drivers/scsi/sd.c

   1 /*
   2  *      sd.c Copyright (C) 1992 Drew Eckhardt
   3  *           Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
   4  *
   5  *      Linux scsi disk driver
   6  *              Initial versions: Drew Eckhardt
   7  *              Subsequent revisions: Eric Youngdale
   8  *      Modification history:
   9  *       - Drew Eckhardt <drew@colorado.edu> original
  10  *       - Eric Youngdale <eric@andante.org> add scatter-gather, multiple
  11  *         outstanding request, and other enhancements.
  12  *         Support loadable low-level scsi drivers.
  13  *       - Jirka Hanika <geo@ff.cuni.cz> support more scsi disks using
  14  *         eight major numbers.
  15  *       - Richard Gooch <rgooch@atnf.csiro.au> support devfs.
  16  *       - Torben Mathiasen <tmm@image.dk> Resource allocation fixes in
  17  *         sd_init and cleanups.
  18  *       - Alex Davis <letmein@erols.com> Fix problem where partition info
  19  *         not being read in sd_open. Fix problem where removable media
  20  *         could be ejected after sd_open.
  21  *       - Douglas Gilbert <dgilbert@interlog.com> cleanup for lk 2.5.x
  22  *       - Badari Pulavarty <pbadari@us.ibm.com>, Matthew Wilcox
  23  *         <willy@debian.org>, Kurt Garloff <garloff@suse.de>:
  24  *         Support 32k/1M disks.
  25  *
  26  *      Logging policy (needs CONFIG_SCSI_LOGGING defined):
  27  *       - setting up transfer: SCSI_LOG_HLQUEUE levels 1 and 2
  28  *       - end of transfer (bh + scsi_lib): SCSI_LOG_HLCOMPLETE level 1
  29  *       - entering sd_ioctl: SCSI_LOG_IOCTL level 1
  30  *       - entering other commands: SCSI_LOG_HLQUEUE level 3
  31  *      Note: when the logging level is set by the user, it must be greater
  32  *      than the level indicated above to trigger output.
  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/genhd.h>
  41 #include <linux/hdreg.h>
  42 #include <linux/errno.h>
  43 #include <linux/idr.h>
  44 #include <linux/interrupt.h>
  45 #include <linux/init.h>
  46 #include <linux/blkdev.h>
  47 #include <linux/blkpg.h>
  48 #include <linux/delay.h>
  49 #include <linux/mutex.h>
  50 #include <linux/string_helpers.h>
  51 #include <linux/async.h>
  52 #include <linux/slab.h>
  53 #include <asm/uaccess.h>
  54 #include <asm/unaligned.h>
  55
  56 #include <scsi/scsi.h>
  57 #include <scsi/scsi_cmnd.h>
  58 #include <scsi/scsi_dbg.h>
  59 #include <scsi/scsi_device.h>
  60 #include <scsi/scsi_driver.h>
  61 #include <scsi/scsi_eh.h>
  62 #include <scsi/scsi_host.h>
  63 #include <scsi/scsi_ioctl.h>
  64 #include <scsi/scsicam.h>
  65
  66 #include "sd.h"
  67 #include "scsi_logging.h"
  68
  69 MODULE_AUTHOR("Eric Youngdale");
  70 MODULE_DESCRIPTION("SCSI disk (sd) driver");
  71 MODULE_LICENSE("GPL");
  72
  73 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
  74 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
  75 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
  76 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
  77 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
  78 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
  79 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
  80 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
  81 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
  82 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
  83 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
  84 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
  85 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
  86 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
  87 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
  88 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
  89 MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
  90 MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
  91 MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
  92
  93 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
  94 #define SD_MINORS       16
  95 #else
  96 #define SD_MINORS       0
  97 #endif
  98
  99 static void sd_config_discard(struct scsi_disk *, unsigned int);
 100 static int  sd_revalidate_disk(struct gendisk *);
 101 static void sd_unlock_native_capacity(struct gendisk *disk);
 102 static int  sd_probe(struct device *);
 103 static int  sd_remove(struct device *);
 104 static void sd_shutdown(struct device *);
 105 static int sd_suspend(struct device *, pm_message_t state);
 106 static int sd_resume(struct device *);
 107 static void sd_rescan(struct device *);
 108 static int sd_done(struct scsi_cmnd *);
 109 static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
 110 static void scsi_disk_release(struct device *cdev);
 111 static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
 112 static void sd_print_result(struct scsi_disk *, int);
 113
 114 static DEFINE_SPINLOCK(sd_index_lock);
 115 static DEFINE_IDA(sd_index_ida);
 116
 117 /* This semaphore is used to mediate the 0->1 reference get in the
 118  * face of object destruction (i.e. we can't allow a get on an
 119  * object after last put) */
 120 static DEFINE_MUTEX(sd_ref_mutex);
 121
 122 static struct kmem_cache *sd_cdb_cache;
 123 static mempool_t *sd_cdb_pool;
 124
 125 static const char *sd_cache_types[] = {
 126         "write through", "none", "write back",
 127         "write back, no read (daft)"
 128 };
 129
 130 static ssize_t
 131 sd_store_cache_type(struct device *dev, struct device_attribute *attr,
 132                     const char *buf, size_t count)
 133 {
 134         int i, ct = -1, rcd, wce, sp;
 135         struct scsi_disk *sdkp = to_scsi_disk(dev);
 136         struct scsi_device *sdp = sdkp->device;
 137         char buffer[64];
 138         char *buffer_data;
 139         struct scsi_mode_data data;
 140         struct scsi_sense_hdr sshdr;
 141         static const char temp[] = "temporary ";
 142         int len;
 143
 144         if (sdp->type != TYPE_DISK)
 145                 /* no cache control on RBC devices; theoretically they
 146                  * can do it, but there's probably so many exceptions
 147                  * it's not worth the risk */
 148                 return -EINVAL;
 149
 150         if (strncmp(buf, temp, sizeof(temp) - 1) == 0) {
 151                 buf += sizeof(temp) - 1;
 152                 sdkp->cache_override = 1;
 153         } else {
 154                 sdkp->cache_override = 0;
 155         }
 156
 157         for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
 158                 len = strlen(sd_cache_types[i]);
 159                 if (strncmp(sd_cache_types[i], buf, len) == 0 &&
 160                     buf[len] == '\n') {
 161                         ct = i;
 162                         break;
 163                 }
 164         }
 165         if (ct < 0)
 166                 return -EINVAL;
 167         rcd = ct & 0x01 ? 1 : 0;
 168         wce = ct & 0x02 ? 1 : 0;
 169
 170         if (sdkp->cache_override) {
 171                 sdkp->WCE = wce;
 172                 sdkp->RCD = rcd;
 173                 return count;
 174         }
 175
 176         if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
 177                             SD_MAX_RETRIES, &data, NULL))
 178                 return -EINVAL;
 179         len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
 180                   data.block_descriptor_length);
 181         buffer_data = buffer + data.header_length +
 182                 data.block_descriptor_length;
 183         buffer_data[2] &= ~0x05;
 184         buffer_data[2] |= wce << 2 | rcd;
 185         sp = buffer_data[0] & 0x80 ? 1 : 0;
 186
 187         if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
 188                              SD_MAX_RETRIES, &data, &sshdr)) {
 189                 if (scsi_sense_valid(&sshdr))
 190                         sd_print_sense_hdr(sdkp, &sshdr);
 191                 return -EINVAL;
 192         }
 193         revalidate_disk(sdkp->disk);
 194         return count;
 195 }
 196
 197 static ssize_t
 198 sd_store_manage_start_stop(struct device *dev, struct device_attribute *attr,
 199                            const char *buf, size_t count)
 200 {
 201         struct scsi_disk *sdkp = to_scsi_disk(dev);
 202         struct scsi_device *sdp = sdkp->device;
 203
 204         if (!capable(CAP_SYS_ADMIN))
 205                 return -EACCES;
 206
 207         sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
 208
 209         return count;
 210 }
 211
 212 static ssize_t
 213 sd_store_allow_restart(struct device *dev, struct device_attribute *attr,
 214                        const char *buf, size_t count)
 215 {
 216         struct scsi_disk *sdkp = to_scsi_disk(dev);
 217         struct scsi_device *sdp = sdkp->device;
 218
 219         if (!capable(CAP_SYS_ADMIN))
 220                 return -EACCES;
 221
 222         if (sdp->type != TYPE_DISK)
 223                 return -EINVAL;
 224
 225         sdp->allow_restart = simple_strtoul(buf, NULL, 10);
 226
 227         return count;
 228 }
 229
 230 static ssize_t
 231 sd_show_cache_type(struct device *dev, struct device_attribute *attr,
 232                    char *buf)
 233 {
 234         struct scsi_disk *sdkp = to_scsi_disk(dev);
 235         int ct = sdkp->RCD + 2*sdkp->WCE;
 236
 237         return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
 238 }
 239
 240 static ssize_t
 241 sd_show_fua(struct device *dev, struct device_attribute *attr, char *buf)
 242 {
 243         struct scsi_disk *sdkp = to_scsi_disk(dev);
 244
 245         return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
 246 }
 247
 248 static ssize_t
 249 sd_show_manage_start_stop(struct device *dev, struct device_attribute *attr,
 250                           char *buf)
 251 {
 252         struct scsi_disk *sdkp = to_scsi_disk(dev);
 253         struct scsi_device *sdp = sdkp->device;
 254
 255         return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
 256 }
 257
 258 static ssize_t
 259 sd_show_allow_restart(struct device *dev, struct device_attribute *attr,
 260                       char *buf)
 261 {
 262         struct scsi_disk *sdkp = to_scsi_disk(dev);
 263
 264         return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
 265 }
 266
 267 static ssize_t
 268 sd_show_protection_type(struct device *dev, struct device_attribute *attr,
 269                         char *buf)
 270 {
 271         struct scsi_disk *sdkp = to_scsi_disk(dev);
 272
 273         return snprintf(buf, 20, "%u\n", sdkp->protection_type);
 274 }
 275
 276 static ssize_t
 277 sd_show_protection_mode(struct device *dev, struct device_attribute *attr,
 278                         char *buf)
 279 {
 280         struct scsi_disk *sdkp = to_scsi_disk(dev);
 281         struct scsi_device *sdp = sdkp->device;
 282         unsigned int dif, dix;
 283
 284         dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
 285         dix = scsi_host_dix_capable(sdp->host, sdkp->protection_type);
 286
 287         if (!dix && scsi_host_dix_capable(sdp->host, SD_DIF_TYPE0_PROTECTION)) {
 288                 dif = 0;
 289                 dix = 1;
 290         }
 291
 292         if (!dif && !dix)
 293                 return snprintf(buf, 20, "none\n");
 294
 295         return snprintf(buf, 20, "%s%u\n", dix ? "dix" : "dif", dif);
 296 }
 297
 298 static ssize_t
 299 sd_show_app_tag_own(struct device *dev, struct device_attribute *attr,
 300                     char *buf)
 301 {
 302         struct scsi_disk *sdkp = to_scsi_disk(dev);
 303
 304         return snprintf(buf, 20, "%u\n", sdkp->ATO);
 305 }
 306
 307 static ssize_t
 308 sd_show_thin_provisioning(struct device *dev, struct device_attribute *attr,
 309                           char *buf)
 310 {
 311         struct scsi_disk *sdkp = to_scsi_disk(dev);
 312
 313         return snprintf(buf, 20, "%u\n", sdkp->lbpme);
 314 }
 315
 316 static const char *lbp_mode[] = {
 317         [SD_LBP_FULL]           = "full",
 318         [SD_LBP_UNMAP]          = "unmap",
 319         [SD_LBP_WS16]           = "writesame_16",
 320         [SD_LBP_WS10]           = "writesame_10",
 321         [SD_LBP_ZERO]           = "writesame_zero",
 322         [SD_LBP_DISABLE]        = "disabled",
 323 };
 324
 325 static ssize_t
 326 sd_show_provisioning_mode(struct device *dev, struct device_attribute *attr,
 327                           char *buf)
 328 {
 329         struct scsi_disk *sdkp = to_scsi_disk(dev);
 330
 331         return snprintf(buf, 20, "%s\n", lbp_mode[sdkp->provisioning_mode]);
 332 }
 333
 334 static ssize_t
 335 sd_store_provisioning_mode(struct device *dev, struct device_attribute *attr,
 336                            const char *buf, size_t count)
 337 {
 338         struct scsi_disk *sdkp = to_scsi_disk(dev);
 339         struct scsi_device *sdp = sdkp->device;
 340
 341         if (!capable(CAP_SYS_ADMIN))
 342                 return -EACCES;
 343
 344         if (sdp->type != TYPE_DISK)
 345                 return -EINVAL;
 346
 347         if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
 348                 sd_config_discard(sdkp, SD_LBP_UNMAP);
 349         else if (!strncmp(buf, lbp_mode[SD_LBP_WS16], 20))
 350                 sd_config_discard(sdkp, SD_LBP_WS16);
 351         else if (!strncmp(buf, lbp_mode[SD_LBP_WS10], 20))
 352                 sd_config_discard(sdkp, SD_LBP_WS10);
 353         else if (!strncmp(buf, lbp_mode[SD_LBP_ZERO], 20))
 354                 sd_config_discard(sdkp, SD_LBP_ZERO);
 355         else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20))
 356                 sd_config_discard(sdkp, SD_LBP_DISABLE);
 357         else
 358                 return -EINVAL;
 359
 360         return count;
 361 }
 362
 363 static struct device_attribute sd_disk_attrs[] = {
 364         __ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
 365                sd_store_cache_type),
 366         __ATTR(FUA, S_IRUGO, sd_show_fua, NULL),
 367         __ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart,
 368                sd_store_allow_restart),
 369         __ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
 370                sd_store_manage_start_stop),
 371         __ATTR(protection_type, S_IRUGO, sd_show_protection_type, NULL),
 372         __ATTR(protection_mode, S_IRUGO, sd_show_protection_mode, NULL),
 373         __ATTR(app_tag_own, S_IRUGO, sd_show_app_tag_own, NULL),
 374         __ATTR(thin_provisioning, S_IRUGO, sd_show_thin_provisioning, NULL),
 375         __ATTR(provisioning_mode, S_IRUGO|S_IWUSR, sd_show_provisioning_mode,
 376                sd_store_provisioning_mode),
 377         __ATTR_NULL,
 378 };
 379
 380 static struct class sd_disk_class = {
 381         .name           = "scsi_disk",
 382         .owner          = THIS_MODULE,
 383         .dev_release    = scsi_disk_release,
 384         .dev_attrs      = sd_disk_attrs,
 385 };
 386
 387 static struct scsi_driver sd_template = {
 388         .owner                  = THIS_MODULE,
 389         .gendrv = {
 390                 .name           = "sd",
 391                 .probe          = sd_probe,
 392                 .remove         = sd_remove,
 393                 .suspend        = sd_suspend,
 394                 .resume         = sd_resume,
 395                 .shutdown       = sd_shutdown,
 396         },
 397         .rescan                 = sd_rescan,
 398         .done                   = sd_done,
 399 };
 400
 401 /*
 402  * Device no to disk mapping:
 403  *
 404  *       major         disc2     disc  p1
 405  *   |............|.............|....|....| <- dev_t
 406  *    31        20 19          8 7  4 3  0
 407  *
 408  * Inside a major, we have 16k disks, however mapped non-
 409  * contiguously. The first 16 disks are for major0, the next
 410  * ones with major1, ... Disk 256 is for major0 again, disk 272
 411  * for major1, ...
