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-R, CD-RW, DVD-R, and
   9  * DVD-RW devices (aka an exercise in block layer masturbation)
  10  *
  11  *
  12  * TODO: (circa order of when I will fix it)
  13  * - Only able to write on CD-RW media right now.
  14  * - check host application code on media and set it in write page
  15  * - interface for UDF <-> packet to negotiate a new location when a write
  16  *   fails.
  17  * - handle OPC, especially for -RW media
  18  *
  19  * Theory of operation:
  20  *
  21  * We use a custom make_request_fn function that forwards reads directly to
  22  * the underlying CD device. Write requests are either attached directly to
  23  * a live packet_data object, or simply stored sequentially in a list for
  24  * later processing by the kcdrwd kernel thread. This driver doesn't use
  25  * any elevator functionally as defined by the elevator_s struct, but the
  26  * underlying CD device uses a standard elevator.
  27  *
  28  * This strategy makes it possible to do very late merging of IO requests.
  29  * A new bio sent to pkt_make_request can be merged with a live packet_data
  30  * object even if the object is in the data gathering state.
  31  *
  32  *************************************************************************/
  33
  34 #define VERSION_CODE    "v0.2.0a 2004-07-14 Jens Axboe (axboe@suse.de) and petero2@telia.com"
  35
  36 #include <linux/pktcdvd.h>
  37 #include <linux/config.h>
  38 #include <linux/module.h>
  39 #include <linux/types.h>
  40 #include <linux/kernel.h>
  41 #include <linux/kthread.h>
  42 #include <linux/errno.h>
  43 #include <linux/spinlock.h>
  44 #include <linux/file.h>
  45 #include <linux/proc_fs.h>
  46 #include <linux/seq_file.h>
  47 #include <linux/miscdevice.h>
  48 #include <linux/suspend.h>
  49 #include <scsi/scsi_cmnd.h>
  50 #include <scsi/scsi_ioctl.h>
  51
  52 #include <asm/uaccess.h>
  53
  54 #if PACKET_DEBUG
  55 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  56 #else
  57 #define DPRINTK(fmt, args...)
  58 #endif
  59
  60 #if PACKET_DEBUG > 1
  61 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  62 #else
  63 #define VPRINTK(fmt, args...)
  64 #endif
  65
  66 #define MAX_SPEED 0xffff
  67
  68 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  69
  70 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  71 static struct proc_dir_entry *pkt_proc;
  72 static int pkt_major;
  73 static struct semaphore ctl_mutex;      /* Serialize open/close/setup/teardown */
  74 static mempool_t *psd_pool;
  75
  76
  77 static void pkt_bio_finished(struct pktcdvd_device *pd)
  78 {
  79         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
  80         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
  81                 VPRINTK("pktcdvd: queue empty\n");
  82                 atomic_set(&pd->iosched.attention, 1);
  83                 wake_up(&pd->wqueue);
  84         }
  85 }
  86
  87 static void pkt_bio_destructor(struct bio *bio)
  88 {
  89         kfree(bio->bi_io_vec);
  90         kfree(bio);
  91 }
  92
  93 static struct bio *pkt_bio_alloc(int nr_iovecs)
  94 {
  95         struct bio_vec *bvl = NULL;
  96         struct bio *bio;
  97
  98         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
  99         if (!bio)
 100                 goto no_bio;
 101         bio_init(bio);
 102
 103         bvl = kmalloc(nr_iovecs * sizeof(struct bio_vec), GFP_KERNEL);
 104         if (!bvl)
 105                 goto no_bvl;
 106         memset(bvl, 0, nr_iovecs * sizeof(struct bio_vec));
 107
 108         bio->bi_max_vecs = nr_iovecs;
 109         bio->bi_io_vec = bvl;
 110         bio->bi_destructor = pkt_bio_destructor;
 111
 112         return bio;
 113
 114  no_bvl:
 115         kfree(bio);
 116  no_bio:
 117         return NULL;
 118 }
 119
 120 /*
 121  * Allocate a packet_data struct
 122  */
 123 static struct packet_data *pkt_alloc_packet_data(void)
 124 {
 125         int i;
 126         struct packet_data *pkt;
 127
 128         pkt = kmalloc(sizeof(struct packet_data), GFP_KERNEL);
 129         if (!pkt)
 130                 goto no_pkt;
 131         memset(pkt, 0, sizeof(struct packet_data));
 132
 133         pkt->w_bio = pkt_bio_alloc(PACKET_MAX_SIZE);
 134         if (!pkt->w_bio)
 135                 goto no_bio;
 136
 137         for (i = 0; i < PAGES_PER_PACKET; i++) {
 138                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 139                 if (!pkt->pages[i])
 140                         goto no_page;
 141         }
 142
 143         spin_lock_init(&pkt->lock);
 144
 145         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 146                 struct bio *bio = pkt_bio_alloc(1);
 147                 if (!bio)
 148                         goto no_rd_bio;
 149                 pkt->r_bios[i] = bio;
 150         }
 151
 152         return pkt;
 153
 154 no_rd_bio:
 155         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 156                 struct bio *bio = pkt->r_bios[i];
 157                 if (bio)
 158                         bio_put(bio);
 159         }
 160
 161 no_page:
 162         for (i = 0; i < PAGES_PER_PACKET; i++)
 163                 if (pkt->pages[i])
 164                         __free_page(pkt->pages[i]);
 165         bio_put(pkt->w_bio);
 166 no_bio:
 167         kfree(pkt);
 168 no_pkt:
 169         return NULL;
 170 }
 171
 172 /*
 173  * Free a packet_data struct
 174  */
 175 static void pkt_free_packet_data(struct packet_data *pkt)
 176 {
 177         int i;
 178
 179         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 180                 struct bio *bio = pkt->r_bios[i];
 181                 if (bio)
 182                         bio_put(bio);
 183         }
 184         for (i = 0; i < PAGES_PER_PACKET; i++)
 185                 __free_page(pkt->pages[i]);
 186         bio_put(pkt->w_bio);
 187         kfree(pkt);
 188 }
 189
 190 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 191 {
 192         struct packet_data *pkt, *next;
 193
 194         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 195
 196         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 197                 pkt_free_packet_data(pkt);
 198         }
 199 }
 200
 201 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 202 {
 203         struct packet_data *pkt;
 204
 205         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 206         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
 207         spin_lock_init(&pd->cdrw.active_list_lock);
 208         while (nr_packets > 0) {
 209                 pkt = pkt_alloc_packet_data();
 210                 if (!pkt) {
 211                         pkt_shrink_pktlist(pd);
 212                         return 0;
 213                 }
 214                 pkt->id = nr_packets;
 215                 pkt->pd = pd;
 216                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 217                 nr_packets--;
 218         }
 219         return 1;
 220 }
 221
 222 static void *pkt_rb_alloc(int gfp_mask, void *data)
 223 {
 224         return kmalloc(sizeof(struct pkt_rb_node), gfp_mask);
 225 }
 226
 227 static void pkt_rb_free(void *ptr, void *data)
 228 {
 229         kfree(ptr);
 230 }
 231
 232 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 233 {
 234         struct rb_node *n = rb_next(&node->rb_node);
 235         if (!n)
 236                 return NULL;
 237         return rb_entry(n, struct pkt_rb_node, rb_node);
 238 }
 239
 240 static inline void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 241 {
 242         rb_erase(&node->rb_node, &pd->bio_queue);
 243         mempool_free(node, pd->rb_pool);
 244         pd->bio_queue_size--;
 245         BUG_ON(pd->bio_queue_size < 0);
 246 }
 247
 248 /*
 249  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 250  */
 251 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 252 {
 253         struct rb_node *n = pd->bio_queue.rb_node;
 254         struct rb_node *next;
 255         struct pkt_rb_node *tmp;
 256
 257         if (!n) {
 258                 BUG_ON(pd->bio_queue_size > 0);
 259                 return NULL;
 260         }
 261
 262         for (;;) {
 263                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 264                 if (s <= tmp->bio->bi_sector)
 265                         next = n->rb_left;
 266                 else
 267                         next = n->rb_right;
 268                 if (!next)
 269                         break;
 270                 n = next;
 271         }
 272
 273         if (s > tmp->bio->bi_sector) {
 274                 tmp = pkt_rbtree_next(tmp);
 275                 if (!tmp)
 276                         return NULL;
 277         }
 278         BUG_ON(s > tmp->bio->bi_sector);
 279         return tmp;
 280 }
 281
 282 /*
 283  * Insert a node into the pd->bio_queue rb tree.
 284  */
 285 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 286 {
 287         struct rb_node **p = &pd->bio_queue.rb_node;
 288         struct rb_node *parent = NULL;
 289         sector_t s = node->bio->bi_sector;
 290         struct pkt_rb_node *tmp;
 291
 292         while (*p) {
 293                 parent = *p;
 294                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 295                 if (s < tmp->bio->bi_sector)
 296                         p = &(*p)->rb_left;
 297                 else
 298                         p = &(*p)->rb_right;
 299         }
 300         rb_link_node(&node->rb_node, parent, p);
 301         rb_insert_color(&node->rb_node, &pd->bio_queue);
 302         pd->bio_queue_size++;
 303 }
 304
 305 /*
 306  * Add a bio to a single linked list defined by its head and tail pointers.
