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 #define VERSION_CODE    "v0.2.0a 2004-07-14 Jens Axboe (axboe@suse.de) and petero2@telia.com"
  47
  48 #include <linux/pktcdvd.h>
  49 #include <linux/config.h>
  50 #include <linux/module.h>
  51 #include <linux/types.h>
  52 #include <linux/kernel.h>
  53 #include <linux/kthread.h>
  54 #include <linux/errno.h>
  55 #include <linux/spinlock.h>
  56 #include <linux/file.h>
  57 #include <linux/proc_fs.h>
  58 #include <linux/seq_file.h>
  59 #include <linux/miscdevice.h>
  60 #include <linux/suspend.h>
  61 #include <scsi/scsi_cmnd.h>
  62 #include <scsi/scsi_ioctl.h>
  63
  64 #include <asm/uaccess.h>
  65
  66 #if PACKET_DEBUG
  67 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  68 #else
  69 #define DPRINTK(fmt, args...)
  70 #endif
  71
  72 #if PACKET_DEBUG > 1
  73 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  74 #else
  75 #define VPRINTK(fmt, args...)
  76 #endif
  77
  78 #define MAX_SPEED 0xffff
  79
  80 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  81
  82 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  83 static struct proc_dir_entry *pkt_proc;
  84 static int pkt_major;
  85 static struct semaphore ctl_mutex;      /* Serialize open/close/setup/teardown */
  86 static mempool_t *psd_pool;
  87
  88
  89 static void pkt_bio_finished(struct pktcdvd_device *pd)
  90 {
  91         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
  92         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
  93                 VPRINTK("pktcdvd: queue empty\n");
  94                 atomic_set(&pd->iosched.attention, 1);
  95                 wake_up(&pd->wqueue);
  96         }
  97 }
  98
  99 static void pkt_bio_destructor(struct bio *bio)
 100 {
 101         kfree(bio->bi_io_vec);
 102         kfree(bio);
 103 }
 104
 105 static struct bio *pkt_bio_alloc(int nr_iovecs)
 106 {
 107         struct bio_vec *bvl = NULL;
 108         struct bio *bio;
 109
 110         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
 111         if (!bio)
 112                 goto no_bio;
 113         bio_init(bio);
 114
 115         bvl = kmalloc(nr_iovecs * sizeof(struct bio_vec), GFP_KERNEL);
 116         if (!bvl)
 117                 goto no_bvl;
 118         memset(bvl, 0, nr_iovecs * sizeof(struct bio_vec));
 119
 120         bio->bi_max_vecs = nr_iovecs;
 121         bio->bi_io_vec = bvl;
 122         bio->bi_destructor = pkt_bio_destructor;
 123
 124         return bio;
 125
 126  no_bvl:
 127         kfree(bio);
 128  no_bio:
 129         return NULL;
 130 }
 131
 132 /*
 133  * Allocate a packet_data struct
 134  */
 135 static struct packet_data *pkt_alloc_packet_data(void)
 136 {
 137         int i;
 138         struct packet_data *pkt;
 139
 140         pkt = kmalloc(sizeof(struct packet_data), GFP_KERNEL);
 141         if (!pkt)
 142                 goto no_pkt;
 143         memset(pkt, 0, sizeof(struct packet_data));
 144
 145         pkt->w_bio = pkt_bio_alloc(PACKET_MAX_SIZE);
 146         if (!pkt->w_bio)
 147                 goto no_bio;
 148
 149         for (i = 0; i < PAGES_PER_PACKET; i++) {
 150                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 151                 if (!pkt->pages[i])
 152                         goto no_page;
 153         }
 154
 155         spin_lock_init(&pkt->lock);
 156
 157         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 158                 struct bio *bio = pkt_bio_alloc(1);
 159                 if (!bio)
 160                         goto no_rd_bio;
 161                 pkt->r_bios[i] = bio;
 162         }
 163
 164         return pkt;
 165
 166 no_rd_bio:
 167         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 168                 struct bio *bio = pkt->r_bios[i];
 169                 if (bio)
 170                         bio_put(bio);
 171         }
 172
 173 no_page:
 174         for (i = 0; i < PAGES_PER_PACKET; i++)
 175                 if (pkt->pages[i])
 176                         __free_page(pkt->pages[i]);
 177         bio_put(pkt->w_bio);
 178 no_bio:
 179         kfree(pkt);
 180 no_pkt:
 181         return NULL;
 182 }
 183
 184 /*
 185  * Free a packet_data struct
 186  */
 187 static void pkt_free_packet_data(struct packet_data *pkt)
 188 {
 189         int i;
 190
 191         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 192                 struct bio *bio = pkt->r_bios[i];
 193                 if (bio)
 194                         bio_put(bio);
 195         }
 196         for (i = 0; i < PAGES_PER_PACKET; i++)
 197                 __free_page(pkt->pages[i]);
 198         bio_put(pkt->w_bio);
 199         kfree(pkt);
 200 }
 201
 202 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 203 {
 204         struct packet_data *pkt, *next;
 205
 206         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 207
 208         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 209                 pkt_free_packet_data(pkt);
 210         }
 211 }
 212
 213 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 214 {
 215         struct packet_data *pkt;
 216
 217         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 218         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
 219         spin_lock_init(&pd->cdrw.active_list_lock);
 220         while (nr_packets > 0) {
 221                 pkt = pkt_alloc_packet_data();
 222                 if (!pkt) {
 223                         pkt_shrink_pktlist(pd);
 224                         return 0;
 225                 }
 226                 pkt->id = nr_packets;
 227                 pkt->pd = pd;
 228                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 229                 nr_packets--;
 230         }
 231         return 1;
 232 }
 233
 234 static void *pkt_rb_alloc(unsigned int __nocast gfp_mask, void *data)
 235 {
 236         return kmalloc(sizeof(struct pkt_rb_node), gfp_mask);
 237 }
 238
 239 static void pkt_rb_free(void *ptr, void *data)
 240 {
 241         kfree(ptr);
 242 }
 243
 244 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 245 {
 246         struct rb_node *n = rb_next(&node->rb_node);
 247         if (!n)
 248                 return NULL;
 249         return rb_entry(n, struct pkt_rb_node, rb_node);
 250 }
 251
 252 static inline void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 253 {
 254         rb_erase(&node->rb_node, &pd->bio_queue);
 255         mempool_free(node, pd->rb_pool);
 256         pd->bio_queue_size--;
 257         BUG_ON(pd->bio_queue_size < 0);
 258 }
 259
 260 /*
 261  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 262  */
 263 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 264 {
 265         struct rb_node *n = pd->bio_queue.rb_node;
 266         struct rb_node *next;
 267         struct pkt_rb_node *tmp;
 268
 269         if (!n) {
 270                 BUG_ON(pd->bio_queue_size > 0);
 271                 return NULL;
 272         }
 273
 274         for (;;) {
 275                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 276                 if (s <= tmp->bio->bi_sector)
 277                         next = n->rb_left;
 278                 else
 279                         next = n->rb_right;
 280                 if (!next)
 281                         break;
 282                 n = next;
 283         }
 284
 285         if (s > tmp->bio->bi_sector) {
 286                 tmp = pkt_rbtree_next(tmp);
 287                 if (!tmp)
 288                         return NULL;
 289         }
 290         BUG_ON(s > tmp->bio->bi_sector);
 291         return tmp;
 292 }
 293
 294 /*
 295  * Insert a node into the pd->bio_queue rb tree.
 296  */
 297 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 298 {
 299         struct rb_node **p = &pd->bio_queue.rb_node;
 300         struct rb_node *parent = NULL;
 301         sector_t s = node->bio->bi_sector;
 302         struct pkt_rb_node *tmp;
 303
 304         while (*p) {
 305                 parent = *p;
 306                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 307                 if (s < tmp->bio->bi_sector)
 308                         p = &(*p)->rb_left;
 309                 else
 310                         p = &(*p)->rb_right;
 311         }
 312         rb_link_node(&node->rb_node, parent, p);
 313         rb_insert_color(&node->rb_node, &pd->bio_queue);
 314         pd->bio_queue_size++;
 315 }
 316
 317 /*
 318  * Add a bio to a single linked list defined by its head and tail pointers.
 319  */
 320 static inline void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
 321 {
 322         bio->bi_next = NULL;
 323         if (*list_tail) {
 324                 BUG_ON((*list_head) == NULL);
 325                 (*list_tail)->bi_next = bio;
 326                 (*list_tail) = bio;
 327         } else {
 328                 BUG_ON((*list_head) != NULL);
 329                 (*list_head) = bio;
 330                 (*list_tail) = bio;
 331         }
 332 }
 333
 334 /*
 335  * Remove and return the first bio from a single linked list defined by its
 336  * head and tail pointers.
 337  */
 338 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
 339 {
 340         struct bio *bio;
 341
 342         if (*list_head == NULL)
 343                 return NULL;
 344
 345         bio = *list_head;
 346         *list_head = bio->bi_next;
 347         if (*list_head == NULL)
 348                 *list_tail = NULL;
 349
 350         bio->bi_next = NULL;
 351         return bio;
 352 }
 353
 354 /*
 355  * Send a packet_command to the underlying block device and
 356  * wait for completion.
