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(unsigned int __nocast 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         rq->end_io = blk_end_sync_rq;
 379         elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
 380         generic_unplug_device(q);
 381         wait_for_completion(&wait);
 382
 383         if (rq->errors)
 384                 err = -EIO;
 385
 386         blk_put_request(rq);
 387         return err;
 388 }
 389
 390 /*
 391  * A generic sense dump / resolve mechanism should be implemented across
 392  * all ATAPI + SCSI devices.
 393  */
 394 static void pkt_dump_sense(struct packet_command *cgc)
 395 {
 396         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 397                                  "Medium error", "Hardware error", "Illegal request",
 398                                  "Unit attention", "Data protect", "Blank check" };
 399         int i;
 400         struct request_sense *sense = cgc->sense;
 401
 402         printk("pktcdvd:");
 403         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 404                 printk(" %02x", cgc->cmd[i]);
 405         printk(" - ");
 406
 407         if (sense == NULL) {
 408                 printk("no sense\n");
 409                 return;
 410         }
 411
 412         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 413
 414         if (sense->sense_key > 8) {
 415                 printk(" (INVALID)\n");
 416                 return;
 417         }
 418
 419         printk(" (%s)\n", info[sense->sense_key]);
 420 }
 421
 422 /*
 423  * flush the drive cache to media
 424  */
 425 static int pkt_flush_cache(struct pktcdvd_device *pd)
 426 {
 427         struct packet_command cgc;
 428
 429         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 430         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 431         cgc.quiet = 1;
 432
 433         /*
 434          * the IMMED bit -- we default to not setting it, although that
 435          * would allow a much faster close, this is safer
 436          */
 437 #if 0
 438         cgc.cmd[1] = 1 << 1;
 439 #endif
 440         return pkt_generic_packet(pd, &cgc);
 441 }
 442
 443 /*
 444  * speed is given as the normal factor, e.g. 4 for 4x
 445  */
 446 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
 447 {
 448         struct packet_command cgc;
 449         struct request_sense sense;
 450         int ret;
 451
 452         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 453         cgc.sense = &sense;
 454         cgc.cmd[0] = GPCMD_SET_SPEED;
 455         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 456         cgc.cmd[3] = read_speed & 0xff;
 457         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 458         cgc.cmd[5] = write_speed & 0xff;
 459
 460         if ((ret = pkt_generic_packet(pd, &cgc)))
 461                 pkt_dump_sense(&cgc);
 462
 463         return ret;
 464 }
 465
 466 /*
 467  * Queue a bio for processing by the low-level CD device. Must be called
 468  * from process context.
 469  */
 470 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio, int high_prio_read)
 471 {
 472         spin_lock(&pd->iosched.lock);
 473         if (bio_data_dir(bio) == READ) {
 474                 pkt_add_list_last(bio, &pd->iosched.read_queue,
 475                                   &pd->iosched.read_queue_tail);
 476                 if (high_prio_read)
 477                         pd->iosched.high_prio_read = 1;
 478         } else {
 479                 pkt_add_list_last(bio, &pd->iosched.write_queue,
 480                                   &pd->iosched.write_queue_tail);
 481         }
 482         spin_unlock(&pd->iosched.lock);
 483
 484         atomic_set(&pd->iosched.attention, 1);
 485         wake_up(&pd->wqueue);
 486 }
 487
 488 /*
 489  * Process the queued read/write requests. This function handles special
 490  * requirements for CDRW drives:
 491  * - A cache flush command must be inserted before a read request if the
 492  *   previous request was a write.
 493  * - Switching between reading and writing is slow, so don't it more often
 494  *   than necessary.
 495  * - Set the read speed according to current usage pattern. When only reading
 496  *   from the device, it's best to use the highest possible read speed, but
 497  *   when switching often between reading and writing, it's better to have the
 498  *   same read and write speeds.
 499  * - Reads originating from user space should have higher priority than reads
 500  *   originating from pkt_gather_data, because some process is usually waiting
 501  *   on reads of the first kind.
 502  */
 503 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 504 {
 505         request_queue_t *q;
 506
 507         if (atomic_read(&pd->iosched.attention) == 0)
 508                 return;
 509         atomic_set(&pd->iosched.attention, 0);
 510
 511         q = bdev_get_queue(pd->bdev);
 512
 513         for (;;) {
 514                 struct bio *bio;
 515                 int reads_queued, writes_queued, high_prio_read;
 516
 517                 spin_lock(&pd->iosched.lock);
 518                 reads_queued = (pd->iosched.read_queue != NULL);
 519                 writes_queued = (pd->iosched.write_queue != NULL);
 520                 if (!reads_queued)
 521                         pd->iosched.high_prio_read = 0;
 522                 high_prio_read = pd->iosched.high_prio_read;
 523                 spin_unlock(&pd->iosched.lock);
 524
 525                 if (!reads_queued && !writes_queued)
 526                         break;
 527
 528                 if (pd->iosched.writing) {
 529                         if (high_prio_read || (!writes_queued && reads_queued)) {
 530                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 531                                         VPRINTK("pktcdvd: write, waiting\n");
 532                                         break;
 533                                 }
 534                                 pkt_flush_cache(pd);
 535                                 pd->iosched.writing = 0;
 536                         }
 537                 } else {
 538                         if (!reads_queued && writes_queued) {
 539                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 540                                         VPRINTK("pktcdvd: read, waiting\n");
 541                                         break;
 542                                 }
 543                                 pd->iosched.writing = 1;
 544                         }
 545                 }
 546
 547                 spin_lock(&pd->iosched.lock);
 548                 if (pd->iosched.writing) {
 549                         bio = pkt_get_list_first(&pd->iosched.write_queue,
 550                                                  &pd->iosched.write_queue_tail);
 551                 } else {
 552                         bio = pkt_get_list_first(&pd->iosched.read_queue,
 553                                                  &pd->iosched.read_queue_tail);
 554                 }
 555                 spin_unlock(&pd->iosched.lock);
 556
 557                 if (!bio)
 558                         continue;
 559
 560                 if (bio_data_dir(bio) == READ)
 561                         pd->iosched.successive_reads += bio->bi_size >> 10;
 562                 else
 563                         pd->iosched.successive_reads = 0;
 564                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 565                         if (pd->read_speed == pd->write_speed) {
 566                                 pd->read_speed = MAX_SPEED;
 567                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 568                         }
 569                 } else {
 570                         if (pd->read_speed != pd->write_speed) {
 571                                 pd->read_speed = pd->write_speed;
 572                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 573                         }
 574                 }
 575
 576                 atomic_inc(&pd->cdrw.pending_bios);
 577                 generic_make_request(bio);
 578         }
 579 }
 580
 581 /*
 582  * Special care is needed if the underlying block device has a small
 583  * max_phys_segments value.
 584  */
 585 static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
 586 {
 587         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 588                 /*
 589                  * The cdrom device can handle one segment/frame
 590                  */
 591                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 592                 return 0;
 593         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
 594                 /*
 595                  * We can handle this case at the expense of some extra memory
 596                  * copies during write operations
 597                  */
 598                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 599                 return 0;
 600         } else {
 601                 printk("pktcdvd: cdrom max_phys_segments too small\n");
 602                 return -EIO;
 603         }
 604 }
 605
 606 /*
 607  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 608  */
 609 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 610 {
 611         unsigned int copy_size = CD_FRAMESIZE;
 612
 613         while (copy_size > 0) {
 614                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 615                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 616                         src_bvl->bv_offset + offs;
 617                 void *vto = page_address(dst_page) + dst_offs;
 618                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 619
 620                 BUG_ON(len < 0);
 621                 memcpy(vto, vfrom, len);
 622                 kunmap_atomic(vfrom, KM_USER0);
 623
 624                 seg++;
 625                 offs = 0;
 626                 dst_offs += len;
 627                 copy_size -= len;
 628         }
 629 }
 630
 631 /*
 632  * Copy all data for this packet to pkt->pages[], so that
 633  * a) The number of required segments for the write bio is minimized, which
 634  *    is necessary for some scsi controllers.
 635  * b) The data can be used as cache to avoid read requests if we receive a
 636  *    new write request for the same zone.
