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 int 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         return 0;
1211 }
1212
1213 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1214 {
1215         struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
1216         struct scsi_device *sdp = sdkp->device;
1217         struct Scsi_Host *host = sdp->host;
1218         int diskinfo[4];
1219
1220         /* default to most commonly used values */
1221         diskinfo[0] = 0x40;     /* 1 << 6 */
1222         diskinfo[1] = 0x20;     /* 1 << 5 */
1223         diskinfo[2] = sdkp->capacity >> 11;
1224
1225         /* override with calculated, extended default, or driver values */
1226         if (host->hostt->bios_param)
1227                 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
1228         else
1229                 scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
1230
1231         geo->heads = diskinfo[0];
1232         geo->sectors = diskinfo[1];
1233         geo->cylinders = diskinfo[2];
1234         return 0;
1235 }
1236
1237 /**
1238  *      sd_ioctl - process an ioctl
1239  *      @inode: only i_rdev/i_bdev members may be used
1240  *      @filp: only f_mode and f_flags may be used
1241  *      @cmd: ioctl command number
1242  *      @arg: this is third argument given to ioctl(2) system call.
1243  *      Often contains a pointer.
1244  *
1245  *      Returns 0 if successful (some ioctls return positive numbers on
1246  *      success as well). Returns a negated errno value in case of error.
1247  *
1248  *      Note: most ioctls are forward onto the block subsystem or further
1249  *      down in the scsi subsystem.
1250  **/
1251 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
1252                     unsigned int cmd, unsigned long arg)
1253 {
1254         struct gendisk *disk = bdev->bd_disk;
1255         struct scsi_disk *sdkp = scsi_disk(disk);
1256         struct scsi_device *sdp = sdkp->device;
1257         void __user *p = (void __user *)arg;
1258         int error;
1259
1260         SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
1261                                     "cmd=0x%x\n", disk->disk_name, cmd));
1262
1263         error = scsi_verify_blk_ioctl(bdev, cmd);
1264         if (error < 0)
1265                 return error;
1266
1267         /*
1268          * If we are in the middle of error recovery, don't let anyone
1269          * else try and use this device.  Also, if error recovery fails, it
1270          * may try and take the device offline, in which case all further
1271          * access to the device is prohibited.
1272          */
1273         error = scsi_nonblockable_ioctl(sdp, cmd, p,
1274                                         (mode & FMODE_NDELAY) != 0);
1275         if (!scsi_block_when_processing_errors(sdp) || !error)
1276                 goto out;
1277
1278         /*
1279          * Send SCSI addressing ioctls directly to mid level, send other
1280          * ioctls to block level and then onto mid level if they can't be
1281          * resolved.
1282          */
1283         switch (cmd) {
1284                 case SCSI_IOCTL_GET_IDLUN:
1285                 case SCSI_IOCTL_GET_BUS_NUMBER:
1286                         error = scsi_ioctl(sdp, cmd, p);
1287                         break;
1288                 default:
1289                         error = scsi_cmd_blk_ioctl(bdev, mode, cmd, p);
1290                         if (error != -ENOTTY)
1291                                 break;
1292                         error = scsi_ioctl(sdp, cmd, p);
1293                         break;
1294         }
1295 out:
1296         return error;
1297 }
1298
1299 static void set_media_not_present(struct scsi_disk *sdkp)
1300 {
1301         if (sdkp->media_present)
1302                 sdkp->device->changed = 1;
1303
1304         if (sdkp->device->removable) {
1305                 sdkp->media_present = 0;
1306                 sdkp->capacity = 0;
1307         }
1308 }
1309
1310 static int media_not_present(struct scsi_disk *sdkp,
1311                              struct scsi_sense_hdr *sshdr)
1312 {
1313         if (!scsi_sense_valid(sshdr))
1314                 return 0;
1315
1316         /* not invoked for commands that could return deferred errors */
1317         switch (sshdr->sense_key) {
1318         case UNIT_ATTENTION:
1319         case NOT_READY:
1320                 /* medium not present */
1321                 if (sshdr->asc == 0x3A) {
1322                         set_media_not_present(sdkp);
1323                         return 1;
1324                 }
1325         }
1326         return 0;
1327 }
1328
1329 /**
1330  *      sd_check_events - check media events
1331  *      @disk: kernel device descriptor
1332  *      @clearing: disk events currently being cleared
1333  *
1334  *      Returns mask of DISK_EVENT_*.
1335  *
1336  *      Note: this function is invoked from the block subsystem.
1337  **/
1338 static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
1339 {
1340         struct scsi_disk *sdkp = scsi_disk(disk);
1341         struct scsi_device *sdp = sdkp->device;
1342         struct scsi_sense_hdr *sshdr = NULL;
1343         int retval;
1344
1345         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
1346
1347         /*
1348          * If the device is offline, don't send any commands - just pretend as
1349          * if the command failed.  If the device ever comes back online, we
1350          * can deal with it then.  It is only because of unrecoverable errors
1351          * that we would ever take a device offline in the first place.
1352          */
1353         if (!scsi_device_online(sdp)) {
1354                 set_media_not_present(sdkp);
1355                 goto out;
1356         }
1357
1358         /*
1359          * Using TEST_UNIT_READY enables differentiation between drive with
1360          * no cartridge loaded - NOT READY, drive with changed cartridge -
1361          * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
1362          *
1363          * Drives that auto spin down. eg iomega jaz 1G, will be started
1364          * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
1365          * sd_revalidate() is called.
1366          */
1367         retval = -ENODEV;
1368
1369         if (scsi_block_when_processing_errors(sdp)) {
1370                 retval = scsi_autopm_get_device(sdp);
1371                 if (retval)
1372                         goto out;
1373
1374                 sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
1375                 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
1376                                               sshdr);
1377                 scsi_autopm_put_device(sdp);
1378         }
1379
1380         /* failed to execute TUR, assume media not present */
1381         if (host_byte(retval)) {
1382                 set_media_not_present(sdkp);
1383                 goto out;
1384         }
1385
1386         if (media_not_present(sdkp, sshdr))
1387                 goto out;
1388
1389         /*
1390          * For removable scsi disk we have to recognise the presence
1391          * of a disk in the drive.
1392          */
1393         if (!sdkp->media_present)
1394                 sdp->changed = 1;
1395         sdkp->media_present = 1;
1396 out:
1397         /*
1398          * sdp->changed is set under the following conditions:
1399          *
1400          *      Medium present state has changed in either direction.
1401          *      Device has indicated UNIT_ATTENTION.
1402          */
1403         kfree(sshdr);
1404         retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
1405         sdp->changed = 0;
1406         return retval;
1407 }
1408
1409 static int sd_sync_cache(struct scsi_disk *sdkp)
1410 {
1411         int retries, res;
1412         struct scsi_device *sdp = sdkp->device;
1413         struct scsi_sense_hdr sshdr;
1414
1415         if (!scsi_device_online(sdp))
1416                 return -ENODEV;
1417
1418
1419         for (retries = 3; retries > 0; --retries) {
1420                 unsigned char cmd[10] = { 0 };
1421
1422                 cmd[0] = SYNCHRONIZE_CACHE;
1423                 /*
1424                  * Leave the rest of the command zero to indicate
1425                  * flush everything.
1426                  */
1427                 res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
1428                                        SD_FLUSH_TIMEOUT, SD_MAX_RETRIES, NULL);
1429                 if (res == 0)
1430                         break;
1431         }
1432
1433         if (res) {
1434                 sd_print_result(sdkp, res);
1435                 if (driver_byte(res) & DRIVER_SENSE)
1436                         sd_print_sense_hdr(sdkp, &sshdr);
1437         }
1438
1439         if (res)
1440                 return -EIO;
1441         return 0;
1442 }
1443
1444 static void sd_rescan(struct device *dev)
1445 {
1446         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
1447
1448         if (sdkp) {
1449                 revalidate_disk(sdkp->disk);
1450                 scsi_disk_put(sdkp);
1451         }
1452 }
1453
1454
1455 #ifdef CONFIG_COMPAT
1456 /*
1457  * This gets directly called from VFS. When the ioctl
1458  * is not recognized we go back to the other translation paths.
1459  */
1460 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
1461                            unsigned int cmd, unsigned long arg)
1462 {
1463         struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1464         int ret;
1465
1466         ret = scsi_verify_blk_ioctl(bdev, cmd);
1467         if (ret < 0)
1468                 return ret;
1469
1470         /*
1471          * If we are in the middle of error recovery, don't let anyone
1472          * else try and use this device.  Also, if error recovery fails, it
1473          * may try and take the device offline, in which case all further
1474          * access to the device is prohibited.