 357  */
 358 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 359 {
 360         char sense[SCSI_SENSE_BUFFERSIZE];
 361         request_queue_t *q;
 362         struct request *rq;
 363         DECLARE_COMPLETION(wait);
 364         int err = 0;
 365
 366         q = bdev_get_queue(pd->bdev);
 367
 368         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ,
 369                              __GFP_WAIT);
 370         rq->errors = 0;
 371         rq->rq_disk = pd->bdev->bd_disk;
 372         rq->bio = NULL;
 373         rq->buffer = NULL;
 374         rq->timeout = 60*HZ;
 375         rq->data = cgc->buffer;
 376         rq->data_len = cgc->buflen;
 377         rq->sense = sense;
 378         memset(sense, 0, sizeof(sense));
 379         rq->sense_len = 0;
 380         rq->flags |= REQ_BLOCK_PC | REQ_HARDBARRIER;
 381         if (cgc->quiet)
 382                 rq->flags |= REQ_QUIET;
 383         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 384         if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
 385                 memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);
 386
 387         rq->ref_count++;
 388         rq->flags |= REQ_NOMERGE;
 389         rq->waiting = &wait;
 390         rq->end_io = blk_end_sync_rq;
 391         elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
 392         generic_unplug_device(q);
 393         wait_for_completion(&wait);
 394
 395         if (rq->errors)
 396                 err = -EIO;
 397
 398         blk_put_request(rq);
 399         return err;
 400 }
 401
 402 /*
 403  * A generic sense dump / resolve mechanism should be implemented across
 404  * all ATAPI + SCSI devices.
 405  */
 406 static void pkt_dump_sense(struct packet_command *cgc)
 407 {
 408         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 409                                  "Medium error", "Hardware error", "Illegal request",
 410                                  "Unit attention", "Data protect", "Blank check" };
 411         int i;
 412         struct request_sense *sense = cgc->sense;
 413
 414         printk("pktcdvd:");
 415         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 416                 printk(" %02x", cgc->cmd[i]);
 417         printk(" - ");
 418
 419         if (sense == NULL) {
 420                 printk("no sense\n");
 421                 return;
 422         }
 423
 424         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 425
 426         if (sense->sense_key > 8) {
 427                 printk(" (INVALID)\n");
 428                 return;
 429         }
 430
 431         printk(" (%s)\n", info[sense->sense_key]);
 432 }
 433
 434 /*
 435  * flush the drive cache to media
 436  */
 437 static int pkt_flush_cache(struct pktcdvd_device *pd)
 438 {
 439         struct packet_command cgc;
 440
 441         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 442         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 443         cgc.quiet = 1;
 444
 445         /*
 446          * the IMMED bit -- we default to not setting it, although that
 447          * would allow a much faster close, this is safer
 448          */
 449 #if 0
 450         cgc.cmd[1] = 1 << 1;
 451 #endif
 452         return pkt_generic_packet(pd, &cgc);
 453 }
 454
 455 /*
 456  * speed is given as the normal factor, e.g. 4 for 4x
 457  */
 458 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
 459 {
 460         struct packet_command cgc;
 461         struct request_sense sense;
 462         int ret;
 463
 464         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 465         cgc.sense = &sense;
 466         cgc.cmd[0] = GPCMD_SET_SPEED;
 467         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 468         cgc.cmd[3] = read_speed & 0xff;
 469         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 470         cgc.cmd[5] = write_speed & 0xff;
 471
 472         if ((ret = pkt_generic_packet(pd, &cgc)))
 473                 pkt_dump_sense(&cgc);
 474
 475         return ret;
 476 }
 477
 478 /*
 479  * Queue a bio for processing by the low-level CD device. Must be called
 480  * from process context.
 481  */
 482 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 483 {
 484         spin_lock(&pd->iosched.lock);
 485         if (bio_data_dir(bio) == READ) {
 486                 pkt_add_list_last(bio, &pd->iosched.read_queue,
 487                                   &pd->iosched.read_queue_tail);
 488         } else {
 489                 pkt_add_list_last(bio, &pd->iosched.write_queue,
 490                                   &pd->iosched.write_queue_tail);
 491         }
 492         spin_unlock(&pd->iosched.lock);
 493
 494         atomic_set(&pd->iosched.attention, 1);
 495         wake_up(&pd->wqueue);
 496 }
 497
 498 /*
 499  * Process the queued read/write requests. This function handles special
 500  * requirements for CDRW drives:
 501  * - A cache flush command must be inserted before a read request if the
 502  *   previous request was a write.
 503  * - Switching between reading and writing is slow, so don't do it more often
 504  *   than necessary.
 505  * - Optimize for throughput at the expense of latency. This means that streaming
 506  *   writes will never be interrupted by a read, but if the drive has to seek
 507  *   before the next write, switch to reading instead if there are any pending
 508  *   read requests.
 509  * - Set the read speed according to current usage pattern. When only reading
 510  *   from the device, it's best to use the highest possible read speed, but
 511  *   when switching often between reading and writing, it's better to have the
 512  *   same read and write speeds.
 513  */
 514 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 515 {
 516         request_queue_t *q;
 517
 518         if (atomic_read(&pd->iosched.attention) == 0)
 519                 return;
 520         atomic_set(&pd->iosched.attention, 0);
 521
 522         q = bdev_get_queue(pd->bdev);
 523
 524         for (;;) {
 525                 struct bio *bio;
 526                 int reads_queued, writes_queued;
 527
 528                 spin_lock(&pd->iosched.lock);
 529                 reads_queued = (pd->iosched.read_queue != NULL);
 530                 writes_queued = (pd->iosched.write_queue != NULL);
 531                 spin_unlock(&pd->iosched.lock);
 532
 533                 if (!reads_queued && !writes_queued)
 534                         break;
 535
 536                 if (pd->iosched.writing) {
 537                         int need_write_seek = 1;
 538                         spin_lock(&pd->iosched.lock);
 539                         bio = pd->iosched.write_queue;
 540                         spin_unlock(&pd->iosched.lock);
 541                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 542                                 need_write_seek = 0;
 543                         if (need_write_seek && reads_queued) {
 544                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 545                                         VPRINTK("pktcdvd: write, waiting\n");
 546                                         break;
 547                                 }
 548                                 pkt_flush_cache(pd);
 549                                 pd->iosched.writing = 0;
 550                         }
 551                 } else {
 552                         if (!reads_queued && writes_queued) {
 553                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 554                                         VPRINTK("pktcdvd: read, waiting\n");
 555                                         break;
 556                                 }
 557                                 pd->iosched.writing = 1;
 558                         }
 559                 }
 560
 561                 spin_lock(&pd->iosched.lock);
 562                 if (pd->iosched.writing) {
 563                         bio = pkt_get_list_first(&pd->iosched.write_queue,
 564                                                  &pd->iosched.write_queue_tail);
 565                 } else {
 566                         bio = pkt_get_list_first(&pd->iosched.read_queue,
 567                                                  &pd->iosched.read_queue_tail);
 568                 }
 569                 spin_unlock(&pd->iosched.lock);
 570
 571                 if (!bio)
 572                         continue;
 573
 574                 if (bio_data_dir(bio) == READ)
 575                         pd->iosched.successive_reads += bio->bi_size >> 10;
 576                 else {
 577                         pd->iosched.successive_reads = 0;
 578                         pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
 579                 }
 580                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 581                         if (pd->read_speed == pd->write_speed) {
 582                                 pd->read_speed = MAX_SPEED;
 583                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 584                         }
 585                 } else {
 586                         if (pd->read_speed != pd->write_speed) {
 587                                 pd->read_speed = pd->write_speed;
 588                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 589                         }
 590                 }
 591
 592                 atomic_inc(&pd->cdrw.pending_bios);
 593                 generic_make_request(bio);
 594         }
 595 }
 596
 597 /*
 598  * Special care is needed if the underlying block device has a small
 599  * max_phys_segments value.
 600  */
 601 static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
 602 {
 603         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 604                 /*
 605                  * The cdrom device can handle one segment/frame
 606                  */
 607                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 608                 return 0;
 609         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
 610                 /*
 611                  * We can handle this case at the expense of some extra memory
 612                  * copies during write operations
 613                  */
 614                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 615                 return 0;
 616         } else {
 617                 printk("pktcdvd: cdrom max_phys_segments too small\n");
 618                 return -EIO;
 619         }
 620 }
 621
 622 /*
 623  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 624  */
 625 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 626 {
 627         unsigned int copy_size = CD_FRAMESIZE;
 628
 629         while (copy_size > 0) {
 630                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 631                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 632                         src_bvl->bv_offset + offs;
 633                 void *vto = page_address(dst_page) + dst_offs;
 634                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 635
 636                 BUG_ON(len < 0);
 637                 memcpy(vto, vfrom, len);
 638                 kunmap_atomic(vfrom, KM_USER0);
 639
 640                 seg++;
 641                 offs = 0;
 642                 dst_offs += len;
 643                 copy_size -= len;
 644         }
 645 }
 646
 647 /*
 648  * Copy all data for this packet to pkt->pages[], so that
 649  * a) The number of required segments for the write bio is minimized, which
 650  *    is necessary for some scsi controllers.
 651  * b) The data can be used as cache to avoid read requests if we receive a
 652  *    new write request for the same zone.