 637  */
 638 static void pkt_make_local_copy(struct packet_data *pkt, struct page **pages, int *offsets)
 639 {
 640         int f, p, offs;
 641
 642         /* Copy all data to pkt->pages[] */
 643         p = 0;
 644         offs = 0;
 645         for (f = 0; f < pkt->frames; f++) {
 646                 if (pages[f] != pkt->pages[p]) {
 647                         void *vfrom = kmap_atomic(pages[f], KM_USER0) + offsets[f];
 648                         void *vto = page_address(pkt->pages[p]) + offs;
 649                         memcpy(vto, vfrom, CD_FRAMESIZE);
 650                         kunmap_atomic(vfrom, KM_USER0);
 651                         pages[f] = pkt->pages[p];
 652                         offsets[f] = offs;
 653                 } else {
 654                         BUG_ON(offsets[f] != offs);
 655                 }
 656                 offs += CD_FRAMESIZE;
 657                 if (offs >= PAGE_SIZE) {
 658                         BUG_ON(offs > PAGE_SIZE);
 659                         offs = 0;
 660                         p++;
 661                 }
 662         }
 663 }
 664
 665 static int pkt_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
 666 {
 667         struct packet_data *pkt = bio->bi_private;
 668         struct pktcdvd_device *pd = pkt->pd;
 669         BUG_ON(!pd);
 670
 671         if (bio->bi_size)
 672                 return 1;
 673
 674         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 675                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 676
 677         if (err)
 678                 atomic_inc(&pkt->io_errors);
 679         if (atomic_dec_and_test(&pkt->io_wait)) {
 680                 atomic_inc(&pkt->run_sm);
 681                 wake_up(&pd->wqueue);
 682         }
 683         pkt_bio_finished(pd);
 684
 685         return 0;
 686 }
 687
 688 static int pkt_end_io_packet_write(struct bio *bio, unsigned int bytes_done, int err)
 689 {
 690         struct packet_data *pkt = bio->bi_private;
 691         struct pktcdvd_device *pd = pkt->pd;
 692         BUG_ON(!pd);
 693
 694         if (bio->bi_size)
 695                 return 1;
 696
 697         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
 698
 699         pd->stats.pkt_ended++;
 700
 701         pkt_bio_finished(pd);
 702         atomic_dec(&pkt->io_wait);
 703         atomic_inc(&pkt->run_sm);
 704         wake_up(&pd->wqueue);
 705         return 0;
 706 }
 707
 708 /*
 709  * Schedule reads for the holes in a packet
 710  */
 711 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 712 {
 713         int frames_read = 0;
 714         struct bio *bio;
 715         int f;
 716         char written[PACKET_MAX_SIZE];
 717
 718         BUG_ON(!pkt->orig_bios);
 719
 720         atomic_set(&pkt->io_wait, 0);
 721         atomic_set(&pkt->io_errors, 0);
 722
 723         if (pkt->cache_valid) {
 724                 VPRINTK("pkt_gather_data: zone %llx cached\n",
 725                         (unsigned long long)pkt->sector);
 726                 goto out_account;
 727         }
 728
 729         /*
 730          * Figure out which frames we need to read before we can write.
 731          */
 732         memset(written, 0, sizeof(written));
 733         spin_lock(&pkt->lock);
 734         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
 735                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
 736                 int num_frames = bio->bi_size / CD_FRAMESIZE;
 737                 BUG_ON(first_frame < 0);
 738                 BUG_ON(first_frame + num_frames > pkt->frames);
 739                 for (f = first_frame; f < first_frame + num_frames; f++)
 740                         written[f] = 1;
 741         }
 742         spin_unlock(&pkt->lock);
 743
 744         /*
 745          * Schedule reads for missing parts of the packet.
 746          */
 747         for (f = 0; f < pkt->frames; f++) {
 748                 int p, offset;
 749                 if (written[f])
 750                         continue;
 751                 bio = pkt->r_bios[f];
 752                 bio_init(bio);
 753                 bio->bi_max_vecs = 1;
 754                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 755                 bio->bi_bdev = pd->bdev;
 756                 bio->bi_end_io = pkt_end_io_read;
 757                 bio->bi_private = pkt;
 758
 759                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
 760                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 761                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
 762                         f, pkt->pages[p], offset);
 763                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
 764                         BUG();
 765
 766                 atomic_inc(&pkt->io_wait);
 767                 bio->bi_rw = READ;
 768                 pkt_queue_bio(pd, bio, 0);
 769                 frames_read++;
 770         }
 771
 772 out_account:
 773         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
 774                 frames_read, (unsigned long long)pkt->sector);
 775         pd->stats.pkt_started++;
 776         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
 777         pd->stats.secs_w += pd->settings.size;
 778 }
 779
 780 /*
 781  * Find a packet matching zone, or the least recently used packet if
 782  * there is no match.
 783  */
 784 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
 785 {
 786         struct packet_data *pkt;
 787
 788         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
 789                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
 790                         list_del_init(&pkt->list);
 791                         if (pkt->sector != zone)
 792                                 pkt->cache_valid = 0;
 793                         break;
 794                 }
 795         }
 796         return pkt;
 797 }
 798
 799 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 800 {
 801         if (pkt->cache_valid) {
 802                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 803         } else {
 804                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
 805         }
 806 }
 807
 808 /*
 809  * recover a failed write, query for relocation if possible
 810  *
 811  * returns 1 if recovery is possible, or 0 if not
 812  *
 813  */
 814 static int pkt_start_recovery(struct packet_data *pkt)
 815 {
 816         /*
 817          * FIXME. We need help from the file system to implement
 818          * recovery handling.
 819          */
 820         return 0;
 821 #if 0
 822         struct request *rq = pkt->rq;
 823         struct pktcdvd_device *pd = rq->rq_disk->private_data;
 824         struct block_device *pkt_bdev;
 825         struct super_block *sb = NULL;
 826         unsigned long old_block, new_block;
 827         sector_t new_sector;
 828
 829         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
 830         if (pkt_bdev) {
 831                 sb = get_super(pkt_bdev);
 832                 bdput(pkt_bdev);
 833         }
 834
 835         if (!sb)
 836                 return 0;
 837
 838         if (!sb->s_op || !sb->s_op->relocate_blocks)
 839                 goto out;
 840
 841         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
 842         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
 843                 goto out;
 844
 845         new_sector = new_block * (CD_FRAMESIZE >> 9);
 846         pkt->sector = new_sector;
 847
 848         pkt->bio->bi_sector = new_sector;
 849         pkt->bio->bi_next = NULL;
 850         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
 851         pkt->bio->bi_idx = 0;
 852
 853         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
 854         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
 855         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
 856         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
 857         BUG_ON(pkt->bio->bi_private != pkt);
 858
 859         drop_super(sb);
 860         return 1;
 861
 862 out:
 863         drop_super(sb);
 864         return 0;
 865 #endif
 866 }
 867
 868 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
 869 {
 870 #if PACKET_DEBUG > 1
 871         static const char *state_name[] = {
 872                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
 873         };
 874         enum packet_data_state old_state = pkt->state;
 875         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
 876                 state_name[old_state], state_name[state]);
 877 #endif
 878         pkt->state = state;
 879 }
 880
 881 /*
 882  * Scan the work queue to see if we can start a new packet.
 883  * returns non-zero if any work was done.
 884  */
 885 static int pkt_handle_queue(struct pktcdvd_device *pd)
 886 {
 887         struct packet_data *pkt, *p;
 888         struct bio *bio = NULL;
 889         sector_t zone = 0; /* Suppress gcc warning */
 890         struct pkt_rb_node *node, *first_node;
 891         struct rb_node *n;
 892
 893         VPRINTK("handle_queue\n");
 894
 895         atomic_set(&pd->scan_queue, 0);
 896
 897         if (list_empty(&pd->cdrw.pkt_free_list)) {
 898                 VPRINTK("handle_queue: no pkt\n");
 899                 return 0;
 900         }
 901
 902         /*
 903          * Try to find a zone we are not already working on.
 904          */
 905         spin_lock(&pd->lock);
 906         first_node = pkt_rbtree_find(pd, pd->current_sector);
 907         if (!first_node) {
 908                 n = rb_first(&pd->bio_queue);
 909                 if (n)
 910                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
 911         }
 912         node = first_node;
 913         while (node) {
 914                 bio = node->bio;
 915                 zone = ZONE(bio->bi_sector, pd);
 916                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
 917                         if (p->sector == zone)
 918                                 goto try_next_bio;
 919                 }
 920                 break;
 921 try_next_bio:
 922                 node = pkt_rbtree_next(node);
 923                 if (!node) {
 924                         n = rb_first(&pd->bio_queue);
 925                         if (n)
 926                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
 927                 }
 928                 if (node == first_node)
 929                         node = NULL;
 930         }
 931         spin_unlock(&pd->lock);
 932         if (!bio) {
 933                 VPRINTK("handle_queue: no bio\n");
 934                 return 0;
 935         }
 936
 937         pkt = pkt_get_packet_data(pd, zone);
 938         BUG_ON(!pkt);
 939
 940         pd->current_sector = zone + pd->settings.size;
 941         pkt->sector = zone;
 942         pkt->frames = pd->settings.size >> 2;
 943         BUG_ON(pkt->frames > PACKET_MAX_SIZE);
 944         pkt->write_size = 0;
 945
 946         /*
 947          * Scan work queue for bios in the same zone and link them
 948          * to this packet.