 307  */
 308 static inline void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
 309 {
 310         bio->bi_next = NULL;
 311         if (*list_tail) {
 312                 BUG_ON((*list_head) == NULL);
 313                 (*list_tail)->bi_next = bio;
 314                 (*list_tail) = bio;
 315         } else {
 316                 BUG_ON((*list_head) != NULL);
 317                 (*list_head) = bio;
 318                 (*list_tail) = bio;
 319         }
 320 }
 321
 322 /*
 323  * Remove and return the first bio from a single linked list defined by its
 324  * head and tail pointers.
 325  */
 326 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
 327 {
 328         struct bio *bio;
 329
 330         if (*list_head == NULL)
 331                 return NULL;
 332
 333         bio = *list_head;
 334         *list_head = bio->bi_next;
 335         if (*list_head == NULL)
 336                 *list_tail = NULL;
 337
 338         bio->bi_next = NULL;
 339         return bio;
 340 }
 341
 342 /*
 343  * Send a packet_command to the underlying block device and
 344  * wait for completion.
 345  */
 346 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 347 {
 348         char sense[SCSI_SENSE_BUFFERSIZE];
 349         request_queue_t *q;
 350         struct request *rq;
 351         DECLARE_COMPLETION(wait);
 352         int err = 0;
 353
 354         q = bdev_get_queue(pd->bdev);
 355
 356         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ,
 357                              __GFP_WAIT);
 358         rq->errors = 0;
 359         rq->rq_disk = pd->bdev->bd_disk;
 360         rq->bio = NULL;
 361         rq->buffer = NULL;
 362         rq->timeout = 60*HZ;
 363         rq->data = cgc->buffer;
 364         rq->data_len = cgc->buflen;
 365         rq->sense = sense;
 366         memset(sense, 0, sizeof(sense));
 367         rq->sense_len = 0;
 368         rq->flags |= REQ_BLOCK_PC | REQ_HARDBARRIER;
 369         if (cgc->quiet)
 370                 rq->flags |= REQ_QUIET;
 371         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 372         if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
 373                 memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);
 374
 375         rq->ref_count++;
 376         rq->flags |= REQ_NOMERGE;
 377         rq->waiting = &wait;
 378         elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
 379         generic_unplug_device(q);
 380         wait_for_completion(&wait);
 381
 382         if (rq->errors)
 383                 err = -EIO;
 384
 385         blk_put_request(rq);
 386         return err;
 387 }
 388
 389 /*
 390  * A generic sense dump / resolve mechanism should be implemented across
 391  * all ATAPI + SCSI devices.
 392  */
 393 static void pkt_dump_sense(struct packet_command *cgc)
 394 {
 395         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 396                                  "Medium error", "Hardware error", "Illegal request",
 397                                  "Unit attention", "Data protect", "Blank check" };
 398         int i;
 399         struct request_sense *sense = cgc->sense;
 400
 401         printk("pktcdvd:");
 402         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 403                 printk(" %02x", cgc->cmd[i]);
 404         printk(" - ");
 405
 406         if (sense == NULL) {
 407                 printk("no sense\n");
 408                 return;
 409         }
 410
 411         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 412
 413         if (sense->sense_key > 8) {
 414                 printk(" (INVALID)\n");
 415                 return;
 416         }
 417
 418         printk(" (%s)\n", info[sense->sense_key]);
 419 }
 420
 421 /*
 422  * flush the drive cache to media
 423  */
 424 static int pkt_flush_cache(struct pktcdvd_device *pd)
 425 {
 426         struct packet_command cgc;
 427
 428         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 429         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 430         cgc.quiet = 1;
 431
 432         /*
 433          * the IMMED bit -- we default to not setting it, although that
 434          * would allow a much faster close, this is safer
 435          */
 436 #if 0
 437         cgc.cmd[1] = 1 << 1;
 438 #endif
 439         return pkt_generic_packet(pd, &cgc);
 440 }
 441
 442 /*
 443  * speed is given as the normal factor, e.g. 4 for 4x
 444  */
 445 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
 446 {
 447         struct packet_command cgc;
 448         struct request_sense sense;
 449         int ret;
 450
 451         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 452         cgc.sense = &sense;
 453         cgc.cmd[0] = GPCMD_SET_SPEED;
 454         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 455         cgc.cmd[3] = read_speed & 0xff;
 456         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 457         cgc.cmd[5] = write_speed & 0xff;
 458
 459         if ((ret = pkt_generic_packet(pd, &cgc)))
 460                 pkt_dump_sense(&cgc);
 461
 462         return ret;
 463 }
 464
 465 /*
 466  * Queue a bio for processing by the low-level CD device. Must be called
 467  * from process context.
 468  */
 469 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio, int high_prio_read)
 470 {
 471         spin_lock(&pd->iosched.lock);
 472         if (bio_data_dir(bio) == READ) {
 473                 pkt_add_list_last(bio, &pd->iosched.read_queue,
 474                                   &pd->iosched.read_queue_tail);
 475                 if (high_prio_read)
 476                         pd->iosched.high_prio_read = 1;
 477         } else {
 478                 pkt_add_list_last(bio, &pd->iosched.write_queue,
 479                                   &pd->iosched.write_queue_tail);
 480         }
 481         spin_unlock(&pd->iosched.lock);
 482
 483         atomic_set(&pd->iosched.attention, 1);
 484         wake_up(&pd->wqueue);
 485 }
 486
 487 /*
 488  * Process the queued read/write requests. This function handles special
 489  * requirements for CDRW drives:
 490  * - A cache flush command must be inserted before a read request if the
 491  *   previous request was a write.
 492  * - Switching between reading and writing is slow, so don't it more often
 493  *   than necessary.
 494  * - Set the read speed according to current usage pattern. When only reading
 495  *   from the device, it's best to use the highest possible read speed, but
 496  *   when switching often between reading and writing, it's better to have the
 497  *   same read and write speeds.
 498  * - Reads originating from user space should have higher priority than reads
 499  *   originating from pkt_gather_data, because some process is usually waiting
 500  *   on reads of the first kind.
 501  */
 502 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 503 {
 504         request_queue_t *q;
 505
 506         if (atomic_read(&pd->iosched.attention) == 0)
 507                 return;
 508         atomic_set(&pd->iosched.attention, 0);
 509
 510         q = bdev_get_queue(pd->bdev);
 511
 512         for (;;) {
 513                 struct bio *bio;
 514                 int reads_queued, writes_queued, high_prio_read;
 515
 516                 spin_lock(&pd->iosched.lock);
 517                 reads_queued = (pd->iosched.read_queue != NULL);
 518                 writes_queued = (pd->iosched.write_queue != NULL);
 519                 if (!reads_queued)
 520                         pd->iosched.high_prio_read = 0;
 521                 high_prio_read = pd->iosched.high_prio_read;
 522                 spin_unlock(&pd->iosched.lock);
 523
 524                 if (!reads_queued && !writes_queued)
 525                         break;
 526
 527                 if (pd->iosched.writing) {
 528                         if (high_prio_read || (!writes_queued && reads_queued)) {
 529                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 530                                         VPRINTK("pktcdvd: write, waiting\n");
 531                                         break;
 532                                 }
 533                                 pkt_flush_cache(pd);
 534                                 pd->iosched.writing = 0;
 535                         }
 536                 } else {
 537                         if (!reads_queued && writes_queued) {
 538                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 539                                         VPRINTK("pktcdvd: read, waiting\n");
 540                                         break;
 541                                 }
 542                                 pd->iosched.writing = 1;
 543                         }
 544                 }
 545
 546                 spin_lock(&pd->iosched.lock);
 547                 if (pd->iosched.writing) {
 548                         bio = pkt_get_list_first(&pd->iosched.write_queue,
 549                                                  &pd->iosched.write_queue_tail);
 550                 } else {
 551                         bio = pkt_get_list_first(&pd->iosched.read_queue,
 552                                                  &pd->iosched.read_queue_tail);
 553                 }
 554                 spin_unlock(&pd->iosched.lock);
 555
 556                 if (!bio)
 557                         continue;
 558
 559                 if (bio_data_dir(bio) == READ)
 560                         pd->iosched.successive_reads += bio->bi_size >> 10;
 561                 else
 562                         pd->iosched.successive_reads = 0;
 563                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 564                         if (pd->read_speed == pd->write_speed) {
 565                                 pd->read_speed = MAX_SPEED;
 566                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 567                         }
 568                 } else {
 569                         if (pd->read_speed != pd->write_speed) {
 570                                 pd->read_speed = pd->write_speed;
 571                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 572                         }
 573                 }
 574
 575                 atomic_inc(&pd->cdrw.pending_bios);
 576                 generic_make_request(bio);
 577         }
 578 }
 579
 580 /*
 581  * Special care is needed if the underlying block device has a small
 582  * max_phys_segments value.
 583  */
 584 static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
 585 {
 586         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 587                 /*
 588                  * The cdrom device can handle one segment/frame
 589                  */
 590                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 591                 return 0;
 592         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
 593                 /*
 594                  * We can handle this case at the expense of some extra memory
 595                  * copies during write operations
 596                  */
 597                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 598                 return 0;
 599         } else {
 600                 printk("pktcdvd: cdrom max_phys_segments too small\n");
 601                 return -EIO;
 602         }
 603 }
 604
 605 /*
 606  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 607  */
 608 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 609 {
 610         unsigned int copy_size = CD_FRAMESIZE;
 611
 612         while (copy_size > 0) {
 613                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 614                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 615                         src_bvl->bv_offset + offs;
 616                 void *vto = page_address(dst_page) + dst_offs;
 617                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 618
 619                 BUG_ON(len < 0);
 620                 memcpy(vto, vfrom, len);
 621                 kunmap_atomic(vfrom, KM_USER0);
 622
 623                 seg++;
 624                 offs = 0;
 625                 dst_offs += len;
 626                 copy_size -= len;
 627         }
 628 }
 629
 630 /*
 631  * Copy all data for this packet to pkt->pages[], so that
 632  * a) The number of required segments for the write bio is minimized, which
 633  *    is necessary for some scsi controllers.