 653  */
 654 static void pkt_make_local_copy(struct packet_data *pkt, struct page **pages, int *offsets)
 655 {
 656         int f, p, offs;
 657
 658         /* Copy all data to pkt->pages[] */
 659         p = 0;
 660         offs = 0;
 661         for (f = 0; f < pkt->frames; f++) {
 662                 if (pages[f] != pkt->pages[p]) {
 663                         void *vfrom = kmap_atomic(pages[f], KM_USER0) + offsets[f];
 664                         void *vto = page_address(pkt->pages[p]) + offs;
 665                         memcpy(vto, vfrom, CD_FRAMESIZE);
 666                         kunmap_atomic(vfrom, KM_USER0);
 667                         pages[f] = pkt->pages[p];
 668                         offsets[f] = offs;
 669                 } else {
 670                         BUG_ON(offsets[f] != offs);
 671                 }
 672                 offs += CD_FRAMESIZE;
 673                 if (offs >= PAGE_SIZE) {
 674                         BUG_ON(offs > PAGE_SIZE);
 675                         offs = 0;
 676                         p++;
 677                 }
 678         }
 679 }
 680
 681 static int pkt_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
 682 {
 683         struct packet_data *pkt = bio->bi_private;
 684         struct pktcdvd_device *pd = pkt->pd;
 685         BUG_ON(!pd);
 686
 687         if (bio->bi_size)
 688                 return 1;
 689
 690         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 691                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 692
 693         if (err)
 694                 atomic_inc(&pkt->io_errors);
 695         if (atomic_dec_and_test(&pkt->io_wait)) {
 696                 atomic_inc(&pkt->run_sm);
 697                 wake_up(&pd->wqueue);
 698         }
 699         pkt_bio_finished(pd);
 700
 701         return 0;
 702 }
 703
 704 static int pkt_end_io_packet_write(struct bio *bio, unsigned int bytes_done, int err)
 705 {
 706         struct packet_data *pkt = bio->bi_private;
 707         struct pktcdvd_device *pd = pkt->pd;
 708         BUG_ON(!pd);
 709
 710         if (bio->bi_size)
 711                 return 1;
 712
 713         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
 714
 715         pd->stats.pkt_ended++;
 716
 717         pkt_bio_finished(pd);
 718         atomic_dec(&pkt->io_wait);
 719         atomic_inc(&pkt->run_sm);
 720         wake_up(&pd->wqueue);
 721         return 0;
 722 }
 723
 724 /*
 725  * Schedule reads for the holes in a packet
 726  */
 727 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 728 {
 729         int frames_read = 0;
 730         struct bio *bio;
 731         int f;
 732         char written[PACKET_MAX_SIZE];
 733
 734         BUG_ON(!pkt->orig_bios);
 735
 736         atomic_set(&pkt->io_wait, 0);
 737         atomic_set(&pkt->io_errors, 0);
 738
 739         if (pkt->cache_valid) {
 740                 VPRINTK("pkt_gather_data: zone %llx cached\n",
 741                         (unsigned long long)pkt->sector);
 742                 goto out_account;
 743         }
 744
 745         /*
 746          * Figure out which frames we need to read before we can write.
 747          */
 748         memset(written, 0, sizeof(written));
 749         spin_lock(&pkt->lock);
 750         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
 751                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
 752                 int num_frames = bio->bi_size / CD_FRAMESIZE;
 753                 BUG_ON(first_frame < 0);
 754                 BUG_ON(first_frame + num_frames > pkt->frames);
 755                 for (f = first_frame; f < first_frame + num_frames; f++)
 756                         written[f] = 1;
 757         }
 758         spin_unlock(&pkt->lock);
 759
 760         /*
 761          * Schedule reads for missing parts of the packet.
 762          */
 763         for (f = 0; f < pkt->frames; f++) {
 764                 int p, offset;
 765                 if (written[f])
 766                         continue;
 767                 bio = pkt->r_bios[f];
 768                 bio_init(bio);
 769                 bio->bi_max_vecs = 1;
 770                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 771                 bio->bi_bdev = pd->bdev;
 772                 bio->bi_end_io = pkt_end_io_read;
 773                 bio->bi_private = pkt;
 774
 775                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
 776                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 777                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
 778                         f, pkt->pages[p], offset);
 779                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
 780                         BUG();
 781
 782                 atomic_inc(&pkt->io_wait);
 783                 bio->bi_rw = READ;
 784                 pkt_queue_bio(pd, bio);
 785                 frames_read++;
 786         }
 787
 788 out_account:
 789         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
 790                 frames_read, (unsigned long long)pkt->sector);
 791         pd->stats.pkt_started++;
 792         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
 793         pd->stats.secs_w += pd->settings.size;
 794 }
 795
 796 /*
 797  * Find a packet matching zone, or the least recently used packet if
 798  * there is no match.
 799  */
 800 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
 801 {
 802         struct packet_data *pkt;
 803
 804         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
 805                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
 806                         list_del_init(&pkt->list);
 807                         if (pkt->sector != zone)
 808                                 pkt->cache_valid = 0;
 809                         break;
 810                 }
 811         }
 812         return pkt;
 813 }
 814
 815 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 816 {
 817         if (pkt->cache_valid) {
 818                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 819         } else {
 820                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
 821         }
 822 }
 823
 824 /*
 825  * recover a failed write, query for relocation if possible
 826  *
 827  * returns 1 if recovery is possible, or 0 if not
 828  *
 829  */
 830 static int pkt_start_recovery(struct packet_data *pkt)
 831 {
 832         /*
 833          * FIXME. We need help from the file system to implement
 834          * recovery handling.
 835          */
 836         return 0;
 837 #if 0
 838         struct request *rq = pkt->rq;
 839         struct pktcdvd_device *pd = rq->rq_disk->private_data;
 840         struct block_device *pkt_bdev;
 841         struct super_block *sb = NULL;
 842         unsigned long old_block, new_block;
 843         sector_t new_sector;
 844
 845         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
 846         if (pkt_bdev) {
 847                 sb = get_super(pkt_bdev);
 848                 bdput(pkt_bdev);
 849         }
 850
 851         if (!sb)
 852                 return 0;
 853
 854         if (!sb->s_op || !sb->s_op->relocate_blocks)
 855                 goto out;
 856
 857         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
 858         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
 859                 goto out;
 860
 861         new_sector = new_block * (CD_FRAMESIZE >> 9);
 862         pkt->sector = new_sector;
 863
 864         pkt->bio->bi_sector = new_sector;
 865         pkt->bio->bi_next = NULL;
 866         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
 867         pkt->bio->bi_idx = 0;
 868
 869         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
 870         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
 871         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
 872         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
 873         BUG_ON(pkt->bio->bi_private != pkt);
 874
 875         drop_super(sb);
 876         return 1;
 877
 878 out:
 879         drop_super(sb);
 880         return 0;
 881 #endif
 882 }
 883
 884 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
 885 {
 886 #if PACKET_DEBUG > 1
 887         static const char *state_name[] = {
 888                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
 889         };
 890         enum packet_data_state old_state = pkt->state;
 891         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
 892                 state_name[old_state], state_name[state]);
 893 #endif
 894         pkt->state = state;
 895 }
 896
 897 /*
 898  * Scan the work queue to see if we can start a new packet.
 899  * returns non-zero if any work was done.
 900  */
 901 static int pkt_handle_queue(struct pktcdvd_device *pd)
 902 {
 903         struct packet_data *pkt, *p;
 904         struct bio *bio = NULL;
 905         sector_t zone = 0; /* Suppress gcc warning */
 906         struct pkt_rb_node *node, *first_node;
 907         struct rb_node *n;
 908
 909         VPRINTK("handle_queue\n");
 910
 911         atomic_set(&pd->scan_queue, 0);
 912
 913         if (list_empty(&pd->cdrw.pkt_free_list)) {
 914                 VPRINTK("handle_queue: no pkt\n");
 915                 return 0;
 916         }
 917
 918         /*
 919          * Try to find a zone we are not already working on.
 920          */
 921         spin_lock(&pd->lock);
 922         first_node = pkt_rbtree_find(pd, pd->current_sector);
 923         if (!first_node) {
 924                 n = rb_first(&pd->bio_queue);
 925                 if (n)
 926                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
 927         }
 928         node = first_node;
 929         while (node) {
 930                 bio = node->bio;
 931                 zone = ZONE(bio->bi_sector, pd);
 932                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
 933                         if (p->sector == zone) {
 934                                 bio = NULL;
 935                                 goto try_next_bio;
 936                         }
 937                 }
 938                 break;
 939 try_next_bio:
 940                 node = pkt_rbtree_next(node);
 941                 if (!node) {
 942                         n = rb_first(&pd->bio_queue);
 943                         if (n)
 944                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
 945                 }
 946                 if (node == first_node)
 947                         node = NULL;
 948         }
 949         spin_unlock(&pd->lock);
 950         if (!bio) {
 951                 VPRINTK("handle_queue: no bio\n");
 952                 return 0;
 953         }
 954
 955         pkt = pkt_get_packet_data(pd, zone);
 956         BUG_ON(!pkt);
 957
 958         pd->current_sector = zone + pd->settings.size;
 959         pkt->sector = zone;
 960         pkt->frames = pd->settings.size >> 2;
 961         pkt->write_size = 0;
 962
 963         /*
 964          * Scan work queue for bios in the same zone and link them
 965          * to this packet.
 966          */
 967         spin_lock(&pd->lock);
 968         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
 969         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
 970                 bio = node->bio;
 971                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
 972                         (unsigned long long)ZONE(bio->bi_sector, pd));
 973                 if (ZONE(bio->bi_sector, pd) != zone)
 974                         break;
 975                 pkt_rbtree_erase(pd, node);
 976                 spin_lock(&pkt->lock);
 977                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
 978                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
 979                 spin_unlock(&pkt->lock);
 980         }
 981         spin_unlock(&pd->lock);
 982
 983         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
 984         pkt_set_state(pkt, PACKET_WAITING_STATE);
 985         atomic_set(&pkt->run_sm, 1);
 986
 987         spin_lock(&pd->cdrw.active_list_lock);
 988         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
 989         spin_unlock(&pd->cdrw.active_list_lock);
 990
 991         return 1;
 992 }
 993
 994 /*
 995  * Assemble a bio to write one packet and queue the bio for processing
 996  * by the underlying block device.
 997  */
 998 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 999 {
1000         struct bio *bio;
1001         struct page *pages[PACKET_MAX_SIZE];
1002         int offsets[PACKET_MAX_SIZE];
1003         int f;
1004         int frames_write;
1005
1006         for (f = 0; f < pkt->frames; f++) {
1007                 pages[f] = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1008                 offsets[f] = (f * CD_FRAMESIZE) % PAGE_SIZE;
1009         }
1010
1011         /*
1012          * Fill-in pages[] and offsets[] with data from orig_bios.
