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 <linux/pm_runtime.h>
  54 #include <asm/uaccess.h>
  55 #include <asm/unaligned.h>
  56
  57 #include <scsi/scsi.h>
  58 #include <scsi/scsi_cmnd.h>
  59 #include <scsi/scsi_dbg.h>
  60 #include <scsi/scsi_device.h>
  61 #include <scsi/scsi_driver.h>
  62 #include <scsi/scsi_eh.h>
  63 #include <scsi/scsi_host.h>
  64 #include <scsi/scsi_ioctl.h>
  65 #include <scsi/scsicam.h>
  66
  67 #include "sd.h"
  68 #include "scsi_priv.h"
  69 #include "scsi_logging.h"
  70
  71 MODULE_AUTHOR("Eric Youngdale");
  72 MODULE_DESCRIPTION("SCSI disk (sd) driver");
  73 MODULE_LICENSE("GPL");
  74
  75 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
  76 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
  77 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
  78 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
  79 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
  80 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
  81 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
  82 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
  83 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
  84 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
  85 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
  86 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
  87 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
  88 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
  89 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
  90 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
  91 MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
  92 MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
  93 MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
  94
  95 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
  96 #define SD_MINORS       16
  97 #else
  98 #define SD_MINORS       0
  99 #endif
 100
 101 static void sd_config_discard(struct scsi_disk *, unsigned int);
 102 static void sd_config_write_same(struct scsi_disk *);
 103 static int  sd_revalidate_disk(struct gendisk *);
 104 static void sd_unlock_native_capacity(struct gendisk *disk);
 105 static int  sd_probe(struct device *);
 106 static int  sd_remove(struct device *);
 107 static void sd_shutdown(struct device *);
 108 static int sd_suspend_system(struct device *);
 109 static int sd_suspend_runtime(struct device *);
 110 static int sd_resume(struct device *);
 111 static void sd_rescan(struct device *);
 112 static int sd_init_command(struct scsi_cmnd *SCpnt);
 113 static void sd_uninit_command(struct scsi_cmnd *SCpnt);
 114 static int sd_done(struct scsi_cmnd *);
 115 static int sd_eh_action(struct scsi_cmnd *, int);
 116 static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
 117 static void scsi_disk_release(struct device *cdev);
 118 static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
 119 static void sd_print_result(const struct scsi_disk *, const char *, int);
 120
 121 static DEFINE_SPINLOCK(sd_index_lock);
 122 static DEFINE_IDA(sd_index_ida);
 123
 124 /* This semaphore is used to mediate the 0->1 reference get in the
 125  * face of object destruction (i.e. we can't allow a get on an
 126  * object after last put) */
 127 static DEFINE_MUTEX(sd_ref_mutex);
 128
 129 static struct kmem_cache *sd_cdb_cache;
 130 static mempool_t *sd_cdb_pool;
 131
 132 static const char *sd_cache_types[] = {
 133         "write through", "none", "write back",
 134         "write back, no read (daft)"
 135 };
 136
 137 static void sd_set_flush_flag(struct scsi_disk *sdkp)
 138 {
 139         unsigned flush = 0;
 140
 141         if (sdkp->WCE) {
 142                 flush |= REQ_FLUSH;
 143                 if (sdkp->DPOFUA)
 144                         flush |= REQ_FUA;
 145         }
 146
 147         blk_queue_flush(sdkp->disk->queue, flush);
 148 }
 149
 150 static ssize_t
 151 cache_type_store(struct device *dev, struct device_attribute *attr,
 152                  const char *buf, size_t count)
 153 {
 154         int i, ct = -1, rcd, wce, sp;
 155         struct scsi_disk *sdkp = to_scsi_disk(dev);
 156         struct scsi_device *sdp = sdkp->device;
 157         char buffer[64];
 158         char *buffer_data;
 159         struct scsi_mode_data data;
 160         struct scsi_sense_hdr sshdr;
 161         static const char temp[] = "temporary ";
 162         int len;
 163
 164         if (sdp->type != TYPE_DISK)
 165                 /* no cache control on RBC devices; theoretically they
 166                  * can do it, but there's probably so many exceptions
 167                  * it's not worth the risk */
 168                 return -EINVAL;
 169
 170         if (strncmp(buf, temp, sizeof(temp) - 1) == 0) {
 171                 buf += sizeof(temp) - 1;
 172                 sdkp->cache_override = 1;
 173         } else {
 174                 sdkp->cache_override = 0;
 175         }
 176
 177         for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
 178                 len = strlen(sd_cache_types[i]);
 179                 if (strncmp(sd_cache_types[i], buf, len) == 0 &&
 180                     buf[len] == '\n') {
 181                         ct = i;
 182                         break;
 183                 }
 184         }
 185         if (ct < 0)
 186                 return -EINVAL;
 187         rcd = ct & 0x01 ? 1 : 0;
 188         wce = (ct & 0x02) && !sdkp->write_prot ? 1 : 0;
 189
 190         if (sdkp->cache_override) {
 191                 sdkp->WCE = wce;
 192                 sdkp->RCD = rcd;
 193                 sd_set_flush_flag(sdkp);
 194                 return count;
 195         }
 196
 197         if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
 198                             SD_MAX_RETRIES, &data, NULL))
 199                 return -EINVAL;
 200         len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
 201                   data.block_descriptor_length);
 202         buffer_data = buffer + data.header_length +
 203                 data.block_descriptor_length;
 204         buffer_data[2] &= ~0x05;
 205         buffer_data[2] |= wce << 2 | rcd;
 206         sp = buffer_data[0] & 0x80 ? 1 : 0;
 207         buffer_data[0] &= ~0x80;
 208
 209         if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
 210                              SD_MAX_RETRIES, &data, &sshdr)) {
 211                 if (scsi_sense_valid(&sshdr))
 212                         sd_print_sense_hdr(sdkp, &sshdr);
 213                 return -EINVAL;
 214         }
 215         revalidate_disk(sdkp->disk);
 216         return count;
 217 }
 218
 219 static ssize_t
 220 manage_start_stop_show(struct device *dev, struct device_attribute *attr,
 221                        char *buf)
 222 {
 223         struct scsi_disk *sdkp = to_scsi_disk(dev);
 224         struct scsi_device *sdp = sdkp->device;
 225
 226         return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
 227 }
 228
 229 static ssize_t
 230 manage_start_stop_store(struct device *dev, struct device_attribute *attr,
 231                         const char *buf, size_t count)
 232 {
 233         struct scsi_disk *sdkp = to_scsi_disk(dev);
 234         struct scsi_device *sdp = sdkp->device;
 235
 236         if (!capable(CAP_SYS_ADMIN))
 237                 return -EACCES;
 238
 239         sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
 240
 241         return count;
 242 }
 243 static DEVICE_ATTR_RW(manage_start_stop);
 244
 245 static ssize_t
 246 allow_restart_show(struct device *dev, struct device_attribute *attr, char *buf)
 247 {
 248         struct scsi_disk *sdkp = to_scsi_disk(dev);
 249
 250         return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
 251 }
 252
 253 static ssize_t
 254 allow_restart_store(struct device *dev, struct device_attribute *attr,
 255                     const char *buf, size_t count)
 256 {
 257         struct scsi_disk *sdkp = to_scsi_disk(dev);
 258         struct scsi_device *sdp = sdkp->device;
 259
 260         if (!capable(CAP_SYS_ADMIN))
 261                 return -EACCES;
 262
 263         if (sdp->type != TYPE_DISK)
 264                 return -EINVAL;
 265
 266         sdp->allow_restart = simple_strtoul(buf, NULL, 10);
 267
 268         return count;
 269 }
 270 static DEVICE_ATTR_RW(allow_restart);
 271
 272 static ssize_t
 273 cache_type_show(struct device *dev, struct device_attribute *attr, char *buf)
 274 {
 275         struct scsi_disk *sdkp = to_scsi_disk(dev);
 276         int ct = sdkp->RCD + 2*sdkp->WCE;
 277
 278         return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
 279 }
 280 static DEVICE_ATTR_RW(cache_type);
 281
 282 static ssize_t
 283 FUA_show(struct device *dev, struct device_attribute *attr, char *buf)
 284 {
 285         struct scsi_disk *sdkp = to_scsi_disk(dev);
 286
 287         return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
 288 }
 289 static DEVICE_ATTR_RO(FUA);
 290
 291 static ssize_t
 292 protection_type_show(struct device *dev, struct device_attribute *attr,
 293                      char *buf)
 294 {
 295         struct scsi_disk *sdkp = to_scsi_disk(dev);
 296
 297         return snprintf(buf, 20, "%u\n", sdkp->protection_type);
 298 }
 299
 300 static ssize_t
 301 protection_type_store(struct device *dev, struct device_attribute *attr,
 302                       const char *buf, size_t count)
 303 {
 304         struct scsi_disk *sdkp = to_scsi_disk(dev);
 305         unsigned int val;
 306         int err;
 307
 308         if (!capable(CAP_SYS_ADMIN))
 309                 return -EACCES;
 310
 311         err = kstrtouint(buf, 10, &val);
 312
 313         if (err)
 314                 return err;
 315
 316         if (val >= 0 && val <= SD_DIF_TYPE3_PROTECTION)
 317                 sdkp->protection_type = val;
 318
 319         return count;
 320 }
 321 static DEVICE_ATTR_RW(protection_type);
 322
 323 static ssize_t
 324 protection_mode_show(struct device *dev, struct device_attribute *attr,
 325                      char *buf)
 326 {
 327         struct scsi_disk *sdkp = to_scsi_disk(dev);
 328         struct scsi_device *sdp = sdkp->device;
 329         unsigned int dif, dix;
 330
 331         dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
 332         dix = scsi_host_dix_capable(sdp->host, sdkp->protection_type);
 333
 334         if (!dix && scsi_host_dix_capable(sdp->host, SD_DIF_TYPE0_PROTECTION)) {
 335                 dif = 0;
 336                 dix = 1;
 337         }
 338
 339         if (!dif && !dix)
 340                 return snprintf(buf, 20, "none\n");
 341
 342         return snprintf(buf, 20, "%s%u\n", dix ? "dix" : "dif", dif);
 343 }
 344 static DEVICE_ATTR_RO(protection_mode);
 345
 346 static ssize_t
 347 app_tag_own_show(struct device *dev, struct device_attribute *attr, char *buf)
 348 {
 349         struct scsi_disk *sdkp = to_scsi_disk(dev);
 350
 351         return snprintf(buf, 20, "%u\n", sdkp->ATO);
 352 }
 353 static DEVICE_ATTR_RO(app_tag_own);
 354
 355 static ssize_t
 356 thin_provisioning_show(struct device *dev, struct device_attribute *attr,
 357                        char *buf)
 358 {
 359         struct scsi_disk *sdkp = to_scsi_disk(dev);
 360
 361         return snprintf(buf, 20, "%u\n", sdkp->lbpme);
 362 }
 363 static DEVICE_ATTR_RO(thin_provisioning);
 364
 365 static const char *lbp_mode[] = {
 366         [SD_LBP_FULL]           = "full",
 367         [SD_LBP_UNMAP]          = "unmap",
 368         [SD_LBP_WS16]           = "writesame_16",
 369         [SD_LBP_WS10]           = "writesame_10",
 370         [SD_LBP_ZERO]           = "writesame_zero",
 371         [SD_LBP_DISABLE]        = "disabled",
 372 };
 373
 374 static ssize_t
 375 provisioning_mode_show(struct device *dev, struct device_attribute *attr,
 376                        char *buf)
 377 {
 378         struct scsi_disk *sdkp = to_scsi_disk(dev);
 379
 380         return snprintf(buf, 20, "%s\n", lbp_mode[sdkp->provisioning_mode]);
 381 }
 382
 383 static ssize_t
 384 provisioning_mode_store(struct device *dev, struct device_attribute *attr,
 385                         const char *buf, size_t count)
 386 {
 387         struct scsi_disk *sdkp = to_scsi_disk(dev);
 388         struct scsi_device *sdp = sdkp->device;
 389
 390         if (!capable(CAP_SYS_ADMIN))
 391                 return -EACCES;
 392
 393         if (sdp->type != TYPE_DISK)
 394                 return -EINVAL;
 395
 396         if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
 397                 sd_config_discard(sdkp, SD_LBP_UNMAP);
 398         else if (!strncmp(buf, lbp_mode[SD_LBP_WS16], 20))
 399                 sd_config_discard(sdkp, SD_LBP_WS16);
 400         else if (!strncmp(buf, lbp_mode[SD_LBP_WS10], 20))
 401                 sd_config_discard(sdkp, SD_LBP_WS10);
 402         else if (!strncmp(buf, lbp_mode[SD_LBP_ZERO], 20))
 403                 sd_config_discard(sdkp, SD_LBP_ZERO);
 404         else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20))
 405                 sd_config_discard(sdkp, SD_LBP_DISABLE);
 406         else
 407                 return -EINVAL;
 408
 409         return count;
 410 }
 411 static DEVICE_ATTR_RW(provisioning_mode);
 412
 413 static ssize_t
 414 max_medium_access_timeouts_show(struct device *dev,
 415                                 struct device_attribute *attr, char *buf)
 416 {
 417         struct scsi_disk *sdkp = to_scsi_disk(dev);
 418
 419         return snprintf(buf, 20, "%u\n", sdkp->max_medium_access_timeouts);
 420 }
 421
 422 static ssize_t
 423 max_medium_access_timeouts_store(struct device *dev,
 424                                  struct device_attribute *attr, const char *buf,
 425                                  size_t count)
 426 {
 427         struct scsi_disk *sdkp = to_scsi_disk(dev);
 428         int err;
 429
 430         if (!capable(CAP_SYS_ADMIN))
 431                 return -EACCES;
 432
 433         err = kstrtouint(buf, 10, &sdkp->max_medium_access_timeouts);
 434
 435         return err ? err : count;
 436 }
 437 static DEVICE_ATTR_RW(max_medium_access_timeouts);
 438
 439 static ssize_t
 440 max_write_same_blocks_show(struct device *dev, struct device_attribute *attr,
 441                            char *buf)
 442 {
 443         struct scsi_disk *sdkp = to_scsi_disk(dev);
 444
 445         return snprintf(buf, 20, "%u\n", sdkp->max_ws_blocks);
 446 }
 447
 448 static ssize_t
 449 max_write_same_blocks_store(struct device *dev, struct device_attribute *attr,
 450                             const char *buf, size_t count)
 451 {
 452         struct scsi_disk *sdkp = to_scsi_disk(dev);
 453         struct scsi_device *sdp = sdkp->device;
 454         unsigned long max;
 455         int err;
 456
 457         if (!capable(CAP_SYS_ADMIN))
 458                 return -EACCES;
 459
 460         if (sdp->type != TYPE_DISK)
 461                 return -EINVAL;
 462
 463         err = kstrtoul(buf, 10, &max);
 464
 465         if (err)
 466                 return err;
 467
 468         if (max == 0)
 469                 sdp->no_write_same = 1;
 470         else if (max <= SD_MAX_WS16_BLOCKS) {
 471                 sdp->no_write_same = 0;
 472                 sdkp->max_ws_blocks = max;
 473         }
 474
 475         sd_config_write_same(sdkp);
 476
 477         return count;
 478 }
 479 static DEVICE_ATTR_RW(max_write_same_blocks);
 480
 481 static struct attribute *sd_disk_attrs[] = {
 482         &dev_attr_cache_type.attr,
 483         &dev_attr_FUA.attr,
 484         &dev_attr_allow_restart.attr,
 485         &dev_attr_manage_start_stop.attr,
 486         &dev_attr_protection_type.attr,
 487         &dev_attr_protection_mode.attr,
 488         &dev_attr_app_tag_own.attr,
 489         &dev_attr_thin_provisioning.attr,
 490         &dev_attr_provisioning_mode.attr,
 491         &dev_attr_max_write_same_blocks.attr,
 492         &dev_attr_max_medium_access_timeouts.attr,
 493         NULL,
 494 };
 495 ATTRIBUTE_GROUPS(sd_disk);
 496
 497 static struct class sd_disk_class = {
 498         .name           = "scsi_disk",
 499         .owner          = THIS_MODULE,
 500         .dev_release    = scsi_disk_release,
 501         .dev_groups     = sd_disk_groups,
 502 };
 503
 504 static const struct dev_pm_ops sd_pm_ops = {
 505         .suspend                = sd_suspend_system,
 506         .resume                 = sd_resume,
 507         .poweroff               = sd_suspend_system,
 508         .restore                = sd_resume,
 509         .runtime_suspend        = sd_suspend_runtime,
 510         .runtime_resume         = sd_resume,
 511 };
 512
 513 static struct scsi_driver sd_template = {
 514         .gendrv = {
 515                 .name           = "sd",
 516                 .owner          = THIS_MODULE,
 517                 .probe          = sd_probe,
 518                 .remove         = sd_remove,
 519                 .shutdown       = sd_shutdown,
 520                 .pm             = &sd_pm_ops,
 521         },
 522         .rescan                 = sd_rescan,
 523         .init_command           = sd_init_command,
 524         .uninit_command         = sd_uninit_command,
 525         .done                   = sd_done,
 526         .eh_action              = sd_eh_action,
 527 };
 528
 529 /*
 530  * Dummy kobj_map->probe function.