 634  * b) The data can be used as cache to avoid read requests if we receive a
 635  *    new write request for the same zone.
 636  */
 637 static void pkt_make_local_copy(struct packet_data *pkt, struct page **pages, int *offsets)
 638 {
 639         int f, p, offs;
 640
 641         /* Copy all data to pkt->pages[] */
 642         p = 0;
 643         offs = 0;
 644         for (f = 0; f < pkt->frames; f++) {
 645                 if (pages[f] != pkt->pages[p]) {
 646                         void *vfrom = kmap_atomic(pages[f], KM_USER0) + offsets[f];
 647                         void *vto = page_address(pkt->pages[p]) + offs;
 648                         memcpy(vto, vfrom, CD_FRAMESIZE);
 649                         kunmap_atomic(vfrom, KM_USER0);
 650                         pages[f] = pkt->pages[p];
 651                         offsets[f] = offs;
 652                 } else {
 653                         BUG_ON(offsets[f] != offs);
 654                 }
 655                 offs += CD_FRAMESIZE;
 656                 if (offs >= PAGE_SIZE) {
 657                         BUG_ON(offs > PAGE_SIZE);
 658                         offs = 0;
 659                         p++;
 660                 }
 661         }
 662 }
 663
 664 static int pkt_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
 665 {
 666         struct packet_data *pkt = bio->bi_private;
 667         struct pktcdvd_device *pd = pkt->pd;
 668         BUG_ON(!pd);
 669
 670         if (bio->bi_size)
 671                 return 1;
 672
 673         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 674                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 675
 676         if (err)
 677                 atomic_inc(&pkt->io_errors);
 678         if (atomic_dec_and_test(&pkt->io_wait)) {
 679                 atomic_inc(&pkt->run_sm);
 680                 wake_up(&pd->wqueue);
 681         }
 682         pkt_bio_finished(pd);
 683
 684         return 0;
 685 }
 686
 687 static int pkt_end_io_packet_write(struct bio *bio, unsigned int bytes_done, int err)
 688 {
 689         struct packet_data *pkt = bio->bi_private;
 690         struct pktcdvd_device *pd = pkt->pd;
 691         BUG_ON(!pd);
 692
 693         if (bio->bi_size)
 694                 return 1;
 695
 696         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
 697
 698         pd->stats.pkt_ended++;
 699
 700         pkt_bio_finished(pd);
 701         atomic_dec(&pkt->io_wait);
 702         atomic_inc(&pkt->run_sm);
 703         wake_up(&pd->wqueue);
 704         return 0;
 705 }
 706
 707 /*
 708  * Schedule reads for the holes in a packet
 709  */
 710 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 711 {
 712         int frames_read = 0;
 713         struct bio *bio;
 714         int f;
 715         char written[PACKET_MAX_SIZE];
 716
 717         BUG_ON(!pkt->orig_bios);
 718
 719         atomic_set(&pkt->io_wait, 0);
 720         atomic_set(&pkt->io_errors, 0);
 721
 722         if (pkt->cache_valid) {
 723                 VPRINTK("pkt_gather_data: zone %llx cached\n",
 724                         (unsigned long long)pkt->sector);
 725                 goto out_account;
 726         }
 727
 728         /*
 729          * Figure out which frames we need to read before we can write.
 730          */
 731         memset(written, 0, sizeof(written));
 732         spin_lock(&pkt->lock);
 733         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
 734                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
 735                 int num_frames = bio->bi_size / CD_FRAMESIZE;
 736                 BUG_ON(first_frame < 0);
 737                 BUG_ON(first_frame + num_frames > pkt->frames);
 738                 for (f = first_frame; f < first_frame + num_frames; f++)
 739                         written[f] = 1;
 740         }
 741         spin_unlock(&pkt->lock);
 742
 743         /*
 744          * Schedule reads for missing parts of the packet.
 745          */
 746         for (f = 0; f < pkt->frames; f++) {
 747                 int p, offset;
 748                 if (written[f])
 749                         continue;
 750                 bio = pkt->r_bios[f];
 751                 bio_init(bio);
 752                 bio->bi_max_vecs = 1;
 753                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 754                 bio->bi_bdev = pd->bdev;
 755                 bio->bi_end_io = pkt_end_io_read;
 756                 bio->bi_private = pkt;
 757
 758                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
 759                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 760                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
 761                         f, pkt->pages[p], offset);
 762                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
 763                         BUG();
 764
 765                 atomic_inc(&pkt->io_wait);
 766                 bio->bi_rw = READ;
 767                 pkt_queue_bio(pd, bio, 0);
 768                 frames_read++;
 769         }
 770
 771 out_account:
 772         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
 773                 frames_read, (unsigned long long)pkt->sector);
 774         pd->stats.pkt_started++;
 775         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
 776         pd->stats.secs_w += pd->settings.size;
 777 }
 778
 779 /*
 780  * Find a packet matching zone, or the least recently used packet if
 781  * there is no match.
 782  */
 783 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
 784 {
 785         struct packet_data *pkt;
 786
 787         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
 788                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
 789                         list_del_init(&pkt->list);
 790                         if (pkt->sector != zone)
 791                                 pkt->cache_valid = 0;
 792                         break;
 793                 }
 794         }
 795         return pkt;
 796 }
 797
 798 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 799 {
 800         if (pkt->cache_valid) {
 801                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 802         } else {
 803                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
 804         }
 805 }
 806
 807 /*
 808  * recover a failed write, query for relocation if possible
 809  *
 810  * returns 1 if recovery is possible, or 0 if not
 811  *
 812  */
 813 static int pkt_start_recovery(struct packet_data *pkt)
 814 {
 815         /*
 816          * FIXME. We need help from the file system to implement
 817          * recovery handling.
 818          */
 819         return 0;
 820 #if 0
 821         struct request *rq = pkt->rq;
 822         struct pktcdvd_device *pd = rq->rq_disk->private_data;
 823         struct block_device *pkt_bdev;
 824         struct super_block *sb = NULL;
 825         unsigned long old_block, new_block;
 826         sector_t new_sector;
 827
 828         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
 829         if (pkt_bdev) {
 830                 sb = get_super(pkt_bdev);
 831                 bdput(pkt_bdev);
 832         }
 833
 834         if (!sb)
 835                 return 0;
 836
 837         if (!sb->s_op || !sb->s_op->relocate_blocks)
 838                 goto out;
 839
 840         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
 841         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
 842                 goto out;
 843
 844         new_sector = new_block * (CD_FRAMESIZE >> 9);
 845         pkt->sector = new_sector;
 846
 847         pkt->bio->bi_sector = new_sector;
 848         pkt->bio->bi_next = NULL;
 849         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
 850         pkt->bio->bi_idx = 0;
 851
 852         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
 853         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
 854         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
 855         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
 856         BUG_ON(pkt->bio->bi_private != pkt);
 857
 858         drop_super(sb);
 859         return 1;
 860
 861 out:
 862         drop_super(sb);
 863         return 0;
 864 #endif
 865 }
 866
 867 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
 868 {
 869 #if PACKET_DEBUG > 1
 870         static const char *state_name[] = {
 871                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
 872         };
 873         enum packet_data_state old_state = pkt->state;
 874         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
 875                 state_name[old_state], state_name[state]);
 876 #endif
 877         pkt->state = state;
 878 }
 879
 880 /*
 881  * Scan the work queue to see if we can start a new packet.
 882  * returns non-zero if any work was done.
 883  */
 884 static int pkt_handle_queue(struct pktcdvd_device *pd)
 885 {
 886         struct packet_data *pkt, *p;
 887         struct bio *bio = NULL;
 888         sector_t zone = 0; /* Suppress gcc warning */
 889         struct pkt_rb_node *node, *first_node;
 890         struct rb_node *n;
 891
 892         VPRINTK("handle_queue\n");
 893
 894         atomic_set(&pd->scan_queue, 0);
 895
 896         if (list_empty(&pd->cdrw.pkt_free_list)) {
 897                 VPRINTK("handle_queue: no pkt\n");
 898                 return 0;
 899         }
 900
 901         /*
 902          * Try to find a zone we are not already working on.
 903          */
 904         spin_lock(&pd->lock);
 905         first_node = pkt_rbtree_find(pd, pd->current_sector);
 906         if (!first_node) {
 907                 n = rb_first(&pd->bio_queue);
 908                 if (n)
 909                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
 910         }
 911         node = first_node;
 912         while (node) {
 913                 bio = node->bio;
 914                 zone = ZONE(bio->bi_sector, pd);
 915                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
 916                         if (p->sector == zone)
 917                                 goto try_next_bio;
 918                 }
 919                 break;
 920 try_next_bio:
 921                 node = pkt_rbtree_next(node);
 922                 if (!node) {
 923                         n = rb_first(&pd->bio_queue);
 924                         if (n)
 925                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
 926                 }
 927                 if (node == first_node)
 928                         node = NULL;
 929         }
 930         spin_unlock(&pd->lock);
 931         if (!bio) {
 932                 VPRINTK("handle_queue: no bio\n");
 933                 return 0;
 934         }
 935
 936         pkt = pkt_get_packet_data(pd, zone);
 937         BUG_ON(!pkt);
 938
 939         pd->current_sector = zone + pd->settings.size;
 940         pkt->sector = zone;
 941         pkt->frames = pd->settings.size >> 2;
 942         BUG_ON(pkt->frames > PACKET_MAX_SIZE);
 943         pkt->write_size = 0;
 944
 945         /*
 946          * Scan work queue for bios in the same zone and link them
 947          * to this packet.