1013          */
1014         frames_write = 0;
1015         spin_lock(&pkt->lock);
1016         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1017                 int segment = bio->bi_idx;
1018                 int src_offs = 0;
1019                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1020                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1021                 BUG_ON(first_frame < 0);
1022                 BUG_ON(first_frame + num_frames > pkt->frames);
1023                 for (f = first_frame; f < first_frame + num_frames; f++) {
1024                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1025
1026                         while (src_offs >= src_bvl->bv_len) {
1027                                 src_offs -= src_bvl->bv_len;
1028                                 segment++;
1029                                 BUG_ON(segment >= bio->bi_vcnt);
1030                                 src_bvl = bio_iovec_idx(bio, segment);
1031                         }
1032
1033                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1034                                 pages[f] = src_bvl->bv_page;
1035                                 offsets[f] = src_bvl->bv_offset + src_offs;
1036                         } else {
1037                                 pkt_copy_bio_data(bio, segment, src_offs,
1038                                                   pages[f], offsets[f]);
1039                         }
1040                         src_offs += CD_FRAMESIZE;
1041                         frames_write++;
1042                 }
1043         }
1044         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1045         spin_unlock(&pkt->lock);
1046
1047         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1048                 frames_write, (unsigned long long)pkt->sector);
1049         BUG_ON(frames_write != pkt->write_size);
1050
1051         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1052                 pkt_make_local_copy(pkt, pages, offsets);
1053                 pkt->cache_valid = 1;
1054         } else {
1055                 pkt->cache_valid = 0;
1056         }
1057
1058         /* Start the write request */
1059         bio_init(pkt->w_bio);
1060         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1061         pkt->w_bio->bi_sector = pkt->sector;
1062         pkt->w_bio->bi_bdev = pd->bdev;
1063         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1064         pkt->w_bio->bi_private = pkt;
1065         for (f = 0; f < pkt->frames; f++) {
1066                 if ((f + 1 < pkt->frames) && (pages[f + 1] == pages[f]) &&
1067                     (offsets[f + 1] = offsets[f] + CD_FRAMESIZE)) {
1068                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE * 2, offsets[f]))
1069                                 BUG();
1070                         f++;
1071                 } else {
1072                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE, offsets[f]))
1073                                 BUG();
1074                 }
1075         }
1076         VPRINTK("pktcdvd: vcnt=%d\n", pkt->w_bio->bi_vcnt);
1077
1078         atomic_set(&pkt->io_wait, 1);
1079         pkt->w_bio->bi_rw = WRITE;
1080         pkt_queue_bio(pd, pkt->w_bio);
1081 }
1082
1083 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1084 {
1085         struct bio *bio, *next;
1086
1087         if (!uptodate)
1088                 pkt->cache_valid = 0;
1089
1090         /* Finish all bios corresponding to this packet */
1091         bio = pkt->orig_bios;
1092         while (bio) {
1093                 next = bio->bi_next;
1094                 bio->bi_next = NULL;
1095                 bio_endio(bio, bio->bi_size, uptodate ? 0 : -EIO);
1096                 bio = next;
1097         }
1098         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1099 }
1100
1101 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1102 {
1103         int uptodate;
1104
1105         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1106
1107         for (;;) {
1108                 switch (pkt->state) {
1109                 case PACKET_WAITING_STATE:
1110                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1111                                 return;
1112
1113                         pkt->sleep_time = 0;
1114                         pkt_gather_data(pd, pkt);
1115                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1116                         break;
1117
1118                 case PACKET_READ_WAIT_STATE:
1119                         if (atomic_read(&pkt->io_wait) > 0)
1120                                 return;
1121
1122                         if (atomic_read(&pkt->io_errors) > 0) {
1123                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1124                         } else {
1125                                 pkt_start_write(pd, pkt);
1126                         }
1127                         break;
1128
1129                 case PACKET_WRITE_WAIT_STATE:
1130                         if (atomic_read(&pkt->io_wait) > 0)
1131                                 return;
1132
1133                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1134                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1135                         } else {
1136                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1137                         }
1138                         break;
1139
1140                 case PACKET_RECOVERY_STATE:
1141                         if (pkt_start_recovery(pkt)) {
1142                                 pkt_start_write(pd, pkt);
1143                         } else {
1144                                 VPRINTK("No recovery possible\n");
1145                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1146                         }
1147                         break;
1148
1149                 case PACKET_FINISHED_STATE:
1150                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1151                         pkt_finish_packet(pkt, uptodate);
1152                         return;
1153
1154                 default:
1155                         BUG();
1156                         break;
1157                 }
1158         }
1159 }
1160
1161 static void pkt_handle_packets(struct pktcdvd_device *pd)
1162 {
1163         struct packet_data *pkt, *next;
1164
1165         VPRINTK("pkt_handle_packets\n");
1166
1167         /*
1168          * Run state machine for active packets
1169          */
1170         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1171                 if (atomic_read(&pkt->run_sm) > 0) {
1172                         atomic_set(&pkt->run_sm, 0);
1173                         pkt_run_state_machine(pd, pkt);
1174                 }
1175         }
1176
1177         /*
1178          * Move no longer active packets to the free list
1179          */
1180         spin_lock(&pd->cdrw.active_list_lock);
1181         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1182                 if (pkt->state == PACKET_FINISHED_STATE) {
1183                         list_del(&pkt->list);
1184                         pkt_put_packet_data(pd, pkt);
1185                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1186                         atomic_set(&pd->scan_queue, 1);
1187                 }
1188         }
1189         spin_unlock(&pd->cdrw.active_list_lock);
1190 }
1191
1192 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1193 {
1194         struct packet_data *pkt;
1195         int i;
1196
1197         for (i = 0; i <= PACKET_NUM_STATES; i++)
1198                 states[i] = 0;
1199
1200         spin_lock(&pd->cdrw.active_list_lock);
1201         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1202                 states[pkt->state]++;
1203         }
1204         spin_unlock(&pd->cdrw.active_list_lock);
1205 }
1206
1207 /*
1208  * kcdrwd is woken up when writes have been queued for one of our
1209  * registered devices
1210  */
1211 static int kcdrwd(void *foobar)
1212 {
1213         struct pktcdvd_device *pd = foobar;
1214         struct packet_data *pkt;
1215         long min_sleep_time, residue;
1216
1217         set_user_nice(current, -20);
1218
1219         for (;;) {
1220                 DECLARE_WAITQUEUE(wait, current);
1221
1222                 /*
1223                  * Wait until there is something to do
1224                  */
1225                 add_wait_queue(&pd->wqueue, &wait);
1226                 for (;;) {
1227                         set_current_state(TASK_INTERRUPTIBLE);
1228
1229                         /* Check if we need to run pkt_handle_queue */
1230                         if (atomic_read(&pd->scan_queue) > 0)
1231                                 goto work_to_do;
1232
1233                         /* Check if we need to run the state machine for some packet */
1234                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1235                                 if (atomic_read(&pkt->run_sm) > 0)
1236                                         goto work_to_do;
1237                         }
1238
1239                         /* Check if we need to process the iosched queues */
1240                         if (atomic_read(&pd->iosched.attention) != 0)
1241                                 goto work_to_do;
1242
1243                         /* Otherwise, go to sleep */
1244                         if (PACKET_DEBUG > 1) {
1245                                 int states[PACKET_NUM_STATES];
1246                                 pkt_count_states(pd, states);
1247                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1248                                         states[0], states[1], states[2], states[3],
1249                                         states[4], states[5]);
1250                         }
1251
1252                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1253                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1254                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1255                                         min_sleep_time = pkt->sleep_time;
1256                         }
1257
1258                         generic_unplug_device(bdev_get_queue(pd->bdev));
1259
1260                         VPRINTK("kcdrwd: sleeping\n");
1261                         residue = schedule_timeout(min_sleep_time);
1262                         VPRINTK("kcdrwd: wake up\n");
1263
1264                         /* make swsusp happy with our thread */
1265                         try_to_freeze();
1266
1267                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1268                                 if (!pkt->sleep_time)
1269                                         continue;
1270                                 pkt->sleep_time -= min_sleep_time - residue;
1271                                 if (pkt->sleep_time <= 0) {
1272                                         pkt->sleep_time = 0;
1273                                         atomic_inc(&pkt->run_sm);
1274                                 }
1275                         }
1276
1277                         if (signal_pending(current)) {
1278                                 flush_signals(current);
1279                         }
1280                         if (kthread_should_stop())
1281                                 break;
1282                 }
1283 work_to_do:
1284                 set_current_state(TASK_RUNNING);
1285                 remove_wait_queue(&pd->wqueue, &wait);
1286
1287                 if (kthread_should_stop())
1288                         break;
1289
1290                 /*
1291                  * if pkt_handle_queue returns true, we can queue
1292                  * another request.