 949          */
 950         spin_lock(&pd->lock);
 951         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
 952         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
 953                 bio = node->bio;
 954                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
 955                         (unsigned long long)ZONE(bio->bi_sector, pd));
 956                 if (ZONE(bio->bi_sector, pd) != zone)
 957                         break;
 958                 pkt_rbtree_erase(pd, node);
 959                 spin_lock(&pkt->lock);
 960                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
 961                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
 962                 spin_unlock(&pkt->lock);
 963         }
 964         spin_unlock(&pd->lock);
 965
 966         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
 967         pkt_set_state(pkt, PACKET_WAITING_STATE);
 968         atomic_set(&pkt->run_sm, 1);
 969
 970         spin_lock(&pd->cdrw.active_list_lock);
 971         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
 972         spin_unlock(&pd->cdrw.active_list_lock);
 973
 974         return 1;
 975 }
 976
 977 /*
 978  * Assemble a bio to write one packet and queue the bio for processing
 979  * by the underlying block device.
 980  */
 981 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 982 {
 983         struct bio *bio;
 984         struct page *pages[PACKET_MAX_SIZE];
 985         int offsets[PACKET_MAX_SIZE];
 986         int f;
 987         int frames_write;
 988
 989         for (f = 0; f < pkt->frames; f++) {
 990                 pages[f] = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
 991                 offsets[f] = (f * CD_FRAMESIZE) % PAGE_SIZE;
 992         }
 993
 994         /*
 995          * Fill-in pages[] and offsets[] with data from orig_bios.
 996          */
 997         frames_write = 0;
 998         spin_lock(&pkt->lock);
 999         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1000                 int segment = bio->bi_idx;
1001                 int src_offs = 0;
1002                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1003                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1004                 BUG_ON(first_frame < 0);
1005                 BUG_ON(first_frame + num_frames > pkt->frames);
1006                 for (f = first_frame; f < first_frame + num_frames; f++) {
1007                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1008
1009                         while (src_offs >= src_bvl->bv_len) {
1010                                 src_offs -= src_bvl->bv_len;
1011                                 segment++;
1012                                 BUG_ON(segment >= bio->bi_vcnt);
1013                                 src_bvl = bio_iovec_idx(bio, segment);
1014                         }
1015
1016                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1017                                 pages[f] = src_bvl->bv_page;
1018                                 offsets[f] = src_bvl->bv_offset + src_offs;
1019                         } else {
1020                                 pkt_copy_bio_data(bio, segment, src_offs,
1021                                                   pages[f], offsets[f]);
1022                         }
1023                         src_offs += CD_FRAMESIZE;
1024                         frames_write++;
1025                 }
1026         }
1027         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1028         spin_unlock(&pkt->lock);
1029
1030         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1031                 frames_write, (unsigned long long)pkt->sector);
1032         BUG_ON(frames_write != pkt->write_size);
1033
1034         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1035                 pkt_make_local_copy(pkt, pages, offsets);
1036                 pkt->cache_valid = 1;
1037         } else {
1038                 pkt->cache_valid = 0;
1039         }
1040
1041         /* Start the write request */
1042         bio_init(pkt->w_bio);
1043         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1044         pkt->w_bio->bi_sector = pkt->sector;
1045         pkt->w_bio->bi_bdev = pd->bdev;
1046         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1047         pkt->w_bio->bi_private = pkt;
1048         for (f = 0; f < pkt->frames; f++) {
1049                 if ((f + 1 < pkt->frames) && (pages[f + 1] == pages[f]) &&
1050                     (offsets[f + 1] = offsets[f] + CD_FRAMESIZE)) {
1051                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE * 2, offsets[f]))
1052                                 BUG();
1053                         f++;
1054                 } else {
1055                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE, offsets[f]))
1056                                 BUG();
1057                 }
1058         }
1059         VPRINTK("pktcdvd: vcnt=%d\n", pkt->w_bio->bi_vcnt);
1060
1061         atomic_set(&pkt->io_wait, 1);
1062         pkt->w_bio->bi_rw = WRITE;
1063         pkt_queue_bio(pd, pkt->w_bio, 0);
1064 }
1065
1066 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1067 {
1068         struct bio *bio, *next;
1069
1070         if (!uptodate)
1071                 pkt->cache_valid = 0;
1072
1073         /* Finish all bios corresponding to this packet */
1074         bio = pkt->orig_bios;
1075         while (bio) {
1076                 next = bio->bi_next;
1077                 bio->bi_next = NULL;
1078                 bio_endio(bio, bio->bi_size, uptodate ? 0 : -EIO);
1079                 bio = next;
1080         }
1081         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1082 }
1083
1084 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1085 {
1086         int uptodate;
1087
1088         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1089
1090         for (;;) {
1091                 switch (pkt->state) {
1092                 case PACKET_WAITING_STATE:
1093                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1094                                 return;
1095
1096                         pkt->sleep_time = 0;
1097                         pkt_gather_data(pd, pkt);
1098                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1099                         break;
1100
1101                 case PACKET_READ_WAIT_STATE:
1102                         if (atomic_read(&pkt->io_wait) > 0)
1103                                 return;
1104
1105                         if (atomic_read(&pkt->io_errors) > 0) {
1106                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1107                         } else {
1108                                 pkt_start_write(pd, pkt);
1109                         }
1110                         break;
1111
1112                 case PACKET_WRITE_WAIT_STATE:
1113                         if (atomic_read(&pkt->io_wait) > 0)
1114                                 return;
1115
1116                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1117                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1118                         } else {
1119                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1120                         }
1121                         break;
1122
1123                 case PACKET_RECOVERY_STATE:
1124                         if (pkt_start_recovery(pkt)) {
1125                                 pkt_start_write(pd, pkt);
1126                         } else {
1127                                 VPRINTK("No recovery possible\n");
1128                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1129                         }
1130                         break;
1131
1132                 case PACKET_FINISHED_STATE:
1133                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1134                         pkt_finish_packet(pkt, uptodate);
1135                         return;
1136
1137                 default:
1138                         BUG();
1139                         break;
1140                 }
1141         }
1142 }
1143
1144 static void pkt_handle_packets(struct pktcdvd_device *pd)
1145 {
1146         struct packet_data *pkt, *next;
1147
1148         VPRINTK("pkt_handle_packets\n");
1149
1150         /*
1151          * Run state machine for active packets
1152          */
1153         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1154                 if (atomic_read(&pkt->run_sm) > 0) {
1155                         atomic_set(&pkt->run_sm, 0);
1156                         pkt_run_state_machine(pd, pkt);
1157                 }
1158         }
1159
1160         /*
1161          * Move no longer active packets to the free list
1162          */
1163         spin_lock(&pd->cdrw.active_list_lock);
1164         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1165                 if (pkt->state == PACKET_FINISHED_STATE) {
1166                         list_del(&pkt->list);
1167                         pkt_put_packet_data(pd, pkt);
1168                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1169                         atomic_set(&pd->scan_queue, 1);
1170                 }
1171         }
1172         spin_unlock(&pd->cdrw.active_list_lock);
1173 }
1174
1175 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1176 {
1177         struct packet_data *pkt;
1178         int i;
1179
1180         for (i = 0; i <= PACKET_NUM_STATES; i++)
1181                 states[i] = 0;
1182
1183         spin_lock(&pd->cdrw.active_list_lock);
1184         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1185                 states[pkt->state]++;
1186         }
1187         spin_unlock(&pd->cdrw.active_list_lock);
1188 }
1189
1190 /*
1191  * kcdrwd is woken up when writes have been queued for one of our
1192  * registered devices
1193  */
1194 static int kcdrwd(void *foobar)
1195 {
1196         struct pktcdvd_device *pd = foobar;
1197         struct packet_data *pkt;
1198         long min_sleep_time, residue;
1199
1200         set_user_nice(current, -20);
1201
1202         for (;;) {
1203                 DECLARE_WAITQUEUE(wait, current);
1204
1205                 /*
1206                  * Wait until there is something to do
1207                  */
1208                 add_wait_queue(&pd->wqueue, &wait);
1209                 for (;;) {
1210                         set_current_state(TASK_INTERRUPTIBLE);
1211
1212                         /* Check if we need to run pkt_handle_queue */
1213                         if (atomic_read(&pd->scan_queue) > 0)
1214                                 goto work_to_do;
1215
1216                         /* Check if we need to run the state machine for some packet */
1217                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1218                                 if (atomic_read(&pkt->run_sm) > 0)
1219                                         goto work_to_do;
1220                         }
1221
1222                         /* Check if we need to process the iosched queues */
1223                         if (atomic_read(&pd->iosched.attention) != 0)
1224                                 goto work_to_do;
1225
1226                         /* Otherwise, go to sleep */
1227                         if (PACKET_DEBUG > 1) {
1228                                 int states[PACKET_NUM_STATES];
1229                                 pkt_count_states(pd, states);
1230                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1231                                         states[0], states[1], states[2], states[3],
1232                                         states[4], states[5]);
1233                         }
1234
1235                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1236                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1237                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1238                                         min_sleep_time = pkt->sleep_time;
1239                         }
1240
1241                         generic_unplug_device(bdev_get_queue(pd->bdev));
1242
1243                         VPRINTK("kcdrwd: sleeping\n");
1244                         residue = schedule_timeout(min_sleep_time);
1245                         VPRINTK("kcdrwd: wake up\n");
1246
1247                         /* make swsusp happy with our thread */
1248                         if (current->flags & PF_FREEZE)
1249                                 refrigerator(PF_FREEZE);
1250
1251                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1252                                 if (!pkt->sleep_time)
1253                                         continue;
1254                                 pkt->sleep_time -= min_sleep_time - residue;
1255                                 if (pkt->sleep_time <= 0) {
1256                                         pkt->sleep_time = 0;
1257                                         atomic_inc(&pkt->run_sm);
1258                                 }
1259                         }
1260
1261                         if (signal_pending(current)) {
1262                                 flush_signals(current);
1263                         }
1264                         if (kthread_should_stop())
1265                                 break;
1266                 }
1267 work_to_do:
1268                 set_current_state(TASK_RUNNING);
1269                 remove_wait_queue(&pd->wqueue, &wait);
1270
1271                 if (kthread_should_stop())
1272                         break;
1273
1274                 /*
1275                  * if pkt_handle_queue returns true, we can queue
1276                  * another request.
