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