 531  * The default ->probe function will call modprobe, which is
 532  * pointless as this module is already loaded.
 533  */
 534 static struct kobject *sd_default_probe(dev_t devt, int *partno, void *data)
 535 {
 536         return NULL;
 537 }
 538
 539 /*
 540  * Device no to disk mapping:
 541  *
 542  *       major         disc2     disc  p1
 543  *   |............|.............|....|....| <- dev_t
 544  *    31        20 19          8 7  4 3  0
 545  *
 546  * Inside a major, we have 16k disks, however mapped non-
 547  * contiguously. The first 16 disks are for major0, the next
 548  * ones with major1, ... Disk 256 is for major0 again, disk 272
 549  * for major1, ...
 550  * As we stay compatible with our numbering scheme, we can reuse
 551  * the well-know SCSI majors 8, 65--71, 136--143.
 552  */
 553 static int sd_major(int major_idx)
 554 {
 555         switch (major_idx) {
 556         case 0:
 557                 return SCSI_DISK0_MAJOR;
 558         case 1 ... 7:
 559                 return SCSI_DISK1_MAJOR + major_idx - 1;
 560         case 8 ... 15:
 561                 return SCSI_DISK8_MAJOR + major_idx - 8;
 562         default:
 563                 BUG();
 564                 return 0;       /* shut up gcc */
 565         }
 566 }
 567
 568 static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
 569 {
 570         struct scsi_disk *sdkp = NULL;
 571
 572         mutex_lock(&sd_ref_mutex);
 573
 574         if (disk->private_data) {
 575                 sdkp = scsi_disk(disk);
 576                 if (scsi_device_get(sdkp->device) == 0)
 577                         get_device(&sdkp->dev);
 578                 else
 579                         sdkp = NULL;
 580         }
 581         mutex_unlock(&sd_ref_mutex);
 582         return sdkp;
 583 }
 584
 585 static void scsi_disk_put(struct scsi_disk *sdkp)
 586 {
 587         struct scsi_device *sdev = sdkp->device;
 588
 589         mutex_lock(&sd_ref_mutex);
 590         put_device(&sdkp->dev);
 591         scsi_device_put(sdev);
 592         mutex_unlock(&sd_ref_mutex);
 593 }
 594
 595 static unsigned char sd_setup_protect_cmnd(struct scsi_cmnd *scmd,
 596                                            unsigned int dix, unsigned int dif)
 597 {
 598         struct bio *bio = scmd->request->bio;
 599         unsigned int prot_op = sd_prot_op(rq_data_dir(scmd->request), dix, dif);
 600         unsigned int protect = 0;
 601
 602         if (dix) {                              /* DIX Type 0, 1, 2, 3 */
 603                 if (bio_integrity_flagged(bio, BIP_IP_CHECKSUM))
 604                         scmd->prot_flags |= SCSI_PROT_IP_CHECKSUM;
 605
 606                 if (bio_integrity_flagged(bio, BIP_CTRL_NOCHECK) == false)
 607                         scmd->prot_flags |= SCSI_PROT_GUARD_CHECK;
 608         }
 609
 610         if (dif != SD_DIF_TYPE3_PROTECTION) {   /* DIX/DIF Type 0, 1, 2 */
 611                 scmd->prot_flags |= SCSI_PROT_REF_INCREMENT;
 612
 613                 if (bio_integrity_flagged(bio, BIP_CTRL_NOCHECK) == false)
 614                         scmd->prot_flags |= SCSI_PROT_REF_CHECK;
 615         }
 616
 617         if (dif) {                              /* DIX/DIF Type 1, 2, 3 */
 618                 scmd->prot_flags |= SCSI_PROT_TRANSFER_PI;
 619
 620                 if (bio_integrity_flagged(bio, BIP_DISK_NOCHECK))
 621                         protect = 3 << 5;       /* Disable target PI checking */
 622                 else
 623                         protect = 1 << 5;       /* Enable target PI checking */
 624         }
 625
 626         scsi_set_prot_op(scmd, prot_op);
 627         scsi_set_prot_type(scmd, dif);
 628         scmd->prot_flags &= sd_prot_flag_mask(prot_op);
 629
 630         return protect;
 631 }
 632
 633 static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
 634 {
 635         struct request_queue *q = sdkp->disk->queue;
 636         unsigned int logical_block_size = sdkp->device->sector_size;
 637         unsigned int max_blocks = 0;
 638
 639         q->limits.discard_zeroes_data = 0;
 640         q->limits.discard_alignment = sdkp->unmap_alignment *
 641                 logical_block_size;
 642         q->limits.discard_granularity =
 643                 max(sdkp->physical_block_size,
 644                     sdkp->unmap_granularity * logical_block_size);
 645
 646         sdkp->provisioning_mode = mode;
 647
 648         switch (mode) {
 649
 650         case SD_LBP_DISABLE:
 651                 blk_queue_max_discard_sectors(q, 0);
 652                 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
 653                 return;
 654
 655         case SD_LBP_UNMAP:
 656                 max_blocks = min_not_zero(sdkp->max_unmap_blocks,
 657                                           (u32)SD_MAX_WS16_BLOCKS);
 658                 break;
 659
 660         case SD_LBP_WS16:
 661                 max_blocks = min_not_zero(sdkp->max_ws_blocks,
 662                                           (u32)SD_MAX_WS16_BLOCKS);
 663                 q->limits.discard_zeroes_data = sdkp->lbprz;
 664                 break;
 665
 666         case SD_LBP_WS10:
 667                 max_blocks = min_not_zero(sdkp->max_ws_blocks,
 668                                           (u32)SD_MAX_WS10_BLOCKS);
 669                 q->limits.discard_zeroes_data = sdkp->lbprz;
 670                 break;
 671
 672         case SD_LBP_ZERO:
 673                 max_blocks = min_not_zero(sdkp->max_ws_blocks,
 674                                           (u32)SD_MAX_WS10_BLOCKS);
 675                 q->limits.discard_zeroes_data = 1;
 676                 break;
 677         }
 678
 679         blk_queue_max_discard_sectors(q, max_blocks * (logical_block_size >> 9));
 680         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
 681 }
 682
 683 /**
 684  * sd_setup_discard_cmnd - unmap blocks on thinly provisioned device
 685  * @sdp: scsi device to operate one
 686  * @rq: Request to prepare
 687  *
 688  * Will issue either UNMAP or WRITE SAME(16) depending on preference
 689  * indicated by target device.
 690  **/
 691 static int sd_setup_discard_cmnd(struct scsi_cmnd *cmd)
 692 {
 693         struct request *rq = cmd->request;
 694         struct scsi_device *sdp = cmd->device;
 695         struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
 696         sector_t sector = blk_rq_pos(rq);
 697         unsigned int nr_sectors = blk_rq_sectors(rq);
 698         unsigned int nr_bytes = blk_rq_bytes(rq);
 699         unsigned int len;
 700         int ret;
 701         char *buf;
 702         struct page *page;
 703
 704         sector >>= ilog2(sdp->sector_size) - 9;
 705         nr_sectors >>= ilog2(sdp->sector_size) - 9;
 706
 707         page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
 708         if (!page)
 709                 return BLKPREP_DEFER;
 710
 711         switch (sdkp->provisioning_mode) {
 712         case SD_LBP_UNMAP:
 713                 buf = page_address(page);
 714
 715                 cmd->cmd_len = 10;
 716                 cmd->cmnd[0] = UNMAP;
 717                 cmd->cmnd[8] = 24;
 718
 719                 put_unaligned_be16(6 + 16, &buf[0]);
 720                 put_unaligned_be16(16, &buf[2]);
 721                 put_unaligned_be64(sector, &buf[8]);
 722                 put_unaligned_be32(nr_sectors, &buf[16]);
 723
 724                 len = 24;
 725                 break;
 726
 727         case SD_LBP_WS16:
 728                 cmd->cmd_len = 16;
 729                 cmd->cmnd[0] = WRITE_SAME_16;
 730                 cmd->cmnd[1] = 0x8; /* UNMAP */
 731                 put_unaligned_be64(sector, &cmd->cmnd[2]);
 732                 put_unaligned_be32(nr_sectors, &cmd->cmnd[10]);
 733
 734                 len = sdkp->device->sector_size;
 735                 break;
 736
 737         case SD_LBP_WS10:
 738         case SD_LBP_ZERO:
 739                 cmd->cmd_len = 10;
 740                 cmd->cmnd[0] = WRITE_SAME;
 741                 if (sdkp->provisioning_mode == SD_LBP_WS10)
 742                         cmd->cmnd[1] = 0x8; /* UNMAP */
 743                 put_unaligned_be32(sector, &cmd->cmnd[2]);
 744                 put_unaligned_be16(nr_sectors, &cmd->cmnd[7]);
 745
 746                 len = sdkp->device->sector_size;
 747                 break;
 748
 749         default:
 750                 ret = BLKPREP_KILL;
 751                 goto out;
 752         }
 753
 754         rq->completion_data = page;
 755         rq->timeout = SD_TIMEOUT;
 756
 757         cmd->transfersize = len;
 758         cmd->allowed = SD_MAX_RETRIES;
 759
 760         /*
 761          * Initially __data_len is set to the amount of data that needs to be
 762          * transferred to the target. This amount depends on whether WRITE SAME
 763          * or UNMAP is being used. After the scatterlist has been mapped by
 764          * scsi_init_io() we set __data_len to the size of the area to be
 765          * discarded on disk. This allows us to report completion on the full
 766          * amount of blocks described by the request.
 767          */
 768         blk_add_request_payload(rq, page, len);
 769         ret = scsi_init_io(cmd);
 770         rq->__data_len = nr_bytes;
 771
 772 out:
 773         if (ret != BLKPREP_OK)
 774                 __free_page(page);
 775         return ret;
 776 }
 777
 778 static void sd_config_write_same(struct scsi_disk *sdkp)
 779 {
 780         struct request_queue *q = sdkp->disk->queue;
 781         unsigned int logical_block_size = sdkp->device->sector_size;
 782
 783         if (sdkp->device->no_write_same) {
 784                 sdkp->max_ws_blocks = 0;
 785                 goto out;
 786         }
 787
 788         /* Some devices can not handle block counts above 0xffff despite
 789          * supporting WRITE SAME(16). Consequently we default to 64k
 790          * blocks per I/O unless the device explicitly advertises a
 791          * bigger limit.
 792          */
 793         if (sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS)
 794                 sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
 795                                                    (u32)SD_MAX_WS16_BLOCKS);
 796         else if (sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes)
 797                 sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
 798                                                    (u32)SD_MAX_WS10_BLOCKS);
 799         else {
 800                 sdkp->device->no_write_same = 1;
 801                 sdkp->max_ws_blocks = 0;
 802         }
 803
 804 out:
 805         blk_queue_max_write_same_sectors(q, sdkp->max_ws_blocks *
 806                                          (logical_block_size >> 9));
 807 }
 808
 809 /**
 810  * sd_setup_write_same_cmnd - write the same data to multiple blocks
 811  * @cmd: command to prepare
 812  *
 813  * Will issue either WRITE SAME(10) or WRITE SAME(16) depending on
 814  * preference indicated by target device.
