
 686
 687         return 0;
 688 }
 689
 690 static int pkt_end_io_packet_write(struct bio *bio, unsigned int bytes_done, int err)
 691 {
 692         struct packet_data *pkt = bio->bi_private;
 693         struct pktcdvd_device *pd = pkt->pd;
 694         BUG_ON(!pd);
 695
 696         if (bio->bi_size)
 697                 return 1;
 698
 699         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
 700
 701         pd->stats.pkt_ended++;
 702
 703         pkt_bio_finished(pd);
 704         atomic_dec(&pkt->io_wait);
 705         atomic_inc(&pkt->run_sm);
 706         wake_up(&pd->wqueue);
 707         return 0;
 708 }
 709
 710 /*
 711  * Schedule reads for the holes in a packet
 712  */
 713 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 714 {
 715         int frames_read = 0;
 716         struct bio *bio;
 717         int f;
 718         char written[PACKET_MAX_SIZE];
 719
 720         BUG_ON(!pkt->orig_bios);
 721
 722         atomic_set(&pkt->io_wait, 0);
 723         atomic_set(&pkt->io_errors, 0);
 724
 725         /*
 726          * Figure out which frames we need to read before we can write.
 727          */
 728         memset(written, 0, sizeof(written));
 729         spin_lock(&pkt->lock);
 730         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
 731                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
 732                 int num_frames = bio->bi_size / CD_FRAMESIZE;
 733                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
 734                 BUG_ON(first_frame < 0);
 735                 BUG_ON(first_frame + num_frames > pkt->frames);
 736                 for (f = first_frame; f < first_frame + num_frames; f++)
 737                         written[f] = 1;
 738         }
 739         spin_unlock(&pkt->lock);
 740
 741         if (pkt->cache_valid) {
 742                 VPRINTK("pkt_gather_data: zone %llx cached\n",
 743                         (unsigned long long)pkt->sector);
 744                 goto out_account;
 745         }
 746
 747         /*
 748          * Schedule reads for missing parts of the packet.
 749          */
 750         for (f = 0; f < pkt->frames; f++) {
 751                 int p, offset;
 752                 if (written[f])
 753                         continue;
 754                 bio = pkt->r_bios[f];
 755                 bio_init(bio);
 756                 bio->bi_max_vecs = 1;
 757                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 758                 bio->bi_bdev = pd->bdev;
 759                 bio->bi_end_io = pkt_end_io_read;
 760                 bio->bi_private = pkt;
 761
 762                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
 763                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 764                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
 765                         f, pkt->pages[p], offset);
 766                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
 767                         BUG();
 768
 769                 atomic_inc(&pkt->io_wait);
 770                 bio->bi_rw = READ;
 771                 pkt_queue_bio(pd, bio);
 772                 frames_read++;
 773         }
 774
 775 out_account:
 776         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
 777                 frames_read, (unsigned long long)pkt->sector);
 778         pd->stats.pkt_started++;
 779         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
 780 }
 781
 782 /*
 783  * Find a packet matching zone, or the least recently used packet if
 784  * there is no match.
 785  */
 786 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
 787 {
 788         struct packet_data *pkt;
 789
 790         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
 791                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
 792                         list_del_init(&pkt->list);
 793                         if (pkt->sector != zone)
 794                                 pkt->cache_valid = 0;
 795                         return pkt;
 796                 }
 797         }
 798         BUG();
 799         return NULL;
 800 }
 801
 802 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 803 {
 804         if (pkt->cache_valid) {
 805                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 806         } else {
 807                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
 808         }
 809 }
 810
 811 /*
 812  * recover a failed write, query for relocation if possible
 813  *
 814  * returns 1 if recovery is possible, or 0 if not
 815  *
 816  */
 817 static int pkt_start_recovery(struct packet_data *pkt)
 818 {
 819         /*
 820          * FIXME. We need help from the file system to implement
 821          * recovery handling.
 822          */
 823         return 0;
 824 #if 0
 825         struct request *rq = pkt->rq;
 826         struct pktcdvd_device *pd = rq->rq_disk->private_data;
 827         struct block_device *pkt_bdev;
 828         struct super_block *sb = NULL;
 829         unsigned long old_block, new_block;
 830         sector_t new_sector;
 831
 832         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
 833         if (pkt_bdev) {
 834                 sb = get_super(pkt_bdev);
 835                 bdput(pkt_bdev);
 836         }
 837
 838         if (!sb)
 839                 return 0;
 840
 841         if (!sb->s_op || !sb->s_op->relocate_blocks)
 842                 goto out;
 843
 844         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
 845         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
 846                 goto out;
 847
 848         new_sector = new_block * (CD_FRAMESIZE >> 9);
 849         pkt->sector = new_sector;
 850
 851         pkt->bio->bi_sector = new_sector;
 852         pkt->bio->bi_next = NULL;
 853         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
 854         pkt->bio->bi_idx = 0;
 855
 856         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
 857         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
 858         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
 859         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
 860         BUG_ON(pkt->bio->bi_private != pkt);
 861
 862         drop_super(sb);
 863         return 1;
 864
 865 out:
 866         drop_super(sb);
 867         return 0;
 868 #endif
 869 }
 870
 871 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
 872 {
 873 #if PACKET_DEBUG > 1
 874         static const char *state_name[] = {
 875                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
 876         };
 877         enum packet_data_state old_state = pkt->state;
 878         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
 879                 state_name[old_state], state_name[state]);
 880 #endif
 881         pkt->state = state;
 882 }
 883
 884 /*
 885  * Scan the work queue to see if we can start a new packet.
 886  * returns non-zero if any work was done.
 887  */
 888 static int pkt_handle_queue(struct pktcdvd_device *pd)
 889 {
 890         struct packet_data *pkt, *p;
 891         struct bio *bio = NULL;
 892         sector_t zone = 0; /* Suppress gcc warning */
 893         struct pkt_rb_node *node, *first_node;
 894         struct rb_node *n;
 895
 896         VPRINTK("handle_queue\n");
 897
 898         atomic_set(&pd->scan_queue, 0);
 899
 900         if (list_empty(&pd->cdrw.pkt_free_list)) {
 901                 VPRINTK("handle_queue: no pkt\n");
 902                 return 0;
 903         }
 904
 905         /*
 906          * Try to find a zone we are not already working on.
 907          */
 908         spin_lock(&pd->lock);
 909         first_node = pkt_rbtree_find(pd, pd->current_sector);
 910         if (!first_node) {
 911                 n = rb_first(&pd->bio_queue);
 912                 if (n)
 913                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
 914         }
 915         node = first_node;
 916         while (node) {
 917                 bio = node->bio;
 918                 zone = ZONE(bio->bi_sector, pd);
 919                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
 920                         if (p->sector == zone) {
 921                                 bio = NULL;
 922                                 goto try_next_bio;
 923                         }
 924                 }
 925                 break;
 926 try_next_bio:
 927                 node = pkt_rbtree_next(node);
 928                 if (!node) {
 929                         n = rb_first(&pd->bio_queue);
 930                         if (n)
 931                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
 932                 }
 933                 if (node == first_node)
 934                         node = NULL;
 935         }
 936         spin_unlock(&pd->lock);
 937         if (!bio) {
 938                 VPRINTK("handle_queue: no bio\n");
 939                 return 0;
 940         }
 941
 942         pkt = pkt_get_packet_data(pd, zone);
 943
 944         pd->current_sector = zone + pd->settings.size;
 945         pkt->sector = zone;
 946         BUG_ON(pkt->frames != pd->settings.size >> 2);
 947         pkt->write_size = 0;
 948
 949         /*
 950          * Scan work queue for bios in the same zone and link them
 951          * to this packet.