 948          */
 949         spin_lock(&pd->lock);
 950         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
 951         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
 952                 bio = node->bio;
 953                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
 954                         (unsigned long long)ZONE(bio->bi_sector, pd));
 955                 if (ZONE(bio->bi_sector, pd) != zone)
 956                         break;
 957                 pkt_rbtree_erase(pd, node);
 958                 spin_lock(&pkt->lock);
 959                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
 960                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
 961                 spin_unlock(&pkt->lock);
 962         }
 963         spin_unlock(&pd->lock);
 964
 965         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
 966         pkt_set_state(pkt, PACKET_WAITING_STATE);
 967         atomic_set(&pkt->run_sm, 1);
 968
 969         spin_lock(&pd->cdrw.active_list_lock);
 970         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
 971         spin_unlock(&pd->cdrw.active_list_lock);
 972
 973         return 1;
 974 }
 975
 976 /*
 977  * Assemble a bio to write one packet and queue the bio for processing
 978  * by the underlying block device.
 979  */
 980 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 981 {
 982         struct bio *bio;
 983         struct page *pages[PACKET_MAX_SIZE];
 984         int offsets[PACKET_MAX_SIZE];
 985         int f;
 986         int frames_write;
 987
 988         for (f = 0; f < pkt->frames; f++) {
 989                 pages[f] = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
 990                 offsets[f] = (f * CD_FRAMESIZE) % PAGE_SIZE;
 991         }
 992
 993         /*
 994          * Fill-in pages[] and offsets[] with data from orig_bios.
 995          */
 996         frames_write = 0;
 997         spin_lock(&pkt->lock);
 998         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
 999                 int segment = bio->bi_idx;
1000                 int src_offs = 0;
1001                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1002                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1003                 BUG_ON(first_frame < 0);
1004                 BUG_ON(first_frame + num_frames > pkt->frames);
1005                 for (f = first_frame; f < first_frame + num_frames; f++) {
1006                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1007
1008                         while (src_offs >= src_bvl->bv_len) {
1009                                 src_offs -= src_bvl->bv_len;
1010                                 segment++;
1011                                 BUG_ON(segment >= bio->bi_vcnt);
1012                                 src_bvl = bio_iovec_idx(bio, segment);
1013                         }
1014
1015                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1016                                 pages[f] = src_bvl->bv_page;
1017                                 offsets[f] = src_bvl->bv_offset + src_offs;
1018                         } else {
1019                                 pkt_copy_bio_data(bio, segment, src_offs,
1020                                                   pages[f], offsets[f]);
1021                         }
1022                         src_offs += CD_FRAMESIZE;
1023                         frames_write++;
1024                 }
1025         }
1026         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1027         spin_unlock(&pkt->lock);
1028
1029         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1030                 frames_write, (unsigned long long)pkt->sector);
1031         BUG_ON(frames_write != pkt->write_size);
1032
1033         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1034                 pkt_make_local_copy(pkt, pages, offsets);
1035                 pkt->cache_valid = 1;
1036         } else {
1037                 pkt->cache_valid = 0;
1038         }
1039
1040         /* Start the write request */
1041         bio_init(pkt->w_bio);
1042         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1043         pkt->w_bio->bi_sector = pkt->sector;
1044         pkt->w_bio->bi_bdev = pd->bdev;
1045         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1046         pkt->w_bio->bi_private = pkt;
1047         for (f = 0; f < pkt->frames; f++) {
1048                 if ((f + 1 < pkt->frames) && (pages[f + 1] == pages[f]) &&
1049                     (offsets[f + 1] = offsets[f] + CD_FRAMESIZE)) {
1050                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE * 2, offsets[f]))
1051                                 BUG();
1052                         f++;
1053                 } else {
1054                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE, offsets[f]))
1055                                 BUG();
1056                 }
1057         }
1058         VPRINTK("pktcdvd: vcnt=%d\n", pkt->w_bio->bi_vcnt);
1059
1060         atomic_set(&pkt->io_wait, 1);
1061         pkt->w_bio->bi_rw = WRITE;
1062         pkt_queue_bio(pd, pkt->w_bio, 0);
1063 }
1064
1065 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1066 {
1067         struct bio *bio, *next;
1068
1069         if (!uptodate)
1070                 pkt->cache_valid = 0;
1071
1072         /* Finish all bios corresponding to this packet */
1073         bio = pkt->orig_bios;
1074         while (bio) {
1075                 next = bio->bi_next;
1076                 bio->bi_next = NULL;
1077                 bio_endio(bio, bio->bi_size, uptodate ? 0 : -EIO);
1078                 bio = next;
1079         }
1080         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1081 }
1082
1083 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1084 {
1085         int uptodate;
1086
1087         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1088
1089         for (;;) {
1090                 switch (pkt->state) {
1091                 case PACKET_WAITING_STATE:
1092                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1093                                 return;
1094
1095                         pkt->sleep_time = 0;
1096                         pkt_gather_data(pd, pkt);
1097                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1098                         break;
1099
1100                 case PACKET_READ_WAIT_STATE:
1101                         if (atomic_read(&pkt->io_wait) > 0)
1102                                 return;
1103
1104                         if (atomic_read(&pkt->io_errors) > 0) {
1105                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1106                         } else {
1107                                 pkt_start_write(pd, pkt);
1108                         }
1109                         break;
1110
1111                 case PACKET_WRITE_WAIT_STATE:
1112                         if (atomic_read(&pkt->io_wait) > 0)
1113                                 return;
1114
1115                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1116                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1117                         } else {
1118                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1119                         }
1120                         break;
1121
1122                 case PACKET_RECOVERY_STATE:
1123                         if (pkt_start_recovery(pkt)) {
1124                                 pkt_start_write(pd, pkt);
1125                         } else {
1126                                 VPRINTK("No recovery possible\n");
1127                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1128                         }
1129                         break;
1130
1131                 case PACKET_FINISHED_STATE:
1132                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1133                         pkt_finish_packet(pkt, uptodate);
1134                         return;
1135
1136                 default:
1137                         BUG();
1138                         break;
1139                 }
1140         }
1141 }
1142
1143 static void pkt_handle_packets(struct pktcdvd_device *pd)
1144 {
1145         struct packet_data *pkt, *next;
1146
1147         VPRINTK("pkt_handle_packets\n");
1148
1149         /*
1150          * Run state machine for active packets
1151          */
1152         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1153                 if (atomic_read(&pkt->run_sm) > 0) {
1154                         atomic_set(&pkt->run_sm, 0);
1155                         pkt_run_state_machine(pd, pkt);
1156                 }
1157         }
1158
1159         /*
1160          * Move no longer active packets to the free list
1161          */
1162         spin_lock(&pd->cdrw.active_list_lock);
1163         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1164                 if (pkt->state == PACKET_FINISHED_STATE) {
1165                         list_del(&pkt->list);
1166                         pkt_put_packet_data(pd, pkt);
1167                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1168                         atomic_set(&pd->scan_queue, 1);
1169                 }
1170         }
1171         spin_unlock(&pd->cdrw.active_list_lock);
1172 }
1173
1174 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1175 {
1176         struct packet_data *pkt;
1177         int i;
1178
1179         for (i = 0; i <= PACKET_NUM_STATES; i++)
1180                 states[i] = 0;
1181
1182         spin_lock(&pd->cdrw.active_list_lock);
1183         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1184                 states[pkt->state]++;
1185         }
1186         spin_unlock(&pd->cdrw.active_list_lock);
1187 }
1188
1189 /*
1190  * kcdrwd is woken up when writes have been queued for one of our
1191  * registered devices
1192  */
1193 static int kcdrwd(void *foobar)
1194 {
1195         struct pktcdvd_device *pd = foobar;
1196         struct packet_data *pkt;
1197         long min_sleep_time, residue;
1198
1199         set_user_nice(current, -20);
1200
1201         for (;;) {
1202                 DECLARE_WAITQUEUE(wait, current);
1203
1204                 /*
1205                  * Wait until there is something to do
1206                  */
1207                 add_wait_queue(&pd->wqueue, &wait);
1208                 for (;;) {
1209                         set_current_state(TASK_INTERRUPTIBLE);
1210
1211                         /* Check if we need to run pkt_handle_queue */
1212                         if (atomic_read(&pd->scan_queue) > 0)
1213                                 goto work_to_do;
1214
1215                         /* Check if we need to run the state machine for some packet */
1216                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1217                                 if (atomic_read(&pkt->run_sm) > 0)
1218                                         goto work_to_do;
1219                         }
1220
1221                         /* Check if we need to process the iosched queues */
1222                         if (atomic_read(&pd->iosched.attention) != 0)
1223                                 goto work_to_do;
1224
1225                         /* Otherwise, go to sleep */
1226                         if (PACKET_DEBUG > 1) {
1227                                 int states[PACKET_NUM_STATES];
1228                                 pkt_count_states(pd, states);
1229                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1230                                         states[0], states[1], states[2], states[3],
1231                                         states[4], states[5]);
1232                         }
1233
1234                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1235                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1236                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1237                                         min_sleep_time = pkt->sleep_time;
1238                         }
1239
1240                         generic_unplug_device(bdev_get_queue(pd->bdev));
1241
1242                         VPRINTK("kcdrwd: sleeping\n");
1243                         residue = schedule_timeout(min_sleep_time);
1244                         VPRINTK("kcdrwd: wake up\n");
1245
1246                         /* make swsusp happy with our thread */
1247                         if (current->flags & PF_FREEZE)
1248                                 refrigerator(PF_FREEZE);
1249
1250                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1251                                 if (!pkt->sleep_time)
1252                                         continue;
1253                                 pkt->sleep_time -= min_sleep_time - residue;
1254                                 if (pkt->sleep_time <= 0) {
1255                                         pkt->sleep_time = 0;
1256                                         atomic_inc(&pkt->run_sm);
1257                                 }
1258                         }
1259
1260                         if (signal_pending(current)) {
1261                                 flush_signals(current);
1262                         }
1263                         if (kthread_should_stop())
1264                                 break;
1265                 }
1266 work_to_do:
1267                 set_current_state(TASK_RUNNING);
1268                 remove_wait_queue(&pd->wqueue, &wait);
1269
1270                 if (kthread_should_stop())
1271                         break;
1272
1273                 /*
1274                  * if pkt_handle_queue returns true, we can queue
1275                  * another request.