 412  * As we stay compatible with our numbering scheme, we can reuse
 413  * the well-know SCSI majors 8, 65--71, 136--143.
 414  */
 415 static int sd_major(int major_idx)
 416 {
 417         switch (major_idx) {
 418         case 0:
 419                 return SCSI_DISK0_MAJOR;
 420         case 1 ... 7:
 421                 return SCSI_DISK1_MAJOR + major_idx - 1;
 422         case 8 ... 15:
 423                 return SCSI_DISK8_MAJOR + major_idx - 8;
 424         default:
 425                 BUG();
 426                 return 0;       /* shut up gcc */
 427         }
 428 }
 429
 430 static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
 431 {
 432         struct scsi_disk *sdkp = NULL;
 433
 434         if (disk->private_data) {
 435                 sdkp = scsi_disk(disk);
 436                 if (scsi_device_get(sdkp->device) == 0)
 437                         get_device(&sdkp->dev);
 438                 else
 439                         sdkp = NULL;
 440         }
 441         return sdkp;
 442 }
 443
 444 static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
 445 {
 446         struct scsi_disk *sdkp;
 447
 448         mutex_lock(&sd_ref_mutex);
 449         sdkp = __scsi_disk_get(disk);
 450         mutex_unlock(&sd_ref_mutex);
 451         return sdkp;
 452 }
 453
 454 static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
 455 {
 456         struct scsi_disk *sdkp;
 457
 458         mutex_lock(&sd_ref_mutex);
 459         sdkp = dev_get_drvdata(dev);
 460         if (sdkp)
 461                 sdkp = __scsi_disk_get(sdkp->disk);
 462         mutex_unlock(&sd_ref_mutex);
 463         return sdkp;
 464 }
 465
 466 static void scsi_disk_put(struct scsi_disk *sdkp)
 467 {
 468         struct scsi_device *sdev = sdkp->device;
 469
 470         mutex_lock(&sd_ref_mutex);
 471         put_device(&sdkp->dev);
 472         scsi_device_put(sdev);
 473         mutex_unlock(&sd_ref_mutex);
 474 }
 475
 476 static void sd_prot_op(struct scsi_cmnd *scmd, unsigned int dif)
 477 {
 478         unsigned int prot_op = SCSI_PROT_NORMAL;
 479         unsigned int dix = scsi_prot_sg_count(scmd);
 480
 481         if (scmd->sc_data_direction == DMA_FROM_DEVICE) {
 482                 if (dif && dix)
 483                         prot_op = SCSI_PROT_READ_PASS;
 484                 else if (dif && !dix)
 485                         prot_op = SCSI_PROT_READ_STRIP;
 486                 else if (!dif && dix)
 487                         prot_op = SCSI_PROT_READ_INSERT;
 488         } else {
 489                 if (dif && dix)
 490                         prot_op = SCSI_PROT_WRITE_PASS;
 491                 else if (dif && !dix)
 492                         prot_op = SCSI_PROT_WRITE_INSERT;
 493                 else if (!dif && dix)
 494                         prot_op = SCSI_PROT_WRITE_STRIP;
 495         }
 496
 497         scsi_set_prot_op(scmd, prot_op);
 498         scsi_set_prot_type(scmd, dif);
 499 }
 500
 501 static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
 502 {
 503         struct request_queue *q = sdkp->disk->queue;
 504         unsigned int logical_block_size = sdkp->device->sector_size;
 505         unsigned int max_blocks = 0;
 506
 507         q->limits.discard_zeroes_data = sdkp->lbprz;
 508         q->limits.discard_alignment = sdkp->unmap_alignment *
 509                 logical_block_size;
 510         q->limits.discard_granularity =
 511                 max(sdkp->physical_block_size,
 512                     sdkp->unmap_granularity * logical_block_size);
 513
 514         switch (mode) {
 515
 516         case SD_LBP_DISABLE:
 517                 q->limits.max_discard_sectors = 0;
 518                 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
 519                 return;
 520
 521         case SD_LBP_UNMAP:
 522                 max_blocks = min_not_zero(sdkp->max_unmap_blocks, 0xffffffff);
 523                 break;
 524
 525         case SD_LBP_WS16:
 526                 max_blocks = min_not_zero(sdkp->max_ws_blocks, 0xffffffff);
 527                 break;
 528
 529         case SD_LBP_WS10:
 530                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
 531                 break;
 532
 533         case SD_LBP_ZERO:
 534                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
 535                 q->limits.discard_zeroes_data = 1;
 536                 break;
 537         }
 538
 539         q->limits.max_discard_sectors = max_blocks * (logical_block_size >> 9);
 540         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
 541
 542         sdkp->provisioning_mode = mode;
 543 }
 544
 545 /**
 546  * scsi_setup_discard_cmnd - unmap blocks on thinly provisioned device
 547  * @sdp: scsi device to operate one
 548  * @rq: Request to prepare
 549  *
 550  * Will issue either UNMAP or WRITE SAME(16) depending on preference
 551  * indicated by target device.
 552  **/
 553 static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
 554 {
 555         struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
 556         struct bio *bio = rq->bio;
 557         sector_t sector = bio->bi_sector;
 558         unsigned int nr_sectors = bio_sectors(bio);
 559         unsigned int len;
 560         int ret;
 561         char *buf;
 562         struct page *page;
 563
 564         if (sdkp->device->sector_size == 4096) {
 565                 sector >>= 3;
 566                 nr_sectors >>= 3;
 567         }
 568
 569         rq->timeout = SD_TIMEOUT;
 570
 571         memset(rq->cmd, 0, rq->cmd_len);
 572
 573         page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
 574         if (!page)
 575                 return BLKPREP_DEFER;
 576
 577         switch (sdkp->provisioning_mode) {
 578         case SD_LBP_UNMAP:
 579                 buf = page_address(page);
 580
 581                 rq->cmd_len = 10;
 582                 rq->cmd[0] = UNMAP;
 583                 rq->cmd[8] = 24;
 584
 585                 put_unaligned_be16(6 + 16, &buf[0]);
 586                 put_unaligned_be16(16, &buf[2]);
 587                 put_unaligned_be64(sector, &buf[8]);
 588                 put_unaligned_be32(nr_sectors, &buf[16]);
 589
 590                 len = 24;
 591                 break;
 592
 593         case SD_LBP_WS16:
 594                 rq->cmd_len = 16;
 595                 rq->cmd[0] = WRITE_SAME_16;
 596                 rq->cmd[1] = 0x8; /* UNMAP */
 597                 put_unaligned_be64(sector, &rq->cmd[2]);
 598                 put_unaligned_be32(nr_sectors, &rq->cmd[10]);
 599
 600                 len = sdkp->device->sector_size;
 601                 break;
 602
 603         case SD_LBP_WS10:
 604         case SD_LBP_ZERO:
 605                 rq->cmd_len = 10;
 606                 rq->cmd[0] = WRITE_SAME;
 607                 if (sdkp->provisioning_mode == SD_LBP_WS10)
 608                         rq->cmd[1] = 0x8; /* UNMAP */
 609                 put_unaligned_be32(sector, &rq->cmd[2]);
 610                 put_unaligned_be16(nr_sectors, &rq->cmd[7]);
 611
 612                 len = sdkp->device->sector_size;
 613                 break;
 614
 615         default:
 616                 ret = BLKPREP_KILL;
 617                 goto out;
 618         }
 619
 620         blk_add_request_payload(rq, page, len);
 621         ret = scsi_setup_blk_pc_cmnd(sdp, rq);
 622         rq->buffer = page_address(page);
 623
 624 out:
 625         if (ret != BLKPREP_OK) {
 626                 __free_page(page);
 627                 rq->buffer = NULL;
 628         }
 629         return ret;
 630 }
 631
 632 static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq)
 633 {
 634         rq->timeout = SD_FLUSH_TIMEOUT;
 635         rq->retries = SD_MAX_RETRIES;
 636         rq->cmd[0] = SYNCHRONIZE_CACHE;
 637         rq->cmd_len = 10;
 638
 639         return scsi_setup_blk_pc_cmnd(sdp, rq);
 640 }
 641
 642 static void sd_unprep_fn(struct request_queue *q, struct request *rq)
 643 {
 644         struct scsi_cmnd *SCpnt = rq->special;
 645
 646         if (rq->cmd_flags & REQ_DISCARD) {
 647                 free_page((unsigned long)rq->buffer);
 648                 rq->buffer = NULL;
 649         }
 650         if (SCpnt->cmnd != rq->cmd) {
 651                 mempool_free(SCpnt->cmnd, sd_cdb_pool);
 652                 SCpnt->cmnd = NULL;
 653                 SCpnt->cmd_len = 0;
 654         }
 655 }
 656
 657 /**
 658  *      sd_init_command - build a scsi (read or write) command from
 659  *      information in the request structure.
 660  *      @SCpnt: pointer to mid-level's per scsi command structure that
 661  *      contains request and into which the scsi command is written
 662  *
 663  *      Returns 1 if successful and 0 if error (or cannot be done now).
 664  **/
 665 static int sd_prep_fn(struct request_queue *q, struct request *rq)
 666 {
 667         struct scsi_cmnd *SCpnt;
 668         struct scsi_device *sdp = q->queuedata;
 669         struct gendisk *disk = rq->rq_disk;
 670         struct scsi_disk *sdkp;
 671         sector_t block = blk_rq_pos(rq);
 672         sector_t threshold;
 673         unsigned int this_count = blk_rq_sectors(rq);
 674         int ret, host_dif;
 675         unsigned char protect;
 676
 677         /*
 678          * Discard request come in as REQ_TYPE_FS but we turn them into
 679          * block PC requests to make life easier.
