drivers/scsi/sd.c

   1 /*
   2  *      sd.c Copyright (C) 1992 Drew Eckhardt
   3  *           Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
   4  *
   5  *      Linux scsi disk driver
   6  *              Initial versions: Drew Eckhardt
   7  *              Subsequent revisions: Eric Youngdale
   8  *      Modification history:
   9  *       - Drew Eckhardt <drew@colorado.edu> original
  10  *       - Eric Youngdale <eric@andante.org> add scatter-gather, multiple
  11  *         outstanding request, and other enhancements.
  12  *         Support loadable low-level scsi drivers.
  13  *       - Jirka Hanika <geo@ff.cuni.cz> support more scsi disks using
  14  *         eight major numbers.
  15  *       - Richard Gooch <rgooch@atnf.csiro.au> support devfs.
  16  *       - Torben Mathiasen <tmm@image.dk> Resource allocation fixes in
  17  *         sd_init and cleanups.
  18  *       - Alex Davis <letmein@erols.com> Fix problem where partition info
  19  *         not being read in sd_open. Fix problem where removable media
  20  *         could be ejected after sd_open.
  21  *       - Douglas Gilbert <dgilbert@interlog.com> cleanup for lk 2.5.x
  22  *       - Badari Pulavarty <pbadari@us.ibm.com>, Matthew Wilcox
  23  *         <willy@debian.org>, Kurt Garloff <garloff@suse.de>:
  24  *         Support 32k/1M disks.
  25  *
  26  *      Logging policy (needs CONFIG_SCSI_LOGGING defined):
  27  *       - setting up transfer: SCSI_LOG_HLQUEUE levels 1 and 2
  28  *       - end of transfer (bh + scsi_lib): SCSI_LOG_HLCOMPLETE level 1
  29  *       - entering sd_ioctl: SCSI_LOG_IOCTL level 1
  30  *       - entering other commands: SCSI_LOG_HLQUEUE level 3
  31  *      Note: when the logging level is set by the user, it must be greater
  32  *      than the level indicated above to trigger output.
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/fs.h>
  37 #include <linux/kernel.h>
  38 #include <linux/mm.h>
  39 #include <linux/bio.h>
  40 #include <linux/genhd.h>
  41 #include <linux/hdreg.h>
  42 #include <linux/errno.h>
  43 #include <linux/idr.h>
  44 #include <linux/interrupt.h>
  45 #include <linux/init.h>
  46 #include <linux/blkdev.h>
  47 #include <linux/blkpg.h>
  48 #include <linux/delay.h>
  49 #include <linux/mutex.h>
  50 #include <linux/string_helpers.h>
  51 #include <linux/async.h>
  52 #include <linux/slab.h>
  53 #include <asm/uaccess.h>
  54 #include <asm/unaligned.h>
  55
  56 #include <scsi/scsi.h>
  57 #include <scsi/scsi_cmnd.h>
  58 #include <scsi/scsi_dbg.h>
  59 #include <scsi/scsi_device.h>
  60 #include <scsi/scsi_driver.h>
  61 #include <scsi/scsi_eh.h>
  62 #include <scsi/scsi_host.h>
  63 #include <scsi/scsi_ioctl.h>
  64 #include <scsi/scsicam.h>
  65
  66 #include "sd.h"
  67 #include "scsi_logging.h"
  68
  69 MODULE_AUTHOR("Eric Youngdale");
  70 MODULE_DESCRIPTION("SCSI disk (sd) driver");
  71 MODULE_LICENSE("GPL");
  72
  73 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
  74 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
  75 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
  76 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
  77 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
  78 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
  79 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
  80 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
  81 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
  82 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
  83 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
  84 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
  85 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
  86 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
  87 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
  88 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
  89 MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
  90 MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
  91 MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
  92
  93 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
  94 #define SD_MINORS       16
  95 #else
  96 #define SD_MINORS       0
  97 #endif
  98
  99 static void sd_config_discard(struct scsi_disk *, unsigned int);
 100 static int  sd_revalidate_disk(struct gendisk *);
 101 static void sd_unlock_native_capacity(struct gendisk *disk);
 102 static int  sd_probe(struct device *);
 103 static int  sd_remove(struct device *);
 104 static void sd_shutdown(struct device *);
 105 static int sd_suspend(struct device *, pm_message_t state);
 106 static int sd_resume(struct device *);
 107 static void sd_rescan(struct device *);
 108 static int sd_done(struct scsi_cmnd *);
 109 static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
 110 static void scsi_disk_release(struct device *cdev);
 111 static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
 112 static void sd_print_result(struct scsi_disk *, int);
 113
 114 static DEFINE_SPINLOCK(sd_index_lock);
 115 static DEFINE_IDA(sd_index_ida);
 116
 117 /* This semaphore is used to mediate the 0->1 reference get in the
 118  * face of object destruction (i.e. we can't allow a get on an
 119  * object after last put) */
 120 static DEFINE_MUTEX(sd_ref_mutex);
 121
 122 static struct kmem_cache *sd_cdb_cache;
 123 static mempool_t *sd_cdb_pool;
 124
 125 static const char *sd_cache_types[] = {
 126         "write through", "none", "write back",
 127         "write back, no read (daft)"
 128 };
 129
 130 static ssize_t
 131 sd_store_cache_type(struct device *dev, struct device_attribute *attr,
 132                     const char *buf, size_t count)
 133 {
 134         int i, ct = -1, rcd, wce, sp;
 135         struct scsi_disk *sdkp = to_scsi_disk(dev);
 136         struct scsi_device *sdp = sdkp->device;
 137         char buffer[64];
 138         char *buffer_data;
 139         struct scsi_mode_data data;
 140         struct scsi_sense_hdr sshdr;
 141         static const char temp[] = "temporary ";
 142         int len;
 143
 144         if (sdp->type != TYPE_DISK)
 145                 /* no cache control on RBC devices; theoretically they
 146                  * can do it, but there's probably so many exceptions
 147                  * it's not worth the risk */
 148                 return -EINVAL;
 149
 150         if (strncmp(buf, temp, sizeof(temp) - 1) == 0) {
 151                 buf += sizeof(temp) - 1;
 152                 sdkp->cache_override = 1;
 153         } else {
 154                 sdkp->cache_override = 0;
 155         }
 156
 157         for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
 158                 len = strlen(sd_cache_types[i]);
 159                 if (strncmp(sd_cache_types[i], buf, len) == 0 &&
 160                     buf[len] == '\n') {
 161                         ct = i;
 162                         break;
 163                 }
 164         }
 165         if (ct < 0)
 166                 return -EINVAL;
 167         rcd = ct & 0x01 ? 1 : 0;
 168         wce = ct & 0x02 ? 1 : 0;
 169
 170         if (sdkp->cache_override) {
 171                 sdkp->WCE = wce;
 172                 sdkp->RCD = rcd;
 173                 return count;
 174         }
 175
 176         if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
 177                             SD_MAX_RETRIES, &data, NULL))
 178                 return -EINVAL;
 179         len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
 180                   data.block_descriptor_length);
 181         buffer_data = buffer + data.header_length +
 182                 data.block_descriptor_length;
 183         buffer_data[2] &= ~0x05;
 184         buffer_data[2] |= wce << 2 | rcd;
 185         sp = buffer_data[0] & 0x80 ? 1 : 0;
 186
 187         if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
 188                              SD_MAX_RETRIES, &data, &sshdr)) {
 189                 if (scsi_sense_valid(&sshdr))
 190                         sd_print_sense_hdr(sdkp, &sshdr);
 191                 return -EINVAL;
 192         }
 193         revalidate_disk(sdkp->disk);
 194         return count;
 195 }
 196
 197 static ssize_t
 198 sd_store_manage_start_stop(struct device *dev, struct device_attribute *attr,
 199                            const char *buf, size_t count)
 200 {
 201         struct scsi_disk *sdkp = to_scsi_disk(dev);
 202         struct scsi_device *sdp = sdkp->device;
 203
 204         if (!capable(CAP_SYS_ADMIN))
 205                 return -EACCES;
 206
 207         sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
 208
 209         return count;
 210 }
 211
 212 static ssize_t
 213 sd_store_allow_restart(struct device *dev, struct device_attribute *attr,
 214                        const char *buf, size_t count)
 215 {
 216         struct scsi_disk *sdkp = to_scsi_disk(dev);
 217         struct scsi_device *sdp = sdkp->device;
 218
 219         if (!capable(CAP_SYS_ADMIN))
 220                 return -EACCES;
 221
 222         if (sdp->type != TYPE_DISK)
 223                 return -EINVAL;
 224
 225         sdp->allow_restart = simple_strtoul(buf, NULL, 10);
 226
 227         return count;
 228 }
 229
 230 static ssize_t
 231 sd_show_cache_type(struct device *dev, struct device_attribute *attr,
 232                    char *buf)
 233 {
 234         struct scsi_disk *sdkp = to_scsi_disk(dev);
 235         int ct = sdkp->RCD + 2*sdkp->WCE;
 236
 237         return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
 238 }
 239
 240 static ssize_t
 241 sd_show_fua(struct device *dev, struct device_attribute *attr, char *buf)
 242 {
 243         struct scsi_disk *sdkp = to_scsi_disk(dev);
 244
 245         return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
 246 }
 247
 248 static ssize_t
 249 sd_show_manage_start_stop(struct device *dev, struct device_attribute *attr,
 250                           char *buf)
 251 {
 252         struct scsi_disk *sdkp = to_scsi_disk(dev);
 253         struct scsi_device *sdp = sdkp->device;
 254
 255         return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
 256 }
 257
 258 static ssize_t
 259 sd_show_allow_restart(struct device *dev, struct device_attribute *attr,
 260                       char *buf)
 261 {
 262         struct scsi_disk *sdkp = to_scsi_disk(dev);
 263
 264         return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
 265 }
 266
 267 static ssize_t
 268 sd_show_protection_type(struct device *dev, struct device_attribute *attr,
 269                         char *buf)
 270 {
 271         struct scsi_disk *sdkp = to_scsi_disk(dev);
 272
 273         return snprintf(buf, 20, "%u\n", sdkp->protection_type);
 274 }
 275
 276 static ssize_t
 277 sd_show_protection_mode(struct device *dev, struct device_attribute *attr,
 278                         char *buf)
 279 {
 280         struct scsi_disk *sdkp = to_scsi_disk(dev);
 281         struct scsi_device *sdp = sdkp->device;
 282         unsigned int dif, dix;
 283
 284         dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
 285         dix = scsi_host_dix_capable(sdp->host, sdkp->protection_type);
 286
 287         if (!dix && scsi_host_dix_capable(sdp->host, SD_DIF_TYPE0_PROTECTION)) {
 288                 dif = 0;
 289                 dix = 1;
 290         }
 291
 292         if (!dif && !dix)
 293                 return snprintf(buf, 20, "none\n");
 294
 295         return snprintf(buf, 20, "%s%u\n", dix ? "dix" : "dif", dif);
 296 }
 297
 298 static ssize_t
 299 sd_show_app_tag_own(struct device *dev, struct device_attribute *attr,
 300                     char *buf)
 301 {
 302         struct scsi_disk *sdkp = to_scsi_disk(dev);
 303
 304         return snprintf(buf, 20, "%u\n", sdkp->ATO);
 305 }
 306
 307 static ssize_t
 308 sd_show_thin_provisioning(struct device *dev, struct device_attribute *attr,
 309                           char *buf)
 310 {
 311         struct scsi_disk *sdkp = to_scsi_disk(dev);
 312
 313         return snprintf(buf, 20, "%u\n", sdkp->lbpme);
 314 }
 315
 316 static const char *lbp_mode[] = {
 317         [SD_LBP_FULL]           = "full",
 318         [SD_LBP_UNMAP]          = "unmap",
