drivers/scsi/sr.c

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This source file includes following definitions.
sr_runtime_suspend
scsi_cd_get
scsi_cd_put
sr_get_events
sr_check_events
sr_done
sr_init_command
sr_block_open
sr_block_release
sr_block_ioctl
sr_block_check_events
sr_block_revalidate_disk
sr_open
sr_release
sr_probe
get_sectorsize
get_capabilities
sr_packet
sr_kref_release
sr_remove
init_sr
exit_sr
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  sr.c Copyright (C) 1992 David Giller
   4  *           Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
   5  *
   6  *  adapted from:
   7  *      sd.c Copyright (C) 1992 Drew Eckhardt
   8  *      Linux scsi disk driver by
   9  *              Drew Eckhardt <drew@colorado.edu>
  10  *
  11  *      Modified by Eric Youngdale ericy@andante.org to
  12  *      add scatter-gather, multiple outstanding request, and other
  13  *      enhancements.
  14  *
  15  *      Modified by Eric Youngdale eric@andante.org to support loadable
  16  *      low-level scsi drivers.
  17  *
  18  *      Modified by Thomas Quinot thomas@melchior.cuivre.fdn.fr to
  19  *      provide auto-eject.
  20  *
  21  *      Modified by Gerd Knorr <kraxel@cs.tu-berlin.de> to support the
  22  *      generic cdrom interface
  23  *
  24  *      Modified by Jens Axboe <axboe@suse.de> - Uniform sr_packet()
  25  *      interface, capabilities probe additions, ioctl cleanups, etc.
  26  *
  27  *      Modified by Richard Gooch <rgooch@atnf.csiro.au> to support devfs
  28  *
  29  *      Modified by Jens Axboe <axboe@suse.de> - support DVD-RAM
  30  *      transparently and lose the GHOST hack
  31  *
  32  *      Modified by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  33  *      check resource allocation in sr_init and some cleanups
  34  */
  35 
  36 #include <linux/module.h>
  37 #include <linux/fs.h>
  38 #include <linux/kernel.h>
  39 #include <linux/mm.h>
  40 #include <linux/bio.h>
  41 #include <linux/string.h>
  42 #include <linux/errno.h>
  43 #include <linux/cdrom.h>
  44 #include <linux/interrupt.h>
  45 #include <linux/init.h>
  46 #include <linux/blkdev.h>
  47 #include <linux/blk-pm.h>
  48 #include <linux/mutex.h>
  49 #include <linux/slab.h>
  50 #include <linux/pm_runtime.h>
  51 #include <linux/uaccess.h>
  52 
  53 #include <scsi/scsi.h>
  54 #include <scsi/scsi_dbg.h>
  55 #include <scsi/scsi_device.h>
  56 #include <scsi/scsi_driver.h>
  57 #include <scsi/scsi_cmnd.h>
  58 #include <scsi/scsi_eh.h>
  59 #include <scsi/scsi_host.h>
  60 #include <scsi/scsi_ioctl.h>    /* For the door lock/unlock commands */
  61 
  62 #include "scsi_logging.h"
  63 #include "sr.h"
  64 
  65 
  66 MODULE_DESCRIPTION("SCSI cdrom (sr) driver");
  67 MODULE_LICENSE("GPL");
  68 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_CDROM_MAJOR);
  69 MODULE_ALIAS_SCSI_DEVICE(TYPE_ROM);
  70 MODULE_ALIAS_SCSI_DEVICE(TYPE_WORM);
  71 
  72 #define SR_DISKS        256
  73 
  74 #define SR_CAPABILITIES \
  75         (CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|CDC_SELECT_SPEED| \
  76          CDC_SELECT_DISC|CDC_MULTI_SESSION|CDC_MCN|CDC_MEDIA_CHANGED| \
  77          CDC_PLAY_AUDIO|CDC_RESET|CDC_DRIVE_STATUS| \
  78          CDC_CD_R|CDC_CD_RW|CDC_DVD|CDC_DVD_R|CDC_DVD_RAM|CDC_GENERIC_PACKET| \
  79          CDC_MRW|CDC_MRW_W|CDC_RAM)
  80 
  81 static DEFINE_MUTEX(sr_mutex);
  82 static int sr_probe(struct device *);
  83 static int sr_remove(struct device *);
  84 static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt);
  85 static int sr_done(struct scsi_cmnd *);
  86 static int sr_runtime_suspend(struct device *dev);
  87 
  88 static const struct dev_pm_ops sr_pm_ops = {
  89         .runtime_suspend        = sr_runtime_suspend,
  90 };
  91 
  92 static struct scsi_driver sr_template = {
  93         .gendrv = {
  94                 .name           = "sr",
  95                 .owner          = THIS_MODULE,
  96                 .probe          = sr_probe,
  97                 .remove         = sr_remove,
  98                 .pm             = &sr_pm_ops,
  99         },
 100         .init_command           = sr_init_command,
 101         .done                   = sr_done,
 102 };
 103 
 104 static unsigned long sr_index_bits[SR_DISKS / BITS_PER_LONG];
 105 static DEFINE_SPINLOCK(sr_index_lock);
 106 
 107 /* This semaphore is used to mediate the 0->1 reference get in the
 108  * face of object destruction (i.e. we can't allow a get on an
 109  * object after last put) */
 110 static DEFINE_MUTEX(sr_ref_mutex);
 111 
 112 static int sr_open(struct cdrom_device_info *, int);