 680          */
 681         if (rq->cmd_flags & REQ_DISCARD) {
 682                 ret = scsi_setup_discard_cmnd(sdp, rq);
 683                 goto out;
 684         } else if (rq->cmd_flags & REQ_FLUSH) {
 685                 ret = scsi_setup_flush_cmnd(sdp, rq);
 686                 goto out;
 687         } else if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
 688                 ret = scsi_setup_blk_pc_cmnd(sdp, rq);
 689                 goto out;
 690         } else if (rq->cmd_type != REQ_TYPE_FS) {
 691                 ret = BLKPREP_KILL;
 692                 goto out;
 693         }
 694         ret = scsi_setup_fs_cmnd(sdp, rq);
 695         if (ret != BLKPREP_OK)
 696                 goto out;
 697         SCpnt = rq->special;
 698         sdkp = scsi_disk(disk);
 699
 700         /* from here on until we're complete, any goto out
 701          * is used for a killable error condition */
 702         ret = BLKPREP_KILL;
 703
 704         SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
 705                                         "sd_init_command: block=%llu, "
 706                                         "count=%d\n",
 707                                         (unsigned long long)block,
 708                                         this_count));
 709
 710         if (!sdp || !scsi_device_online(sdp) ||
 711             block + blk_rq_sectors(rq) > get_capacity(disk)) {
 712                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 713                                                 "Finishing %u sectors\n",
 714                                                 blk_rq_sectors(rq)));
 715                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 716                                                 "Retry with 0x%p\n", SCpnt));
 717                 goto out;
 718         }
 719
 720         if (sdp->changed) {
 721                 /*
 722                  * quietly refuse to do anything to a changed disc until
 723                  * the changed bit has been reset
 724                  */
 725                 /* printk("SCSI disk has been changed or is not present. Prohibiting further I/O.\n"); */
 726                 goto out;
 727         }
 728
 729         /*
 730          * Some SD card readers can't handle multi-sector accesses which touch
 731          * the last one or two hardware sectors.  Split accesses as needed.
 732          */
 733         threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
 734                 (sdp->sector_size / 512);
 735
 736         if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
 737                 if (block < threshold) {
 738                         /* Access up to the threshold but not beyond */
 739                         this_count = threshold - block;
 740                 } else {
 741                         /* Access only a single hardware sector */
 742                         this_count = sdp->sector_size / 512;
 743                 }
 744         }
 745
 746         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
 747                                         (unsigned long long)block));
 748
 749         /*
 750          * If we have a 1K hardware sectorsize, prevent access to single
 751          * 512 byte sectors.  In theory we could handle this - in fact
 752          * the scsi cdrom driver must be able to handle this because
 753          * we typically use 1K blocksizes, and cdroms typically have
 754          * 2K hardware sectorsizes.  Of course, things are simpler
 755          * with the cdrom, since it is read-only.  For performance
 756          * reasons, the filesystems should be able to handle this
 757          * and not force the scsi disk driver to use bounce buffers
 758          * for this.
 759          */
 760         if (sdp->sector_size == 1024) {
 761                 if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
 762                         scmd_printk(KERN_ERR, SCpnt,
 763                                     "Bad block number requested\n");
 764                         goto out;
 765                 } else {
 766                         block = block >> 1;
 767                         this_count = this_count >> 1;
 768                 }
 769         }
 770         if (sdp->sector_size == 2048) {
 771                 if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
 772                         scmd_printk(KERN_ERR, SCpnt,
 773                                     "Bad block number requested\n");
 774                         goto out;
 775                 } else {
 776                         block = block >> 2;
 777                         this_count = this_count >> 2;
 778                 }
 779         }
 780         if (sdp->sector_size == 4096) {
 781                 if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
 782                         scmd_printk(KERN_ERR, SCpnt,
 783                                     "Bad block number requested\n");
 784                         goto out;
 785                 } else {
 786                         block = block >> 3;
 787                         this_count = this_count >> 3;
 788                 }
 789         }
 790         if (rq_data_dir(rq) == WRITE) {
 791                 if (!sdp->writeable) {
 792                         goto out;
 793                 }
 794                 SCpnt->cmnd[0] = WRITE_6;
 795                 SCpnt->sc_data_direction = DMA_TO_DEVICE;
 796
 797                 if (blk_integrity_rq(rq) &&
 798                     sd_dif_prepare(rq, block, sdp->sector_size) == -EIO)
 799                         goto out;
 800
 801         } else if (rq_data_dir(rq) == READ) {
 802                 SCpnt->cmnd[0] = READ_6;
 803                 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
 804         } else {
 805                 scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
 806                 goto out;
 807         }
 808
 809         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 810                                         "%s %d/%u 512 byte blocks.\n",
 811                                         (rq_data_dir(rq) == WRITE) ?
 812                                         "writing" : "reading", this_count,
 813                                         blk_rq_sectors(rq)));
 814
 815         /* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
 816         host_dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
 817         if (host_dif)
 818                 protect = 1 << 5;
 819         else
 820                 protect = 0;
 821
 822         if (host_dif == SD_DIF_TYPE2_PROTECTION) {
 823                 SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
 824
 825                 if (unlikely(SCpnt->cmnd == NULL)) {
 826                         ret = BLKPREP_DEFER;
 827                         goto out;
 828                 }
 829
 830                 SCpnt->cmd_len = SD_EXT_CDB_SIZE;
 831                 memset(SCpnt->cmnd, 0, SCpnt->cmd_len);
 832                 SCpnt->cmnd[0] = VARIABLE_LENGTH_CMD;
 833                 SCpnt->cmnd[7] = 0x18;
 834                 SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
 835                 SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
 836
 837                 /* LBA */
 838                 SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
 839                 SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
 840                 SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
 841                 SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
 842                 SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
 843                 SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
 844                 SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
 845                 SCpnt->cmnd[19] = (unsigned char) block & 0xff;
 846
 847                 /* Expected Indirect LBA */
 848                 SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
 849                 SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
 850                 SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
 851                 SCpnt->cmnd[23] = (unsigned char) block & 0xff;
 852
 853                 /* Transfer length */
 854                 SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
 855                 SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
 856                 SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
 857                 SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
 858         } else if (block > 0xffffffff) {
 859                 SCpnt->cmnd[0] += READ_16 - READ_6;
 860                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
 861                 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
 862                 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
 863                 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
 864                 SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
 865                 SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
 866                 SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
 867                 SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
 868                 SCpnt->cmnd[9] = (unsigned char) block & 0xff;
 869                 SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
 870                 SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
 871                 SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
 872                 SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
 873                 SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
 874         } else if ((this_count > 0xff) || (block > 0x1fffff) ||
 875                    scsi_device_protection(SCpnt->device) ||
 876                    SCpnt->device->use_10_for_rw) {
 877                 if (this_count > 0xffff)
 878                         this_count = 0xffff;
 879
 880                 SCpnt->cmnd[0] += READ_10 - READ_6;
 881                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
 882                 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
 883                 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
 884                 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
 885                 SCpnt->cmnd[5] = (unsigned char) block & 0xff;
 886                 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
 887                 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
 888                 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
 889         } else {
 890                 if (unlikely(rq->cmd_flags & REQ_FUA)) {
 891                         /*
 892                          * This happens only if this drive failed
 893                          * 10byte rw command with ILLEGAL_REQUEST
 894                          * during operation and thus turned off
 895                          * use_10_for_rw.
 896                          */
 897                         scmd_printk(KERN_ERR, SCpnt,
 898                                     "FUA write on READ/WRITE(6) drive\n");
 899                         goto out;
 900                 }
 901
 902                 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
 903                 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
 904                 SCpnt->cmnd[3] = (unsigned char) block & 0xff;
 905                 SCpnt->cmnd[4] = (unsigned char) this_count;
 906                 SCpnt->cmnd[5] = 0;
 907         }
 908         SCpnt->sdb.length = this_count * sdp->sector_size;
 909
 910         /* If DIF or DIX is enabled, tell HBA how to handle request */
 911         if (host_dif || scsi_prot_sg_count(SCpnt))
 912                 sd_prot_op(SCpnt, host_dif);
 913
 914         /*
 915          * We shouldn't disconnect in the middle of a sector, so with a dumb
 916          * host adapter, it's safe to assume that we can at least transfer
 917          * this many bytes between each connect / disconnect.
 918          */
 919         SCpnt->transfersize = sdp->sector_size;
 920         SCpnt->underflow = this_count << 9;
 921         SCpnt->allowed = SD_MAX_RETRIES;
 922
 923         /*
 924          * This indicates that the command is ready from our end to be
 925          * queued.
 926          */
 927         ret = BLKPREP_OK;
 928  out:
 929         return scsi_prep_return(q, rq, ret);
 930 }
 931
 932 /**
 933  *      sd_open - open a scsi disk device
 934  *      @inode: only i_rdev member may be used
 935  *      @filp: only f_mode and f_flags may be used
 936  *
 937  *      Returns 0 if successful. Returns a negated errno value in case
 938  *      of error.
 939  *
 940  *      Note: This can be called from a user context (e.g. fsck(1) )
 941  *      or from within the kernel (e.g. as a result of a mount(1) ).
 942  *      In the latter case @inode and @filp carry an abridged amount
 943  *      of information as noted above.
 944  *
 945  *      Locking: called with bdev->bd_mutex held.
 946  **/
 947 static int sd_open(struct block_device *bdev, fmode_t mode)
 948 {
 949         struct scsi_disk *sdkp = scsi_disk_get(bdev->bd_disk);
 950         struct scsi_device *sdev;
 951         int retval;
 952
 953         if (!sdkp)
 954                 return -ENXIO;
 955
 956         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
 957
 958         sdev = sdkp->device;
 959
 960         retval = scsi_autopm_get_device(sdev);
 961         if (retval)
 962                 goto error_autopm;
 963
 964         /*
 965          * If the device is in error recovery, wait until it is done.
 966          * If the device is offline, then disallow any access to it.
 967          */
 968         retval = -ENXIO;
 969         if (!scsi_block_when_processing_errors(sdev))
 970                 goto error_out;
 971
 972         if (sdev->removable || sdkp->write_prot)
 973                 check_disk_change(bdev);
 974
 975         /*
 976          * If the drive is empty, just let the open fail.
 977          */
 978         retval = -ENOMEDIUM;
 979         if (sdev->removable && !sdkp->media_present && !(mode & FMODE_NDELAY))
 980                 goto error_out;
 981
 982         /*
 983          * If the device has the write protect tab set, have the open fail
 984          * if the user expects to be able to write to the thing.
 985          */
 986         retval = -EROFS;
 987         if (sdkp->write_prot && (mode & FMODE_WRITE))
 988                 goto error_out;
 989
 990         /*
 991          * It is possible that the disk changing stuff resulted in
 992          * the device being taken offline.  If this is the case,
 993          * report this to the user, and don't pretend that the
 994          * open actually succeeded.
 995          */
 996         retval = -ENXIO;
 997         if (!scsi_device_online(sdev))
 998                 goto error_out;
 999
1000         if ((atomic_inc_return(&sdkp->openers) == 1) && sdev->removable) {
1001                 if (scsi_block_when_processing_errors(sdev))
1002                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
1003         }
1004
1005         return 0;
1006
1007 error_out:
1008         scsi_autopm_put_device(sdev);
1009 error_autopm:
1010         scsi_disk_put(sdkp);
1011         return retval;
1012 }
1013
1014 /**
1015  *      sd_release - invoked when the (last) close(2) is called on this
1016  *      scsi disk.
1017  *      @inode: only i_rdev member may be used
1018  *      @filp: only f_mode and f_flags may be used
1019  *
1020  *      Returns 0.
1021  *
1022  *      Note: may block (uninterruptible) if error recovery is underway
1023  *      on this disk.
1024  *
1025  *      Locking: called with bdev->bd_mutex held.
1026  **/
1027 static int sd_release(struct gendisk *disk, fmode_t mode)
1028 {
1029         struct scsi_disk *sdkp = scsi_disk(disk);
1030         struct scsi_device *sdev = sdkp->device;
1031
1032         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
1033
1034         if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
1035                 if (scsi_block_when_processing_errors(sdev))
1036                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
1037         }
1038
1039         /*
1040          * XXX and what if there are packets in flight and this close()
1041          * XXX is followed by a "rmmod sd_mod"?