 319         [SD_LBP_WS16]           = "writesame_16",
 320         [SD_LBP_WS10]           = "writesame_10",
 321         [SD_LBP_ZERO]           = "writesame_zero",
 322         [SD_LBP_DISABLE]        = "disabled",
 323 };
 324
 325 static ssize_t
 326 sd_show_provisioning_mode(struct device *dev, struct device_attribute *attr,
 327                           char *buf)
 328 {
 329         struct scsi_disk *sdkp = to_scsi_disk(dev);
 330
 331         return snprintf(buf, 20, "%s\n", lbp_mode[sdkp->provisioning_mode]);
 332 }
 333
 334 static ssize_t
 335 sd_store_provisioning_mode(struct device *dev, struct device_attribute *attr,
 336                            const char *buf, size_t count)
 337 {
 338         struct scsi_disk *sdkp = to_scsi_disk(dev);
 339         struct scsi_device *sdp = sdkp->device;
 340
 341         if (!capable(CAP_SYS_ADMIN))
 342                 return -EACCES;
 343
 344         if (sdp->type != TYPE_DISK)
 345                 return -EINVAL;
 346
 347         if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
 348                 sd_config_discard(sdkp, SD_LBP_UNMAP);
 349         else if (!strncmp(buf, lbp_mode[SD_LBP_WS16], 20))
 350                 sd_config_discard(sdkp, SD_LBP_WS16);
 351         else if (!strncmp(buf, lbp_mode[SD_LBP_WS10], 20))
 352                 sd_config_discard(sdkp, SD_LBP_WS10);
 353         else if (!strncmp(buf, lbp_mode[SD_LBP_ZERO], 20))
 354                 sd_config_discard(sdkp, SD_LBP_ZERO);
 355         else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20))
 356                 sd_config_discard(sdkp, SD_LBP_DISABLE);
 357         else
 358                 return -EINVAL;
 359
 360         return count;
 361 }
 362
 363 static struct device_attribute sd_disk_attrs[] = {
 364         __ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
 365                sd_store_cache_type),
 366         __ATTR(FUA, S_IRUGO, sd_show_fua, NULL),
 367         __ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart,
 368                sd_store_allow_restart),
 369         __ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
 370                sd_store_manage_start_stop),
 371         __ATTR(protection_type, S_IRUGO, sd_show_protection_type, NULL),
 372         __ATTR(protection_mode, S_IRUGO, sd_show_protection_mode, NULL),
 373         __ATTR(app_tag_own, S_IRUGO, sd_show_app_tag_own, NULL),
 374         __ATTR(thin_provisioning, S_IRUGO, sd_show_thin_provisioning, NULL),
 375         __ATTR(provisioning_mode, S_IRUGO|S_IWUSR, sd_show_provisioning_mode,
 376                sd_store_provisioning_mode),
 377         __ATTR_NULL,
 378 };
 379
 380 static struct class sd_disk_class = {
 381         .name           = "scsi_disk",
 382         .owner          = THIS_MODULE,
 383         .dev_release    = scsi_disk_release,
 384         .dev_attrs      = sd_disk_attrs,
 385 };
 386
 387 static struct scsi_driver sd_template = {
 388         .owner                  = THIS_MODULE,
 389         .gendrv = {
 390                 .name           = "sd",
 391                 .probe          = sd_probe,
 392                 .remove         = sd_remove,
 393                 .suspend        = sd_suspend,
 394                 .resume         = sd_resume,
 395                 .shutdown       = sd_shutdown,
 396         },
 397         .rescan                 = sd_rescan,
 398         .done                   = sd_done,
 399 };
 400
 401 /*
 402  * Device no to disk mapping:
 403  *
 404  *       major         disc2     disc  p1
 405  *   |............|.............|....|....| <- dev_t
 406  *    31        20 19          8 7  4 3  0
 407  *
 408  * Inside a major, we have 16k disks, however mapped non-
 409  * contiguously. The first 16 disks are for major0, the next
 410  * ones with major1, ... Disk 256 is for major0 again, disk 272
 411  * for major1, ...
 412  * As we stay compatible with our numbering scheme, we can reuse
 413  * the well-know SCSI majors 8, 65--71, 136--143.
 414  */
 415 static int sd_major(int major_idx)
 416 {
 417         switch (major_idx) {
 418         case 0:
 419                 return SCSI_DISK0_MAJOR;
 420         case 1 ... 7:
 421                 return SCSI_DISK1_MAJOR + major_idx - 1;
 422         case 8 ... 15:
 423                 return SCSI_DISK8_MAJOR + major_idx - 8;
 424         default:
 425                 BUG();
 426                 return 0;       /* shut up gcc */
 427         }
 428 }
 429
 430 static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
 431 {
 432         struct scsi_disk *sdkp = NULL;
 433
 434         if (disk->private_data) {
 435                 sdkp = scsi_disk(disk);
 436                 if (scsi_device_get(sdkp->device) == 0)
 437                         get_device(&sdkp->dev);
 438                 else
 439                         sdkp = NULL;
 440         }
 441         return sdkp;
 442 }
 443
 444 static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
 445 {
 446         struct scsi_disk *sdkp;
 447
 448         mutex_lock(&sd_ref_mutex);
 449         sdkp = __scsi_disk_get(disk);
 450         mutex_unlock(&sd_ref_mutex);
 451         return sdkp;
 452 }
 453
 454 static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
 455 {
 456         struct scsi_disk *sdkp;
 457
 458         mutex_lock(&sd_ref_mutex);
 459         sdkp = dev_get_drvdata(dev);
 460         if (sdkp)
 461                 sdkp = __scsi_disk_get(sdkp->disk);
 462         mutex_unlock(&sd_ref_mutex);
 463         return sdkp;
 464 }
 465
 466 static void scsi_disk_put(struct scsi_disk *sdkp)
 467 {
 468         struct scsi_device *sdev = sdkp->device;
 469
 470         mutex_lock(&sd_ref_mutex);
 471         put_device(&sdkp->dev);
 472         scsi_device_put(sdev);
 473         mutex_unlock(&sd_ref_mutex);
 474 }
 475
 476 static void sd_prot_op(struct scsi_cmnd *scmd, unsigned int dif)
 477 {
 478         unsigned int prot_op = SCSI_PROT_NORMAL;
 479         unsigned int dix = scsi_prot_sg_count(scmd);
 480
 481         if (scmd->sc_data_direction == DMA_FROM_DEVICE) {
 482                 if (dif && dix)
 483                         prot_op = SCSI_PROT_READ_PASS;
 484                 else if (dif && !dix)
 485                         prot_op = SCSI_PROT_READ_STRIP;
 486                 else if (!dif && dix)
 487                         prot_op = SCSI_PROT_READ_INSERT;
 488         } else {
 489                 if (dif && dix)
 490                         prot_op = SCSI_PROT_WRITE_PASS;
 491                 else if (dif && !dix)
 492                         prot_op = SCSI_PROT_WRITE_INSERT;
 493                 else if (!dif && dix)
 494                         prot_op = SCSI_PROT_WRITE_STRIP;
 495         }
 496
 497         scsi_set_prot_op(scmd, prot_op);
 498         scsi_set_prot_type(scmd, dif);
 499 }
 500
 501 static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
 502 {
 503         struct request_queue *q = sdkp->disk->queue;
 504         unsigned int logical_block_size = sdkp->device->sector_size;
 505         unsigned int max_blocks = 0;
 506
 507         q->limits.discard_zeroes_data = sdkp->lbprz;
 508         q->limits.discard_alignment = sdkp->unmap_alignment *
 509                 logical_block_size;
 510         q->limits.discard_granularity =
 511                 max(sdkp->physical_block_size,
 512                     sdkp->unmap_granularity * logical_block_size);
 513
 514         switch (mode) {
 515
 516         case SD_LBP_DISABLE:
 517                 q->limits.max_discard_sectors = 0;
 518                 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
 519                 return;
 520
 521         case SD_LBP_UNMAP:
 522                 max_blocks = min_not_zero(sdkp->max_unmap_blocks, 0xffffffff);
 523                 break;
 524
 525         case SD_LBP_WS16:
 526                 max_blocks = min_not_zero(sdkp->max_ws_blocks, 0xffffffff);
 527                 break;
 528
 529         case SD_LBP_WS10:
 530                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
 531                 break;
 532
 533         case SD_LBP_ZERO:
 534                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
 535                 q->limits.discard_zeroes_data = 1;
 536                 break;
 537         }
 538
 539         q->limits.max_discard_sectors = max_blocks * (logical_block_size >> 9);
 540         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
 541
 542         sdkp->provisioning_mode = mode;
 543 }
 544
 545 /**
 546  * scsi_setup_discard_cmnd - unmap blocks on thinly provisioned device
 547  * @sdp: scsi device to operate one
 548  * @rq: Request to prepare
 549  *
 550  * Will issue either UNMAP or WRITE SAME(16) depending on preference
 551  * indicated by target device.
 552  **/
 553 static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
 554 {
 555         struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
 556         struct bio *bio = rq->bio;
 557         sector_t sector = bio->bi_sector;
 558         unsigned int nr_sectors = bio_sectors(bio);
 559         unsigned int len;
 560         int ret;
 561         char *buf;
 562         struct page *page;
 563
 564         if (sdkp->device->sector_size == 4096) {
 565                 sector >>= 3;
 566                 nr_sectors >>= 3;
 567         }
 568
 569         rq->timeout = SD_TIMEOUT;
 570
 571         memset(rq->cmd, 0, rq->cmd_len);
 572
 573         page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
 574         if (!page)
 575                 return BLKPREP_DEFER;
 576
 577         switch (sdkp->provisioning_mode) {
 578         case SD_LBP_UNMAP:
 579                 buf = page_address(page);
 580
 581                 rq->cmd_len = 10;
 582                 rq->cmd[0] = UNMAP;
 583                 rq->cmd[8] = 24;
 584
 585                 put_unaligned_be16(6 + 16, &buf[0]);
 586                 put_unaligned_be16(16, &buf[2]);
 587                 put_unaligned_be64(sector, &buf[8]);
 588                 put_unaligned_be32(nr_sectors, &buf[16]);
 589
 590                 len = 24;
 591                 break;
 592
 593         case SD_LBP_WS16:
 594                 rq->cmd_len = 16;
 595                 rq->cmd[0] = WRITE_SAME_16;
 596                 rq->cmd[1] = 0x8; /* UNMAP */
 597                 put_unaligned_be64(sector, &rq->cmd[2]);
 598                 put_unaligned_be32(nr_sectors, &rq->cmd[10]);
 599
 600                 len = sdkp->device->sector_size;
 601                 break;
 602
 603         case SD_LBP_WS10:
 604         case SD_LBP_ZERO:
 605                 rq->cmd_len = 10;
 606                 rq->cmd[0] = WRITE_SAME;
 607                 if (sdkp->provisioning_mode == SD_LBP_WS10)
 608                         rq->cmd[1] = 0x8; /* UNMAP */
 609                 put_unaligned_be32(sector, &rq->cmd[2]);
 610                 put_unaligned_be16(nr_sectors, &rq->cmd[7]);
 611
 612                 len = sdkp->device->sector_size;
 613                 break;
 614
 615         default:
 616                 ret = BLKPREP_KILL;
 617                 goto out;
 618         }
 619
 620         blk_add_request_payload(rq, page, len);
 621         ret = scsi_setup_blk_pc_cmnd(sdp, rq);
 622         rq->buffer = page_address(page);
 623
 624 out:
 625         if (ret != BLKPREP_OK) {
 626                 __free_page(page);
 627                 rq->buffer = NULL;
 628         }
 629         return ret;
 630 }
 631
 632 static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq)
 633 {
 634         rq->timeout = SD_FLUSH_TIMEOUT;
 635         rq->retries = SD_MAX_RETRIES;
 636         rq->cmd[0] = SYNCHRONIZE_CACHE;
 637         rq->cmd_len = 10;
 638
 639         return scsi_setup_blk_pc_cmnd(sdp, rq);
 640 }
 641
 642 static void sd_unprep_fn(struct request_queue *q, struct request *rq)
 643 {
 644         if (rq->cmd_flags & REQ_DISCARD) {
 645                 free_page((unsigned long)rq->buffer);
 646                 rq->buffer = NULL;
 647         }
 648 }
 649
 650 /**
 651  *      sd_init_command - build a scsi (read or write) command from
 652  *      information in the request structure.