 815  **/
 816 static int sd_setup_write_same_cmnd(struct scsi_cmnd *cmd)
 817 {
 818         struct request *rq = cmd->request;
 819         struct scsi_device *sdp = cmd->device;
 820         struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
 821         struct bio *bio = rq->bio;
 822         sector_t sector = blk_rq_pos(rq);
 823         unsigned int nr_sectors = blk_rq_sectors(rq);
 824         unsigned int nr_bytes = blk_rq_bytes(rq);
 825         int ret;
 826
 827         if (sdkp->device->no_write_same)
 828                 return BLKPREP_KILL;
 829
 830         BUG_ON(bio_offset(bio) || bio_iovec(bio).bv_len != sdp->sector_size);
 831
 832         sector >>= ilog2(sdp->sector_size) - 9;
 833         nr_sectors >>= ilog2(sdp->sector_size) - 9;
 834
 835         rq->timeout = SD_WRITE_SAME_TIMEOUT;
 836
 837         if (sdkp->ws16 || sector > 0xffffffff || nr_sectors > 0xffff) {
 838                 cmd->cmd_len = 16;
 839                 cmd->cmnd[0] = WRITE_SAME_16;
 840                 put_unaligned_be64(sector, &cmd->cmnd[2]);
 841                 put_unaligned_be32(nr_sectors, &cmd->cmnd[10]);
 842         } else {
 843                 cmd->cmd_len = 10;
 844                 cmd->cmnd[0] = WRITE_SAME;
 845                 put_unaligned_be32(sector, &cmd->cmnd[2]);
 846                 put_unaligned_be16(nr_sectors, &cmd->cmnd[7]);
 847         }
 848
 849         cmd->transfersize = sdp->sector_size;
 850         cmd->allowed = SD_MAX_RETRIES;
 851
 852         /*
 853          * For WRITE_SAME the data transferred in the DATA IN buffer is
 854          * different from the amount of data actually written to the target.
 855          *
 856          * We set up __data_len to the amount of data transferred from the
 857          * DATA IN buffer so that blk_rq_map_sg set up the proper S/G list
 858          * to transfer a single sector of data first, but then reset it to
 859          * the amount of data to be written right after so that the I/O path
 860          * knows how much to actually write.
 861          */
 862         rq->__data_len = sdp->sector_size;
 863         ret = scsi_init_io(cmd);
 864         rq->__data_len = nr_bytes;
 865         return ret;
 866 }
 867
 868 static int sd_setup_flush_cmnd(struct scsi_cmnd *cmd)
 869 {
 870         struct request *rq = cmd->request;
 871
 872         /* flush requests don't perform I/O, zero the S/G table */
 873         memset(&cmd->sdb, 0, sizeof(cmd->sdb));
 874
 875         cmd->cmnd[0] = SYNCHRONIZE_CACHE;
 876         cmd->cmd_len = 10;
 877         cmd->transfersize = 0;
 878         cmd->allowed = SD_MAX_RETRIES;
 879
 880         rq->timeout = rq->q->rq_timeout * SD_FLUSH_TIMEOUT_MULTIPLIER;
 881         return BLKPREP_OK;
 882 }
 883
 884 static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
 885 {
 886         struct request *rq = SCpnt->request;
 887         struct scsi_device *sdp = SCpnt->device;
 888         struct gendisk *disk = rq->rq_disk;
 889         struct scsi_disk *sdkp;
 890         sector_t block = blk_rq_pos(rq);
 891         sector_t threshold;
 892         unsigned int this_count = blk_rq_sectors(rq);
 893         unsigned int dif, dix;
 894         int ret;
 895         unsigned char protect;
 896
 897         ret = scsi_init_io(SCpnt);
 898         if (ret != BLKPREP_OK)
 899                 goto out;
 900         SCpnt = rq->special;
 901         sdkp = scsi_disk(disk);
 902
 903         /* from here on until we're complete, any goto out
 904          * is used for a killable error condition */
 905         ret = BLKPREP_KILL;
 906
 907         SCSI_LOG_HLQUEUE(1,
 908                 scmd_printk(KERN_INFO, SCpnt,
 909                         "%s: block=%llu, count=%d\n",
 910                         __func__, (unsigned long long)block, this_count));
 911
 912         if (!sdp || !scsi_device_online(sdp) ||
 913             block + blk_rq_sectors(rq) > get_capacity(disk)) {
 914                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 915                                                 "Finishing %u sectors\n",
 916                                                 blk_rq_sectors(rq)));
 917                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 918                                                 "Retry with 0x%p\n", SCpnt));
 919                 goto out;
 920         }
 921
 922         if (sdp->changed) {
 923                 /*
 924                  * quietly refuse to do anything to a changed disc until
 925                  * the changed bit has been reset
 926                  */
 927                 /* printk("SCSI disk has been changed or is not present. Prohibiting further I/O.\n"); */
 928                 goto out;
 929         }
 930
 931         /*
 932          * Some SD card readers can't handle multi-sector accesses which touch
 933          * the last one or two hardware sectors.  Split accesses as needed.
 934          */
 935         threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
 936                 (sdp->sector_size / 512);
 937
 938         if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
 939                 if (block < threshold) {
 940                         /* Access up to the threshold but not beyond */
 941                         this_count = threshold - block;
 942                 } else {
 943                         /* Access only a single hardware sector */
 944                         this_count = sdp->sector_size / 512;
 945                 }
 946         }
 947
 948         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
 949                                         (unsigned long long)block));
 950
 951         /*
 952          * If we have a 1K hardware sectorsize, prevent access to single
 953          * 512 byte sectors.  In theory we could handle this - in fact
 954          * the scsi cdrom driver must be able to handle this because
 955          * we typically use 1K blocksizes, and cdroms typically have
 956          * 2K hardware sectorsizes.  Of course, things are simpler
 957          * with the cdrom, since it is read-only.  For performance
 958          * reasons, the filesystems should be able to handle this
 959          * and not force the scsi disk driver to use bounce buffers
 960          * for this.
 961          */
 962         if (sdp->sector_size == 1024) {
 963                 if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
 964                         scmd_printk(KERN_ERR, SCpnt,
 965                                     "Bad block number requested\n");
 966                         goto out;
 967                 } else {
 968                         block = block >> 1;
 969                         this_count = this_count >> 1;
 970                 }
 971         }
 972         if (sdp->sector_size == 2048) {
 973                 if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
 974                         scmd_printk(KERN_ERR, SCpnt,
 975                                     "Bad block number requested\n");
 976                         goto out;
 977                 } else {
 978                         block = block >> 2;
 979                         this_count = this_count >> 2;
 980                 }
 981         }
 982         if (sdp->sector_size == 4096) {
 983                 if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
 984                         scmd_printk(KERN_ERR, SCpnt,
 985                                     "Bad block number requested\n");
 986                         goto out;
 987                 } else {
 988                         block = block >> 3;
 989                         this_count = this_count >> 3;
 990                 }
 991         }
 992         if (rq_data_dir(rq) == WRITE) {
 993                 SCpnt->cmnd[0] = WRITE_6;
 994
 995                 if (blk_integrity_rq(rq))
 996                         sd_dif_prepare(SCpnt);
 997
 998         } else if (rq_data_dir(rq) == READ) {
 999                 SCpnt->cmnd[0] = READ_6;
1000         } else {
1001                 scmd_printk(KERN_ERR, SCpnt, "Unknown command %llx\n", (unsigned long long) rq->cmd_flags);
1002                 goto out;
1003         }
1004
1005         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
1006                                         "%s %d/%u 512 byte blocks.\n",
1007                                         (rq_data_dir(rq) == WRITE) ?
1008                                         "writing" : "reading", this_count,
1009                                         blk_rq_sectors(rq)));
1010
1011         dix = scsi_prot_sg_count(SCpnt);
1012         dif = scsi_host_dif_capable(SCpnt->device->host, sdkp->protection_type);
1013
1014         if (dif || dix)
1015                 protect = sd_setup_protect_cmnd(SCpnt, dix, dif);
1016         else
1017                 protect = 0;
1018
1019         if (protect && sdkp->protection_type == SD_DIF_TYPE2_PROTECTION) {
1020                 SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
1021
1022                 if (unlikely(SCpnt->cmnd == NULL)) {
1023                         ret = BLKPREP_DEFER;
1024                         goto out;
1025                 }
1026
1027                 SCpnt->cmd_len = SD_EXT_CDB_SIZE;
1028                 memset(SCpnt->cmnd, 0, SCpnt->cmd_len);
1029                 SCpnt->cmnd[0] = VARIABLE_LENGTH_CMD;
1030                 SCpnt->cmnd[7] = 0x18;
1031                 SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
1032                 SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
1033
1034                 /* LBA */
1035                 SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
1036                 SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
1037                 SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
1038                 SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
1039                 SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
1040                 SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
1041                 SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
1042                 SCpnt->cmnd[19] = (unsigned char) block & 0xff;
1043
1044                 /* Expected Indirect LBA */
1045                 SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
1046                 SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
1047                 SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
1048                 SCpnt->cmnd[23] = (unsigned char) block & 0xff;
1049
1050                 /* Transfer length */
1051                 SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
1052                 SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
1053                 SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
1054                 SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
1055         } else if (sdp->use_16_for_rw || (this_count > 0xffff)) {
1056                 SCpnt->cmnd[0] += READ_16 - READ_6;
1057                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
1058                 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
1059                 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
1060                 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
1061                 SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
1062                 SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
1063                 SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
1064                 SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
1065                 SCpnt->cmnd[9] = (unsigned char) block & 0xff;
1066                 SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
1067                 SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
1068                 SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
1069                 SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
1070                 SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
1071         } else if ((this_count > 0xff) || (block > 0x1fffff) ||
1072                    scsi_device_protection(SCpnt->device) ||
1073                    SCpnt->device->use_10_for_rw) {
1074                 SCpnt->cmnd[0] += READ_10 - READ_6;
1075                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
1076                 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
1077                 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
1078                 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
1079                 SCpnt->cmnd[5] = (unsigned char) block & 0xff;
1080                 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
1081                 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
1082                 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
1083         } else {
1084                 if (unlikely(rq->cmd_flags & REQ_FUA)) {
1085                         /*
1086                          * This happens only if this drive failed
1087                          * 10byte rw command with ILLEGAL_REQUEST
1088                          * during operation and thus turned off
1089                          * use_10_for_rw.
1090                          */
1091                         scmd_printk(KERN_ERR, SCpnt,
1092                                     "FUA write on READ/WRITE(6) drive\n");
1093                         goto out;
1094                 }
1095
1096                 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
1097                 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
1098                 SCpnt->cmnd[3] = (unsigned char) block & 0xff;
1099                 SCpnt->cmnd[4] = (unsigned char) this_count;
1100                 SCpnt->cmnd[5] = 0;
1101         }
1102         SCpnt->sdb.length = this_count * sdp->sector_size;
1103
1104         /*
1105          * We shouldn't disconnect in the middle of a sector, so with a dumb
1106          * host adapter, it's safe to assume that we can at least transfer
1107          * this many bytes between each connect / disconnect.
1108          */
1109         SCpnt->transfersize = sdp->sector_size;
1110         SCpnt->underflow = this_count << 9;
1111         SCpnt->allowed = SD_MAX_RETRIES;
1112
1113         /*
1114          * This indicates that the command is ready from our end to be
1115          * queued.
1116          */
1117         ret = BLKPREP_OK;
1118  out:
1119         return ret;
1120 }
1121
1122 static int sd_init_command(struct scsi_cmnd *cmd)
1123 {
1124         struct request *rq = cmd->request;
1125
1126         if (rq->cmd_flags & REQ_DISCARD)
1127                 return sd_setup_discard_cmnd(cmd);
1128         else if (rq->cmd_flags & REQ_WRITE_SAME)
1129                 return sd_setup_write_same_cmnd(cmd);
1130         else if (rq->cmd_flags & REQ_FLUSH)
1131                 return sd_setup_flush_cmnd(cmd);
1132         else
1133                 return sd_setup_read_write_cmnd(cmd);
1134 }
1135
1136 static void sd_uninit_command(struct scsi_cmnd *SCpnt)
1137 {
1138         struct request *rq = SCpnt->request;
1139
1140         if (rq->cmd_flags & REQ_DISCARD)
1141                 __free_page(rq->completion_data);
1142
1143         if (SCpnt->cmnd != rq->cmd) {
1144                 mempool_free(SCpnt->cmnd, sd_cdb_pool);
1145                 SCpnt->cmnd = NULL;
1146                 SCpnt->cmd_len = 0;
1147         }
1148 }
1149
1150 /**
1151  *      sd_open - open a scsi disk device
1152  *      @inode: only i_rdev member may be used
1153  *      @filp: only f_mode and f_flags may be used
1154  *
1155  *      Returns 0 if successful. Returns a negated errno value in case
1156  *      of error.
1157  *
1158  *      Note: This can be called from a user context (e.g. fsck(1) )
1159  *      or from within the kernel (e.g. as a result of a mount(1) ).
1160  *      In the latter case @inode and @filp carry an abridged amount
1161  *      of information as noted above.
1162  *
1163  *      Locking: called with bdev->bd_mutex held.
1164  **/
1165 static int sd_open(struct block_device *bdev, fmode_t mode)
1166 {
1167         struct scsi_disk *sdkp = scsi_disk_get(bdev->bd_disk);
1168         struct scsi_device *sdev;
1169         int retval;
1170
1171         if (!sdkp)
1172                 return -ENXIO;
1173
1174         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
1175
1176         sdev = sdkp->device;
1177
1178         /*
1179          * If the device is in error recovery, wait until it is done.
1180          * If the device is offline, then disallow any access to it.
1181          */
1182         retval = -ENXIO;
1183         if (!scsi_block_when_processing_errors(sdev))
1184                 goto error_out;
1185
1186         if (sdev->removable || sdkp->write_prot)
1187                 check_disk_change(bdev);
1188
1189         /*
1190          * If the drive is empty, just let the open fail.
1191          */
1192         retval = -ENOMEDIUM;
1193         if (sdev->removable && !sdkp->media_present && !(mode & FMODE_NDELAY))
1194                 goto error_out;
1195
1196         /*
1197          * If the device has the write protect tab set, have the open fail
1198          * if the user expects to be able to write to the thing.
1199          */
1200         retval = -EROFS;
1201         if (sdkp->write_prot && (mode & FMODE_WRITE))
1202                 goto error_out;
1203
1204         /*
1205          * It is possible that the disk changing stuff resulted in
1206          * the device being taken offline.  If this is the case,
1207          * report this to the user, and don't pretend that the
1208          * open actually succeeded.
