drivers/block/pktcdvd.c

   1 /*
   2  * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
   3  * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
   4  *
   5  * May be copied or modified under the terms of the GNU General Public
   6  * License.  See linux/COPYING for more information.
   7  *
   8  * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
   9  * DVD-RAM devices.
  10  *
  11  * Theory of operation:
  12  *
  13  * At the lowest level, there is the standard driver for the CD/DVD device,
  14  * typically ide-cd.c or sr.c. This driver can handle read and write requests,
  15  * but it doesn't know anything about the special restrictions that apply to
  16  * packet writing. One restriction is that write requests must be aligned to
  17  * packet boundaries on the physical media, and the size of a write request
  18  * must be equal to the packet size. Another restriction is that a
  19  * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
  20  * command, if the previous command was a write.
  21  *
  22  * The purpose of the packet writing driver is to hide these restrictions from
  23  * higher layers, such as file systems, and present a block device that can be
  24  * randomly read and written using 2kB-sized blocks.
  25  *
  26  * The lowest layer in the packet writing driver is the packet I/O scheduler.
  27  * Its data is defined by the struct packet_iosched and includes two bio
  28  * queues with pending read and write requests. These queues are processed
  29  * by the pkt_iosched_process_queue() function. The write requests in this
  30  * queue are already properly aligned and sized. This layer is responsible for
  31  * issuing the flush cache commands and scheduling the I/O in a good order.
  32  *
  33  * The next layer transforms unaligned write requests to aligned writes. This
  34  * transformation requires reading missing pieces of data from the underlying
  35  * block device, assembling the pieces to full packets and queuing them to the
  36  * packet I/O scheduler.
  37  *
  38  * At the top layer there is a custom make_request_fn function that forwards
  39  * read requests directly to the iosched queue and puts write requests in the
  40  * unaligned write queue. A kernel thread performs the necessary read
  41  * gathering to convert the unaligned writes to aligned writes and then feeds
  42  * them to the packet I/O scheduler.
  43  *
  44  *************************************************************************/
  45
  46 #include <linux/pktcdvd.h>
  47 #include <linux/config.h>
  48 #include <linux/module.h>
  49 #include <linux/types.h>
  50 #include <linux/kernel.h>
  51 #include <linux/kthread.h>
  52 #include <linux/errno.h>
  53 #include <linux/spinlock.h>
  54 #include <linux/file.h>
  55 #include <linux/proc_fs.h>
  56 #include <linux/seq_file.h>
  57 #include <linux/miscdevice.h>
  58 #include <linux/suspend.h>
  59 #include <scsi/scsi_cmnd.h>
  60 #include <scsi/scsi_ioctl.h>
  61
  62 #include <asm/uaccess.h>
  63
  64 #if PACKET_DEBUG
  65 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  66 #else
  67 #define DPRINTK(fmt, args...)
  68 #endif
  69
  70 #if PACKET_DEBUG > 1
  71 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  72 #else
  73 #define VPRINTK(fmt, args...)
  74 #endif
  75
  76 #define MAX_SPEED 0xffff
  77
  78 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  79
  80 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  81 static struct proc_dir_entry *pkt_proc;
  82 static int pkt_major;
  83 static struct semaphore ctl_mutex;      /* Serialize open/close/setup/teardown */
  84 static mempool_t *psd_pool;
  85
  86
  87 static void pkt_bio_finished(struct pktcdvd_device *pd)
  88 {
  89         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
  90         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
  91                 VPRINTK("pktcdvd: queue empty\n");
  92                 atomic_set(&pd->iosched.attention, 1);
  93                 wake_up(&pd->wqueue);
  94         }
  95 }
  96
  97 static void pkt_bio_destructor(struct bio *bio)
  98 {
  99         kfree(bio->bi_io_vec);
 100         kfree(bio);
 101 }
 102
 103 static struct bio *pkt_bio_alloc(int nr_iovecs)
 104 {
 105         struct bio_vec *bvl = NULL;
 106         struct bio *bio;
 107
 108         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
 109         if (!bio)
 110                 goto no_bio;
 111         bio_init(bio);
 112
 113         bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL);
 114         if (!bvl)
 115                 goto no_bvl;
 116
 117         bio->bi_max_vecs = nr_iovecs;
 118         bio->bi_io_vec = bvl;
 119         bio->bi_destructor = pkt_bio_destructor;
 120
 121         return bio;
 122
 123  no_bvl:
 124         kfree(bio);
 125  no_bio:
 126         return NULL;
 127 }
 128
 129 /*
 130  * Allocate a packet_data struct
 131  */
 132 static struct packet_data *pkt_alloc_packet_data(void)
 133 {
 134         int i;
 135         struct packet_data *pkt;
 136
 137         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 138         if (!pkt)
 139                 goto no_pkt;
 140
 141         pkt->w_bio = pkt_bio_alloc(PACKET_MAX_SIZE);
 142         if (!pkt->w_bio)
 143                 goto no_bio;
 144
 145         for (i = 0; i < PAGES_PER_PACKET; i++) {
 146                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 147                 if (!pkt->pages[i])
 148                         goto no_page;
 149         }
 150
 151         spin_lock_init(&pkt->lock);
 152
 153         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 154                 struct bio *bio = pkt_bio_alloc(1);
 155                 if (!bio)
 156                         goto no_rd_bio;
 157                 pkt->r_bios[i] = bio;
 158         }
 159
 160         return pkt;
 161
 162 no_rd_bio:
 163         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 164                 struct bio *bio = pkt->r_bios[i];
 165                 if (bio)
 166                         bio_put(bio);
 167         }
 168
 169 no_page:
 170         for (i = 0; i < PAGES_PER_PACKET; i++)
 171                 if (pkt->pages[i])
 172                         __free_page(pkt->pages[i]);
 173         bio_put(pkt->w_bio);
 174 no_bio:
 175         kfree(pkt);
 176 no_pkt:
 177         return NULL;
 178 }
 179
 180 /*
 181  * Free a packet_data struct
 182  */
 183 static void pkt_free_packet_data(struct packet_data *pkt)
 184 {
 185         int i;
 186
 187         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 188                 struct bio *bio = pkt->r_bios[i];
 189                 if (bio)
 190                         bio_put(bio);
 191         }
 192         for (i = 0; i < PAGES_PER_PACKET; i++)
 193                 __free_page(pkt->pages[i]);
 194         bio_put(pkt->w_bio);
 195         kfree(pkt);
 196 }
 197
 198 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 199 {
 200         struct packet_data *pkt, *next;
 201
 202         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 203
 204         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 205                 pkt_free_packet_data(pkt);
 206         }
 207 }
 208
 209 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 210 {
 211         struct packet_data *pkt;
 212
 213         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 214         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
 215         spin_lock_init(&pd->cdrw.active_list_lock);
 216         while (nr_packets > 0) {
 217                 pkt = pkt_alloc_packet_data();
 218                 if (!pkt) {
 219                         pkt_shrink_pktlist(pd);
 220                         return 0;
 221                 }
 222                 pkt->id = nr_packets;
 223                 pkt->pd = pd;
 224                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 225                 nr_packets--;
 226         }
 227         return 1;
 228 }
 229
 230 static void *pkt_rb_alloc(gfp_t gfp_mask, void *data)
 231 {
 232         return kmalloc(sizeof(struct pkt_rb_node), gfp_mask);
 233 }
 234
 235 static void pkt_rb_free(void *ptr, void *data)
 236 {
 237         kfree(ptr);
 238 }
 239
 240 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 241 {
 242         struct rb_node *n = rb_next(&node->rb_node);
 243         if (!n)
 244                 return NULL;
 245         return rb_entry(n, struct pkt_rb_node, rb_node);
 246 }
 247
 248 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 249 {
 250         rb_erase(&node->rb_node, &pd->bio_queue);
 251         mempool_free(node, pd->rb_pool);
 252         pd->bio_queue_size--;
 253         BUG_ON(pd->bio_queue_size < 0);
 254 }
 255
 256 /*
 257  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 258  */
 259 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 260 {
 261         struct rb_node *n = pd->bio_queue.rb_node;
 262         struct rb_node *next;
 263         struct pkt_rb_node *tmp;
 264
 265         if (!n) {
 266                 BUG_ON(pd->bio_queue_size > 0);
 267                 return NULL;
 268         }
 269
 270         for (;;) {
 271                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 272                 if (s <= tmp->bio->bi_sector)
 273                         next = n->rb_left;
 274                 else
 275                         next = n->rb_right;
 276                 if (!next)
 277                         break;
 278                 n = next;
 279         }
 280
 281         if (s > tmp->bio->bi_sector) {
 282                 tmp = pkt_rbtree_next(tmp);
 283                 if (!tmp)
 284                         return NULL;
 285         }
 286         BUG_ON(s > tmp->bio->bi_sector);
 287         return tmp;
 288 }
 289
 290 /*
 291  * Insert a node into the pd->bio_queue rb tree.
 292  */
 293 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 294 {
 295         struct rb_node **p = &pd->bio_queue.rb_node;
 296         struct rb_node *parent = NULL;
 297         sector_t s = node->bio->bi_sector;
 298         struct pkt_rb_node *tmp;
 299
 300         while (*p) {
 301                 parent = *p;
 302                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 303                 if (s < tmp->bio->bi_sector)
 304                         p = &(*p)->rb_left;
 305                 else
 306                         p = &(*p)->rb_right;
 307         }
 308         rb_link_node(&node->rb_node, parent, p);
 309         rb_insert_color(&node->rb_node, &pd->bio_queue);
 310         pd->bio_queue_size++;
 311 }
 312
 313 /*
 314  * Add a bio to a single linked list defined by its head and tail pointers.
 315  */
 316 static void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
 317 {
 318         bio->bi_next = NULL;
 319         if (*list_tail) {
 320                 BUG_ON((*list_head) == NULL);
 321                 (*list_tail)->bi_next = bio;
 322                 (*list_tail) = bio;
 323         } else {
 324                 BUG_ON((*list_head) != NULL);
 325                 (*list_head) = bio;
 326                 (*list_tail) = bio;
 327         }
 328 }
 329
 330 /*
 331  * Remove and return the first bio from a single linked list defined by its
 332  * head and tail pointers.