1277                  */
1278                 while (pkt_handle_queue(pd))
1279                         ;
1280
1281                 /*
1282                  * Handle packet state machine
1283                  */
1284                 pkt_handle_packets(pd);
1285
1286                 /*
1287                  * Handle iosched queues
1288                  */
1289                 pkt_iosched_process_queue(pd);
1290         }
1291
1292         return 0;
1293 }
1294
1295 static void pkt_print_settings(struct pktcdvd_device *pd)
1296 {
1297         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1298         printk("%u blocks, ", pd->settings.size >> 2);
1299         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1300 }
1301
1302 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1303 {
1304         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1305
1306         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1307         cgc->cmd[2] = page_code | (page_control << 6);
1308         cgc->cmd[7] = cgc->buflen >> 8;
1309         cgc->cmd[8] = cgc->buflen & 0xff;
1310         cgc->data_direction = CGC_DATA_READ;
1311         return pkt_generic_packet(pd, cgc);
1312 }
1313
1314 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1315 {
1316         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1317         memset(cgc->buffer, 0, 2);
1318         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1319         cgc->cmd[1] = 0x10;             /* PF */
1320         cgc->cmd[7] = cgc->buflen >> 8;
1321         cgc->cmd[8] = cgc->buflen & 0xff;
1322         cgc->data_direction = CGC_DATA_WRITE;
1323         return pkt_generic_packet(pd, cgc);
1324 }
1325
1326 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1327 {
1328         struct packet_command cgc;
1329         int ret;
1330
1331         /* set up command and get the disc info */
1332         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1333         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1334         cgc.cmd[8] = cgc.buflen = 2;
1335         cgc.quiet = 1;
1336
1337         if ((ret = pkt_generic_packet(pd, &cgc)))
1338                 return ret;
1339
1340         /* not all drives have the same disc_info length, so requeue
1341          * packet with the length the drive tells us it can supply
1342          */
1343         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1344                      sizeof(di->disc_information_length);
1345
1346         if (cgc.buflen > sizeof(disc_information))
1347                 cgc.buflen = sizeof(disc_information);
1348
1349         cgc.cmd[8] = cgc.buflen;
1350         return pkt_generic_packet(pd, &cgc);
1351 }
1352
1353 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1354 {
1355         struct packet_command cgc;
1356         int ret;
1357
1358         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1359         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1360         cgc.cmd[1] = type & 3;
1361         cgc.cmd[4] = (track & 0xff00) >> 8;
1362         cgc.cmd[5] = track & 0xff;
1363         cgc.cmd[8] = 8;
1364         cgc.quiet = 1;
1365
1366         if ((ret = pkt_generic_packet(pd, &cgc)))
1367                 return ret;
1368
1369         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1370                      sizeof(ti->track_information_length);
1371
1372         if (cgc.buflen > sizeof(track_information))
1373                 cgc.buflen = sizeof(track_information);
1374
1375         cgc.cmd[8] = cgc.buflen;
1376         return pkt_generic_packet(pd, &cgc);
1377 }
1378
1379 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1380 {
1381         disc_information di;
1382         track_information ti;
1383         __u32 last_track;
1384         int ret = -1;
1385
1386         if ((ret = pkt_get_disc_info(pd, &di)))
1387                 return ret;
1388
1389         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1390         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1391                 return ret;
1392
1393         /* if this track is blank, try the previous. */
1394         if (ti.blank) {
1395                 last_track--;
1396                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1397                         return ret;
1398         }
1399
1400         /* if last recorded field is valid, return it. */
1401         if (ti.lra_v) {
1402                 *last_written = be32_to_cpu(ti.last_rec_address);
1403         } else {
1404                 /* make it up instead */
1405                 *last_written = be32_to_cpu(ti.track_start) +
1406                                 be32_to_cpu(ti.track_size);
1407                 if (ti.free_blocks)
1408                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1409         }
1410         return 0;
1411 }
1412
1413 /*
1414  * write mode select package based on pd->settings
1415  */
1416 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1417 {
1418         struct packet_command cgc;
1419         struct request_sense sense;
1420         write_param_page *wp;
1421         char buffer[128];
1422         int ret, size;
1423
1424         /* doesn't apply to DVD+RW or DVD-RAM */
1425         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1426                 return 0;
1427
1428         memset(buffer, 0, sizeof(buffer));
1429         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1430         cgc.sense = &sense;
1431         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1432                 pkt_dump_sense(&cgc);
1433                 return ret;
1434         }
1435
1436         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1437         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1438         if (size > sizeof(buffer))
1439                 size = sizeof(buffer);
1440
1441         /*
1442          * now get it all
1443          */
1444         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1445         cgc.sense = &sense;
1446         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1447                 pkt_dump_sense(&cgc);
1448                 return ret;
1449         }
1450
1451         /*
1452          * write page is offset header + block descriptor length
1453          */
1454         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1455
1456         wp->fp = pd->settings.fp;
1457         wp->track_mode = pd->settings.track_mode;
1458         wp->write_type = pd->settings.write_type;
1459         wp->data_block_type = pd->settings.block_mode;
1460
1461         wp->multi_session = 0;
1462
1463 #ifdef PACKET_USE_LS
1464         wp->link_size = 7;
1465         wp->ls_v = 1;
1466 #endif
1467
1468         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1469                 wp->session_format = 0;
1470                 wp->subhdr2 = 0x20;
1471         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1472                 wp->session_format = 0x20;
1473                 wp->subhdr2 = 8;
1474 #if 0
1475                 wp->mcn[0] = 0x80;
1476                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1477 #endif
1478         } else {
1479                 /*
1480                  * paranoia
1481                  */
1482                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1483                 return 1;
1484         }
1485         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1486
1487         cgc.buflen = cgc.cmd[8] = size;
1488         if ((ret = pkt_mode_select(pd, &cgc))) {
1489                 pkt_dump_sense(&cgc);
1490                 return ret;
1491         }
1492
1493         pkt_print_settings(pd);
1494         return 0;
1495 }
1496
1497 /*
1498  * 0 -- we can write to this track, 1 -- we can't
1499  */
1500 static int pkt_good_track(track_information *ti)
1501 {
1502         /*
1503          * only good for CD-RW at the moment, not DVD-RW
1504          */
1505
1506         /*
1507          * FIXME: only for FP
1508          */
1509         if (ti->fp == 0)
1510                 return 0;
1511
1512         /*
1513          * "good" settings as per Mt Fuji.