 113 static void sr_release(struct cdrom_device_info *);
 114 
 115 static void get_sectorsize(struct scsi_cd *);
 116 static void get_capabilities(struct scsi_cd *);
 117 
 118 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
 119                                     unsigned int clearing, int slot);
 120 static int sr_packet(struct cdrom_device_info *, struct packet_command *);
 121 
 122 static const struct cdrom_device_ops sr_dops = {
 123         .open                   = sr_open,
 124         .release                = sr_release,
 125         .drive_status           = sr_drive_status,
 126         .check_events           = sr_check_events,
 127         .tray_move              = sr_tray_move,
 128         .lock_door              = sr_lock_door,
 129         .select_speed           = sr_select_speed,
 130         .get_last_session       = sr_get_last_session,
 131         .get_mcn                = sr_get_mcn,
 132         .reset                  = sr_reset,
 133         .audio_ioctl            = sr_audio_ioctl,
 134         .capability             = SR_CAPABILITIES,
 135         .generic_packet         = sr_packet,
 136 };
 137 
 138 static void sr_kref_release(struct kref *kref);
 139 
 140 static inline struct scsi_cd *scsi_cd(struct gendisk *disk)
 141 {
 142         return container_of(disk->private_data, struct scsi_cd, driver);
 143 }
 144 
 145 static int sr_runtime_suspend(struct device *dev)
 146 {
 147         struct scsi_cd *cd = dev_get_drvdata(dev);
 148 
 149         if (!cd)        /* E.g.: runtime suspend following sr_remove() */
 150                 return 0;
 151 
 152         if (cd->media_present)
 153                 return -EBUSY;
 154         else
 155                 return 0;
 156 }
 157 
 158 /*
 159  * The get and put routines for the struct scsi_cd.  Note this entity
 160  * has a scsi_device pointer and owns a reference to this.
 161  */
 162 static inline struct scsi_cd *scsi_cd_get(struct gendisk *disk)
 163 {
 164         struct scsi_cd *cd = NULL;
 165 
 166         mutex_lock(&sr_ref_mutex);
 167         if (disk->private_data == NULL)
 168                 goto out;
 169         cd = scsi_cd(disk);
 170         kref_get(&cd->kref);
 171         if (scsi_device_get(cd->device)) {
 172                 kref_put(&cd->kref, sr_kref_release);
 173                 cd = NULL;
 174         }
 175  out:
 176         mutex_unlock(&sr_ref_mutex);
 177         return cd;
 178 }
 179 
 180 static void scsi_cd_put(struct scsi_cd *cd)
 181 {
 182         struct scsi_device *sdev = cd->device;
 183 
 184         mutex_lock(&sr_ref_mutex);
 185         kref_put(&cd->kref, sr_kref_release);
 186         scsi_device_put(sdev);
 187         mutex_unlock(&sr_ref_mutex);
 188 }
 189 
 190 static unsigned int sr_get_events(struct scsi_device *sdev)
 191 {
 192         u8 buf[8];
 193         u8 cmd[] = { GET_EVENT_STATUS_NOTIFICATION,
 194                      1,                 /* polled */
 195                      0, 0,              /* reserved */
 196                      1 << 4,            /* notification class: media */
 197                      0, 0,              /* reserved */
 198                      0, sizeof(buf),    /* allocation length */
 199                      0,                 /* control */
 200         };
 201         struct event_header *eh = (void *)buf;
 202         struct media_event_desc *med = (void *)(buf + 4);
 203         struct scsi_sense_hdr sshdr;
 204         int result;
 205 
 206         result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, sizeof(buf),
 207                                   &sshdr, SR_TIMEOUT, MAX_RETRIES, NULL);
 208         if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION)
 209                 return DISK_EVENT_MEDIA_CHANGE;
 210 
 211         if (result || be16_to_cpu(eh->data_len) < sizeof(*med))
 212                 return 0;
 213 
 214         if (eh->nea || eh->notification_class != 0x4)
 215                 return 0;
 216 
 217         if (med->media_event_code == 1)
 218                 return DISK_EVENT_EJECT_REQUEST;
 219         else if (med->media_event_code == 2)
 220                 return DISK_EVENT_MEDIA_CHANGE;
 221         return 0;
 222 }
 223 
 224 /*
 225  * This function checks to see if the media has been changed or eject
 226  * button has been pressed.  It is possible that we have already
 227  * sensed a change, or the drive may have sensed one and not yet
 228  * reported it.  The past events are accumulated in sdev->changed and
 229  * returned together with the current state.