1042          */
1043
1044         scsi_autopm_put_device(sdev);
1045         scsi_disk_put(sdkp);
1046         return 0;
1047 }
1048
1049 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1050 {
1051         struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
1052         struct scsi_device *sdp = sdkp->device;
1053         struct Scsi_Host *host = sdp->host;
1054         int diskinfo[4];
1055
1056         /* default to most commonly used values */
1057         diskinfo[0] = 0x40;     /* 1 << 6 */
1058         diskinfo[1] = 0x20;     /* 1 << 5 */
1059         diskinfo[2] = sdkp->capacity >> 11;
1060
1061         /* override with calculated, extended default, or driver values */
1062         if (host->hostt->bios_param)
1063                 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
1064         else
1065                 scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
1066
1067         geo->heads = diskinfo[0];
1068         geo->sectors = diskinfo[1];
1069         geo->cylinders = diskinfo[2];
1070         return 0;
1071 }
1072
1073 /**
1074  *      sd_ioctl - process an ioctl
1075  *      @inode: only i_rdev/i_bdev members may be used
1076  *      @filp: only f_mode and f_flags may be used
1077  *      @cmd: ioctl command number
1078  *      @arg: this is third argument given to ioctl(2) system call.
1079  *      Often contains a pointer.
1080  *
1081  *      Returns 0 if successful (some ioctls return positive numbers on
1082  *      success as well). Returns a negated errno value in case of error.
1083  *
1084  *      Note: most ioctls are forward onto the block subsystem or further
1085  *      down in the scsi subsystem.
1086  **/
1087 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
1088                     unsigned int cmd, unsigned long arg)
1089 {
1090         struct gendisk *disk = bdev->bd_disk;
1091         struct scsi_disk *sdkp = scsi_disk(disk);
1092         struct scsi_device *sdp = sdkp->device;
1093         void __user *p = (void __user *)arg;
1094         int error;
1095
1096         SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
1097                                     "cmd=0x%x\n", disk->disk_name, cmd));
1098
1099         error = scsi_verify_blk_ioctl(bdev, cmd);
1100         if (error < 0)
1101                 return error;
1102
1103         /*
1104          * If we are in the middle of error recovery, don't let anyone
1105          * else try and use this device.  Also, if error recovery fails, it
1106          * may try and take the device offline, in which case all further
1107          * access to the device is prohibited.
1108          */
1109         error = scsi_nonblockable_ioctl(sdp, cmd, p,
1110                                         (mode & FMODE_NDELAY) != 0);
1111         if (!scsi_block_when_processing_errors(sdp) || !error)
1112                 goto out;
1113
1114         /*
1115          * Send SCSI addressing ioctls directly to mid level, send other
1116          * ioctls to block level and then onto mid level if they can't be
1117          * resolved.
1118          */
1119         switch (cmd) {
1120                 case SCSI_IOCTL_GET_IDLUN:
1121                 case SCSI_IOCTL_GET_BUS_NUMBER:
1122                         error = scsi_ioctl(sdp, cmd, p);
1123                         break;
1124                 default:
1125                         error = scsi_cmd_blk_ioctl(bdev, mode, cmd, p);
1126                         if (error != -ENOTTY)
1127                                 break;
1128                         error = scsi_ioctl(sdp, cmd, p);
1129                         break;
1130         }
1131 out:
1132         return error;
1133 }
1134
1135 static void set_media_not_present(struct scsi_disk *sdkp)
1136 {
1137         if (sdkp->media_present)
1138                 sdkp->device->changed = 1;
1139
1140         if (sdkp->device->removable) {
1141                 sdkp->media_present = 0;
1142                 sdkp->capacity = 0;
1143         }
1144 }
1145
1146 static int media_not_present(struct scsi_disk *sdkp,
1147                              struct scsi_sense_hdr *sshdr)
1148 {
1149         if (!scsi_sense_valid(sshdr))
1150                 return 0;
1151
1152         /* not invoked for commands that could return deferred errors */
1153         switch (sshdr->sense_key) {
1154         case UNIT_ATTENTION:
1155         case NOT_READY:
1156                 /* medium not present */
1157                 if (sshdr->asc == 0x3A) {
1158                         set_media_not_present(sdkp);
1159                         return 1;
1160                 }
1161         }
1162         return 0;
1163 }
1164
1165 /**
1166  *      sd_check_events - check media events
1167  *      @disk: kernel device descriptor
1168  *      @clearing: disk events currently being cleared
1169  *
1170  *      Returns mask of DISK_EVENT_*.
1171  *
1172  *      Note: this function is invoked from the block subsystem.
1173  **/
1174 static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
1175 {
1176         struct scsi_disk *sdkp = scsi_disk(disk);
1177         struct scsi_device *sdp = sdkp->device;
1178         struct scsi_sense_hdr *sshdr = NULL;
1179         int retval;
1180
1181         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
1182
1183         /*
1184          * If the device is offline, don't send any commands - just pretend as
1185          * if the command failed.  If the device ever comes back online, we
1186          * can deal with it then.  It is only because of unrecoverable errors
1187          * that we would ever take a device offline in the first place.
1188          */
1189         if (!scsi_device_online(sdp)) {
1190                 set_media_not_present(sdkp);
1191                 goto out;
1192         }
1193
1194         /*
1195          * Using TEST_UNIT_READY enables differentiation between drive with
1196          * no cartridge loaded - NOT READY, drive with changed cartridge -
1197          * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
1198          *
1199          * Drives that auto spin down. eg iomega jaz 1G, will be started
1200          * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
1201          * sd_revalidate() is called.
1202          */
1203         retval = -ENODEV;
1204
1205         if (scsi_block_when_processing_errors(sdp)) {
1206                 sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
1207                 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
1208                                               sshdr);
1209         }
1210
1211         /* failed to execute TUR, assume media not present */
1212         if (host_byte(retval)) {
1213                 set_media_not_present(sdkp);
1214                 goto out;
1215         }
1216
1217         if (media_not_present(sdkp, sshdr))
1218                 goto out;
1219
1220         /*
1221          * For removable scsi disk we have to recognise the presence
1222          * of a disk in the drive.
1223          */
1224         if (!sdkp->media_present)
1225                 sdp->changed = 1;
1226         sdkp->media_present = 1;
1227 out:
1228         /*
1229          * sdp->changed is set under the following conditions:
1230          *
1231          *      Medium present state has changed in either direction.
1232          *      Device has indicated UNIT_ATTENTION.
1233          */
1234         kfree(sshdr);
1235         retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
1236         sdp->changed = 0;
1237         return retval;
1238 }
1239
1240 static int sd_sync_cache(struct scsi_disk *sdkp)
1241 {
1242         int retries, res;
1243         struct scsi_device *sdp = sdkp->device;
1244         struct scsi_sense_hdr sshdr;
1245
1246         if (!scsi_device_online(sdp))
1247                 return -ENODEV;
1248
1249
1250         for (retries = 3; retries > 0; --retries) {
1251                 unsigned char cmd[10] = { 0 };
1252
1253                 cmd[0] = SYNCHRONIZE_CACHE;
1254                 /*
1255                  * Leave the rest of the command zero to indicate
1256                  * flush everything.
1257                  */
1258                 res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
1259                                        SD_FLUSH_TIMEOUT, SD_MAX_RETRIES, NULL);
1260                 if (res == 0)
1261                         break;
1262         }
1263
1264         if (res) {
1265                 sd_print_result(sdkp, res);
1266                 if (driver_byte(res) & DRIVER_SENSE)
1267                         sd_print_sense_hdr(sdkp, &sshdr);
1268         }
1269
1270         if (res)
1271                 return -EIO;
1272         return 0;
1273 }
1274
1275 static void sd_rescan(struct device *dev)
1276 {
1277         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
1278
1279         if (sdkp) {
1280                 revalidate_disk(sdkp->disk);
1281                 scsi_disk_put(sdkp);
1282         }
1283 }
1284
1285
1286 #ifdef CONFIG_COMPAT
1287 /*
1288  * This gets directly called from VFS. When the ioctl
1289  * is not recognized we go back to the other translation paths.
1290  */
1291 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
1292                            unsigned int cmd, unsigned long arg)
1293 {
1294         struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1295         int ret;
1296
1297         ret = scsi_verify_blk_ioctl(bdev, cmd);
1298         if (ret < 0)
1299                 return -ENOIOCTLCMD;
1300
1301         /*
1302          * If we are in the middle of error recovery, don't let anyone
1303          * else try and use this device.  Also, if error recovery fails, it
1304          * may try and take the device offline, in which case all further
1305          * access to the device is prohibited.
1306          */
1307         if (!scsi_block_when_processing_errors(sdev))
1308                 return -ENODEV;
1309
1310         if (sdev->host->hostt->compat_ioctl) {
1311                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
1312
1313                 return ret;
1314         }
1315
1316         /*
1317          * Let the static ioctl translation table take care of it.
1318          */
1319         return -ENOIOCTLCMD;
1320 }
1321 #endif
1322
1323 static const struct block_device_operations sd_fops = {
1324         .owner                  = THIS_MODULE,
1325         .open                   = sd_open,
1326         .release                = sd_release,
1327         .ioctl                  = sd_ioctl,
1328         .getgeo                 = sd_getgeo,
1329 #ifdef CONFIG_COMPAT
1330         .compat_ioctl           = sd_compat_ioctl,
1331 #endif
1332         .check_events           = sd_check_events,
1333         .revalidate_disk        = sd_revalidate_disk,
1334         .unlock_native_capacity = sd_unlock_native_capacity,
1335 };
1336
1337 static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
1338 {
1339         u64 start_lba = blk_rq_pos(scmd->request);
1340         u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
1341         u64 bad_lba;
1342         int info_valid;
1343         /*
1344          * resid is optional but mostly filled in.  When it's unused,
1345          * its value is zero, so we assume the whole buffer transferred
1346          */
1347         unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
1348         unsigned int good_bytes;
1349
1350         if (scmd->request->cmd_type != REQ_TYPE_FS)
1351                 return 0;
1352
1353         info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
1354                                              SCSI_SENSE_BUFFERSIZE,
1355                                              &bad_lba);
1356         if (!info_valid)
1357                 return 0;
1358
1359         if (scsi_bufflen(scmd) <= scmd->device->sector_size)
1360                 return 0;
1361
1362         if (scmd->device->sector_size < 512) {
1363                 /* only legitimate sector_size here is 256 */
1364                 start_lba <<= 1;
1365                 end_lba <<= 1;
1366         } else {
1367                 /* be careful ... don't want any overflows */
1368                 u64 factor = scmd->device->sector_size / 512;
1369                 do_div(start_lba, factor);
1370                 do_div(end_lba, factor);
1371         }
1372
1373         /* The bad lba was reported incorrectly, we have no idea where
1374          * the error is.
1375          */
1376         if (bad_lba < start_lba  || bad_lba >= end_lba)
1377                 return 0;
1378
1379         /* This computation should always be done in terms of
1380          * the resolution of the device's medium.
1381          */
1382         good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
1383         return min(good_bytes, transferred);
1384 }
1385
1386 /**
1387  *      sd_done - bottom half handler: called when the lower level
1388  *      driver has completed (successfully or otherwise) a scsi command.
1389  *      @SCpnt: mid-level's per command structure.
1390  *
1391  *      Note: potentially run from within an ISR. Must not block.
1392  **/
1393 static int sd_done(struct scsi_cmnd *SCpnt)
1394 {
1395         int result = SCpnt->result;
1396         unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
1397         struct scsi_sense_hdr sshdr;
1398         struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
1399         int sense_valid = 0;
1400         int sense_deferred = 0;
1401         unsigned char op = SCpnt->cmnd[0];
1402
1403         if ((SCpnt->request->cmd_flags & REQ_DISCARD) && !result)
1404                 scsi_set_resid(SCpnt, 0);
1405
1406         if (result) {
1407                 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
1408                 if (sense_valid)
1409                         sense_deferred = scsi_sense_is_deferred(&sshdr);
1410         }
1411 #ifdef CONFIG_SCSI_LOGGING
1412         SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
1413         if (sense_valid) {
1414                 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
1415                                                    "sd_done: sb[respc,sk,asc,"
1416                                                    "ascq]=%x,%x,%x,%x\n",
1417                                                    sshdr.response_code,
1418                                                    sshdr.sense_key, sshdr.asc,
1419                                                    sshdr.ascq));
1420         }
1421 #endif
1422         if (driver_byte(result) != DRIVER_SENSE &&
1423             (!sense_valid || sense_deferred))
1424                 goto out;
1425
1426         switch (sshdr.sense_key) {
1427         case HARDWARE_ERROR:
1428         case MEDIUM_ERROR:
1429                 good_bytes = sd_completed_bytes(SCpnt);
1430                 break;
1431         case RECOVERED_ERROR:
1432                 good_bytes = scsi_bufflen(SCpnt);
1433                 break;
1434         case NO_SENSE:
1435                 /* This indicates a false check condition, so ignore it.  An
1436                  * unknown amount of data was transferred so treat it as an
1437                  * error.