1475          */
1476         if (!scsi_block_when_processing_errors(sdev))
1477                 return -ENODEV;
1478
1479         if (sdev->host->hostt->compat_ioctl) {
1480                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
1481
1482                 return ret;
1483         }
1484
1485         /*
1486          * Let the static ioctl translation table take care of it.
1487          */
1488         return -ENOIOCTLCMD;
1489 }
1490 #endif
1491
1492 static const struct block_device_operations sd_fops = {
1493         .owner                  = THIS_MODULE,
1494         .open                   = sd_open,
1495         .release                = sd_release,
1496         .ioctl                  = sd_ioctl,
1497         .getgeo                 = sd_getgeo,
1498 #ifdef CONFIG_COMPAT
1499         .compat_ioctl           = sd_compat_ioctl,
1500 #endif
1501         .check_events           = sd_check_events,
1502         .revalidate_disk        = sd_revalidate_disk,
1503         .unlock_native_capacity = sd_unlock_native_capacity,
1504 };
1505
1506 /**
1507  *      sd_eh_action - error handling callback
1508  *      @scmd:          sd-issued command that has failed
1509  *      @eh_cmnd:       The command that was sent during error handling
1510  *      @eh_cmnd_len:   Length of eh_cmnd in bytes
1511  *      @eh_disp:       The recovery disposition suggested by the midlayer
1512  *
1513  *      This function is called by the SCSI midlayer upon completion of
1514  *      an error handling command (TEST UNIT READY, START STOP UNIT,
1515  *      etc.) The command sent to the device by the error handler is
1516  *      stored in eh_cmnd. The result of sending the eh command is
1517  *      passed in eh_disp.
1518  **/
1519 static int sd_eh_action(struct scsi_cmnd *scmd, unsigned char *eh_cmnd,
1520                         int eh_cmnd_len, int eh_disp)
1521 {
1522         struct scsi_disk *sdkp = scsi_disk(scmd->request->rq_disk);
1523
1524         if (!scsi_device_online(scmd->device) ||
1525             !scsi_medium_access_command(scmd))
1526                 return eh_disp;
1527
1528         /*
1529          * The device has timed out executing a medium access command.
1530          * However, the TEST UNIT READY command sent during error
1531          * handling completed successfully. Either the device is in the
1532          * process of recovering or has it suffered an internal failure
1533          * that prevents access to the storage medium.
1534          */
1535         if (host_byte(scmd->result) == DID_TIME_OUT && eh_disp == SUCCESS &&
1536             eh_cmnd_len && eh_cmnd[0] == TEST_UNIT_READY)
1537                 sdkp->medium_access_timed_out++;
1538
1539         /*
1540          * If the device keeps failing read/write commands but TEST UNIT
1541          * READY always completes successfully we assume that medium
1542          * access is no longer possible and take the device offline.
1543          */
1544         if (sdkp->medium_access_timed_out >= sdkp->max_medium_access_timeouts) {
1545                 scmd_printk(KERN_ERR, scmd,
1546                             "Medium access timeout failure. Offlining disk!\n");
1547                 scsi_device_set_state(scmd->device, SDEV_OFFLINE);
1548
1549                 return FAILED;
1550         }
1551
1552         return eh_disp;
1553 }
1554
1555 static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
1556 {
1557         u64 start_lba = blk_rq_pos(scmd->request);
1558         u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
1559         u64 bad_lba;
1560         int info_valid;
1561         /*
1562          * resid is optional but mostly filled in.  When it's unused,
1563          * its value is zero, so we assume the whole buffer transferred
1564          */
1565         unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
1566         unsigned int good_bytes;
1567
1568         if (scmd->request->cmd_type != REQ_TYPE_FS)
1569                 return 0;
1570
1571         info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
1572                                              SCSI_SENSE_BUFFERSIZE,
1573                                              &bad_lba);
1574         if (!info_valid)
1575                 return 0;
1576
1577         if (scsi_bufflen(scmd) <= scmd->device->sector_size)
1578                 return 0;
1579
1580         if (scmd->device->sector_size < 512) {
1581                 /* only legitimate sector_size here is 256 */
1582                 start_lba <<= 1;
1583                 end_lba <<= 1;
1584         } else {
1585                 /* be careful ... don't want any overflows */
1586                 u64 factor = scmd->device->sector_size / 512;
1587                 do_div(start_lba, factor);
1588                 do_div(end_lba, factor);
1589         }
1590
1591         /* The bad lba was reported incorrectly, we have no idea where
1592          * the error is.
1593          */
1594         if (bad_lba < start_lba  || bad_lba >= end_lba)
1595                 return 0;
1596
1597         /* This computation should always be done in terms of
1598          * the resolution of the device's medium.
1599          */
1600         good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
1601         return min(good_bytes, transferred);
1602 }
1603
1604 /**
1605  *      sd_done - bottom half handler: called when the lower level
1606  *      driver has completed (successfully or otherwise) a scsi command.
1607  *      @SCpnt: mid-level's per command structure.
1608  *
1609  *      Note: potentially run from within an ISR. Must not block.
1610  **/
1611 static int sd_done(struct scsi_cmnd *SCpnt)
1612 {
1613         int result = SCpnt->result;
1614         unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
1615         struct scsi_sense_hdr sshdr;
1616         struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
1617         struct request *req = SCpnt->request;
1618         int sense_valid = 0;
1619         int sense_deferred = 0;
1620         unsigned char op = SCpnt->cmnd[0];
1621         unsigned char unmap = SCpnt->cmnd[1] & 8;
1622
1623         if (req->cmd_flags & REQ_DISCARD || req->cmd_flags & REQ_WRITE_SAME) {
1624                 if (!result) {
1625                         good_bytes = blk_rq_bytes(req);
1626                         scsi_set_resid(SCpnt, 0);
1627                 } else {
1628                         good_bytes = 0;
1629                         scsi_set_resid(SCpnt, blk_rq_bytes(req));
1630                 }
1631         }
1632
1633         if (result) {
1634                 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
1635                 if (sense_valid)
1636                         sense_deferred = scsi_sense_is_deferred(&sshdr);
1637         }
1638 #ifdef CONFIG_SCSI_LOGGING
1639         SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
1640         if (sense_valid) {
1641                 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
1642                                                    "sd_done: sb[respc,sk,asc,"
1643                                                    "ascq]=%x,%x,%x,%x\n",
1644                                                    sshdr.response_code,
1645                                                    sshdr.sense_key, sshdr.asc,
1646                                                    sshdr.ascq));
1647         }
1648 #endif
1649         if (driver_byte(result) != DRIVER_SENSE &&
1650             (!sense_valid || sense_deferred))
1651                 goto out;
1652
1653         sdkp->medium_access_timed_out = 0;
1654
1655         switch (sshdr.sense_key) {
1656         case HARDWARE_ERROR:
1657         case MEDIUM_ERROR:
1658                 good_bytes = sd_completed_bytes(SCpnt);
1659                 break;
1660         case RECOVERED_ERROR:
1661                 good_bytes = scsi_bufflen(SCpnt);
1662                 break;
1663         case NO_SENSE:
1664                 /* This indicates a false check condition, so ignore it.  An
1665                  * unknown amount of data was transferred so treat it as an
1666                  * error.
1667                  */
1668                 scsi_print_sense("sd", SCpnt);
1669                 SCpnt->result = 0;
1670                 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1671                 break;
1672         case ABORTED_COMMAND:
1673                 if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
1674                         good_bytes = sd_completed_bytes(SCpnt);
1675                 break;
1676         case ILLEGAL_REQUEST:
1677                 if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
1678                         good_bytes = sd_completed_bytes(SCpnt);
1679                 /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
1680                 if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
1681                         switch (op) {
1682                         case UNMAP:
1683                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
1684                                 break;
1685                         case WRITE_SAME_16:
1686                         case WRITE_SAME:
1687                                 if (unmap)
1688                                         sd_config_discard(sdkp, SD_LBP_DISABLE);
1689                                 else {
1690                                         sdkp->device->no_write_same = 1;
1691                                         sd_config_write_same(sdkp);
1692
1693                                         good_bytes = 0;
1694                                         req->__data_len = blk_rq_bytes(req);
1695                                         req->cmd_flags |= REQ_QUIET;
1696                                 }
1697                         }
1698                 }
1699                 break;
1700         default:
1701                 break;
1702         }
1703  out:
1704         if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
1705                 sd_dif_complete(SCpnt, good_bytes);
1706
1707         if (scsi_host_dif_capable(sdkp->device->host, sdkp->protection_type)
1708             == SD_DIF_TYPE2_PROTECTION && SCpnt->cmnd != SCpnt->request->cmd) {
1709
1710                 /* We have to print a failed command here as the
1711                  * extended CDB gets freed before scsi_io_completion()
1712                  * is called.