 952          */
 953         spin_lock(&pd->lock);
 954         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
 955         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
 956                 bio = node->bio;
 957                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
 958                         (unsigned long long)ZONE(bio->bi_sector, pd));
 959                 if (ZONE(bio->bi_sector, pd) != zone)
 960                         break;
 961                 pkt_rbtree_erase(pd, node);
 962                 spin_lock(&pkt->lock);
 963                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
 964                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
 965                 spin_unlock(&pkt->lock);
 966         }
 967         spin_unlock(&pd->lock);
 968
 969         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
 970         pkt_set_state(pkt, PACKET_WAITING_STATE);
 971         atomic_set(&pkt->run_sm, 1);
 972
 973         spin_lock(&pd->cdrw.active_list_lock);
 974         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
 975         spin_unlock(&pd->cdrw.active_list_lock);
 976
 977         return 1;
 978 }
 979
 980 /*
 981  * Assemble a bio to write one packet and queue the bio for processing
 982  * by the underlying block device.
 983  */
 984 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 985 {
 986         struct bio *bio;
 987         int f;
 988         int frames_write;
 989         struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
 990
 991         for (f = 0; f < pkt->frames; f++) {
 992                 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
 993                 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 994         }
 995
 996         /*
 997          * Fill-in bvec with data from orig_bios.
 998          */
 999         frames_write = 0;
1000         spin_lock(&pkt->lock);
1001         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1002                 int segment = bio->bi_idx;
1003                 int src_offs = 0;
1004                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1005                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1006                 BUG_ON(first_frame < 0);
1007                 BUG_ON(first_frame + num_frames > pkt->frames);
1008                 for (f = first_frame; f < first_frame + num_frames; f++) {
1009                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1010
1011                         while (src_offs >= src_bvl->bv_len) {
1012                                 src_offs -= src_bvl->bv_len;
1013                                 segment++;
1014                                 BUG_ON(segment >= bio->bi_vcnt);
1015                                 src_bvl = bio_iovec_idx(bio, segment);
1016                         }
1017
1018                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1019                                 bvec[f].bv_page = src_bvl->bv_page;
1020                                 bvec[f].bv_offset = src_bvl->bv_offset + src_offs;
1021                         } else {
1022                                 pkt_copy_bio_data(bio, segment, src_offs,
1023                                                   bvec[f].bv_page, bvec[f].bv_offset);
1024                         }
1025                         src_offs += CD_FRAMESIZE;
1026                         frames_write++;
1027                 }
1028         }
1029         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1030         spin_unlock(&pkt->lock);
1031
1032         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1033                 frames_write, (unsigned long long)pkt->sector);
1034         BUG_ON(frames_write != pkt->write_size);
1035
1036         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1037                 pkt_make_local_copy(pkt, bvec);
1038                 pkt->cache_valid = 1;
1039         } else {
1040                 pkt->cache_valid = 0;
1041         }
1042
1043         /* Start the write request */
1044         bio_init(pkt->w_bio);
1045         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1046         pkt->w_bio->bi_sector = pkt->sector;
1047         pkt->w_bio->bi_bdev = pd->bdev;
1048         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1049         pkt->w_bio->bi_private = pkt;
1050         for (f = 0; f < pkt->frames; f++)
1051                 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1052                         BUG();
1053         VPRINTK("pktcdvd: vcnt=%d\n", pkt->w_bio->bi_vcnt);
1054
1055         atomic_set(&pkt->io_wait, 1);
1056         pkt->w_bio->bi_rw = WRITE;
1057         pkt_queue_bio(pd, pkt->w_bio);
1058 }
1059
1060 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1061 {
1062         struct bio *bio, *next;
1063
1064         if (!uptodate)
1065                 pkt->cache_valid = 0;
1066
1067         /* Finish all bios corresponding to this packet */
1068         bio = pkt->orig_bios;
1069         while (bio) {
1070                 next = bio->bi_next;
1071                 bio->bi_next = NULL;
1072                 bio_endio(bio, bio->bi_size, uptodate ? 0 : -EIO);
1073                 bio = next;
1074         }
1075         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1076 }
1077
1078 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1079 {
1080         int uptodate;
1081
1082         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1083
1084         for (;;) {
1085                 switch (pkt->state) {
1086                 case PACKET_WAITING_STATE:
1087                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1088                                 return;
1089
1090                         pkt->sleep_time = 0;
1091                         pkt_gather_data(pd, pkt);
1092                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1093                         break;
1094
1095                 case PACKET_READ_WAIT_STATE:
1096                         if (atomic_read(&pkt->io_wait) > 0)
1097                                 return;
1098
1099                         if (atomic_read(&pkt->io_errors) > 0) {
1100                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1101                         } else {
1102                                 pkt_start_write(pd, pkt);
1103                         }
1104                         break;
1105
1106                 case PACKET_WRITE_WAIT_STATE:
1107                         if (atomic_read(&pkt->io_wait) > 0)
1108                                 return;
1109
1110                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1111                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1112                         } else {
1113                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1114                         }
1115                         break;
1116
1117                 case PACKET_RECOVERY_STATE:
1118                         if (pkt_start_recovery(pkt)) {
1119                                 pkt_start_write(pd, pkt);
1120                         } else {
1121                                 VPRINTK("No recovery possible\n");
1122                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1123                         }
1124                         break;
1125
1126                 case PACKET_FINISHED_STATE:
1127                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1128                         pkt_finish_packet(pkt, uptodate);
1129                         return;
1130
1131                 default:
1132                         BUG();
1133                         break;
1134                 }
1135         }
1136 }
1137
1138 static void pkt_handle_packets(struct pktcdvd_device *pd)
1139 {
1140         struct packet_data *pkt, *next;
1141
1142         VPRINTK("pkt_handle_packets\n");
1143
1144         /*
1145          * Run state machine for active packets
1146          */
1147         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1148                 if (atomic_read(&pkt->run_sm) > 0) {
1149                         atomic_set(&pkt->run_sm, 0);
1150                         pkt_run_state_machine(pd, pkt);
1151                 }
1152         }
1153
1154         /*
1155          * Move no longer active packets to the free list
1156          */
1157         spin_lock(&pd->cdrw.active_list_lock);
1158         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1159                 if (pkt->state == PACKET_FINISHED_STATE) {
1160                         list_del(&pkt->list);
1161                         pkt_put_packet_data(pd, pkt);
1162                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1163                         atomic_set(&pd->scan_queue, 1);
1164                 }
1165         }
1166         spin_unlock(&pd->cdrw.active_list_lock);
1167 }
1168
1169 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1170 {
1171         struct packet_data *pkt;
1172         int i;
1173
1174         for (i = 0; i < PACKET_NUM_STATES; i++)
1175                 states[i] = 0;
1176
1177         spin_lock(&pd->cdrw.active_list_lock);
1178         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1179                 states[pkt->state]++;
1180         }
1181         spin_unlock(&pd->cdrw.active_list_lock);
1182 }
1183
1184 /*
1185  * kcdrwd is woken up when writes have been queued for one of our
1186  * registered devices
1187  */
1188 static int kcdrwd(void *foobar)
1189 {
1190         struct pktcdvd_device *pd = foobar;
1191         struct packet_data *pkt;
1192         long min_sleep_time, residue;
1193
1194         set_user_nice(current, -20);
1195
1196         for (;;) {
1197                 DECLARE_WAITQUEUE(wait, current);
1198
1199                 /*
1200                  * Wait until there is something to do
1201                  */
1202                 add_wait_queue(&pd->wqueue, &wait);
1203                 for (;;) {
1204                         set_current_state(TASK_INTERRUPTIBLE);
1205
1206                         /* Check if we need to run pkt_handle_queue */
1207                         if (atomic_read(&pd->scan_queue) > 0)
1208                                 goto work_to_do;
1209
1210                         /* Check if we need to run the state machine for some packet */
1211                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1212                                 if (atomic_read(&pkt->run_sm) > 0)
1213                                         goto work_to_do;
1214                         }
1215
1216                         /* Check if we need to process the iosched queues */
1217                         if (atomic_read(&pd->iosched.attention) != 0)
1218                                 goto work_to_do;