1276                  */
1277                 while (pkt_handle_queue(pd))
1278                         ;
1279
1280                 /*
1281                  * Handle packet state machine
1282                  */
1283                 pkt_handle_packets(pd);
1284
1285                 /*
1286                  * Handle iosched queues
1287                  */
1288                 pkt_iosched_process_queue(pd);
1289         }
1290
1291         return 0;
1292 }
1293
1294 static void pkt_print_settings(struct pktcdvd_device *pd)
1295 {
1296         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1297         printk("%u blocks, ", pd->settings.size >> 2);
1298         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1299 }
1300
1301 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1302 {
1303         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1304
1305         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1306         cgc->cmd[2] = page_code | (page_control << 6);
1307         cgc->cmd[7] = cgc->buflen >> 8;
1308         cgc->cmd[8] = cgc->buflen & 0xff;
1309         cgc->data_direction = CGC_DATA_READ;
1310         return pkt_generic_packet(pd, cgc);
1311 }
1312
1313 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1314 {
1315         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1316         memset(cgc->buffer, 0, 2);
1317         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1318         cgc->cmd[1] = 0x10;             /* PF */
1319         cgc->cmd[7] = cgc->buflen >> 8;
1320         cgc->cmd[8] = cgc->buflen & 0xff;
1321         cgc->data_direction = CGC_DATA_WRITE;
1322         return pkt_generic_packet(pd, cgc);
1323 }
1324
1325 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1326 {
1327         struct packet_command cgc;
1328         int ret;
1329
1330         /* set up command and get the disc info */
1331         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1332         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1333         cgc.cmd[8] = cgc.buflen = 2;
1334         cgc.quiet = 1;
1335
1336         if ((ret = pkt_generic_packet(pd, &cgc)))
1337                 return ret;
1338
1339         /* not all drives have the same disc_info length, so requeue
1340          * packet with the length the drive tells us it can supply
1341          */
1342         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1343                      sizeof(di->disc_information_length);
1344
1345         if (cgc.buflen > sizeof(disc_information))
1346                 cgc.buflen = sizeof(disc_information);
1347
1348         cgc.cmd[8] = cgc.buflen;
1349         return pkt_generic_packet(pd, &cgc);
1350 }
1351
1352 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1353 {
1354         struct packet_command cgc;
1355         int ret;
1356
1357         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1358         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1359         cgc.cmd[1] = type & 3;
1360         cgc.cmd[4] = (track & 0xff00) >> 8;
1361         cgc.cmd[5] = track & 0xff;
1362         cgc.cmd[8] = 8;
1363         cgc.quiet = 1;
1364
1365         if ((ret = pkt_generic_packet(pd, &cgc)))
1366                 return ret;
1367
1368         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1369                      sizeof(ti->track_information_length);
1370
1371         if (cgc.buflen > sizeof(track_information))
1372                 cgc.buflen = sizeof(track_information);
1373
1374         cgc.cmd[8] = cgc.buflen;
1375         return pkt_generic_packet(pd, &cgc);
1376 }
1377
1378 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1379 {
1380         disc_information di;
1381         track_information ti;
1382         __u32 last_track;
1383         int ret = -1;
1384
1385         if ((ret = pkt_get_disc_info(pd, &di)))
1386                 return ret;
1387
1388         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1389         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1390                 return ret;
1391
1392         /* if this track is blank, try the previous. */
1393         if (ti.blank) {
1394                 last_track--;
1395                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1396                         return ret;
1397         }
1398
1399         /* if last recorded field is valid, return it. */
1400         if (ti.lra_v) {
1401                 *last_written = be32_to_cpu(ti.last_rec_address);
1402         } else {
1403                 /* make it up instead */
1404                 *last_written = be32_to_cpu(ti.track_start) +
1405                                 be32_to_cpu(ti.track_size);
1406                 if (ti.free_blocks)
1407                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1408         }
1409         return 0;
1410 }
1411
1412 /*
1413  * write mode select package based on pd->settings
1414  */
1415 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1416 {
1417         struct packet_command cgc;
1418         struct request_sense sense;
1419         write_param_page *wp;
1420         char buffer[128];
1421         int ret, size;
1422
1423         /* doesn't apply to DVD+RW */
1424         if (pd->mmc3_profile == 0x1a)
1425                 return 0;
1426
1427         memset(buffer, 0, sizeof(buffer));
1428         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1429         cgc.sense = &sense;
1430         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1431                 pkt_dump_sense(&cgc);
1432                 return ret;
1433         }
1434
1435         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1436         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1437         if (size > sizeof(buffer))
1438                 size = sizeof(buffer);
1439
1440         /*
1441          * now get it all
1442          */
1443         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1444         cgc.sense = &sense;
1445         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1446                 pkt_dump_sense(&cgc);
1447                 return ret;
1448         }
1449
1450         /*
1451          * write page is offset header + block descriptor length
1452          */
1453         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1454
1455         wp->fp = pd->settings.fp;
1456         wp->track_mode = pd->settings.track_mode;
1457         wp->write_type = pd->settings.write_type;
1458         wp->data_block_type = pd->settings.block_mode;
1459
1460         wp->multi_session = 0;
1461
1462 #ifdef PACKET_USE_LS
1463         wp->link_size = 7;
1464         wp->ls_v = 1;
1465 #endif
1466
1467         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1468                 wp->session_format = 0;
1469                 wp->subhdr2 = 0x20;
1470         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1471                 wp->session_format = 0x20;
1472                 wp->subhdr2 = 8;
1473 #if 0
1474                 wp->mcn[0] = 0x80;
1475                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1476 #endif
1477         } else {
1478                 /*
1479                  * paranoia
1480                  */
1481                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1482                 return 1;
1483         }
1484         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1485
1486         cgc.buflen = cgc.cmd[8] = size;
1487         if ((ret = pkt_mode_select(pd, &cgc))) {
1488                 pkt_dump_sense(&cgc);
1489                 return ret;
1490         }
1491
1492         pkt_print_settings(pd);
1493         return 0;
1494 }
1495
1496 /*
1497  * 0 -- we can write to this track, 1 -- we can't
1498  */
1499 static int pkt_good_track(track_information *ti)
1500 {
1501         /*
1502          * only good for CD-RW at the moment, not DVD-RW
1503          */
1504
1505         /*
1506          * FIXME: only for FP
1507          */
1508         if (ti->fp == 0)
1509                 return 0;
1510
1511         /*
1512          * "good" settings as per Mt Fuji.
1513          */
1514         if (ti->rt == 0 && ti->blank == 0 && ti->packet == 1)
1515                 return 0;
1516
1517         if (ti->rt == 0 && ti->blank == 1 && ti->packet == 1)
1518                 return 0;
1519
1520         if (ti->rt == 1 && ti->blank == 0 && ti->packet == 1)
1521                 return 0;
1522
1523         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1524         return 1;
1525 }
1526
1527 /*
1528  * 0 -- we can write to this disc, 1 -- we can't
1529  */
1530 static int pkt_good_disc(struct pktcdvd_device *pd, disc_information *di)
1531 {
1532         switch (pd->mmc3_profile) {
1533                 case 0x0a: /* CD-RW */
1534                 case 0xffff: /* MMC3 not supported */
1535                         break;
1536                 case 0x1a: /* DVD+RW */
1537                 case 0x13: /* DVD-RW */
1538                         return 0;
1539                 default:
1540                         printk("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1541                         return 1;
1542         }
1543
1544         /*
1545          * for disc type 0xff we should probably reserve a new track.
1546          * but i'm not sure, should we leave this to user apps? probably.