 230  */
 231 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
 232                                     unsigned int clearing, int slot)
 233 {
 234         struct scsi_cd *cd = cdi->handle;
 235         bool last_present;
 236         struct scsi_sense_hdr sshdr;
 237         unsigned int events;
 238         int ret;
 239 
 240         /* no changer support */
 241         if (CDSL_CURRENT != slot)
 242                 return 0;
 243 
 244         events = sr_get_events(cd->device);
 245         cd->get_event_changed |= events & DISK_EVENT_MEDIA_CHANGE;
 246 
 247         /*
 248          * If earlier GET_EVENT_STATUS_NOTIFICATION and TUR did not agree
 249          * for several times in a row.  We rely on TUR only for this likely
 250          * broken device, to prevent generating incorrect media changed
 251          * events for every open().
 252          */
 253         if (cd->ignore_get_event) {
 254                 events &= ~DISK_EVENT_MEDIA_CHANGE;
 255                 goto do_tur;
 256         }
 257 
 258         /*
 259          * GET_EVENT_STATUS_NOTIFICATION is enough unless MEDIA_CHANGE
 260          * is being cleared.  Note that there are devices which hang
 261          * if asked to execute TUR repeatedly.
 262          */
 263         if (cd->device->changed) {
 264                 events |= DISK_EVENT_MEDIA_CHANGE;
 265                 cd->device->changed = 0;
 266                 cd->tur_changed = true;
 267         }
 268 
 269         if (!(clearing & DISK_EVENT_MEDIA_CHANGE))
 270                 return events;
 271 do_tur:
 272         /* let's see whether the media is there with TUR */
 273         last_present = cd->media_present;
 274         ret = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
 275 
 276         /*
 277          * Media is considered to be present if TUR succeeds or fails with
 278          * sense data indicating something other than media-not-present
 279          * (ASC 0x3a).
 280          */
 281         cd->media_present = scsi_status_is_good(ret) ||
 282                 (scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a);
 283 
 284         if (last_present != cd->media_present)
 285                 cd->device->changed = 1;
 286 
 287         if (cd->device->changed) {
 288                 events |= DISK_EVENT_MEDIA_CHANGE;
 289                 cd->device->changed = 0;
 290                 cd->tur_changed = true;
 291         }
 292 
 293         if (cd->ignore_get_event)
 294                 return events;
 295 
 296         /* check whether GET_EVENT is reporting spurious MEDIA_CHANGE */
 297         if (!cd->tur_changed) {
 298                 if (cd->get_event_changed) {
 299                         if (cd->tur_mismatch++ > 8) {
 300                                 sr_printk(KERN_WARNING, cd,
 301                                           "GET_EVENT and TUR disagree continuously, suppress GET_EVENT events\n");
 302                                 cd->ignore_get_event = true;
 303                         }
 304                 } else {
 305                         cd->tur_mismatch = 0;
 306                 }
 307         }
 308         cd->tur_changed = false;
 309         cd->get_event_changed = false;
 310 
 311         return events;
 312 }
 313 
 314 /*
 315  * sr_done is the interrupt routine for the device driver.
 316  *
 317  * It will be notified on the end of a SCSI read / write, and will take one
 318  * of several actions based on success or failure.
 319  */
 320 static int sr_done(struct scsi_cmnd *SCpnt)
 321 {
 322         int result = SCpnt->result;
 323         int this_count = scsi_bufflen(SCpnt);
 324         int good_bytes = (result == 0 ? this_count : 0);
 325         int block_sectors = 0;
 326         long error_sector;
 327         struct scsi_cd *cd = scsi_cd(SCpnt->request->rq_disk);
 328 
 329 #ifdef DEBUG
 330         scmd_printk(KERN_INFO, SCpnt, "done: %x\n", result);
 331 #endif
 332 
 333         /*
 334          * Handle MEDIUM ERRORs or VOLUME OVERFLOWs that indicate partial
 335          * success.  Since this is a relatively rare error condition, no
 336          * care is taken to avoid unnecessary additional work such as
 337          * memcpy's that could be avoided.
 338          */
 339         if (driver_byte(result) != 0 &&         /* An error occurred */
 340             (SCpnt->sense_buffer[0] & 0x7f) == 0x70) { /* Sense current */
 341                 switch (SCpnt->sense_buffer[2]) {
 342                 case MEDIUM_ERROR:
 343                 case VOLUME_OVERFLOW:
 344                 case ILLEGAL_REQUEST:
 345                         if (!(SCpnt->sense_buffer[0] & 0x90))
 346                                 break;
 347                         error_sector = (SCpnt->sense_buffer[3] << 24) |
 348                                 (SCpnt->sense_buffer[4] << 16) |
 349                                 (SCpnt->sense_buffer[5] << 8) |
 350                                 SCpnt->sense_buffer[6];
 351                         if (SCpnt->request->bio != NULL)
 352                                 block_sectors =
 353                                         bio_sectors(SCpnt->request->bio);
 354                         if (block_sectors < 4)
 355                                 block_sectors = 4;
 356                         if (cd->device->sector_size == 2048)
 357                                 error_sector <<= 2;
 358                         error_sector &= ~(block_sectors - 1);
 359                         good_bytes = (error_sector -
 360                                       blk_rq_pos(SCpnt->request)) << 9;
 361                         if (good_bytes < 0 || good_bytes >= this_count)
 362                                 good_bytes = 0;
 363                         /*
 364                          * The SCSI specification allows for the value
 365                          * returned by READ CAPACITY to be up to 75 2K
 366                          * sectors past the last readable block.