 333  */
 334 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
 335 {
 336         struct bio *bio;
 337
 338         if (*list_head == NULL)
 339                 return NULL;
 340
 341         bio = *list_head;
 342         *list_head = bio->bi_next;
 343         if (*list_head == NULL)
 344                 *list_tail = NULL;
 345
 346         bio->bi_next = NULL;
 347         return bio;
 348 }
 349
 350 /*
 351  * Send a packet_command to the underlying block device and
 352  * wait for completion.
 353  */
 354 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 355 {
 356         char sense[SCSI_SENSE_BUFFERSIZE];
 357         request_queue_t *q;
 358         struct request *rq;
 359         DECLARE_COMPLETION(wait);
 360         int err = 0;
 361
 362         q = bdev_get_queue(pd->bdev);
 363
 364         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ,
 365                              __GFP_WAIT);
 366         rq->errors = 0;
 367         rq->rq_disk = pd->bdev->bd_disk;
 368         rq->bio = NULL;
 369         rq->buffer = NULL;
 370         rq->timeout = 60*HZ;
 371         rq->data = cgc->buffer;
 372         rq->data_len = cgc->buflen;
 373         rq->sense = sense;
 374         memset(sense, 0, sizeof(sense));
 375         rq->sense_len = 0;
 376         rq->flags |= REQ_BLOCK_PC | REQ_HARDBARRIER;
 377         if (cgc->quiet)
 378                 rq->flags |= REQ_QUIET;
 379         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 380         if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
 381                 memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);
 382
 383         rq->ref_count++;
 384         rq->flags |= REQ_NOMERGE;
 385         rq->waiting = &wait;
 386         rq->end_io = blk_end_sync_rq;
 387         elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
 388         generic_unplug_device(q);
 389         wait_for_completion(&wait);
 390
 391         if (rq->errors)
 392                 err = -EIO;
 393
 394         blk_put_request(rq);
 395         return err;
 396 }
 397
 398 /*
 399  * A generic sense dump / resolve mechanism should be implemented across
 400  * all ATAPI + SCSI devices.
 401  */
 402 static void pkt_dump_sense(struct packet_command *cgc)
 403 {
 404         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 405                                  "Medium error", "Hardware error", "Illegal request",
 406                                  "Unit attention", "Data protect", "Blank check" };
 407         int i;
 408         struct request_sense *sense = cgc->sense;
 409
 410         printk("pktcdvd:");
 411         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 412                 printk(" %02x", cgc->cmd[i]);
 413         printk(" - ");
 414
 415         if (sense == NULL) {
 416                 printk("no sense\n");
 417                 return;
 418         }
 419
 420         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 421
 422         if (sense->sense_key > 8) {
 423                 printk(" (INVALID)\n");
 424                 return;
 425         }
 426
 427         printk(" (%s)\n", info[sense->sense_key]);
 428 }
 429
 430 /*
 431  * flush the drive cache to media
 432  */
 433 static int pkt_flush_cache(struct pktcdvd_device *pd)
 434 {
 435         struct packet_command cgc;
 436
 437         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 438         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 439         cgc.quiet = 1;
 440
 441         /*
 442          * the IMMED bit -- we default to not setting it, although that
 443          * would allow a much faster close, this is safer
 444          */
 445 #if 0
 446         cgc.cmd[1] = 1 << 1;
 447 #endif
 448         return pkt_generic_packet(pd, &cgc);
 449 }
 450
 451 /*
 452  * speed is given as the normal factor, e.g. 4 for 4x
 453  */
 454 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
 455 {
 456         struct packet_command cgc;
 457         struct request_sense sense;
 458         int ret;
 459
 460         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 461         cgc.sense = &sense;
 462         cgc.cmd[0] = GPCMD_SET_SPEED;
 463         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 464         cgc.cmd[3] = read_speed & 0xff;
 465         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 466         cgc.cmd[5] = write_speed & 0xff;
 467
 468         if ((ret = pkt_generic_packet(pd, &cgc)))
 469                 pkt_dump_sense(&cgc);
 470
 471         return ret;
 472 }
 473
 474 /*
 475  * Queue a bio for processing by the low-level CD device. Must be called
 476  * from process context.
 477  */
 478 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 479 {
 480         spin_lock(&pd->iosched.lock);
 481         if (bio_data_dir(bio) == READ) {
 482                 pkt_add_list_last(bio, &pd->iosched.read_queue,
 483                                   &pd->iosched.read_queue_tail);
 484         } else {
 485                 pkt_add_list_last(bio, &pd->iosched.write_queue,
 486                                   &pd->iosched.write_queue_tail);
 487         }
 488         spin_unlock(&pd->iosched.lock);
 489
 490         atomic_set(&pd->iosched.attention, 1);
 491         wake_up(&pd->wqueue);
 492 }
 493
 494 /*
 495  * Process the queued read/write requests. This function handles special
 496  * requirements for CDRW drives:
 497  * - A cache flush command must be inserted before a read request if the
 498  *   previous request was a write.
 499  * - Switching between reading and writing is slow, so don't do it more often
 500  *   than necessary.
 501  * - Optimize for throughput at the expense of latency. This means that streaming
 502  *   writes will never be interrupted by a read, but if the drive has to seek
 503  *   before the next write, switch to reading instead if there are any pending
 504  *   read requests.
 505  * - Set the read speed according to current usage pattern. When only reading
 506  *   from the device, it's best to use the highest possible read speed, but
 507  *   when switching often between reading and writing, it's better to have the
 508  *   same read and write speeds.
 509  */
 510 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 511 {
 512
 513         if (atomic_read(&pd->iosched.attention) == 0)
 514                 return;
 515         atomic_set(&pd->iosched.attention, 0);
 516
 517         for (;;) {
 518                 struct bio *bio;
 519                 int reads_queued, writes_queued;
 520
 521                 spin_lock(&pd->iosched.lock);
 522                 reads_queued = (pd->iosched.read_queue != NULL);
 523                 writes_queued = (pd->iosched.write_queue != NULL);
 524                 spin_unlock(&pd->iosched.lock);
 525
 526                 if (!reads_queued && !writes_queued)
 527                         break;
 528
 529                 if (pd->iosched.writing) {
 530                         int need_write_seek = 1;
 531                         spin_lock(&pd->iosched.lock);
 532                         bio = pd->iosched.write_queue;
 533                         spin_unlock(&pd->iosched.lock);
 534                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 535                                 need_write_seek = 0;
 536                         if (need_write_seek && reads_queued) {
 537                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 538                                         VPRINTK("pktcdvd: write, waiting\n");
 539                                         break;
 540                                 }
 541                                 pkt_flush_cache(pd);
 542                                 pd->iosched.writing = 0;
 543                         }
 544                 } else {
 545                         if (!reads_queued && writes_queued) {
 546                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 547                                         VPRINTK("pktcdvd: read, waiting\n");
 548                                         break;
 549                                 }
 550                                 pd->iosched.writing = 1;
 551                         }
 552                 }
 553
 554                 spin_lock(&pd->iosched.lock);
 555                 if (pd->iosched.writing) {
 556                         bio = pkt_get_list_first(&pd->iosched.write_queue,
 557                                                  &pd->iosched.write_queue_tail);
 558                 } else {
 559                         bio = pkt_get_list_first(&pd->iosched.read_queue,
 560                                                  &pd->iosched.read_queue_tail);
 561                 }
 562                 spin_unlock(&pd->iosched.lock);
 563
 564                 if (!bio)
 565                         continue;
 566
 567                 if (bio_data_dir(bio) == READ)
 568                         pd->iosched.successive_reads += bio->bi_size >> 10;
 569                 else {
 570                         pd->iosched.successive_reads = 0;
 571                         pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
 572                 }
 573                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 574                         if (pd->read_speed == pd->write_speed) {
 575                                 pd->read_speed = MAX_SPEED;
 576                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 577                         }
 578                 } else {
 579                         if (pd->read_speed != pd->write_speed) {
 580                                 pd->read_speed = pd->write_speed;
 581                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 582                         }
 583                 }
 584
 585                 atomic_inc(&pd->cdrw.pending_bios);
 586                 generic_make_request(bio);
 587         }
 588 }
 589
 590 /*
 591  * Special care is needed if the underlying block device has a small
 592  * max_phys_segments value.
 593  */
 594 static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
 595 {
 596         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 597                 /*
 598                  * The cdrom device can handle one segment/frame
 599                  */
 600                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 601                 return 0;
 602         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
 603                 /*
 604                  * We can handle this case at the expense of some extra memory
 605                  * copies during write operations
 606                  */
 607                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 608                 return 0;
 609         } else {
 610                 printk("pktcdvd: cdrom max_phys_segments too small\n");
 611                 return -EIO;
 612         }
 613 }
 614
 615 /*
 616  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 617  */
 618 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 619 {
 620         unsigned int copy_size = CD_FRAMESIZE;
 621
 622         while (copy_size > 0) {
 623                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 624                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 625                         src_bvl->bv_offset + offs;
 626                 void *vto = page_address(dst_page) + dst_offs;
 627                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 628
 629                 BUG_ON(len < 0);
 630                 memcpy(vto, vfrom, len);
 631                 kunmap_atomic(vfrom, KM_USER0);
 632
 633                 seg++;
 634                 offs = 0;
 635                 dst_offs += len;
 636                 copy_size -= len;
 637         }
 638 }
 639
 640 /*
 641  * Copy all data for this packet to pkt->pages[], so that
 642  * a) The number of required segments for the write bio is minimized, which
 643  *    is necessary for some scsi controllers.
 644  * b) The data can be used as cache to avoid read requests if we receive a
 645  *    new write request for the same zone.