1209          */
1210         retval = -ENXIO;
1211         if (!scsi_device_online(sdev))
1212                 goto error_out;
1213
1214         if ((atomic_inc_return(&sdkp->openers) == 1) && sdev->removable) {
1215                 if (scsi_block_when_processing_errors(sdev))
1216                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
1217         }
1218
1219         return 0;
1220
1221 error_out:
1222         scsi_disk_put(sdkp);
1223         return retval;
1224 }
1225
1226 /**
1227  *      sd_release - invoked when the (last) close(2) is called on this
1228  *      scsi disk.
1229  *      @inode: only i_rdev member may be used
1230  *      @filp: only f_mode and f_flags may be used
1231  *
1232  *      Returns 0.
1233  *
1234  *      Note: may block (uninterruptible) if error recovery is underway
1235  *      on this disk.
1236  *
1237  *      Locking: called with bdev->bd_mutex held.
1238  **/
1239 static void sd_release(struct gendisk *disk, fmode_t mode)
1240 {
1241         struct scsi_disk *sdkp = scsi_disk(disk);
1242         struct scsi_device *sdev = sdkp->device;
1243
1244         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
1245
1246         if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
1247                 if (scsi_block_when_processing_errors(sdev))
1248                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
1249         }
1250
1251         /*
1252          * XXX and what if there are packets in flight and this close()
1253          * XXX is followed by a "rmmod sd_mod"?
1254          */
1255
1256         scsi_disk_put(sdkp);
1257 }
1258
1259 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1260 {
1261         struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
1262         struct scsi_device *sdp = sdkp->device;
1263         struct Scsi_Host *host = sdp->host;
1264         int diskinfo[4];
1265
1266         /* default to most commonly used values */
1267         diskinfo[0] = 0x40;     /* 1 << 6 */
1268         diskinfo[1] = 0x20;     /* 1 << 5 */
1269         diskinfo[2] = sdkp->capacity >> 11;
1270
1271         /* override with calculated, extended default, or driver values */
1272         if (host->hostt->bios_param)
1273                 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
1274         else
1275                 scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
1276
1277         geo->heads = diskinfo[0];
1278         geo->sectors = diskinfo[1];
1279         geo->cylinders = diskinfo[2];
1280         return 0;
1281 }
1282
1283 /**
1284  *      sd_ioctl - process an ioctl
1285  *      @inode: only i_rdev/i_bdev members may be used
1286  *      @filp: only f_mode and f_flags may be used
1287  *      @cmd: ioctl command number
1288  *      @arg: this is third argument given to ioctl(2) system call.
1289  *      Often contains a pointer.
1290  *
1291  *      Returns 0 if successful (some ioctls return positive numbers on
1292  *      success as well). Returns a negated errno value in case of error.
1293  *
1294  *      Note: most ioctls are forward onto the block subsystem or further
1295  *      down in the scsi subsystem.
1296  **/
1297 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
1298                     unsigned int cmd, unsigned long arg)
1299 {
1300         struct gendisk *disk = bdev->bd_disk;
1301         struct scsi_disk *sdkp = scsi_disk(disk);
1302         struct scsi_device *sdp = sdkp->device;
1303         void __user *p = (void __user *)arg;
1304         int error;
1305
1306         SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
1307                                     "cmd=0x%x\n", disk->disk_name, cmd));
1308
1309         error = scsi_verify_blk_ioctl(bdev, cmd);
1310         if (error < 0)
1311                 return error;
1312
1313         /*
1314          * If we are in the middle of error recovery, don't let anyone
1315          * else try and use this device.  Also, if error recovery fails, it
1316          * may try and take the device offline, in which case all further
1317          * access to the device is prohibited.
1318          */
1319         error = scsi_ioctl_block_when_processing_errors(sdp, cmd,
1320                         (mode & FMODE_NDELAY) != 0);
1321         if (error)
1322                 goto out;
1323
1324         /*
1325          * Send SCSI addressing ioctls directly to mid level, send other
1326          * ioctls to block level and then onto mid level if they can't be
1327          * resolved.
1328          */
1329         switch (cmd) {
1330                 case SCSI_IOCTL_GET_IDLUN:
1331                 case SCSI_IOCTL_GET_BUS_NUMBER:
1332                         error = scsi_ioctl(sdp, cmd, p);
1333                         break;
1334                 default:
1335                         error = scsi_cmd_blk_ioctl(bdev, mode, cmd, p);
1336                         if (error != -ENOTTY)
1337                                 break;
1338                         error = scsi_ioctl(sdp, cmd, p);
1339                         break;
1340         }
1341 out:
1342         return error;
1343 }
1344
1345 static void set_media_not_present(struct scsi_disk *sdkp)
1346 {
1347         if (sdkp->media_present)
1348                 sdkp->device->changed = 1;
1349
1350         if (sdkp->device->removable) {
1351                 sdkp->media_present = 0;
1352                 sdkp->capacity = 0;
1353         }
1354 }
1355
1356 static int media_not_present(struct scsi_disk *sdkp,
1357                              struct scsi_sense_hdr *sshdr)
1358 {
1359         if (!scsi_sense_valid(sshdr))
1360                 return 0;
1361
1362         /* not invoked for commands that could return deferred errors */
1363         switch (sshdr->sense_key) {
1364         case UNIT_ATTENTION:
1365         case NOT_READY:
1366                 /* medium not present */
1367                 if (sshdr->asc == 0x3A) {
1368                         set_media_not_present(sdkp);
1369                         return 1;
1370                 }
1371         }
1372         return 0;
1373 }
1374
1375 /**
1376  *      sd_check_events - check media events
1377  *      @disk: kernel device descriptor
1378  *      @clearing: disk events currently being cleared
1379  *
1380  *      Returns mask of DISK_EVENT_*.
1381  *
1382  *      Note: this function is invoked from the block subsystem.
1383  **/
1384 static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
1385 {
1386         struct scsi_disk *sdkp = scsi_disk(disk);
1387         struct scsi_device *sdp = sdkp->device;
1388         struct scsi_sense_hdr *sshdr = NULL;
1389         int retval;
1390
1391         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
1392
1393         /*
1394          * If the device is offline, don't send any commands - just pretend as
1395          * if the command failed.  If the device ever comes back online, we
1396          * can deal with it then.  It is only because of unrecoverable errors
1397          * that we would ever take a device offline in the first place.
1398          */
1399         if (!scsi_device_online(sdp)) {
1400                 set_media_not_present(sdkp);
1401                 goto out;
1402         }
1403
1404         /*
1405          * Using TEST_UNIT_READY enables differentiation between drive with
1406          * no cartridge loaded - NOT READY, drive with changed cartridge -
1407          * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
1408          *
1409          * Drives that auto spin down. eg iomega jaz 1G, will be started
1410          * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
1411          * sd_revalidate() is called.
1412          */
1413         retval = -ENODEV;
1414
1415         if (scsi_block_when_processing_errors(sdp)) {
1416                 sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
1417                 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
1418                                               sshdr);
1419         }
1420
1421         /* failed to execute TUR, assume media not present */
1422         if (host_byte(retval)) {
1423                 set_media_not_present(sdkp);
1424                 goto out;
1425         }
1426
1427         if (media_not_present(sdkp, sshdr))
1428                 goto out;
1429
1430         /*
1431          * For removable scsi disk we have to recognise the presence
1432          * of a disk in the drive.
1433          */
1434         if (!sdkp->media_present)
1435                 sdp->changed = 1;
1436         sdkp->media_present = 1;
1437 out:
1438         /*
1439          * sdp->changed is set under the following conditions:
1440          *
1441          *      Medium present state has changed in either direction.
1442          *      Device has indicated UNIT_ATTENTION.
1443          */
1444         kfree(sshdr);
1445         retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
1446         sdp->changed = 0;
1447         return retval;
1448 }
1449
1450 static int sd_sync_cache(struct scsi_disk *sdkp)
1451 {
1452         int retries, res;
1453         struct scsi_device *sdp = sdkp->device;
1454         const int timeout = sdp->request_queue->rq_timeout
1455                 * SD_FLUSH_TIMEOUT_MULTIPLIER;
1456         struct scsi_sense_hdr sshdr;
1457
1458         if (!scsi_device_online(sdp))
1459                 return -ENODEV;
1460
1461         for (retries = 3; retries > 0; --retries) {
1462                 unsigned char cmd[10] = { 0 };
1463
1464                 cmd[0] = SYNCHRONIZE_CACHE;
1465                 /*
1466                  * Leave the rest of the command zero to indicate
1467                  * flush everything.
1468                  */
1469                 res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0,
1470                                              &sshdr, timeout, SD_MAX_RETRIES,
1471                                              NULL, REQ_PM);
1472                 if (res == 0)
1473                         break;
1474         }
1475
1476         if (res) {
1477                 sd_print_result(sdkp, "Synchronize Cache(10) failed", res);
1478
1479                 if (driver_byte(res) & DRIVER_SENSE)
1480                         sd_print_sense_hdr(sdkp, &sshdr);
1481                 /* we need to evaluate the error return  */
1482                 if (scsi_sense_valid(&sshdr) &&
1483                         (sshdr.asc == 0x3a ||   /* medium not present */
1484                          sshdr.asc == 0x20))    /* invalid command */
1485                                 /* this is no error here */
1486                                 return 0;
1487
1488                 switch (host_byte(res)) {
1489                 /* ignore errors due to racing a disconnection */
1490                 case DID_BAD_TARGET:
1491                 case DID_NO_CONNECT:
1492                         return 0;
1493                 /* signal the upper layer it might try again */
1494                 case DID_BUS_BUSY:
1495                 case DID_IMM_RETRY:
1496                 case DID_REQUEUE:
1497                 case DID_SOFT_ERROR:
1498                         return -EBUSY;
1499                 default:
1500                         return -EIO;
1501                 }
1502         }
1503         return 0;
1504 }
1505
1506 static void sd_rescan(struct device *dev)
1507 {
1508         struct scsi_disk *sdkp = dev_get_drvdata(dev);
1509
1510         revalidate_disk(sdkp->disk);
1511 }
1512
1513
1514 #ifdef CONFIG_COMPAT
1515 /*
1516  * This gets directly called from VFS. When the ioctl
1517  * is not recognized we go back to the other translation paths.
1518  */
1519 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
1520                            unsigned int cmd, unsigned long arg)
1521 {
1522         struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1523         int error;
1524
1525         error = scsi_ioctl_block_when_processing_errors(sdev, cmd,
1526                         (mode & FMODE_NDELAY) != 0);
1527         if (error)
1528                 return error;
1529
1530         /*
1531          * Let the static ioctl translation table take care of it.
1532          */
1533         if (!sdev->host->hostt->compat_ioctl)
1534                 return -ENOIOCTLCMD;
1535         return sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
1536 }
1537 #endif
1538
1539 static const struct block_device_operations sd_fops = {
1540         .owner                  = THIS_MODULE,
1541         .open                   = sd_open,
1542         .release                = sd_release,
1543         .ioctl                  = sd_ioctl,
1544         .getgeo                 = sd_getgeo,
1545 #ifdef CONFIG_COMPAT
1546         .compat_ioctl           = sd_compat_ioctl,
1547 #endif
1548         .check_events           = sd_check_events,
1549         .revalidate_disk        = sd_revalidate_disk,
1550         .unlock_native_capacity = sd_unlock_native_capacity,
1551 };
1552
1553 /**
1554  *      sd_eh_action - error handling callback
1555  *      @scmd:          sd-issued command that has failed
1556  *      @eh_disp:       The recovery disposition suggested by the midlayer
1557  *
1558  *      This function is called by the SCSI midlayer upon completion of an
1559  *      error test command (currently TEST UNIT READY). The result of sending
1560  *      the eh command is passed in eh_disp.  We're looking for devices that
1561  *      fail medium access commands but are OK with non access commands like
1562  *      test unit ready (so wrongly see the device as having a successful
1563  *      recovery)
1564  **/
1565 static int sd_eh_action(struct scsi_cmnd *scmd, int eh_disp)
1566 {
1567         struct scsi_disk *sdkp = scsi_disk(scmd->request->rq_disk);
1568
1569         if (!scsi_device_online(scmd->device) ||
1570             !scsi_medium_access_command(scmd) ||
1571             host_byte(scmd->result) != DID_TIME_OUT ||
1572             eh_disp != SUCCESS)
1573                 return eh_disp;
1574
1575         /*
1576          * The device has timed out executing a medium access command.
1577          * However, the TEST UNIT READY command sent during error
1578          * handling completed successfully. Either the device is in the
1579          * process of recovering or has it suffered an internal failure
1580          * that prevents access to the storage medium.
1581          */
1582         sdkp->medium_access_timed_out++;
1583
1584         /*
1585          * If the device keeps failing read/write commands but TEST UNIT
1586          * READY always completes successfully we assume that medium
1587          * access is no longer possible and take the device offline.
1588          */
1589         if (sdkp->medium_access_timed_out >= sdkp->max_medium_access_timeouts) {
1590                 scmd_printk(KERN_ERR, scmd,
1591                             "Medium access timeout failure. Offlining disk!\n");
1592                 scsi_device_set_state(scmd->device, SDEV_OFFLINE);
1593
1594                 return FAILED;
1595         }
1596
1597         return eh_disp;
1598 }
1599
1600 static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
1601 {
1602         u64 start_lba = blk_rq_pos(scmd->request);
1603         u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
1604         u64 factor = scmd->device->sector_size / 512;
1605         u64 bad_lba;
1606         int info_valid;
1607         /*
1608          * resid is optional but mostly filled in.  When it's unused,
1609          * its value is zero, so we assume the whole buffer transferred
1610          */
1611         unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
1612         unsigned int good_bytes;
1613
1614         if (scmd->request->cmd_type != REQ_TYPE_FS)
1615                 return 0;
1616
1617         info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
1618                                              SCSI_SENSE_BUFFERSIZE,
1619                                              &bad_lba);
1620         if (!info_valid)
1621                 return 0;
1622
1623         if (scsi_bufflen(scmd) <= scmd->device->sector_size)
1624                 return 0;
1625
1626         /* be careful ... don't want any overflows */
1627         do_div(start_lba, factor);
1628         do_div(end_lba, factor);
1629
1630         /* The bad lba was reported incorrectly, we have no idea where
1631          * the error is.