1293                  */
1294                 while (pkt_handle_queue(pd))
1295                         ;
1296
1297                 /*
1298                  * Handle packet state machine
1299                  */
1300                 pkt_handle_packets(pd);
1301
1302                 /*
1303                  * Handle iosched queues
1304                  */
1305                 pkt_iosched_process_queue(pd);
1306         }
1307
1308         return 0;
1309 }
1310
1311 static void pkt_print_settings(struct pktcdvd_device *pd)
1312 {
1313         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1314         printk("%u blocks, ", pd->settings.size >> 2);
1315         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1316 }
1317
1318 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1319 {
1320         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1321
1322         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1323         cgc->cmd[2] = page_code | (page_control << 6);
1324         cgc->cmd[7] = cgc->buflen >> 8;
1325         cgc->cmd[8] = cgc->buflen & 0xff;
1326         cgc->data_direction = CGC_DATA_READ;
1327         return pkt_generic_packet(pd, cgc);
1328 }
1329
1330 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1331 {
1332         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1333         memset(cgc->buffer, 0, 2);
1334         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1335         cgc->cmd[1] = 0x10;             /* PF */
1336         cgc->cmd[7] = cgc->buflen >> 8;
1337         cgc->cmd[8] = cgc->buflen & 0xff;
1338         cgc->data_direction = CGC_DATA_WRITE;
1339         return pkt_generic_packet(pd, cgc);
1340 }
1341
1342 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1343 {
1344         struct packet_command cgc;
1345         int ret;
1346
1347         /* set up command and get the disc info */
1348         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1349         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1350         cgc.cmd[8] = cgc.buflen = 2;
1351         cgc.quiet = 1;
1352
1353         if ((ret = pkt_generic_packet(pd, &cgc)))
1354                 return ret;
1355
1356         /* not all drives have the same disc_info length, so requeue
1357          * packet with the length the drive tells us it can supply
1358          */
1359         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1360                      sizeof(di->disc_information_length);
1361
1362         if (cgc.buflen > sizeof(disc_information))
1363                 cgc.buflen = sizeof(disc_information);
1364
1365         cgc.cmd[8] = cgc.buflen;
1366         return pkt_generic_packet(pd, &cgc);
1367 }
1368
1369 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1370 {
1371         struct packet_command cgc;
1372         int ret;
1373
1374         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1375         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1376         cgc.cmd[1] = type & 3;
1377         cgc.cmd[4] = (track & 0xff00) >> 8;
1378         cgc.cmd[5] = track & 0xff;
1379         cgc.cmd[8] = 8;
1380         cgc.quiet = 1;
1381
1382         if ((ret = pkt_generic_packet(pd, &cgc)))
1383                 return ret;
1384
1385         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1386                      sizeof(ti->track_information_length);
1387
1388         if (cgc.buflen > sizeof(track_information))
1389                 cgc.buflen = sizeof(track_information);
1390
1391         cgc.cmd[8] = cgc.buflen;
1392         return pkt_generic_packet(pd, &cgc);
1393 }
1394
1395 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1396 {
1397         disc_information di;
1398         track_information ti;
1399         __u32 last_track;
1400         int ret = -1;
1401
1402         if ((ret = pkt_get_disc_info(pd, &di)))
1403                 return ret;
1404
1405         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1406         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1407                 return ret;
1408
1409         /* if this track is blank, try the previous. */
1410         if (ti.blank) {
1411                 last_track--;
1412                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1413                         return ret;
1414         }
1415
1416         /* if last recorded field is valid, return it. */
1417         if (ti.lra_v) {
1418                 *last_written = be32_to_cpu(ti.last_rec_address);
1419         } else {
1420                 /* make it up instead */
1421                 *last_written = be32_to_cpu(ti.track_start) +
1422                                 be32_to_cpu(ti.track_size);
1423                 if (ti.free_blocks)
1424                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1425         }
1426         return 0;
1427 }
1428
1429 /*
1430  * write mode select package based on pd->settings
1431  */
1432 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1433 {
1434         struct packet_command cgc;
1435         struct request_sense sense;
1436         write_param_page *wp;
1437         char buffer[128];
1438         int ret, size;
1439
1440         /* doesn't apply to DVD+RW or DVD-RAM */
1441         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1442                 return 0;
1443
1444         memset(buffer, 0, sizeof(buffer));
1445         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1446         cgc.sense = &sense;
1447         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1448                 pkt_dump_sense(&cgc);
1449                 return ret;
1450         }
1451
1452         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1453         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1454         if (size > sizeof(buffer))
1455                 size = sizeof(buffer);
1456
1457         /*
1458          * now get it all
1459          */
1460         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1461         cgc.sense = &sense;
1462         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1463                 pkt_dump_sense(&cgc);
1464                 return ret;
1465         }
1466
1467         /*
1468          * write page is offset header + block descriptor length
1469          */
1470         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1471
1472         wp->fp = pd->settings.fp;
1473         wp->track_mode = pd->settings.track_mode;
1474         wp->write_type = pd->settings.write_type;
1475         wp->data_block_type = pd->settings.block_mode;
1476
1477         wp->multi_session = 0;
1478
1479 #ifdef PACKET_USE_LS
1480         wp->link_size = 7;
1481         wp->ls_v = 1;
1482 #endif
1483
1484         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1485                 wp->session_format = 0;
1486                 wp->subhdr2 = 0x20;
1487         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1488                 wp->session_format = 0x20;
1489                 wp->subhdr2 = 8;
1490 #if 0
1491                 wp->mcn[0] = 0x80;
1492                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1493 #endif
1494         } else {
1495                 /*
1496                  * paranoia
1497                  */
1498                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1499                 return 1;
1500         }
1501         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1502
1503         cgc.buflen = cgc.cmd[8] = size;
1504         if ((ret = pkt_mode_select(pd, &cgc))) {
1505                 pkt_dump_sense(&cgc);
1506                 return ret;
1507         }
1508
1509         pkt_print_settings(pd);
1510         return 0;
1511 }
1512
1513 /*
1514  * 0 -- we can write to this track, 1 -- we can't
1515  */
1516 static int pkt_good_track(track_information *ti)
1517 {
1518         /*
1519          * only good for CD-RW at the moment, not DVD-RW
1520          */
1521
1522         /*
1523          * FIXME: only for FP
1524          */
1525         if (ti->fp == 0)
1526                 return 0;
1527
1528         /*
1529          * "good" settings as per Mt Fuji.
1530          */
1531         if (ti->rt == 0 && ti->blank == 0 && ti->packet == 1)
1532                 return 0;
1533
1534         if (ti->rt == 0 && ti->blank == 1 && ti->packet == 1)
1535                 return 0;
1536
1537         if (ti->rt == 1 && ti->blank == 0 && ti->packet == 1)
1538                 return 0;
1539
1540         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1541         return 1;
1542 }
1543
1544 /*
1545  * 0 -- we can write to this disc, 1 -- we can't
1546  */
1547 static int pkt_good_disc(struct pktcdvd_device *pd, disc_information *di)
1548 {
1549         switch (pd->mmc3_profile) {
1550                 case 0x0a: /* CD-RW */
1551                 case 0xffff: /* MMC3 not supported */
1552                         break;
1553                 case 0x1a: /* DVD+RW */
1554                 case 0x13: /* DVD-RW */
1555                 case 0x12: /* DVD-RAM */
1556                         return 0;
1557                 default:
1558                         printk("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1559                         return 1;
1560         }
1561
1562         /*
1563          * for disc type 0xff we should probably reserve a new track.
1564          * but i'm not sure, should we leave this to user apps? probably.
1565          */
1566         if (di->disc_type == 0xff) {
1567                 printk("pktcdvd: Unknown disc. No track?\n");
1568                 return 1;
1569         }
1570
1571         if (di->disc_type != 0x20 && di->disc_type != 0) {
1572                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1573                 return 1;
1574         }
1575
1576         if (di->erasable == 0) {
1577                 printk("pktcdvd: Disc not erasable\n");
1578                 return 1;
1579         }
1580
1581         if (di->border_status == PACKET_SESSION_RESERVED) {
1582                 printk("pktcdvd: Can't write to last track (reserved)\n");
1583                 return 1;
1584         }
1585
1586         return 0;
1587 }
1588
1589 static int pkt_probe_settings(struct pktcdvd_device *pd)
1590 {
1591         struct packet_command cgc;
1592         unsigned char buf[12];
1593         disc_information di;
1594         track_information ti;
1595         int ret, track;
1596
1597         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1598         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1599         cgc.cmd[8] = 8;
1600         ret = pkt_generic_packet(pd, &cgc);
1601         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1602
1603         memset(&di, 0, sizeof(disc_information));
1604         memset(&ti, 0, sizeof(track_information));
1605
1606         if ((ret = pkt_get_disc_info(pd, &di))) {
1607                 printk("failed get_disc\n");
1608                 return ret;
1609         }
1610
1611         if (pkt_good_disc(pd, &di))
1612                 return -ENXIO;
1613
1614         switch (pd->mmc3_profile) {
1615                 case 0x1a: /* DVD+RW */
1616                         printk("pktcdvd: inserted media is DVD+RW\n");
1617                         break;
1618                 case 0x13: /* DVD-RW */
1619                         printk("pktcdvd: inserted media is DVD-RW\n");
1620                         break;
1621                 case 0x12: /* DVD-RAM */
1622                         printk("pktcdvd: inserted media is DVD-RAM\n");
1623                         break;
1624                 default:
1625                         printk("pktcdvd: inserted media is CD-R%s\n", di.erasable ? "W" : "");
1626                         break;
1627         }
1628         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1629
1630         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1631         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1632                 printk("pktcdvd: failed get_track\n");
1633                 return ret;
1634         }
1635
1636         if (pkt_good_track(&ti)) {
1637                 printk("pktcdvd: can't write to this track\n");
1638                 return -ENXIO;
1639         }
1640
1641         /*
1642          * we keep packet size in 512 byte units, makes it easier to
1643          * deal with request calculations.
1644          */
1645         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1646         if (pd->settings.size == 0) {
1647                 printk("pktcdvd: detected zero packet size!\n");
1648                 pd->settings.size = 128;
1649         }
1650         if (pd->settings.size > PACKET_MAX_SECTORS) {
1651                 printk("pktcdvd: packet size is too big\n");
1652                 return -ENXIO;
1653         }
1654         pd->settings.fp = ti.fp;
1655         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1656
1657         if (ti.nwa_v) {
1658                 pd->nwa = be32_to_cpu(ti.next_writable);
1659                 set_bit(PACKET_NWA_VALID, &pd->flags);
1660         }
1661
1662         /*
1663          * in theory we could use lra on -RW media as well and just zero
1664          * blocks that haven't been written yet, but in practice that
1665          * is just a no-go. we'll use that for -R, naturally.