1219
1220                         /* Otherwise, go to sleep */
1221                         if (PACKET_DEBUG > 1) {
1222                                 int states[PACKET_NUM_STATES];
1223                                 pkt_count_states(pd, states);
1224                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1225                                         states[0], states[1], states[2], states[3],
1226                                         states[4], states[5]);
1227                         }
1228
1229                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1230                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1231                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1232                                         min_sleep_time = pkt->sleep_time;
1233                         }
1234
1235                         generic_unplug_device(bdev_get_queue(pd->bdev));
1236
1237                         VPRINTK("kcdrwd: sleeping\n");
1238                         residue = schedule_timeout(min_sleep_time);
1239                         VPRINTK("kcdrwd: wake up\n");
1240
1241                         /* make swsusp happy with our thread */
1242                         try_to_freeze();
1243
1244                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1245                                 if (!pkt->sleep_time)
1246                                         continue;
1247                                 pkt->sleep_time -= min_sleep_time - residue;
1248                                 if (pkt->sleep_time <= 0) {
1249                                         pkt->sleep_time = 0;
1250                                         atomic_inc(&pkt->run_sm);
1251                                 }
1252                         }
1253
1254                         if (signal_pending(current)) {
1255                                 flush_signals(current);
1256                         }
1257                         if (kthread_should_stop())
1258                                 break;
1259                 }
1260 work_to_do:
1261                 set_current_state(TASK_RUNNING);
1262                 remove_wait_queue(&pd->wqueue, &wait);
1263
1264                 if (kthread_should_stop())
1265                         break;
1266
1267                 /*
1268                  * if pkt_handle_queue returns true, we can queue
1269                  * another request.
1270                  */
1271                 while (pkt_handle_queue(pd))
1272                         ;
1273
1274                 /*
1275                  * Handle packet state machine
1276                  */
1277                 pkt_handle_packets(pd);
1278
1279                 /*
1280                  * Handle iosched queues
1281                  */
1282                 pkt_iosched_process_queue(pd);
1283         }
1284
1285         return 0;
1286 }
1287
1288 static void pkt_print_settings(struct pktcdvd_device *pd)
1289 {
1290         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1291         printk("%u blocks, ", pd->settings.size >> 2);
1292         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1293 }
1294
1295 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1296 {
1297         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1298
1299         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1300         cgc->cmd[2] = page_code | (page_control << 6);
1301         cgc->cmd[7] = cgc->buflen >> 8;
1302         cgc->cmd[8] = cgc->buflen & 0xff;
1303         cgc->data_direction = CGC_DATA_READ;
1304         return pkt_generic_packet(pd, cgc);
1305 }
1306
1307 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1308 {
1309         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1310         memset(cgc->buffer, 0, 2);
1311         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1312         cgc->cmd[1] = 0x10;             /* PF */
1313         cgc->cmd[7] = cgc->buflen >> 8;
1314         cgc->cmd[8] = cgc->buflen & 0xff;
1315         cgc->data_direction = CGC_DATA_WRITE;
1316         return pkt_generic_packet(pd, cgc);
1317 }
1318
1319 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1320 {
1321         struct packet_command cgc;
1322         int ret;
1323
1324         /* set up command and get the disc info */
1325         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1326         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1327         cgc.cmd[8] = cgc.buflen = 2;
1328         cgc.quiet = 1;
1329
1330         if ((ret = pkt_generic_packet(pd, &cgc)))
1331                 return ret;
1332
1333         /* not all drives have the same disc_info length, so requeue
1334          * packet with the length the drive tells us it can supply
1335          */
1336         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1337                      sizeof(di->disc_information_length);
1338
1339         if (cgc.buflen > sizeof(disc_information))
1340                 cgc.buflen = sizeof(disc_information);
1341
1342         cgc.cmd[8] = cgc.buflen;
1343         return pkt_generic_packet(pd, &cgc);
1344 }
1345
1346 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1347 {
1348         struct packet_command cgc;
1349         int ret;
1350
1351         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1352         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1353         cgc.cmd[1] = type & 3;
1354         cgc.cmd[4] = (track & 0xff00) >> 8;
1355         cgc.cmd[5] = track & 0xff;
1356         cgc.cmd[8] = 8;
1357         cgc.quiet = 1;
1358
1359         if ((ret = pkt_generic_packet(pd, &cgc)))
1360                 return ret;
1361
1362         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1363                      sizeof(ti->track_information_length);
1364
1365         if (cgc.buflen > sizeof(track_information))
1366                 cgc.buflen = sizeof(track_information);
1367
1368         cgc.cmd[8] = cgc.buflen;
1369         return pkt_generic_packet(pd, &cgc);
1370 }
1371
1372 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1373 {
1374         disc_information di;
1375         track_information ti;
1376         __u32 last_track;
1377         int ret = -1;
1378
1379         if ((ret = pkt_get_disc_info(pd, &di)))
1380                 return ret;
1381
1382         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1383         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1384                 return ret;
1385
1386         /* if this track is blank, try the previous. */
1387         if (ti.blank) {
1388                 last_track--;
1389                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1390                         return ret;
1391         }
1392
1393         /* if last recorded field is valid, return it. */
1394         if (ti.lra_v) {
1395                 *last_written = be32_to_cpu(ti.last_rec_address);
1396         } else {
1397                 /* make it up instead */
1398                 *last_written = be32_to_cpu(ti.track_start) +
1399                                 be32_to_cpu(ti.track_size);
1400                 if (ti.free_blocks)
1401                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1402         }
1403         return 0;
1404 }
1405
1406 /*
1407  * write mode select package based on pd->settings
1408  */
1409 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1410 {
1411         struct packet_command cgc;
1412         struct request_sense sense;
1413         write_param_page *wp;
1414         char buffer[128];
1415         int ret, size;
1416
1417         /* doesn't apply to DVD+RW or DVD-RAM */
1418         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1419                 return 0;
1420
1421         memset(buffer, 0, sizeof(buffer));
1422         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1423         cgc.sense = &sense;
1424         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1425                 pkt_dump_sense(&cgc);
1426                 return ret;
1427         }
1428
1429         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1430         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1431         if (size > sizeof(buffer))
1432                 size = sizeof(buffer);
1433
1434         /*
1435          * now get it all
1436          */
1437         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1438         cgc.sense = &sense;
1439         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1440                 pkt_dump_sense(&cgc);
1441                 return ret;
1442         }
1443
1444         /*
1445          * write page is offset header + block descriptor length
1446          */
1447         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1448
1449         wp->fp = pd->settings.fp;
1450         wp->track_mode = pd->settings.track_mode;
1451         wp->write_type = pd->settings.write_type;
1452         wp->data_block_type = pd->settings.block_mode;
1453
1454         wp->multi_session = 0;
1455
1456 #ifdef PACKET_USE_LS
1457         wp->link_size = 7;
1458         wp->ls_v = 1;
1459 #endif
1460
1461         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1462                 wp->session_format = 0;
1463                 wp->subhdr2 = 0x20;
1464         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1465                 wp->session_format = 0x20;
1466                 wp->subhdr2 = 8;
1467 #if 0
1468                 wp->mcn[0] = 0x80;
1469                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1470 #endif
1471         } else {
1472                 /*
1473                  * paranoia
1474                  */
1475                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1476                 return 1;
1477         }
1478         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1479
1480         cgc.buflen = cgc.cmd[8] = size;
1481         if ((ret = pkt_mode_select(pd, &cgc))) {
1482                 pkt_dump_sense(&cgc);
1483                 return ret;
1484         }
1485
1486         pkt_print_settings(pd);
1487         return 0;
1488 }
1489
1490 /*
1491  * 1 -- we can write to this track, 0 -- we can't
1492  */
1493 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1494 {
1495         switch (pd->mmc3_profile) {
1496                 case 0x1a: /* DVD+RW */
1497                 case 0x12: /* DVD-RAM */
1498                         /* The track is always writable on DVD+RW/DVD-RAM */
1499                         return 1;
1500                 default:
1501                         break;
1502         }
1503
1504         if (!ti->packet || !ti->fp)
1505                 return 0;
1506
1507         /*
1508          * "good" settings as per Mt Fuji.