1632          */
1633         if (bad_lba < start_lba  || bad_lba >= end_lba)
1634                 return 0;
1635
1636         /* This computation should always be done in terms of
1637          * the resolution of the device's medium.
1638          */
1639         good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
1640         return min(good_bytes, transferred);
1641 }
1642
1643 /**
1644  *      sd_done - bottom half handler: called when the lower level
1645  *      driver has completed (successfully or otherwise) a scsi command.
1646  *      @SCpnt: mid-level's per command structure.
1647  *
1648  *      Note: potentially run from within an ISR. Must not block.
1649  **/
1650 static int sd_done(struct scsi_cmnd *SCpnt)
1651 {
1652         int result = SCpnt->result;
1653         unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
1654         struct scsi_sense_hdr sshdr;
1655         struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
1656         struct request *req = SCpnt->request;
1657         int sense_valid = 0;
1658         int sense_deferred = 0;
1659         unsigned char op = SCpnt->cmnd[0];
1660         unsigned char unmap = SCpnt->cmnd[1] & 8;
1661
1662         if (req->cmd_flags & REQ_DISCARD || req->cmd_flags & REQ_WRITE_SAME) {
1663                 if (!result) {
1664                         good_bytes = blk_rq_bytes(req);
1665                         scsi_set_resid(SCpnt, 0);
1666                 } else {
1667                         good_bytes = 0;
1668                         scsi_set_resid(SCpnt, blk_rq_bytes(req));
1669                 }
1670         }
1671
1672         if (result) {
1673                 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
1674                 if (sense_valid)
1675                         sense_deferred = scsi_sense_is_deferred(&sshdr);
1676         }
1677         sdkp->medium_access_timed_out = 0;
1678
1679         if (driver_byte(result) != DRIVER_SENSE &&
1680             (!sense_valid || sense_deferred))
1681                 goto out;
1682
1683         switch (sshdr.sense_key) {
1684         case HARDWARE_ERROR:
1685         case MEDIUM_ERROR:
1686                 good_bytes = sd_completed_bytes(SCpnt);
1687                 break;
1688         case RECOVERED_ERROR:
1689                 good_bytes = scsi_bufflen(SCpnt);
1690                 break;
1691         case NO_SENSE:
1692                 /* This indicates a false check condition, so ignore it.  An
1693                  * unknown amount of data was transferred so treat it as an
1694                  * error.
1695                  */
1696                 SCpnt->result = 0;
1697                 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1698                 break;
1699         case ABORTED_COMMAND:
1700                 if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
1701                         good_bytes = sd_completed_bytes(SCpnt);
1702                 break;
1703         case ILLEGAL_REQUEST:
1704                 if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
1705                         good_bytes = sd_completed_bytes(SCpnt);
1706                 /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
1707                 if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
1708                         switch (op) {
1709                         case UNMAP:
1710                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
1711                                 break;
1712                         case WRITE_SAME_16:
1713                         case WRITE_SAME:
1714                                 if (unmap)
1715                                         sd_config_discard(sdkp, SD_LBP_DISABLE);
1716                                 else {
1717                                         sdkp->device->no_write_same = 1;
1718                                         sd_config_write_same(sdkp);
1719
1720                                         good_bytes = 0;
1721                                         req->__data_len = blk_rq_bytes(req);
1722                                         req->cmd_flags |= REQ_QUIET;
1723                                 }
1724                         }
1725                 }
1726                 break;
1727         default:
1728                 break;
1729         }
1730  out:
1731         SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
1732                                            "sd_done: completed %d of %d bytes\n",
1733                                            good_bytes, scsi_bufflen(SCpnt)));
1734
1735         if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
1736                 sd_dif_complete(SCpnt, good_bytes);
1737
1738         return good_bytes;
1739 }
1740
1741 /*
1742  * spinup disk - called only in sd_revalidate_disk()
1743  */
1744 static void
1745 sd_spinup_disk(struct scsi_disk *sdkp)
1746 {
1747         unsigned char cmd[10];
1748         unsigned long spintime_expire = 0;
1749         int retries, spintime;
1750         unsigned int the_result;
1751         struct scsi_sense_hdr sshdr;
1752         int sense_valid = 0;
1753
1754         spintime = 0;
1755
1756         /* Spin up drives, as required.  Only do this at boot time */
1757         /* Spinup needs to be done for module loads too. */
1758         do {
1759                 retries = 0;
1760
1761                 do {
1762                         cmd[0] = TEST_UNIT_READY;
1763                         memset((void *) &cmd[1], 0, 9);
1764
1765                         the_result = scsi_execute_req(sdkp->device, cmd,
1766                                                       DMA_NONE, NULL, 0,
1767                                                       &sshdr, SD_TIMEOUT,
1768                                                       SD_MAX_RETRIES, NULL);
1769
1770                         /*
1771                          * If the drive has indicated to us that it
1772                          * doesn't have any media in it, don't bother
1773                          * with any more polling.
1774                          */
1775                         if (media_not_present(sdkp, &sshdr))
1776                                 return;
1777
1778                         if (the_result)
1779                                 sense_valid = scsi_sense_valid(&sshdr);
1780                         retries++;
1781                 } while (retries < 3 &&
1782                          (!scsi_status_is_good(the_result) ||
1783                           ((driver_byte(the_result) & DRIVER_SENSE) &&
1784                           sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1785
1786                 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1787                         /* no sense, TUR either succeeded or failed
1788                          * with a status error */
1789                         if(!spintime && !scsi_status_is_good(the_result)) {
1790                                 sd_print_result(sdkp, "Test Unit Ready failed",
1791                                                 the_result);
1792                         }
1793                         break;
1794                 }
1795
1796                 /*
1797                  * The device does not want the automatic start to be issued.
1798                  */
1799                 if (sdkp->device->no_start_on_add)
1800                         break;
1801
1802                 if (sense_valid && sshdr.sense_key == NOT_READY) {
1803                         if (sshdr.asc == 4 && sshdr.ascq == 3)
1804                                 break;  /* manual intervention required */
1805                         if (sshdr.asc == 4 && sshdr.ascq == 0xb)
1806                                 break;  /* standby */
1807                         if (sshdr.asc == 4 && sshdr.ascq == 0xc)
1808                                 break;  /* unavailable */
1809                         /*
1810                          * Issue command to spin up drive when not ready
1811                          */
1812                         if (!spintime) {
1813                                 sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
1814                                 cmd[0] = START_STOP;
1815                                 cmd[1] = 1;     /* Return immediately */
1816                                 memset((void *) &cmd[2], 0, 8);
1817                                 cmd[4] = 1;     /* Start spin cycle */
1818                                 if (sdkp->device->start_stop_pwr_cond)
1819                                         cmd[4] |= 1 << 4;
1820                                 scsi_execute_req(sdkp->device, cmd, DMA_NONE,
1821                                                  NULL, 0, &sshdr,
1822                                                  SD_TIMEOUT, SD_MAX_RETRIES,
1823                                                  NULL);
1824                                 spintime_expire = jiffies + 100 * HZ;
1825                                 spintime = 1;
1826                         }
1827                         /* Wait 1 second for next try */
1828                         msleep(1000);
1829                         printk(".");
1830
1831                 /*
1832                  * Wait for USB flash devices with slow firmware.
1833                  * Yes, this sense key/ASC combination shouldn't
1834                  * occur here.  It's characteristic of these devices.
1835                  */
1836                 } else if (sense_valid &&
1837                                 sshdr.sense_key == UNIT_ATTENTION &&
1838                                 sshdr.asc == 0x28) {
1839                         if (!spintime) {
1840                                 spintime_expire = jiffies + 5 * HZ;
1841                                 spintime = 1;
1842                         }
1843                         /* Wait 1 second for next try */
1844                         msleep(1000);
1845                 } else {
1846                         /* we don't understand the sense code, so it's
1847                          * probably pointless to loop */
1848                         if(!spintime) {
1849                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1850                                 sd_print_sense_hdr(sdkp, &sshdr);
1851                         }
1852                         break;
1853                 }
1854
1855         } while (spintime && time_before_eq(jiffies, spintime_expire));
1856
1857         if (spintime) {
1858                 if (scsi_status_is_good(the_result))
1859                         printk("ready\n");
1860                 else
1861                         printk("not responding...\n");
1862         }
1863 }
1864
1865
1866 /*
1867  * Determine whether disk supports Data Integrity Field.
1868  */
1869 static int sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
1870 {
1871         struct scsi_device *sdp = sdkp->device;
1872         u8 type;
1873         int ret = 0;
1874
1875         if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
1876                 return ret;
1877
1878         type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
1879
1880         if (type > SD_DIF_TYPE3_PROTECTION)
1881                 ret = -ENODEV;
1882         else if (scsi_host_dif_capable(sdp->host, type))
1883                 ret = 1;
1884
1885         if (sdkp->first_scan || type != sdkp->protection_type)
1886                 switch (ret) {
1887                 case -ENODEV:
1888                         sd_printk(KERN_ERR, sdkp, "formatted with unsupported" \
1889                                   " protection type %u. Disabling disk!\n",
1890                                   type);
1891                         break;
1892                 case 1:
1893                         sd_printk(KERN_NOTICE, sdkp,
1894                                   "Enabling DIF Type %u protection\n", type);
1895                         break;
1896                 case 0:
1897                         sd_printk(KERN_NOTICE, sdkp,
1898                                   "Disabling DIF Type %u protection\n", type);
1899                         break;
1900                 }
1901
1902         sdkp->protection_type = type;
1903
1904         return ret;
1905 }
1906
1907 static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
1908                         struct scsi_sense_hdr *sshdr, int sense_valid,
1909                         int the_result)
1910 {
1911         if (driver_byte(the_result) & DRIVER_SENSE)
1912                 sd_print_sense_hdr(sdkp, sshdr);
1913         else
1914                 sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
1915
1916         /*
1917          * Set dirty bit for removable devices if not ready -
1918          * sometimes drives will not report this properly.
1919          */
1920         if (sdp->removable &&
1921             sense_valid && sshdr->sense_key == NOT_READY)
1922                 set_media_not_present(sdkp);
1923
1924         /*
1925          * We used to set media_present to 0 here to indicate no media
1926          * in the drive, but some drives fail read capacity even with
1927          * media present, so we can't do that.
1928          */
1929         sdkp->capacity = 0; /* unknown mapped to zero - as usual */
1930 }
1931
1932 #define RC16_LEN 32
1933 #if RC16_LEN > SD_BUF_SIZE
1934 #error RC16_LEN must not be more than SD_BUF_SIZE
1935 #endif
1936
1937 #define READ_CAPACITY_RETRIES_ON_RESET  10
1938
1939 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
1940                                                 unsigned char *buffer)
1941 {
1942         unsigned char cmd[16];
1943         struct scsi_sense_hdr sshdr;
1944         int sense_valid = 0;
1945         int the_result;
1946         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1947         unsigned int alignment;
1948         unsigned long long lba;
1949         unsigned sector_size;
1950
1951         if (sdp->no_read_capacity_16)
1952                 return -EINVAL;
1953
1954         do {
1955                 memset(cmd, 0, 16);
1956                 cmd[0] = SERVICE_ACTION_IN_16;
1957                 cmd[1] = SAI_READ_CAPACITY_16;
1958                 cmd[13] = RC16_LEN;
1959                 memset(buffer, 0, RC16_LEN);
1960
1961                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1962                                         buffer, RC16_LEN, &sshdr,
1963                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1964
1965                 if (media_not_present(sdkp, &sshdr))
1966                         return -ENODEV;
1967
1968                 if (the_result) {
1969                         sense_valid = scsi_sense_valid(&sshdr);
1970                         if (sense_valid &&
1971                             sshdr.sense_key == ILLEGAL_REQUEST &&
1972                             (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1973                             sshdr.ascq == 0x00)
1974                                 /* Invalid Command Operation Code or
1975                                  * Invalid Field in CDB, just retry
1976                                  * silently with RC10 */
1977                                 return -EINVAL;
1978                         if (sense_valid &&
1979                             sshdr.sense_key == UNIT_ATTENTION &&
1980                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1981                                 /* Device reset might occur several times,
1982                                  * give it one more chance */
1983                                 if (--reset_retries > 0)
1984                                         continue;
1985                 }
1986                 retries--;
1987
1988         } while (the_result && retries);
1989
1990         if (the_result) {
1991                 sd_print_result(sdkp, "Read Capacity(16) failed", the_result);
1992                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1993                 return -EINVAL;
1994         }
1995
1996         sector_size = get_unaligned_be32(&buffer[8]);
1997         lba = get_unaligned_be64(&buffer[0]);
1998
1999         if (sd_read_protection_type(sdkp, buffer) < 0) {
2000                 sdkp->capacity = 0;
2001                 return -ENODEV;
2002         }
2003
2004         if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
2005                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
2006                         "kernel compiled with support for large block "
2007                         "devices.\n");
2008                 sdkp->capacity = 0;
2009                 return -EOVERFLOW;
2010         }
2011
2012         /* Logical blocks per physical block exponent */
2013         sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
2014
2015         /* Lowest aligned logical block */
2016         alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
2017         blk_queue_alignment_offset(sdp->request_queue, alignment);
2018         if (alignment && sdkp->first_scan)
2019                 sd_printk(KERN_NOTICE, sdkp,
2020                           "physical block alignment offset: %u\n", alignment);
2021
2022         if (buffer[14] & 0x80) { /* LBPME */
2023                 sdkp->lbpme = 1;
2024
2025                 if (buffer[14] & 0x40) /* LBPRZ */
2026                         sdkp->lbprz = 1;
2027
2028                 sd_config_discard(sdkp, SD_LBP_WS16);
2029         }
2030
2031         sdkp->capacity = lba + 1;
2032         return sector_size;
2033 }
2034
2035 static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
2036                                                 unsigned char *buffer)
2037 {
2038         unsigned char cmd[16];
2039         struct scsi_sense_hdr sshdr;
2040         int sense_valid = 0;
2041         int the_result;
2042         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
2043         sector_t lba;
2044         unsigned sector_size;
2045
2046         do {
2047                 cmd[0] = READ_CAPACITY;
2048                 memset(&cmd[1], 0, 9);
2049                 memset(buffer, 0, 8);
2050
2051                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
2052                                         buffer, 8, &sshdr,
2053                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2054
2055                 if (media_not_present(sdkp, &sshdr))
2056                         return -ENODEV;
2057
2058                 if (the_result) {
2059                         sense_valid = scsi_sense_valid(&sshdr);
2060                         if (sense_valid &&
2061                             sshdr.sense_key == UNIT_ATTENTION &&
2062                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
2063                                 /* Device reset might occur several times,
2064                                  * give it one more chance */
2065                                 if (--reset_retries > 0)
2066                                         continue;
2067                 }
2068                 retries--;
2069
2070         } while (the_result && retries);
2071
2072         if (the_result) {
2073                 sd_print_result(sdkp, "Read Capacity(10) failed", the_result);
2074                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
2075                 return -EINVAL;
2076         }
2077
2078         sector_size = get_unaligned_be32(&buffer[4]);
2079         lba = get_unaligned_be32(&buffer[0]);
2080
2081         if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
2082                 /* Some buggy (usb cardreader) devices return an lba of
2083                    0xffffffff when the want to report a size of 0 (with
2084                    which they really mean no media is present) */
2085                 sdkp->capacity = 0;
2086                 sdkp->physical_block_size = sector_size;
2087                 return sector_size;
2088         }
2089
2090         if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
2091                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
2092                         "kernel compiled with support for large block "
2093                         "devices.\n");
2094                 sdkp->capacity = 0;
2095                 return -EOVERFLOW;
2096         }
2097
2098         sdkp->capacity = lba + 1;
2099         sdkp->physical_block_size = sector_size;
2100         return sector_size;
2101 }
2102
2103 static int sd_try_rc16_first(struct scsi_device *sdp)
2104 {
2105         if (sdp->host->max_cmd_len < 16)
2106                 return 0;
2107         if (sdp->try_rc_10_first)
2108                 return 0;
2109         if (sdp->scsi_level > SCSI_SPC_2)
2110                 return 1;
2111         if (scsi_device_protection(sdp))
2112                 return 1;
2113         return 0;
2114 }
2115
2116 /*
2117  * read disk capacity
2118  */
2119 static void
2120 sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
2121 {
2122         int sector_size;
2123         struct scsi_device *sdp = sdkp->device;
2124         sector_t old_capacity = sdkp->capacity;
2125
2126         if (sd_try_rc16_first(sdp)) {
2127                 sector_size = read_capacity_16(sdkp, sdp, buffer);
2128                 if (sector_size == -EOVERFLOW)
2129                         goto got_data;
2130                 if (sector_size == -ENODEV)
2131                         return;
2132                 if (sector_size < 0)
2133                         sector_size = read_capacity_10(sdkp, sdp, buffer);
2134                 if (sector_size < 0)
2135                         return;
2136         } else {
2137                 sector_size = read_capacity_10(sdkp, sdp, buffer);
2138                 if (sector_size == -EOVERFLOW)
2139                         goto got_data;
2140                 if (sector_size < 0)
2141                         return;
2142                 if ((sizeof(sdkp->capacity) > 4) &&
2143                     (sdkp->capacity > 0xffffffffULL)) {
2144                         int old_sector_size = sector_size;
2145                         sd_printk(KERN_NOTICE, sdkp, "Very big device. "
2146                                         "Trying to use READ CAPACITY(16).\n");
2147                         sector_size = read_capacity_16(sdkp, sdp, buffer);
2148                         if (sector_size < 0) {
2149                                 sd_printk(KERN_NOTICE, sdkp,
2150                                         "Using 0xffffffff as device size\n");
2151                                 sdkp->capacity = 1 + (sector_t) 0xffffffff;
2152                                 sector_size = old_sector_size;
2153                                 goto got_data;
2154                         }
2155                 }
2156         }
2157
2158         /* Some devices are known to return the total number of blocks,
2159          * not the highest block number.  Some devices have versions
2160          * which do this and others which do not.  Some devices we might
2161          * suspect of doing this but we don't know for certain.