 653  *      @SCpnt: pointer to mid-level's per scsi command structure that
 654  *      contains request and into which the scsi command is written
 655  *
 656  *      Returns 1 if successful and 0 if error (or cannot be done now).
 657  **/
 658 static int sd_prep_fn(struct request_queue *q, struct request *rq)
 659 {
 660         struct scsi_cmnd *SCpnt;
 661         struct scsi_device *sdp = q->queuedata;
 662         struct gendisk *disk = rq->rq_disk;
 663         struct scsi_disk *sdkp;
 664         sector_t block = blk_rq_pos(rq);
 665         sector_t threshold;
 666         unsigned int this_count = blk_rq_sectors(rq);
 667         int ret, host_dif;
 668         unsigned char protect;
 669
 670         /*
 671          * Discard request come in as REQ_TYPE_FS but we turn them into
 672          * block PC requests to make life easier.
 673          */
 674         if (rq->cmd_flags & REQ_DISCARD) {
 675                 ret = scsi_setup_discard_cmnd(sdp, rq);
 676                 goto out;
 677         } else if (rq->cmd_flags & REQ_FLUSH) {
 678                 ret = scsi_setup_flush_cmnd(sdp, rq);
 679                 goto out;
 680         } else if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
 681                 ret = scsi_setup_blk_pc_cmnd(sdp, rq);
 682                 goto out;
 683         } else if (rq->cmd_type != REQ_TYPE_FS) {
 684                 ret = BLKPREP_KILL;
 685                 goto out;
 686         }
 687         ret = scsi_setup_fs_cmnd(sdp, rq);
 688         if (ret != BLKPREP_OK)
 689                 goto out;
 690         SCpnt = rq->special;
 691         sdkp = scsi_disk(disk);
 692
 693         /* from here on until we're complete, any goto out
 694          * is used for a killable error condition */
 695         ret = BLKPREP_KILL;
 696
 697         SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
 698                                         "sd_init_command: block=%llu, "
 699                                         "count=%d\n",
 700                                         (unsigned long long)block,
 701                                         this_count));
 702
 703         if (!sdp || !scsi_device_online(sdp) ||
 704             block + blk_rq_sectors(rq) > get_capacity(disk)) {
 705                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 706                                                 "Finishing %u sectors\n",
 707                                                 blk_rq_sectors(rq)));
 708                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 709                                                 "Retry with 0x%p\n", SCpnt));
 710                 goto out;
 711         }
 712
 713         if (sdp->changed) {
 714                 /*
 715                  * quietly refuse to do anything to a changed disc until
 716                  * the changed bit has been reset
 717                  */
 718                 /* printk("SCSI disk has been changed or is not present. Prohibiting further I/O.\n"); */
 719                 goto out;
 720         }
 721
 722         /*
 723          * Some SD card readers can't handle multi-sector accesses which touch
 724          * the last one or two hardware sectors.  Split accesses as needed.
 725          */
 726         threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
 727                 (sdp->sector_size / 512);
 728
 729         if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
 730                 if (block < threshold) {
 731                         /* Access up to the threshold but not beyond */
 732                         this_count = threshold - block;
 733                 } else {
 734                         /* Access only a single hardware sector */
 735                         this_count = sdp->sector_size / 512;
 736                 }
 737         }
 738
 739         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
 740                                         (unsigned long long)block));
 741
 742         /*
 743          * If we have a 1K hardware sectorsize, prevent access to single
 744          * 512 byte sectors.  In theory we could handle this - in fact
 745          * the scsi cdrom driver must be able to handle this because
 746          * we typically use 1K blocksizes, and cdroms typically have
 747          * 2K hardware sectorsizes.  Of course, things are simpler
 748          * with the cdrom, since it is read-only.  For performance
 749          * reasons, the filesystems should be able to handle this
 750          * and not force the scsi disk driver to use bounce buffers
 751          * for this.
 752          */
 753         if (sdp->sector_size == 1024) {
 754                 if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
 755                         scmd_printk(KERN_ERR, SCpnt,
 756                                     "Bad block number requested\n");
 757                         goto out;
 758                 } else {
 759                         block = block >> 1;
 760                         this_count = this_count >> 1;
 761                 }
 762         }
 763         if (sdp->sector_size == 2048) {
 764                 if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
 765                         scmd_printk(KERN_ERR, SCpnt,
 766                                     "Bad block number requested\n");
 767                         goto out;
 768                 } else {
 769                         block = block >> 2;
 770                         this_count = this_count >> 2;
 771                 }
 772         }
 773         if (sdp->sector_size == 4096) {
 774                 if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
 775                         scmd_printk(KERN_ERR, SCpnt,
 776                                     "Bad block number requested\n");
 777                         goto out;
 778                 } else {
 779                         block = block >> 3;
 780                         this_count = this_count >> 3;
 781                 }
 782         }
 783         if (rq_data_dir(rq) == WRITE) {
 784                 if (!sdp->writeable) {
 785                         goto out;
 786                 }
 787                 SCpnt->cmnd[0] = WRITE_6;
 788                 SCpnt->sc_data_direction = DMA_TO_DEVICE;
 789
 790                 if (blk_integrity_rq(rq) &&
 791                     sd_dif_prepare(rq, block, sdp->sector_size) == -EIO)
 792                         goto out;
 793
 794         } else if (rq_data_dir(rq) == READ) {
 795                 SCpnt->cmnd[0] = READ_6;
 796                 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
 797         } else {
 798                 scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
 799                 goto out;
 800         }
 801
 802         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
 803                                         "%s %d/%u 512 byte blocks.\n",
 804                                         (rq_data_dir(rq) == WRITE) ?
 805                                         "writing" : "reading", this_count,
 806                                         blk_rq_sectors(rq)));
 807
 808         /* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
 809         host_dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
 810         if (host_dif)
 811                 protect = 1 << 5;
 812         else
 813                 protect = 0;
 814
 815         if (host_dif == SD_DIF_TYPE2_PROTECTION) {
 816                 SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
 817
 818                 if (unlikely(SCpnt->cmnd == NULL)) {
 819                         ret = BLKPREP_DEFER;
 820                         goto out;
 821                 }
 822
 823                 SCpnt->cmd_len = SD_EXT_CDB_SIZE;
 824                 memset(SCpnt->cmnd, 0, SCpnt->cmd_len);
 825                 SCpnt->cmnd[0] = VARIABLE_LENGTH_CMD;
 826                 SCpnt->cmnd[7] = 0x18;
 827                 SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
 828                 SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
 829
 830                 /* LBA */
 831                 SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
 832                 SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
 833                 SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
 834                 SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
 835                 SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
 836                 SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
 837                 SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
 838                 SCpnt->cmnd[19] = (unsigned char) block & 0xff;
 839
 840                 /* Expected Indirect LBA */
 841                 SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
 842                 SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
 843                 SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
 844                 SCpnt->cmnd[23] = (unsigned char) block & 0xff;
 845
 846                 /* Transfer length */
 847                 SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
 848                 SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
 849                 SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
 850                 SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
 851         } else if (block > 0xffffffff) {
 852                 SCpnt->cmnd[0] += READ_16 - READ_6;
 853                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
 854                 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
 855                 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
 856                 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
 857                 SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
 858                 SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
 859                 SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
 860                 SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
 861                 SCpnt->cmnd[9] = (unsigned char) block & 0xff;
 862                 SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
 863                 SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
 864                 SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
 865                 SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
 866                 SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
 867         } else if ((this_count > 0xff) || (block > 0x1fffff) ||
 868                    scsi_device_protection(SCpnt->device) ||
 869                    SCpnt->device->use_10_for_rw) {
 870                 if (this_count > 0xffff)
 871                         this_count = 0xffff;
 872
 873                 SCpnt->cmnd[0] += READ_10 - READ_6;
 874                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
 875                 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
 876                 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
 877                 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
 878                 SCpnt->cmnd[5] = (unsigned char) block & 0xff;
 879                 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
 880                 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
 881                 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
 882         } else {
 883                 if (unlikely(rq->cmd_flags & REQ_FUA)) {
 884                         /*
 885                          * This happens only if this drive failed
 886                          * 10byte rw command with ILLEGAL_REQUEST
 887                          * during operation and thus turned off
 888                          * use_10_for_rw.
 889                          */
 890                         scmd_printk(KERN_ERR, SCpnt,
 891                                     "FUA write on READ/WRITE(6) drive\n");
 892                         goto out;
 893                 }
 894
 895                 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
 896                 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
 897                 SCpnt->cmnd[3] = (unsigned char) block & 0xff;
 898                 SCpnt->cmnd[4] = (unsigned char) this_count;
 899                 SCpnt->cmnd[5] = 0;
 900         }
 901         SCpnt->sdb.length = this_count * sdp->sector_size;
 902
 903         /* If DIF or DIX is enabled, tell HBA how to handle request */
 904         if (host_dif || scsi_prot_sg_count(SCpnt))
 905                 sd_prot_op(SCpnt, host_dif);
 906
 907         /*
 908          * We shouldn't disconnect in the middle of a sector, so with a dumb
 909          * host adapter, it's safe to assume that we can at least transfer
 910          * this many bytes between each connect / disconnect.
 911          */
 912         SCpnt->transfersize = sdp->sector_size;
 913         SCpnt->underflow = this_count << 9;
 914         SCpnt->allowed = SD_MAX_RETRIES;
 915
 916         /*
 917          * This indicates that the command is ready from our end to be
 918          * queued.