1713                  */
1714                 if (result)
1715                         scsi_print_command(SCpnt);
1716
1717                 mempool_free(SCpnt->cmnd, sd_cdb_pool);
1718                 SCpnt->cmnd = NULL;
1719                 SCpnt->cmd_len = 0;
1720         }
1721
1722         return good_bytes;
1723 }
1724
1725 /*
1726  * spinup disk - called only in sd_revalidate_disk()
1727  */
1728 static void
1729 sd_spinup_disk(struct scsi_disk *sdkp)
1730 {
1731         unsigned char cmd[10];
1732         unsigned long spintime_expire = 0;
1733         int retries, spintime;
1734         unsigned int the_result;
1735         struct scsi_sense_hdr sshdr;
1736         int sense_valid = 0;
1737
1738         spintime = 0;
1739
1740         /* Spin up drives, as required.  Only do this at boot time */
1741         /* Spinup needs to be done for module loads too. */
1742         do {
1743                 retries = 0;
1744
1745                 do {
1746                         cmd[0] = TEST_UNIT_READY;
1747                         memset((void *) &cmd[1], 0, 9);
1748
1749                         the_result = scsi_execute_req(sdkp->device, cmd,
1750                                                       DMA_NONE, NULL, 0,
1751                                                       &sshdr, SD_TIMEOUT,
1752                                                       SD_MAX_RETRIES, NULL);
1753
1754                         /*
1755                          * If the drive has indicated to us that it
1756                          * doesn't have any media in it, don't bother
1757                          * with any more polling.
1758                          */
1759                         if (media_not_present(sdkp, &sshdr))
1760                                 return;
1761
1762                         if (the_result)
1763                                 sense_valid = scsi_sense_valid(&sshdr);
1764                         retries++;
1765                 } while (retries < 3 &&
1766                          (!scsi_status_is_good(the_result) ||
1767                           ((driver_byte(the_result) & DRIVER_SENSE) &&
1768                           sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1769
1770                 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1771                         /* no sense, TUR either succeeded or failed
1772                          * with a status error */
1773                         if(!spintime && !scsi_status_is_good(the_result)) {
1774                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1775                                 sd_print_result(sdkp, the_result);
1776                         }
1777                         break;
1778                 }
1779
1780                 /*
1781                  * The device does not want the automatic start to be issued.
1782                  */
1783                 if (sdkp->device->no_start_on_add)
1784                         break;
1785
1786                 if (sense_valid && sshdr.sense_key == NOT_READY) {
1787                         if (sshdr.asc == 4 && sshdr.ascq == 3)
1788                                 break;  /* manual intervention required */
1789                         if (sshdr.asc == 4 && sshdr.ascq == 0xb)
1790                                 break;  /* standby */
1791                         if (sshdr.asc == 4 && sshdr.ascq == 0xc)
1792                                 break;  /* unavailable */
1793                         /*
1794                          * Issue command to spin up drive when not ready
1795                          */
1796                         if (!spintime) {
1797                                 sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
1798                                 cmd[0] = START_STOP;
1799                                 cmd[1] = 1;     /* Return immediately */
1800                                 memset((void *) &cmd[2], 0, 8);
1801                                 cmd[4] = 1;     /* Start spin cycle */
1802                                 if (sdkp->device->start_stop_pwr_cond)
1803                                         cmd[4] |= 1 << 4;
1804                                 scsi_execute_req(sdkp->device, cmd, DMA_NONE,
1805                                                  NULL, 0, &sshdr,
1806                                                  SD_TIMEOUT, SD_MAX_RETRIES,
1807                                                  NULL);
1808                                 spintime_expire = jiffies + 100 * HZ;
1809                                 spintime = 1;
1810                         }
1811                         /* Wait 1 second for next try */
1812                         msleep(1000);
1813                         printk(".");
1814
1815                 /*
1816                  * Wait for USB flash devices with slow firmware.
1817                  * Yes, this sense key/ASC combination shouldn't
1818                  * occur here.  It's characteristic of these devices.
1819                  */
1820                 } else if (sense_valid &&
1821                                 sshdr.sense_key == UNIT_ATTENTION &&
1822                                 sshdr.asc == 0x28) {
1823                         if (!spintime) {
1824                                 spintime_expire = jiffies + 5 * HZ;
1825                                 spintime = 1;
1826                         }
1827                         /* Wait 1 second for next try */
1828                         msleep(1000);
1829                 } else {
1830                         /* we don't understand the sense code, so it's
1831                          * probably pointless to loop */
1832                         if(!spintime) {
1833                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1834                                 sd_print_sense_hdr(sdkp, &sshdr);
1835                         }
1836                         break;
1837                 }
1838
1839         } while (spintime && time_before_eq(jiffies, spintime_expire));
1840
1841         if (spintime) {
1842                 if (scsi_status_is_good(the_result))
1843                         printk("ready\n");
1844                 else
1845                         printk("not responding...\n");
1846         }
1847 }
1848
1849
1850 /*
1851  * Determine whether disk supports Data Integrity Field.
1852  */
1853 static int sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
1854 {
1855         struct scsi_device *sdp = sdkp->device;
1856         u8 type;
1857         int ret = 0;
1858
1859         if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
1860                 return ret;
1861
1862         type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
1863
1864         if (type > SD_DIF_TYPE3_PROTECTION)
1865                 ret = -ENODEV;
1866         else if (scsi_host_dif_capable(sdp->host, type))
1867                 ret = 1;
1868
1869         if (sdkp->first_scan || type != sdkp->protection_type)
1870                 switch (ret) {
1871                 case -ENODEV:
1872                         sd_printk(KERN_ERR, sdkp, "formatted with unsupported" \
1873                                   " protection type %u. Disabling disk!\n",
1874                                   type);
1875                         break;
1876                 case 1:
1877                         sd_printk(KERN_NOTICE, sdkp,
1878                                   "Enabling DIF Type %u protection\n", type);
1879                         break;
1880                 case 0:
1881                         sd_printk(KERN_NOTICE, sdkp,
1882                                   "Disabling DIF Type %u protection\n", type);
1883                         break;
1884                 }
1885
1886         sdkp->protection_type = type;
1887
1888         return ret;
1889 }
1890
1891 static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
1892                         struct scsi_sense_hdr *sshdr, int sense_valid,
1893                         int the_result)
1894 {
1895         sd_print_result(sdkp, the_result);
1896         if (driver_byte(the_result) & DRIVER_SENSE)
1897                 sd_print_sense_hdr(sdkp, sshdr);
1898         else
1899                 sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
1900
1901         /*
1902          * Set dirty bit for removable devices if not ready -
1903          * sometimes drives will not report this properly.
1904          */
1905         if (sdp->removable &&
1906             sense_valid && sshdr->sense_key == NOT_READY)
1907                 set_media_not_present(sdkp);
1908
1909         /*
1910          * We used to set media_present to 0 here to indicate no media
1911          * in the drive, but some drives fail read capacity even with
1912          * media present, so we can't do that.