2162          *
2163          * If we know the reported capacity is wrong, decrement it.  If
2164          * we can only guess, then assume the number of blocks is even
2165          * (usually true but not always) and err on the side of lowering
2166          * the capacity.
2167          */
2168         if (sdp->fix_capacity ||
2169             (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
2170                 sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
2171                                 "from its reported value: %llu\n",
2172                                 (unsigned long long) sdkp->capacity);
2173                 --sdkp->capacity;
2174         }
2175
2176 got_data:
2177         if (sector_size == 0) {
2178                 sector_size = 512;
2179                 sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
2180                           "assuming 512.\n");
2181         }
2182
2183         if (sector_size != 512 &&
2184             sector_size != 1024 &&
2185             sector_size != 2048 &&
2186             sector_size != 4096) {
2187                 sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
2188                           sector_size);
2189                 /*
2190                  * The user might want to re-format the drive with
2191                  * a supported sectorsize.  Once this happens, it
2192                  * would be relatively trivial to set the thing up.
2193                  * For this reason, we leave the thing in the table.
2194                  */
2195                 sdkp->capacity = 0;
2196                 /*
2197                  * set a bogus sector size so the normal read/write
2198                  * logic in the block layer will eventually refuse any
2199                  * request on this device without tripping over power
2200                  * of two sector size assumptions
2201                  */
2202                 sector_size = 512;
2203         }
2204         blk_queue_logical_block_size(sdp->request_queue, sector_size);
2205
2206         {
2207                 char cap_str_2[10], cap_str_10[10];
2208
2209                 string_get_size(sdkp->capacity, sector_size,
2210                                 STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
2211                 string_get_size(sdkp->capacity, sector_size,
2212                                 STRING_UNITS_10, cap_str_10,
2213                                 sizeof(cap_str_10));
2214
2215                 if (sdkp->first_scan || old_capacity != sdkp->capacity) {
2216                         sd_printk(KERN_NOTICE, sdkp,
2217                                   "%llu %d-byte logical blocks: (%s/%s)\n",
2218                                   (unsigned long long)sdkp->capacity,
2219                                   sector_size, cap_str_10, cap_str_2);
2220
2221                         if (sdkp->physical_block_size != sector_size)
2222                                 sd_printk(KERN_NOTICE, sdkp,
2223                                           "%u-byte physical blocks\n",
2224                                           sdkp->physical_block_size);
2225                 }
2226         }
2227
2228         if (sdkp->capacity > 0xffffffff) {
2229                 sdp->use_16_for_rw = 1;
2230                 sdkp->max_xfer_blocks = SD_MAX_XFER_BLOCKS;
2231         } else
2232                 sdkp->max_xfer_blocks = SD_DEF_XFER_BLOCKS;
2233
2234         /* Rescale capacity to 512-byte units */
2235         if (sector_size == 4096)
2236                 sdkp->capacity <<= 3;
2237         else if (sector_size == 2048)
2238                 sdkp->capacity <<= 2;
2239         else if (sector_size == 1024)
2240                 sdkp->capacity <<= 1;
2241
2242         blk_queue_physical_block_size(sdp->request_queue,
2243                                       sdkp->physical_block_size);
2244         sdkp->device->sector_size = sector_size;
2245 }
2246
2247 /* called with buffer of length 512 */
2248 static inline int
2249 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
2250                  unsigned char *buffer, int len, struct scsi_mode_data *data,
2251                  struct scsi_sense_hdr *sshdr)
2252 {
2253         return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
2254                                SD_TIMEOUT, SD_MAX_RETRIES, data,
2255                                sshdr);
2256 }
2257
2258 /*
2259  * read write protect setting, if possible - called only in sd_revalidate_disk()
2260  * called with buffer of length SD_BUF_SIZE
2261  */
2262 static void
2263 sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
2264 {
2265         int res;
2266         struct scsi_device *sdp = sdkp->device;
2267         struct scsi_mode_data data;
2268         int old_wp = sdkp->write_prot;
2269
2270         set_disk_ro(sdkp->disk, 0);
2271         if (sdp->skip_ms_page_3f) {
2272                 sd_first_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
2273                 return;
2274         }
2275
2276         if (sdp->use_192_bytes_for_3f) {
2277                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
2278         } else {
2279                 /*
2280                  * First attempt: ask for all pages (0x3F), but only 4 bytes.
2281                  * We have to start carefully: some devices hang if we ask
2282                  * for more than is available.
2283                  */
2284                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
2285
2286                 /*
2287                  * Second attempt: ask for page 0 When only page 0 is
2288                  * implemented, a request for page 3F may return Sense Key
2289                  * 5: Illegal Request, Sense Code 24: Invalid field in
2290                  * CDB.
2291                  */
2292                 if (!scsi_status_is_good(res))
2293                         res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
2294
2295                 /*
2296                  * Third attempt: ask 255 bytes, as we did earlier.
2297                  */
2298                 if (!scsi_status_is_good(res))
2299                         res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
2300                                                &data, NULL);
2301         }
2302
2303         if (!scsi_status_is_good(res)) {
2304                 sd_first_printk(KERN_WARNING, sdkp,
2305                           "Test WP failed, assume Write Enabled\n");
2306         } else {
2307                 sdkp->write_prot = ((data.device_specific & 0x80) != 0);
2308                 set_disk_ro(sdkp->disk, sdkp->write_prot);
2309                 if (sdkp->first_scan || old_wp != sdkp->write_prot) {
2310                         sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
2311                                   sdkp->write_prot ? "on" : "off");
2312                         sd_printk(KERN_DEBUG, sdkp,
2313                                   "Mode Sense: %02x %02x %02x %02x\n",
2314                                   buffer[0], buffer[1], buffer[2], buffer[3]);
2315                 }
2316         }
2317 }
2318
2319 /*
2320  * sd_read_cache_type - called only from sd_revalidate_disk()
2321  * called with buffer of length SD_BUF_SIZE
2322  */
2323 static void
2324 sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
2325 {
2326         int len = 0, res;
2327         struct scsi_device *sdp = sdkp->device;
2328
2329         int dbd;
2330         int modepage;
2331         int first_len;
2332         struct scsi_mode_data data;
2333         struct scsi_sense_hdr sshdr;
2334         int old_wce = sdkp->WCE;
2335         int old_rcd = sdkp->RCD;
2336         int old_dpofua = sdkp->DPOFUA;
2337
2338
2339         if (sdkp->cache_override)
2340                 return;
2341
2342         first_len = 4;
2343         if (sdp->skip_ms_page_8) {
2344                 if (sdp->type == TYPE_RBC)
2345                         goto defaults;
2346                 else {
2347                         if (sdp->skip_ms_page_3f)
2348                                 goto defaults;
2349                         modepage = 0x3F;
2350                         if (sdp->use_192_bytes_for_3f)
2351                                 first_len = 192;
2352                         dbd = 0;
2353                 }
2354         } else if (sdp->type == TYPE_RBC) {
2355                 modepage = 6;
2356                 dbd = 8;
2357         } else {
2358                 modepage = 8;
2359                 dbd = 0;
2360         }
2361
2362         /* cautiously ask */
2363         res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
2364                         &data, &sshdr);
2365
2366         if (!scsi_status_is_good(res))
2367                 goto bad_sense;
2368
2369         if (!data.header_length) {
2370                 modepage = 6;
2371                 first_len = 0;
2372                 sd_first_printk(KERN_ERR, sdkp,
2373                                 "Missing header in MODE_SENSE response\n");
2374         }
2375
2376         /* that went OK, now ask for the proper length */
2377         len = data.length;
2378
2379         /*
2380          * We're only interested in the first three bytes, actually.
2381          * But the data cache page is defined for the first 20.
2382          */
2383         if (len < 3)
2384                 goto bad_sense;
2385         else if (len > SD_BUF_SIZE) {
2386                 sd_first_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
2387                           "data from %d to %d bytes\n", len, SD_BUF_SIZE);
2388                 len = SD_BUF_SIZE;
2389         }
2390         if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
2391                 len = 192;
2392
2393         /* Get the data */
2394         if (len > first_len)
2395                 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
2396                                 &data, &sshdr);
2397
2398         if (scsi_status_is_good(res)) {
2399                 int offset = data.header_length + data.block_descriptor_length;
2400
2401                 while (offset < len) {
2402                         u8 page_code = buffer[offset] & 0x3F;
2403                         u8 spf       = buffer[offset] & 0x40;
2404
2405                         if (page_code == 8 || page_code == 6) {
2406                                 /* We're interested only in the first 3 bytes.
2407                                  */
2408                                 if (len - offset <= 2) {
2409                                         sd_first_printk(KERN_ERR, sdkp,
2410                                                 "Incomplete mode parameter "
2411                                                         "data\n");
2412                                         goto defaults;
2413                                 } else {
2414                                         modepage = page_code;
2415                                         goto Page_found;
2416                                 }
2417                         } else {
2418                                 /* Go to the next page */
2419                                 if (spf && len - offset > 3)
2420                                         offset += 4 + (buffer[offset+2] << 8) +
2421                                                 buffer[offset+3];
2422                                 else if (!spf && len - offset > 1)
2423                                         offset += 2 + buffer[offset+1];
2424                                 else {
2425                                         sd_first_printk(KERN_ERR, sdkp,
2426                                                         "Incomplete mode "
2427                                                         "parameter data\n");
2428                                         goto defaults;
2429                                 }
2430                         }
2431                 }
2432
2433                 sd_first_printk(KERN_ERR, sdkp, "No Caching mode page found\n");
2434                 goto defaults;
2435
2436         Page_found:
2437                 if (modepage == 8) {
2438                         sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
2439                         sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
2440                 } else {
2441                         sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
2442                         sdkp->RCD = 0;
2443                 }
2444
2445                 sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
2446                 if (sdp->broken_fua) {
2447                         sd_first_printk(KERN_NOTICE, sdkp, "Disabling FUA\n");
2448                         sdkp->DPOFUA = 0;
2449                 } else if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
2450                         sd_first_printk(KERN_NOTICE, sdkp,
2451                                   "Uses READ/WRITE(6), disabling FUA\n");
2452                         sdkp->DPOFUA = 0;
2453                 }
2454
2455                 /* No cache flush allowed for write protected devices */
2456                 if (sdkp->WCE && sdkp->write_prot)
2457                         sdkp->WCE = 0;
2458
2459                 if (sdkp->first_scan || old_wce != sdkp->WCE ||
2460                     old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
2461                         sd_printk(KERN_NOTICE, sdkp,
2462                                   "Write cache: %s, read cache: %s, %s\n",
2463                                   sdkp->WCE ? "enabled" : "disabled",
2464                                   sdkp->RCD ? "disabled" : "enabled",
2465                                   sdkp->DPOFUA ? "supports DPO and FUA"
2466                                   : "doesn't support DPO or FUA");
2467
2468                 return;
2469         }
2470
2471 bad_sense:
2472         if (scsi_sense_valid(&sshdr) &&
2473             sshdr.sense_key == ILLEGAL_REQUEST &&
2474             sshdr.asc == 0x24 && sshdr.ascq == 0x0)
2475                 /* Invalid field in CDB */
2476                 sd_first_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
2477         else
2478                 sd_first_printk(KERN_ERR, sdkp,
2479                                 "Asking for cache data failed\n");
2480
2481 defaults:
2482         if (sdp->wce_default_on) {
2483                 sd_first_printk(KERN_NOTICE, sdkp,
2484                                 "Assuming drive cache: write back\n");
2485                 sdkp->WCE = 1;
2486         } else {
2487                 sd_first_printk(KERN_ERR, sdkp,
2488                                 "Assuming drive cache: write through\n");
2489                 sdkp->WCE = 0;
2490         }
2491         sdkp->RCD = 0;
2492         sdkp->DPOFUA = 0;
2493 }
2494
2495 /*
2496  * The ATO bit indicates whether the DIF application tag is available
2497  * for use by the operating system.