 919          */
 920         ret = BLKPREP_OK;
 921  out:
 922         return scsi_prep_return(q, rq, ret);
 923 }
 924
 925 /**
 926  *      sd_open - open a scsi disk device
 927  *      @inode: only i_rdev member may be used
 928  *      @filp: only f_mode and f_flags may be used
 929  *
 930  *      Returns 0 if successful. Returns a negated errno value in case
 931  *      of error.
 932  *
 933  *      Note: This can be called from a user context (e.g. fsck(1) )
 934  *      or from within the kernel (e.g. as a result of a mount(1) ).
 935  *      In the latter case @inode and @filp carry an abridged amount
 936  *      of information as noted above.
 937  *
 938  *      Locking: called with bdev->bd_mutex held.
 939  **/
 940 static int sd_open(struct block_device *bdev, fmode_t mode)
 941 {
 942         struct scsi_disk *sdkp = scsi_disk_get(bdev->bd_disk);
 943         struct scsi_device *sdev;
 944         int retval;
 945
 946         if (!sdkp)
 947                 return -ENXIO;
 948
 949         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
 950
 951         sdev = sdkp->device;
 952
 953         retval = scsi_autopm_get_device(sdev);
 954         if (retval)
 955                 goto error_autopm;
 956
 957         /*
 958          * If the device is in error recovery, wait until it is done.
 959          * If the device is offline, then disallow any access to it.
 960          */
 961         retval = -ENXIO;
 962         if (!scsi_block_when_processing_errors(sdev))
 963                 goto error_out;
 964
 965         if (sdev->removable || sdkp->write_prot)
 966                 check_disk_change(bdev);
 967
 968         /*
 969          * If the drive is empty, just let the open fail.
 970          */
 971         retval = -ENOMEDIUM;
 972         if (sdev->removable && !sdkp->media_present && !(mode & FMODE_NDELAY))
 973                 goto error_out;
 974
 975         /*
 976          * If the device has the write protect tab set, have the open fail
 977          * if the user expects to be able to write to the thing.
 978          */
 979         retval = -EROFS;
 980         if (sdkp->write_prot && (mode & FMODE_WRITE))
 981                 goto error_out;
 982
 983         /*
 984          * It is possible that the disk changing stuff resulted in
 985          * the device being taken offline.  If this is the case,
 986          * report this to the user, and don't pretend that the
 987          * open actually succeeded.
 988          */
 989         retval = -ENXIO;
 990         if (!scsi_device_online(sdev))
 991                 goto error_out;
 992
 993         if ((atomic_inc_return(&sdkp->openers) == 1) && sdev->removable) {
 994                 if (scsi_block_when_processing_errors(sdev))
 995                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
 996         }
 997
 998         return 0;
 999
1000 error_out:
1001         scsi_autopm_put_device(sdev);
1002 error_autopm:
1003         scsi_disk_put(sdkp);
1004         return retval;
1005 }
1006
1007 /**
1008  *      sd_release - invoked when the (last) close(2) is called on this
1009  *      scsi disk.
1010  *      @inode: only i_rdev member may be used
1011  *      @filp: only f_mode and f_flags may be used
1012  *
1013  *      Returns 0.
1014  *
1015  *      Note: may block (uninterruptible) if error recovery is underway
1016  *      on this disk.
1017  *
1018  *      Locking: called with bdev->bd_mutex held.
1019  **/
1020 static int sd_release(struct gendisk *disk, fmode_t mode)
1021 {
1022         struct scsi_disk *sdkp = scsi_disk(disk);
1023         struct scsi_device *sdev = sdkp->device;
1024
1025         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
1026
1027         if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
1028                 if (scsi_block_when_processing_errors(sdev))
1029                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
1030         }
1031
1032         /*
1033          * XXX and what if there are packets in flight and this close()
1034          * XXX is followed by a "rmmod sd_mod"?
1035          */
1036
1037         scsi_autopm_put_device(sdev);
1038         scsi_disk_put(sdkp);
1039         return 0;
1040 }
1041
1042 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1043 {
1044         struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
1045         struct scsi_device *sdp = sdkp->device;
1046         struct Scsi_Host *host = sdp->host;
1047         int diskinfo[4];
1048
1049         /* default to most commonly used values */
1050         diskinfo[0] = 0x40;     /* 1 << 6 */
1051         diskinfo[1] = 0x20;     /* 1 << 5 */
1052         diskinfo[2] = sdkp->capacity >> 11;
1053
1054         /* override with calculated, extended default, or driver values */
1055         if (host->hostt->bios_param)
1056                 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
1057         else
1058                 scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
1059
1060         geo->heads = diskinfo[0];
1061         geo->sectors = diskinfo[1];
1062         geo->cylinders = diskinfo[2];
1063         return 0;
1064 }
1065
1066 /**
1067  *      sd_ioctl - process an ioctl
1068  *      @inode: only i_rdev/i_bdev members may be used
1069  *      @filp: only f_mode and f_flags may be used
1070  *      @cmd: ioctl command number
1071  *      @arg: this is third argument given to ioctl(2) system call.
1072  *      Often contains a pointer.
1073  *
1074  *      Returns 0 if successful (some ioctls return positive numbers on
1075  *      success as well). Returns a negated errno value in case of error.
1076  *
1077  *      Note: most ioctls are forward onto the block subsystem or further
1078  *      down in the scsi subsystem.
1079  **/
1080 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
1081                     unsigned int cmd, unsigned long arg)
1082 {
1083         struct gendisk *disk = bdev->bd_disk;
1084         struct scsi_disk *sdkp = scsi_disk(disk);
1085         struct scsi_device *sdp = sdkp->device;
1086         void __user *p = (void __user *)arg;
1087         int error;
1088
1089         SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
1090                                     "cmd=0x%x\n", disk->disk_name, cmd));
1091
1092         error = scsi_verify_blk_ioctl(bdev, cmd);
1093         if (error < 0)
1094                 return error;
1095
1096         /*
1097          * If we are in the middle of error recovery, don't let anyone
1098          * else try and use this device.  Also, if error recovery fails, it
1099          * may try and take the device offline, in which case all further
1100          * access to the device is prohibited.
1101          */
1102         error = scsi_nonblockable_ioctl(sdp, cmd, p,
1103                                         (mode & FMODE_NDELAY) != 0);
1104         if (!scsi_block_when_processing_errors(sdp) || !error)
1105                 goto out;
1106
1107         /*
1108          * Send SCSI addressing ioctls directly to mid level, send other
1109          * ioctls to block level and then onto mid level if they can't be
1110          * resolved.
1111          */
1112         switch (cmd) {
1113                 case SCSI_IOCTL_GET_IDLUN:
1114                 case SCSI_IOCTL_GET_BUS_NUMBER:
1115                         error = scsi_ioctl(sdp, cmd, p);
1116                         break;
1117                 default:
1118                         error = scsi_cmd_blk_ioctl(bdev, mode, cmd, p);
1119                         if (error != -ENOTTY)
1120                                 break;
1121                         error = scsi_ioctl(sdp, cmd, p);
1122                         break;
1123         }
1124 out:
1125         return error;
1126 }
1127
1128 static void set_media_not_present(struct scsi_disk *sdkp)
1129 {
1130         if (sdkp->media_present)
1131                 sdkp->device->changed = 1;
1132
1133         if (sdkp->device->removable) {
1134                 sdkp->media_present = 0;
1135                 sdkp->capacity = 0;
1136         }
1137 }
1138
1139 static int media_not_present(struct scsi_disk *sdkp,
1140                              struct scsi_sense_hdr *sshdr)
1141 {
1142         if (!scsi_sense_valid(sshdr))
1143                 return 0;
1144
1145         /* not invoked for commands that could return deferred errors */
1146         switch (sshdr->sense_key) {
1147         case UNIT_ATTENTION:
1148         case NOT_READY:
1149                 /* medium not present */
1150                 if (sshdr->asc == 0x3A) {
1151                         set_media_not_present(sdkp);
1152                         return 1;
1153                 }
1154         }
1155         return 0;
1156 }
1157
1158 /**
1159  *      sd_check_events - check media events
1160  *      @disk: kernel device descriptor
1161  *      @clearing: disk events currently being cleared
1162  *
1163  *      Returns mask of DISK_EVENT_*.
1164  *
1165  *      Note: this function is invoked from the block subsystem.
1166  **/
1167 static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
1168 {
1169         struct scsi_disk *sdkp = scsi_disk(disk);
1170         struct scsi_device *sdp = sdkp->device;
1171         struct scsi_sense_hdr *sshdr = NULL;
1172         int retval;
1173
1174         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
1175
1176         /*
1177          * If the device is offline, don't send any commands - just pretend as
1178          * if the command failed.  If the device ever comes back online, we
1179          * can deal with it then.  It is only because of unrecoverable errors
1180          * that we would ever take a device offline in the first place.
1181          */
1182         if (!scsi_device_online(sdp)) {
1183                 set_media_not_present(sdkp);
1184                 goto out;
1185         }
1186
1187         /*
1188          * Using TEST_UNIT_READY enables differentiation between drive with
1189          * no cartridge loaded - NOT READY, drive with changed cartridge -
1190          * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
1191          *
1192          * Drives that auto spin down. eg iomega jaz 1G, will be started
1193          * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
1194          * sd_revalidate() is called.
1195          */
1196         retval = -ENODEV;
1197
1198         if (scsi_block_when_processing_errors(sdp)) {
1199                 sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
1200                 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
1201                                               sshdr);
1202         }
1203
1204         /* failed to execute TUR, assume media not present */
1205         if (host_byte(retval)) {
1206                 set_media_not_present(sdkp);
1207                 goto out;
1208         }
1209
1210         if (media_not_present(sdkp, sshdr))
1211                 goto out;
1212
1213         /*
1214          * For removable scsi disk we have to recognise the presence
1215          * of a disk in the drive.
1216          */
1217         if (!sdkp->media_present)
1218                 sdp->changed = 1;
1219         sdkp->media_present = 1;
1220 out:
1221         /*
1222          * sdp->changed is set under the following conditions:
1223          *
1224          *      Medium present state has changed in either direction.
1225          *      Device has indicated UNIT_ATTENTION.
1226          */
1227         kfree(sshdr);
1228         retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
1229         sdp->changed = 0;
1230         return retval;
1231 }
1232
1233 static int sd_sync_cache(struct scsi_disk *sdkp)
1234 {
1235         int retries, res;
1236         struct scsi_device *sdp = sdkp->device;
1237         struct scsi_sense_hdr sshdr;
1238
1239         if (!scsi_device_online(sdp))
1240                 return -ENODEV;
1241
1242
1243         for (retries = 3; retries > 0; --retries) {
1244                 unsigned char cmd[10] = { 0 };
1245
1246                 cmd[0] = SYNCHRONIZE_CACHE;
1247                 /*
1248                  * Leave the rest of the command zero to indicate
1249                  * flush everything.