1913          */
1914         sdkp->capacity = 0; /* unknown mapped to zero - as usual */
1915 }
1916
1917 #define RC16_LEN 32
1918 #if RC16_LEN > SD_BUF_SIZE
1919 #error RC16_LEN must not be more than SD_BUF_SIZE
1920 #endif
1921
1922 #define READ_CAPACITY_RETRIES_ON_RESET  10
1923
1924 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
1925                                                 unsigned char *buffer)
1926 {
1927         unsigned char cmd[16];
1928         struct scsi_sense_hdr sshdr;
1929         int sense_valid = 0;
1930         int the_result;
1931         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1932         unsigned int alignment;
1933         unsigned long long lba;
1934         unsigned sector_size;
1935
1936         if (sdp->no_read_capacity_16)
1937                 return -EINVAL;
1938
1939         do {
1940                 memset(cmd, 0, 16);
1941                 cmd[0] = SERVICE_ACTION_IN;
1942                 cmd[1] = SAI_READ_CAPACITY_16;
1943                 cmd[13] = RC16_LEN;
1944                 memset(buffer, 0, RC16_LEN);
1945
1946                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1947                                         buffer, RC16_LEN, &sshdr,
1948                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1949
1950                 if (media_not_present(sdkp, &sshdr))
1951                         return -ENODEV;
1952
1953                 if (the_result) {
1954                         sense_valid = scsi_sense_valid(&sshdr);
1955                         if (sense_valid &&
1956                             sshdr.sense_key == ILLEGAL_REQUEST &&
1957                             (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1958                             sshdr.ascq == 0x00)
1959                                 /* Invalid Command Operation Code or
1960                                  * Invalid Field in CDB, just retry
1961                                  * silently with RC10 */
1962                                 return -EINVAL;
1963                         if (sense_valid &&
1964                             sshdr.sense_key == UNIT_ATTENTION &&
1965                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1966                                 /* Device reset might occur several times,
1967                                  * give it one more chance */
1968                                 if (--reset_retries > 0)
1969                                         continue;
1970                 }
1971                 retries--;
1972
1973         } while (the_result && retries);
1974
1975         if (the_result) {
1976                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY(16) failed\n");
1977                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1978                 return -EINVAL;
1979         }
1980
1981         sector_size = get_unaligned_be32(&buffer[8]);
1982         lba = get_unaligned_be64(&buffer[0]);
1983
1984         if (sd_read_protection_type(sdkp, buffer) < 0) {
1985                 sdkp->capacity = 0;
1986                 return -ENODEV;
1987         }
1988
1989         if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
1990                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1991                         "kernel compiled with support for large block "
1992                         "devices.\n");
1993                 sdkp->capacity = 0;
1994                 return -EOVERFLOW;
1995         }
1996
1997         /* Logical blocks per physical block exponent */
1998         sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
1999
2000         /* Lowest aligned logical block */
2001         alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
2002         blk_queue_alignment_offset(sdp->request_queue, alignment);
2003         if (alignment && sdkp->first_scan)
2004                 sd_printk(KERN_NOTICE, sdkp,
2005                           "physical block alignment offset: %u\n", alignment);
2006
2007         if (buffer[14] & 0x80) { /* LBPME */
2008                 sdkp->lbpme = 1;
2009
2010                 if (buffer[14] & 0x40) /* LBPRZ */
2011                         sdkp->lbprz = 1;
2012
2013                 sd_config_discard(sdkp, SD_LBP_WS16);
2014         }
2015
2016         sdkp->capacity = lba + 1;
2017         return sector_size;
2018 }
2019
2020 static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
2021                                                 unsigned char *buffer)
2022 {
2023         unsigned char cmd[16];
2024         struct scsi_sense_hdr sshdr;
2025         int sense_valid = 0;
2026         int the_result;
2027         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
2028         sector_t lba;
2029         unsigned sector_size;
2030
2031         do {
2032                 cmd[0] = READ_CAPACITY;
2033                 memset(&cmd[1], 0, 9);
2034                 memset(buffer, 0, 8);
2035
2036                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
2037                                         buffer, 8, &sshdr,
2038                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2039
2040                 if (media_not_present(sdkp, &sshdr))
2041                         return -ENODEV;
2042
2043                 if (the_result) {
2044                         sense_valid = scsi_sense_valid(&sshdr);
2045                         if (sense_valid &&
2046                             sshdr.sense_key == UNIT_ATTENTION &&
2047                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
2048                                 /* Device reset might occur several times,
2049                                  * give it one more chance */
2050                                 if (--reset_retries > 0)
2051                                         continue;
2052                 }
2053                 retries--;
2054
2055         } while (the_result && retries);
2056
2057         if (the_result) {
2058                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY failed\n");
2059                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
2060                 return -EINVAL;
2061         }
2062
2063         sector_size = get_unaligned_be32(&buffer[4]);
2064         lba = get_unaligned_be32(&buffer[0]);
2065
2066         if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
2067                 /* Some buggy (usb cardreader) devices return an lba of
2068                    0xffffffff when the want to report a size of 0 (with
2069                    which they really mean no media is present) */
2070                 sdkp->capacity = 0;
2071                 sdkp->physical_block_size = sector_size;
2072                 return sector_size;
2073         }
2074
2075         if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
2076                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
2077                         "kernel compiled with support for large block "
2078                         "devices.\n");
2079                 sdkp->capacity = 0;
2080                 return -EOVERFLOW;
2081         }
2082
2083         sdkp->capacity = lba + 1;
2084         sdkp->physical_block_size = sector_size;
2085         return sector_size;
2086 }
2087
2088 static int sd_try_rc16_first(struct scsi_device *sdp)
2089 {
2090         if (sdp->host->max_cmd_len < 16)
2091                 return 0;
2092         if (sdp->try_rc_10_first)
2093                 return 0;
2094         if (sdp->scsi_level > SCSI_SPC_2)
2095                 return 1;
2096         if (scsi_device_protection(sdp))
2097                 return 1;
2098         return 0;
2099 }
2100
2101 /*
2102  * read disk capacity
2103  */
2104 static void
2105 sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
2106 {
2107         int sector_size;
2108         struct scsi_device *sdp = sdkp->device;
2109         sector_t old_capacity = sdkp->capacity;
2110
2111         if (sd_try_rc16_first(sdp)) {
2112                 sector_size = read_capacity_16(sdkp, sdp, buffer);
2113                 if (sector_size == -EOVERFLOW)
2114                         goto got_data;
2115                 if (sector_size == -ENODEV)
2116                         return;
2117                 if (sector_size < 0)
2118                         sector_size = read_capacity_10(sdkp, sdp, buffer);
2119                 if (sector_size < 0)
2120                         return;
2121         } else {
2122                 sector_size = read_capacity_10(sdkp, sdp, buffer);
2123                 if (sector_size == -EOVERFLOW)
2124                         goto got_data;
2125                 if (sector_size < 0)
2126                         return;
2127                 if ((sizeof(sdkp->capacity) > 4) &&
2128                     (sdkp->capacity > 0xffffffffULL)) {
2129                         int old_sector_size = sector_size;
2130                         sd_printk(KERN_NOTICE, sdkp, "Very big device. "
2131                                         "Trying to use READ CAPACITY(16).\n");
2132                         sector_size = read_capacity_16(sdkp, sdp, buffer);
2133                         if (sector_size < 0) {
2134                                 sd_printk(KERN_NOTICE, sdkp,
2135                                         "Using 0xffffffff as device size\n");
2136                                 sdkp->capacity = 1 + (sector_t) 0xffffffff;
2137                                 sector_size = old_sector_size;
2138                                 goto got_data;
2139                         }
2140                 }
2141         }
2142
2143         /* Some devices are known to return the total number of blocks,
2144          * not the highest block number.  Some devices have versions
2145          * which do this and others which do not.  Some devices we might
2146          * suspect of doing this but we don't know for certain.
2147          *
2148          * If we know the reported capacity is wrong, decrement it.  If
2149          * we can only guess, then assume the number of blocks is even
2150          * (usually true but not always) and err on the side of lowering
2151          * the capacity.
2152          */
2153         if (sdp->fix_capacity ||
2154             (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
2155                 sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
2156                                 "from its reported value: %llu\n",
2157                                 (unsigned long long) sdkp->capacity);
2158                 --sdkp->capacity;
2159         }
2160
2161 got_data:
2162         if (sector_size == 0) {
2163                 sector_size = 512;
2164                 sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
2165                           "assuming 512.\n");
2166         }
2167
2168         if (sector_size != 512 &&
2169             sector_size != 1024 &&
2170             sector_size != 2048 &&
2171             sector_size != 4096 &&
2172             sector_size != 256) {
2173                 sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
2174                           sector_size);
2175                 /*
2176                  * The user might want to re-format the drive with
2177                  * a supported sectorsize.  Once this happens, it
2178                  * would be relatively trivial to set the thing up.
2179                  * For this reason, we leave the thing in the table.