2498  */
2499 static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
2500 {
2501         int res, offset;
2502         struct scsi_device *sdp = sdkp->device;
2503         struct scsi_mode_data data;
2504         struct scsi_sense_hdr sshdr;
2505
2506         if (sdp->type != TYPE_DISK)
2507                 return;
2508
2509         if (sdkp->protection_type == 0)
2510                 return;
2511
2512         res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
2513                               SD_MAX_RETRIES, &data, &sshdr);
2514
2515         if (!scsi_status_is_good(res) || !data.header_length ||
2516             data.length < 6) {
2517                 sd_first_printk(KERN_WARNING, sdkp,
2518                           "getting Control mode page failed, assume no ATO\n");
2519
2520                 if (scsi_sense_valid(&sshdr))
2521                         sd_print_sense_hdr(sdkp, &sshdr);
2522
2523                 return;
2524         }
2525
2526         offset = data.header_length + data.block_descriptor_length;
2527
2528         if ((buffer[offset] & 0x3f) != 0x0a) {
2529                 sd_first_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
2530                 return;
2531         }
2532
2533         if ((buffer[offset + 5] & 0x80) == 0)
2534                 return;
2535
2536         sdkp->ATO = 1;
2537
2538         return;
2539 }
2540
2541 /**
2542  * sd_read_block_limits - Query disk device for preferred I/O sizes.
2543  * @disk: disk to query
2544  */
2545 static void sd_read_block_limits(struct scsi_disk *sdkp)
2546 {
2547         unsigned int sector_sz = sdkp->device->sector_size;
2548         const int vpd_len = 64;
2549         u32 max_xfer_length;
2550         unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
2551
2552         if (!buffer ||
2553             /* Block Limits VPD */
2554             scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
2555                 goto out;
2556
2557         max_xfer_length = get_unaligned_be32(&buffer[8]);
2558         if (max_xfer_length)
2559                 sdkp->max_xfer_blocks = max_xfer_length;
2560
2561         blk_queue_io_min(sdkp->disk->queue,
2562                          get_unaligned_be16(&buffer[6]) * sector_sz);
2563         blk_queue_io_opt(sdkp->disk->queue,
2564                          get_unaligned_be32(&buffer[12]) * sector_sz);
2565
2566         if (buffer[3] == 0x3c) {
2567                 unsigned int lba_count, desc_count;
2568
2569                 sdkp->max_ws_blocks = (u32)get_unaligned_be64(&buffer[36]);
2570
2571                 if (!sdkp->lbpme)
2572                         goto out;
2573
2574                 lba_count = get_unaligned_be32(&buffer[20]);
2575                 desc_count = get_unaligned_be32(&buffer[24]);
2576
2577                 if (lba_count && desc_count)
2578                         sdkp->max_unmap_blocks = lba_count;
2579
2580                 sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
2581
2582                 if (buffer[32] & 0x80)
2583                         sdkp->unmap_alignment =
2584                                 get_unaligned_be32(&buffer[32]) & ~(1 << 31);
2585
2586                 if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
2587
2588                         if (sdkp->max_unmap_blocks)
2589                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2590                         else
2591                                 sd_config_discard(sdkp, SD_LBP_WS16);
2592
2593                 } else {        /* LBP VPD page tells us what to use */
2594                         if (sdkp->lbpu && sdkp->max_unmap_blocks && !sdkp->lbprz)
2595                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2596                         else if (sdkp->lbpws)
2597                                 sd_config_discard(sdkp, SD_LBP_WS16);
2598                         else if (sdkp->lbpws10)
2599                                 sd_config_discard(sdkp, SD_LBP_WS10);
2600                         else if (sdkp->lbpu && sdkp->max_unmap_blocks)
2601                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2602                         else
2603                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
2604                 }
2605         }
2606
2607  out:
2608         kfree(buffer);
2609 }
2610
2611 /**
2612  * sd_read_block_characteristics - Query block dev. characteristics
2613  * @disk: disk to query
2614  */
2615 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
2616 {
2617         unsigned char *buffer;
2618         u16 rot;
2619         const int vpd_len = 64;
2620
2621         buffer = kmalloc(vpd_len, GFP_KERNEL);
2622
2623         if (!buffer ||
2624             /* Block Device Characteristics VPD */
2625             scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
2626                 goto out;
2627
2628         rot = get_unaligned_be16(&buffer[4]);
2629
2630         if (rot == 1) {
2631                 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
2632                 queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, sdkp->disk->queue);
2633         }
2634
2635  out:
2636         kfree(buffer);
2637 }
2638
2639 /**
2640  * sd_read_block_provisioning - Query provisioning VPD page
2641  * @disk: disk to query
2642  */
2643 static void sd_read_block_provisioning(struct scsi_disk *sdkp)
2644 {
2645         unsigned char *buffer;
2646         const int vpd_len = 8;
2647
2648         if (sdkp->lbpme == 0)
2649                 return;
2650
2651         buffer = kmalloc(vpd_len, GFP_KERNEL);
2652
2653         if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
2654                 goto out;
2655
2656         sdkp->lbpvpd    = 1;
2657         sdkp->lbpu      = (buffer[5] >> 7) & 1; /* UNMAP */
2658         sdkp->lbpws     = (buffer[5] >> 6) & 1; /* WRITE SAME(16) with UNMAP */
2659         sdkp->lbpws10   = (buffer[5] >> 5) & 1; /* WRITE SAME(10) with UNMAP */
2660
2661  out:
2662         kfree(buffer);
2663 }
2664
2665 static void sd_read_write_same(struct scsi_disk *sdkp, unsigned char *buffer)
2666 {
2667         struct scsi_device *sdev = sdkp->device;
2668
2669         if (sdev->host->no_write_same) {
2670                 sdev->no_write_same = 1;
2671
2672                 return;
2673         }
2674
2675         if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, INQUIRY) < 0) {
2676                 /* too large values might cause issues with arcmsr */
2677                 int vpd_buf_len = 64;
2678
2679                 sdev->no_report_opcodes = 1;
2680
2681                 /* Disable WRITE SAME if REPORT SUPPORTED OPERATION
2682                  * CODES is unsupported and the device has an ATA
2683                  * Information VPD page (SAT).
2684                  */
2685                 if (!scsi_get_vpd_page(sdev, 0x89, buffer, vpd_buf_len))
2686                         sdev->no_write_same = 1;
2687         }
2688
2689         if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME_16) == 1)
2690                 sdkp->ws16 = 1;
2691
2692         if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME) == 1)
2693                 sdkp->ws10 = 1;
2694 }
2695
2696 static int sd_try_extended_inquiry(struct scsi_device *sdp)
2697 {
2698         /* Attempt VPD inquiry if the device blacklist explicitly calls
2699          * for it.
2700          */
2701         if (sdp->try_vpd_pages)
2702                 return 1;
2703         /*
2704          * Although VPD inquiries can go to SCSI-2 type devices,
2705          * some USB ones crash on receiving them, and the pages
2706          * we currently ask for are for SPC-3 and beyond
2707          */
2708         if (sdp->scsi_level > SCSI_SPC_2 && !sdp->skip_vpd_pages)
2709                 return 1;
2710         return 0;
2711 }
2712
2713 /**
2714  *      sd_revalidate_disk - called the first time a new disk is seen,
2715  *      performs disk spin up, read_capacity, etc.
2716  *      @disk: struct gendisk we care about
2717  **/
2718 static int sd_revalidate_disk(struct gendisk *disk)
2719 {
2720         struct scsi_disk *sdkp = scsi_disk(disk);
2721         struct scsi_device *sdp = sdkp->device;
2722         unsigned char *buffer;
2723         unsigned int max_xfer;
2724
2725         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
2726                                       "sd_revalidate_disk\n"));
2727
2728         /*
2729          * If the device is offline, don't try and read capacity or any
2730          * of the other niceties.
2731          */
2732         if (!scsi_device_online(sdp))
2733                 goto out;
2734
2735         buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
2736         if (!buffer) {
2737                 sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
2738                           "allocation failure.\n");
2739                 goto out;
2740         }
2741
2742         sd_spinup_disk(sdkp);
2743
2744         /*
2745          * Without media there is no reason to ask; moreover, some devices
2746          * react badly if we do.
2747          */
2748         if (sdkp->media_present) {
2749                 sd_read_capacity(sdkp, buffer);
2750
2751                 if (sd_try_extended_inquiry(sdp)) {
2752                         sd_read_block_provisioning(sdkp);
2753                         sd_read_block_limits(sdkp);
2754                         sd_read_block_characteristics(sdkp);
2755                 }
2756
2757                 sd_read_write_protect_flag(sdkp, buffer);
2758                 sd_read_cache_type(sdkp, buffer);
2759                 sd_read_app_tag_own(sdkp, buffer);
2760                 sd_read_write_same(sdkp, buffer);
2761         }
2762
2763         sdkp->first_scan = 0;
2764
2765         /*
2766          * We now have all cache related info, determine how we deal
2767          * with flush requests.
2768          */
2769         sd_set_flush_flag(sdkp);
2770
2771         max_xfer = sdkp->max_xfer_blocks;
2772         max_xfer <<= ilog2(sdp->sector_size) - 9;
2773
2774         sdkp->disk->queue->limits.max_sectors =
2775                 min_not_zero(queue_max_hw_sectors(sdkp->disk->queue), max_xfer);
2776
2777         set_capacity(disk, sdkp->capacity);
2778         sd_config_write_same(sdkp);
2779         kfree(buffer);
2780
2781  out:
2782         return 0;
2783 }
2784
2785 /**
2786  *      sd_unlock_native_capacity - unlock native capacity
2787  *      @disk: struct gendisk to set capacity for
2788  *
2789  *      Block layer calls this function if it detects that partitions
2790  *      on @disk reach beyond the end of the device.  If the SCSI host
2791  *      implements ->unlock_native_capacity() method, it's invoked to
2792  *      give it a chance to adjust the device capacity.
2793  *
2794  *      CONTEXT:
2795  *      Defined by block layer.  Might sleep.
2796  */
2797 static void sd_unlock_native_capacity(struct gendisk *disk)
2798 {
2799         struct scsi_device *sdev = scsi_disk(disk)->device;
2800
2801         if (sdev->host->hostt->unlock_native_capacity)
2802                 sdev->host->hostt->unlock_native_capacity(sdev);
2803 }
2804
2805 /**
2806  *      sd_format_disk_name - format disk name
2807  *      @prefix: name prefix - ie. "sd" for SCSI disks
2808  *      @index: index of the disk to format name for
2809  *      @buf: output buffer
2810  *      @buflen: length of the output buffer
2811  *
2812  *      SCSI disk names starts at sda.  The 26th device is sdz and the
2813  *      27th is sdaa.  The last one for two lettered suffix is sdzz
2814  *      which is followed by sdaaa.
2815  *
2816  *      This is basically 26 base counting with one extra 'nil' entry
2817  *      at the beginning from the second digit on and can be
2818  *      determined using similar method as 26 base conversion with the
2819  *      index shifted -1 after each digit is computed.
2820  *
2821  *      CONTEXT:
2822  *      Don't care.
2823  *
2824  *      RETURNS:
2825  *      0 on success, -errno on failure.
2826  */
2827 static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
2828 {
2829         const int base = 'z' - 'a' + 1;
2830         char *begin = buf + strlen(prefix);
2831         char *end = buf + buflen;
2832         char *p;
2833         int unit;
2834
2835         p = end - 1;
2836         *p = '\0';
2837         unit = base;
2838         do {
2839                 if (p == begin)
2840                         return -EINVAL;
2841                 *--p = 'a' + (index % unit);
2842                 index = (index / unit) - 1;
2843         } while (index >= 0);
2844
2845         memmove(begin, p, end - p);
2846         memcpy(buf, prefix, strlen(prefix));
2847
2848         return 0;
2849 }
2850
2851 /*
2852  * The asynchronous part of sd_probe
2853  */
2854 static void sd_probe_async(void *data, async_cookie_t cookie)
2855 {
2856         struct scsi_disk *sdkp = data;
2857         struct scsi_device *sdp;
2858         struct gendisk *gd;
2859         u32 index;
2860         struct device *dev;
2861
2862         sdp = sdkp->device;
2863         gd = sdkp->disk;
2864         index = sdkp->index;
2865         dev = &sdp->sdev_gendev;
2866
2867         gd->major = sd_major((index & 0xf0) >> 4);
2868         gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
2869         gd->minors = SD_MINORS;
2870
2871         gd->fops = &sd_fops;
2872         gd->private_data = &sdkp->driver;
2873         gd->queue = sdkp->device->request_queue;
2874
2875         /* defaults, until the device tells us otherwise */
2876         sdp->sector_size = 512;
2877         sdkp->capacity = 0;
2878         sdkp->media_present = 1;
2879         sdkp->write_prot = 0;
2880         sdkp->cache_override = 0;
2881         sdkp->WCE = 0;
2882         sdkp->RCD = 0;
2883         sdkp->ATO = 0;
2884         sdkp->first_scan = 1;
2885         sdkp->max_medium_access_timeouts = SD_MAX_MEDIUM_TIMEOUTS;
2886
2887         sd_revalidate_disk(gd);
2888
2889         gd->driverfs_dev = &sdp->sdev_gendev;
2890         gd->flags = GENHD_FL_EXT_DEVT;
2891         if (sdp->removable) {
2892                 gd->flags |= GENHD_FL_REMOVABLE;
2893                 gd->events |= DISK_EVENT_MEDIA_CHANGE;
2894         }
2895
2896         blk_pm_runtime_init(sdp->request_queue, dev);
2897         add_disk(gd);
2898         if (sdkp->capacity)
2899                 sd_dif_config_host(sdkp);
2900
2901         sd_revalidate_disk(gd);
2902
2903         sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
2904                   sdp->removable ? "removable " : "");
2905         scsi_autopm_put_device(sdp);
2906         put_device(&sdkp->dev);
2907 }
2908
2909 /**
2910  *      sd_probe - called during driver initialization and whenever a
2911  *      new scsi device is attached to the system. It is called once
2912  *      for each scsi device (not just disks) present.