1250                  */
1251                 res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
1252                                        SD_FLUSH_TIMEOUT, SD_MAX_RETRIES, NULL);
1253                 if (res == 0)
1254                         break;
1255         }
1256
1257         if (res) {
1258                 sd_print_result(sdkp, res);
1259                 if (driver_byte(res) & DRIVER_SENSE)
1260                         sd_print_sense_hdr(sdkp, &sshdr);
1261         }
1262
1263         if (res)
1264                 return -EIO;
1265         return 0;
1266 }
1267
1268 static void sd_rescan(struct device *dev)
1269 {
1270         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
1271
1272         if (sdkp) {
1273                 revalidate_disk(sdkp->disk);
1274                 scsi_disk_put(sdkp);
1275         }
1276 }
1277
1278
1279 #ifdef CONFIG_COMPAT
1280 /*
1281  * This gets directly called from VFS. When the ioctl
1282  * is not recognized we go back to the other translation paths.
1283  */
1284 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
1285                            unsigned int cmd, unsigned long arg)
1286 {
1287         struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1288         int ret;
1289
1290         ret = scsi_verify_blk_ioctl(bdev, cmd);
1291         if (ret < 0)
1292                 return -ENOIOCTLCMD;
1293
1294         /*
1295          * If we are in the middle of error recovery, don't let anyone
1296          * else try and use this device.  Also, if error recovery fails, it
1297          * may try and take the device offline, in which case all further
1298          * access to the device is prohibited.
1299          */
1300         if (!scsi_block_when_processing_errors(sdev))
1301                 return -ENODEV;
1302
1303         if (sdev->host->hostt->compat_ioctl) {
1304                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
1305
1306                 return ret;
1307         }
1308
1309         /*
1310          * Let the static ioctl translation table take care of it.
1311          */
1312         return -ENOIOCTLCMD;
1313 }
1314 #endif
1315
1316 static const struct block_device_operations sd_fops = {
1317         .owner                  = THIS_MODULE,
1318         .open                   = sd_open,
1319         .release                = sd_release,
1320         .ioctl                  = sd_ioctl,
1321         .getgeo                 = sd_getgeo,
1322 #ifdef CONFIG_COMPAT
1323         .compat_ioctl           = sd_compat_ioctl,
1324 #endif
1325         .check_events           = sd_check_events,
1326         .revalidate_disk        = sd_revalidate_disk,
1327         .unlock_native_capacity = sd_unlock_native_capacity,
1328 };
1329
1330 static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
1331 {
1332         u64 start_lba = blk_rq_pos(scmd->request);
1333         u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
1334         u64 bad_lba;
1335         int info_valid;
1336         /*
1337          * resid is optional but mostly filled in.  When it's unused,
1338          * its value is zero, so we assume the whole buffer transferred
1339          */
1340         unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
1341         unsigned int good_bytes;
1342
1343         if (scmd->request->cmd_type != REQ_TYPE_FS)
1344                 return 0;
1345
1346         info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
1347                                              SCSI_SENSE_BUFFERSIZE,
1348                                              &bad_lba);
1349         if (!info_valid)
1350                 return 0;
1351
1352         if (scsi_bufflen(scmd) <= scmd->device->sector_size)
1353                 return 0;
1354
1355         if (scmd->device->sector_size < 512) {
1356                 /* only legitimate sector_size here is 256 */
1357                 start_lba <<= 1;
1358                 end_lba <<= 1;
1359         } else {
1360                 /* be careful ... don't want any overflows */
1361                 u64 factor = scmd->device->sector_size / 512;
1362                 do_div(start_lba, factor);
1363                 do_div(end_lba, factor);
1364         }
1365
1366         /* The bad lba was reported incorrectly, we have no idea where
1367          * the error is.
1368          */
1369         if (bad_lba < start_lba  || bad_lba >= end_lba)
1370                 return 0;
1371
1372         /* This computation should always be done in terms of
1373          * the resolution of the device's medium.
1374          */
1375         good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
1376         return min(good_bytes, transferred);
1377 }
1378
1379 /**
1380  *      sd_done - bottom half handler: called when the lower level
1381  *      driver has completed (successfully or otherwise) a scsi command.
1382  *      @SCpnt: mid-level's per command structure.
1383  *
1384  *      Note: potentially run from within an ISR. Must not block.
1385  **/
1386 static int sd_done(struct scsi_cmnd *SCpnt)
1387 {
1388         int result = SCpnt->result;
1389         unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
1390         struct scsi_sense_hdr sshdr;
1391         struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
1392         int sense_valid = 0;
1393         int sense_deferred = 0;
1394         unsigned char op = SCpnt->cmnd[0];
1395
1396         if ((SCpnt->request->cmd_flags & REQ_DISCARD) && !result)
1397                 scsi_set_resid(SCpnt, 0);
1398
1399         if (result) {
1400                 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
1401                 if (sense_valid)
1402                         sense_deferred = scsi_sense_is_deferred(&sshdr);
1403         }
1404 #ifdef CONFIG_SCSI_LOGGING
1405         SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
1406         if (sense_valid) {
1407                 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
1408                                                    "sd_done: sb[respc,sk,asc,"
1409                                                    "ascq]=%x,%x,%x,%x\n",
1410                                                    sshdr.response_code,
1411                                                    sshdr.sense_key, sshdr.asc,
1412                                                    sshdr.ascq));
1413         }
1414 #endif
1415         if (driver_byte(result) != DRIVER_SENSE &&
1416             (!sense_valid || sense_deferred))
1417                 goto out;
1418
1419         switch (sshdr.sense_key) {
1420         case HARDWARE_ERROR:
1421         case MEDIUM_ERROR:
1422                 good_bytes = sd_completed_bytes(SCpnt);
1423                 break;
1424         case RECOVERED_ERROR:
1425                 good_bytes = scsi_bufflen(SCpnt);
1426                 break;
1427         case NO_SENSE:
1428                 /* This indicates a false check condition, so ignore it.  An
1429                  * unknown amount of data was transferred so treat it as an
1430                  * error.
1431                  */
1432                 scsi_print_sense("sd", SCpnt);
1433                 SCpnt->result = 0;
1434                 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1435                 break;
1436         case ABORTED_COMMAND:
1437                 if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
1438                         good_bytes = sd_completed_bytes(SCpnt);
1439                 break;
1440         case ILLEGAL_REQUEST:
1441                 if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
1442                         good_bytes = sd_completed_bytes(SCpnt);
1443                 /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
1444                 if ((sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1445                     (op == UNMAP || op == WRITE_SAME_16 || op == WRITE_SAME))
1446                         sd_config_discard(sdkp, SD_LBP_DISABLE);
1447                 break;
1448         default:
1449                 break;
1450         }
1451  out:
1452         if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
1453                 sd_dif_complete(SCpnt, good_bytes);
1454
1455         if (scsi_host_dif_capable(sdkp->device->host, sdkp->protection_type)
1456             == SD_DIF_TYPE2_PROTECTION && SCpnt->cmnd != SCpnt->request->cmd) {
1457
1458                 /* We have to print a failed command here as the
1459                  * extended CDB gets freed before scsi_io_completion()
1460                  * is called.
1461                  */
1462                 if (result)
1463                         scsi_print_command(SCpnt);
1464
1465                 mempool_free(SCpnt->cmnd, sd_cdb_pool);
1466                 SCpnt->cmnd = NULL;
1467                 SCpnt->cmd_len = 0;
1468         }
1469
1470         return good_bytes;
1471 }
1472
1473 /*
1474  * spinup disk - called only in sd_revalidate_disk()
1475  */
1476 static void
1477 sd_spinup_disk(struct scsi_disk *sdkp)
1478 {
1479         unsigned char cmd[10];
1480         unsigned long spintime_expire = 0;
1481         int retries, spintime;
1482         unsigned int the_result;
1483         struct scsi_sense_hdr sshdr;
1484         int sense_valid = 0;
1485
1486         spintime = 0;
1487
1488         /* Spin up drives, as required.  Only do this at boot time */
1489         /* Spinup needs to be done for module loads too. */
1490         do {
1491                 retries = 0;
1492
1493                 do {
1494                         cmd[0] = TEST_UNIT_READY;
1495                         memset((void *) &cmd[1], 0, 9);
1496
1497                         the_result = scsi_execute_req(sdkp->device, cmd,
1498                                                       DMA_NONE, NULL, 0,
1499                                                       &sshdr, SD_TIMEOUT,
1500                                                       SD_MAX_RETRIES, NULL);
1501
1502                         /*
1503                          * If the drive has indicated to us that it
1504                          * doesn't have any media in it, don't bother
1505                          * with any more polling.
1506                          */
1507                         if (media_not_present(sdkp, &sshdr))
1508                                 return;
1509
1510                         if (the_result)
1511                                 sense_valid = scsi_sense_valid(&sshdr);
1512                         retries++;
1513                 } while (retries < 3 &&
1514                          (!scsi_status_is_good(the_result) ||
1515                           ((driver_byte(the_result) & DRIVER_SENSE) &&
1516                           sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1517
1518                 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1519                         /* no sense, TUR either succeeded or failed
1520                          * with a status error */
1521                         if(!spintime && !scsi_status_is_good(the_result)) {
1522                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1523                                 sd_print_result(sdkp, the_result);
1524                         }
1525                         break;
1526                 }
1527
1528                 /*
1529                  * The device does not want the automatic start to be issued.
1530                  */
1531                 if (sdkp->device->no_start_on_add)
1532                         break;
1533
1534                 if (sense_valid && sshdr.sense_key == NOT_READY) {
1535                         if (sshdr.asc == 4 && sshdr.ascq == 3)
1536                                 break;  /* manual intervention required */
1537                         if (sshdr.asc == 4 && sshdr.ascq == 0xb)
1538                                 break;  /* standby */
1539                         if (sshdr.asc == 4 && sshdr.ascq == 0xc)
1540                                 break;  /* unavailable */
1541                         /*
1542                          * Issue command to spin up drive when not ready
1543                          */
1544                         if (!spintime) {
1545                                 sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
1546                                 cmd[0] = START_STOP;
1547                                 cmd[1] = 1;     /* Return immediately */
1548                                 memset((void *) &cmd[2], 0, 8);
1549                                 cmd[4] = 1;     /* Start spin cycle */
1550                                 if (sdkp->device->start_stop_pwr_cond)
1551                                         cmd[4] |= 1 << 4;
1552                                 scsi_execute_req(sdkp->device, cmd, DMA_NONE,
1553                                                  NULL, 0, &sshdr,
1554                                                  SD_TIMEOUT, SD_MAX_RETRIES,
1555                                                  NULL);
1556                                 spintime_expire = jiffies + 100 * HZ;
1557                                 spintime = 1;
1558                         }
1559                         /* Wait 1 second for next try */
1560                         msleep(1000);
1561                         printk(".");
1562
1563                 /*
1564                  * Wait for USB flash devices with slow firmware.
1565                  * Yes, this sense key/ASC combination shouldn't
1566                  * occur here.  It's characteristic of these devices.
1567                  */
1568                 } else if (sense_valid &&
1569                                 sshdr.sense_key == UNIT_ATTENTION &&
1570                                 sshdr.asc == 0x28) {
1571                         if (!spintime) {
1572                                 spintime_expire = jiffies + 5 * HZ;
1573                                 spintime = 1;
1574                         }
1575                         /* Wait 1 second for next try */
1576                         msleep(1000);
1577                 } else {
1578                         /* we don't understand the sense code, so it's
1579                          * probably pointless to loop */
1580                         if(!spintime) {
1581                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1582                                 sd_print_sense_hdr(sdkp, &sshdr);
1583                         }
1584                         break;
1585                 }
1586
1587         } while (spintime && time_before_eq(jiffies, spintime_expire));
1588
1589         if (spintime) {
1590                 if (scsi_status_is_good(the_result))
1591                         printk("ready\n");
1592                 else
1593                         printk("not responding...\n");
1594         }
1595 }
1596
1597
1598 /*
1599  * Determine whether disk supports Data Integrity Field.