1514          */
1515         if (ti->rt == 0 && ti->blank == 0 && ti->packet == 1)
1516                 return 0;
1517
1518         if (ti->rt == 0 && ti->blank == 1 && ti->packet == 1)
1519                 return 0;
1520
1521         if (ti->rt == 1 && ti->blank == 0 && ti->packet == 1)
1522                 return 0;
1523
1524         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1525         return 1;
1526 }
1527
1528 /*
1529  * 0 -- we can write to this disc, 1 -- we can't
1530  */
1531 static int pkt_good_disc(struct pktcdvd_device *pd, disc_information *di)
1532 {
1533         switch (pd->mmc3_profile) {
1534                 case 0x0a: /* CD-RW */
1535                 case 0xffff: /* MMC3 not supported */
1536                         break;
1537                 case 0x1a: /* DVD+RW */
1538                 case 0x13: /* DVD-RW */
1539                 case 0x12: /* DVD-RAM */
1540                         return 0;
1541                 default:
1542                         printk("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1543                         return 1;
1544         }
1545
1546         /*
1547          * for disc type 0xff we should probably reserve a new track.
1548          * but i'm not sure, should we leave this to user apps? probably.
1549          */
1550         if (di->disc_type == 0xff) {
1551                 printk("pktcdvd: Unknown disc. No track?\n");
1552                 return 1;
1553         }
1554
1555         if (di->disc_type != 0x20 && di->disc_type != 0) {
1556                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1557                 return 1;
1558         }
1559
1560         if (di->erasable == 0) {
1561                 printk("pktcdvd: Disc not erasable\n");
1562                 return 1;
1563         }
1564
1565         if (di->border_status == PACKET_SESSION_RESERVED) {
1566                 printk("pktcdvd: Can't write to last track (reserved)\n");
1567                 return 1;
1568         }
1569
1570         return 0;
1571 }
1572
1573 static int pkt_probe_settings(struct pktcdvd_device *pd)
1574 {
1575         struct packet_command cgc;
1576         unsigned char buf[12];
1577         disc_information di;
1578         track_information ti;
1579         int ret, track;
1580
1581         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1582         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1583         cgc.cmd[8] = 8;
1584         ret = pkt_generic_packet(pd, &cgc);
1585         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1586
1587         memset(&di, 0, sizeof(disc_information));
1588         memset(&ti, 0, sizeof(track_information));
1589
1590         if ((ret = pkt_get_disc_info(pd, &di))) {
1591                 printk("failed get_disc\n");
1592                 return ret;
1593         }
1594
1595         if (pkt_good_disc(pd, &di))
1596                 return -ENXIO;
1597
1598         switch (pd->mmc3_profile) {
1599                 case 0x1a: /* DVD+RW */
1600                         printk("pktcdvd: inserted media is DVD+RW\n");
1601                         break;
1602                 case 0x13: /* DVD-RW */
1603                         printk("pktcdvd: inserted media is DVD-RW\n");
1604                         break;
1605                 case 0x12: /* DVD-RAM */
1606                         printk("pktcdvd: inserted media is DVD-RAM\n");
1607                         break;
1608                 default:
1609                         printk("pktcdvd: inserted media is CD-R%s\n", di.erasable ? "W" : "");
1610                         break;
1611         }
1612         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1613
1614         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1615         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1616                 printk("pktcdvd: failed get_track\n");
1617                 return ret;
1618         }
1619
1620         if (pkt_good_track(&ti)) {
1621                 printk("pktcdvd: can't write to this track\n");
1622                 return -ENXIO;
1623         }
1624
1625         /*
1626          * we keep packet size in 512 byte units, makes it easier to
1627          * deal with request calculations.
1628          */
1629         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1630         if (pd->settings.size == 0) {
1631                 printk("pktcdvd: detected zero packet size!\n");
1632                 pd->settings.size = 128;
1633         }
1634         pd->settings.fp = ti.fp;
1635         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1636
1637         if (ti.nwa_v) {
1638                 pd->nwa = be32_to_cpu(ti.next_writable);
1639                 set_bit(PACKET_NWA_VALID, &pd->flags);
1640         }
1641
1642         /*
1643          * in theory we could use lra on -RW media as well and just zero
1644          * blocks that haven't been written yet, but in practice that
1645          * is just a no-go. we'll use that for -R, naturally.
1646          */
1647         if (ti.lra_v) {
1648                 pd->lra = be32_to_cpu(ti.last_rec_address);
1649                 set_bit(PACKET_LRA_VALID, &pd->flags);
1650         } else {
1651                 pd->lra = 0xffffffff;
1652                 set_bit(PACKET_LRA_VALID, &pd->flags);
1653         }
1654
1655         /*
1656          * fine for now
1657          */
1658         pd->settings.link_loss = 7;
1659         pd->settings.write_type = 0;    /* packet */
1660         pd->settings.track_mode = ti.track_mode;
1661
1662         /*
1663          * mode1 or mode2 disc
1664          */
1665         switch (ti.data_mode) {
1666                 case PACKET_MODE1:
1667                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1668                         break;
1669                 case PACKET_MODE2:
1670                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1671                         break;
1672                 default:
1673                         printk("pktcdvd: unknown data mode\n");
1674                         return 1;
1675         }
1676         return 0;
1677 }
1678
1679 /*
1680  * enable/disable write caching on drive
1681  */
1682 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1683 {
1684         struct packet_command cgc;
1685         struct request_sense sense;
1686         unsigned char buf[64];
1687         int ret;
1688
1689         memset(buf, 0, sizeof(buf));
1690         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1691         cgc.sense = &sense;
1692         cgc.buflen = pd->mode_offset + 12;
1693
1694         /*
1695          * caching mode page might not be there, so quiet this command
1696          */
1697         cgc.quiet = 1;
1698
1699         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1700                 return ret;
1701
1702         buf[pd->mode_offset + 10] |= (!!set << 2);
1703
1704         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1705         ret = pkt_mode_select(pd, &cgc);
1706         if (ret) {
1707                 printk("pktcdvd: write caching control failed\n");
1708                 pkt_dump_sense(&cgc);
1709         } else if (!ret && set)
1710                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1711         return ret;
1712 }
1713
1714 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1715 {
1716         struct packet_command cgc;
1717
1718         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1719         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1720         cgc.cmd[4] = lockflag ? 1 : 0;
1721         return pkt_generic_packet(pd, &cgc);
1722 }
1723
1724 /*
1725  * Returns drive maximum write speed
1726  */
1727 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1728 {
1729         struct packet_command cgc;
1730         struct request_sense sense;
1731         unsigned char buf[256+18];
1732         unsigned char *cap_buf;
1733         int ret, offset;
1734
1735         memset(buf, 0, sizeof(buf));
1736         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1737         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1738         cgc.sense = &sense;
1739
1740         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1741         if (ret) {
1742                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1743                              sizeof(struct mode_page_header);
1744                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1745                 if (ret) {
1746                         pkt_dump_sense(&cgc);
1747                         return ret;
1748                 }
1749         }
1750
1751         offset = 20;                        /* Obsoleted field, used by older drives */
1752         if (cap_buf[1] >= 28)
1753                 offset = 28;                /* Current write speed selected */
1754         if (cap_buf[1] >= 30) {
1755                 /* If the drive reports at least one "Logical Unit Write
1756                  * Speed Performance Descriptor Block", use the information
1757                  * in the first block. (contains the highest speed)
1758                  */
1759                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1760                 if (num_spdb > 0)
1761                         offset = 34;
1762         }
1763
1764         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1765         return 0;
1766 }
1767
1768 /* These tables from cdrecord - I don't have orange book */
1769 /* standard speed CD-RW (1-4x) */
1770 static char 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, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1773 };
1774 /* high speed CD-RW (-10x) */
1775 static char hs_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, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1778 };
1779 /* ultra high speed CD-RW */
1780 static char us_clv_to_speed[16] = {
1781         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1782            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1783 };
1784
1785 /*
1786  * reads the maximum media speed from ATIP
1787  */
1788 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1789 {
1790         struct packet_command cgc;
1791         struct request_sense sense;
1792         unsigned char buf[64];
1793         unsigned int size, st, sp;
1794         int ret;
1795
1796         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1797         cgc.sense = &sense;