1509          */
1510         if (ti->rt == 0 && ti->blank == 0)
1511                 return 1;
1512
1513         if (ti->rt == 0 && ti->blank == 1)
1514                 return 1;
1515
1516         if (ti->rt == 1 && ti->blank == 0)
1517                 return 1;
1518
1519         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1520         return 0;
1521 }
1522
1523 /*
1524  * 1 -- we can write to this disc, 0 -- we can't
1525  */
1526 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1527 {
1528         switch (pd->mmc3_profile) {
1529                 case 0x0a: /* CD-RW */
1530                 case 0xffff: /* MMC3 not supported */
1531                         break;
1532                 case 0x1a: /* DVD+RW */
1533                 case 0x13: /* DVD-RW */
1534                 case 0x12: /* DVD-RAM */
1535                         return 1;
1536                 default:
1537                         VPRINTK("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1538                         return 0;
1539         }
1540
1541         /*
1542          * for disc type 0xff we should probably reserve a new track.
1543          * but i'm not sure, should we leave this to user apps? probably.
1544          */
1545         if (di->disc_type == 0xff) {
1546                 printk("pktcdvd: Unknown disc. No track?\n");
1547                 return 0;
1548         }
1549
1550         if (di->disc_type != 0x20 && di->disc_type != 0) {
1551                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1552                 return 0;
1553         }
1554
1555         if (di->erasable == 0) {
1556                 printk("pktcdvd: Disc not erasable\n");
1557                 return 0;
1558         }
1559
1560         if (di->border_status == PACKET_SESSION_RESERVED) {
1561                 printk("pktcdvd: Can't write to last track (reserved)\n");
1562                 return 0;
1563         }
1564
1565         return 1;
1566 }
1567
1568 static int pkt_probe_settings(struct pktcdvd_device *pd)
1569 {
1570         struct packet_command cgc;
1571         unsigned char buf[12];
1572         disc_information di;
1573         track_information ti;
1574         int ret, track;
1575
1576         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1577         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1578         cgc.cmd[8] = 8;
1579         ret = pkt_generic_packet(pd, &cgc);
1580         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1581
1582         memset(&di, 0, sizeof(disc_information));
1583         memset(&ti, 0, sizeof(track_information));
1584
1585         if ((ret = pkt_get_disc_info(pd, &di))) {
1586                 printk("failed get_disc\n");
1587                 return ret;
1588         }
1589
1590         if (!pkt_writable_disc(pd, &di))
1591                 return -EROFS;
1592
1593         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1594
1595         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1596         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1597                 printk("pktcdvd: failed get_track\n");
1598                 return ret;
1599         }
1600
1601         if (!pkt_writable_track(pd, &ti)) {
1602                 printk("pktcdvd: can't write to this track\n");
1603                 return -EROFS;
1604         }
1605
1606         /*
1607          * we keep packet size in 512 byte units, makes it easier to
1608          * deal with request calculations.
1609          */
1610         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1611         if (pd->settings.size == 0) {
1612                 printk("pktcdvd: detected zero packet size!\n");
1613                 return -ENXIO;
1614         }
1615         if (pd->settings.size > PACKET_MAX_SECTORS) {
1616                 printk("pktcdvd: packet size is too big\n");
1617                 return -EROFS;
1618         }
1619         pd->settings.fp = ti.fp;
1620         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1621
1622         if (ti.nwa_v) {
1623                 pd->nwa = be32_to_cpu(ti.next_writable);
1624                 set_bit(PACKET_NWA_VALID, &pd->flags);
1625         }
1626
1627         /*
1628          * in theory we could use lra on -RW media as well and just zero
1629          * blocks that haven't been written yet, but in practice that
1630          * is just a no-go. we'll use that for -R, naturally.