 646  */
 647 static void pkt_make_local_copy(struct packet_data *pkt, struct page **pages, int *offsets)
 648 {
 649         int f, p, offs;
 650
 651         /* Copy all data to pkt->pages[] */
 652         p = 0;
 653         offs = 0;
 654         for (f = 0; f < pkt->frames; f++) {
 655                 if (pages[f] != pkt->pages[p]) {
 656                         void *vfrom = kmap_atomic(pages[f], KM_USER0) + offsets[f];
 657                         void *vto = page_address(pkt->pages[p]) + offs;
 658                         memcpy(vto, vfrom, CD_FRAMESIZE);
 659                         kunmap_atomic(vfrom, KM_USER0);
 660                         pages[f] = pkt->pages[p];
 661                         offsets[f] = offs;
 662                 } else {
 663                         BUG_ON(offsets[f] != offs);
 664                 }
 665                 offs += CD_FRAMESIZE;
 666                 if (offs >= PAGE_SIZE) {
 667                         offs = 0;
 668                         p++;
 669                 }
 670         }
 671 }
 672
 673 static int pkt_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
 674 {
 675         struct packet_data *pkt = bio->bi_private;
 676         struct pktcdvd_device *pd = pkt->pd;
 677         BUG_ON(!pd);
 678
 679         if (bio->bi_size)
 680                 return 1;
 681
 682         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 683                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 684
 685         if (err)
 686                 atomic_inc(&pkt->io_errors);
 687         if (atomic_dec_and_test(&pkt->io_wait)) {
 688                 atomic_inc(&pkt->run_sm);
 689                 wake_up(&pd->wqueue);
 690         }
 691         pkt_bio_finished(pd);
 692
 693         return 0;
 694 }
 695
 696 static int pkt_end_io_packet_write(struct bio *bio, unsigned int bytes_done, int err)
 697 {
 698         struct packet_data *pkt = bio->bi_private;
 699         struct pktcdvd_device *pd = pkt->pd;
 700         BUG_ON(!pd);
 701
 702         if (bio->bi_size)
 703                 return 1;
 704
 705         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
 706
 707         pd->stats.pkt_ended++;
 708
 709         pkt_bio_finished(pd);
 710         atomic_dec(&pkt->io_wait);
 711         atomic_inc(&pkt->run_sm);
 712         wake_up(&pd->wqueue);
 713         return 0;
 714 }
 715
 716 /*
 717  * Schedule reads for the holes in a packet
 718  */
 719 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 720 {
 721         int frames_read = 0;
 722         struct bio *bio;
 723         int f;
 724         char written[PACKET_MAX_SIZE];
 725
 726         BUG_ON(!pkt->orig_bios);
 727
 728         atomic_set(&pkt->io_wait, 0);
 729         atomic_set(&pkt->io_errors, 0);
 730
 731         /*
 732          * Figure out which frames we need to read before we can write.
 733          */
 734         memset(written, 0, sizeof(written));
 735         spin_lock(&pkt->lock);
 736         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
 737                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
 738                 int num_frames = bio->bi_size / CD_FRAMESIZE;
 739                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
 740                 BUG_ON(first_frame < 0);
 741                 BUG_ON(first_frame + num_frames > pkt->frames);
 742                 for (f = first_frame; f < first_frame + num_frames; f++)
 743                         written[f] = 1;
 744         }
 745         spin_unlock(&pkt->lock);
 746
 747         if (pkt->cache_valid) {
 748                 VPRINTK("pkt_gather_data: zone %llx cached\n",
 749                         (unsigned long long)pkt->sector);
 750                 goto out_account;
 751         }
 752
 753         /*
 754          * Schedule reads for missing parts of the packet.
 755          */
 756         for (f = 0; f < pkt->frames; f++) {
 757                 int p, offset;
 758                 if (written[f])
 759                         continue;
 760                 bio = pkt->r_bios[f];
 761                 bio_init(bio);
 762                 bio->bi_max_vecs = 1;
 763                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 764                 bio->bi_bdev = pd->bdev;
 765                 bio->bi_end_io = pkt_end_io_read;
 766                 bio->bi_private = pkt;
 767
 768                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
 769                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 770                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
 771                         f, pkt->pages[p], offset);
 772                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
 773                         BUG();
 774
 775                 atomic_inc(&pkt->io_wait);
 776                 bio->bi_rw = READ;
 777                 pkt_queue_bio(pd, bio);
 778                 frames_read++;
 779         }
 780
 781 out_account:
 782         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
 783                 frames_read, (unsigned long long)pkt->sector);
 784         pd->stats.pkt_started++;
 785         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
 786 }
 787
 788 /*
 789  * Find a packet matching zone, or the least recently used packet if
 790  * there is no match.
 791  */
 792 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
 793 {
 794         struct packet_data *pkt;
 795
 796         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
 797                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
 798                         list_del_init(&pkt->list);
 799                         if (pkt->sector != zone)
 800                                 pkt->cache_valid = 0;
 801                         return pkt;
 802                 }
 803         }
 804         BUG();
 805         return NULL;
 806 }
 807
 808 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 809 {
 810         if (pkt->cache_valid) {
 811                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 812         } else {
 813                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
 814         }
 815 }
 816
 817 /*
 818  * recover a failed write, query for relocation if possible
 819  *
 820  * returns 1 if recovery is possible, or 0 if not
 821  *
 822  */
 823 static int pkt_start_recovery(struct packet_data *pkt)
 824 {
 825         /*
 826          * FIXME. We need help from the file system to implement
 827          * recovery handling.
 828          */
 829         return 0;
 830 #if 0
 831         struct request *rq = pkt->rq;
 832         struct pktcdvd_device *pd = rq->rq_disk->private_data;
 833         struct block_device *pkt_bdev;
 834         struct super_block *sb = NULL;
 835         unsigned long old_block, new_block;
 836         sector_t new_sector;
 837
 838         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
 839         if (pkt_bdev) {
 840                 sb = get_super(pkt_bdev);
 841                 bdput(pkt_bdev);
 842         }
 843
 844         if (!sb)
 845                 return 0;
 846
 847         if (!sb->s_op || !sb->s_op->relocate_blocks)
 848                 goto out;
 849
 850         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
 851         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
 852                 goto out;
 853
 854         new_sector = new_block * (CD_FRAMESIZE >> 9);
 855         pkt->sector = new_sector;
 856
 857         pkt->bio->bi_sector = new_sector;
 858         pkt->bio->bi_next = NULL;
 859         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
 860         pkt->bio->bi_idx = 0;
 861
 862         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
 863         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
 864         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
 865         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
 866         BUG_ON(pkt->bio->bi_private != pkt);
 867
 868         drop_super(sb);
 869         return 1;
 870
 871 out:
 872         drop_super(sb);
 873         return 0;
 874 #endif
 875 }
 876
 877 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
 878 {
 879 #if PACKET_DEBUG > 1
 880         static const char *state_name[] = {
 881                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
 882         };
 883         enum packet_data_state old_state = pkt->state;
 884         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
 885                 state_name[old_state], state_name[state]);
 886 #endif
 887         pkt->state = state;
 888 }
 889
 890 /*
 891  * Scan the work queue to see if we can start a new packet.
 892  * returns non-zero if any work was done.
 893  */
 894 static int pkt_handle_queue(struct pktcdvd_device *pd)
 895 {
 896         struct packet_data *pkt, *p;
 897         struct bio *bio = NULL;
 898         sector_t zone = 0; /* Suppress gcc warning */
 899         struct pkt_rb_node *node, *first_node;
 900         struct rb_node *n;
 901
 902         VPRINTK("handle_queue\n");
 903
 904         atomic_set(&pd->scan_queue, 0);
 905
 906         if (list_empty(&pd->cdrw.pkt_free_list)) {
 907                 VPRINTK("handle_queue: no pkt\n");
 908                 return 0;
 909         }
 910
 911         /*
 912          * Try to find a zone we are not already working on.
 913          */
 914         spin_lock(&pd->lock);
 915         first_node = pkt_rbtree_find(pd, pd->current_sector);
 916         if (!first_node) {
 917                 n = rb_first(&pd->bio_queue);
 918                 if (n)
 919                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
 920         }
 921         node = first_node;
 922         while (node) {
 923                 bio = node->bio;
 924                 zone = ZONE(bio->bi_sector, pd);
 925                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
 926                         if (p->sector == zone) {
 927                                 bio = NULL;
 928                                 goto try_next_bio;
 929                         }
 930                 }
 931                 break;
 932 try_next_bio:
 933                 node = pkt_rbtree_next(node);
 934                 if (!node) {
 935                         n = rb_first(&pd->bio_queue);
 936                         if (n)
 937                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
 938                 }
 939                 if (node == first_node)
 940                         node = NULL;
 941         }
 942         spin_unlock(&pd->lock);
 943         if (!bio) {
 944                 VPRINTK("handle_queue: no bio\n");
 945                 return 0;
 946         }
 947
 948         pkt = pkt_get_packet_data(pd, zone);
 949
 950         pd->current_sector = zone + pd->settings.size;
 951         pkt->sector = zone;
 952         pkt->frames = pd->settings.size >> 2;
 953         pkt->write_size = 0;
 954
 955         /*
 956          * Scan work queue for bios in the same zone and link them
 957          * to this packet.
 958          */
 959         spin_lock(&pd->lock);
 960         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
 961         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
 962                 bio = node->bio;
 963                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
 964                         (unsigned long long)ZONE(bio->bi_sector, pd));
 965                 if (ZONE(bio->bi_sector, pd) != zone)
 966                         break;
 967                 pkt_rbtree_erase(pd, node);
 968                 spin_lock(&pkt->lock);
 969                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
 970                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
 971                 spin_unlock(&pkt->lock);
 972         }
 973         spin_unlock(&pd->lock);
 974
 975         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
 976         pkt_set_state(pkt, PACKET_WAITING_STATE);
 977         atomic_set(&pkt->run_sm, 1);
 978
 979         spin_lock(&pd->cdrw.active_list_lock);
 980         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
 981         spin_unlock(&pd->cdrw.active_list_lock);
 982
 983         return 1;
 984 }
 985
 986 /*
 987  * Assemble a bio to write one packet and queue the bio for processing
 988  * by the underlying block device.