1547          */
1548         if (di->disc_type == 0xff) {
1549                 printk("pktcdvd: Unknown disc. No track?\n");
1550                 return 1;
1551         }
1552
1553         if (di->disc_type != 0x20 && di->disc_type != 0) {
1554                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1555                 return 1;
1556         }
1557
1558         if (di->erasable == 0) {
1559                 printk("pktcdvd: Disc not erasable\n");
1560                 return 1;
1561         }
1562
1563         if (di->border_status == PACKET_SESSION_RESERVED) {
1564                 printk("pktcdvd: Can't write to last track (reserved)\n");
1565                 return 1;
1566         }
1567
1568         return 0;
1569 }
1570
1571 static int pkt_probe_settings(struct pktcdvd_device *pd)
1572 {
1573         struct packet_command cgc;
1574         unsigned char buf[12];
1575         disc_information di;
1576         track_information ti;
1577         int ret, track;
1578
1579         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1580         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1581         cgc.cmd[8] = 8;
1582         ret = pkt_generic_packet(pd, &cgc);
1583         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1584
1585         memset(&di, 0, sizeof(disc_information));
1586         memset(&ti, 0, sizeof(track_information));
1587
1588         if ((ret = pkt_get_disc_info(pd, &di))) {
1589                 printk("failed get_disc\n");
1590                 return ret;
1591         }
1592
1593         if (pkt_good_disc(pd, &di))
1594                 return -ENXIO;
1595
1596         switch (pd->mmc3_profile) {
1597                 case 0x1a: /* DVD+RW */
1598                         printk("pktcdvd: inserted media is DVD+RW\n");
1599                         break;
1600                 case 0x13: /* DVD-RW */
1601                         printk("pktcdvd: inserted media is DVD-RW\n");
1602                         break;
1603                 default:
1604                         printk("pktcdvd: inserted media is CD-R%s\n", di.erasable ? "W" : "");
1605                         break;
1606         }
1607         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1608
1609         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1610         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1611                 printk("pktcdvd: failed get_track\n");
1612                 return ret;
1613         }
1614
1615         if (pkt_good_track(&ti)) {
1616                 printk("pktcdvd: can't write to this track\n");
1617                 return -ENXIO;
1618         }
1619
1620         /*
1621          * we keep packet size in 512 byte units, makes it easier to
1622          * deal with request calculations.
1623          */
1624         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1625         if (pd->settings.size == 0) {
1626                 printk("pktcdvd: detected zero packet size!\n");
1627                 pd->settings.size = 128;
1628         }
1629         pd->settings.fp = ti.fp;
1630         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1631
1632         if (ti.nwa_v) {
1633                 pd->nwa = be32_to_cpu(ti.next_writable);
1634                 set_bit(PACKET_NWA_VALID, &pd->flags);
1635         }
1636
1637         /*
1638          * in theory we could use lra on -RW media as well and just zero
1639          * blocks that haven't been written yet, but in practice that
1640          * is just a no-go. we'll use that for -R, naturally.
1641          */
1642         if (ti.lra_v) {
1643                 pd->lra = be32_to_cpu(ti.last_rec_address);
1644                 set_bit(PACKET_LRA_VALID, &pd->flags);
1645         } else {
1646                 pd->lra = 0xffffffff;
1647                 set_bit(PACKET_LRA_VALID, &pd->flags);
1648         }
1649
1650         /*
1651          * fine for now
1652          */
1653         pd->settings.link_loss = 7;
1654         pd->settings.write_type = 0;    /* packet */
1655         pd->settings.track_mode = ti.track_mode;
1656
1657         /*
1658          * mode1 or mode2 disc
1659          */
1660         switch (ti.data_mode) {
1661                 case PACKET_MODE1:
1662                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1663                         break;
1664                 case PACKET_MODE2:
1665                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1666                         break;
1667                 default:
1668                         printk("pktcdvd: unknown data mode\n");
1669                         return 1;
1670         }
1671         return 0;
1672 }
1673
1674 /*
1675  * enable/disable write caching on drive
1676  */
1677 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1678 {
1679         struct packet_command cgc;
1680         struct request_sense sense;
1681         unsigned char buf[64];
1682         int ret;
1683
1684         memset(buf, 0, sizeof(buf));
1685         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1686         cgc.sense = &sense;
1687         cgc.buflen = pd->mode_offset + 12;
1688
1689         /*
1690          * caching mode page might not be there, so quiet this command
1691          */
1692         cgc.quiet = 1;
1693
1694         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1695                 return ret;
1696
1697         buf[pd->mode_offset + 10] |= (!!set << 2);
1698
1699         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1700         ret = pkt_mode_select(pd, &cgc);
1701         if (ret) {
1702                 printk("pktcdvd: write caching control failed\n");
1703                 pkt_dump_sense(&cgc);
1704         } else if (!ret && set)
1705                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1706         return ret;
1707 }
1708
1709 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1710 {
1711         struct packet_command cgc;
1712
1713         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1714         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1715         cgc.cmd[4] = lockflag ? 1 : 0;
1716         return pkt_generic_packet(pd, &cgc);
1717 }
1718
1719 /*
1720  * Returns drive maximum write speed
1721  */
1722 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1723 {
1724         struct packet_command cgc;
1725         struct request_sense sense;
1726         unsigned char buf[256+18];
1727         unsigned char *cap_buf;
1728         int ret, offset;
1729
1730         memset(buf, 0, sizeof(buf));
1731         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1732         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1733         cgc.sense = &sense;
1734
1735         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1736         if (ret) {
1737                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1738                              sizeof(struct mode_page_header);
1739                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1740                 if (ret) {
1741                         pkt_dump_sense(&cgc);
1742                         return ret;
1743                 }
1744         }
1745
1746         offset = 20;                        /* Obsoleted field, used by older drives */
1747         if (cap_buf[1] >= 28)
1748                 offset = 28;                /* Current write speed selected */
1749         if (cap_buf[1] >= 30) {
1750                 /* If the drive reports at least one "Logical Unit Write
1751                  * Speed Performance Descriptor Block", use the information
1752                  * in the first block. (contains the highest speed)
1753                  */
1754                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1755                 if (num_spdb > 0)
1756                         offset = 34;
1757         }
1758
1759         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1760         return 0;
1761 }
1762
1763 /* These tables from cdrecord - I don't have orange book */
1764 /* standard speed CD-RW (1-4x) */
1765 static char 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, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1768 };
1769 /* high speed CD-RW (-10x) */
1770 static char hs_clv_to_speed[16] = {
1771         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1772            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1773 };
1774 /* ultra high speed CD-RW */
1775 static char us_clv_to_speed[16] = {
1776         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1777            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1778 };
1779
1780 /*
1781  * reads the maximum media speed from ATIP
1782  */
1783 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1784 {
1785         struct packet_command cgc;
1786         struct request_sense sense;
1787         unsigned char buf[64];
1788         unsigned int size, st, sp;
1789         int ret;
1790
1791         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1792         cgc.sense = &sense;
1793         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1794         cgc.cmd[1] = 2;
1795         cgc.cmd[2] = 4; /* READ ATIP */
1796         cgc.cmd[8] = 2;
1797         ret = pkt_generic_packet(pd, &cgc);
1798         if (ret) {
1799                 pkt_dump_sense(&cgc);
1800                 return ret;
1801         }
1802         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1803         if (size > sizeof(buf))
1804                 size = sizeof(buf);
1805
1806         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1807         cgc.sense = &sense;
1808         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1809         cgc.cmd[1] = 2;
1810         cgc.cmd[2] = 4;
1811         cgc.cmd[8] = size;
1812         ret = pkt_generic_packet(pd, &cgc);
1813         if (ret) {
1814                 pkt_dump_sense(&cgc);
1815                 return ret;
1816         }
1817
1818         if (!buf[6] & 0x40) {
1819                 printk("pktcdvd: Disc type is not CD-RW\n");
1820                 return 1;
1821         }
1822         if (!buf[6] & 0x4) {
1823                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1824                 return 1;
1825         }
1826
1827         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1828
1829         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1830
1831         /* Info from cdrecord */
1832         switch (st) {
1833                 case 0: /* standard speed */
1834                         *speed = clv_to_speed[sp];
1835                         break;
1836                 case 1: /* high speed */
1837                         *speed = hs_clv_to_speed[sp];
1838                         break;
1839                 case 2: /* ultra high speed */
1840                         *speed = us_clv_to_speed[sp];
1841                         break;
1842                 default:
1843                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1844                         return 1;
1845         }
1846         if (*speed) {
1847                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1848                 return 0;
1849         } else {
1850                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1851                 return 1;
1852         }
1853 }
1854
1855 static int pkt_perform_opc(struct pktcdvd_device *pd)
1856 {
1857         struct packet_command cgc;
1858         struct request_sense sense;
1859         int ret;
1860
1861         VPRINTK("pktcdvd: Performing OPC\n");
1862
1863         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1864         cgc.sense = &sense;
1865         cgc.timeout = 60*HZ;
1866         cgc.cmd[0] = GPCMD_SEND_OPC;
1867         cgc.cmd[1] = 1;
1868         if ((ret = pkt_generic_packet(pd, &cgc)))
1869                 pkt_dump_sense(&cgc);
1870         return ret;
1871 }
1872
1873 static int pkt_open_write(struct pktcdvd_device *pd)
1874 {
1875         int ret;
1876         unsigned int write_speed, media_write_speed, read_speed;
1877
1878         if ((ret = pkt_probe_settings(pd))) {
1879                 DPRINTK("pktcdvd: %s failed probe\n", pd->name);
1880                 return -EIO;
1881         }
1882
1883         if ((ret = pkt_set_write_settings(pd))) {
1884                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1885                 return -EIO;
1886         }
1887
1888         pkt_write_caching(pd, USE_WCACHING);
1889
1890         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1891                 write_speed = 16 * 177;
1892         switch (pd->mmc3_profile) {
1893                 case 0x13: /* DVD-RW */
1894                 case 0x1a: /* DVD+RW */
1895                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1896                         break;
1897                 default:
1898                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1899                                 media_write_speed = 16;
1900                         write_speed = min(write_speed, media_write_speed * 177);
1901                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1902                         break;
1903         }
1904         read_speed = write_speed;
1905
1906         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1907                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1908                 return -EIO;
1909         }
1910         pd->write_speed = write_speed;
1911         pd->read_speed = read_speed;
1912
1913         if ((ret = pkt_perform_opc(pd))) {
1914                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1915         }
1916
1917         return 0;
1918 }
1919
1920 /*
1921  * called at open time.