2180                  */
2181                 sdkp->capacity = 0;
2182                 /*
2183                  * set a bogus sector size so the normal read/write
2184                  * logic in the block layer will eventually refuse any
2185                  * request on this device without tripping over power
2186                  * of two sector size assumptions
2187                  */
2188                 sector_size = 512;
2189         }
2190         blk_queue_logical_block_size(sdp->request_queue, sector_size);
2191
2192         {
2193                 char cap_str_2[10], cap_str_10[10];
2194                 u64 sz = (u64)sdkp->capacity << ilog2(sector_size);
2195
2196                 string_get_size(sz, STRING_UNITS_2, cap_str_2,
2197                                 sizeof(cap_str_2));
2198                 string_get_size(sz, STRING_UNITS_10, cap_str_10,
2199                                 sizeof(cap_str_10));
2200
2201                 if (sdkp->first_scan || old_capacity != sdkp->capacity) {
2202                         sd_printk(KERN_NOTICE, sdkp,
2203                                   "%llu %d-byte logical blocks: (%s/%s)\n",
2204                                   (unsigned long long)sdkp->capacity,
2205                                   sector_size, cap_str_10, cap_str_2);
2206
2207                         if (sdkp->physical_block_size != sector_size)
2208                                 sd_printk(KERN_NOTICE, sdkp,
2209                                           "%u-byte physical blocks\n",
2210                                           sdkp->physical_block_size);
2211                 }
2212         }
2213
2214         sdp->use_16_for_rw = (sdkp->capacity > 0xffffffff);
2215
2216         /* Rescale capacity to 512-byte units */
2217         if (sector_size == 4096)
2218                 sdkp->capacity <<= 3;
2219         else if (sector_size == 2048)
2220                 sdkp->capacity <<= 2;
2221         else if (sector_size == 1024)
2222                 sdkp->capacity <<= 1;
2223         else if (sector_size == 256)
2224                 sdkp->capacity >>= 1;
2225
2226         blk_queue_physical_block_size(sdp->request_queue,
2227                                       sdkp->physical_block_size);
2228         sdkp->device->sector_size = sector_size;
2229 }
2230
2231 /* called with buffer of length 512 */
2232 static inline int
2233 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
2234                  unsigned char *buffer, int len, struct scsi_mode_data *data,
2235                  struct scsi_sense_hdr *sshdr)
2236 {
2237         return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
2238                                SD_TIMEOUT, SD_MAX_RETRIES, data,
2239                                sshdr);
2240 }
2241
2242 /*
2243  * read write protect setting, if possible - called only in sd_revalidate_disk()
2244  * called with buffer of length SD_BUF_SIZE
2245  */
2246 static void
2247 sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
2248 {
2249         int res;
2250         struct scsi_device *sdp = sdkp->device;
2251         struct scsi_mode_data data;
2252         int old_wp = sdkp->write_prot;
2253
2254         set_disk_ro(sdkp->disk, 0);
2255         if (sdp->skip_ms_page_3f) {
2256                 sd_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
2257                 return;
2258         }
2259
2260         if (sdp->use_192_bytes_for_3f) {
2261                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
2262         } else {
2263                 /*
2264                  * First attempt: ask for all pages (0x3F), but only 4 bytes.
2265                  * We have to start carefully: some devices hang if we ask
2266                  * for more than is available.
2267                  */
2268                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
2269
2270                 /*
2271                  * Second attempt: ask for page 0 When only page 0 is
2272                  * implemented, a request for page 3F may return Sense Key
2273                  * 5: Illegal Request, Sense Code 24: Invalid field in
2274                  * CDB.
2275                  */
2276                 if (!scsi_status_is_good(res))
2277                         res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
2278
2279                 /*
2280                  * Third attempt: ask 255 bytes, as we did earlier.
2281                  */
2282                 if (!scsi_status_is_good(res))
2283                         res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
2284                                                &data, NULL);
2285         }
2286
2287         if (!scsi_status_is_good(res)) {
2288                 sd_printk(KERN_WARNING, sdkp,
2289                           "Test WP failed, assume Write Enabled\n");
2290         } else {
2291                 sdkp->write_prot = ((data.device_specific & 0x80) != 0);
2292                 set_disk_ro(sdkp->disk, sdkp->write_prot);
2293                 if (sdkp->first_scan || old_wp != sdkp->write_prot) {
2294                         sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
2295                                   sdkp->write_prot ? "on" : "off");
2296                         sd_printk(KERN_DEBUG, sdkp,
2297                                   "Mode Sense: %02x %02x %02x %02x\n",
2298                                   buffer[0], buffer[1], buffer[2], buffer[3]);
2299                 }
2300         }
2301 }
2302
2303 /*
2304  * sd_read_cache_type - called only from sd_revalidate_disk()
2305  * called with buffer of length SD_BUF_SIZE
2306  */
2307 static void
2308 sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
2309 {
2310         int len = 0, res;
2311         struct scsi_device *sdp = sdkp->device;
2312
2313         int dbd;
2314         int modepage;
2315         int first_len;
2316         struct scsi_mode_data data;
2317         struct scsi_sense_hdr sshdr;
2318         int old_wce = sdkp->WCE;
2319         int old_rcd = sdkp->RCD;
2320         int old_dpofua = sdkp->DPOFUA;
2321
2322         first_len = 4;
2323         if (sdp->skip_ms_page_8) {
2324                 if (sdp->type == TYPE_RBC)
2325                         goto defaults;
2326                 else {
2327                         if (sdp->skip_ms_page_3f)
2328                                 goto defaults;
2329                         modepage = 0x3F;
2330                         if (sdp->use_192_bytes_for_3f)
2331                                 first_len = 192;
2332                         dbd = 0;
2333                 }
2334         } else if (sdp->type == TYPE_RBC) {
2335                 modepage = 6;
2336                 dbd = 8;
2337         } else {
2338                 modepage = 8;
2339                 dbd = 0;
2340         }
2341
2342         /* cautiously ask */
2343         res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
2344                         &data, &sshdr);
2345
2346         if (!scsi_status_is_good(res))
2347                 goto bad_sense;
2348
2349         if (!data.header_length) {
2350                 modepage = 6;
2351                 first_len = 0;
2352                 sd_printk(KERN_ERR, sdkp, "Missing header in MODE_SENSE response\n");
2353         }
2354
2355         /* that went OK, now ask for the proper length */
2356         len = data.length;
2357
2358         /*
2359          * We're only interested in the first three bytes, actually.
2360          * But the data cache page is defined for the first 20.
2361          */
2362         if (len < 3)
2363                 goto bad_sense;
2364         else if (len > SD_BUF_SIZE) {
2365                 sd_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
2366                           "data from %d to %d bytes\n", len, SD_BUF_SIZE);
2367                 len = SD_BUF_SIZE;
2368         }
2369         if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
2370                 len = 192;
2371
2372         /* Get the data */
2373         if (len > first_len)
2374                 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
2375                                 &data, &sshdr);
2376
2377         if (scsi_status_is_good(res)) {
2378                 int offset = data.header_length + data.block_descriptor_length;
2379
2380                 while (offset < len) {
2381                         u8 page_code = buffer[offset] & 0x3F;
2382                         u8 spf       = buffer[offset] & 0x40;
2383
2384                         if (page_code == 8 || page_code == 6) {
2385                                 /* We're interested only in the first 3 bytes.
2386                                  */
2387                                 if (len - offset <= 2) {
2388                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2389                                                   "mode parameter data\n");
2390                                         goto defaults;
2391                                 } else {
2392                                         modepage = page_code;
2393                                         goto Page_found;
2394                                 }
2395                         } else {
2396                                 /* Go to the next page */
2397                                 if (spf && len - offset > 3)
2398                                         offset += 4 + (buffer[offset+2] << 8) +
2399                                                 buffer[offset+3];
2400                                 else if (!spf && len - offset > 1)
2401                                         offset += 2 + buffer[offset+1];
2402                                 else {
2403                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2404                                                   "mode parameter data\n");
2405                                         goto defaults;
2406                                 }
2407                         }
2408                 }
2409
2410                 if (modepage == 0x3F) {
2411                         sd_printk(KERN_ERR, sdkp, "No Caching mode page "
2412                                   "present\n");
2413                         goto defaults;
2414                 } else if ((buffer[offset] & 0x3f) != modepage) {
2415                         sd_printk(KERN_ERR, sdkp, "Got wrong page\n");
2416                         goto defaults;
2417                 }
2418         Page_found:
2419                 if (modepage == 8) {
2420                         sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
2421                         sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
2422                 } else {
2423                         sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
2424                         sdkp->RCD = 0;
2425                 }
2426
2427                 sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
2428                 if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
2429                         sd_printk(KERN_NOTICE, sdkp,
2430                                   "Uses READ/WRITE(6), disabling FUA\n");
2431                         sdkp->DPOFUA = 0;
2432                 }
2433
2434                 if (sdkp->first_scan || old_wce != sdkp->WCE ||
2435                     old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
2436                         sd_printk(KERN_NOTICE, sdkp,
2437                                   "Write cache: %s, read cache: %s, %s\n",
2438                                   sdkp->WCE ? "enabled" : "disabled",
2439                                   sdkp->RCD ? "disabled" : "enabled",
2440                                   sdkp->DPOFUA ? "supports DPO and FUA"
2441                                   : "doesn't support DPO or FUA");
2442
2443                 return;
2444         }
2445
2446 bad_sense:
2447         if (scsi_sense_valid(&sshdr) &&
2448             sshdr.sense_key == ILLEGAL_REQUEST &&
2449             sshdr.asc == 0x24 && sshdr.ascq == 0x0)
2450                 /* Invalid field in CDB */
2451                 sd_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
2452         else
2453                 sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n");
2454
2455 defaults:
2456         if (sdp->wce_default_on) {
2457                 sd_printk(KERN_NOTICE, sdkp, "Assuming drive cache: write back\n");
2458                 sdkp->WCE = 1;
2459         } else {
2460                 sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n");
2461                 sdkp->WCE = 0;
2462         }
2463         sdkp->RCD = 0;
2464         sdkp->DPOFUA = 0;
2465 }
2466
2467 /*
2468  * The ATO bit indicates whether the DIF application tag is available
2469  * for use by the operating system.