1438                  */
1439                 scsi_print_sense("sd", SCpnt);
1440                 SCpnt->result = 0;
1441                 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1442                 break;
1443         case ABORTED_COMMAND:
1444                 if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
1445                         good_bytes = sd_completed_bytes(SCpnt);
1446                 break;
1447         case ILLEGAL_REQUEST:
1448                 if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
1449                         good_bytes = sd_completed_bytes(SCpnt);
1450                 /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
1451                 if ((sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1452                     (op == UNMAP || op == WRITE_SAME_16 || op == WRITE_SAME))
1453                         sd_config_discard(sdkp, SD_LBP_DISABLE);
1454                 break;
1455         default:
1456                 break;
1457         }
1458  out:
1459         if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
1460                 sd_dif_complete(SCpnt, good_bytes);
1461
1462         return good_bytes;
1463 }
1464
1465 /*
1466  * spinup disk - called only in sd_revalidate_disk()
1467  */
1468 static void
1469 sd_spinup_disk(struct scsi_disk *sdkp)
1470 {
1471         unsigned char cmd[10];
1472         unsigned long spintime_expire = 0;
1473         int retries, spintime;
1474         unsigned int the_result;
1475         struct scsi_sense_hdr sshdr;
1476         int sense_valid = 0;
1477
1478         spintime = 0;
1479
1480         /* Spin up drives, as required.  Only do this at boot time */
1481         /* Spinup needs to be done for module loads too. */
1482         do {
1483                 retries = 0;
1484
1485                 do {
1486                         cmd[0] = TEST_UNIT_READY;
1487                         memset((void *) &cmd[1], 0, 9);
1488
1489                         the_result = scsi_execute_req(sdkp->device, cmd,
1490                                                       DMA_NONE, NULL, 0,
1491                                                       &sshdr, SD_TIMEOUT,
1492                                                       SD_MAX_RETRIES, NULL);
1493
1494                         /*
1495                          * If the drive has indicated to us that it
1496                          * doesn't have any media in it, don't bother
1497                          * with any more polling.
1498                          */
1499                         if (media_not_present(sdkp, &sshdr))
1500                                 return;
1501
1502                         if (the_result)
1503                                 sense_valid = scsi_sense_valid(&sshdr);
1504                         retries++;
1505                 } while (retries < 3 &&
1506                          (!scsi_status_is_good(the_result) ||
1507                           ((driver_byte(the_result) & DRIVER_SENSE) &&
1508                           sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1509
1510                 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1511                         /* no sense, TUR either succeeded or failed
1512                          * with a status error */
1513                         if(!spintime && !scsi_status_is_good(the_result)) {
1514                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1515                                 sd_print_result(sdkp, the_result);
1516                         }
1517                         break;
1518                 }
1519
1520                 /*
1521                  * The device does not want the automatic start to be issued.
1522                  */
1523                 if (sdkp->device->no_start_on_add)
1524                         break;
1525
1526                 if (sense_valid && sshdr.sense_key == NOT_READY) {
1527                         if (sshdr.asc == 4 && sshdr.ascq == 3)
1528                                 break;  /* manual intervention required */
1529                         if (sshdr.asc == 4 && sshdr.ascq == 0xb)
1530                                 break;  /* standby */
1531                         if (sshdr.asc == 4 && sshdr.ascq == 0xc)
1532                                 break;  /* unavailable */
1533                         /*
1534                          * Issue command to spin up drive when not ready
1535                          */
1536                         if (!spintime) {
1537                                 sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
1538                                 cmd[0] = START_STOP;
1539                                 cmd[1] = 1;     /* Return immediately */
1540                                 memset((void *) &cmd[2], 0, 8);
1541                                 cmd[4] = 1;     /* Start spin cycle */
1542                                 if (sdkp->device->start_stop_pwr_cond)
1543                                         cmd[4] |= 1 << 4;
1544                                 scsi_execute_req(sdkp->device, cmd, DMA_NONE,
1545                                                  NULL, 0, &sshdr,
1546                                                  SD_TIMEOUT, SD_MAX_RETRIES,
1547                                                  NULL);
1548                                 spintime_expire = jiffies + 100 * HZ;
1549                                 spintime = 1;
1550                         }
1551                         /* Wait 1 second for next try */
1552                         msleep(1000);
1553                         printk(".");
1554
1555                 /*
1556                  * Wait for USB flash devices with slow firmware.
1557                  * Yes, this sense key/ASC combination shouldn't
1558                  * occur here.  It's characteristic of these devices.
1559                  */
1560                 } else if (sense_valid &&
1561                                 sshdr.sense_key == UNIT_ATTENTION &&
1562                                 sshdr.asc == 0x28) {
1563                         if (!spintime) {
1564                                 spintime_expire = jiffies + 5 * HZ;
1565                                 spintime = 1;
1566                         }
1567                         /* Wait 1 second for next try */
1568                         msleep(1000);
1569                 } else {
1570                         /* we don't understand the sense code, so it's
1571                          * probably pointless to loop */
1572                         if(!spintime) {
1573                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1574                                 sd_print_sense_hdr(sdkp, &sshdr);
1575                         }
1576                         break;
1577                 }
1578
1579         } while (spintime && time_before_eq(jiffies, spintime_expire));
1580
1581         if (spintime) {
1582                 if (scsi_status_is_good(the_result))
1583                         printk("ready\n");
1584                 else
1585                         printk("not responding...\n");
1586         }
1587 }
1588
1589
1590 /*
1591  * Determine whether disk supports Data Integrity Field.
1592  */
1593 static void sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
1594 {
1595         struct scsi_device *sdp = sdkp->device;
1596         u8 type;
1597
1598         if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
1599                 return;
1600
1601         type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
1602
1603         if (type == sdkp->protection_type || !sdkp->first_scan)
1604                 return;
1605
1606         sdkp->protection_type = type;
1607
1608         if (type > SD_DIF_TYPE3_PROTECTION) {
1609                 sd_printk(KERN_ERR, sdkp, "formatted with unsupported " \
1610                           "protection type %u. Disabling disk!\n", type);
1611                 sdkp->capacity = 0;
1612                 return;
1613         }
1614
1615         if (scsi_host_dif_capable(sdp->host, type))
1616                 sd_printk(KERN_NOTICE, sdkp,
1617                           "Enabling DIF Type %u protection\n", type);
1618         else
1619                 sd_printk(KERN_NOTICE, sdkp,
1620                           "Disabling DIF Type %u protection\n", type);
1621 }
1622
1623 static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
1624                         struct scsi_sense_hdr *sshdr, int sense_valid,
1625                         int the_result)
1626 {
1627         sd_print_result(sdkp, the_result);
1628         if (driver_byte(the_result) & DRIVER_SENSE)
1629                 sd_print_sense_hdr(sdkp, sshdr);
1630         else
1631                 sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
1632
1633         /*
1634          * Set dirty bit for removable devices if not ready -
1635          * sometimes drives will not report this properly.
1636          */
1637         if (sdp->removable &&
1638             sense_valid && sshdr->sense_key == NOT_READY)
1639                 set_media_not_present(sdkp);
1640
1641         /*
1642          * We used to set media_present to 0 here to indicate no media
1643          * in the drive, but some drives fail read capacity even with
1644          * media present, so we can't do that.
1645          */
1646         sdkp->capacity = 0; /* unknown mapped to zero - as usual */
1647 }
1648
1649 #define RC16_LEN 32
1650 #if RC16_LEN > SD_BUF_SIZE
1651 #error RC16_LEN must not be more than SD_BUF_SIZE
1652 #endif
1653
1654 #define READ_CAPACITY_RETRIES_ON_RESET  10
1655
1656 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
1657                                                 unsigned char *buffer)
1658 {
1659         unsigned char cmd[16];
1660         struct scsi_sense_hdr sshdr;
1661         int sense_valid = 0;
1662         int the_result;
1663         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1664         unsigned int alignment;
1665         unsigned long long lba;
1666         unsigned sector_size;
1667
1668         if (sdp->no_read_capacity_16)
1669                 return -EINVAL;
1670
1671         do {
1672                 memset(cmd, 0, 16);
1673                 cmd[0] = SERVICE_ACTION_IN;
1674                 cmd[1] = SAI_READ_CAPACITY_16;
1675                 cmd[13] = RC16_LEN;
1676                 memset(buffer, 0, RC16_LEN);
1677
1678                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1679                                         buffer, RC16_LEN, &sshdr,
1680                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1681
1682                 if (media_not_present(sdkp, &sshdr))
1683                         return -ENODEV;
1684
1685                 if (the_result) {
1686                         sense_valid = scsi_sense_valid(&sshdr);
1687                         if (sense_valid &&
1688                             sshdr.sense_key == ILLEGAL_REQUEST &&
1689                             (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1690                             sshdr.ascq == 0x00)
1691                                 /* Invalid Command Operation Code or
1692                                  * Invalid Field in CDB, just retry
1693                                  * silently with RC10 */
1694                                 return -EINVAL;
1695                         if (sense_valid &&
1696                             sshdr.sense_key == UNIT_ATTENTION &&
1697                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1698                                 /* Device reset might occur several times,
1699                                  * give it one more chance */
1700                                 if (--reset_retries > 0)
1701                                         continue;
1702                 }
1703                 retries--;
1704
1705         } while (the_result && retries);
1706
1707         if (the_result) {
1708                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY(16) failed\n");
1709                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1710                 return -EINVAL;
1711         }
1712
1713         sector_size = get_unaligned_be32(&buffer[8]);
1714         lba = get_unaligned_be64(&buffer[0]);
1715
1716         sd_read_protection_type(sdkp, buffer);
1717
1718         if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
1719                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1720                         "kernel compiled with support for large block "
1721                         "devices.\n");
1722                 sdkp->capacity = 0;
1723                 return -EOVERFLOW;
1724         }
1725
1726         /* Logical blocks per physical block exponent */
1727         sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
1728
1729         /* Lowest aligned logical block */
1730         alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
1731         blk_queue_alignment_offset(sdp->request_queue, alignment);
1732         if (alignment && sdkp->first_scan)
1733                 sd_printk(KERN_NOTICE, sdkp,
1734                           "physical block alignment offset: %u\n", alignment);
1735
1736         if (buffer[14] & 0x80) { /* LBPME */
1737                 sdkp->lbpme = 1;
1738
1739                 if (buffer[14] & 0x40) /* LBPRZ */
1740                         sdkp->lbprz = 1;
1741
1742                 sd_config_discard(sdkp, SD_LBP_WS16);
1743         }
1744
1745         sdkp->capacity = lba + 1;
1746         return sector_size;
1747 }
1748
1749 static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
1750                                                 unsigned char *buffer)
1751 {
1752         unsigned char cmd[16];
1753         struct scsi_sense_hdr sshdr;
1754         int sense_valid = 0;
1755         int the_result;
1756         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1757         sector_t lba;
1758         unsigned sector_size;
1759
1760         do {
1761                 cmd[0] = READ_CAPACITY;
1762                 memset(&cmd[1], 0, 9);
1763                 memset(buffer, 0, 8);
1764
1765                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1766                                         buffer, 8, &sshdr,
1767                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1768
1769                 if (media_not_present(sdkp, &sshdr))
1770                         return -ENODEV;
1771
1772                 if (the_result) {
1773                         sense_valid = scsi_sense_valid(&sshdr);
1774                         if (sense_valid &&
1775                             sshdr.sense_key == UNIT_ATTENTION &&
1776                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1777                                 /* Device reset might occur several times,
1778                                  * give it one more chance */
1779                                 if (--reset_retries > 0)
1780                                         continue;
1781                 }
1782                 retries--;
1783
1784         } while (the_result && retries);
1785
1786         if (the_result) {
1787                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY failed\n");
1788                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1789                 return -EINVAL;
1790         }
1791
1792         sector_size = get_unaligned_be32(&buffer[4]);
1793         lba = get_unaligned_be32(&buffer[0]);
1794
1795         if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
1796                 /* Some buggy (usb cardreader) devices return an lba of
1797                    0xffffffff when the want to report a size of 0 (with
1798                    which they really mean no media is present) */
1799                 sdkp->capacity = 0;
1800                 sdkp->physical_block_size = sector_size;
1801                 return sector_size;
1802         }
1803
1804         if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
1805                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1806                         "kernel compiled with support for large block "
1807                         "devices.\n");
1808                 sdkp->capacity = 0;
1809                 return -EOVERFLOW;
1810         }
1811
1812         sdkp->capacity = lba + 1;
1813         sdkp->physical_block_size = sector_size;
1814         return sector_size;
1815 }
1816
1817 static int sd_try_rc16_first(struct scsi_device *sdp)
1818 {
1819         if (sdp->host->max_cmd_len < 16)
1820                 return 0;
1821         if (sdp->scsi_level > SCSI_SPC_2)
1822                 return 1;
1823         if (scsi_device_protection(sdp))
1824                 return 1;
1825         return 0;
1826 }
1827
1828 /*
1829  * read disk capacity
1830  */
1831 static void
1832 sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
1833 {
1834         int sector_size;
1835         struct scsi_device *sdp = sdkp->device;
1836         sector_t old_capacity = sdkp->capacity;
1837
1838         if (sd_try_rc16_first(sdp)) {
1839                 sector_size = read_capacity_16(sdkp, sdp, buffer);
1840                 if (sector_size == -EOVERFLOW)
1841                         goto got_data;
1842                 if (sector_size == -ENODEV)
1843                         return;
1844                 if (sector_size < 0)
1845                         sector_size = read_capacity_10(sdkp, sdp, buffer);
1846                 if (sector_size < 0)
1847                         return;
1848         } else {
1849                 sector_size = read_capacity_10(sdkp, sdp, buffer);
1850                 if (sector_size == -EOVERFLOW)
1851                         goto got_data;
1852                 if (sector_size < 0)
1853                         return;
1854                 if ((sizeof(sdkp->capacity) > 4) &&
1855                     (sdkp->capacity > 0xffffffffULL)) {
1856                         int old_sector_size = sector_size;
1857                         sd_printk(KERN_NOTICE, sdkp, "Very big device. "
1858                                         "Trying to use READ CAPACITY(16).\n");
1859                         sector_size = read_capacity_16(sdkp, sdp, buffer);
1860                         if (sector_size < 0) {
1861                                 sd_printk(KERN_NOTICE, sdkp,
1862                                         "Using 0xffffffff as device size\n");
1863                                 sdkp->capacity = 1 + (sector_t) 0xffffffff;
1864                                 sector_size = old_sector_size;
1865                                 goto got_data;
1866                         }
1867                 }
1868         }
1869
1870         /* Some devices are known to return the total number of blocks,
1871          * not the highest block number.  Some devices have versions
1872          * which do this and others which do not.  Some devices we might
1873          * suspect of doing this but we don't know for certain.