1922  */
1923 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1924 {
1925         int ret;
1926         long lba;
1927         request_queue_t *q;
1928
1929         /*
1930          * We need to re-open the cdrom device without O_NONBLOCK to be able
1931          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1932          * so bdget() can't fail.
1933          */
1934         bdget(pd->bdev->bd_dev);
1935         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1936                 goto out;
1937
1938         if ((ret = pkt_get_last_written(pd, &lba))) {
1939                 printk("pktcdvd: pkt_get_last_written failed\n");
1940                 goto out_putdev;
1941         }
1942
1943         set_capacity(pd->disk, lba << 2);
1944         set_capacity(pd->bdev->bd_disk, lba << 2);
1945         bd_set_size(pd->bdev, (loff_t)lba << 11);
1946
1947         q = bdev_get_queue(pd->bdev);
1948         if (write) {
1949                 if ((ret = pkt_open_write(pd)))
1950                         goto out_putdev;
1951                 /*
1952                  * Some CDRW drives can not handle writes larger than one packet,
1953                  * even if the size is a multiple of the packet size.
1954                  */
1955                 spin_lock_irq(q->queue_lock);
1956                 blk_queue_max_sectors(q, pd->settings.size);
1957                 spin_unlock_irq(q->queue_lock);
1958                 set_bit(PACKET_WRITABLE, &pd->flags);
1959         } else {
1960                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1961                 clear_bit(PACKET_WRITABLE, &pd->flags);
1962         }
1963
1964         if ((ret = pkt_set_segment_merging(pd, q)))
1965                 goto out_putdev;
1966
1967         if (write)
1968                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1969
1970         return 0;
1971
1972 out_putdev:
1973         blkdev_put(pd->bdev);
1974 out:
1975         return ret;
1976 }
1977
1978 /*
1979  * called when the device is closed. makes sure that the device flushes
1980  * the internal cache before we close.
1981  */
1982 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
1983 {
1984         if (flush && pkt_flush_cache(pd))
1985                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
1986
1987         pkt_lock_door(pd, 0);
1988
1989         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1990         blkdev_put(pd->bdev);
1991 }
1992
1993 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
1994 {
1995         if (dev_minor >= MAX_WRITERS)
1996                 return NULL;
1997         return pkt_devs[dev_minor];
1998 }
1999
2000 static int pkt_open(struct inode *inode, struct file *file)
2001 {
2002         struct pktcdvd_device *pd = NULL;
2003         int ret;
2004
2005         VPRINTK("pktcdvd: entering open\n");
2006
2007         down(&ctl_mutex);
2008         pd = pkt_find_dev_from_minor(iminor(inode));
2009         if (!pd) {
2010                 ret = -ENODEV;
2011                 goto out;
2012         }
2013         BUG_ON(pd->refcnt < 0);
2014
2015         pd->refcnt++;
2016         if (pd->refcnt == 1) {
2017                 if (pkt_open_dev(pd, file->f_mode & FMODE_WRITE)) {
2018                         ret = -EIO;
2019                         goto out_dec;
2020                 }
2021                 /*
2022                  * needed here as well, since ext2 (among others) may change
2023                  * the blocksize at mount time
2024                  */
2025                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2026         }
2027
2028         up(&ctl_mutex);
2029         return 0;
2030
2031 out_dec:
2032         pd->refcnt--;
2033 out:
2034         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2035         up(&ctl_mutex);
2036         return ret;
2037 }
2038
2039 static int pkt_close(struct inode *inode, struct file *file)
2040 {
2041         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2042         int ret = 0;
2043
2044         down(&ctl_mutex);
2045         pd->refcnt--;
2046         BUG_ON(pd->refcnt < 0);
2047         if (pd->refcnt == 0) {
2048                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2049                 pkt_release_dev(pd, flush);
2050         }
2051         up(&ctl_mutex);
2052         return ret;
2053 }
2054
2055
2056 static void *psd_pool_alloc(int gfp_mask, void *data)
2057 {
2058         return kmalloc(sizeof(struct packet_stacked_data), gfp_mask);
2059 }
2060
2061 static void psd_pool_free(void *ptr, void *data)
2062 {
2063         kfree(ptr);
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, 1);
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         BUG_ON(!node);
2185         node->bio = bio;
2186         spin_lock(&pd->lock);
2187         BUG_ON(pd->bio_queue_size < 0);
2188         was_empty = (pd->bio_queue_size == 0);
2189         pkt_rbtree_insert(pd, node);
2190         spin_unlock(&pd->lock);
2191
2192         /*
2193          * Wake up the worker thread.
2194          */
2195         atomic_set(&pd->scan_queue, 1);
2196         if (was_empty) {
2197                 /* This wake_up is required for correct operation */
2198                 wake_up(&pd->wqueue);
2199         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2200                 /*
2201                  * This wake up is not required for correct operation,
2202                  * but improves performance in some cases.
2203                  */
2204                 wake_up(&pd->wqueue);
2205         }
2206         return 0;
2207 end_io:
2208         bio_io_error(bio, bio->bi_size);
2209         return 0;
2210 }
2211
2212
2213
2214 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2215 {
2216         struct pktcdvd_device *pd = q->queuedata;
2217         sector_t zone = ZONE(bio->bi_sector, pd);
2218         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2219         int remaining = (pd->settings.size << 9) - used;
2220         int remaining2;
2221
2222         /*
2223          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2224          * boundary, pkt_make_request() will split the bio.
2225          */
2226         remaining2 = PAGE_SIZE - bio->bi_size;
2227         remaining = max(remaining, remaining2);
2228
2229         BUG_ON(remaining < 0);
2230         return remaining;
2231 }
2232
2233 static void pkt_init_queue(struct pktcdvd_device *pd)
2234 {
2235         request_queue_t *q = pd->disk->queue;
2236
2237         blk_queue_make_request(q, pkt_make_request);
2238         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2239         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2240         blk_queue_merge_bvec(q, pkt_merge_bvec);
2241         q->queuedata = pd;
2242 }
2243
2244 static int pkt_seq_show(struct seq_file *m, void *p)
2245 {
2246         struct pktcdvd_device *pd = m->private;
2247         char *msg;
2248         char bdev_buf[BDEVNAME_SIZE];
2249         int states[PACKET_NUM_STATES];
2250
2251         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2252                    bdevname(pd->bdev, bdev_buf));
2253
2254         seq_printf(m, "\nSettings:\n");
2255         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2256
2257         if (pd->settings.write_type == 0)
2258                 msg = "Packet";
2259         else
2260                 msg = "Unknown";
2261         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2262
2263         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2264         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2265
2266         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2267
2268         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2269                 msg = "Mode 1";
2270         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2271                 msg = "Mode 2";
2272         else
2273                 msg = "Unknown";
2274         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2275
2276         seq_printf(m, "\nStatistics:\n");
2277         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2278         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2279         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2280         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2281         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2282
2283         seq_printf(m, "\nMisc:\n");
2284         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2285         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2286         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2287         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2288         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2289         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2290
2291         seq_printf(m, "\nQueue state:\n");
2292         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2293         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2294         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2295
2296         pkt_count_states(pd, states);
2297         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2298                    states[0], states[1], states[2], states[3], states[4], states[5]);
2299
2300         return 0;
2301 }
2302
2303 static int pkt_seq_open(struct inode *inode, struct file *file)
2304 {
2305         return single_open(file, pkt_seq_show, PDE(inode)->data);
2306 }
2307
2308 static struct file_operations pkt_proc_fops = {
2309         .open   = pkt_seq_open,
2310         .read   = seq_read,
2311         .llseek = seq_lseek,
2312         .release = single_release
2313 };
2314
2315 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2316 {
2317         int i;
2318         int ret = 0;
2319         char b[BDEVNAME_SIZE];
2320         struct proc_dir_entry *proc;
2321         struct block_device *bdev;
2322
2323         if (pd->pkt_dev == dev) {
2324                 printk("pktcdvd: Recursive setup not allowed\n");
2325                 return -EBUSY;
2326         }
2327         for (i = 0; i < MAX_WRITERS; i++) {
2328                 struct pktcdvd_device *pd2 = pkt_devs[i];
2329                 if (!pd2)
2330                         continue;
2331                 if (pd2->bdev->bd_dev == dev) {
2332                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2333                         return -EBUSY;
2334                 }
2335                 if (pd2->pkt_dev == dev) {
2336                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2337                         return -EBUSY;
2338                 }
2339         }
2340
2341         bdev = bdget(dev);
2342         if (!bdev)
2343                 return -ENOMEM;
2344         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2345         if (ret)
2346                 return ret;
2347
2348         /* This is safe, since we have a reference from open(). */
2349         __module_get(THIS_MODULE);
2350
2351         if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2352                 printk("pktcdvd: not enough memory for buffers\n");
2353                 ret = -ENOMEM;
2354                 goto out_mem;
2355         }
2356
2357         pd->bdev = bdev;
2358         set_blocksize(bdev, CD_FRAMESIZE);
2359
2360         pkt_init_queue(pd);
2361
2362         atomic_set(&pd->cdrw.pending_bios, 0);
2363         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2364         if (IS_ERR(pd->cdrw.thread)) {
2365                 printk("pktcdvd: can't start kernel thread\n");
2366                 ret = -ENOMEM;
2367                 goto out_thread;
2368         }
2369
2370         proc = create_proc_entry(pd->name, 0, pkt_proc);
2371         if (proc) {
2372                 proc->data = pd;
2373                 proc->proc_fops = &pkt_proc_fops;
2374         }
2375         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2376         return 0;
2377
2378 out_thread:
2379         pkt_shrink_pktlist(pd);
2380 out_mem:
2381         blkdev_put(bdev);
2382         /* This is safe: open() is still holding a reference. */
2383         module_put(THIS_MODULE);
2384         return ret;
2385 }
2386
2387 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2388 {
2389         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2390
2391         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2392         BUG_ON(!pd);
2393
2394         switch (cmd) {
2395         /*
2396          * forward selected CDROM ioctls to CD-ROM, for UDF
2397          */
2398         case CDROMMULTISESSION:
2399         case CDROMREADTOCENTRY:
2400         case CDROM_LAST_WRITTEN:
2401         case CDROM_SEND_PACKET:
2402         case SCSI_IOCTL_SEND_COMMAND:
2403                 return ioctl_by_bdev(pd->bdev, cmd, arg);
2404
2405         case CDROMEJECT:
2406                 /*
2407                  * The door gets locked when the device is opened, so we
2408                  * have to unlock it or else the eject command fails.
