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