 989  */
 990 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 991 {
 992         struct bio *bio;
 993         struct page *pages[PACKET_MAX_SIZE];
 994         int offsets[PACKET_MAX_SIZE];
 995         int f;
 996         int frames_write;
 997
 998         for (f = 0; f < pkt->frames; f++) {
 999                 pages[f] = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1000                 offsets[f] = (f * CD_FRAMESIZE) % PAGE_SIZE;
1001         }
1002
1003         /*
1004          * Fill-in pages[] and offsets[] with data from orig_bios.
1005          */
1006         frames_write = 0;
1007         spin_lock(&pkt->lock);
1008         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1009                 int segment = bio->bi_idx;
1010                 int src_offs = 0;
1011                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1012                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1013                 BUG_ON(first_frame < 0);
1014                 BUG_ON(first_frame + num_frames > pkt->frames);
1015                 for (f = first_frame; f < first_frame + num_frames; f++) {
1016                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1017
1018                         while (src_offs >= src_bvl->bv_len) {
1019                                 src_offs -= src_bvl->bv_len;
1020                                 segment++;
1021                                 BUG_ON(segment >= bio->bi_vcnt);
1022                                 src_bvl = bio_iovec_idx(bio, segment);
1023                         }
1024
1025                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1026                                 pages[f] = src_bvl->bv_page;
1027                                 offsets[f] = src_bvl->bv_offset + src_offs;
1028                         } else {
1029                                 pkt_copy_bio_data(bio, segment, src_offs,
1030                                                   pages[f], offsets[f]);
1031                         }
1032                         src_offs += CD_FRAMESIZE;
1033                         frames_write++;
1034                 }
1035         }
1036         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1037         spin_unlock(&pkt->lock);
1038
1039         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1040                 frames_write, (unsigned long long)pkt->sector);
1041         BUG_ON(frames_write != pkt->write_size);
1042
1043         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1044                 pkt_make_local_copy(pkt, pages, offsets);
1045                 pkt->cache_valid = 1;
1046         } else {
1047                 pkt->cache_valid = 0;
1048         }
1049
1050         /* Start the write request */
1051         bio_init(pkt->w_bio);
1052         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1053         pkt->w_bio->bi_sector = pkt->sector;
1054         pkt->w_bio->bi_bdev = pd->bdev;
1055         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1056         pkt->w_bio->bi_private = pkt;
1057         for (f = 0; f < pkt->frames; f++) {
1058                 if ((f + 1 < pkt->frames) && (pages[f + 1] == pages[f]) &&
1059                     (offsets[f + 1] = offsets[f] + CD_FRAMESIZE)) {
1060                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE * 2, offsets[f]))
1061                                 BUG();
1062                         f++;
1063                 } else {
1064                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE, offsets[f]))
1065                                 BUG();
1066                 }
1067         }
1068         VPRINTK("pktcdvd: vcnt=%d\n", pkt->w_bio->bi_vcnt);
1069
1070         atomic_set(&pkt->io_wait, 1);
1071         pkt->w_bio->bi_rw = WRITE;
1072         pkt_queue_bio(pd, pkt->w_bio);
1073 }
1074
1075 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1076 {
1077         struct bio *bio, *next;
1078
1079         if (!uptodate)
1080                 pkt->cache_valid = 0;
1081
1082         /* Finish all bios corresponding to this packet */
1083         bio = pkt->orig_bios;
1084         while (bio) {
1085                 next = bio->bi_next;
1086                 bio->bi_next = NULL;
1087                 bio_endio(bio, bio->bi_size, uptodate ? 0 : -EIO);
1088                 bio = next;
1089         }
1090         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1091 }
1092
1093 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1094 {
1095         int uptodate;
1096
1097         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1098
1099         for (;;) {
1100                 switch (pkt->state) {
1101                 case PACKET_WAITING_STATE:
1102                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1103                                 return;
1104
1105                         pkt->sleep_time = 0;
1106                         pkt_gather_data(pd, pkt);
1107                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1108                         break;
1109
1110                 case PACKET_READ_WAIT_STATE:
1111                         if (atomic_read(&pkt->io_wait) > 0)
1112                                 return;
1113
1114                         if (atomic_read(&pkt->io_errors) > 0) {
1115                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1116                         } else {
1117                                 pkt_start_write(pd, pkt);
1118                         }
1119                         break;
1120
1121                 case PACKET_WRITE_WAIT_STATE:
1122                         if (atomic_read(&pkt->io_wait) > 0)
1123                                 return;
1124
1125                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1126                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1127                         } else {
1128                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1129                         }
1130                         break;
1131
1132                 case PACKET_RECOVERY_STATE:
1133                         if (pkt_start_recovery(pkt)) {
1134                                 pkt_start_write(pd, pkt);
1135                         } else {
1136                                 VPRINTK("No recovery possible\n");
1137                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1138                         }
1139                         break;
1140
1141                 case PACKET_FINISHED_STATE:
1142                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1143                         pkt_finish_packet(pkt, uptodate);
1144                         return;
1145
1146                 default:
1147                         BUG();
1148                         break;
1149                 }
1150         }
1151 }
1152
1153 static void pkt_handle_packets(struct pktcdvd_device *pd)
1154 {
1155         struct packet_data *pkt, *next;
1156
1157         VPRINTK("pkt_handle_packets\n");
1158
1159         /*
1160          * Run state machine for active packets
1161          */
1162         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1163                 if (atomic_read(&pkt->run_sm) > 0) {
1164                         atomic_set(&pkt->run_sm, 0);
1165                         pkt_run_state_machine(pd, pkt);
1166                 }
1167         }
1168
1169         /*
1170          * Move no longer active packets to the free list
1171          */
1172         spin_lock(&pd->cdrw.active_list_lock);
1173         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1174                 if (pkt->state == PACKET_FINISHED_STATE) {
1175                         list_del(&pkt->list);
1176                         pkt_put_packet_data(pd, pkt);
1177                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1178                         atomic_set(&pd->scan_queue, 1);
1179                 }
1180         }
1181         spin_unlock(&pd->cdrw.active_list_lock);
1182 }
1183
1184 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1185 {
1186         struct packet_data *pkt;
1187         int i;
1188
1189         for (i = 0; i < PACKET_NUM_STATES; i++)
1190                 states[i] = 0;
1191
1192         spin_lock(&pd->cdrw.active_list_lock);
1193         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1194                 states[pkt->state]++;
1195         }
1196         spin_unlock(&pd->cdrw.active_list_lock);
1197 }
1198
1199 /*
1200  * kcdrwd is woken up when writes have been queued for one of our
1201  * registered devices
1202  */
1203 static int kcdrwd(void *foobar)
1204 {
1205         struct pktcdvd_device *pd = foobar;
1206         struct packet_data *pkt;
1207         long min_sleep_time, residue;
1208
1209         set_user_nice(current, -20);
1210
1211         for (;;) {
1212                 DECLARE_WAITQUEUE(wait, current);
1213
1214                 /*
1215                  * Wait until there is something to do
1216                  */
1217                 add_wait_queue(&pd->wqueue, &wait);
1218                 for (;;) {
1219                         set_current_state(TASK_INTERRUPTIBLE);
1220
1221                         /* Check if we need to run pkt_handle_queue */
1222                         if (atomic_read(&pd->scan_queue) > 0)
1223                                 goto work_to_do;
1224
1225                         /* Check if we need to run the state machine for some packet */
1226                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1227                                 if (atomic_read(&pkt->run_sm) > 0)
1228                                         goto work_to_do;
1229                         }
1230
1231                         /* Check if we need to process the iosched queues */
1232                         if (atomic_read(&pd->iosched.attention) != 0)
1233                                 goto work_to_do;
1234
1235                         /* Otherwise, go to sleep */
1236                         if (PACKET_DEBUG > 1) {
1237                                 int states[PACKET_NUM_STATES];
1238                                 pkt_count_states(pd, states);
1239                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1240                                         states[0], states[1], states[2], states[3],
1241                                         states[4], states[5]);
1242                         }
1243
1244                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1245                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1246                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1247                                         min_sleep_time = pkt->sleep_time;
1248                         }
1249
1250                         generic_unplug_device(bdev_get_queue(pd->bdev));
1251
1252                         VPRINTK("kcdrwd: sleeping\n");
1253                         residue = schedule_timeout(min_sleep_time);
1254                         VPRINTK("kcdrwd: wake up\n");
1255
1256                         /* make swsusp happy with our thread */
1257                         try_to_freeze();
1258
1259                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1260                                 if (!pkt->sleep_time)
1261                                         continue;
1262                                 pkt->sleep_time -= min_sleep_time - residue;
1263                                 if (pkt->sleep_time <= 0) {
1264                                         pkt->sleep_time = 0;
1265                                         atomic_inc(&pkt->run_sm);
1266                                 }
1267                         }
1268
1269                         if (signal_pending(current)) {
1270                                 flush_signals(current);
1271                         }
1272                         if (kthread_should_stop())
1273                                 break;
1274                 }
1275 work_to_do:
1276                 set_current_state(TASK_RUNNING);
1277                 remove_wait_queue(&pd->wqueue, &wait);
1278
1279                 if (kthread_should_stop())
1280                         break;
1281
1282                 /*
1283                  * if pkt_handle_queue returns true, we can queue
1284                  * another request.