2913  *      @dev: pointer to device object
2914  *
2915  *      Returns 0 if successful (or not interested in this scsi device
2916  *      (e.g. scanner)); 1 when there is an error.
2917  *
2918  *      Note: this function is invoked from the scsi mid-level.
2919  *      This function sets up the mapping between a given
2920  *      <host,channel,id,lun> (found in sdp) and new device name
2921  *      (e.g. /dev/sda). More precisely it is the block device major
2922  *      and minor number that is chosen here.
2923  *
2924  *      Assume sd_probe is not re-entrant (for time being)
2925  *      Also think about sd_probe() and sd_remove() running coincidentally.
2926  **/
2927 static int sd_probe(struct device *dev)
2928 {
2929         struct scsi_device *sdp = to_scsi_device(dev);
2930         struct scsi_disk *sdkp;
2931         struct gendisk *gd;
2932         int index;
2933         int error;
2934
2935         scsi_autopm_get_device(sdp);
2936         error = -ENODEV;
2937         if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
2938                 goto out;
2939
2940         SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
2941                                         "sd_probe\n"));
2942
2943         error = -ENOMEM;
2944         sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
2945         if (!sdkp)
2946                 goto out;
2947
2948         gd = alloc_disk(SD_MINORS);
2949         if (!gd)
2950                 goto out_free;
2951
2952         do {
2953                 if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
2954                         goto out_put;
2955
2956                 spin_lock(&sd_index_lock);
2957                 error = ida_get_new(&sd_index_ida, &index);
2958                 spin_unlock(&sd_index_lock);
2959         } while (error == -EAGAIN);
2960
2961         if (error) {
2962                 sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
2963                 goto out_put;
2964         }
2965
2966         error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
2967         if (error) {
2968                 sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name length exceeded.\n");
2969                 goto out_free_index;
2970         }
2971
2972         sdkp->device = sdp;
2973         sdkp->driver = &sd_template;
2974         sdkp->disk = gd;
2975         sdkp->index = index;
2976         atomic_set(&sdkp->openers, 0);
2977         atomic_set(&sdkp->device->ioerr_cnt, 0);
2978
2979         if (!sdp->request_queue->rq_timeout) {
2980                 if (sdp->type != TYPE_MOD)
2981                         blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
2982                 else
2983                         blk_queue_rq_timeout(sdp->request_queue,
2984                                              SD_MOD_TIMEOUT);
2985         }
2986
2987         device_initialize(&sdkp->dev);
2988         sdkp->dev.parent = dev;
2989         sdkp->dev.class = &sd_disk_class;
2990         dev_set_name(&sdkp->dev, "%s", dev_name(dev));
2991
2992         error = device_add(&sdkp->dev);
2993         if (error)
2994                 goto out_free_index;
2995
2996         get_device(dev);
2997         dev_set_drvdata(dev, sdkp);
2998
2999         get_device(&sdkp->dev); /* prevent release before async_schedule */
3000         async_schedule_domain(sd_probe_async, sdkp, &scsi_sd_probe_domain);
3001
3002         return 0;
3003
3004  out_free_index:
3005         spin_lock(&sd_index_lock);
3006         ida_remove(&sd_index_ida, index);
3007         spin_unlock(&sd_index_lock);
3008  out_put:
3009         put_disk(gd);
3010  out_free:
3011         kfree(sdkp);
3012  out:
3013         scsi_autopm_put_device(sdp);
3014         return error;
3015 }
3016
3017 /**
3018  *      sd_remove - called whenever a scsi disk (previously recognized by
3019  *      sd_probe) is detached from the system. It is called (potentially
3020  *      multiple times) during sd module unload.
3021  *      @sdp: pointer to mid level scsi device object
3022  *
3023  *      Note: this function is invoked from the scsi mid-level.
3024  *      This function potentially frees up a device name (e.g. /dev/sdc)
3025  *      that could be re-used by a subsequent sd_probe().
3026  *      This function is not called when the built-in sd driver is "exit-ed".
3027  **/
3028 static int sd_remove(struct device *dev)
3029 {
3030         struct scsi_disk *sdkp;
3031         dev_t devt;
3032
3033         sdkp = dev_get_drvdata(dev);
3034         devt = disk_devt(sdkp->disk);
3035         scsi_autopm_get_device(sdkp->device);
3036
3037         async_synchronize_full_domain(&scsi_sd_pm_domain);
3038         async_synchronize_full_domain(&scsi_sd_probe_domain);
3039         device_del(&sdkp->dev);
3040         del_gendisk(sdkp->disk);
3041         sd_shutdown(dev);
3042
3043         blk_register_region(devt, SD_MINORS, NULL,
3044                             sd_default_probe, NULL, NULL);
3045
3046         mutex_lock(&sd_ref_mutex);
3047         dev_set_drvdata(dev, NULL);
3048         put_device(&sdkp->dev);
3049         mutex_unlock(&sd_ref_mutex);
3050
3051         return 0;
3052 }
3053
3054 /**
3055  *      scsi_disk_release - Called to free the scsi_disk structure
3056  *      @dev: pointer to embedded class device
3057  *
3058  *      sd_ref_mutex must be held entering this routine.  Because it is
3059  *      called on last put, you should always use the scsi_disk_get()
3060  *      scsi_disk_put() helpers which manipulate the semaphore directly
3061  *      and never do a direct put_device.
3062  **/
3063 static void scsi_disk_release(struct device *dev)
3064 {
3065         struct scsi_disk *sdkp = to_scsi_disk(dev);
3066         struct gendisk *disk = sdkp->disk;
3067
3068         spin_lock(&sd_index_lock);
3069         ida_remove(&sd_index_ida, sdkp->index);
3070         spin_unlock(&sd_index_lock);
3071
3072         blk_integrity_unregister(disk);
3073         disk->private_data = NULL;
3074         put_disk(disk);
3075         put_device(&sdkp->device->sdev_gendev);
3076
3077         kfree(sdkp);
3078 }
3079
3080 static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
3081 {
3082         unsigned char cmd[6] = { START_STOP };  /* START_VALID */
3083         struct scsi_sense_hdr sshdr;
3084         struct scsi_device *sdp = sdkp->device;
3085         int res;
3086
3087         if (start)
3088                 cmd[4] |= 1;    /* START */
3089
3090         if (sdp->start_stop_pwr_cond)
3091                 cmd[4] |= start ? 1 << 4 : 3 << 4;      /* Active or Standby */
3092
3093         if (!scsi_device_online(sdp))
3094                 return -ENODEV;
3095
3096         res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
3097                                SD_TIMEOUT, SD_MAX_RETRIES, NULL, REQ_PM);
3098         if (res) {
3099                 sd_print_result(sdkp, "Start/Stop Unit failed", res);
3100                 if (driver_byte(res) & DRIVER_SENSE)
3101                         sd_print_sense_hdr(sdkp, &sshdr);
3102                 if (scsi_sense_valid(&sshdr) &&
3103                         /* 0x3a is medium not present */
3104                         sshdr.asc == 0x3a)
3105                         res = 0;
3106         }
3107
3108         /* SCSI error codes must not go to the generic layer */
3109         if (res)
3110                 return -EIO;
3111
3112         return 0;
3113 }
3114
3115 /*
3116  * Send a SYNCHRONIZE CACHE instruction down to the device through
3117  * the normal SCSI command structure.  Wait for the command to
3118  * complete.
3119  */
3120 static void sd_shutdown(struct device *dev)
3121 {
3122         struct scsi_disk *sdkp = dev_get_drvdata(dev);
3123
3124         if (!sdkp)
3125                 return;         /* this can happen */
3126
3127         if (pm_runtime_suspended(dev))
3128                 return;
3129
3130         if (sdkp->WCE && sdkp->media_present) {
3131                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
3132                 sd_sync_cache(sdkp);
3133         }
3134
3135         if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
3136                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
3137                 sd_start_stop_device(sdkp, 0);
3138         }
3139 }
3140
3141 static int sd_suspend_common(struct device *dev, bool ignore_stop_errors)
3142 {
3143         struct scsi_disk *sdkp = dev_get_drvdata(dev);
3144         int ret = 0;
3145
3146         if (!sdkp)
3147                 return 0;       /* this can happen */
3148
3149         if (sdkp->WCE && sdkp->media_present) {
3150                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
3151                 ret = sd_sync_cache(sdkp);
3152                 if (ret) {
3153                         /* ignore OFFLINE device */
3154                         if (ret == -ENODEV)
3155                                 ret = 0;
3156                         goto done;
3157                 }
3158         }
3159
3160         if (sdkp->device->manage_start_stop) {
3161                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
3162                 /* an error is not worth aborting a system sleep */
3163                 ret = sd_start_stop_device(sdkp, 0);
3164                 if (ignore_stop_errors)
3165                         ret = 0;
3166         }
3167
3168 done:
3169         return ret;
3170 }
3171
3172 static int sd_suspend_system(struct device *dev)
3173 {
3174         return sd_suspend_common(dev, true);
3175 }
3176
3177 static int sd_suspend_runtime(struct device *dev)
3178 {
3179         return sd_suspend_common(dev, false);
3180 }
3181
3182 static int sd_resume(struct device *dev)
3183 {
3184         struct scsi_disk *sdkp = dev_get_drvdata(dev);
3185
3186         if (!sdkp->device->manage_start_stop)
3187                 return 0;
3188
3189         sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
3190         return sd_start_stop_device(sdkp, 1);
3191 }
3192
3193 /**
3194  *      init_sd - entry point for this driver (both when built in or when
3195  *      a module).
3196  *
3197  *      Note: this function registers this driver with the scsi mid-level.
3198  **/
3199 static int __init init_sd(void)
3200 {
3201         int majors = 0, i, err;
3202
3203         SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
3204
3205         for (i = 0; i < SD_MAJORS; i++) {
3206                 if (register_blkdev(sd_major(i), "sd") != 0)
3207                         continue;
3208                 majors++;
3209                 blk_register_region(sd_major(i), SD_MINORS, NULL,
3210                                     sd_default_probe, NULL, NULL);
3211         }
3212
3213         if (!majors)
3214                 return -ENODEV;
3215
3216         err = class_register(&sd_disk_class);
3217         if (err)
3218                 goto err_out;
3219
3220         sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
3221                                          0, 0, NULL);
3222         if (!sd_cdb_cache) {
3223                 printk(KERN_ERR "sd: can't init extended cdb cache\n");
3224                 err = -ENOMEM;
3225                 goto err_out_class;
3226         }
3227
3228         sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
3229         if (!sd_cdb_pool) {
3230                 printk(KERN_ERR "sd: can't init extended cdb pool\n");
3231                 err = -ENOMEM;
3232                 goto err_out_cache;
3233         }
3234
3235         err = scsi_register_driver(&sd_template.gendrv);
3236         if (err)
3237                 goto err_out_driver;
3238
3239         return 0;
3240
3241 err_out_driver:
3242         mempool_destroy(sd_cdb_pool);
3243
3244 err_out_cache:
3245         kmem_cache_destroy(sd_cdb_cache);
3246
3247 err_out_class:
3248         class_unregister(&sd_disk_class);
3249 err_out:
3250         for (i = 0; i < SD_MAJORS; i++)
3251                 unregister_blkdev(sd_major(i), "sd");
3252         return err;
3253 }
3254
3255 /**
3256  *      exit_sd - exit point for this driver (when it is a module).
3257  *
3258  *      Note: this function unregisters this driver from the scsi mid-level.
3259  **/
3260 static void __exit exit_sd(void)
3261 {
3262         int i;
3263
3264         SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
3265
3266         scsi_unregister_driver(&sd_template.gendrv);
3267         mempool_destroy(sd_cdb_pool);
3268         kmem_cache_destroy(sd_cdb_cache);
3269
3270         class_unregister(&sd_disk_class);
3271
3272         for (i = 0; i < SD_MAJORS; i++) {
3273                 blk_unregister_region(sd_major(i), SD_MINORS);
3274                 unregister_blkdev(sd_major(i), "sd");
3275         }
3276 }
3277
3278 module_init(init_sd);
3279 module_exit(exit_sd);
3280
3281 static void sd_print_sense_hdr(struct scsi_disk *sdkp,
3282                                struct scsi_sense_hdr *sshdr)
3283 {
3284         scsi_print_sense_hdr(sdkp->device,
3285                              sdkp->disk ? sdkp->disk->disk_name : NULL, sshdr);
3286 }
3287
3288 static void sd_print_result(const struct scsi_disk *sdkp, const char *msg,
3289                             int result)
3290 {
3291         const char *hb_string = scsi_hostbyte_string(result);
3292         const char *db_string = scsi_driverbyte_string(result);
3293
3294         if (hb_string || db_string)
3295                 sd_printk(KERN_INFO, sdkp,
3296                           "%s: Result: hostbyte=%s driverbyte=%s\n", msg,
3297                           hb_string ? hb_string : "invalid",
3298                           db_string ? db_string : "invalid");
3299         else
3300                 sd_printk(KERN_INFO, sdkp,
3301                           "%s: Result: hostbyte=0x%02x driverbyte=0x%02x\n",
3302                           msg, host_byte(result), driver_byte(result));
3303 }
3304