2470  */
2471 static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
2472 {
2473         int res, offset;
2474         struct scsi_device *sdp = sdkp->device;
2475         struct scsi_mode_data data;
2476         struct scsi_sense_hdr sshdr;
2477
2478         if (sdp->type != TYPE_DISK)
2479                 return;
2480
2481         if (sdkp->protection_type == 0)
2482                 return;
2483
2484         res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
2485                               SD_MAX_RETRIES, &data, &sshdr);
2486
2487         if (!scsi_status_is_good(res) || !data.header_length ||
2488             data.length < 6) {
2489                 sd_printk(KERN_WARNING, sdkp,
2490                           "getting Control mode page failed, assume no ATO\n");
2491
2492                 if (scsi_sense_valid(&sshdr))
2493                         sd_print_sense_hdr(sdkp, &sshdr);
2494
2495                 return;
2496         }
2497
2498         offset = data.header_length + data.block_descriptor_length;
2499
2500         if ((buffer[offset] & 0x3f) != 0x0a) {
2501                 sd_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
2502                 return;
2503         }
2504
2505         if ((buffer[offset + 5] & 0x80) == 0)
2506                 return;
2507
2508         sdkp->ATO = 1;
2509
2510         return;
2511 }
2512
2513 /**
2514  * sd_read_block_limits - Query disk device for preferred I/O sizes.
2515  * @disk: disk to query
2516  */
2517 static void sd_read_block_limits(struct scsi_disk *sdkp)
2518 {
2519         unsigned int sector_sz = sdkp->device->sector_size;
2520         const int vpd_len = 64;
2521         unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
2522
2523         if (!buffer ||
2524             /* Block Limits VPD */
2525             scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
2526                 goto out;
2527
2528         blk_queue_io_min(sdkp->disk->queue,
2529                          get_unaligned_be16(&buffer[6]) * sector_sz);
2530         blk_queue_io_opt(sdkp->disk->queue,
2531                          get_unaligned_be32(&buffer[12]) * sector_sz);
2532
2533         if (buffer[3] == 0x3c) {
2534                 unsigned int lba_count, desc_count;
2535
2536                 sdkp->max_ws_blocks = (u32)get_unaligned_be64(&buffer[36]);
2537
2538                 if (!sdkp->lbpme)
2539                         goto out;
2540
2541                 lba_count = get_unaligned_be32(&buffer[20]);
2542                 desc_count = get_unaligned_be32(&buffer[24]);
2543
2544                 if (lba_count && desc_count)
2545                         sdkp->max_unmap_blocks = lba_count;
2546
2547                 sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
2548
2549                 if (buffer[32] & 0x80)
2550                         sdkp->unmap_alignment =
2551                                 get_unaligned_be32(&buffer[32]) & ~(1 << 31);
2552
2553                 if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
2554
2555                         if (sdkp->max_unmap_blocks)
2556                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2557                         else
2558                                 sd_config_discard(sdkp, SD_LBP_WS16);
2559
2560                 } else {        /* LBP VPD page tells us what to use */
2561
2562                         if (sdkp->lbpu && sdkp->max_unmap_blocks)
2563                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2564                         else if (sdkp->lbpws)
2565                                 sd_config_discard(sdkp, SD_LBP_WS16);
2566                         else if (sdkp->lbpws10)
2567                                 sd_config_discard(sdkp, SD_LBP_WS10);
2568                         else
2569                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
2570                 }
2571         }
2572
2573  out:
2574         kfree(buffer);
2575 }
2576
2577 /**
2578  * sd_read_block_characteristics - Query block dev. characteristics
2579  * @disk: disk to query
2580  */
2581 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
2582 {
2583         unsigned char *buffer;
2584         u16 rot;
2585         const int vpd_len = 64;
2586
2587         buffer = kmalloc(vpd_len, GFP_KERNEL);
2588
2589         if (!buffer ||
2590             /* Block Device Characteristics VPD */
2591             scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
2592                 goto out;
2593
2594         rot = get_unaligned_be16(&buffer[4]);
2595
2596         if (rot == 1)
2597                 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
2598
2599  out:
2600         kfree(buffer);
2601 }
2602
2603 /**
2604  * sd_read_block_provisioning - Query provisioning VPD page
2605  * @disk: disk to query
2606  */
2607 static void sd_read_block_provisioning(struct scsi_disk *sdkp)
2608 {
2609         unsigned char *buffer;
2610         const int vpd_len = 8;
2611
2612         if (sdkp->lbpme == 0)
2613                 return;
2614
2615         buffer = kmalloc(vpd_len, GFP_KERNEL);
2616
2617         if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
2618                 goto out;
2619
2620         sdkp->lbpvpd    = 1;
2621         sdkp->lbpu      = (buffer[5] >> 7) & 1; /* UNMAP */
2622         sdkp->lbpws     = (buffer[5] >> 6) & 1; /* WRITE SAME(16) with UNMAP */
2623         sdkp->lbpws10   = (buffer[5] >> 5) & 1; /* WRITE SAME(10) with UNMAP */
2624
2625  out:
2626         kfree(buffer);
2627 }
2628
2629 static void sd_read_write_same(struct scsi_disk *sdkp, unsigned char *buffer)
2630 {
2631         if (scsi_report_opcode(sdkp->device, buffer, SD_BUF_SIZE,
2632                                WRITE_SAME_16))
2633                 sdkp->ws16 = 1;
2634 }
2635
2636 static int sd_try_extended_inquiry(struct scsi_device *sdp)
2637 {
2638         /*
2639          * Although VPD inquiries can go to SCSI-2 type devices,
2640          * some USB ones crash on receiving them, and the pages
2641          * we currently ask for are for SPC-3 and beyond
2642          */
2643         if (sdp->scsi_level > SCSI_SPC_2 && !sdp->skip_vpd_pages)
2644                 return 1;
2645         return 0;
2646 }
2647
2648 /**
2649  *      sd_revalidate_disk - called the first time a new disk is seen,
2650  *      performs disk spin up, read_capacity, etc.
2651  *      @disk: struct gendisk we care about
2652  **/
2653 static int sd_revalidate_disk(struct gendisk *disk)
2654 {
2655         struct scsi_disk *sdkp = scsi_disk(disk);
2656         struct scsi_device *sdp = sdkp->device;
2657         unsigned char *buffer;
2658         unsigned flush = 0;
2659
2660         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
2661                                       "sd_revalidate_disk\n"));
2662
2663         /*
2664          * If the device is offline, don't try and read capacity or any
2665          * of the other niceties.
2666          */
2667         if (!scsi_device_online(sdp))
2668                 goto out;
2669
2670         buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
2671         if (!buffer) {
2672                 sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
2673                           "allocation failure.\n");
2674                 goto out;
2675         }
2676
2677         sd_spinup_disk(sdkp);
2678
2679         /*
2680          * Without media there is no reason to ask; moreover, some devices
2681          * react badly if we do.