1600  */
1601 static void sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
1602 {
1603         struct scsi_device *sdp = sdkp->device;
1604         u8 type;
1605
1606         if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
1607                 return;
1608
1609         type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
1610
1611         if (type == sdkp->protection_type || !sdkp->first_scan)
1612                 return;
1613
1614         sdkp->protection_type = type;
1615
1616         if (type > SD_DIF_TYPE3_PROTECTION) {
1617                 sd_printk(KERN_ERR, sdkp, "formatted with unsupported " \
1618                           "protection type %u. Disabling disk!\n", type);
1619                 sdkp->capacity = 0;
1620                 return;
1621         }
1622
1623         if (scsi_host_dif_capable(sdp->host, type))
1624                 sd_printk(KERN_NOTICE, sdkp,
1625                           "Enabling DIF Type %u protection\n", type);
1626         else
1627                 sd_printk(KERN_NOTICE, sdkp,
1628                           "Disabling DIF Type %u protection\n", type);
1629 }
1630
1631 static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
1632                         struct scsi_sense_hdr *sshdr, int sense_valid,
1633                         int the_result)
1634 {
1635         sd_print_result(sdkp, the_result);
1636         if (driver_byte(the_result) & DRIVER_SENSE)
1637                 sd_print_sense_hdr(sdkp, sshdr);
1638         else
1639                 sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
1640
1641         /*
1642          * Set dirty bit for removable devices if not ready -
1643          * sometimes drives will not report this properly.
1644          */
1645         if (sdp->removable &&
1646             sense_valid && sshdr->sense_key == NOT_READY)
1647                 set_media_not_present(sdkp);
1648
1649         /*
1650          * We used to set media_present to 0 here to indicate no media
1651          * in the drive, but some drives fail read capacity even with
1652          * media present, so we can't do that.
1653          */
1654         sdkp->capacity = 0; /* unknown mapped to zero - as usual */
1655 }
1656
1657 #define RC16_LEN 32
1658 #if RC16_LEN > SD_BUF_SIZE
1659 #error RC16_LEN must not be more than SD_BUF_SIZE
1660 #endif
1661
1662 #define READ_CAPACITY_RETRIES_ON_RESET  10
1663
1664 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
1665                                                 unsigned char *buffer)
1666 {
1667         unsigned char cmd[16];
1668         struct scsi_sense_hdr sshdr;
1669         int sense_valid = 0;
1670         int the_result;
1671         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1672         unsigned int alignment;
1673         unsigned long long lba;
1674         unsigned sector_size;
1675
1676         if (sdp->no_read_capacity_16)
1677                 return -EINVAL;
1678
1679         do {
1680                 memset(cmd, 0, 16);
1681                 cmd[0] = SERVICE_ACTION_IN;
1682                 cmd[1] = SAI_READ_CAPACITY_16;
1683                 cmd[13] = RC16_LEN;
1684                 memset(buffer, 0, RC16_LEN);
1685
1686                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1687                                         buffer, RC16_LEN, &sshdr,
1688                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1689
1690                 if (media_not_present(sdkp, &sshdr))
1691                         return -ENODEV;
1692
1693                 if (the_result) {
1694                         sense_valid = scsi_sense_valid(&sshdr);
1695                         if (sense_valid &&
1696                             sshdr.sense_key == ILLEGAL_REQUEST &&
1697                             (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1698                             sshdr.ascq == 0x00)
1699                                 /* Invalid Command Operation Code or
1700                                  * Invalid Field in CDB, just retry
1701                                  * silently with RC10 */
1702                                 return -EINVAL;
1703                         if (sense_valid &&
1704                             sshdr.sense_key == UNIT_ATTENTION &&
1705                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1706                                 /* Device reset might occur several times,
1707                                  * give it one more chance */
1708                                 if (--reset_retries > 0)
1709                                         continue;
1710                 }
1711                 retries--;
1712
1713         } while (the_result && retries);
1714
1715         if (the_result) {
1716                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY(16) failed\n");
1717                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1718                 return -EINVAL;
1719         }
1720
1721         sector_size = get_unaligned_be32(&buffer[8]);
1722         lba = get_unaligned_be64(&buffer[0]);
1723
1724         sd_read_protection_type(sdkp, buffer);
1725
1726         if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
1727                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1728                         "kernel compiled with support for large block "
1729                         "devices.\n");
1730                 sdkp->capacity = 0;
1731                 return -EOVERFLOW;
1732         }
1733
1734         /* Logical blocks per physical block exponent */
1735         sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
1736
1737         /* Lowest aligned logical block */
1738         alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
1739         blk_queue_alignment_offset(sdp->request_queue, alignment);
1740         if (alignment && sdkp->first_scan)
1741                 sd_printk(KERN_NOTICE, sdkp,
1742                           "physical block alignment offset: %u\n", alignment);
1743
1744         if (buffer[14] & 0x80) { /* LBPME */
1745                 sdkp->lbpme = 1;
1746
1747                 if (buffer[14] & 0x40) /* LBPRZ */
1748                         sdkp->lbprz = 1;
1749
1750                 sd_config_discard(sdkp, SD_LBP_WS16);
1751         }
1752
1753         sdkp->capacity = lba + 1;
1754         return sector_size;
1755 }
1756
1757 static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
1758                                                 unsigned char *buffer)
1759 {
1760         unsigned char cmd[16];
1761         struct scsi_sense_hdr sshdr;
1762         int sense_valid = 0;
1763         int the_result;
1764         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1765         sector_t lba;
1766         unsigned sector_size;
1767
1768         do {
1769                 cmd[0] = READ_CAPACITY;
1770                 memset(&cmd[1], 0, 9);
1771                 memset(buffer, 0, 8);
1772
1773                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1774                                         buffer, 8, &sshdr,
1775                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1776
1777                 if (media_not_present(sdkp, &sshdr))
1778                         return -ENODEV;
1779
1780                 if (the_result) {
1781                         sense_valid = scsi_sense_valid(&sshdr);
1782                         if (sense_valid &&
1783                             sshdr.sense_key == UNIT_ATTENTION &&
1784                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1785                                 /* Device reset might occur several times,
1786                                  * give it one more chance */
1787                                 if (--reset_retries > 0)
1788                                         continue;
1789                 }
1790                 retries--;
1791
1792         } while (the_result && retries);
1793
1794         if (the_result) {
1795                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY failed\n");
1796                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1797                 return -EINVAL;
1798         }
1799
1800         sector_size = get_unaligned_be32(&buffer[4]);
1801         lba = get_unaligned_be32(&buffer[0]);
1802
1803         if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
1804                 /* Some buggy (usb cardreader) devices return an lba of
1805                    0xffffffff when the want to report a size of 0 (with
1806                    which they really mean no media is present) */
1807                 sdkp->capacity = 0;
1808                 sdkp->physical_block_size = sector_size;
1809                 return sector_size;
1810         }
1811
1812         if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
1813                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1814                         "kernel compiled with support for large block "
1815                         "devices.\n");
1816                 sdkp->capacity = 0;
1817                 return -EOVERFLOW;
1818         }
1819
1820         sdkp->capacity = lba + 1;
1821         sdkp->physical_block_size = sector_size;
1822         return sector_size;
1823 }
1824
1825 static int sd_try_rc16_first(struct scsi_device *sdp)
1826 {
1827         if (sdp->host->max_cmd_len < 16)
1828                 return 0;
1829         if (sdp->scsi_level > SCSI_SPC_2)
1830                 return 1;
1831         if (scsi_device_protection(sdp))
1832                 return 1;
1833         return 0;
1834 }
1835
1836 /*
1837  * read disk capacity
1838  */
1839 static void
1840 sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
1841 {
1842         int sector_size;
1843         struct scsi_device *sdp = sdkp->device;
1844         sector_t old_capacity = sdkp->capacity;
1845
1846         if (sd_try_rc16_first(sdp)) {
1847                 sector_size = read_capacity_16(sdkp, sdp, buffer);
1848                 if (sector_size == -EOVERFLOW)
1849                         goto got_data;
1850                 if (sector_size == -ENODEV)
1851                         return;
1852                 if (sector_size < 0)
1853                         sector_size = read_capacity_10(sdkp, sdp, buffer);
1854                 if (sector_size < 0)
1855                         return;
1856         } else {
1857                 sector_size = read_capacity_10(sdkp, sdp, buffer);
1858                 if (sector_size == -EOVERFLOW)
1859                         goto got_data;
1860                 if (sector_size < 0)
1861                         return;
1862                 if ((sizeof(sdkp->capacity) > 4) &&
1863                     (sdkp->capacity > 0xffffffffULL)) {
1864                         int old_sector_size = sector_size;
1865                         sd_printk(KERN_NOTICE, sdkp, "Very big device. "
1866                                         "Trying to use READ CAPACITY(16).\n");
1867                         sector_size = read_capacity_16(sdkp, sdp, buffer);
1868                         if (sector_size < 0) {
1869                                 sd_printk(KERN_NOTICE, sdkp,
1870                                         "Using 0xffffffff as device size\n");
1871                                 sdkp->capacity = 1 + (sector_t) 0xffffffff;
1872                                 sector_size = old_sector_size;
1873                                 goto got_data;
1874                         }
1875                 }
1876         }
1877
1878         /* Some devices are known to return the total number of blocks,
1879          * not the highest block number.  Some devices have versions
1880          * which do this and others which do not.  Some devices we might
1881          * suspect of doing this but we don't know for certain.
1882          *
1883          * If we know the reported capacity is wrong, decrement it.  If
1884          * we can only guess, then assume the number of blocks is even
1885          * (usually true but not always) and err on the side of lowering
1886          * the capacity.
1887          */
1888         if (sdp->fix_capacity ||
1889             (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
1890                 sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
1891                                 "from its reported value: %llu\n",
1892                                 (unsigned long long) sdkp->capacity);
1893                 --sdkp->capacity;
1894         }
1895
1896 got_data:
1897         if (sector_size == 0) {
1898                 sector_size = 512;
1899                 sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
1900                           "assuming 512.\n");
1901         }
1902
1903         if (sector_size != 512 &&
1904             sector_size != 1024 &&
1905             sector_size != 2048 &&
1906             sector_size != 4096 &&
1907             sector_size != 256) {
1908                 sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
1909                           sector_size);
1910                 /*
1911                  * The user might want to re-format the drive with
1912                  * a supported sectorsize.  Once this happens, it
1913                  * would be relatively trivial to set the thing up.
1914                  * For this reason, we leave the thing in the table.