1285                  */
1286                 while (pkt_handle_queue(pd))
1287                         ;
1288
1289                 /*
1290                  * Handle packet state machine
1291                  */
1292                 pkt_handle_packets(pd);
1293
1294                 /*
1295                  * Handle iosched queues
1296                  */
1297                 pkt_iosched_process_queue(pd);
1298         }
1299
1300         return 0;
1301 }
1302
1303 static void pkt_print_settings(struct pktcdvd_device *pd)
1304 {
1305         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1306         printk("%u blocks, ", pd->settings.size >> 2);
1307         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1308 }
1309
1310 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1311 {
1312         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1313
1314         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1315         cgc->cmd[2] = page_code | (page_control << 6);
1316         cgc->cmd[7] = cgc->buflen >> 8;
1317         cgc->cmd[8] = cgc->buflen & 0xff;
1318         cgc->data_direction = CGC_DATA_READ;
1319         return pkt_generic_packet(pd, cgc);
1320 }
1321
1322 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1323 {
1324         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1325         memset(cgc->buffer, 0, 2);
1326         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1327         cgc->cmd[1] = 0x10;             /* PF */
1328         cgc->cmd[7] = cgc->buflen >> 8;
1329         cgc->cmd[8] = cgc->buflen & 0xff;
1330         cgc->data_direction = CGC_DATA_WRITE;
1331         return pkt_generic_packet(pd, cgc);
1332 }
1333
1334 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1335 {
1336         struct packet_command cgc;
1337         int ret;
1338
1339         /* set up command and get the disc info */
1340         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1341         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1342         cgc.cmd[8] = cgc.buflen = 2;
1343         cgc.quiet = 1;
1344
1345         if ((ret = pkt_generic_packet(pd, &cgc)))
1346                 return ret;
1347
1348         /* not all drives have the same disc_info length, so requeue
1349          * packet with the length the drive tells us it can supply
1350          */
1351         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1352                      sizeof(di->disc_information_length);
1353
1354         if (cgc.buflen > sizeof(disc_information))
1355                 cgc.buflen = sizeof(disc_information);
1356
1357         cgc.cmd[8] = cgc.buflen;
1358         return pkt_generic_packet(pd, &cgc);
1359 }
1360
1361 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1362 {
1363         struct packet_command cgc;
1364         int ret;
1365
1366         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1367         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1368         cgc.cmd[1] = type & 3;
1369         cgc.cmd[4] = (track & 0xff00) >> 8;
1370         cgc.cmd[5] = track & 0xff;
1371         cgc.cmd[8] = 8;
1372         cgc.quiet = 1;
1373
1374         if ((ret = pkt_generic_packet(pd, &cgc)))
1375                 return ret;
1376
1377         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1378                      sizeof(ti->track_information_length);
1379
1380         if (cgc.buflen > sizeof(track_information))
1381                 cgc.buflen = sizeof(track_information);
1382
1383         cgc.cmd[8] = cgc.buflen;
1384         return pkt_generic_packet(pd, &cgc);
1385 }
1386
1387 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1388 {
1389         disc_information di;
1390         track_information ti;
1391         __u32 last_track;
1392         int ret = -1;
1393
1394         if ((ret = pkt_get_disc_info(pd, &di)))
1395                 return ret;
1396
1397         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1398         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1399                 return ret;
1400
1401         /* if this track is blank, try the previous. */
1402         if (ti.blank) {
1403                 last_track--;
1404                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1405                         return ret;
1406         }
1407
1408         /* if last recorded field is valid, return it. */
1409         if (ti.lra_v) {
1410                 *last_written = be32_to_cpu(ti.last_rec_address);
1411         } else {
1412                 /* make it up instead */
1413                 *last_written = be32_to_cpu(ti.track_start) +
1414                                 be32_to_cpu(ti.track_size);
1415                 if (ti.free_blocks)
1416                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1417         }
1418         return 0;
1419 }
1420
1421 /*
1422  * write mode select package based on pd->settings
1423  */
1424 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1425 {
1426         struct packet_command cgc;
1427         struct request_sense sense;
1428         write_param_page *wp;
1429         char buffer[128];
1430         int ret, size;
1431
1432         /* doesn't apply to DVD+RW or DVD-RAM */
1433         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1434                 return 0;
1435
1436         memset(buffer, 0, sizeof(buffer));
1437         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1438         cgc.sense = &sense;
1439         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1440                 pkt_dump_sense(&cgc);
1441                 return ret;
1442         }
1443
1444         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1445         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1446         if (size > sizeof(buffer))
1447                 size = sizeof(buffer);
1448
1449         /*
1450          * now get it all
1451          */
1452         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1453         cgc.sense = &sense;
1454         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1455                 pkt_dump_sense(&cgc);
1456                 return ret;
1457         }
1458
1459         /*
1460          * write page is offset header + block descriptor length
1461          */
1462         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1463
1464         wp->fp = pd->settings.fp;
1465         wp->track_mode = pd->settings.track_mode;
1466         wp->write_type = pd->settings.write_type;
1467         wp->data_block_type = pd->settings.block_mode;
1468
1469         wp->multi_session = 0;
1470
1471 #ifdef PACKET_USE_LS
1472         wp->link_size = 7;
1473         wp->ls_v = 1;
1474 #endif
1475
1476         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1477                 wp->session_format = 0;
1478                 wp->subhdr2 = 0x20;
1479         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1480                 wp->session_format = 0x20;
1481                 wp->subhdr2 = 8;
1482 #if 0
1483                 wp->mcn[0] = 0x80;
1484                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1485 #endif
1486         } else {
1487                 /*
1488                  * paranoia
1489                  */
1490                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1491                 return 1;
1492         }
1493         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1494
1495         cgc.buflen = cgc.cmd[8] = size;
1496         if ((ret = pkt_mode_select(pd, &cgc))) {
1497                 pkt_dump_sense(&cgc);
1498                 return ret;
1499         }
1500
1501         pkt_print_settings(pd);
1502         return 0;
1503 }
1504
1505 /*
1506  * 0 -- we can write to this track, 1 -- we can't
1507  */
1508 static int pkt_good_track(track_information *ti)
1509 {
1510         /*
1511          * only good for CD-RW at the moment, not DVD-RW
1512          */
1513
1514         /*
1515          * FIXME: only for FP
1516          */
1517         if (ti->fp == 0)
1518                 return 0;
1519
1520         /*
1521          * "good" settings as per Mt Fuji.
1522          */
1523         if (ti->rt == 0 && ti->blank == 0 && ti->packet == 1)
1524                 return 0;
1525
1526         if (ti->rt == 0 && ti->blank == 1 && ti->packet == 1)
1527                 return 0;
1528
1529         if (ti->rt == 1 && ti->blank == 0 && ti->packet == 1)
1530                 return 0;
1531
1532         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1533         return 1;
1534 }
1535
1536 /*
1537  * 0 -- we can write to this disc, 1 -- we can't
1538  */
1539 static int pkt_good_disc(struct pktcdvd_device *pd, disc_information *di)
1540 {
1541         switch (pd->mmc3_profile) {
1542                 case 0x0a: /* CD-RW */
1543                 case 0xffff: /* MMC3 not supported */
1544                         break;
1545                 case 0x1a: /* DVD+RW */
1546                 case 0x13: /* DVD-RW */
1547                 case 0x12: /* DVD-RAM */
1548                         return 0;
1549                 default:
1550                         printk("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1551                         return 1;
1552         }
1553
1554         /*
1555          * for disc type 0xff we should probably reserve a new track.
1556          * but i'm not sure, should we leave this to user apps? probably.
1557          */
1558         if (di->disc_type == 0xff) {
1559                 printk("pktcdvd: Unknown disc. No track?\n");
1560                 return 1;
1561         }
1562
1563         if (di->disc_type != 0x20 && di->disc_type != 0) {
1564                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1565                 return 1;
1566         }
1567
1568         if (di->erasable == 0) {
1569                 printk("pktcdvd: Disc not erasable\n");
1570                 return 1;
1571         }
1572
1573         if (di->border_status == PACKET_SESSION_RESERVED) {
1574                 printk("pktcdvd: Can't write to last track (reserved)\n");
1575                 return 1;
1576         }
1577
1578         return 0;
1579 }
1580
1581 static int pkt_probe_settings(struct pktcdvd_device *pd)
1582 {
1583         struct packet_command cgc;
1584         unsigned char buf[12];
1585         disc_information di;
1586         track_information ti;
1587         int ret, track;
1588
1589         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1590         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1591         cgc.cmd[8] = 8;
1592         ret = pkt_generic_packet(pd, &cgc);
1593         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1594
1595         memset(&di, 0, sizeof(disc_information));
1596         memset(&ti, 0, sizeof(track_information));
1597
1598         if ((ret = pkt_get_disc_info(pd, &di))) {
1599                 printk("failed get_disc\n");
1600                 return ret;
1601         }
1602
1603         if (pkt_good_disc(pd, &di))
1604                 return -ENXIO;
1605
1606         switch (pd->mmc3_profile) {
1607                 case 0x1a: /* DVD+RW */
1608                         printk("pktcdvd: inserted media is DVD+RW\n");
1609                         break;
1610                 case 0x13: /* DVD-RW */
1611                         printk("pktcdvd: inserted media is DVD-RW\n");
1612                         break;
1613                 case 0x12: /* DVD-RAM */
1614                         printk("pktcdvd: inserted media is DVD-RAM\n");
1615                         break;
1616                 default:
1617                         printk("pktcdvd: inserted media is CD-R%s\n", di.erasable ? "W" : "");
1618                         break;
1619         }
1620         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1621
1622         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1623         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1624                 printk("pktcdvd: failed get_track\n");
1625                 return ret;
1626         }
1627
1628         if (pkt_good_track(&ti)) {
1629                 printk("pktcdvd: can't write to this track\n");
1630                 return -ENXIO;
1631         }
1632
1633         /*
1634          * we keep packet size in 512 byte units, makes it easier to
1635          * deal with request calculations.
1636          */
1637         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1638         if (pd->settings.size == 0) {
1639                 printk("pktcdvd: detected zero packet size!\n");
1640                 return -ENXIO;
1641         }
1642         if (pd->settings.size > PACKET_MAX_SECTORS) {
1643                 printk("pktcdvd: packet size is too big\n");
1644                 return -ENXIO;
1645         }
1646         pd->settings.fp = ti.fp;
1647         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1648
1649         if (ti.nwa_v) {
1650                 pd->nwa = be32_to_cpu(ti.next_writable);
1651                 set_bit(PACKET_NWA_VALID, &pd->flags);
1652         }
1653
1654         /*
1655          * in theory we could use lra on -RW media as well and just zero
1656          * blocks that haven't been written yet, but in practice that
1657          * is just a no-go. we'll use that for -R, naturally.