1874          *
1875          * If we know the reported capacity is wrong, decrement it.  If
1876          * we can only guess, then assume the number of blocks is even
1877          * (usually true but not always) and err on the side of lowering
1878          * the capacity.
1879          */
1880         if (sdp->fix_capacity ||
1881             (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
1882                 sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
1883                                 "from its reported value: %llu\n",
1884                                 (unsigned long long) sdkp->capacity);
1885                 --sdkp->capacity;
1886         }
1887
1888 got_data:
1889         if (sector_size == 0) {
1890                 sector_size = 512;
1891                 sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
1892                           "assuming 512.\n");
1893         }
1894
1895         if (sector_size != 512 &&
1896             sector_size != 1024 &&
1897             sector_size != 2048 &&
1898             sector_size != 4096 &&
1899             sector_size != 256) {
1900                 sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
1901                           sector_size);
1902                 /*
1903                  * The user might want to re-format the drive with
1904                  * a supported sectorsize.  Once this happens, it
1905                  * would be relatively trivial to set the thing up.
1906                  * For this reason, we leave the thing in the table.
1907                  */
1908                 sdkp->capacity = 0;
1909                 /*
1910                  * set a bogus sector size so the normal read/write
1911                  * logic in the block layer will eventually refuse any
1912                  * request on this device without tripping over power
1913                  * of two sector size assumptions
1914                  */
1915                 sector_size = 512;
1916         }
1917         blk_queue_logical_block_size(sdp->request_queue, sector_size);
1918
1919         {
1920                 char cap_str_2[10], cap_str_10[10];
1921                 u64 sz = (u64)sdkp->capacity << ilog2(sector_size);
1922
1923                 string_get_size(sz, STRING_UNITS_2, cap_str_2,
1924                                 sizeof(cap_str_2));
1925                 string_get_size(sz, STRING_UNITS_10, cap_str_10,
1926                                 sizeof(cap_str_10));
1927
1928                 if (sdkp->first_scan || old_capacity != sdkp->capacity) {
1929                         sd_printk(KERN_NOTICE, sdkp,
1930                                   "%llu %d-byte logical blocks: (%s/%s)\n",
1931                                   (unsigned long long)sdkp->capacity,
1932                                   sector_size, cap_str_10, cap_str_2);
1933
1934                         if (sdkp->physical_block_size != sector_size)
1935                                 sd_printk(KERN_NOTICE, sdkp,
1936                                           "%u-byte physical blocks\n",
1937                                           sdkp->physical_block_size);
1938                 }
1939         }
1940
1941         /* Rescale capacity to 512-byte units */
1942         if (sector_size == 4096)
1943                 sdkp->capacity <<= 3;
1944         else if (sector_size == 2048)
1945                 sdkp->capacity <<= 2;
1946         else if (sector_size == 1024)
1947                 sdkp->capacity <<= 1;
1948         else if (sector_size == 256)
1949                 sdkp->capacity >>= 1;
1950
1951         blk_queue_physical_block_size(sdp->request_queue,
1952                                       sdkp->physical_block_size);
1953         sdkp->device->sector_size = sector_size;
1954 }
1955
1956 /* called with buffer of length 512 */
1957 static inline int
1958 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
1959                  unsigned char *buffer, int len, struct scsi_mode_data *data,
1960                  struct scsi_sense_hdr *sshdr)
1961 {
1962         return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
1963                                SD_TIMEOUT, SD_MAX_RETRIES, data,
1964                                sshdr);
1965 }
1966
1967 /*
1968  * read write protect setting, if possible - called only in sd_revalidate_disk()
1969  * called with buffer of length SD_BUF_SIZE
1970  */
1971 static void
1972 sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
1973 {
1974         int res;
1975         struct scsi_device *sdp = sdkp->device;
1976         struct scsi_mode_data data;
1977         int old_wp = sdkp->write_prot;
1978
1979         set_disk_ro(sdkp->disk, 0);
1980         if (sdp->skip_ms_page_3f) {
1981                 sd_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
1982                 return;
1983         }
1984
1985         if (sdp->use_192_bytes_for_3f) {
1986                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
1987         } else {
1988                 /*
1989                  * First attempt: ask for all pages (0x3F), but only 4 bytes.
1990                  * We have to start carefully: some devices hang if we ask
1991                  * for more than is available.
1992                  */
1993                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
1994
1995                 /*
1996                  * Second attempt: ask for page 0 When only page 0 is
1997                  * implemented, a request for page 3F may return Sense Key
1998                  * 5: Illegal Request, Sense Code 24: Invalid field in
1999                  * CDB.
2000                  */
2001                 if (!scsi_status_is_good(res))
2002                         res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
2003
2004                 /*
2005                  * Third attempt: ask 255 bytes, as we did earlier.
2006                  */
2007                 if (!scsi_status_is_good(res))
2008                         res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
2009                                                &data, NULL);
2010         }
2011
2012         if (!scsi_status_is_good(res)) {
2013                 sd_printk(KERN_WARNING, sdkp,
2014                           "Test WP failed, assume Write Enabled\n");
2015         } else {
2016                 sdkp->write_prot = ((data.device_specific & 0x80) != 0);
2017                 set_disk_ro(sdkp->disk, sdkp->write_prot);
2018                 if (sdkp->first_scan || old_wp != sdkp->write_prot) {
2019                         sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
2020                                   sdkp->write_prot ? "on" : "off");
2021                         sd_printk(KERN_DEBUG, sdkp,
2022                                   "Mode Sense: %02x %02x %02x %02x\n",
2023                                   buffer[0], buffer[1], buffer[2], buffer[3]);
2024                 }
2025         }
2026 }
2027
2028 /*
2029  * sd_read_cache_type - called only from sd_revalidate_disk()
2030  * called with buffer of length SD_BUF_SIZE
2031  */
2032 static void
2033 sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
2034 {
2035         int len = 0, res;
2036         struct scsi_device *sdp = sdkp->device;
2037
2038         int dbd;
2039         int modepage;
2040         int first_len;
2041         struct scsi_mode_data data;
2042         struct scsi_sense_hdr sshdr;
2043         int old_wce = sdkp->WCE;
2044         int old_rcd = sdkp->RCD;
2045         int old_dpofua = sdkp->DPOFUA;
2046
2047
2048         if (sdkp->cache_override)
2049                 return;
2050
2051         first_len = 4;
2052         if (sdp->skip_ms_page_8) {
2053                 if (sdp->type == TYPE_RBC)
2054                         goto defaults;
2055                 else {
2056                         if (sdp->skip_ms_page_3f)
2057                                 goto defaults;
2058                         modepage = 0x3F;
2059                         if (sdp->use_192_bytes_for_3f)
2060                                 first_len = 192;
2061                         dbd = 0;
2062                 }
2063         } else if (sdp->type == TYPE_RBC) {
2064                 modepage = 6;
2065                 dbd = 8;
2066         } else {
2067                 modepage = 8;
2068                 dbd = 0;
2069         }
2070
2071         /* cautiously ask */
2072         res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
2073                         &data, &sshdr);
2074
2075         if (!scsi_status_is_good(res))
2076                 goto bad_sense;
2077
2078         if (!data.header_length) {
2079                 modepage = 6;
2080                 first_len = 0;
2081                 sd_printk(KERN_ERR, sdkp, "Missing header in MODE_SENSE response\n");
2082         }
2083
2084         /* that went OK, now ask for the proper length */
2085         len = data.length;
2086
2087         /*
2088          * We're only interested in the first three bytes, actually.
2089          * But the data cache page is defined for the first 20.
2090          */
2091         if (len < 3)
2092                 goto bad_sense;
2093         else if (len > SD_BUF_SIZE) {
2094                 sd_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
2095                           "data from %d to %d bytes\n", len, SD_BUF_SIZE);
2096                 len = SD_BUF_SIZE;
2097         }
2098         if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
2099                 len = 192;
2100
2101         /* Get the data */
2102         if (len > first_len)
2103                 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
2104                                 &data, &sshdr);
2105
2106         if (scsi_status_is_good(res)) {
2107                 int offset = data.header_length + data.block_descriptor_length;
2108
2109                 while (offset < len) {
2110                         u8 page_code = buffer[offset] & 0x3F;
2111                         u8 spf       = buffer[offset] & 0x40;
2112
2113                         if (page_code == 8 || page_code == 6) {
2114                                 /* We're interested only in the first 3 bytes.