1915                  */
1916                 sdkp->capacity = 0;
1917                 /*
1918                  * set a bogus sector size so the normal read/write
1919                  * logic in the block layer will eventually refuse any
1920                  * request on this device without tripping over power
1921                  * of two sector size assumptions
1922                  */
1923                 sector_size = 512;
1924         }
1925         blk_queue_logical_block_size(sdp->request_queue, sector_size);
1926
1927         {
1928                 char cap_str_2[10], cap_str_10[10];
1929                 u64 sz = (u64)sdkp->capacity << ilog2(sector_size);
1930
1931                 string_get_size(sz, STRING_UNITS_2, cap_str_2,
1932                                 sizeof(cap_str_2));
1933                 string_get_size(sz, STRING_UNITS_10, cap_str_10,
1934                                 sizeof(cap_str_10));
1935
1936                 if (sdkp->first_scan || old_capacity != sdkp->capacity) {
1937                         sd_printk(KERN_NOTICE, sdkp,
1938                                   "%llu %d-byte logical blocks: (%s/%s)\n",
1939                                   (unsigned long long)sdkp->capacity,
1940                                   sector_size, cap_str_10, cap_str_2);
1941
1942                         if (sdkp->physical_block_size != sector_size)
1943                                 sd_printk(KERN_NOTICE, sdkp,
1944                                           "%u-byte physical blocks\n",
1945                                           sdkp->physical_block_size);
1946                 }
1947         }
1948
1949         /* Rescale capacity to 512-byte units */
1950         if (sector_size == 4096)
1951                 sdkp->capacity <<= 3;
1952         else if (sector_size == 2048)
1953                 sdkp->capacity <<= 2;
1954         else if (sector_size == 1024)
1955                 sdkp->capacity <<= 1;
1956         else if (sector_size == 256)
1957                 sdkp->capacity >>= 1;
1958
1959         blk_queue_physical_block_size(sdp->request_queue,
1960                                       sdkp->physical_block_size);
1961         sdkp->device->sector_size = sector_size;
1962 }
1963
1964 /* called with buffer of length 512 */
1965 static inline int
1966 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
1967                  unsigned char *buffer, int len, struct scsi_mode_data *data,
1968                  struct scsi_sense_hdr *sshdr)
1969 {
1970         return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
1971                                SD_TIMEOUT, SD_MAX_RETRIES, data,
1972                                sshdr);
1973 }
1974
1975 /*
1976  * read write protect setting, if possible - called only in sd_revalidate_disk()
1977  * called with buffer of length SD_BUF_SIZE
1978  */
1979 static void
1980 sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
1981 {
1982         int res;
1983         struct scsi_device *sdp = sdkp->device;
1984         struct scsi_mode_data data;
1985         int old_wp = sdkp->write_prot;
1986
1987         set_disk_ro(sdkp->disk, 0);
1988         if (sdp->skip_ms_page_3f) {
1989                 sd_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
1990                 return;
1991         }
1992
1993         if (sdp->use_192_bytes_for_3f) {
1994                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
1995         } else {
1996                 /*
1997                  * First attempt: ask for all pages (0x3F), but only 4 bytes.
1998                  * We have to start carefully: some devices hang if we ask
1999                  * for more than is available.
2000                  */
2001                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
2002
2003                 /*
2004                  * Second attempt: ask for page 0 When only page 0 is
2005                  * implemented, a request for page 3F may return Sense Key
2006                  * 5: Illegal Request, Sense Code 24: Invalid field in
2007                  * CDB.
2008                  */
2009                 if (!scsi_status_is_good(res))
2010                         res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
2011
2012                 /*
2013                  * Third attempt: ask 255 bytes, as we did earlier.
2014                  */
2015                 if (!scsi_status_is_good(res))
2016                         res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
2017                                                &data, NULL);
2018         }
2019
2020         if (!scsi_status_is_good(res)) {
2021                 sd_printk(KERN_WARNING, sdkp,
2022                           "Test WP failed, assume Write Enabled\n");
2023         } else {
2024                 sdkp->write_prot = ((data.device_specific & 0x80) != 0);
2025                 set_disk_ro(sdkp->disk, sdkp->write_prot);
2026                 if (sdkp->first_scan || old_wp != sdkp->write_prot) {
2027                         sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
2028                                   sdkp->write_prot ? "on" : "off");
2029                         sd_printk(KERN_DEBUG, sdkp,
2030                                   "Mode Sense: %02x %02x %02x %02x\n",
2031                                   buffer[0], buffer[1], buffer[2], buffer[3]);
2032                 }
2033         }
2034 }
2035
2036 /*
2037  * sd_read_cache_type - called only from sd_revalidate_disk()
2038  * called with buffer of length SD_BUF_SIZE
2039  */
2040 static void
2041 sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
2042 {
2043         int len = 0, res;
2044         struct scsi_device *sdp = sdkp->device;
2045
2046         int dbd;
2047         int modepage;
2048         int first_len;
2049         struct scsi_mode_data data;
2050         struct scsi_sense_hdr sshdr;
2051         int old_wce = sdkp->WCE;
2052         int old_rcd = sdkp->RCD;
2053         int old_dpofua = sdkp->DPOFUA;
2054
2055
2056         if (sdkp->cache_override)
2057                 return;
2058
2059         first_len = 4;
2060         if (sdp->skip_ms_page_8) {
2061                 if (sdp->type == TYPE_RBC)
2062                         goto defaults;
2063                 else {
2064                         if (sdp->skip_ms_page_3f)
2065                                 goto defaults;
2066                         modepage = 0x3F;
2067                         if (sdp->use_192_bytes_for_3f)
2068                                 first_len = 192;
2069                         dbd = 0;
2070                 }
2071         } else if (sdp->type == TYPE_RBC) {
2072                 modepage = 6;
2073                 dbd = 8;
2074         } else {
2075                 modepage = 8;
2076                 dbd = 0;
2077         }
2078
2079         /* cautiously ask */
2080         res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
2081                         &data, &sshdr);
2082
2083         if (!scsi_status_is_good(res))
2084                 goto bad_sense;
2085
2086         if (!data.header_length) {
2087                 modepage = 6;
2088                 first_len = 0;
2089                 sd_printk(KERN_ERR, sdkp, "Missing header in MODE_SENSE response\n");
2090         }
2091
2092         /* that went OK, now ask for the proper length */
2093         len = data.length;
2094
2095         /*
2096          * We're only interested in the first three bytes, actually.
2097          * But the data cache page is defined for the first 20.
2098          */
2099         if (len < 3)
2100                 goto bad_sense;
2101         else if (len > SD_BUF_SIZE) {
2102                 sd_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
2103                           "data from %d to %d bytes\n", len, SD_BUF_SIZE);
2104                 len = SD_BUF_SIZE;
2105         }
2106         if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
2107                 len = 192;
2108
2109         /* Get the data */
2110         if (len > first_len)
2111                 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
2112                                 &data, &sshdr);
2113
2114         if (scsi_status_is_good(res)) {
2115                 int offset = data.header_length + data.block_descriptor_length;
2116
2117                 while (offset < len) {
2118                         u8 page_code = buffer[offset] & 0x3F;
2119                         u8 spf       = buffer[offset] & 0x40;
2120
2121                         if (page_code == 8 || page_code == 6) {
2122                                 /* We're interested only in the first 3 bytes.
2123                                  */
2124                                 if (len - offset <= 2) {
2125                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2126                                                   "mode parameter data\n");
2127                                         goto defaults;
2128                                 } else {
2129                                         modepage = page_code;
2130                                         goto Page_found;
2131                                 }
2132                         } else {
2133                                 /* Go to the next page */
2134                                 if (spf && len - offset > 3)
2135                                         offset += 4 + (buffer[offset+2] << 8) +
2136                                                 buffer[offset+3];
2137                                 else if (!spf && len - offset > 1)
2138                                         offset += 2 + buffer[offset+1];
2139                                 else {
2140                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2141                                                   "mode parameter data\n");
2142                                         goto defaults;
2143                                 }
2144                         }
2145                 }
2146
2147                 if (modepage == 0x3F) {
2148                         sd_printk(KERN_ERR, sdkp, "No Caching mode page "
2149                                   "present\n");
2150                         goto defaults;
2151                 } else if ((buffer[offset] & 0x3f) != modepage) {
2152                         sd_printk(KERN_ERR, sdkp, "Got wrong page\n");
2153                         goto defaults;
2154                 }
2155         Page_found:
2156                 if (modepage == 8) {
2157                         sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
2158                         sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
2159                 } else {
2160                         sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
2161                         sdkp->RCD = 0;
2162                 }
2163
2164                 sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
2165                 if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
2166                         sd_printk(KERN_NOTICE, sdkp,
2167                                   "Uses READ/WRITE(6), disabling FUA\n");
2168                         sdkp->DPOFUA = 0;
2169                 }
2170
2171                 if (sdkp->first_scan || old_wce != sdkp->WCE ||
2172                     old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
2173                         sd_printk(KERN_NOTICE, sdkp,
2174                                   "Write cache: %s, read cache: %s, %s\n",
2175                                   sdkp->WCE ? "enabled" : "disabled",
2176                                   sdkp->RCD ? "disabled" : "enabled",
2177                                   sdkp->DPOFUA ? "supports DPO and FUA"
2178                                   : "doesn't support DPO or FUA");
2179
2180                 return;
2181         }
2182
2183 bad_sense:
2184         if (scsi_sense_valid(&sshdr) &&
2185             sshdr.sense_key == ILLEGAL_REQUEST &&
2186             sshdr.asc == 0x24 && sshdr.ascq == 0x0)
2187                 /* Invalid field in CDB */
2188                 sd_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
2189         else
2190                 sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n");
2191
2192 defaults:
2193         sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n");
2194         sdkp->WCE = 0;
2195         sdkp->RCD = 0;
2196         sdkp->DPOFUA = 0;
2197 }
2198
2199 /*
2200  * The ATO bit indicates whether the DIF application tag is available
2201  * for use by the operating system.
2202  */
2203 static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
2204 {
2205         int res, offset;
2206         struct scsi_device *sdp = sdkp->device;
2207         struct scsi_mode_data data;
2208         struct scsi_sense_hdr sshdr;
2209
2210         if (sdp->type != TYPE_DISK)
2211                 return;
2212
2213         if (sdkp->protection_type == 0)
2214                 return;
2215
2216         res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
2217                               SD_MAX_RETRIES, &data, &sshdr);
2218
2219         if (!scsi_status_is_good(res) || !data.header_length ||
2220             data.length < 6) {
2221                 sd_printk(KERN_WARNING, sdkp,
2222                           "getting Control mode page failed, assume no ATO\n");
2223
2224                 if (scsi_sense_valid(&sshdr))
2225                         sd_print_sense_hdr(sdkp, &sshdr);
2226
2227                 return;
2228         }
2229
2230         offset = data.header_length + data.block_descriptor_length;
2231
2232         if ((buffer[offset] & 0x3f) != 0x0a) {
2233                 sd_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
2234                 return;
2235         }
2236
2237         if ((buffer[offset + 5] & 0x80) == 0)
2238                 return;
2239
2240         sdkp->ATO = 1;
2241
2242         return;
2243 }
2244
2245 /**
2246  * sd_read_block_limits - Query disk device for preferred I/O sizes.