1798         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1799         cgc.cmd[1] = 2;
1800         cgc.cmd[2] = 4; /* READ ATIP */
1801         cgc.cmd[8] = 2;
1802         ret = pkt_generic_packet(pd, &cgc);
1803         if (ret) {
1804                 pkt_dump_sense(&cgc);
1805                 return ret;
1806         }
1807         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1808         if (size > sizeof(buf))
1809                 size = sizeof(buf);
1810
1811         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1812         cgc.sense = &sense;
1813         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1814         cgc.cmd[1] = 2;
1815         cgc.cmd[2] = 4;
1816         cgc.cmd[8] = size;
1817         ret = pkt_generic_packet(pd, &cgc);
1818         if (ret) {
1819                 pkt_dump_sense(&cgc);
1820                 return ret;
1821         }
1822
1823         if (!buf[6] & 0x40) {
1824                 printk("pktcdvd: Disc type is not CD-RW\n");
1825                 return 1;
1826         }
1827         if (!buf[6] & 0x4) {
1828                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1829                 return 1;
1830         }
1831
1832         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1833
1834         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1835
1836         /* Info from cdrecord */
1837         switch (st) {
1838                 case 0: /* standard speed */
1839                         *speed = clv_to_speed[sp];
1840                         break;
1841                 case 1: /* high speed */
1842                         *speed = hs_clv_to_speed[sp];
1843                         break;
1844                 case 2: /* ultra high speed */
1845                         *speed = us_clv_to_speed[sp];
1846                         break;
1847                 default:
1848                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1849                         return 1;
1850         }
1851         if (*speed) {
1852                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1853                 return 0;
1854         } else {
1855                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1856                 return 1;
1857         }
1858 }
1859
1860 static int pkt_perform_opc(struct pktcdvd_device *pd)
1861 {
1862         struct packet_command cgc;
1863         struct request_sense sense;
1864         int ret;
1865
1866         VPRINTK("pktcdvd: Performing OPC\n");
1867
1868         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1869         cgc.sense = &sense;
1870         cgc.timeout = 60*HZ;
1871         cgc.cmd[0] = GPCMD_SEND_OPC;
1872         cgc.cmd[1] = 1;
1873         if ((ret = pkt_generic_packet(pd, &cgc)))
1874                 pkt_dump_sense(&cgc);
1875         return ret;
1876 }
1877
1878 static int pkt_open_write(struct pktcdvd_device *pd)
1879 {
1880         int ret;
1881         unsigned int write_speed, media_write_speed, read_speed;
1882
1883         if ((ret = pkt_probe_settings(pd))) {
1884                 DPRINTK("pktcdvd: %s failed probe\n", pd->name);
1885                 return -EIO;
1886         }
1887
1888         if ((ret = pkt_set_write_settings(pd))) {
1889                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1890                 return -EIO;
1891         }
1892
1893         pkt_write_caching(pd, USE_WCACHING);
1894
1895         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1896                 write_speed = 16 * 177;
1897         switch (pd->mmc3_profile) {
1898                 case 0x13: /* DVD-RW */
1899                 case 0x1a: /* DVD+RW */
1900                 case 0x12: /* DVD-RAM */
1901                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1902                         break;
1903                 default:
1904                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1905                                 media_write_speed = 16;
1906                         write_speed = min(write_speed, media_write_speed * 177);
1907                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1908                         break;
1909         }
1910         read_speed = write_speed;
1911
1912         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1913                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1914                 return -EIO;
1915         }
1916         pd->write_speed = write_speed;
1917         pd->read_speed = read_speed;
1918
1919         if ((ret = pkt_perform_opc(pd))) {
1920                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1921         }
1922
1923         return 0;
1924 }
1925
1926 /*
1927  * called at open time.
1928  */
1929 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1930 {
1931         int ret;
1932         long lba;
1933         request_queue_t *q;
1934
1935         /*
1936          * We need to re-open the cdrom device without O_NONBLOCK to be able
1937          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1938          * so bdget() can't fail.
1939          */
1940         bdget(pd->bdev->bd_dev);
1941         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1942                 goto out;
1943
1944         if ((ret = pkt_get_last_written(pd, &lba))) {
1945                 printk("pktcdvd: pkt_get_last_written failed\n");
1946                 goto out_putdev;
1947         }
1948
1949         set_capacity(pd->disk, lba << 2);
1950         set_capacity(pd->bdev->bd_disk, lba << 2);
1951         bd_set_size(pd->bdev, (loff_t)lba << 11);
1952
1953         q = bdev_get_queue(pd->bdev);
1954         if (write) {
1955                 if ((ret = pkt_open_write(pd)))
1956                         goto out_putdev;
1957                 /*
1958                  * Some CDRW drives can not handle writes larger than one packet,
1959                  * even if the size is a multiple of the packet size.
1960                  */
1961                 spin_lock_irq(q->queue_lock);
1962                 blk_queue_max_sectors(q, pd->settings.size);
1963                 spin_unlock_irq(q->queue_lock);
1964                 set_bit(PACKET_WRITABLE, &pd->flags);
1965         } else {
1966                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1967                 clear_bit(PACKET_WRITABLE, &pd->flags);
1968         }
1969
1970         if ((ret = pkt_set_segment_merging(pd, q)))
1971                 goto out_putdev;
1972
1973         if (write)
1974                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1975
1976         return 0;
1977
1978 out_putdev:
1979         blkdev_put(pd->bdev);
1980 out:
1981         return ret;
1982 }
1983
1984 /*
1985  * called when the device is closed. makes sure that the device flushes
1986  * the internal cache before we close.
1987  */
1988 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
1989 {
1990         if (flush && pkt_flush_cache(pd))
1991                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
1992
1993         pkt_lock_door(pd, 0);
1994
1995         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1996         blkdev_put(pd->bdev);
1997 }
1998
1999 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2000 {
2001         if (dev_minor >= MAX_WRITERS)
2002                 return NULL;
2003         return pkt_devs[dev_minor];
2004 }
2005
2006 static int pkt_open(struct inode *inode, struct file *file)
2007 {
2008         struct pktcdvd_device *pd = NULL;
2009         int ret;
2010
2011         VPRINTK("pktcdvd: entering open\n");
2012
2013         down(&ctl_mutex);
2014         pd = pkt_find_dev_from_minor(iminor(inode));
2015         if (!pd) {
2016                 ret = -ENODEV;
2017                 goto out;
2018         }
2019         BUG_ON(pd->refcnt < 0);
2020
2021         pd->refcnt++;
2022         if (pd->refcnt == 1) {
2023                 if (pkt_open_dev(pd, file->f_mode & FMODE_WRITE)) {
2024                         ret = -EIO;
2025                         goto out_dec;
2026                 }
2027                 /*
2028                  * needed here as well, since ext2 (among others) may change
2029                  * the blocksize at mount time
2030                  */
2031                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2032         }
2033
2034         up(&ctl_mutex);
2035         return 0;
2036
2037 out_dec:
2038         pd->refcnt--;
2039 out:
2040         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2041         up(&ctl_mutex);
2042         return ret;
2043 }
2044
2045 static int pkt_close(struct inode *inode, struct file *file)
2046 {
2047         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2048         int ret = 0;
2049
2050         down(&ctl_mutex);
2051         pd->refcnt--;
2052         BUG_ON(pd->refcnt < 0);
2053         if (pd->refcnt == 0) {
2054                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2055                 pkt_release_dev(pd, flush);
2056         }
2057         up(&ctl_mutex);
2058         return ret;
2059 }
2060
2061
2062 static void *psd_pool_alloc(unsigned int __nocast gfp_mask, void *data)
2063 {
2064         return kmalloc(sizeof(struct packet_stacked_data), gfp_mask);
2065 }
2066
2067 static void psd_pool_free(void *ptr, void *data)
2068 {
2069         kfree(ptr);
2070 }
2071
2072 static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int err)
2073 {
2074         struct packet_stacked_data *psd = bio->bi_private;
2075         struct pktcdvd_device *pd = psd->pd;
2076
2077         if (bio->bi_size)
2078                 return 1;
2079
2080         bio_put(bio);
2081         bio_endio(psd->bio, psd->bio->bi_size, err);
2082         mempool_free(psd, psd_pool);
2083         pkt_bio_finished(pd);
2084         return 0;
2085 }
2086
2087 static int pkt_make_request(request_queue_t *q, struct bio *bio)
2088 {
2089         struct pktcdvd_device *pd;
2090         char b[BDEVNAME_SIZE];
2091         sector_t zone;
2092         struct packet_data *pkt;
2093         int was_empty, blocked_bio;
2094         struct pkt_rb_node *node;
2095
2096         pd = q->queuedata;
2097         if (!pd) {
2098                 printk("pktcdvd: %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2099                 goto end_io;
2100         }
2101
2102         /*
2103          * Clone READ bios so we can have our own bi_end_io callback.