1631          */
1632         if (ti.lra_v) {
1633                 pd->lra = be32_to_cpu(ti.last_rec_address);
1634                 set_bit(PACKET_LRA_VALID, &pd->flags);
1635         } else {
1636                 pd->lra = 0xffffffff;
1637                 set_bit(PACKET_LRA_VALID, &pd->flags);
1638         }
1639
1640         /*
1641          * fine for now
1642          */
1643         pd->settings.link_loss = 7;
1644         pd->settings.write_type = 0;    /* packet */
1645         pd->settings.track_mode = ti.track_mode;
1646
1647         /*
1648          * mode1 or mode2 disc
1649          */
1650         switch (ti.data_mode) {
1651                 case PACKET_MODE1:
1652                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1653                         break;
1654                 case PACKET_MODE2:
1655                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1656                         break;
1657                 default:
1658                         printk("pktcdvd: unknown data mode\n");
1659                         return -EROFS;
1660         }
1661         return 0;
1662 }
1663
1664 /*
1665  * enable/disable write caching on drive
1666  */
1667 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1668 {
1669         struct packet_command cgc;
1670         struct request_sense sense;
1671         unsigned char buf[64];
1672         int ret;
1673
1674         memset(buf, 0, sizeof(buf));
1675         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1676         cgc.sense = &sense;
1677         cgc.buflen = pd->mode_offset + 12;
1678
1679         /*
1680          * caching mode page might not be there, so quiet this command
1681          */
1682         cgc.quiet = 1;
1683
1684         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1685                 return ret;
1686
1687         buf[pd->mode_offset + 10] |= (!!set << 2);
1688
1689         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1690         ret = pkt_mode_select(pd, &cgc);
1691         if (ret) {
1692                 printk("pktcdvd: write caching control failed\n");
1693                 pkt_dump_sense(&cgc);
1694         } else if (!ret && set)
1695                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1696         return ret;
1697 }
1698
1699 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1700 {
1701         struct packet_command cgc;
1702
1703         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1704         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1705         cgc.cmd[4] = lockflag ? 1 : 0;
1706         return pkt_generic_packet(pd, &cgc);
1707 }
1708
1709 /*
1710  * Returns drive maximum write speed
1711  */
1712 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1713 {
1714         struct packet_command cgc;
1715         struct request_sense sense;
1716         unsigned char buf[256+18];
1717         unsigned char *cap_buf;
1718         int ret, offset;
1719
1720         memset(buf, 0, sizeof(buf));
1721         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1722         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1723         cgc.sense = &sense;
1724
1725         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1726         if (ret) {
1727                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1728                              sizeof(struct mode_page_header);
1729                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1730                 if (ret) {
1731                         pkt_dump_sense(&cgc);
1732                         return ret;
1733                 }
1734         }
1735
1736         offset = 20;                        /* Obsoleted field, used by older drives */
1737         if (cap_buf[1] >= 28)
1738                 offset = 28;                /* Current write speed selected */
1739         if (cap_buf[1] >= 30) {
1740                 /* If the drive reports at least one "Logical Unit Write
1741                  * Speed Performance Descriptor Block", use the information
1742                  * in the first block. (contains the highest speed)
1743                  */
1744                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1745                 if (num_spdb > 0)
1746                         offset = 34;
1747         }
1748
1749         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1750         return 0;
1751 }
1752
1753 /* These tables from cdrecord - I don't have orange book */
1754 /* standard speed CD-RW (1-4x) */
1755 static char clv_to_speed[16] = {
1756         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1757            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1758 };
1759 /* high speed CD-RW (-10x) */
1760 static char hs_clv_to_speed[16] = {
1761         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1762            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1763 };
1764 /* ultra high speed CD-RW */
1765 static char us_clv_to_speed[16] = {
1766         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1767            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1768 };
1769
1770 /*
1771  * reads the maximum media speed from ATIP
1772  */
1773 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1774 {
1775         struct packet_command cgc;
1776         struct request_sense sense;
1777         unsigned char buf[64];
1778         unsigned int size, st, sp;
1779         int ret;
1780
1781         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1782         cgc.sense = &sense;
1783         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1784         cgc.cmd[1] = 2;
1785         cgc.cmd[2] = 4; /* READ ATIP */
1786         cgc.cmd[8] = 2;
1787         ret = pkt_generic_packet(pd, &cgc);
1788         if (ret) {
1789                 pkt_dump_sense(&cgc);
1790                 return ret;
1791         }
1792         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1793         if (size > sizeof(buf))
1794                 size = sizeof(buf);
1795
1796         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1797         cgc.sense = &sense;
1798         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1799         cgc.cmd[1] = 2;
1800         cgc.cmd[2] = 4;
1801         cgc.cmd[8] = size;
1802         ret = pkt_generic_packet(pd, &cgc);
1803         if (ret) {
1804                 pkt_dump_sense(&cgc);
1805                 return ret;
1806         }
1807
1808         if (!buf[6] & 0x40) {
1809                 printk("pktcdvd: Disc type is not CD-RW\n");
1810                 return 1;
1811         }
1812         if (!buf[6] & 0x4) {
1813                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1814                 return 1;
1815         }
1816
1817         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1818
1819         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1820
1821         /* Info from cdrecord */
1822         switch (st) {
1823                 case 0: /* standard speed */
1824                         *speed = clv_to_speed[sp];
1825                         break;
1826                 case 1: /* high speed */
1827                         *speed = hs_clv_to_speed[sp];
1828                         break;
1829                 case 2: /* ultra high speed */
1830                         *speed = us_clv_to_speed[sp];
1831                         break;
1832                 default:
1833                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1834                         return 1;
1835         }
1836         if (*speed) {
1837                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1838                 return 0;
1839         } else {
1840                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1841                 return 1;
1842         }
1843 }
1844
1845 static int pkt_perform_opc(struct pktcdvd_device *pd)
1846 {
1847         struct packet_command cgc;
1848         struct request_sense sense;
1849         int ret;
1850
1851         VPRINTK("pktcdvd: Performing OPC\n");
1852
1853         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1854         cgc.sense = &sense;
1855         cgc.timeout = 60*HZ;
1856         cgc.cmd[0] = GPCMD_SEND_OPC;
1857         cgc.cmd[1] = 1;
1858         if ((ret = pkt_generic_packet(pd, &cgc)))
1859                 pkt_dump_sense(&cgc);
1860         return ret;
1861 }
1862
1863 static int pkt_open_write(struct pktcdvd_device *pd)
1864 {
1865         int ret;
1866         unsigned int write_speed, media_write_speed, read_speed;
1867
1868         if ((ret = pkt_probe_settings(pd))) {
1869                 VPRINTK("pktcdvd: %s failed probe\n", pd->name);
1870                 return ret;
1871         }
1872
1873         if ((ret = pkt_set_write_settings(pd))) {
1874                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1875                 return -EIO;
1876         }
1877
1878         pkt_write_caching(pd, USE_WCACHING);
1879
1880         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1881                 write_speed = 16 * 177;
1882         switch (pd->mmc3_profile) {
1883                 case 0x13: /* DVD-RW */
1884                 case 0x1a: /* DVD+RW */
1885                 case 0x12: /* DVD-RAM */
1886                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1887                         break;
1888                 default:
1889                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1890                                 media_write_speed = 16;
1891                         write_speed = min(write_speed, media_write_speed * 177);
1892                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1893                         break;
1894         }
1895         read_speed = write_speed;
1896
1897         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1898                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1899                 return -EIO;
1900         }
1901         pd->write_speed = write_speed;
1902         pd->read_speed = read_speed;
1903
1904         if ((ret = pkt_perform_opc(pd))) {
1905                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1906         }
1907
1908         return 0;
1909 }
1910
1911 /*
1912  * called at open time.
1913  */
1914 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1915 {
1916         int ret;
1917         long lba;
1918         request_queue_t *q;
1919
1920         /*
1921          * We need to re-open the cdrom device without O_NONBLOCK to be able
1922          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1923          * so bdget() can't fail.
1924          */
1925         bdget(pd->bdev->bd_dev);
1926         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1927                 goto out;
1928
1929         if ((ret = bd_claim(pd->bdev, pd)))
1930                 goto out_putdev;
1931
1932         if ((ret = pkt_get_last_written(pd, &lba))) {
1933                 printk("pktcdvd: pkt_get_last_written failed\n");
1934                 goto out_unclaim;
1935         }
1936
1937         set_capacity(pd->disk, lba << 2);
1938         set_capacity(pd->bdev->bd_disk, lba << 2);
1939         bd_set_size(pd->bdev, (loff_t)lba << 11);
1940
1941         q = bdev_get_queue(pd->bdev);
1942         if (write) {
1943                 if ((ret = pkt_open_write(pd)))
1944                         goto out_unclaim;
1945                 /*
1946                  * Some CDRW drives can not handle writes larger than one packet,
1947                  * even if the size is a multiple of the packet size.