 367                          * Therefore, if we hit a medium error within the
 368                          * last 75 2K sectors, we decrease the saved size
 369                          * value.
 370                          */
 371                         if (error_sector < get_capacity(cd->disk) &&
 372                             cd->capacity - error_sector < 4 * 75)
 373                                 set_capacity(cd->disk, error_sector);
 374                         break;
 375 
 376                 case RECOVERED_ERROR:
 377                         good_bytes = this_count;
 378                         break;
 379 
 380                 default:
 381                         break;
 382                 }
 383         }
 384 
 385         return good_bytes;
 386 }
 387 
 388 static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
 389 {
 390         int block = 0, this_count, s_size;
 391         struct scsi_cd *cd;
 392         struct request *rq = SCpnt->request;
 393         blk_status_t ret;
 394 
 395         ret = scsi_init_io(SCpnt);
 396         if (ret != BLK_STS_OK)
 397                 goto out;
 398         cd = scsi_cd(rq->rq_disk);
 399 
 400         /* from here on until we're complete, any goto out
 401          * is used for a killable error condition */
 402         ret = BLK_STS_IOERR;
 403 
 404         SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
 405                 "Doing sr request, block = %d\n", block));
 406 
 407         if (!cd->device || !scsi_device_online(cd->device)) {
 408                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 409                         "Finishing %u sectors\n", blk_rq_sectors(rq)));
 410                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 411                         "Retry with 0x%p\n", SCpnt));
 412                 goto out;
 413         }
 414 
 415         if (cd->device->changed) {
 416                 /*
 417                  * quietly refuse to do anything to a changed disc until the
 418                  * changed bit has been reset
 419                  */
 420                 goto out;
 421         }
 422 
 423         /*
 424          * we do lazy blocksize switching (when reading XA sectors,
 425          * see CDROMREADMODE2 ioctl) 
 426          */
 427         s_size = cd->device->sector_size;
 428         if (s_size > 2048) {
 429                 if (!in_interrupt())
 430                         sr_set_blocklength(cd, 2048);
 431                 else
 432                         scmd_printk(KERN_INFO, SCpnt,
 433                                     "can't switch blocksize: in interrupt\n");
 434         }
 435 
 436         if (s_size != 512 && s_size != 1024 && s_size != 2048) {
 437                 scmd_printk(KERN_ERR, SCpnt, "bad sector size %d\n", s_size);
 438                 goto out;
 439         }
 440 
 441         switch (req_op(rq)) {
 442         case REQ_OP_WRITE:
 443                 if (!cd->writeable)
 444                         goto out;
 445                 SCpnt->cmnd[0] = WRITE_10;
 446                 cd->cdi.media_written = 1;
 447                 break;
 448         case REQ_OP_READ:
 449                 SCpnt->cmnd[0] = READ_10;
 450                 break;
 451         default:
 452                 blk_dump_rq_flags(rq, "Unknown sr command");
 453                 goto out;
 454         }
 455 
 456         {
 457                 struct scatterlist *sg;
 458                 int i, size = 0, sg_count = scsi_sg_count(SCpnt);
 459 
 460                 scsi_for_each_sg(SCpnt, sg, sg_count, i)
 461                         size += sg->length;
 462 
 463                 if (size != scsi_bufflen(SCpnt)) {
 464                         scmd_printk(KERN_ERR, SCpnt,
 465                                 "mismatch count %d, bytes %d\n",
 466                                 size, scsi_bufflen(SCpnt));
 467                         if (scsi_bufflen(SCpnt) > size)
 468                                 SCpnt->sdb.length = size;
 469                 }
 470         }
 471 
 472         /*
 473          * request doesn't start on hw block boundary, add scatter pads
 474          */
 475         if (((unsigned int)blk_rq_pos(rq) % (s_size >> 9)) ||
 476             (scsi_bufflen(SCpnt) % s_size)) {
 477                 scmd_printk(KERN_NOTICE, SCpnt, "unaligned transfer\n");
 478                 goto out;
 479         }
 480 
 481         this_count = (scsi_bufflen(SCpnt) >> 9) / (s_size >> 9);
 482 
 483 
 484         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 485                                         "%s %d/%u 512 byte blocks.\n",
 486                                         (rq_data_dir(rq) == WRITE) ?
 487                                         "writing" : "reading",
 488                                         this_count, blk_rq_sectors(rq)));
 489 
 490         SCpnt->cmnd[1] = 0;
 491         block = (unsigned int)blk_rq_pos(rq) / (s_size >> 9);
 492 
 493         if (this_count > 0xffff) {
 494                 this_count = 0xffff;
 495                 SCpnt->sdb.length = this_count * s_size;
 496         }
 497 
 498         SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
 499         SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
 500         SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
 501         SCpnt->cmnd[5] = (unsigned char) block & 0xff;
 502         SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
 503         SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
 504         SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
 505 
 506         /*
 507          * We shouldn't disconnect in the middle of a sector, so with a dumb
 508          * host adapter, it's safe to assume that we can at least transfer
 509          * this many bytes between each connect / disconnect.