2104          */
2105         if (bio_data_dir(bio) == READ) {
2106                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2107                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2108
2109                 psd->pd = pd;
2110                 psd->bio = bio;
2111                 cloned_bio->bi_bdev = pd->bdev;
2112                 cloned_bio->bi_private = psd;
2113                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2114                 pd->stats.secs_r += bio->bi_size >> 9;
2115                 pkt_queue_bio(pd, cloned_bio, 1);
2116                 return 0;
2117         }
2118
2119         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2120                 printk("pktcdvd: WRITE for ro device %s (%llu)\n",
2121                         pd->name, (unsigned long long)bio->bi_sector);
2122                 goto end_io;
2123         }
2124
2125         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2126                 printk("pktcdvd: wrong bio size\n");
2127                 goto end_io;
2128         }
2129
2130         blk_queue_bounce(q, &bio);
2131
2132         zone = ZONE(bio->bi_sector, pd);
2133         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2134                 (unsigned long long)bio->bi_sector,
2135                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2136
2137         /* Check if we have to split the bio */
2138         {
2139                 struct bio_pair *bp;
2140                 sector_t last_zone;
2141                 int first_sectors;
2142
2143                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2144                 if (last_zone != zone) {
2145                         BUG_ON(last_zone != zone + pd->settings.size);
2146                         first_sectors = last_zone - bio->bi_sector;
2147                         bp = bio_split(bio, bio_split_pool, first_sectors);
2148                         BUG_ON(!bp);
2149                         pkt_make_request(q, &bp->bio1);
2150                         pkt_make_request(q, &bp->bio2);
2151                         bio_pair_release(bp);
2152                         return 0;
2153                 }
2154         }
2155
2156         /*
2157          * If we find a matching packet in state WAITING or READ_WAIT, we can
2158          * just append this bio to that packet.
2159          */
2160         spin_lock(&pd->cdrw.active_list_lock);
2161         blocked_bio = 0;
2162         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2163                 if (pkt->sector == zone) {
2164                         spin_lock(&pkt->lock);
2165                         if ((pkt->state == PACKET_WAITING_STATE) ||
2166                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2167                                 pkt_add_list_last(bio, &pkt->orig_bios,
2168                                                   &pkt->orig_bios_tail);
2169                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2170                                 if ((pkt->write_size >= pkt->frames) &&
2171                                     (pkt->state == PACKET_WAITING_STATE)) {
2172                                         atomic_inc(&pkt->run_sm);
2173                                         wake_up(&pd->wqueue);
2174                                 }
2175                                 spin_unlock(&pkt->lock);
2176                                 spin_unlock(&pd->cdrw.active_list_lock);
2177                                 return 0;
2178                         } else {
2179                                 blocked_bio = 1;
2180                         }
2181                         spin_unlock(&pkt->lock);
2182                 }
2183         }
2184         spin_unlock(&pd->cdrw.active_list_lock);
2185
2186         /*
2187          * No matching packet found. Store the bio in the work queue.
2188          */
2189         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2190         BUG_ON(!node);
2191         node->bio = bio;
2192         spin_lock(&pd->lock);
2193         BUG_ON(pd->bio_queue_size < 0);
2194         was_empty = (pd->bio_queue_size == 0);
2195         pkt_rbtree_insert(pd, node);
2196         spin_unlock(&pd->lock);
2197
2198         /*
2199          * Wake up the worker thread.
2200          */
2201         atomic_set(&pd->scan_queue, 1);
2202         if (was_empty) {
2203                 /* This wake_up is required for correct operation */
2204                 wake_up(&pd->wqueue);
2205         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2206                 /*
2207                  * This wake up is not required for correct operation,
2208                  * but improves performance in some cases.
2209                  */
2210                 wake_up(&pd->wqueue);
2211         }
2212         return 0;
2213 end_io:
2214         bio_io_error(bio, bio->bi_size);
2215         return 0;
2216 }
2217
2218
2219
2220 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2221 {
2222         struct pktcdvd_device *pd = q->queuedata;
2223         sector_t zone = ZONE(bio->bi_sector, pd);
2224         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2225         int remaining = (pd->settings.size << 9) - used;
2226         int remaining2;
2227
2228         /*
2229          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2230          * boundary, pkt_make_request() will split the bio.
2231          */
2232         remaining2 = PAGE_SIZE - bio->bi_size;
2233         remaining = max(remaining, remaining2);
2234
2235         BUG_ON(remaining < 0);
2236         return remaining;
2237 }
2238
2239 static void pkt_init_queue(struct pktcdvd_device *pd)
2240 {
2241         request_queue_t *q = pd->disk->queue;
2242
2243         blk_queue_make_request(q, pkt_make_request);
2244         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2245         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2246         blk_queue_merge_bvec(q, pkt_merge_bvec);
2247         q->queuedata = pd;
2248 }
2249
2250 static int pkt_seq_show(struct seq_file *m, void *p)
2251 {
2252         struct pktcdvd_device *pd = m->private;
2253         char *msg;
2254         char bdev_buf[BDEVNAME_SIZE];
2255         int states[PACKET_NUM_STATES];
2256
2257         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2258                    bdevname(pd->bdev, bdev_buf));
2259
2260         seq_printf(m, "\nSettings:\n");
2261         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2262
2263         if (pd->settings.write_type == 0)
2264                 msg = "Packet";
2265         else
2266                 msg = "Unknown";
2267         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2268
2269         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2270         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2271
2272         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2273
2274         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2275                 msg = "Mode 1";
2276         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2277                 msg = "Mode 2";
2278         else
2279                 msg = "Unknown";
2280         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2281
2282         seq_printf(m, "\nStatistics:\n");
2283         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2284         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2285         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2286         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2287         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2288
2289         seq_printf(m, "\nMisc:\n");
2290         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2291         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2292         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2293         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2294         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2295         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2296
2297         seq_printf(m, "\nQueue state:\n");
2298         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2299         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2300         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2301
2302         pkt_count_states(pd, states);
2303         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2304                    states[0], states[1], states[2], states[3], states[4], states[5]);
2305
2306         return 0;
2307 }
2308
2309 static int pkt_seq_open(struct inode *inode, struct file *file)
2310 {
2311         return single_open(file, pkt_seq_show, PDE(inode)->data);
2312 }
2313
2314 static struct file_operations pkt_proc_fops = {
2315         .open   = pkt_seq_open,
2316         .read   = seq_read,
2317         .llseek = seq_lseek,
2318         .release = single_release
2319 };
2320
2321 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2322 {
2323         int i;
2324         int ret = 0;
2325         char b[BDEVNAME_SIZE];
2326         struct proc_dir_entry *proc;
2327         struct block_device *bdev;
2328
2329         if (pd->pkt_dev == dev) {
2330                 printk("pktcdvd: Recursive setup not allowed\n");
2331                 return -EBUSY;
2332         }
2333         for (i = 0; i < MAX_WRITERS; i++) {
2334                 struct pktcdvd_device *pd2 = pkt_devs[i];
2335                 if (!pd2)
2336                         continue;
2337                 if (pd2->bdev->bd_dev == dev) {
2338                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2339                         return -EBUSY;
2340                 }
2341                 if (pd2->pkt_dev == dev) {
2342                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2343                         return -EBUSY;
2344                 }
2345         }
2346
2347         bdev = bdget(dev);
2348         if (!bdev)
2349                 return -ENOMEM;
2350         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2351         if (ret)
2352                 return ret;
2353
2354         /* This is safe, since we have a reference from open(). */
2355         __module_get(THIS_MODULE);
2356
2357         if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2358                 printk("pktcdvd: not enough memory for buffers\n");
2359                 ret = -ENOMEM;
2360                 goto out_mem;
2361         }
2362
2363         pd->bdev = bdev;
2364         set_blocksize(bdev, CD_FRAMESIZE);
2365
2366         pkt_init_queue(pd);
2367
2368         atomic_set(&pd->cdrw.pending_bios, 0);
2369         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2370         if (IS_ERR(pd->cdrw.thread)) {
2371                 printk("pktcdvd: can't start kernel thread\n");
2372                 ret = -ENOMEM;
2373                 goto out_thread;
2374         }
2375
2376         proc = create_proc_entry(pd->name, 0, pkt_proc);
2377         if (proc) {
2378                 proc->data = pd;
2379                 proc->proc_fops = &pkt_proc_fops;
2380         }
2381         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2382         return 0;
2383
2384 out_thread:
2385         pkt_shrink_pktlist(pd);
2386 out_mem:
2387         blkdev_put(bdev);
2388         /* This is safe: open() is still holding a reference. */
2389         module_put(THIS_MODULE);
2390         return ret;
2391 }
2392
2393 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2394 {
2395         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2396
2397         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2398         BUG_ON(!pd);
2399
2400         switch (cmd) {
2401         /*
2402          * forward selected CDROM ioctls to CD-ROM, for UDF
2403          */
2404         case CDROMMULTISESSION:
2405         case CDROMREADTOCENTRY:
2406         case CDROM_LAST_WRITTEN:
2407         case CDROM_SEND_PACKET:
2408         case SCSI_IOCTL_SEND_COMMAND:
2409                 return ioctl_by_bdev(pd->bdev, cmd, arg);
2410
2411         case CDROMEJECT:
2412                 /*
2413                  * The door gets locked when the device is opened, so we
2414                  * have to unlock it or else the eject command fails.