1666          */
1667         if (ti.lra_v) {
1668                 pd->lra = be32_to_cpu(ti.last_rec_address);
1669                 set_bit(PACKET_LRA_VALID, &pd->flags);
1670         } else {
1671                 pd->lra = 0xffffffff;
1672                 set_bit(PACKET_LRA_VALID, &pd->flags);
1673         }
1674
1675         /*
1676          * fine for now
1677          */
1678         pd->settings.link_loss = 7;
1679         pd->settings.write_type = 0;    /* packet */
1680         pd->settings.track_mode = ti.track_mode;
1681
1682         /*
1683          * mode1 or mode2 disc
1684          */
1685         switch (ti.data_mode) {
1686                 case PACKET_MODE1:
1687                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1688                         break;
1689                 case PACKET_MODE2:
1690                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1691                         break;
1692                 default:
1693                         printk("pktcdvd: unknown data mode\n");
1694                         return 1;
1695         }
1696         return 0;
1697 }
1698
1699 /*
1700  * enable/disable write caching on drive
1701  */
1702 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1703 {
1704         struct packet_command cgc;
1705         struct request_sense sense;
1706         unsigned char buf[64];
1707         int ret;
1708
1709         memset(buf, 0, sizeof(buf));
1710         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1711         cgc.sense = &sense;
1712         cgc.buflen = pd->mode_offset + 12;
1713
1714         /*
1715          * caching mode page might not be there, so quiet this command
1716          */
1717         cgc.quiet = 1;
1718
1719         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1720                 return ret;
1721
1722         buf[pd->mode_offset + 10] |= (!!set << 2);
1723
1724         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1725         ret = pkt_mode_select(pd, &cgc);
1726         if (ret) {
1727                 printk("pktcdvd: write caching control failed\n");
1728                 pkt_dump_sense(&cgc);
1729         } else if (!ret && set)
1730                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1731         return ret;
1732 }
1733
1734 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1735 {
1736         struct packet_command cgc;
1737
1738         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1739         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1740         cgc.cmd[4] = lockflag ? 1 : 0;
1741         return pkt_generic_packet(pd, &cgc);
1742 }
1743
1744 /*
1745  * Returns drive maximum write speed
1746  */
1747 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1748 {
1749         struct packet_command cgc;
1750         struct request_sense sense;
1751         unsigned char buf[256+18];
1752         unsigned char *cap_buf;
1753         int ret, offset;
1754
1755         memset(buf, 0, sizeof(buf));
1756         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1757         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1758         cgc.sense = &sense;
1759
1760         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1761         if (ret) {
1762                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1763                              sizeof(struct mode_page_header);
1764                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1765                 if (ret) {
1766                         pkt_dump_sense(&cgc);
1767                         return ret;
1768                 }
1769         }
1770
1771         offset = 20;                        /* Obsoleted field, used by older drives */
1772         if (cap_buf[1] >= 28)
1773                 offset = 28;                /* Current write speed selected */
1774         if (cap_buf[1] >= 30) {
1775                 /* If the drive reports at least one "Logical Unit Write
1776                  * Speed Performance Descriptor Block", use the information
1777                  * in the first block. (contains the highest speed)
1778                  */
1779                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1780                 if (num_spdb > 0)
1781                         offset = 34;
1782         }
1783
1784         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1785         return 0;
1786 }
1787
1788 /* These tables from cdrecord - I don't have orange book */
1789 /* standard speed CD-RW (1-4x) */
1790 static char clv_to_speed[16] = {
1791         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1792            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1793 };
1794 /* high speed CD-RW (-10x) */
1795 static char hs_clv_to_speed[16] = {
1796         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1797            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1798 };
1799 /* ultra high speed CD-RW */
1800 static char us_clv_to_speed[16] = {
1801         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1802            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1803 };
1804
1805 /*
1806  * reads the maximum media speed from ATIP
1807  */
1808 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1809 {
1810         struct packet_command cgc;
1811         struct request_sense sense;
1812         unsigned char buf[64];
1813         unsigned int size, st, sp;
1814         int ret;
1815
1816         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1817         cgc.sense = &sense;
1818         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1819         cgc.cmd[1] = 2;
1820         cgc.cmd[2] = 4; /* READ ATIP */
1821         cgc.cmd[8] = 2;
1822         ret = pkt_generic_packet(pd, &cgc);
1823         if (ret) {
1824                 pkt_dump_sense(&cgc);
1825                 return ret;
1826         }
1827         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1828         if (size > sizeof(buf))
1829                 size = sizeof(buf);
1830
1831         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1832         cgc.sense = &sense;
1833         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1834         cgc.cmd[1] = 2;
1835         cgc.cmd[2] = 4;
1836         cgc.cmd[8] = size;
1837         ret = pkt_generic_packet(pd, &cgc);
1838         if (ret) {
1839                 pkt_dump_sense(&cgc);
1840                 return ret;
1841         }
1842
1843         if (!buf[6] & 0x40) {
1844                 printk("pktcdvd: Disc type is not CD-RW\n");
1845                 return 1;
1846         }
1847         if (!buf[6] & 0x4) {
1848                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1849                 return 1;
1850         }
1851
1852         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1853
1854         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1855
1856         /* Info from cdrecord */
1857         switch (st) {
1858                 case 0: /* standard speed */
1859                         *speed = clv_to_speed[sp];
1860                         break;
1861                 case 1: /* high speed */
1862                         *speed = hs_clv_to_speed[sp];
1863                         break;
1864                 case 2: /* ultra high speed */
1865                         *speed = us_clv_to_speed[sp];
1866                         break;
1867                 default:
1868                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1869                         return 1;
1870         }
1871         if (*speed) {
1872                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1873                 return 0;
1874         } else {
1875                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1876                 return 1;
1877         }
1878 }
1879
1880 static int pkt_perform_opc(struct pktcdvd_device *pd)
1881 {
1882         struct packet_command cgc;
1883         struct request_sense sense;
1884         int ret;
1885
1886         VPRINTK("pktcdvd: Performing OPC\n");
1887
1888         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1889         cgc.sense = &sense;
1890         cgc.timeout = 60*HZ;
1891         cgc.cmd[0] = GPCMD_SEND_OPC;
1892         cgc.cmd[1] = 1;
1893         if ((ret = pkt_generic_packet(pd, &cgc)))
1894                 pkt_dump_sense(&cgc);
1895         return ret;
1896 }
1897
1898 static int pkt_open_write(struct pktcdvd_device *pd)
1899 {
1900         int ret;
1901         unsigned int write_speed, media_write_speed, read_speed;
1902
1903         if ((ret = pkt_probe_settings(pd))) {
1904                 DPRINTK("pktcdvd: %s failed probe\n", pd->name);
1905                 return -EIO;
1906         }
1907
1908         if ((ret = pkt_set_write_settings(pd))) {
1909                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1910                 return -EIO;
1911         }
1912
1913         pkt_write_caching(pd, USE_WCACHING);
1914
1915         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1916                 write_speed = 16 * 177;
1917         switch (pd->mmc3_profile) {
1918                 case 0x13: /* DVD-RW */
1919                 case 0x1a: /* DVD+RW */
1920                 case 0x12: /* DVD-RAM */
1921                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1922                         break;
1923                 default:
1924                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1925                                 media_write_speed = 16;
1926                         write_speed = min(write_speed, media_write_speed * 177);
1927                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1928                         break;
1929         }
1930         read_speed = write_speed;
1931
1932         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1933                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1934                 return -EIO;
1935         }
1936         pd->write_speed = write_speed;
1937         pd->read_speed = read_speed;
1938
1939         if ((ret = pkt_perform_opc(pd))) {
1940                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1941         }
1942
1943         return 0;
1944 }
1945
1946 /*
1947  * called at open time.
1948  */
1949 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1950 {
1951         int ret;
1952         long lba;
1953         request_queue_t *q;
1954
1955         /*
1956          * We need to re-open the cdrom device without O_NONBLOCK to be able
1957          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1958          * so bdget() can't fail.
1959          */
1960         bdget(pd->bdev->bd_dev);
1961         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1962                 goto out;
1963
1964         if ((ret = pkt_get_last_written(pd, &lba))) {
1965                 printk("pktcdvd: pkt_get_last_written failed\n");
1966                 goto out_putdev;
1967         }
1968
1969         set_capacity(pd->disk, lba << 2);
1970         set_capacity(pd->bdev->bd_disk, lba << 2);
1971         bd_set_size(pd->bdev, (loff_t)lba << 11);
1972
1973         q = bdev_get_queue(pd->bdev);
1974         if (write) {
1975                 if ((ret = pkt_open_write(pd)))
1976                         goto out_putdev;
1977                 /*
1978                  * Some CDRW drives can not handle writes larger than one packet,
1979                  * even if the size is a multiple of the packet size.
1980                  */
1981                 spin_lock_irq(q->queue_lock);
1982                 blk_queue_max_sectors(q, pd->settings.size);
1983                 spin_unlock_irq(q->queue_lock);
1984                 set_bit(PACKET_WRITABLE, &pd->flags);
1985         } else {
1986                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1987                 clear_bit(PACKET_WRITABLE, &pd->flags);
1988         }
1989
1990         if ((ret = pkt_set_segment_merging(pd, q)))
1991                 goto out_putdev;
1992
1993         if (write)
1994                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1995
1996         return 0;
1997
1998 out_putdev:
1999         blkdev_put(pd->bdev);
2000 out:
2001         return ret;
2002 }
2003
2004 /*
2005  * called when the device is closed. makes sure that the device flushes
2006  * the internal cache before we close.