 510          */
 511         SCpnt->transfersize = cd->device->sector_size;
 512         SCpnt->underflow = this_count << 9;
 513         SCpnt->allowed = MAX_RETRIES;
 514 
 515         /*
 516          * This indicates that the command is ready from our end to be
 517          * queued.
 518          */
 519         ret = BLK_STS_OK;
 520  out:
 521         return ret;
 522 }
 523 
 524 static int sr_block_open(struct block_device *bdev, fmode_t mode)
 525 {
 526         struct scsi_cd *cd;
 527         struct scsi_device *sdev;
 528         int ret = -ENXIO;
 529 
 530         cd = scsi_cd_get(bdev->bd_disk);
 531         if (!cd)
 532                 goto out;
 533 
 534         sdev = cd->device;
 535         scsi_autopm_get_device(sdev);
 536         check_disk_change(bdev);
 537 
 538         mutex_lock(&sr_mutex);
 539         ret = cdrom_open(&cd->cdi, bdev, mode);
 540         mutex_unlock(&sr_mutex);
 541 
 542         scsi_autopm_put_device(sdev);
 543         if (ret)
 544                 scsi_cd_put(cd);
 545 
 546 out:
 547         return ret;
 548 }
 549 
 550 static void sr_block_release(struct gendisk *disk, fmode_t mode)
 551 {
 552         struct scsi_cd *cd = scsi_cd(disk);
 553         mutex_lock(&sr_mutex);
 554         cdrom_release(&cd->cdi, mode);
 555         scsi_cd_put(cd);
 556         mutex_unlock(&sr_mutex);
 557 }
 558 
 559 static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 560                           unsigned long arg)
 561 {
 562         struct scsi_cd *cd = scsi_cd(bdev->bd_disk);
 563         struct scsi_device *sdev = cd->device;
 564         void __user *argp = (void __user *)arg;
 565         int ret;
 566 
 567         mutex_lock(&sr_mutex);
 568 
 569         ret = scsi_ioctl_block_when_processing_errors(sdev, cmd,
 570                         (mode & FMODE_NDELAY) != 0);
 571         if (ret)
 572                 goto out;
 573 
 574         scsi_autopm_get_device(sdev);
 575 
 576         /*
 577          * Send SCSI addressing ioctls directly to mid level, send other
 578          * ioctls to cdrom/block level.
 579          */
 580         switch (cmd) {
 581         case SCSI_IOCTL_GET_IDLUN:
 582         case SCSI_IOCTL_GET_BUS_NUMBER:
 583                 ret = scsi_ioctl(sdev, cmd, argp);
 584                 goto put;
 585         }
 586 
 587         ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, arg);
 588         if (ret != -ENOSYS)
 589                 goto put;
 590 
 591         ret = scsi_ioctl(sdev, cmd, argp);
 592 
 593 put:
 594         scsi_autopm_put_device(sdev);
 595 
 596 out:
 597         mutex_unlock(&sr_mutex);
 598         return ret;
 599 }
 600 
 601 static unsigned int sr_block_check_events(struct gendisk *disk,
 602                                           unsigned int clearing)
 603 {
 604         unsigned int ret = 0;
 605         struct scsi_cd *cd;
 606 
 607         cd = scsi_cd_get(disk);
 608         if (!cd)
 609                 return 0;
 610 
 611         if (!atomic_read(&cd->device->disk_events_disable_depth))
 612                 ret = cdrom_check_events(&cd->cdi, clearing);
 613 
 614         scsi_cd_put(cd);
 615         return ret;
 616 }
 617 
 618 static int sr_block_revalidate_disk(struct gendisk *disk)
 619 {
 620         struct scsi_sense_hdr sshdr;
 621         struct scsi_cd *cd;
 622 
 623         cd = scsi_cd_get(disk);
 624         if (!cd)
 625                 return -ENXIO;
 626 
 627         /* if the unit is not ready, nothing more to do */
 628         if (scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr))
 629                 goto out;
 630 
 631         sr_cd_check(&cd->cdi);
 632         get_sectorsize(cd);
 633 out:
 634         scsi_cd_put(cd);
 635         return 0;
 636 }
 637 
 638 static const struct block_device_operations sr_bdops =
 639 {
 640         .owner          = THIS_MODULE,
 641         .open           = sr_block_open,
 642         .release        = sr_block_release,
 643         .ioctl          = sr_block_ioctl,
 644         .check_events   = sr_block_check_events,
 645         .revalidate_disk = sr_block_revalidate_disk,
 646         /* 
 647          * No compat_ioctl for now because sr_block_ioctl never
 648          * seems to pass arbitrary ioctls down to host drivers.
 649          */
 650 };
 651 
 652 static int sr_open(struct cdrom_device_info *cdi, int purpose)
 653 {
 654         struct scsi_cd *cd = cdi->handle;
 655         struct scsi_device *sdev = cd->device;
 656         int retval;
 657 
 658         /*
 659          * If the device is in error recovery, wait until it is done.