1658          */
1659         if (ti.lra_v) {
1660                 pd->lra = be32_to_cpu(ti.last_rec_address);
1661                 set_bit(PACKET_LRA_VALID, &pd->flags);
1662         } else {
1663                 pd->lra = 0xffffffff;
1664                 set_bit(PACKET_LRA_VALID, &pd->flags);
1665         }
1666
1667         /*
1668          * fine for now
1669          */
1670         pd->settings.link_loss = 7;
1671         pd->settings.write_type = 0;    /* packet */
1672         pd->settings.track_mode = ti.track_mode;
1673
1674         /*
1675          * mode1 or mode2 disc
1676          */
1677         switch (ti.data_mode) {
1678                 case PACKET_MODE1:
1679                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1680                         break;
1681                 case PACKET_MODE2:
1682                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1683                         break;
1684                 default:
1685                         printk("pktcdvd: unknown data mode\n");
1686                         return 1;
1687         }
1688         return 0;
1689 }
1690
1691 /*
1692  * enable/disable write caching on drive
1693  */
1694 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1695 {
1696         struct packet_command cgc;
1697         struct request_sense sense;
1698         unsigned char buf[64];
1699         int ret;
1700
1701         memset(buf, 0, sizeof(buf));
1702         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1703         cgc.sense = &sense;
1704         cgc.buflen = pd->mode_offset + 12;
1705
1706         /*
1707          * caching mode page might not be there, so quiet this command
1708          */
1709         cgc.quiet = 1;
1710
1711         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1712                 return ret;
1713
1714         buf[pd->mode_offset + 10] |= (!!set << 2);
1715
1716         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1717         ret = pkt_mode_select(pd, &cgc);
1718         if (ret) {
1719                 printk("pktcdvd: write caching control failed\n");
1720                 pkt_dump_sense(&cgc);
1721         } else if (!ret && set)
1722                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1723         return ret;
1724 }
1725
1726 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1727 {
1728         struct packet_command cgc;
1729
1730         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1731         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1732         cgc.cmd[4] = lockflag ? 1 : 0;
1733         return pkt_generic_packet(pd, &cgc);
1734 }
1735
1736 /*
1737  * Returns drive maximum write speed
1738  */
1739 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1740 {
1741         struct packet_command cgc;
1742         struct request_sense sense;
1743         unsigned char buf[256+18];
1744         unsigned char *cap_buf;
1745         int ret, offset;
1746
1747         memset(buf, 0, sizeof(buf));
1748         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1749         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1750         cgc.sense = &sense;
1751
1752         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1753         if (ret) {
1754                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1755                              sizeof(struct mode_page_header);
1756                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1757                 if (ret) {
1758                         pkt_dump_sense(&cgc);
1759                         return ret;
1760                 }
1761         }
1762
1763         offset = 20;                        /* Obsoleted field, used by older drives */
1764         if (cap_buf[1] >= 28)
1765                 offset = 28;                /* Current write speed selected */
1766         if (cap_buf[1] >= 30) {
1767                 /* If the drive reports at least one "Logical Unit Write
1768                  * Speed Performance Descriptor Block", use the information
1769                  * in the first block. (contains the highest speed)
1770                  */
1771                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1772                 if (num_spdb > 0)
1773                         offset = 34;
1774         }
1775
1776         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1777         return 0;
1778 }
1779
1780 /* These tables from cdrecord - I don't have orange book */
1781 /* standard speed CD-RW (1-4x) */
1782 static char clv_to_speed[16] = {
1783         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1784            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1785 };
1786 /* high speed CD-RW (-10x) */
1787 static char hs_clv_to_speed[16] = {
1788         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1789            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1790 };
1791 /* ultra high speed CD-RW */
1792 static char us_clv_to_speed[16] = {
1793         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1794            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1795 };
1796
1797 /*
1798  * reads the maximum media speed from ATIP
1799  */
1800 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1801 {
1802         struct packet_command cgc;
1803         struct request_sense sense;
1804         unsigned char buf[64];
1805         unsigned int size, st, sp;
1806         int ret;
1807
1808         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1809         cgc.sense = &sense;
1810         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1811         cgc.cmd[1] = 2;
1812         cgc.cmd[2] = 4; /* READ ATIP */
1813         cgc.cmd[8] = 2;
1814         ret = pkt_generic_packet(pd, &cgc);
1815         if (ret) {
1816                 pkt_dump_sense(&cgc);
1817                 return ret;
1818         }
1819         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1820         if (size > sizeof(buf))
1821                 size = sizeof(buf);
1822
1823         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1824         cgc.sense = &sense;
1825         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1826         cgc.cmd[1] = 2;
1827         cgc.cmd[2] = 4;
1828         cgc.cmd[8] = size;
1829         ret = pkt_generic_packet(pd, &cgc);
1830         if (ret) {
1831                 pkt_dump_sense(&cgc);
1832                 return ret;
1833         }
1834
1835         if (!buf[6] & 0x40) {
1836                 printk("pktcdvd: Disc type is not CD-RW\n");
1837                 return 1;
1838         }
1839         if (!buf[6] & 0x4) {
1840                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1841                 return 1;
1842         }
1843
1844         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1845
1846         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1847
1848         /* Info from cdrecord */
1849         switch (st) {
1850                 case 0: /* standard speed */
1851                         *speed = clv_to_speed[sp];
1852                         break;
1853                 case 1: /* high speed */
1854                         *speed = hs_clv_to_speed[sp];
1855                         break;
1856                 case 2: /* ultra high speed */
1857                         *speed = us_clv_to_speed[sp];
1858                         break;
1859                 default:
1860                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1861                         return 1;
1862         }
1863         if (*speed) {
1864                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1865                 return 0;
1866         } else {
1867                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1868                 return 1;
1869         }
1870 }
1871
1872 static int pkt_perform_opc(struct pktcdvd_device *pd)
1873 {
1874         struct packet_command cgc;
1875         struct request_sense sense;
1876         int ret;
1877
1878         VPRINTK("pktcdvd: Performing OPC\n");
1879
1880         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1881         cgc.sense = &sense;
1882         cgc.timeout = 60*HZ;
1883         cgc.cmd[0] = GPCMD_SEND_OPC;
1884         cgc.cmd[1] = 1;
1885         if ((ret = pkt_generic_packet(pd, &cgc)))
1886                 pkt_dump_sense(&cgc);
1887         return ret;
1888 }
1889
1890 static int pkt_open_write(struct pktcdvd_device *pd)
1891 {
1892         int ret;
1893         unsigned int write_speed, media_write_speed, read_speed;
1894
1895         if ((ret = pkt_probe_settings(pd))) {
1896                 DPRINTK("pktcdvd: %s failed probe\n", pd->name);
1897                 return -EIO;
1898         }
1899
1900         if ((ret = pkt_set_write_settings(pd))) {
1901                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1902                 return -EIO;
1903         }
1904
1905         pkt_write_caching(pd, USE_WCACHING);
1906
1907         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1908                 write_speed = 16 * 177;
1909         switch (pd->mmc3_profile) {
1910                 case 0x13: /* DVD-RW */
1911                 case 0x1a: /* DVD+RW */
1912                 case 0x12: /* DVD-RAM */
1913                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1914                         break;
1915                 default:
1916                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1917                                 media_write_speed = 16;
1918                         write_speed = min(write_speed, media_write_speed * 177);
1919                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1920                         break;
1921         }
1922         read_speed = write_speed;
1923
1924         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1925                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1926                 return -EIO;
1927         }
1928         pd->write_speed = write_speed;
1929         pd->read_speed = read_speed;
1930
1931         if ((ret = pkt_perform_opc(pd))) {
1932                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1933         }
1934
1935         return 0;
1936 }
1937
1938 /*
1939  * called at open time.
1940  */
1941 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1942 {
1943         int ret;
1944         long lba;
1945         request_queue_t *q;
1946
1947         /*
1948          * We need to re-open the cdrom device without O_NONBLOCK to be able
1949          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1950          * so bdget() can't fail.
1951          */
1952         bdget(pd->bdev->bd_dev);
1953         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1954                 goto out;
1955
1956         if ((ret = bd_claim(pd->bdev, pd)))
1957                 goto out_putdev;
1958
1959         if ((ret = pkt_get_last_written(pd, &lba))) {
1960                 printk("pktcdvd: pkt_get_last_written failed\n");
1961                 goto out_unclaim;
1962         }
1963
1964         set_capacity(pd->disk, lba << 2);
1965         set_capacity(pd->bdev->bd_disk, lba << 2);
1966         bd_set_size(pd->bdev, (loff_t)lba << 11);
1967
1968         q = bdev_get_queue(pd->bdev);
1969         if (write) {
1970                 if ((ret = pkt_open_write(pd)))
1971                         goto out_unclaim;
1972                 /*
1973                  * Some CDRW drives can not handle writes larger than one packet,
1974                  * even if the size is a multiple of the packet size.
1975                  */
1976                 spin_lock_irq(q->queue_lock);
1977                 blk_queue_max_sectors(q, pd->settings.size);
1978                 spin_unlock_irq(q->queue_lock);
1979                 set_bit(PACKET_WRITABLE, &pd->flags);
1980         } else {
1981                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1982                 clear_bit(PACKET_WRITABLE, &pd->flags);
1983         }
1984
1985         if ((ret = pkt_set_segment_merging(pd, q)))
1986                 goto out_unclaim;
1987
1988         if (write)
1989                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1990
1991         return 0;
1992
1993 out_unclaim:
1994         bd_release(pd->bdev);
1995 out_putdev:
1996         blkdev_put(pd->bdev);
1997 out:
1998         return ret;
1999 }
2000
2001 /*
2002  * called when the device is closed. makes sure that the device flushes
2003  * the internal cache before we close.