2115                                  */
2116                                 if (len - offset <= 2) {
2117                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2118                                                   "mode parameter data\n");
2119                                         goto defaults;
2120                                 } else {
2121                                         modepage = page_code;
2122                                         goto Page_found;
2123                                 }
2124                         } else {
2125                                 /* Go to the next page */
2126                                 if (spf && len - offset > 3)
2127                                         offset += 4 + (buffer[offset+2] << 8) +
2128                                                 buffer[offset+3];
2129                                 else if (!spf && len - offset > 1)
2130                                         offset += 2 + buffer[offset+1];
2131                                 else {
2132                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2133                                                   "mode parameter data\n");
2134                                         goto defaults;
2135                                 }
2136                         }
2137                 }
2138
2139                 if (modepage == 0x3F) {
2140                         sd_printk(KERN_ERR, sdkp, "No Caching mode page "
2141                                   "present\n");
2142                         goto defaults;
2143                 } else if ((buffer[offset] & 0x3f) != modepage) {
2144                         sd_printk(KERN_ERR, sdkp, "Got wrong page\n");
2145                         goto defaults;
2146                 }
2147         Page_found:
2148                 if (modepage == 8) {
2149                         sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
2150                         sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
2151                 } else {
2152                         sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
2153                         sdkp->RCD = 0;
2154                 }
2155
2156                 sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
2157                 if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
2158                         sd_printk(KERN_NOTICE, sdkp,
2159                                   "Uses READ/WRITE(6), disabling FUA\n");
2160                         sdkp->DPOFUA = 0;
2161                 }
2162
2163                 if (sdkp->first_scan || old_wce != sdkp->WCE ||
2164                     old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
2165                         sd_printk(KERN_NOTICE, sdkp,
2166                                   "Write cache: %s, read cache: %s, %s\n",
2167                                   sdkp->WCE ? "enabled" : "disabled",
2168                                   sdkp->RCD ? "disabled" : "enabled",
2169                                   sdkp->DPOFUA ? "supports DPO and FUA"
2170                                   : "doesn't support DPO or FUA");
2171
2172                 return;
2173         }
2174
2175 bad_sense:
2176         if (scsi_sense_valid(&sshdr) &&
2177             sshdr.sense_key == ILLEGAL_REQUEST &&
2178             sshdr.asc == 0x24 && sshdr.ascq == 0x0)
2179                 /* Invalid field in CDB */
2180                 sd_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
2181         else
2182                 sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n");
2183
2184 defaults:
2185         sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n");
2186         sdkp->WCE = 0;
2187         sdkp->RCD = 0;
2188         sdkp->DPOFUA = 0;
2189 }
2190
2191 /*
2192  * The ATO bit indicates whether the DIF application tag is available
2193  * for use by the operating system.
2194  */
2195 static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
2196 {
2197         int res, offset;
2198         struct scsi_device *sdp = sdkp->device;
2199         struct scsi_mode_data data;
2200         struct scsi_sense_hdr sshdr;
2201
2202         if (sdp->type != TYPE_DISK)
2203                 return;
2204
2205         if (sdkp->protection_type == 0)
2206                 return;
2207
2208         res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
2209                               SD_MAX_RETRIES, &data, &sshdr);
2210
2211         if (!scsi_status_is_good(res) || !data.header_length ||
2212             data.length < 6) {
2213                 sd_printk(KERN_WARNING, sdkp,
2214                           "getting Control mode page failed, assume no ATO\n");
2215
2216                 if (scsi_sense_valid(&sshdr))
2217                         sd_print_sense_hdr(sdkp, &sshdr);
2218
2219                 return;
2220         }
2221
2222         offset = data.header_length + data.block_descriptor_length;
2223
2224         if ((buffer[offset] & 0x3f) != 0x0a) {
2225                 sd_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
2226                 return;
2227         }
2228
2229         if ((buffer[offset + 5] & 0x80) == 0)
2230                 return;
2231
2232         sdkp->ATO = 1;
2233
2234         return;
2235 }
2236
2237 /**
2238  * sd_read_block_limits - Query disk device for preferred I/O sizes.
2239  * @disk: disk to query
2240  */
2241 static void sd_read_block_limits(struct scsi_disk *sdkp)
2242 {
2243         unsigned int sector_sz = sdkp->device->sector_size;
2244         const int vpd_len = 64;
2245         unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
2246
2247         if (!buffer ||
2248             /* Block Limits VPD */
2249             scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
2250                 goto out;
2251
2252         blk_queue_io_min(sdkp->disk->queue,
2253                          get_unaligned_be16(&buffer[6]) * sector_sz);
2254         blk_queue_io_opt(sdkp->disk->queue,
2255                          get_unaligned_be32(&buffer[12]) * sector_sz);
2256
2257         if (buffer[3] == 0x3c) {
2258                 unsigned int lba_count, desc_count;
2259
2260                 sdkp->max_ws_blocks =
2261                         (u32) min_not_zero(get_unaligned_be64(&buffer[36]),
2262                                            (u64)0xffffffff);
2263
2264                 if (!sdkp->lbpme)
2265                         goto out;
2266
2267                 lba_count = get_unaligned_be32(&buffer[20]);
2268                 desc_count = get_unaligned_be32(&buffer[24]);
2269
2270                 if (lba_count && desc_count)
2271                         sdkp->max_unmap_blocks = lba_count;
2272
2273                 sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
2274
2275                 if (buffer[32] & 0x80)
2276                         sdkp->unmap_alignment =
2277                                 get_unaligned_be32(&buffer[32]) & ~(1 << 31);
2278
2279                 if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
2280
2281                         if (sdkp->max_unmap_blocks)
2282                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2283                         else
2284                                 sd_config_discard(sdkp, SD_LBP_WS16);
2285
2286                 } else {        /* LBP VPD page tells us what to use */
2287
2288                         if (sdkp->lbpu && sdkp->max_unmap_blocks)
2289                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2290                         else if (sdkp->lbpws)
2291                                 sd_config_discard(sdkp, SD_LBP_WS16);
2292                         else if (sdkp->lbpws10)
2293                                 sd_config_discard(sdkp, SD_LBP_WS10);
2294                         else
2295                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
2296                 }
2297         }
2298
2299  out:
2300         kfree(buffer);
2301 }
2302
2303 /**
2304  * sd_read_block_characteristics - Query block dev. characteristics
2305  * @disk: disk to query
2306  */
2307 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
2308 {
2309         unsigned char *buffer;
2310         u16 rot;
2311         const int vpd_len = 64;
2312
2313         buffer = kmalloc(vpd_len, GFP_KERNEL);
2314
2315         if (!buffer ||
2316             /* Block Device Characteristics VPD */
2317             scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
2318                 goto out;
2319
2320         rot = get_unaligned_be16(&buffer[4]);
2321
2322         if (rot == 1)
2323                 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
2324
2325  out:
2326         kfree(buffer);
2327 }
2328
2329 /**
2330  * sd_read_block_provisioning - Query provisioning VPD page
2331  * @disk: disk to query
2332  */
2333 static void sd_read_block_provisioning(struct scsi_disk *sdkp)
2334 {
2335         unsigned char *buffer;
2336         const int vpd_len = 8;
2337
2338         if (sdkp->lbpme == 0)
2339                 return;
2340
2341         buffer = kmalloc(vpd_len, GFP_KERNEL);
2342
2343         if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
2344                 goto out;
2345
2346         sdkp->lbpvpd    = 1;
2347         sdkp->lbpu      = (buffer[5] >> 7) & 1; /* UNMAP */
2348         sdkp->lbpws     = (buffer[5] >> 6) & 1; /* WRITE SAME(16) with UNMAP */
2349         sdkp->lbpws10   = (buffer[5] >> 5) & 1; /* WRITE SAME(10) with UNMAP */
2350
2351  out:
2352         kfree(buffer);
2353 }
2354
2355 static int sd_try_extended_inquiry(struct scsi_device *sdp)
2356 {
2357         /*
2358          * Although VPD inquiries can go to SCSI-2 type devices,
2359          * some USB ones crash on receiving them, and the pages
2360          * we currently ask for are for SPC-3 and beyond
2361          */
2362         if (sdp->scsi_level > SCSI_SPC_2)
2363                 return 1;
2364         return 0;
2365 }
2366
2367 /**
2368  *      sd_revalidate_disk - called the first time a new disk is seen,
2369  *      performs disk spin up, read_capacity, etc.
2370  *      @disk: struct gendisk we care about
2371  **/
2372 static int sd_revalidate_disk(struct gendisk *disk)
2373 {
2374         struct scsi_disk *sdkp = scsi_disk(disk);
2375         struct scsi_device *sdp = sdkp->device;
2376         unsigned char *buffer;
2377         unsigned flush = 0;
2378
2379         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
2380                                       "sd_revalidate_disk\n"));
2381
2382         /*
2383          * If the device is offline, don't try and read capacity or any
2384          * of the other niceties.
2385          */
2386         if (!scsi_device_online(sdp))
2387                 goto out;
2388
2389         buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
2390         if (!buffer) {
2391                 sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
2392                           "allocation failure.\n");
2393                 goto out;
2394         }
2395
2396         sd_spinup_disk(sdkp);
2397
2398         /*
2399          * Without media there is no reason to ask; moreover, some devices
2400          * react badly if we do.
2401          */
2402         if (sdkp->media_present) {
2403                 sd_read_capacity(sdkp, buffer);
2404
2405                 if (sd_try_extended_inquiry(sdp)) {
2406                         sd_read_block_provisioning(sdkp);
2407                         sd_read_block_limits(sdkp);
2408                         sd_read_block_characteristics(sdkp);
2409                 }
2410
2411                 sd_read_write_protect_flag(sdkp, buffer);
2412                 sd_read_cache_type(sdkp, buffer);
2413                 sd_read_app_tag_own(sdkp, buffer);
2414         }
2415
2416         sdkp->first_scan = 0;
2417
2418         /*
2419          * We now have all cache related info, determine how we deal
2420          * with flush requests.
2421          */
2422         if (sdkp->WCE) {
2423                 flush |= REQ_FLUSH;
2424                 if (sdkp->DPOFUA)
2425                         flush |= REQ_FUA;
2426         }
2427
2428         blk_queue_flush(sdkp->disk->queue, flush);
2429
2430         set_capacity(disk, sdkp->capacity);
2431         kfree(buffer);
2432
2433  out:
2434         return 0;
2435 }
2436
2437 /**
2438  *      sd_unlock_native_capacity - unlock native capacity
2439  *      @disk: struct gendisk to set capacity for
2440  *
2441  *      Block layer calls this function if it detects that partitions
2442  *      on @disk reach beyond the end of the device.  If the SCSI host
2443  *      implements ->unlock_native_capacity() method, it's invoked to
2444  *      give it a chance to adjust the device capacity.
2445  *
2446  *      CONTEXT:
2447  *      Defined by block layer.  Might sleep.
2448  */
2449 static void sd_unlock_native_capacity(struct gendisk *disk)
2450 {
2451         struct scsi_device *sdev = scsi_disk(disk)->device;
2452
2453         if (sdev->host->hostt->unlock_native_capacity)
2454                 sdev->host->hostt->unlock_native_capacity(sdev);
2455 }
2456
2457 /**
2458  *      sd_format_disk_name - format disk name
2459  *      @prefix: name prefix - ie. "sd" for SCSI disks
2460  *      @index: index of the disk to format name for
2461  *      @buf: output buffer
2462  *      @buflen: length of the output buffer
2463  *
2464  *      SCSI disk names starts at sda.  The 26th device is sdz and the
2465  *      27th is sdaa.  The last one for two lettered suffix is sdzz
2466  *      which is followed by sdaaa.
2467  *
2468  *      This is basically 26 base counting with one extra 'nil' entry
2469  *      at the beginning from the second digit on and can be
2470  *      determined using similar method as 26 base conversion with the
2471  *      index shifted -1 after each digit is computed.
2472  *
2473  *      CONTEXT:
2474  *      Don't care.
2475  *
2476  *      RETURNS:
2477  *      0 on success, -errno on failure.