 660          * If the device is offline, then disallow any access to it.
 661          */
 662         retval = -ENXIO;
 663         if (!scsi_block_when_processing_errors(sdev))
 664                 goto error_out;
 665 
 666         return 0;
 667 
 668 error_out:
 669         return retval;  
 670 }
 671 
 672 static void sr_release(struct cdrom_device_info *cdi)
 673 {
 674         struct scsi_cd *cd = cdi->handle;
 675 
 676         if (cd->device->sector_size > 2048)
 677                 sr_set_blocklength(cd, 2048);
 678 
 679 }
 680 
 681 static int sr_probe(struct device *dev)
 682 {
 683         struct scsi_device *sdev = to_scsi_device(dev);
 684         struct gendisk *disk;
 685         struct scsi_cd *cd;
 686         int minor, error;
 687 
 688         scsi_autopm_get_device(sdev);
 689         error = -ENODEV;
 690         if (sdev->type != TYPE_ROM && sdev->type != TYPE_WORM)
 691                 goto fail;
 692 
 693         error = -ENOMEM;
 694         cd = kzalloc(sizeof(*cd), GFP_KERNEL);
 695         if (!cd)
 696                 goto fail;
 697 
 698         kref_init(&cd->kref);
 699 
 700         disk = alloc_disk(1);
 701         if (!disk)
 702                 goto fail_free;
 703 
 704         spin_lock(&sr_index_lock);
 705         minor = find_first_zero_bit(sr_index_bits, SR_DISKS);
 706         if (minor == SR_DISKS) {
 707                 spin_unlock(&sr_index_lock);
 708                 error = -EBUSY;
 709                 goto fail_put;
 710         }
 711         __set_bit(minor, sr_index_bits);
 712         spin_unlock(&sr_index_lock);
 713 
 714         disk->major = SCSI_CDROM_MAJOR;
 715         disk->first_minor = minor;
 716         sprintf(disk->disk_name, "sr%d", minor);
 717         disk->fops = &sr_bdops;
 718         disk->flags = GENHD_FL_CD | GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE;
 719         disk->events = DISK_EVENT_MEDIA_CHANGE | DISK_EVENT_EJECT_REQUEST;
 720         disk->event_flags = DISK_EVENT_FLAG_POLL | DISK_EVENT_FLAG_UEVENT;
 721 
 722         blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT);
 723 
 724         cd->device = sdev;
 725         cd->disk = disk;
 726         cd->driver = &sr_template;
 727         cd->disk = disk;
 728         cd->capacity = 0x1fffff;
 729         cd->device->changed = 1;        /* force recheck CD type */
 730         cd->media_present = 1;
 731         cd->use = 1;
 732         cd->readcd_known = 0;
 733         cd->readcd_cdda = 0;
 734 
 735         cd->cdi.ops = &sr_dops;
 736         cd->cdi.handle = cd;
 737         cd->cdi.mask = 0;
 738         cd->cdi.capacity = 1;
 739         sprintf(cd->cdi.name, "sr%d", minor);
 740 
 741         sdev->sector_size = 2048;       /* A guess, just in case */
 742 
 743         /* FIXME: need to handle a get_capabilities failure properly ?? */
 744         get_capabilities(cd);
 745         sr_vendor_init(cd);
 746 
 747         set_capacity(disk, cd->capacity);
 748         disk->private_data = &cd->driver;
 749         disk->queue = sdev->request_queue;
 750         cd->cdi.disk = disk;
 751 
 752         if (register_cdrom(&cd->cdi))
 753                 goto fail_put;
 754 
 755         /*
 756          * Initialize block layer runtime PM stuffs before the
 757          * periodic event checking request gets started in add_disk.
 758          */
 759         blk_pm_runtime_init(sdev->request_queue, dev);
 760 
 761         dev_set_drvdata(dev, cd);
 762         disk->flags |= GENHD_FL_REMOVABLE;
 763         device_add_disk(&sdev->sdev_gendev, disk, NULL);
 764 
 765         sdev_printk(KERN_DEBUG, sdev,
 766                     "Attached scsi CD-ROM %s\n", cd->cdi.name);
 767         scsi_autopm_put_device(cd->device);
 768 
 769         return 0;
 770 
 771 fail_put:
 772         put_disk(disk);
 773 fail_free:
 774         kfree(cd);
 775 fail:
 776         scsi_autopm_put_device(sdev);
 777         return error;
 778 }
 779 
 780 
 781 static void get_sectorsize(struct scsi_cd *cd)
 782 {
 783         unsigned char cmd[10];
 784         unsigned char buffer[8];
 785         int the_result, retries = 3;
 786         int sector_size;
 787         struct request_queue *queue;
 788 
 789         do {
 790                 cmd[0] = READ_CAPACITY;
 791                 memset((void *) &cmd[1], 0, 9);
 792                 memset(buffer, 0, sizeof(buffer));
 793 
 794                 /* Do the command and wait.. */
 795                 the_result = scsi_execute_req(cd->device, cmd, DMA_FROM_DEVICE,
 796                                               buffer, sizeof(buffer), NULL,
 797                                               SR_TIMEOUT, MAX_RETRIES, NULL);
 798 
 799                 retries--;
 800 
 801         } while (the_result && retries);
 802 
 803 
 804         if (the_result) {
 805                 cd->capacity = 0x1fffff;
 806                 sector_size = 2048;     /* A guess, just in case */
 807         } else {
 808                 long last_written;
 809 
 810                 cd->capacity = 1 + ((buffer[0] << 24) | (buffer[1] << 16) |
 811                                     (buffer[2] << 8) | buffer[3]);
 812                 /*
 813                  * READ_CAPACITY doesn't return the correct size on
 814                  * certain UDF media.  If last_written is larger, use
 815                  * it instead.