2004  */
2005 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2006 {
2007         if (flush && pkt_flush_cache(pd))
2008                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
2009
2010         pkt_lock_door(pd, 0);
2011
2012         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2013         bd_release(pd->bdev);
2014         blkdev_put(pd->bdev);
2015 }
2016
2017 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2018 {
2019         if (dev_minor >= MAX_WRITERS)
2020                 return NULL;
2021         return pkt_devs[dev_minor];
2022 }
2023
2024 static int pkt_open(struct inode *inode, struct file *file)
2025 {
2026         struct pktcdvd_device *pd = NULL;
2027         int ret;
2028
2029         VPRINTK("pktcdvd: entering open\n");
2030
2031         down(&ctl_mutex);
2032         pd = pkt_find_dev_from_minor(iminor(inode));
2033         if (!pd) {
2034                 ret = -ENODEV;
2035                 goto out;
2036         }
2037         BUG_ON(pd->refcnt < 0);
2038
2039         pd->refcnt++;
2040         if (pd->refcnt > 1) {
2041                 if ((file->f_mode & FMODE_WRITE) &&
2042                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2043                         ret = -EBUSY;
2044                         goto out_dec;
2045                 }
2046         } else {
2047                 if (pkt_open_dev(pd, file->f_mode & FMODE_WRITE)) {
2048                         ret = -EIO;
2049                         goto out_dec;
2050                 }
2051                 /*
2052                  * needed here as well, since ext2 (among others) may change
2053                  * the blocksize at mount time
2054                  */
2055                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2056         }
2057
2058         up(&ctl_mutex);
2059         return 0;
2060
2061 out_dec:
2062         pd->refcnt--;
2063 out:
2064         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2065         up(&ctl_mutex);
2066         return ret;
2067 }
2068
2069 static int pkt_close(struct inode *inode, struct file *file)
2070 {
2071         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2072         int ret = 0;
2073
2074         down(&ctl_mutex);
2075         pd->refcnt--;
2076         BUG_ON(pd->refcnt < 0);
2077         if (pd->refcnt == 0) {
2078                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2079                 pkt_release_dev(pd, flush);
2080         }
2081         up(&ctl_mutex);
2082         return ret;
2083 }
2084
2085
2086 static void *psd_pool_alloc(gfp_t gfp_mask, void *data)
2087 {
2088         return kmalloc(sizeof(struct packet_stacked_data), gfp_mask);
2089 }
2090
2091 static void psd_pool_free(void *ptr, void *data)
2092 {
2093         kfree(ptr);
2094 }
2095
2096 static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int err)
2097 {
2098         struct packet_stacked_data *psd = bio->bi_private;
2099         struct pktcdvd_device *pd = psd->pd;
2100
2101         if (bio->bi_size)
2102                 return 1;
2103
2104         bio_put(bio);
2105         bio_endio(psd->bio, psd->bio->bi_size, err);
2106         mempool_free(psd, psd_pool);
2107         pkt_bio_finished(pd);
2108         return 0;
2109 }
2110
2111 static int pkt_make_request(request_queue_t *q, struct bio *bio)
2112 {
2113         struct pktcdvd_device *pd;
2114         char b[BDEVNAME_SIZE];
2115         sector_t zone;
2116         struct packet_data *pkt;
2117         int was_empty, blocked_bio;
2118         struct pkt_rb_node *node;
2119
2120         pd = q->queuedata;
2121         if (!pd) {
2122                 printk("pktcdvd: %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2123                 goto end_io;
2124         }
2125
2126         /*
2127          * Clone READ bios so we can have our own bi_end_io callback.
2128          */
2129         if (bio_data_dir(bio) == READ) {
2130                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2131                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2132
2133                 psd->pd = pd;
2134                 psd->bio = bio;
2135                 cloned_bio->bi_bdev = pd->bdev;
2136                 cloned_bio->bi_private = psd;
2137                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2138                 pd->stats.secs_r += bio->bi_size >> 9;
2139                 pkt_queue_bio(pd, cloned_bio);
2140                 return 0;
2141         }
2142
2143         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2144                 printk("pktcdvd: WRITE for ro device %s (%llu)\n",
2145                         pd->name, (unsigned long long)bio->bi_sector);
2146                 goto end_io;
2147         }
2148
2149         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2150                 printk("pktcdvd: wrong bio size\n");
2151                 goto end_io;
2152         }
2153
2154         blk_queue_bounce(q, &bio);
2155
2156         zone = ZONE(bio->bi_sector, pd);
2157         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2158                 (unsigned long long)bio->bi_sector,
2159                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2160
2161         /* Check if we have to split the bio */
2162         {
2163                 struct bio_pair *bp;
2164                 sector_t last_zone;
2165                 int first_sectors;
2166
2167                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2168                 if (last_zone != zone) {
2169                         BUG_ON(last_zone != zone + pd->settings.size);
2170                         first_sectors = last_zone - bio->bi_sector;
2171                         bp = bio_split(bio, bio_split_pool, first_sectors);
2172                         BUG_ON(!bp);
2173                         pkt_make_request(q, &bp->bio1);
2174                         pkt_make_request(q, &bp->bio2);
2175                         bio_pair_release(bp);
2176                         return 0;
2177                 }
2178         }
2179
2180         /*
2181          * If we find a matching packet in state WAITING or READ_WAIT, we can
2182          * just append this bio to that packet.
2183          */
2184         spin_lock(&pd->cdrw.active_list_lock);
2185         blocked_bio = 0;
2186         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2187                 if (pkt->sector == zone) {
2188                         spin_lock(&pkt->lock);
2189                         if ((pkt->state == PACKET_WAITING_STATE) ||
2190                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2191                                 pkt_add_list_last(bio, &pkt->orig_bios,
2192                                                   &pkt->orig_bios_tail);
2193                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2194                                 if ((pkt->write_size >= pkt->frames) &&
2195                                     (pkt->state == PACKET_WAITING_STATE)) {
2196                                         atomic_inc(&pkt->run_sm);
2197                                         wake_up(&pd->wqueue);
2198                                 }
2199                                 spin_unlock(&pkt->lock);
2200                                 spin_unlock(&pd->cdrw.active_list_lock);
2201                                 return 0;
2202                         } else {
2203                                 blocked_bio = 1;
2204                         }
2205                         spin_unlock(&pkt->lock);
2206                 }
2207         }
2208         spin_unlock(&pd->cdrw.active_list_lock);
2209
2210         /*
2211          * No matching packet found. Store the bio in the work queue.
2212          */
2213         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2214         node->bio = bio;
2215         spin_lock(&pd->lock);
2216         BUG_ON(pd->bio_queue_size < 0);
2217         was_empty = (pd->bio_queue_size == 0);
2218         pkt_rbtree_insert(pd, node);
2219         spin_unlock(&pd->lock);
2220
2221         /*
2222          * Wake up the worker thread.
2223          */
2224         atomic_set(&pd->scan_queue, 1);
2225         if (was_empty) {
2226                 /* This wake_up is required for correct operation */
2227                 wake_up(&pd->wqueue);
2228         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2229                 /*
2230                  * This wake up is not required for correct operation,
2231                  * but improves performance in some cases.
2232                  */
2233                 wake_up(&pd->wqueue);
2234         }
2235         return 0;
2236 end_io:
2237         bio_io_error(bio, bio->bi_size);
2238         return 0;
2239 }
2240
2241
2242
2243 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2244 {
2245         struct pktcdvd_device *pd = q->queuedata;
2246         sector_t zone = ZONE(bio->bi_sector, pd);
2247         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2248         int remaining = (pd->settings.size << 9) - used;
2249         int remaining2;
2250
2251         /*
2252          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2253          * boundary, pkt_make_request() will split the bio.
2254          */
2255         remaining2 = PAGE_SIZE - bio->bi_size;
2256         remaining = max(remaining, remaining2);
2257
2258         BUG_ON(remaining < 0);
2259         return remaining;
2260 }
2261
2262 static void pkt_init_queue(struct pktcdvd_device *pd)
2263 {
2264         request_queue_t *q = pd->disk->queue;
2265
2266         blk_queue_make_request(q, pkt_make_request);
2267         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2268         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2269         blk_queue_merge_bvec(q, pkt_merge_bvec);
2270         q->queuedata = pd;
2271 }
2272
2273 static int pkt_seq_show(struct seq_file *m, void *p)
2274 {
2275         struct pktcdvd_device *pd = m->private;
2276         char *msg;
2277         char bdev_buf[BDEVNAME_SIZE];
2278         int states[PACKET_NUM_STATES];
2279
2280         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2281                    bdevname(pd->bdev, bdev_buf));
2282
2283         seq_printf(m, "\nSettings:\n");
2284         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2285
2286         if (pd->settings.write_type == 0)
2287                 msg = "Packet";
2288         else
2289                 msg = "Unknown";
2290         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2291
2292         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2293         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2294
2295         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2296
2297         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2298                 msg = "Mode 1";
2299         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2300                 msg = "Mode 2";
2301         else
2302                 msg = "Unknown";
2303         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2304
2305         seq_printf(m, "\nStatistics:\n");
2306         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2307         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2308         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2309         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2310         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2311
2312         seq_printf(m, "\nMisc:\n");
2313         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2314         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2315         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2316         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2317         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2318         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2319
2320         seq_printf(m, "\nQueue state:\n");
2321         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2322         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2323         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2324
2325         pkt_count_states(pd, states);
2326         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2327                    states[0], states[1], states[2], states[3], states[4], states[5]);
2328
2329         return 0;
2330 }
2331
2332 static int pkt_seq_open(struct inode *inode, struct file *file)
2333 {
2334         return single_open(file, pkt_seq_show, PDE(inode)->data);
2335 }
2336
2337 static struct file_operations pkt_proc_fops = {
2338         .open   = pkt_seq_open,
2339         .read   = seq_read,
2340         .llseek = seq_lseek,
2341         .release = single_release
2342 };
2343
2344 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2345 {
2346         int i;
2347         int ret = 0;
2348         char b[BDEVNAME_SIZE];
2349         struct proc_dir_entry *proc;
2350         struct block_device *bdev;
2351
2352         if (pd->pkt_dev == dev) {
2353                 printk("pktcdvd: Recursive setup not allowed\n");
2354                 return -EBUSY;
2355         }
2356         for (i = 0; i < MAX_WRITERS; i++) {
2357                 struct pktcdvd_device *pd2 = pkt_devs[i];
2358                 if (!pd2)
2359                         continue;
2360                 if (pd2->bdev->bd_dev == dev) {
2361                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2362                         return -EBUSY;
2363                 }
2364                 if (pd2->pkt_dev == dev) {
2365                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2366                         return -EBUSY;
2367                 }
2368         }
2369
2370         bdev = bdget(dev);
2371         if (!bdev)
2372                 return -ENOMEM;
2373         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2374         if (ret)
2375                 return ret;
2376
2377         /* This is safe, since we have a reference from open(). */
2378         __module_get(THIS_MODULE);
2379
2380         if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2381                 printk("pktcdvd: not enough memory for buffers\n");
2382                 ret = -ENOMEM;
2383                 goto out_mem;
2384         }
2385
2386         pd->bdev = bdev;
2387         set_blocksize(bdev, CD_FRAMESIZE);
2388
2389         pkt_init_queue(pd);
2390
2391         atomic_set(&pd->cdrw.pending_bios, 0);
2392         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2393         if (IS_ERR(pd->cdrw.thread)) {
2394                 printk("pktcdvd: can't start kernel thread\n");
2395                 ret = -ENOMEM;
2396                 goto out_thread;
2397         }
2398
2399         proc = create_proc_entry(pd->name, 0, pkt_proc);
2400         if (proc) {
2401                 proc->data = pd;
2402                 proc->proc_fops = &pkt_proc_fops;
2403         }
2404         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2405         return 0;
2406
2407 out_thread:
2408         pkt_shrink_pktlist(pd);
2409 out_mem:
2410         blkdev_put(bdev);
2411         /* This is safe: open() is still holding a reference. */
2412         module_put(THIS_MODULE);
2413         return ret;
2414 }
2415
2416 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2417 {
2418         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2419
2420         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2421
2422         switch (cmd) {
2423         /*
2424          * forward selected CDROM ioctls to CD-ROM, for UDF
2425          */
2426         case CDROMMULTISESSION:
2427         case CDROMREADTOCENTRY:
2428         case CDROM_LAST_WRITTEN:
2429         case CDROM_SEND_PACKET:
2430         case SCSI_IOCTL_SEND_COMMAND:
2431                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2432
2433         case CDROMEJECT:
2434                 /*
2435                  * The door gets locked when the device is opened, so we
2436                  * have to unlock it or else the eject command fails.