2478  */
2479 static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
2480 {
2481         const int base = 'z' - 'a' + 1;
2482         char *begin = buf + strlen(prefix);
2483         char *end = buf + buflen;
2484         char *p;
2485         int unit;
2486
2487         p = end - 1;
2488         *p = '\0';
2489         unit = base;
2490         do {
2491                 if (p == begin)
2492                         return -EINVAL;
2493                 *--p = 'a' + (index % unit);
2494                 index = (index / unit) - 1;
2495         } while (index >= 0);
2496
2497         memmove(begin, p, end - p);
2498         memcpy(buf, prefix, strlen(prefix));
2499
2500         return 0;
2501 }
2502
2503 /*
2504  * The asynchronous part of sd_probe
2505  */
2506 static void sd_probe_async(void *data, async_cookie_t cookie)
2507 {
2508         struct scsi_disk *sdkp = data;
2509         struct scsi_device *sdp;
2510         struct gendisk *gd;
2511         u32 index;
2512         struct device *dev;
2513
2514         sdp = sdkp->device;
2515         gd = sdkp->disk;
2516         index = sdkp->index;
2517         dev = &sdp->sdev_gendev;
2518
2519         gd->major = sd_major((index & 0xf0) >> 4);
2520         gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
2521         gd->minors = SD_MINORS;
2522
2523         gd->fops = &sd_fops;
2524         gd->private_data = &sdkp->driver;
2525         gd->queue = sdkp->device->request_queue;
2526
2527         /* defaults, until the device tells us otherwise */
2528         sdp->sector_size = 512;
2529         sdkp->capacity = 0;
2530         sdkp->media_present = 1;
2531         sdkp->write_prot = 0;
2532         sdkp->cache_override = 0;
2533         sdkp->WCE = 0;
2534         sdkp->RCD = 0;
2535         sdkp->ATO = 0;
2536         sdkp->first_scan = 1;
2537
2538         sd_revalidate_disk(gd);
2539
2540         blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
2541         blk_queue_unprep_rq(sdp->request_queue, sd_unprep_fn);
2542
2543         gd->driverfs_dev = &sdp->sdev_gendev;
2544         gd->flags = GENHD_FL_EXT_DEVT;
2545         if (sdp->removable) {
2546                 gd->flags |= GENHD_FL_REMOVABLE;
2547                 gd->events |= DISK_EVENT_MEDIA_CHANGE;
2548         }
2549
2550         add_disk(gd);
2551         sd_dif_config_host(sdkp);
2552
2553         sd_revalidate_disk(gd);
2554
2555         sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
2556                   sdp->removable ? "removable " : "");
2557         scsi_autopm_put_device(sdp);
2558         put_device(&sdkp->dev);
2559 }
2560
2561 /**
2562  *      sd_probe - called during driver initialization and whenever a
2563  *      new scsi device is attached to the system. It is called once
2564  *      for each scsi device (not just disks) present.
2565  *      @dev: pointer to device object
2566  *
2567  *      Returns 0 if successful (or not interested in this scsi device
2568  *      (e.g. scanner)); 1 when there is an error.
2569  *
2570  *      Note: this function is invoked from the scsi mid-level.
2571  *      This function sets up the mapping between a given
2572  *      <host,channel,id,lun> (found in sdp) and new device name
2573  *      (e.g. /dev/sda). More precisely it is the block device major
2574  *      and minor number that is chosen here.
2575  *
2576  *      Assume sd_attach is not re-entrant (for time being)
2577  *      Also think about sd_attach() and sd_remove() running coincidentally.
2578  **/
2579 static int sd_probe(struct device *dev)
2580 {
2581         struct scsi_device *sdp = to_scsi_device(dev);
2582         struct scsi_disk *sdkp;
2583         struct gendisk *gd;
2584         int index;
2585         int error;
2586
2587         error = -ENODEV;
2588         if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
2589                 goto out;
2590
2591         SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
2592                                         "sd_attach\n"));
2593
2594         error = -ENOMEM;
2595         sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
2596         if (!sdkp)
2597                 goto out;
2598
2599         gd = alloc_disk(SD_MINORS);
2600         if (!gd)
2601                 goto out_free;
2602
2603         do {
2604                 if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
2605                         goto out_put;
2606
2607                 spin_lock(&sd_index_lock);
2608                 error = ida_get_new(&sd_index_ida, &index);
2609                 spin_unlock(&sd_index_lock);
2610         } while (error == -EAGAIN);
2611
2612         if (error) {
2613                 sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
2614                 goto out_put;
2615         }
2616
2617         error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
2618         if (error) {
2619                 sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name length exceeded.\n");
2620                 goto out_free_index;
2621         }
2622
2623         sdkp->device = sdp;
2624         sdkp->driver = &sd_template;
2625         sdkp->disk = gd;
2626         sdkp->index = index;
2627         atomic_set(&sdkp->openers, 0);
2628
2629         if (!sdp->request_queue->rq_timeout) {
2630                 if (sdp->type != TYPE_MOD)
2631                         blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
2632                 else
2633                         blk_queue_rq_timeout(sdp->request_queue,
2634                                              SD_MOD_TIMEOUT);
2635         }
2636
2637         device_initialize(&sdkp->dev);
2638         sdkp->dev.parent = dev;
2639         sdkp->dev.class = &sd_disk_class;
2640         dev_set_name(&sdkp->dev, dev_name(dev));
2641
2642         if (device_add(&sdkp->dev))
2643                 goto out_free_index;
2644
2645         get_device(dev);
2646         dev_set_drvdata(dev, sdkp);
2647
2648         get_device(&sdkp->dev); /* prevent release before async_schedule */
2649         async_schedule(sd_probe_async, sdkp);
2650
2651         return 0;
2652
2653  out_free_index:
2654         spin_lock(&sd_index_lock);
2655         ida_remove(&sd_index_ida, index);
2656         spin_unlock(&sd_index_lock);
2657  out_put:
2658         put_disk(gd);
2659  out_free:
2660         kfree(sdkp);
2661  out:
2662         return error;
2663 }
2664
2665 /**
2666  *      sd_remove - called whenever a scsi disk (previously recognized by
2667  *      sd_probe) is detached from the system. It is called (potentially
2668  *      multiple times) during sd module unload.
2669  *      @sdp: pointer to mid level scsi device object
2670  *
2671  *      Note: this function is invoked from the scsi mid-level.
2672  *      This function potentially frees up a device name (e.g. /dev/sdc)
2673  *      that could be re-used by a subsequent sd_probe().
2674  *      This function is not called when the built-in sd driver is "exit-ed".
2675  **/
2676 static int sd_remove(struct device *dev)
2677 {
2678         struct scsi_disk *sdkp;
2679
2680         sdkp = dev_get_drvdata(dev);
2681         scsi_autopm_get_device(sdkp->device);
2682
2683         async_synchronize_full();
2684         blk_queue_prep_rq(sdkp->device->request_queue, scsi_prep_fn);
2685         blk_queue_unprep_rq(sdkp->device->request_queue, NULL);
2686         device_del(&sdkp->dev);
2687         del_gendisk(sdkp->disk);
2688         sd_shutdown(dev);
2689
2690         mutex_lock(&sd_ref_mutex);
2691         dev_set_drvdata(dev, NULL);
2692         put_device(&sdkp->dev);
2693         mutex_unlock(&sd_ref_mutex);
2694
2695         return 0;
2696 }
2697
2698 /**
2699  *      scsi_disk_release - Called to free the scsi_disk structure
2700  *      @dev: pointer to embedded class device
2701  *
2702  *      sd_ref_mutex must be held entering this routine.  Because it is
2703  *      called on last put, you should always use the scsi_disk_get()
2704  *      scsi_disk_put() helpers which manipulate the semaphore directly
2705  *      and never do a direct put_device.
2706  **/
2707 static void scsi_disk_release(struct device *dev)
2708 {
2709         struct scsi_disk *sdkp = to_scsi_disk(dev);
2710         struct gendisk *disk = sdkp->disk;
2711
2712         spin_lock(&sd_index_lock);
2713         ida_remove(&sd_index_ida, sdkp->index);
2714         spin_unlock(&sd_index_lock);
2715
2716         disk->private_data = NULL;
2717         put_disk(disk);
2718         put_device(&sdkp->device->sdev_gendev);
2719
2720         kfree(sdkp);
2721 }
2722
2723 static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
2724 {
2725         unsigned char cmd[6] = { START_STOP };  /* START_VALID */
2726         struct scsi_sense_hdr sshdr;
2727         struct scsi_device *sdp = sdkp->device;
2728         int res;
2729
2730         if (start)
2731                 cmd[4] |= 1;    /* START */
2732
2733         if (sdp->start_stop_pwr_cond)
2734                 cmd[4] |= start ? 1 << 4 : 3 << 4;      /* Active or Standby */
2735
2736         if (!scsi_device_online(sdp))
2737                 return -ENODEV;
2738
2739         res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
2740                                SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2741         if (res) {
2742                 sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n");
2743                 sd_print_result(sdkp, res);
2744                 if (driver_byte(res) & DRIVER_SENSE)
2745                         sd_print_sense_hdr(sdkp, &sshdr);
2746         }
2747
2748         return res;
2749 }
2750
2751 /*
2752  * Send a SYNCHRONIZE CACHE instruction down to the device through
2753  * the normal SCSI command structure.  Wait for the command to
2754  * complete.
2755  */
2756 static void sd_shutdown(struct device *dev)
2757 {
2758         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2759
2760         if (!sdkp)
2761                 return;         /* this can happen */
2762
2763         if (sdkp->WCE) {
2764                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2765                 sd_sync_cache(sdkp);
2766         }
2767
2768         if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
2769                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2770                 sd_start_stop_device(sdkp, 0);
2771         }
2772
2773         scsi_disk_put(sdkp);
2774 }
2775
2776 static int sd_suspend(struct device *dev, pm_message_t mesg)
2777 {
2778         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2779         int ret = 0;
2780
2781         if (!sdkp)
2782                 return 0;       /* this can happen */
2783
2784         if (sdkp->WCE) {
2785                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2786                 ret = sd_sync_cache(sdkp);
2787                 if (ret)
2788                         goto done;
2789         }
2790
2791         if ((mesg.event & PM_EVENT_SLEEP) && sdkp->device->manage_start_stop) {
2792                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2793                 ret = sd_start_stop_device(sdkp, 0);
2794         }
2795
2796 done:
2797         scsi_disk_put(sdkp);
2798         return ret;
2799 }
2800
2801 static int sd_resume(struct device *dev)
2802 {
2803         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2804         int ret = 0;
2805
2806         if (!sdkp->device->manage_start_stop)
2807                 goto done;
2808
2809         sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
2810         ret = sd_start_stop_device(sdkp, 1);
2811
2812 done:
2813         scsi_disk_put(sdkp);
2814         return ret;
2815 }
2816
2817 /**
2818  *      init_sd - entry point for this driver (both when built in or when
2819  *      a module).
2820  *
2821  *      Note: this function registers this driver with the scsi mid-level.
2822  **/
2823 static int __init init_sd(void)
2824 {
2825         int majors = 0, i, err;
2826
2827         SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
2828
2829         for (i = 0; i < SD_MAJORS; i++)
2830                 if (register_blkdev(sd_major(i), "sd") == 0)
2831                         majors++;
2832
2833         if (!majors)
2834                 return -ENODEV;
2835
2836         err = class_register(&sd_disk_class);
2837         if (err)
2838                 goto err_out;
2839
2840         sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
2841                                          0, 0, NULL);
2842         if (!sd_cdb_cache) {
2843                 printk(KERN_ERR "sd: can't init extended cdb cache\n");
2844                 goto err_out_class;
2845         }
2846
2847         sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
2848         if (!sd_cdb_pool) {
2849                 printk(KERN_ERR "sd: can't init extended cdb pool\n");
2850                 goto err_out_cache;
2851         }
2852
2853         err = scsi_register_driver(&sd_template.gendrv);
2854         if (err)
2855                 goto err_out_driver;
2856
2857         return 0;
2858
2859 err_out_driver:
2860         mempool_destroy(sd_cdb_pool);
2861
2862 err_out_cache:
2863         kmem_cache_destroy(sd_cdb_cache);
2864
2865 err_out_class:
2866         class_unregister(&sd_disk_class);
2867 err_out:
2868         for (i = 0; i < SD_MAJORS; i++)
2869                 unregister_blkdev(sd_major(i), "sd");
2870         return err;
2871 }
2872
2873 /**
2874  *      exit_sd - exit point for this driver (when it is a module).
2875  *
2876  *      Note: this function unregisters this driver from the scsi mid-level.
2877  **/
2878 static void __exit exit_sd(void)
2879 {
2880         int i;
2881
2882         SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
2883
2884         scsi_unregister_driver(&sd_template.gendrv);
2885         mempool_destroy(sd_cdb_pool);
2886         kmem_cache_destroy(sd_cdb_cache);
2887
2888         class_unregister(&sd_disk_class);
2889
2890         for (i = 0; i < SD_MAJORS; i++)
2891                 unregister_blkdev(sd_major(i), "sd");
2892 }
2893
2894 module_init(init_sd);
2895 module_exit(exit_sd);
2896
2897 static void sd_print_sense_hdr(struct scsi_disk *sdkp,
2898                                struct scsi_sense_hdr *sshdr)
2899 {
2900         sd_printk(KERN_INFO, sdkp, " ");
2901         scsi_show_sense_hdr(sshdr);
2902         sd_printk(KERN_INFO, sdkp, " ");
2903         scsi_show_extd_sense(sshdr->asc, sshdr->ascq);
2904 }
2905
2906 static void sd_print_result(struct scsi_disk *sdkp, int result)
2907 {
2908         sd_printk(KERN_INFO, sdkp, " ");
2909         scsi_show_result(result);
2910 }
2911