2682          */
2683         if (sdkp->media_present) {
2684                 sd_read_capacity(sdkp, buffer);
2685
2686                 if (sd_try_extended_inquiry(sdp)) {
2687                         sd_read_block_provisioning(sdkp);
2688                         sd_read_block_limits(sdkp);
2689                         sd_read_block_characteristics(sdkp);
2690                 }
2691
2692                 sd_read_write_protect_flag(sdkp, buffer);
2693                 sd_read_cache_type(sdkp, buffer);
2694                 sd_read_app_tag_own(sdkp, buffer);
2695                 sd_read_write_same(sdkp, buffer);
2696         }
2697
2698         sdkp->first_scan = 0;
2699
2700         /*
2701          * We now have all cache related info, determine how we deal
2702          * with flush requests.
2703          */
2704         if (sdkp->WCE) {
2705                 flush |= REQ_FLUSH;
2706                 if (sdkp->DPOFUA)
2707                         flush |= REQ_FUA;
2708         }
2709
2710         blk_queue_flush(sdkp->disk->queue, flush);
2711
2712         set_capacity(disk, sdkp->capacity);
2713         sd_config_write_same(sdkp);
2714         kfree(buffer);
2715
2716  out:
2717         return 0;
2718 }
2719
2720 /**
2721  *      sd_unlock_native_capacity - unlock native capacity
2722  *      @disk: struct gendisk to set capacity for
2723  *
2724  *      Block layer calls this function if it detects that partitions
2725  *      on @disk reach beyond the end of the device.  If the SCSI host
2726  *      implements ->unlock_native_capacity() method, it's invoked to
2727  *      give it a chance to adjust the device capacity.
2728  *
2729  *      CONTEXT:
2730  *      Defined by block layer.  Might sleep.
2731  */
2732 static void sd_unlock_native_capacity(struct gendisk *disk)
2733 {
2734         struct scsi_device *sdev = scsi_disk(disk)->device;
2735
2736         if (sdev->host->hostt->unlock_native_capacity)
2737                 sdev->host->hostt->unlock_native_capacity(sdev);
2738 }
2739
2740 /**
2741  *      sd_format_disk_name - format disk name
2742  *      @prefix: name prefix - ie. "sd" for SCSI disks
2743  *      @index: index of the disk to format name for
2744  *      @buf: output buffer
2745  *      @buflen: length of the output buffer
2746  *
2747  *      SCSI disk names starts at sda.  The 26th device is sdz and the
2748  *      27th is sdaa.  The last one for two lettered suffix is sdzz
2749  *      which is followed by sdaaa.
2750  *
2751  *      This is basically 26 base counting with one extra 'nil' entry
2752  *      at the beginning from the second digit on and can be
2753  *      determined using similar method as 26 base conversion with the
2754  *      index shifted -1 after each digit is computed.
2755  *
2756  *      CONTEXT:
2757  *      Don't care.
2758  *
2759  *      RETURNS:
2760  *      0 on success, -errno on failure.
2761  */
2762 static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
2763 {
2764         const int base = 'z' - 'a' + 1;
2765         char *begin = buf + strlen(prefix);
2766         char *end = buf + buflen;
2767         char *p;
2768         int unit;
2769
2770         p = end - 1;
2771         *p = '\0';
2772         unit = base;
2773         do {
2774                 if (p == begin)
2775                         return -EINVAL;
2776                 *--p = 'a' + (index % unit);
2777                 index = (index / unit) - 1;
2778         } while (index >= 0);
2779
2780         memmove(begin, p, end - p);
2781         memcpy(buf, prefix, strlen(prefix));
2782
2783         return 0;
2784 }
2785
2786 /*
2787  * The asynchronous part of sd_probe
2788  */
2789 static void sd_probe_async(void *data, async_cookie_t cookie)
2790 {
2791         struct scsi_disk *sdkp = data;
2792         struct scsi_device *sdp;
2793         struct gendisk *gd;
2794         u32 index;
2795         struct device *dev;
2796
2797         sdp = sdkp->device;
2798         gd = sdkp->disk;
2799         index = sdkp->index;
2800         dev = &sdp->sdev_gendev;
2801
2802         gd->major = sd_major((index & 0xf0) >> 4);
2803         gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
2804         gd->minors = SD_MINORS;
2805
2806         gd->fops = &sd_fops;
2807         gd->private_data = &sdkp->driver;
2808         gd->queue = sdkp->device->request_queue;
2809
2810         /* defaults, until the device tells us otherwise */
2811         sdp->sector_size = 512;
2812         sdkp->capacity = 0;
2813         sdkp->media_present = 1;
2814         sdkp->write_prot = 0;
2815         sdkp->WCE = 0;
2816         sdkp->RCD = 0;
2817         sdkp->ATO = 0;
2818         sdkp->first_scan = 1;
2819         sdkp->max_medium_access_timeouts = SD_MAX_MEDIUM_TIMEOUTS;
2820
2821         sd_revalidate_disk(gd);
2822
2823         blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
2824         blk_queue_unprep_rq(sdp->request_queue, sd_unprep_fn);
2825
2826         gd->driverfs_dev = &sdp->sdev_gendev;
2827         gd->flags = GENHD_FL_EXT_DEVT;
2828         if (sdp->removable) {
2829                 gd->flags |= GENHD_FL_REMOVABLE;
2830                 gd->events |= DISK_EVENT_MEDIA_CHANGE;
2831         }
2832
2833         add_disk(gd);
2834         if (sdkp->capacity)
2835                 sd_dif_config_host(sdkp);
2836
2837         sd_revalidate_disk(gd);
2838
2839         sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
2840                   sdp->removable ? "removable " : "");
2841         scsi_autopm_put_device(sdp);
2842         put_device(&sdkp->dev);
2843 }
2844
2845 /**
2846  *      sd_probe - called during driver initialization and whenever a
2847  *      new scsi device is attached to the system. It is called once
2848  *      for each scsi device (not just disks) present.
2849  *      @dev: pointer to device object
2850  *
2851  *      Returns 0 if successful (or not interested in this scsi device
2852  *      (e.g. scanner)); 1 when there is an error.
2853  *
2854  *      Note: this function is invoked from the scsi mid-level.
2855  *      This function sets up the mapping between a given
2856  *      <host,channel,id,lun> (found in sdp) and new device name
2857  *      (e.g. /dev/sda). More precisely it is the block device major
2858  *      and minor number that is chosen here.
2859  *
2860  *      Assume sd_probe is not re-entrant (for time being)
2861  *      Also think about sd_probe() and sd_remove() running coincidentally.
2862  **/
2863 static int sd_probe(struct device *dev)
2864 {
2865         struct scsi_device *sdp = to_scsi_device(dev);
2866         struct scsi_disk *sdkp;
2867         struct gendisk *gd;
2868         int index;
2869         int error;
2870
2871         error = -ENODEV;
2872         if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
2873                 goto out;
2874
2875         SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
2876                                         "sd_probe\n"));
2877
2878         error = -ENOMEM;
2879         sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
2880         if (!sdkp)
2881                 goto out;
2882
2883         gd = alloc_disk(SD_MINORS);
2884         if (!gd)
2885                 goto out_free;
2886
2887         do {
2888                 if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
2889                         goto out_put;
2890
2891                 spin_lock(&sd_index_lock);
2892                 error = ida_get_new(&sd_index_ida, &index);
2893                 spin_unlock(&sd_index_lock);
2894         } while (error == -EAGAIN);
2895
2896         if (error) {
2897                 sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
2898                 goto out_put;
2899         }
2900
2901         error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
2902         if (error) {
2903                 sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name length exceeded.\n");
2904                 goto out_free_index;
2905         }
2906
2907         sdkp->device = sdp;
2908         sdkp->driver = &sd_template;
2909         sdkp->disk = gd;
2910         sdkp->index = index;
2911         atomic_set(&sdkp->openers, 0);
2912         atomic_set(&sdkp->device->ioerr_cnt, 0);
2913
2914         if (!sdp->request_queue->rq_timeout) {
2915                 if (sdp->type != TYPE_MOD)
2916                         blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
2917                 else
2918                         blk_queue_rq_timeout(sdp->request_queue,
2919                                              SD_MOD_TIMEOUT);
2920         }
2921
2922         device_initialize(&sdkp->dev);
2923         sdkp->dev.parent = dev;
2924         sdkp->dev.class = &sd_disk_class;
2925         dev_set_name(&sdkp->dev, dev_name(dev));
2926
2927         if (device_add(&sdkp->dev))
2928                 goto out_free_index;
2929
2930         get_device(dev);
2931         dev_set_drvdata(dev, sdkp);
2932
2933         get_device(&sdkp->dev); /* prevent release before async_schedule */
2934         async_schedule_domain(sd_probe_async, sdkp, &scsi_sd_probe_domain);
2935
2936         return 0;
2937
2938  out_free_index:
2939         spin_lock(&sd_index_lock);
2940         ida_remove(&sd_index_ida, index);
2941         spin_unlock(&sd_index_lock);
2942  out_put:
2943         put_disk(gd);
2944  out_free:
2945         kfree(sdkp);
2946  out:
2947         return error;
2948 }
2949
2950 /**
2951  *      sd_remove - called whenever a scsi disk (previously recognized by
2952  *      sd_probe) is detached from the system. It is called (potentially
2953  *      multiple times) during sd module unload.