1948                  */
1949                 spin_lock_irq(q->queue_lock);
1950                 blk_queue_max_sectors(q, pd->settings.size);
1951                 spin_unlock_irq(q->queue_lock);
1952                 set_bit(PACKET_WRITABLE, &pd->flags);
1953         } else {
1954                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1955                 clear_bit(PACKET_WRITABLE, &pd->flags);
1956         }
1957
1958         if ((ret = pkt_set_segment_merging(pd, q)))
1959                 goto out_unclaim;
1960
1961         if (write) {
1962                 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
1963                         printk("pktcdvd: not enough memory for buffers\n");
1964                         ret = -ENOMEM;
1965                         goto out_unclaim;
1966                 }
1967                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1968         }
1969
1970         return 0;
1971
1972 out_unclaim:
1973         bd_release(pd->bdev);
1974 out_putdev:
1975         blkdev_put(pd->bdev);
1976 out:
1977         return ret;
1978 }
1979
1980 /*
1981  * called when the device is closed. makes sure that the device flushes
1982  * the internal cache before we close.
1983  */
1984 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
1985 {
1986         if (flush && pkt_flush_cache(pd))
1987                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
1988
1989         pkt_lock_door(pd, 0);
1990
1991         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1992         bd_release(pd->bdev);
1993         blkdev_put(pd->bdev);
1994
1995         pkt_shrink_pktlist(pd);
1996 }
1997
1998 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
1999 {
2000         if (dev_minor >= MAX_WRITERS)
2001                 return NULL;
2002         return pkt_devs[dev_minor];
2003 }
2004
2005 static int pkt_open(struct inode *inode, struct file *file)
2006 {
2007         struct pktcdvd_device *pd = NULL;
2008         int ret;
2009
2010         VPRINTK("pktcdvd: entering open\n");
2011
2012         mutex_lock(&ctl_mutex);
2013         pd = pkt_find_dev_from_minor(iminor(inode));
2014         if (!pd) {
2015                 ret = -ENODEV;
2016                 goto out;
2017         }
2018         BUG_ON(pd->refcnt < 0);
2019
2020         pd->refcnt++;
2021         if (pd->refcnt > 1) {
2022                 if ((file->f_mode & FMODE_WRITE) &&
2023                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2024                         ret = -EBUSY;
2025                         goto out_dec;
2026                 }
2027         } else {
2028                 ret = pkt_open_dev(pd, file->f_mode & FMODE_WRITE);
2029                 if (ret)
2030                         goto out_dec;
2031                 /*
2032                  * needed here as well, since ext2 (among others) may change
2033                  * the blocksize at mount time
2034                  */
2035                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2036         }
2037
2038         mutex_unlock(&ctl_mutex);
2039         return 0;
2040
2041 out_dec:
2042         pd->refcnt--;
2043 out:
2044         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2045         mutex_unlock(&ctl_mutex);
2046         return ret;
2047 }
2048
2049 static int pkt_close(struct inode *inode, struct file *file)
2050 {
2051         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2052         int ret = 0;
2053
2054         mutex_lock(&ctl_mutex);
2055         pd->refcnt--;
2056         BUG_ON(pd->refcnt < 0);
2057         if (pd->refcnt == 0) {
2058                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2059                 pkt_release_dev(pd, flush);
2060         }
2061         mutex_unlock(&ctl_mutex);
2062         return ret;
2063 }
2064
2065
2066 static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int err)
2067 {
2068         struct packet_stacked_data *psd = bio->bi_private;
2069         struct pktcdvd_device *pd = psd->pd;
2070
2071         if (bio->bi_size)
2072                 return 1;
2073
2074         bio_put(bio);
2075         bio_endio(psd->bio, psd->bio->bi_size, err);
2076         mempool_free(psd, psd_pool);
2077         pkt_bio_finished(pd);
2078         return 0;
2079 }
2080
2081 static int pkt_make_request(request_queue_t *q, struct bio *bio)
2082 {
2083         struct pktcdvd_device *pd;
2084         char b[BDEVNAME_SIZE];
2085         sector_t zone;
2086         struct packet_data *pkt;
2087         int was_empty, blocked_bio;
2088         struct pkt_rb_node *node;
2089
2090         pd = q->queuedata;
2091         if (!pd) {
2092                 printk("pktcdvd: %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2093                 goto end_io;
2094         }
2095
2096         /*
2097          * Clone READ bios so we can have our own bi_end_io callback.
2098          */
2099         if (bio_data_dir(bio) == READ) {
2100                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2101                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2102
2103                 psd->pd = pd;
2104                 psd->bio = bio;
2105                 cloned_bio->bi_bdev = pd->bdev;
2106                 cloned_bio->bi_private = psd;
2107                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2108                 pd->stats.secs_r += bio->bi_size >> 9;
2109                 pkt_queue_bio(pd, cloned_bio);
2110                 return 0;
2111         }
2112
2113         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2114                 printk("pktcdvd: WRITE for ro device %s (%llu)\n",
2115                         pd->name, (unsigned long long)bio->bi_sector);
2116                 goto end_io;
2117         }
2118
2119         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2120                 printk("pktcdvd: wrong bio size\n");
2121                 goto end_io;
2122         }
2123
2124         blk_queue_bounce(q, &bio);
2125
2126         zone = ZONE(bio->bi_sector, pd);
2127         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2128                 (unsigned long long)bio->bi_sector,
2129                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2130
2131         /* Check if we have to split the bio */
2132         {
2133                 struct bio_pair *bp;
2134                 sector_t last_zone;
2135                 int first_sectors;
2136
2137                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2138                 if (last_zone != zone) {
2139                         BUG_ON(last_zone != zone + pd->settings.size);
2140                         first_sectors = last_zone - bio->bi_sector;
2141                         bp = bio_split(bio, bio_split_pool, first_sectors);
2142                         BUG_ON(!bp);
2143                         pkt_make_request(q, &bp->bio1);
2144                         pkt_make_request(q, &bp->bio2);
2145                         bio_pair_release(bp);
2146                         return 0;
2147                 }
2148         }
2149
2150         /*
2151          * If we find a matching packet in state WAITING or READ_WAIT, we can
2152          * just append this bio to that packet.
2153          */
2154         spin_lock(&pd->cdrw.active_list_lock);
2155         blocked_bio = 0;
2156         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2157                 if (pkt->sector == zone) {
2158                         spin_lock(&pkt->lock);
2159                         if ((pkt->state == PACKET_WAITING_STATE) ||
2160                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2161                                 pkt_add_list_last(bio, &pkt->orig_bios,
2162                                                   &pkt->orig_bios_tail);
2163                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2164                                 if ((pkt->write_size >= pkt->frames) &&
2165                                     (pkt->state == PACKET_WAITING_STATE)) {
2166                                         atomic_inc(&pkt->run_sm);
2167                                         wake_up(&pd->wqueue);
2168                                 }
2169                                 spin_unlock(&pkt->lock);
2170                                 spin_unlock(&pd->cdrw.active_list_lock);
2171                                 return 0;
2172                         } else {
2173                                 blocked_bio = 1;
2174                         }
2175                         spin_unlock(&pkt->lock);
2176                 }
2177         }
2178         spin_unlock(&pd->cdrw.active_list_lock);
2179
2180         /*
2181          * No matching packet found. Store the bio in the work queue.