2415                  */
2416                 pkt_lock_door(pd, 0);
2417                 return ioctl_by_bdev(pd->bdev, cmd, arg);
2418
2419         default:
2420                 printk("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2421                 return -ENOTTY;
2422         }
2423
2424         return 0;
2425 }
2426
2427 static int pkt_media_changed(struct gendisk *disk)
2428 {
2429         struct pktcdvd_device *pd = disk->private_data;
2430         struct gendisk *attached_disk;
2431
2432         if (!pd)
2433                 return 0;
2434         if (!pd->bdev)
2435                 return 0;
2436         attached_disk = pd->bdev->bd_disk;
2437         if (!attached_disk)
2438                 return 0;
2439         return attached_disk->fops->media_changed(attached_disk);
2440 }
2441
2442 static struct block_device_operations pktcdvd_ops = {
2443         .owner =                THIS_MODULE,
2444         .open =                 pkt_open,
2445         .release =              pkt_close,
2446         .ioctl =                pkt_ioctl,
2447         .media_changed =        pkt_media_changed,
2448 };
2449
2450 /*
2451  * Set up mapping from pktcdvd device to CD-ROM device.
2452  */
2453 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2454 {
2455         int idx;
2456         int ret = -ENOMEM;
2457         struct pktcdvd_device *pd;
2458         struct gendisk *disk;
2459         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2460
2461         for (idx = 0; idx < MAX_WRITERS; idx++)
2462                 if (!pkt_devs[idx])
2463                         break;
2464         if (idx == MAX_WRITERS) {
2465                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2466                 return -EBUSY;
2467         }
2468
2469         pd = kmalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2470         if (!pd)
2471                 return ret;
2472         memset(pd, 0, sizeof(struct pktcdvd_device));
2473
2474         pd->rb_pool = mempool_create(PKT_RB_POOL_SIZE, pkt_rb_alloc, pkt_rb_free, NULL);
2475         if (!pd->rb_pool)
2476                 goto out_mem;
2477
2478         disk = alloc_disk(1);
2479         if (!disk)
2480                 goto out_mem;
2481         pd->disk = disk;
2482
2483         spin_lock_init(&pd->lock);
2484         spin_lock_init(&pd->iosched.lock);
2485         sprintf(pd->name, "pktcdvd%d", idx);
2486         init_waitqueue_head(&pd->wqueue);
2487         pd->bio_queue = RB_ROOT;
2488
2489         disk->major = pkt_major;
2490         disk->first_minor = idx;
2491         disk->fops = &pktcdvd_ops;
2492         disk->flags = GENHD_FL_REMOVABLE;
2493         sprintf(disk->disk_name, "pktcdvd%d", idx);
2494         disk->private_data = pd;
2495         disk->queue = blk_alloc_queue(GFP_KERNEL);
2496         if (!disk->queue)
2497                 goto out_mem2;
2498
2499         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2500         ret = pkt_new_dev(pd, dev);
2501         if (ret)
2502                 goto out_new_dev;
2503
2504         add_disk(disk);
2505         pkt_devs[idx] = pd;
2506         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2507         return 0;
2508
2509 out_new_dev:
2510         blk_put_queue(disk->queue);
2511 out_mem2:
2512         put_disk(disk);
2513 out_mem:
2514         if (pd->rb_pool)
2515                 mempool_destroy(pd->rb_pool);
2516         kfree(pd);
2517         return ret;
2518 }
2519
2520 /*
2521  * Tear down mapping from pktcdvd device to CD-ROM device.
2522  */
2523 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2524 {
2525         struct pktcdvd_device *pd;
2526         int idx;
2527         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2528
2529         for (idx = 0; idx < MAX_WRITERS; idx++) {
2530                 pd = pkt_devs[idx];
2531                 if (pd && (pd->pkt_dev == pkt_dev))
2532                         break;
2533         }
2534         if (idx == MAX_WRITERS) {
2535                 DPRINTK("pktcdvd: dev not setup\n");
2536                 return -ENXIO;
2537         }
2538
2539         if (pd->refcnt > 0)
2540                 return -EBUSY;
2541
2542         if (!IS_ERR(pd->cdrw.thread))
2543                 kthread_stop(pd->cdrw.thread);
2544
2545         blkdev_put(pd->bdev);
2546
2547         pkt_shrink_pktlist(pd);
2548
2549         remove_proc_entry(pd->name, pkt_proc);
2550         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2551
2552         del_gendisk(pd->disk);
2553         blk_put_queue(pd->disk->queue);
2554         put_disk(pd->disk);
2555
2556         pkt_devs[idx] = NULL;
2557         mempool_destroy(pd->rb_pool);
2558         kfree(pd);
2559
2560         /* This is safe: open() is still holding a reference. */
2561         module_put(THIS_MODULE);
2562         return 0;
2563 }
2564
2565 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2566 {
2567         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2568         if (pd) {
2569                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2570                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2571         } else {
2572                 ctrl_cmd->dev = 0;
2573                 ctrl_cmd->pkt_dev = 0;
2574         }
2575         ctrl_cmd->num_devices = MAX_WRITERS;
2576 }
2577
2578 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2579 {
2580         void __user *argp = (void __user *)arg;
2581         struct pkt_ctrl_command ctrl_cmd;
2582         int ret = 0;
2583
2584         if (cmd != PACKET_CTRL_CMD)
2585                 return -ENOTTY;
2586
2587         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2588                 return -EFAULT;
2589
2590         switch (ctrl_cmd.command) {
2591         case PKT_CTRL_CMD_SETUP:
2592                 if (!capable(CAP_SYS_ADMIN))
2593                         return -EPERM;
2594                 down(&ctl_mutex);
2595                 ret = pkt_setup_dev(&ctrl_cmd);
2596                 up(&ctl_mutex);
2597                 break;
2598         case PKT_CTRL_CMD_TEARDOWN:
2599                 if (!capable(CAP_SYS_ADMIN))
2600                         return -EPERM;
2601                 down(&ctl_mutex);
2602                 ret = pkt_remove_dev(&ctrl_cmd);
2603                 up(&ctl_mutex);
2604                 break;
2605         case PKT_CTRL_CMD_STATUS:
2606                 down(&ctl_mutex);
2607                 pkt_get_status(&ctrl_cmd);
2608                 up(&ctl_mutex);
2609                 break;
2610         default:
2611                 return -ENOTTY;
2612         }
2613
2614         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2615                 return -EFAULT;
2616         return ret;
2617 }
2618
2619
2620 static struct file_operations pkt_ctl_fops = {
2621         .ioctl   = pkt_ctl_ioctl,
2622         .owner   = THIS_MODULE,
2623 };
2624
2625 static struct miscdevice pkt_misc = {
2626         .minor          = MISC_DYNAMIC_MINOR,
2627         .name           = "pktcdvd",
2628         .devfs_name     = "pktcdvd/control",
2629         .fops           = &pkt_ctl_fops
2630 };
2631
2632 static int __init pkt_init(void)
2633 {
2634         int ret;
2635
2636         psd_pool = mempool_create(PSD_POOL_SIZE, psd_pool_alloc, psd_pool_free, NULL);
2637         if (!psd_pool)
2638                 return -ENOMEM;
2639
2640         ret = register_blkdev(pkt_major, "pktcdvd");
2641         if (ret < 0) {
2642                 printk("pktcdvd: Unable to register block device\n");
2643                 goto out2;
2644         }
2645         if (!pkt_major)
2646                 pkt_major = ret;
2647
2648         ret = misc_register(&pkt_misc);
2649         if (ret) {
2650                 printk("pktcdvd: Unable to register misc device\n");
2651                 goto out;
2652         }
2653
2654         init_MUTEX(&ctl_mutex);
2655
2656         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2657
2658         DPRINTK("pktcdvd: %s\n", VERSION_CODE);
2659         return 0;
2660
2661 out:
2662         unregister_blkdev(pkt_major, "pktcdvd");
2663 out2:
2664         mempool_destroy(psd_pool);
2665         return ret;
2666 }
2667
2668 static void __exit pkt_exit(void)
2669 {
2670         remove_proc_entry("pktcdvd", proc_root_driver);
2671         misc_deregister(&pkt_misc);
2672         unregister_blkdev(pkt_major, "pktcdvd");
2673         mempool_destroy(psd_pool);
2674 }
2675
2676 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2677 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2678 MODULE_LICENSE("GPL");
2679
2680 module_init(pkt_init);
2681 module_exit(pkt_exit);