 816                  *
 817                  * http://bugzilla.kernel.org/show_bug.cgi?id=9668
 818                  */
 819                 if (!cdrom_get_last_written(&cd->cdi, &last_written))
 820                         cd->capacity = max_t(long, cd->capacity, last_written);
 821 
 822                 sector_size = (buffer[4] << 24) |
 823                     (buffer[5] << 16) | (buffer[6] << 8) | buffer[7];
 824                 switch (sector_size) {
 825                         /*
 826                          * HP 4020i CD-Recorder reports 2340 byte sectors
 827                          * Philips CD-Writers report 2352 byte sectors
 828                          *
 829                          * Use 2k sectors for them..
 830                          */
 831                 case 0:
 832                 case 2340:
 833                 case 2352:
 834                         sector_size = 2048;
 835                         /* fall through */
 836                 case 2048:
 837                         cd->capacity *= 4;
 838                         /* fall through */
 839                 case 512:
 840                         break;
 841                 default:
 842                         sr_printk(KERN_INFO, cd,
 843                                   "unsupported sector size %d.", sector_size);
 844                         cd->capacity = 0;
 845                 }
 846 
 847                 cd->device->sector_size = sector_size;
 848 
 849                 /*
 850                  * Add this so that we have the ability to correctly gauge
 851                  * what the device is capable of.
 852                  */
 853                 set_capacity(cd->disk, cd->capacity);
 854         }
 855 
 856         queue = cd->device->request_queue;
 857         blk_queue_logical_block_size(queue, sector_size);
 858 
 859         return;
 860 }
 861 
 862 static void get_capabilities(struct scsi_cd *cd)
 863 {
 864         unsigned char *buffer;
 865         struct scsi_mode_data data;
 866         struct scsi_sense_hdr sshdr;
 867         unsigned int ms_len = 128;
 868         int rc, n;
 869 
 870         static const char *loadmech[] =
 871         {
 872                 "caddy",
 873                 "tray",
 874                 "pop-up",
 875                 "",
 876                 "changer",
 877                 "cartridge changer",
 878                 "",
 879                 ""
 880         };
 881 
 882 
 883         /* allocate transfer buffer */
 884         buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
 885         if (!buffer) {
 886                 sr_printk(KERN_ERR, cd, "out of memory.\n");
 887                 return;
 888         }
 889 
 890         /* eat unit attentions */
 891         scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
 892 
 893         /* ask for mode page 0x2a */
 894         rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, ms_len,
 895                              SR_TIMEOUT, 3, &data, NULL);
 896 
 897         if (!scsi_status_is_good(rc) || data.length > ms_len ||
 898             data.header_length + data.block_descriptor_length > data.length) {
 899                 /* failed, drive doesn't have capabilities mode page */
 900                 cd->cdi.speed = 1;
 901                 cd->cdi.mask |= (CDC_CD_R | CDC_CD_RW | CDC_DVD_R |
 902                                  CDC_DVD | CDC_DVD_RAM |
 903                                  CDC_SELECT_DISC | CDC_SELECT_SPEED |
 904                                  CDC_MRW | CDC_MRW_W | CDC_RAM);
 905                 kfree(buffer);
 906                 sr_printk(KERN_INFO, cd, "scsi-1 drive");
 907                 return;
 908         }
 909 
 910         n = data.header_length + data.block_descriptor_length;
 911         cd->cdi.speed = ((buffer[n + 8] << 8) + buffer[n + 9]) / 176;
 912         cd->readcd_known = 1;
 913         cd->readcd_cdda = buffer[n + 5] & 0x01;
 914         /* print some capability bits */
 915         sr_printk(KERN_INFO, cd,
 916                   "scsi3-mmc drive: %dx/%dx %s%s%s%s%s%s\n",
 917                   ((buffer[n + 14] << 8) + buffer[n + 15]) / 176,
 918                   cd->cdi.speed,
 919                   buffer[n + 3] & 0x01 ? "writer " : "", /* CD Writer */
 920                   buffer[n + 3] & 0x20 ? "dvd-ram " : "",
 921                   buffer[n + 2] & 0x02 ? "cd/rw " : "", /* can read rewriteable */
 922                   buffer[n + 4] & 0x20 ? "xa/form2 " : "",      /* can read xa/from2 */
 923                   buffer[n + 5] & 0x01 ? "cdda " : "", /* can read audio data */