2182          */
2183         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2184         node->bio = bio;
2185         spin_lock(&pd->lock);
2186         BUG_ON(pd->bio_queue_size < 0);
2187         was_empty = (pd->bio_queue_size == 0);
2188         pkt_rbtree_insert(pd, node);
2189         spin_unlock(&pd->lock);
2190
2191         /*
2192          * Wake up the worker thread.
2193          */
2194         atomic_set(&pd->scan_queue, 1);
2195         if (was_empty) {
2196                 /* This wake_up is required for correct operation */
2197                 wake_up(&pd->wqueue);
2198         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2199                 /*
2200                  * This wake up is not required for correct operation,
2201                  * but improves performance in some cases.
2202                  */
2203                 wake_up(&pd->wqueue);
2204         }
2205         return 0;
2206 end_io:
2207         bio_io_error(bio, bio->bi_size);
2208         return 0;
2209 }
2210
2211
2212
2213 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2214 {
2215         struct pktcdvd_device *pd = q->queuedata;
2216         sector_t zone = ZONE(bio->bi_sector, pd);
2217         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2218         int remaining = (pd->settings.size << 9) - used;
2219         int remaining2;
2220
2221         /*
2222          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2223          * boundary, pkt_make_request() will split the bio.
2224          */
2225         remaining2 = PAGE_SIZE - bio->bi_size;
2226         remaining = max(remaining, remaining2);
2227
2228         BUG_ON(remaining < 0);
2229         return remaining;
2230 }
2231
2232 static void pkt_init_queue(struct pktcdvd_device *pd)
2233 {
2234         request_queue_t *q = pd->disk->queue;
2235
2236         blk_queue_make_request(q, pkt_make_request);
2237         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2238         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2239         blk_queue_merge_bvec(q, pkt_merge_bvec);
2240         q->queuedata = pd;
2241 }
2242
2243 static int pkt_seq_show(struct seq_file *m, void *p)
2244 {
2245         struct pktcdvd_device *pd = m->private;
2246         char *msg;
2247         char bdev_buf[BDEVNAME_SIZE];
2248         int states[PACKET_NUM_STATES];
2249
2250         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2251                    bdevname(pd->bdev, bdev_buf));
2252
2253         seq_printf(m, "\nSettings:\n");
2254         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2255
2256         if (pd->settings.write_type == 0)
2257                 msg = "Packet";
2258         else
2259                 msg = "Unknown";
2260         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2261
2262         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2263         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2264
2265         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2266
2267         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2268                 msg = "Mode 1";
2269         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2270                 msg = "Mode 2";
2271         else
2272                 msg = "Unknown";
2273         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2274
2275         seq_printf(m, "\nStatistics:\n");
2276         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2277         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2278         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2279         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2280         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2281
2282         seq_printf(m, "\nMisc:\n");
2283         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2284         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2285         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2286         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2287         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2288         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2289
2290         seq_printf(m, "\nQueue state:\n");
2291         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2292         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2293         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2294
2295         pkt_count_states(pd, states);
2296         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2297                    states[0], states[1], states[2], states[3], states[4], states[5]);
2298
2299         return 0;
2300 }
2301
2302 static int pkt_seq_open(struct inode *inode, struct file *file)
2303 {
2304         return single_open(file, pkt_seq_show, PDE(inode)->data);
2305 }
2306
2307 static struct file_operations pkt_proc_fops = {
2308         .open   = pkt_seq_open,
2309         .read   = seq_read,
2310         .llseek = seq_lseek,
2311         .release = single_release
2312 };
2313
2314 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2315 {
2316         int i;
2317         int ret = 0;
2318         char b[BDEVNAME_SIZE];
2319         struct proc_dir_entry *proc;
2320         struct block_device *bdev;
2321
2322         if (pd->pkt_dev == dev) {
2323                 printk("pktcdvd: Recursive setup not allowed\n");
2324                 return -EBUSY;
2325         }
2326         for (i = 0; i < MAX_WRITERS; i++) {
2327                 struct pktcdvd_device *pd2 = pkt_devs[i];
2328                 if (!pd2)
2329                         continue;
2330                 if (pd2->bdev->bd_dev == dev) {
2331                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2332                         return -EBUSY;
2333                 }
2334                 if (pd2->pkt_dev == dev) {
2335                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2336                         return -EBUSY;
2337                 }
2338         }
2339
2340         bdev = bdget(dev);
2341         if (!bdev)
2342                 return -ENOMEM;
2343         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2344         if (ret)
2345                 return ret;
2346
2347         /* This is safe, since we have a reference from open(). */
2348         __module_get(THIS_MODULE);
2349
2350         pd->bdev = bdev;
2351         set_blocksize(bdev, CD_FRAMESIZE);
2352
2353         pkt_init_queue(pd);
2354
2355         atomic_set(&pd->cdrw.pending_bios, 0);
2356         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2357         if (IS_ERR(pd->cdrw.thread)) {
2358                 printk("pktcdvd: can't start kernel thread\n");
2359                 ret = -ENOMEM;
2360                 goto out_mem;
2361         }
2362
2363         proc = create_proc_entry(pd->name, 0, pkt_proc);
2364         if (proc) {
2365                 proc->data = pd;
2366                 proc->proc_fops = &pkt_proc_fops;
2367         }
2368         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2369         return 0;
2370
2371 out_mem:
2372         blkdev_put(bdev);
2373         /* This is safe: open() is still holding a reference. */
2374         module_put(THIS_MODULE);
2375         return ret;
2376 }
2377
2378 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2379 {
2380         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2381
2382         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2383
2384         switch (cmd) {
2385         /*
2386          * forward selected CDROM ioctls to CD-ROM, for UDF
2387          */
2388         case CDROMMULTISESSION:
2389         case CDROMREADTOCENTRY:
2390         case CDROM_LAST_WRITTEN:
2391         case CDROM_SEND_PACKET:
2392         case SCSI_IOCTL_SEND_COMMAND:
2393                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2394
2395         case CDROMEJECT:
2396                 /*
2397                  * The door gets locked when the device is opened, so we
2398                  * have to unlock it or else the eject command fails.
2399                  */
2400                 if (pd->refcnt == 1)
2401                         pkt_lock_door(pd, 0);
2402                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2403
2404         default:
2405                 VPRINTK("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2406                 return -ENOTTY;
2407         }
2408
2409         return 0;
2410 }
2411
2412 static int pkt_media_changed(struct gendisk *disk)
2413 {
2414         struct pktcdvd_device *pd = disk->private_data;
2415         struct gendisk *attached_disk;
2416
2417         if (!pd)
2418                 return 0;
2419         if (!pd->bdev)
2420                 return 0;
2421         attached_disk = pd->bdev->bd_disk;
2422         if (!attached_disk)
2423                 return 0;
2424         return attached_disk->fops->media_changed(attached_disk);
2425 }
2426
2427 static struct block_device_operations pktcdvd_ops = {
2428         .owner =                THIS_MODULE,
2429         .open =                 pkt_open,
2430         .release =              pkt_close,
2431         .ioctl =                pkt_ioctl,
2432         .media_changed =        pkt_media_changed,
2433 };
2434
2435 /*
2436  * Set up mapping from pktcdvd device to CD-ROM device.