2409                  */
2410                 pkt_lock_door(pd, 0);
2411                 return ioctl_by_bdev(pd->bdev, cmd, arg);
2412
2413         default:
2414                 printk("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2415                 return -ENOTTY;
2416         }
2417
2418         return 0;
2419 }
2420
2421 static int pkt_media_changed(struct gendisk *disk)
2422 {
2423         struct pktcdvd_device *pd = disk->private_data;
2424         struct gendisk *attached_disk;
2425
2426         if (!pd)
2427                 return 0;
2428         if (!pd->bdev)
2429                 return 0;
2430         attached_disk = pd->bdev->bd_disk;
2431         if (!attached_disk)
2432                 return 0;
2433         return attached_disk->fops->media_changed(attached_disk);
2434 }
2435
2436 static struct block_device_operations pktcdvd_ops = {
2437         .owner =                THIS_MODULE,
2438         .open =                 pkt_open,
2439         .release =              pkt_close,
2440         .ioctl =                pkt_ioctl,
2441         .media_changed =        pkt_media_changed,
2442 };
2443
2444 /*
2445  * Set up mapping from pktcdvd device to CD-ROM device.
2446  */
2447 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2448 {
2449         int idx;
2450         int ret = -ENOMEM;
2451         struct pktcdvd_device *pd;
2452         struct gendisk *disk;
2453         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2454
2455         for (idx = 0; idx < MAX_WRITERS; idx++)
2456                 if (!pkt_devs[idx])
2457                         break;
2458         if (idx == MAX_WRITERS) {
2459                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2460                 return -EBUSY;
2461         }
2462
2463         pd = kmalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2464         if (!pd)
2465                 return ret;
2466         memset(pd, 0, sizeof(struct pktcdvd_device));
2467
2468         pd->rb_pool = mempool_create(PKT_RB_POOL_SIZE, pkt_rb_alloc, pkt_rb_free, NULL);
2469         if (!pd->rb_pool)
2470                 goto out_mem;
2471
2472         disk = alloc_disk(1);
2473         if (!disk)
2474                 goto out_mem;
2475         pd->disk = disk;
2476
2477         spin_lock_init(&pd->lock);
2478         spin_lock_init(&pd->iosched.lock);
2479         sprintf(pd->name, "pktcdvd%d", idx);
2480         init_waitqueue_head(&pd->wqueue);
2481         pd->bio_queue = RB_ROOT;
2482
2483         disk->major = pkt_major;
2484         disk->first_minor = idx;
2485         disk->fops = &pktcdvd_ops;
2486         disk->flags = GENHD_FL_REMOVABLE;
2487         sprintf(disk->disk_name, "pktcdvd%d", idx);
2488         disk->private_data = pd;
2489         disk->queue = blk_alloc_queue(GFP_KERNEL);
2490         if (!disk->queue)
2491                 goto out_mem2;
2492
2493         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2494         ret = pkt_new_dev(pd, dev);
2495         if (ret)
2496                 goto out_new_dev;
2497
2498         add_disk(disk);
2499         pkt_devs[idx] = pd;
2500         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2501         return 0;
2502
2503 out_new_dev:
2504         blk_put_queue(disk->queue);
2505 out_mem2:
2506         put_disk(disk);
2507 out_mem:
2508         if (pd->rb_pool)
2509                 mempool_destroy(pd->rb_pool);
2510         kfree(pd);
2511         return ret;
2512 }
2513
2514 /*
2515  * Tear down mapping from pktcdvd device to CD-ROM device.
2516  */
2517 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2518 {
2519         struct pktcdvd_device *pd;
2520         int idx;
2521         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2522
2523         for (idx = 0; idx < MAX_WRITERS; idx++) {
2524                 pd = pkt_devs[idx];
2525                 if (pd && (pd->pkt_dev == pkt_dev))
2526                         break;
2527         }
2528         if (idx == MAX_WRITERS) {
2529                 DPRINTK("pktcdvd: dev not setup\n");
2530                 return -ENXIO;
2531         }
2532
2533         if (pd->refcnt > 0)
2534                 return -EBUSY;
2535
2536         if (!IS_ERR(pd->cdrw.thread))
2537                 kthread_stop(pd->cdrw.thread);
2538
2539         blkdev_put(pd->bdev);
2540
2541         pkt_shrink_pktlist(pd);
2542
2543         remove_proc_entry(pd->name, pkt_proc);
2544         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2545
2546         del_gendisk(pd->disk);
2547         blk_put_queue(pd->disk->queue);
2548         put_disk(pd->disk);
2549
2550         pkt_devs[idx] = NULL;
2551         mempool_destroy(pd->rb_pool);
2552         kfree(pd);
2553
2554         /* This is safe: open() is still holding a reference. */
2555         module_put(THIS_MODULE);
2556         return 0;
2557 }
2558
2559 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2560 {
2561         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2562         if (pd) {
2563                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2564                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2565         } else {
2566                 ctrl_cmd->dev = 0;
2567                 ctrl_cmd->pkt_dev = 0;
2568         }
2569         ctrl_cmd->num_devices = MAX_WRITERS;
2570 }
2571
2572 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2573 {
2574         void __user *argp = (void __user *)arg;
2575         struct pkt_ctrl_command ctrl_cmd;
2576         int ret = 0;
2577
2578         if (cmd != PACKET_CTRL_CMD)
2579                 return -ENOTTY;
2580
2581         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2582                 return -EFAULT;
2583
2584         switch (ctrl_cmd.command) {
2585         case PKT_CTRL_CMD_SETUP:
2586                 if (!capable(CAP_SYS_ADMIN))
2587                         return -EPERM;
2588                 down(&ctl_mutex);
2589                 ret = pkt_setup_dev(&ctrl_cmd);
2590                 up(&ctl_mutex);
2591                 break;
2592         case PKT_CTRL_CMD_TEARDOWN:
2593                 if (!capable(CAP_SYS_ADMIN))
2594                         return -EPERM;
2595                 down(&ctl_mutex);
2596                 ret = pkt_remove_dev(&ctrl_cmd);
2597                 up(&ctl_mutex);
2598                 break;
2599         case PKT_CTRL_CMD_STATUS:
2600                 down(&ctl_mutex);
2601                 pkt_get_status(&ctrl_cmd);
2602                 up(&ctl_mutex);
2603                 break;
2604         default:
2605                 return -ENOTTY;
2606         }
2607
2608         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2609                 return -EFAULT;
2610         return ret;
2611 }
2612
2613
2614 static struct file_operations pkt_ctl_fops = {
2615         .ioctl   = pkt_ctl_ioctl,
2616         .owner   = THIS_MODULE,
2617 };
2618
2619 static struct miscdevice pkt_misc = {
2620         .minor          = MISC_DYNAMIC_MINOR,
2621         .name           = "pktcdvd",
2622         .devfs_name     = "pktcdvd/control",
2623         .fops           = &pkt_ctl_fops
2624 };
2625
2626 static int pkt_init(void)
2627 {
2628         int ret;
2629
2630         psd_pool = mempool_create(PSD_POOL_SIZE, psd_pool_alloc, psd_pool_free, NULL);
2631         if (!psd_pool)
2632                 return -ENOMEM;
2633
2634         ret = register_blkdev(pkt_major, "pktcdvd");
2635         if (ret < 0) {
2636                 printk("pktcdvd: Unable to register block device\n");
2637                 goto out2;
2638         }
2639         if (!pkt_major)
2640                 pkt_major = ret;
2641
2642         ret = misc_register(&pkt_misc);
2643         if (ret) {
2644                 printk("pktcdvd: Unable to register misc device\n");
2645                 goto out;
2646         }
2647
2648         init_MUTEX(&ctl_mutex);
2649
2650         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2651
2652         DPRINTK("pktcdvd: %s\n", VERSION_CODE);
2653         return 0;
2654
2655 out:
2656         unregister_blkdev(pkt_major, "pktcdvd");
2657 out2:
2658         mempool_destroy(psd_pool);
2659         return ret;
2660 }
2661
2662 static void pkt_exit(void)
2663 {
2664         remove_proc_entry("pktcdvd", proc_root_driver);
2665         misc_deregister(&pkt_misc);
2666         unregister_blkdev(pkt_major, "pktcdvd");
2667         mempool_destroy(psd_pool);
2668 }
2669
2670 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2671 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2672 MODULE_LICENSE("GPL");
2673
2674 module_init(pkt_init);
2675 module_exit(pkt_exit);