2007  */
2008 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2009 {
2010         if (flush && pkt_flush_cache(pd))
2011                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
2012
2013         pkt_lock_door(pd, 0);
2014
2015         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2016         blkdev_put(pd->bdev);
2017 }
2018
2019 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2020 {
2021         if (dev_minor >= MAX_WRITERS)
2022                 return NULL;
2023         return pkt_devs[dev_minor];
2024 }
2025
2026 static int pkt_open(struct inode *inode, struct file *file)
2027 {
2028         struct pktcdvd_device *pd = NULL;
2029         int ret;
2030
2031         VPRINTK("pktcdvd: entering open\n");
2032
2033         down(&ctl_mutex);
2034         pd = pkt_find_dev_from_minor(iminor(inode));
2035         if (!pd) {
2036                 ret = -ENODEV;
2037                 goto out;
2038         }
2039         BUG_ON(pd->refcnt < 0);
2040
2041         pd->refcnt++;
2042         if (pd->refcnt > 1) {
2043                 if ((file->f_mode & FMODE_WRITE) &&
2044                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2045                         ret = -EBUSY;
2046                         goto out_dec;
2047                 }
2048         } else {
2049                 if (pkt_open_dev(pd, file->f_mode & FMODE_WRITE)) {
2050                         ret = -EIO;
2051                         goto out_dec;
2052                 }
2053                 /*
2054                  * needed here as well, since ext2 (among others) may change
2055                  * the blocksize at mount time
2056                  */
2057                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2058         }
2059
2060         up(&ctl_mutex);
2061         return 0;
2062
2063 out_dec:
2064         pd->refcnt--;
2065 out:
2066         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2067         up(&ctl_mutex);
2068         return ret;
2069 }
2070
2071 static int pkt_close(struct inode *inode, struct file *file)
2072 {
2073         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2074         int ret = 0;
2075
2076         down(&ctl_mutex);
2077         pd->refcnt--;
2078         BUG_ON(pd->refcnt < 0);
2079         if (pd->refcnt == 0) {
2080                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2081                 pkt_release_dev(pd, flush);
2082         }
2083         up(&ctl_mutex);
2084         return ret;
2085 }
2086
2087
2088 static void *psd_pool_alloc(unsigned int __nocast gfp_mask, void *data)
2089 {
2090         return kmalloc(sizeof(struct packet_stacked_data), gfp_mask);
2091 }
2092
2093 static void psd_pool_free(void *ptr, void *data)
2094 {
2095         kfree(ptr);
2096 }
2097
2098 static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int err)
2099 {
2100         struct packet_stacked_data *psd = bio->bi_private;
2101         struct pktcdvd_device *pd = psd->pd;
2102
2103         if (bio->bi_size)
2104                 return 1;
2105
2106         bio_put(bio);
2107         bio_endio(psd->bio, psd->bio->bi_size, err);
2108         mempool_free(psd, psd_pool);
2109         pkt_bio_finished(pd);
2110         return 0;
2111 }
2112
2113 static int pkt_make_request(request_queue_t *q, struct bio *bio)
2114 {
2115         struct pktcdvd_device *pd;
2116         char b[BDEVNAME_SIZE];
2117         sector_t zone;
2118         struct packet_data *pkt;
2119         int was_empty, blocked_bio;
2120         struct pkt_rb_node *node;
2121
2122         pd = q->queuedata;
2123         if (!pd) {
2124                 printk("pktcdvd: %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2125                 goto end_io;
2126         }
2127
2128         /*
2129          * Clone READ bios so we can have our own bi_end_io callback.
2130          */
2131         if (bio_data_dir(bio) == READ) {
2132                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2133                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2134
2135                 psd->pd = pd;
2136                 psd->bio = bio;
2137                 cloned_bio->bi_bdev = pd->bdev;
2138                 cloned_bio->bi_private = psd;
2139                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2140                 pd->stats.secs_r += bio->bi_size >> 9;
2141                 pkt_queue_bio(pd, cloned_bio);
2142                 return 0;
2143         }
2144
2145         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2146                 printk("pktcdvd: WRITE for ro device %s (%llu)\n",
2147                         pd->name, (unsigned long long)bio->bi_sector);
2148                 goto end_io;
2149         }
2150
2151         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2152                 printk("pktcdvd: wrong bio size\n");
2153                 goto end_io;
2154         }
2155
2156         blk_queue_bounce(q, &bio);
2157
2158         zone = ZONE(bio->bi_sector, pd);
2159         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2160                 (unsigned long long)bio->bi_sector,
2161                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2162
2163         /* Check if we have to split the bio */
2164         {
2165                 struct bio_pair *bp;
2166                 sector_t last_zone;
2167                 int first_sectors;
2168
2169                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2170                 if (last_zone != zone) {
2171                         BUG_ON(last_zone != zone + pd->settings.size);
2172                         first_sectors = last_zone - bio->bi_sector;
2173                         bp = bio_split(bio, bio_split_pool, first_sectors);
2174                         BUG_ON(!bp);
2175                         pkt_make_request(q, &bp->bio1);
2176                         pkt_make_request(q, &bp->bio2);
2177                         bio_pair_release(bp);
2178                         return 0;
2179                 }
2180         }
2181
2182         /*
2183          * If we find a matching packet in state WAITING or READ_WAIT, we can
2184          * just append this bio to that packet.
2185          */
2186         spin_lock(&pd->cdrw.active_list_lock);
2187         blocked_bio = 0;
2188         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2189                 if (pkt->sector == zone) {
2190                         spin_lock(&pkt->lock);
2191                         if ((pkt->state == PACKET_WAITING_STATE) ||
2192                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2193                                 pkt_add_list_last(bio, &pkt->orig_bios,
2194                                                   &pkt->orig_bios_tail);
2195                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2196                                 if ((pkt->write_size >= pkt->frames) &&
2197                                     (pkt->state == PACKET_WAITING_STATE)) {
2198                                         atomic_inc(&pkt->run_sm);
2199                                         wake_up(&pd->wqueue);
2200                                 }
2201                                 spin_unlock(&pkt->lock);
2202                                 spin_unlock(&pd->cdrw.active_list_lock);
2203                                 return 0;
2204                         } else {
2205                                 blocked_bio = 1;
2206                         }
2207                         spin_unlock(&pkt->lock);
2208                 }
2209         }
2210         spin_unlock(&pd->cdrw.active_list_lock);
2211
2212         /*
2213          * No matching packet found. Store the bio in the work queue.
2214          */
2215         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2216         BUG_ON(!node);
2217         node->bio = bio;
2218         spin_lock(&pd->lock);
2219         BUG_ON(pd->bio_queue_size < 0);
2220         was_empty = (pd->bio_queue_size == 0);
2221         pkt_rbtree_insert(pd, node);
2222         spin_unlock(&pd->lock);
2223
2224         /*
2225          * Wake up the worker thread.
2226          */
2227         atomic_set(&pd->scan_queue, 1);
2228         if (was_empty) {
2229                 /* This wake_up is required for correct operation */
2230                 wake_up(&pd->wqueue);
2231         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2232                 /*
2233                  * This wake up is not required for correct operation,
2234                  * but improves performance in some cases.
2235                  */
2236                 wake_up(&pd->wqueue);
2237         }
2238         return 0;
2239 end_io:
2240         bio_io_error(bio, bio->bi_size);
2241         return 0;
2242 }
2243
2244
2245
2246 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2247 {
2248         struct pktcdvd_device *pd = q->queuedata;
2249         sector_t zone = ZONE(bio->bi_sector, pd);
2250         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2251         int remaining = (pd->settings.size << 9) - used;
2252         int remaining2;
2253
2254         /*
2255          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2256          * boundary, pkt_make_request() will split the bio.
2257          */
2258         remaining2 = PAGE_SIZE - bio->bi_size;
2259         remaining = max(remaining, remaining2);
2260
2261         BUG_ON(remaining < 0);
2262         return remaining;
2263 }
2264
2265 static void pkt_init_queue(struct pktcdvd_device *pd)
2266 {
2267         request_queue_t *q = pd->disk->queue;
2268
2269         blk_queue_make_request(q, pkt_make_request);
2270         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2271         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2272         blk_queue_merge_bvec(q, pkt_merge_bvec);
2273         q->queuedata = pd;
2274 }
2275
2276 static int pkt_seq_show(struct seq_file *m, void *p)
2277 {
2278         struct pktcdvd_device *pd = m->private;
2279         char *msg;
2280         char bdev_buf[BDEVNAME_SIZE];
2281         int states[PACKET_NUM_STATES];
2282
2283         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2284                    bdevname(pd->bdev, bdev_buf));
2285
2286         seq_printf(m, "\nSettings:\n");
2287         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2288
2289         if (pd->settings.write_type == 0)
2290                 msg = "Packet";
2291         else
2292                 msg = "Unknown";
2293         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2294
2295         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2296         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2297
2298         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2299
2300         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2301                 msg = "Mode 1";
2302         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2303                 msg = "Mode 2";
2304         else
2305                 msg = "Unknown";
2306         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2307
2308         seq_printf(m, "\nStatistics:\n");
2309         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2310         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2311         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2312         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2313         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2314
2315         seq_printf(m, "\nMisc:\n");
2316         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2317         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2318         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2319         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2320         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2321         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2322
2323         seq_printf(m, "\nQueue state:\n");
2324         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2325         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2326         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2327
2328         pkt_count_states(pd, states);
2329         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2330                    states[0], states[1], states[2], states[3], states[4], states[5]);
2331
2332         return 0;
2333 }
2334
2335 static int pkt_seq_open(struct inode *inode, struct file *file)
2336 {
2337         return single_open(file, pkt_seq_show, PDE(inode)->data);
2338 }
2339
2340 static struct file_operations pkt_proc_fops = {
2341         .open   = pkt_seq_open,
2342         .read   = seq_read,
2343         .llseek = seq_lseek,
2344         .release = single_release
2345 };
2346
2347 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2348 {
2349         int i;
2350         int ret = 0;
2351         char b[BDEVNAME_SIZE];
2352         struct proc_dir_entry *proc;
2353         struct block_device *bdev;
2354
2355         if (pd->pkt_dev == dev) {
2356                 printk("pktcdvd: Recursive setup not allowed\n");
2357                 return -EBUSY;
2358         }
2359         for (i = 0; i < MAX_WRITERS; i++) {
2360                 struct pktcdvd_device *pd2 = pkt_devs[i];
2361                 if (!pd2)
2362                         continue;
2363                 if (pd2->bdev->bd_dev == dev) {
2364                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2365                         return -EBUSY;
2366                 }
2367                 if (pd2->pkt_dev == dev) {
2368                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2369                         return -EBUSY;
2370                 }
2371         }
2372
2373         bdev = bdget(dev);
2374         if (!bdev)
2375                 return -ENOMEM;
2376         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2377         if (ret)
2378                 return ret;
2379
2380         /* This is safe, since we have a reference from open(). */
2381         __module_get(THIS_MODULE);
2382
2383         if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2384                 printk("pktcdvd: not enough memory for buffers\n");
2385                 ret = -ENOMEM;
2386                 goto out_mem;
2387         }
2388
2389         pd->bdev = bdev;
2390         set_blocksize(bdev, CD_FRAMESIZE);
2391
2392         pkt_init_queue(pd);
2393
2394         atomic_set(&pd->cdrw.pending_bios, 0);
2395         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2396         if (IS_ERR(pd->cdrw.thread)) {
2397                 printk("pktcdvd: can't start kernel thread\n");
2398                 ret = -ENOMEM;
2399                 goto out_thread;
2400         }
2401
2402         proc = create_proc_entry(pd->name, 0, pkt_proc);
2403         if (proc) {
2404                 proc->data = pd;
2405                 proc->proc_fops = &pkt_proc_fops;
2406         }
2407         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2408         return 0;
2409
2410 out_thread:
2411         pkt_shrink_pktlist(pd);
2412 out_mem:
2413         blkdev_put(bdev);
2414         /* This is safe: open() is still holding a reference. */
2415         module_put(THIS_MODULE);
2416         return ret;
2417 }
2418
2419 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2420 {
2421         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2422
2423         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2424         BUG_ON(!pd);
2425
2426         switch (cmd) {
2427         /*
2428          * forward selected CDROM ioctls to CD-ROM, for UDF
2429          */
2430         case CDROMMULTISESSION:
2431         case CDROMREADTOCENTRY:
2432         case CDROM_LAST_WRITTEN:
2433         case CDROM_SEND_PACKET:
2434         case SCSI_IOCTL_SEND_COMMAND:
2435                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2436
2437         case CDROMEJECT:
2438                 /*
2439                  * The door gets locked when the device is opened, so we
2440                  * have to unlock it or else the eject command fails.