2954  *      @sdp: pointer to mid level scsi device object
2955  *
2956  *      Note: this function is invoked from the scsi mid-level.
2957  *      This function potentially frees up a device name (e.g. /dev/sdc)
2958  *      that could be re-used by a subsequent sd_probe().
2959  *      This function is not called when the built-in sd driver is "exit-ed".
2960  **/
2961 static int sd_remove(struct device *dev)
2962 {
2963         struct scsi_disk *sdkp;
2964
2965         sdkp = dev_get_drvdata(dev);
2966         scsi_autopm_get_device(sdkp->device);
2967
2968         async_synchronize_full_domain(&scsi_sd_probe_domain);
2969         blk_queue_prep_rq(sdkp->device->request_queue, scsi_prep_fn);
2970         blk_queue_unprep_rq(sdkp->device->request_queue, NULL);
2971         device_del(&sdkp->dev);
2972         del_gendisk(sdkp->disk);
2973         sd_shutdown(dev);
2974
2975         mutex_lock(&sd_ref_mutex);
2976         dev_set_drvdata(dev, NULL);
2977         put_device(&sdkp->dev);
2978         mutex_unlock(&sd_ref_mutex);
2979
2980         return 0;
2981 }
2982
2983 /**
2984  *      scsi_disk_release - Called to free the scsi_disk structure
2985  *      @dev: pointer to embedded class device
2986  *
2987  *      sd_ref_mutex must be held entering this routine.  Because it is
2988  *      called on last put, you should always use the scsi_disk_get()
2989  *      scsi_disk_put() helpers which manipulate the semaphore directly
2990  *      and never do a direct put_device.
2991  **/
2992 static void scsi_disk_release(struct device *dev)
2993 {
2994         struct scsi_disk *sdkp = to_scsi_disk(dev);
2995         struct gendisk *disk = sdkp->disk;
2996
2997         spin_lock(&sd_index_lock);
2998         ida_remove(&sd_index_ida, sdkp->index);
2999         spin_unlock(&sd_index_lock);
3000
3001         disk->private_data = NULL;
3002         put_disk(disk);
3003         put_device(&sdkp->device->sdev_gendev);
3004
3005         kfree(sdkp);
3006 }
3007
3008 static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
3009 {
3010         unsigned char cmd[6] = { START_STOP };  /* START_VALID */
3011         struct scsi_sense_hdr sshdr;
3012         struct scsi_device *sdp = sdkp->device;
3013         int res;
3014
3015         if (start)
3016                 cmd[4] |= 1;    /* START */
3017
3018         if (sdp->start_stop_pwr_cond)
3019                 cmd[4] |= start ? 1 << 4 : 3 << 4;      /* Active or Standby */
3020
3021         if (!scsi_device_online(sdp))
3022                 return -ENODEV;
3023
3024         res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
3025                                SD_TIMEOUT, SD_MAX_RETRIES, NULL);
3026         if (res) {
3027                 sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n");
3028                 sd_print_result(sdkp, res);
3029                 if (driver_byte(res) & DRIVER_SENSE)
3030                         sd_print_sense_hdr(sdkp, &sshdr);
3031         }
3032
3033         return res;
3034 }
3035
3036 /*
3037  * Send a SYNCHRONIZE CACHE instruction down to the device through
3038  * the normal SCSI command structure.  Wait for the command to
3039  * complete.
3040  */
3041 static void sd_shutdown(struct device *dev)
3042 {
3043         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
3044
3045         if (!sdkp)
3046                 return;         /* this can happen */
3047
3048         if (pm_runtime_suspended(dev))
3049                 goto exit;
3050
3051         if (sdkp->WCE) {
3052                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
3053                 sd_sync_cache(sdkp);
3054         }
3055
3056         if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
3057                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
3058                 sd_start_stop_device(sdkp, 0);
3059         }
3060
3061 exit:
3062         scsi_disk_put(sdkp);
3063 }
3064
3065 static int sd_suspend(struct device *dev)
3066 {
3067         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
3068         int ret = 0;
3069
3070         if (!sdkp)
3071                 return 0;       /* this can happen */
3072
3073         if (sdkp->WCE) {
3074                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
3075                 ret = sd_sync_cache(sdkp);
3076                 if (ret)
3077                         goto done;
3078         }
3079
3080         if (sdkp->device->manage_start_stop) {
3081                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
3082                 ret = sd_start_stop_device(sdkp, 0);
3083         }
3084
3085 done:
3086         scsi_disk_put(sdkp);
3087         return ret;
3088 }
3089
3090 static int sd_resume(struct device *dev)
3091 {
3092         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
3093         int ret = 0;
3094
3095         if (!sdkp->device->manage_start_stop)
3096                 goto done;
3097
3098         sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
3099         ret = sd_start_stop_device(sdkp, 1);
3100
3101 done:
3102         scsi_disk_put(sdkp);
3103         return ret;
3104 }
3105
3106 /**
3107  *      init_sd - entry point for this driver (both when built in or when
3108  *      a module).
3109  *
3110  *      Note: this function registers this driver with the scsi mid-level.
3111  **/
3112 static int __init init_sd(void)
3113 {
3114         int majors = 0, i, err;
3115
3116         SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
3117
3118         for (i = 0; i < SD_MAJORS; i++)
3119                 if (register_blkdev(sd_major(i), "sd") == 0)
3120                         majors++;
3121
3122         if (!majors)
3123                 return -ENODEV;
3124
3125         err = class_register(&sd_disk_class);
3126         if (err)
3127                 goto err_out;
3128
3129         sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
3130                                          0, 0, NULL);
3131         if (!sd_cdb_cache) {
3132                 printk(KERN_ERR "sd: can't init extended cdb cache\n");
3133                 goto err_out_class;
3134         }
3135
3136         sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
3137         if (!sd_cdb_pool) {
3138                 printk(KERN_ERR "sd: can't init extended cdb pool\n");
3139                 goto err_out_cache;
3140         }
3141
3142         err = scsi_register_driver(&sd_template.gendrv);
3143         if (err)
3144                 goto err_out_driver;
3145
3146         return 0;
3147
3148 err_out_driver:
3149         mempool_destroy(sd_cdb_pool);
3150
3151 err_out_cache:
3152         kmem_cache_destroy(sd_cdb_cache);
3153
3154 err_out_class:
3155         class_unregister(&sd_disk_class);
3156 err_out:
3157         for (i = 0; i < SD_MAJORS; i++)
3158                 unregister_blkdev(sd_major(i), "sd");
3159         return err;
3160 }
3161
3162 /**
3163  *      exit_sd - exit point for this driver (when it is a module).
3164  *
3165  *      Note: this function unregisters this driver from the scsi mid-level.
3166  **/
3167 static void __exit exit_sd(void)
3168 {
3169         int i;
3170
3171         SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
3172
3173         scsi_unregister_driver(&sd_template.gendrv);
3174         mempool_destroy(sd_cdb_pool);
3175         kmem_cache_destroy(sd_cdb_cache);
3176
3177         class_unregister(&sd_disk_class);
3178
3179         for (i = 0; i < SD_MAJORS; i++)
3180                 unregister_blkdev(sd_major(i), "sd");
3181 }
3182
3183 module_init(init_sd);
3184 module_exit(exit_sd);
3185
3186 static void sd_print_sense_hdr(struct scsi_disk *sdkp,
3187                                struct scsi_sense_hdr *sshdr)
3188 {
3189         sd_printk(KERN_INFO, sdkp, " ");
3190         scsi_show_sense_hdr(sshdr);
3191         sd_printk(KERN_INFO, sdkp, " ");
3192         scsi_show_extd_sense(sshdr->asc, sshdr->ascq);
3193 }
3194
3195 static void sd_print_result(struct scsi_disk *sdkp, int result)
3196 {
3197         sd_printk(KERN_INFO, sdkp, " ");
3198         scsi_show_result(result);
3199 }
3200