2437                  */
2438                 pkt_lock_door(pd, 0);
2439                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2440
2441         default:
2442                 printk("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2443                 return -ENOTTY;
2444         }
2445
2446         return 0;
2447 }
2448
2449 static int pkt_media_changed(struct gendisk *disk)
2450 {
2451         struct pktcdvd_device *pd = disk->private_data;
2452         struct gendisk *attached_disk;
2453
2454         if (!pd)
2455                 return 0;
2456         if (!pd->bdev)
2457                 return 0;
2458         attached_disk = pd->bdev->bd_disk;
2459         if (!attached_disk)
2460                 return 0;
2461         return attached_disk->fops->media_changed(attached_disk);
2462 }
2463
2464 static struct block_device_operations pktcdvd_ops = {
2465         .owner =                THIS_MODULE,
2466         .open =                 pkt_open,
2467         .release =              pkt_close,
2468         .ioctl =                pkt_ioctl,
2469         .media_changed =        pkt_media_changed,
2470 };
2471
2472 /*
2473  * Set up mapping from pktcdvd device to CD-ROM device.
2474  */
2475 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2476 {
2477         int idx;
2478         int ret = -ENOMEM;
2479         struct pktcdvd_device *pd;
2480         struct gendisk *disk;
2481         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2482
2483         for (idx = 0; idx < MAX_WRITERS; idx++)
2484                 if (!pkt_devs[idx])
2485                         break;
2486         if (idx == MAX_WRITERS) {
2487                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2488                 return -EBUSY;
2489         }
2490
2491         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2492         if (!pd)
2493                 return ret;
2494
2495         pd->rb_pool = mempool_create(PKT_RB_POOL_SIZE, pkt_rb_alloc, pkt_rb_free, NULL);
2496         if (!pd->rb_pool)
2497                 goto out_mem;
2498
2499         disk = alloc_disk(1);
2500         if (!disk)
2501                 goto out_mem;
2502         pd->disk = disk;
2503
2504         spin_lock_init(&pd->lock);
2505         spin_lock_init(&pd->iosched.lock);
2506         sprintf(pd->name, "pktcdvd%d", idx);
2507         init_waitqueue_head(&pd->wqueue);
2508         pd->bio_queue = RB_ROOT;
2509
2510         disk->major = pkt_major;
2511         disk->first_minor = idx;
2512         disk->fops = &pktcdvd_ops;
2513         disk->flags = GENHD_FL_REMOVABLE;
2514         sprintf(disk->disk_name, "pktcdvd%d", idx);
2515         disk->private_data = pd;
2516         disk->queue = blk_alloc_queue(GFP_KERNEL);
2517         if (!disk->queue)
2518                 goto out_mem2;
2519
2520         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2521         ret = pkt_new_dev(pd, dev);
2522         if (ret)
2523                 goto out_new_dev;
2524
2525         add_disk(disk);
2526         pkt_devs[idx] = pd;
2527         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2528         return 0;
2529
2530 out_new_dev:
2531         blk_put_queue(disk->queue);
2532 out_mem2:
2533         put_disk(disk);
2534 out_mem:
2535         if (pd->rb_pool)
2536                 mempool_destroy(pd->rb_pool);
2537         kfree(pd);
2538         return ret;
2539 }
2540
2541 /*
2542  * Tear down mapping from pktcdvd device to CD-ROM device.
2543  */
2544 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2545 {
2546         struct pktcdvd_device *pd;
2547         int idx;
2548         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2549
2550         for (idx = 0; idx < MAX_WRITERS; idx++) {
2551                 pd = pkt_devs[idx];
2552                 if (pd && (pd->pkt_dev == pkt_dev))
2553                         break;
2554         }
2555         if (idx == MAX_WRITERS) {
2556                 DPRINTK("pktcdvd: dev not setup\n");
2557                 return -ENXIO;
2558         }
2559
2560         if (pd->refcnt > 0)
2561                 return -EBUSY;
2562
2563         if (!IS_ERR(pd->cdrw.thread))
2564                 kthread_stop(pd->cdrw.thread);
2565
2566         blkdev_put(pd->bdev);
2567
2568         pkt_shrink_pktlist(pd);
2569
2570         remove_proc_entry(pd->name, pkt_proc);
2571         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2572
2573         del_gendisk(pd->disk);
2574         blk_put_queue(pd->disk->queue);
2575         put_disk(pd->disk);
2576
2577         pkt_devs[idx] = NULL;
2578         mempool_destroy(pd->rb_pool);
2579         kfree(pd);
2580
2581         /* This is safe: open() is still holding a reference. */
2582         module_put(THIS_MODULE);
2583         return 0;
2584 }
2585
2586 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2587 {
2588         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2589         if (pd) {
2590                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2591                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2592         } else {
2593                 ctrl_cmd->dev = 0;
2594                 ctrl_cmd->pkt_dev = 0;
2595         }
2596         ctrl_cmd->num_devices = MAX_WRITERS;
2597 }
2598
2599 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2600 {
2601         void __user *argp = (void __user *)arg;
2602         struct pkt_ctrl_command ctrl_cmd;
2603         int ret = 0;
2604
2605         if (cmd != PACKET_CTRL_CMD)
2606                 return -ENOTTY;
2607
2608         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2609                 return -EFAULT;
2610
2611         switch (ctrl_cmd.command) {
2612         case PKT_CTRL_CMD_SETUP:
2613                 if (!capable(CAP_SYS_ADMIN))
2614                         return -EPERM;
2615                 down(&ctl_mutex);
2616                 ret = pkt_setup_dev(&ctrl_cmd);
2617                 up(&ctl_mutex);
2618                 break;
2619         case PKT_CTRL_CMD_TEARDOWN:
2620                 if (!capable(CAP_SYS_ADMIN))
2621                         return -EPERM;
2622                 down(&ctl_mutex);
2623                 ret = pkt_remove_dev(&ctrl_cmd);
2624                 up(&ctl_mutex);
2625                 break;
2626         case PKT_CTRL_CMD_STATUS:
2627                 down(&ctl_mutex);
2628                 pkt_get_status(&ctrl_cmd);
2629                 up(&ctl_mutex);
2630                 break;
2631         default:
2632                 return -ENOTTY;
2633         }
2634
2635         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2636                 return -EFAULT;
2637         return ret;
2638 }
2639
2640
2641 static struct file_operations pkt_ctl_fops = {
2642         .ioctl   = pkt_ctl_ioctl,
2643         .owner   = THIS_MODULE,
2644 };
2645
2646 static struct miscdevice pkt_misc = {
2647         .minor          = MISC_DYNAMIC_MINOR,
2648         .name           = "pktcdvd",
2649         .devfs_name     = "pktcdvd/control",
2650         .fops           = &pkt_ctl_fops
2651 };
2652
2653 static int __init pkt_init(void)
2654 {
2655         int ret;
2656
2657         psd_pool = mempool_create(PSD_POOL_SIZE, psd_pool_alloc, psd_pool_free, NULL);
2658         if (!psd_pool)
2659                 return -ENOMEM;
2660
2661         ret = register_blkdev(pkt_major, "pktcdvd");
2662         if (ret < 0) {
2663                 printk("pktcdvd: Unable to register block device\n");
2664                 goto out2;
2665         }
2666         if (!pkt_major)
2667                 pkt_major = ret;
2668
2669         ret = misc_register(&pkt_misc);
2670         if (ret) {
2671                 printk("pktcdvd: Unable to register misc device\n");
2672                 goto out;
2673         }
2674
2675         init_MUTEX(&ctl_mutex);
2676
2677         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2678
2679         return 0;
2680
2681 out:
2682         unregister_blkdev(pkt_major, "pktcdvd");
2683 out2:
2684         mempool_destroy(psd_pool);
2685         return ret;
2686 }
2687
2688 static void __exit pkt_exit(void)
2689 {
2690         remove_proc_entry("pktcdvd", proc_root_driver);
2691         misc_deregister(&pkt_misc);
2692         unregister_blkdev(pkt_major, "pktcdvd");
2693         mempool_destroy(psd_pool);
2694 }
2695
2696 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2697 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2698 MODULE_LICENSE("GPL");
2699
2700 module_init(pkt_init);
2701 module_exit(pkt_exit);