2441                  */
2442                 pkt_lock_door(pd, 0);
2443                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2444
2445         default:
2446                 printk("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2447                 return -ENOTTY;
2448         }
2449
2450         return 0;
2451 }
2452
2453 static int pkt_media_changed(struct gendisk *disk)
2454 {
2455         struct pktcdvd_device *pd = disk->private_data;
2456         struct gendisk *attached_disk;
2457
2458         if (!pd)
2459                 return 0;
2460         if (!pd->bdev)
2461                 return 0;
2462         attached_disk = pd->bdev->bd_disk;
2463         if (!attached_disk)
2464                 return 0;
2465         return attached_disk->fops->media_changed(attached_disk);
2466 }
2467
2468 static struct block_device_operations pktcdvd_ops = {
2469         .owner =                THIS_MODULE,
2470         .open =                 pkt_open,
2471         .release =              pkt_close,
2472         .ioctl =                pkt_ioctl,
2473         .media_changed =        pkt_media_changed,
2474 };
2475
2476 /*
2477  * Set up mapping from pktcdvd device to CD-ROM device.
2478  */
2479 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2480 {
2481         int idx;
2482         int ret = -ENOMEM;
2483         struct pktcdvd_device *pd;
2484         struct gendisk *disk;
2485         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2486
2487         for (idx = 0; idx < MAX_WRITERS; idx++)
2488                 if (!pkt_devs[idx])
2489                         break;
2490         if (idx == MAX_WRITERS) {
2491                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2492                 return -EBUSY;
2493         }
2494
2495         pd = kmalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2496         if (!pd)
2497                 return ret;
2498         memset(pd, 0, sizeof(struct pktcdvd_device));
2499
2500         pd->rb_pool = mempool_create(PKT_RB_POOL_SIZE, pkt_rb_alloc, pkt_rb_free, NULL);
2501         if (!pd->rb_pool)
2502                 goto out_mem;
2503
2504         disk = alloc_disk(1);
2505         if (!disk)
2506                 goto out_mem;
2507         pd->disk = disk;
2508
2509         spin_lock_init(&pd->lock);
2510         spin_lock_init(&pd->iosched.lock);
2511         sprintf(pd->name, "pktcdvd%d", idx);
2512         init_waitqueue_head(&pd->wqueue);
2513         pd->bio_queue = RB_ROOT;
2514
2515         disk->major = pkt_major;
2516         disk->first_minor = idx;
2517         disk->fops = &pktcdvd_ops;
2518         disk->flags = GENHD_FL_REMOVABLE;
2519         sprintf(disk->disk_name, "pktcdvd%d", idx);
2520         disk->private_data = pd;
2521         disk->queue = blk_alloc_queue(GFP_KERNEL);
2522         if (!disk->queue)
2523                 goto out_mem2;
2524
2525         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2526         ret = pkt_new_dev(pd, dev);
2527         if (ret)
2528                 goto out_new_dev;
2529
2530         add_disk(disk);
2531         pkt_devs[idx] = pd;
2532         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2533         return 0;
2534
2535 out_new_dev:
2536         blk_put_queue(disk->queue);
2537 out_mem2:
2538         put_disk(disk);
2539 out_mem:
2540         if (pd->rb_pool)
2541                 mempool_destroy(pd->rb_pool);
2542         kfree(pd);
2543         return ret;
2544 }
2545
2546 /*
2547  * Tear down mapping from pktcdvd device to CD-ROM device.
2548  */
2549 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2550 {
2551         struct pktcdvd_device *pd;
2552         int idx;
2553         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2554
2555         for (idx = 0; idx < MAX_WRITERS; idx++) {
2556                 pd = pkt_devs[idx];
2557                 if (pd && (pd->pkt_dev == pkt_dev))
2558                         break;
2559         }
2560         if (idx == MAX_WRITERS) {
2561                 DPRINTK("pktcdvd: dev not setup\n");
2562                 return -ENXIO;
2563         }
2564
2565         if (pd->refcnt > 0)
2566                 return -EBUSY;
2567
2568         if (!IS_ERR(pd->cdrw.thread))
2569                 kthread_stop(pd->cdrw.thread);
2570
2571         blkdev_put(pd->bdev);
2572
2573         pkt_shrink_pktlist(pd);
2574
2575         remove_proc_entry(pd->name, pkt_proc);
2576         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2577
2578         del_gendisk(pd->disk);
2579         blk_put_queue(pd->disk->queue);
2580         put_disk(pd->disk);
2581
2582         pkt_devs[idx] = NULL;
2583         mempool_destroy(pd->rb_pool);
2584         kfree(pd);
2585
2586         /* This is safe: open() is still holding a reference. */
2587         module_put(THIS_MODULE);
2588         return 0;
2589 }
2590
2591 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2592 {
2593         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2594         if (pd) {
2595                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2596                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2597         } else {
2598                 ctrl_cmd->dev = 0;
2599                 ctrl_cmd->pkt_dev = 0;
2600         }
2601         ctrl_cmd->num_devices = MAX_WRITERS;
2602 }
2603
2604 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2605 {
2606         void __user *argp = (void __user *)arg;
2607         struct pkt_ctrl_command ctrl_cmd;
2608         int ret = 0;
2609
2610         if (cmd != PACKET_CTRL_CMD)
2611                 return -ENOTTY;
2612
2613         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2614                 return -EFAULT;
2615
2616         switch (ctrl_cmd.command) {
2617         case PKT_CTRL_CMD_SETUP:
2618                 if (!capable(CAP_SYS_ADMIN))
2619                         return -EPERM;
2620                 down(&ctl_mutex);
2621                 ret = pkt_setup_dev(&ctrl_cmd);
2622                 up(&ctl_mutex);
2623                 break;
2624         case PKT_CTRL_CMD_TEARDOWN:
2625                 if (!capable(CAP_SYS_ADMIN))
2626                         return -EPERM;
2627                 down(&ctl_mutex);
2628                 ret = pkt_remove_dev(&ctrl_cmd);
2629                 up(&ctl_mutex);
2630                 break;
2631         case PKT_CTRL_CMD_STATUS:
2632                 down(&ctl_mutex);
2633                 pkt_get_status(&ctrl_cmd);
2634                 up(&ctl_mutex);
2635                 break;
2636         default:
2637                 return -ENOTTY;
2638         }
2639
2640         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2641                 return -EFAULT;
2642         return ret;
2643 }
2644
2645
2646 static struct file_operations pkt_ctl_fops = {
2647         .ioctl   = pkt_ctl_ioctl,
2648         .owner   = THIS_MODULE,
2649 };
2650
2651 static struct miscdevice pkt_misc = {
2652         .minor          = MISC_DYNAMIC_MINOR,
2653         .name           = "pktcdvd",
2654         .devfs_name     = "pktcdvd/control",
2655         .fops           = &pkt_ctl_fops
2656 };
2657
2658 static int __init pkt_init(void)
2659 {
2660         int ret;
2661
2662         psd_pool = mempool_create(PSD_POOL_SIZE, psd_pool_alloc, psd_pool_free, NULL);
2663         if (!psd_pool)
2664                 return -ENOMEM;
2665
2666         ret = register_blkdev(pkt_major, "pktcdvd");
2667         if (ret < 0) {
2668                 printk("pktcdvd: Unable to register block device\n");
2669                 goto out2;
2670         }
2671         if (!pkt_major)
2672                 pkt_major = ret;
2673
2674         ret = misc_register(&pkt_misc);
2675         if (ret) {
2676                 printk("pktcdvd: Unable to register misc device\n");
2677                 goto out;
2678         }
2679
2680         init_MUTEX(&ctl_mutex);
2681
2682         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2683
2684         DPRINTK("pktcdvd: %s\n", VERSION_CODE);
2685         return 0;
2686
2687 out:
2688         unregister_blkdev(pkt_major, "pktcdvd");
2689 out2:
2690         mempool_destroy(psd_pool);
2691         return ret;
2692 }
2693
2694 static void __exit pkt_exit(void)
2695 {
2696         remove_proc_entry("pktcdvd", proc_root_driver);
2697         misc_deregister(&pkt_misc);
2698         unregister_blkdev(pkt_major, "pktcdvd");
2699         mempool_destroy(psd_pool);
2700 }
2701
2702 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2703 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2704 MODULE_LICENSE("GPL");
2705
2706 module_init(pkt_init);
2707 module_exit(pkt_exit);