 924                   loadmech[buffer[n + 6] >> 5]);
 925         if ((buffer[n + 6] >> 5) == 0)
 926                 /* caddy drives can't close tray... */
 927                 cd->cdi.mask |= CDC_CLOSE_TRAY;
 928         if ((buffer[n + 2] & 0x8) == 0)
 929                 /* not a DVD drive */
 930                 cd->cdi.mask |= CDC_DVD;
 931         if ((buffer[n + 3] & 0x20) == 0)
 932                 /* can't write DVD-RAM media */
 933                 cd->cdi.mask |= CDC_DVD_RAM;
 934         if ((buffer[n + 3] & 0x10) == 0)
 935                 /* can't write DVD-R media */
 936                 cd->cdi.mask |= CDC_DVD_R;
 937         if ((buffer[n + 3] & 0x2) == 0)
 938                 /* can't write CD-RW media */
 939                 cd->cdi.mask |= CDC_CD_RW;
 940         if ((buffer[n + 3] & 0x1) == 0)
 941                 /* can't write CD-R media */
 942                 cd->cdi.mask |= CDC_CD_R;
 943         if ((buffer[n + 6] & 0x8) == 0)
 944                 /* can't eject */
 945                 cd->cdi.mask |= CDC_OPEN_TRAY;
 946 
 947         if ((buffer[n + 6] >> 5) == mechtype_individual_changer ||
 948             (buffer[n + 6] >> 5) == mechtype_cartridge_changer)
 949                 cd->cdi.capacity =
 950                     cdrom_number_of_slots(&cd->cdi);
 951         if (cd->cdi.capacity <= 1)
 952                 /* not a changer */
 953                 cd->cdi.mask |= CDC_SELECT_DISC;
 954         /*else    I don't think it can close its tray
 955                 cd->cdi.mask |= CDC_CLOSE_TRAY; */
 956 
 957         /*
 958          * if DVD-RAM, MRW-W or CD-RW, we are randomly writable
 959          */
 960         if ((cd->cdi.mask & (CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) !=
 961                         (CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) {
 962                 cd->writeable = 1;
 963         }
 964 
 965         kfree(buffer);
 966 }
 967 
 968 /*
 969  * sr_packet() is the entry point for the generic commands generated
 970  * by the Uniform CD-ROM layer.
 971  */
 972 static int sr_packet(struct cdrom_device_info *cdi,
 973                 struct packet_command *cgc)
 974 {
 975         struct scsi_cd *cd = cdi->handle;
 976         struct scsi_device *sdev = cd->device;
 977 
 978         if (cgc->cmd[0] == GPCMD_READ_DISC_INFO && sdev->no_read_disc_info)
 979                 return -EDRIVE_CANT_DO_THIS;
 980 
 981         if (cgc->timeout <= 0)
 982                 cgc->timeout = IOCTL_TIMEOUT;
 983 
 984         sr_do_ioctl(cd, cgc);
 985 
 986         return cgc->stat;
 987 }
 988 
 989 /**
 990  *      sr_kref_release - Called to free the scsi_cd structure
 991  *      @kref: pointer to embedded kref
 992  *
 993  *      sr_ref_mutex must be held entering this routine.  Because it is
 994  *      called on last put, you should always use the scsi_cd_get()
 995  *      scsi_cd_put() helpers which manipulate the semaphore directly
 996  *      and never do a direct kref_put().
 997  **/
 998 static void sr_kref_release(struct kref *kref)
 999 {
1000         struct scsi_cd *cd = container_of(kref, struct scsi_cd, kref);
1001         struct gendisk *disk = cd->disk;
1002 
1003         spin_lock(&sr_index_lock);
1004         clear_bit(MINOR(disk_devt(disk)), sr_index_bits);
1005         spin_unlock(&sr_index_lock);
1006 
1007         unregister_cdrom(&cd->cdi);
1008 
1009         disk->private_data = NULL;
1010 
1011         put_disk(disk);
1012 
1013         kfree(cd);
1014 }
1015 
1016 static int sr_remove(struct device *dev)
1017 {
1018         struct scsi_cd *cd = dev_get_drvdata(dev);
1019 
1020         scsi_autopm_get_device(cd->device);
1021 
1022         del_gendisk(cd->disk);
1023         dev_set_drvdata(dev, NULL);
1024 
1025         mutex_lock(&sr_ref_mutex);
1026         kref_put(&cd->kref, sr_kref_release);
1027         mutex_unlock(&sr_ref_mutex);
1028 
1029         return 0;
1030 }
1031 
1032 static int __init init_sr(void)
1033 {
1034         int rc;
1035 
1036         rc = register_blkdev(SCSI_CDROM_MAJOR, "sr");
1037         if (rc)
1038                 return rc;
1039         rc = scsi_register_driver(&sr_template.gendrv);
1040         if (rc)
1041                 unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
1042 
1043         return rc;
1044 }
1045 
1046 static void __exit exit_sr(void)
1047 {
1048         scsi_unregister_driver(&sr_template.gendrv);
1049         unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
1050 }
1051 
1052 module_init(init_sr);
1053 module_exit(exit_sr);
1054 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/scsi/sr.c

DEFINITIONS