2437  */
2438 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2439 {
2440         int idx;
2441         int ret = -ENOMEM;
2442         struct pktcdvd_device *pd;
2443         struct gendisk *disk;
2444         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2445
2446         for (idx = 0; idx < MAX_WRITERS; idx++)
2447                 if (!pkt_devs[idx])
2448                         break;
2449         if (idx == MAX_WRITERS) {
2450                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2451                 return -EBUSY;
2452         }
2453
2454         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2455         if (!pd)
2456                 return ret;
2457
2458         pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2459                                                   sizeof(struct pkt_rb_node));
2460         if (!pd->rb_pool)
2461                 goto out_mem;
2462
2463         disk = alloc_disk(1);
2464         if (!disk)
2465                 goto out_mem;
2466         pd->disk = disk;
2467
2468         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2469         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2470         spin_lock_init(&pd->cdrw.active_list_lock);
2471
2472         spin_lock_init(&pd->lock);
2473         spin_lock_init(&pd->iosched.lock);
2474         sprintf(pd->name, "pktcdvd%d", idx);
2475         init_waitqueue_head(&pd->wqueue);
2476         pd->bio_queue = RB_ROOT;
2477
2478         disk->major = pkt_major;
2479         disk->first_minor = idx;
2480         disk->fops = &pktcdvd_ops;
2481         disk->flags = GENHD_FL_REMOVABLE;
2482         sprintf(disk->disk_name, "pktcdvd%d", idx);
2483         disk->private_data = pd;
2484         disk->queue = blk_alloc_queue(GFP_KERNEL);
2485         if (!disk->queue)
2486                 goto out_mem2;
2487
2488         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2489         ret = pkt_new_dev(pd, dev);
2490         if (ret)
2491                 goto out_new_dev;
2492
2493         add_disk(disk);
2494         pkt_devs[idx] = pd;
2495         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2496         return 0;
2497
2498 out_new_dev:
2499         blk_cleanup_queue(disk->queue);
2500 out_mem2:
2501         put_disk(disk);
2502 out_mem:
2503         if (pd->rb_pool)
2504                 mempool_destroy(pd->rb_pool);
2505         kfree(pd);
2506         return ret;
2507 }
2508
2509 /*
2510  * Tear down mapping from pktcdvd device to CD-ROM device.
2511  */
2512 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2513 {
2514         struct pktcdvd_device *pd;
2515         int idx;
2516         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2517
2518         for (idx = 0; idx < MAX_WRITERS; idx++) {
2519                 pd = pkt_devs[idx];
2520                 if (pd && (pd->pkt_dev == pkt_dev))
2521                         break;
2522         }
2523         if (idx == MAX_WRITERS) {
2524                 DPRINTK("pktcdvd: dev not setup\n");
2525                 return -ENXIO;
2526         }
2527
2528         if (pd->refcnt > 0)
2529                 return -EBUSY;
2530
2531         if (!IS_ERR(pd->cdrw.thread))
2532                 kthread_stop(pd->cdrw.thread);
2533
2534         blkdev_put(pd->bdev);
2535
2536         remove_proc_entry(pd->name, pkt_proc);
2537         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2538
2539         del_gendisk(pd->disk);
2540         blk_cleanup_queue(pd->disk->queue);
2541         put_disk(pd->disk);
2542
2543         pkt_devs[idx] = NULL;
2544         mempool_destroy(pd->rb_pool);
2545         kfree(pd);
2546
2547         /* This is safe: open() is still holding a reference. */
2548         module_put(THIS_MODULE);
2549         return 0;
2550 }
2551
2552 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2553 {
2554         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2555         if (pd) {
2556                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2557                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2558         } else {
2559                 ctrl_cmd->dev = 0;
2560                 ctrl_cmd->pkt_dev = 0;
2561         }
2562         ctrl_cmd->num_devices = MAX_WRITERS;
2563 }
2564
2565 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2566 {
2567         void __user *argp = (void __user *)arg;
2568         struct pkt_ctrl_command ctrl_cmd;
2569         int ret = 0;
2570
2571         if (cmd != PACKET_CTRL_CMD)
2572                 return -ENOTTY;
2573
2574         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2575                 return -EFAULT;
2576
2577         switch (ctrl_cmd.command) {
2578         case PKT_CTRL_CMD_SETUP:
2579                 if (!capable(CAP_SYS_ADMIN))
2580                         return -EPERM;
2581                 mutex_lock(&ctl_mutex);
2582                 ret = pkt_setup_dev(&ctrl_cmd);
2583                 mutex_unlock(&ctl_mutex);
2584                 break;
2585         case PKT_CTRL_CMD_TEARDOWN:
2586                 if (!capable(CAP_SYS_ADMIN))
2587                         return -EPERM;
2588                 mutex_lock(&ctl_mutex);
2589                 ret = pkt_remove_dev(&ctrl_cmd);
2590                 mutex_unlock(&ctl_mutex);
2591                 break;
2592         case PKT_CTRL_CMD_STATUS:
2593                 mutex_lock(&ctl_mutex);
2594                 pkt_get_status(&ctrl_cmd);
2595                 mutex_unlock(&ctl_mutex);
2596                 break;
2597         default:
2598                 return -ENOTTY;
2599         }
2600
2601         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2602                 return -EFAULT;
2603         return ret;
2604 }
2605
2606
2607 static struct file_operations pkt_ctl_fops = {
2608         .ioctl   = pkt_ctl_ioctl,
2609         .owner   = THIS_MODULE,
2610 };
2611
2612 static struct miscdevice pkt_misc = {
2613         .minor          = MISC_DYNAMIC_MINOR,
2614         .name           = "pktcdvd",
2615         .devfs_name     = "pktcdvd/control",
2616         .fops           = &pkt_ctl_fops
2617 };
2618
2619 static int __init pkt_init(void)
2620 {
2621         int ret;
2622
2623         psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
2624                                         sizeof(struct packet_stacked_data));
2625         if (!psd_pool)
2626                 return -ENOMEM;
2627
2628         ret = register_blkdev(pkt_major, "pktcdvd");
2629         if (ret < 0) {
2630                 printk("pktcdvd: Unable to register block device\n");
2631                 goto out2;
2632         }
2633         if (!pkt_major)
2634                 pkt_major = ret;
2635
2636         ret = misc_register(&pkt_misc);
2637         if (ret) {
2638                 printk("pktcdvd: Unable to register misc device\n");
2639                 goto out;
2640         }
2641
2642         mutex_init(&ctl_mutex);
2643
2644         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2645
2646         return 0;
2647
2648 out:
2649         unregister_blkdev(pkt_major, "pktcdvd");
2650 out2:
2651         mempool_destroy(psd_pool);
2652         return ret;
2653 }
2654
2655 static void __exit pkt_exit(void)
2656 {
2657         remove_proc_entry("pktcdvd", proc_root_driver);
2658         misc_deregister(&pkt_misc);
2659         unregister_blkdev(pkt_major, "pktcdvd");
2660         mempool_destroy(psd_pool);
2661 }
2662
2663 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2664 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2665 MODULE_LICENSE("GPL");
2666
2667 module_init(pkt_init);
2668 module_exit(pkt_exit);