2247  * @disk: disk to query
2248  */
2249 static void sd_read_block_limits(struct scsi_disk *sdkp)
2250 {
2251         unsigned int sector_sz = sdkp->device->sector_size;
2252         const int vpd_len = 64;
2253         unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
2254
2255         if (!buffer ||
2256             /* Block Limits VPD */
2257             scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
2258                 goto out;
2259
2260         blk_queue_io_min(sdkp->disk->queue,
2261                          get_unaligned_be16(&buffer[6]) * sector_sz);
2262         blk_queue_io_opt(sdkp->disk->queue,
2263                          get_unaligned_be32(&buffer[12]) * sector_sz);
2264
2265         if (buffer[3] == 0x3c) {
2266                 unsigned int lba_count, desc_count;
2267
2268                 sdkp->max_ws_blocks =
2269                         (u32) min_not_zero(get_unaligned_be64(&buffer[36]),
2270                                            (u64)0xffffffff);
2271
2272                 if (!sdkp->lbpme)
2273                         goto out;
2274
2275                 lba_count = get_unaligned_be32(&buffer[20]);
2276                 desc_count = get_unaligned_be32(&buffer[24]);
2277
2278                 if (lba_count && desc_count)
2279                         sdkp->max_unmap_blocks = lba_count;
2280
2281                 sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
2282
2283                 if (buffer[32] & 0x80)
2284                         sdkp->unmap_alignment =
2285                                 get_unaligned_be32(&buffer[32]) & ~(1 << 31);
2286
2287                 if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
2288
2289                         if (sdkp->max_unmap_blocks)
2290                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2291                         else
2292                                 sd_config_discard(sdkp, SD_LBP_WS16);
2293
2294                 } else {        /* LBP VPD page tells us what to use */
2295
2296                         if (sdkp->lbpu && sdkp->max_unmap_blocks)
2297                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2298                         else if (sdkp->lbpws)
2299                                 sd_config_discard(sdkp, SD_LBP_WS16);
2300                         else if (sdkp->lbpws10)
2301                                 sd_config_discard(sdkp, SD_LBP_WS10);
2302                         else
2303                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
2304                 }
2305         }
2306
2307  out:
2308         kfree(buffer);
2309 }
2310
2311 /**
2312  * sd_read_block_characteristics - Query block dev. characteristics
2313  * @disk: disk to query
2314  */
2315 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
2316 {
2317         unsigned char *buffer;
2318         u16 rot;
2319         const int vpd_len = 64;
2320
2321         buffer = kmalloc(vpd_len, GFP_KERNEL);
2322
2323         if (!buffer ||
2324             /* Block Device Characteristics VPD */
2325             scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
2326                 goto out;
2327
2328         rot = get_unaligned_be16(&buffer[4]);
2329
2330         if (rot == 1)
2331                 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
2332
2333  out:
2334         kfree(buffer);
2335 }
2336
2337 /**
2338  * sd_read_block_provisioning - Query provisioning VPD page
2339  * @disk: disk to query
2340  */
2341 static void sd_read_block_provisioning(struct scsi_disk *sdkp)
2342 {
2343         unsigned char *buffer;
2344         const int vpd_len = 8;
2345
2346         if (sdkp->lbpme == 0)
2347                 return;
2348
2349         buffer = kmalloc(vpd_len, GFP_KERNEL);
2350
2351         if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
2352                 goto out;
2353
2354         sdkp->lbpvpd    = 1;
2355         sdkp->lbpu      = (buffer[5] >> 7) & 1; /* UNMAP */
2356         sdkp->lbpws     = (buffer[5] >> 6) & 1; /* WRITE SAME(16) with UNMAP */
2357         sdkp->lbpws10   = (buffer[5] >> 5) & 1; /* WRITE SAME(10) with UNMAP */
2358
2359  out:
2360         kfree(buffer);
2361 }
2362
2363 static int sd_try_extended_inquiry(struct scsi_device *sdp)
2364 {
2365         /*
2366          * Although VPD inquiries can go to SCSI-2 type devices,
2367          * some USB ones crash on receiving them, and the pages
2368          * we currently ask for are for SPC-3 and beyond
2369          */
2370         if (sdp->scsi_level > SCSI_SPC_2)
2371                 return 1;
2372         return 0;
2373 }
2374
2375 /**
2376  *      sd_revalidate_disk - called the first time a new disk is seen,
2377  *      performs disk spin up, read_capacity, etc.
2378  *      @disk: struct gendisk we care about
2379  **/
2380 static int sd_revalidate_disk(struct gendisk *disk)
2381 {
2382         struct scsi_disk *sdkp = scsi_disk(disk);
2383         struct scsi_device *sdp = sdkp->device;
2384         unsigned char *buffer;
2385         unsigned flush = 0;
2386
2387         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
2388                                       "sd_revalidate_disk\n"));
2389
2390         /*
2391          * If the device is offline, don't try and read capacity or any
2392          * of the other niceties.
2393          */
2394         if (!scsi_device_online(sdp))
2395                 goto out;
2396
2397         buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
2398         if (!buffer) {
2399                 sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
2400                           "allocation failure.\n");
2401                 goto out;
2402         }
2403
2404         sd_spinup_disk(sdkp);
2405
2406         /*
2407          * Without media there is no reason to ask; moreover, some devices
2408          * react badly if we do.
2409          */
2410         if (sdkp->media_present) {
2411                 sd_read_capacity(sdkp, buffer);
2412
2413                 if (sd_try_extended_inquiry(sdp)) {
2414                         sd_read_block_provisioning(sdkp);
2415                         sd_read_block_limits(sdkp);
2416                         sd_read_block_characteristics(sdkp);
2417                 }
2418
2419                 sd_read_write_protect_flag(sdkp, buffer);
2420                 sd_read_cache_type(sdkp, buffer);
2421                 sd_read_app_tag_own(sdkp, buffer);
2422         }
2423
2424         sdkp->first_scan = 0;
2425
2426         /*
2427          * We now have all cache related info, determine how we deal
2428          * with flush requests.
2429          */
2430         if (sdkp->WCE) {
2431                 flush |= REQ_FLUSH;
2432                 if (sdkp->DPOFUA)
2433                         flush |= REQ_FUA;
2434         }
2435
2436         blk_queue_flush(sdkp->disk->queue, flush);
2437
2438         set_capacity(disk, sdkp->capacity);
2439         kfree(buffer);
2440
2441  out:
2442         return 0;
2443 }
2444
2445 /**
2446  *      sd_unlock_native_capacity - unlock native capacity
2447  *      @disk: struct gendisk to set capacity for
2448  *
2449  *      Block layer calls this function if it detects that partitions
2450  *      on @disk reach beyond the end of the device.  If the SCSI host
2451  *      implements ->unlock_native_capacity() method, it's invoked to
2452  *      give it a chance to adjust the device capacity.
2453  *
2454  *      CONTEXT:
2455  *      Defined by block layer.  Might sleep.
2456  */
2457 static void sd_unlock_native_capacity(struct gendisk *disk)
2458 {
2459         struct scsi_device *sdev = scsi_disk(disk)->device;
2460
2461         if (sdev->host->hostt->unlock_native_capacity)
2462                 sdev->host->hostt->unlock_native_capacity(sdev);
2463 }
2464
2465 /**
2466  *      sd_format_disk_name - format disk name
2467  *      @prefix: name prefix - ie. "sd" for SCSI disks
2468  *      @index: index of the disk to format name for
2469  *      @buf: output buffer
2470  *      @buflen: length of the output buffer
2471  *
2472  *      SCSI disk names starts at sda.  The 26th device is sdz and the
2473  *      27th is sdaa.  The last one for two lettered suffix is sdzz
2474  *      which is followed by sdaaa.
2475  *
2476  *      This is basically 26 base counting with one extra 'nil' entry
2477  *      at the beginning from the second digit on and can be
2478  *      determined using similar method as 26 base conversion with the
2479  *      index shifted -1 after each digit is computed.
2480  *
2481  *      CONTEXT:
2482  *      Don't care.
2483  *
2484  *      RETURNS:
2485  *      0 on success, -errno on failure.
2486  */
2487 static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
2488 {
2489         const int base = 'z' - 'a' + 1;
2490         char *begin = buf + strlen(prefix);
2491         char *end = buf + buflen;
2492         char *p;
2493         int unit;
2494
2495         p = end - 1;
2496         *p = '\0';
2497         unit = base;
2498         do {
2499                 if (p == begin)
2500                         return -EINVAL;
2501                 *--p = 'a' + (index % unit);
2502                 index = (index / unit) - 1;
2503         } while (index >= 0);
2504
2505         memmove(begin, p, end - p);
2506         memcpy(buf, prefix, strlen(prefix));
2507
2508         return 0;
2509 }
2510
2511 /*
2512  * The asynchronous part of sd_probe
2513  */
2514 static void sd_probe_async(void *data, async_cookie_t cookie)
2515 {
2516         struct scsi_disk *sdkp = data;
2517         struct scsi_device *sdp;
2518         struct gendisk *gd;
2519         u32 index;
2520         struct device *dev;
2521
2522         sdp = sdkp->device;
2523         gd = sdkp->disk;
2524         index = sdkp->index;
2525         dev = &sdp->sdev_gendev;
2526
2527         gd->major = sd_major((index & 0xf0) >> 4);
2528         gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
2529         gd->minors = SD_MINORS;
2530
2531         gd->fops = &sd_fops;
2532         gd->private_data = &sdkp->driver;
2533         gd->queue = sdkp->device->request_queue;
2534
2535         /* defaults, until the device tells us otherwise */
2536         sdp->sector_size = 512;
2537         sdkp->capacity = 0;
2538         sdkp->media_present = 1;
2539         sdkp->write_prot = 0;
2540         sdkp->cache_override = 0;
2541         sdkp->WCE = 0;
2542         sdkp->RCD = 0;
2543         sdkp->ATO = 0;
2544         sdkp->first_scan = 1;
2545
2546         sd_revalidate_disk(gd);
2547
2548         blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
2549         blk_queue_unprep_rq(sdp->request_queue, sd_unprep_fn);
2550
2551         gd->driverfs_dev = &sdp->sdev_gendev;
2552         gd->flags = GENHD_FL_EXT_DEVT;
2553         if (sdp->removable) {
2554                 gd->flags |= GENHD_FL_REMOVABLE;
2555                 gd->events |= DISK_EVENT_MEDIA_CHANGE;
2556         }
2557
2558         add_disk(gd);
2559         sd_dif_config_host(sdkp);
2560
2561         sd_revalidate_disk(gd);
2562
2563         sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
2564                   sdp->removable ? "removable " : "");
2565         scsi_autopm_put_device(sdp);
2566         put_device(&sdkp->dev);
2567 }
2568
2569 /**
2570  *      sd_probe - called during driver initialization and whenever a
2571  *      new scsi device is attached to the system. It is called once
2572  *      for each scsi device (not just disks) present.
2573  *      @dev: pointer to device object
2574  *
2575  *      Returns 0 if successful (or not interested in this scsi device
2576  *      (e.g. scanner)); 1 when there is an error.
2577  *
2578  *      Note: this function is invoked from the scsi mid-level.
2579  *      This function sets up the mapping between a given
2580  *      <host,channel,id,lun> (found in sdp) and new device name
2581  *      (e.g. /dev/sda). More precisely it is the block device major
2582  *      and minor number that is chosen here.
2583  *
2584  *      Assume sd_attach is not re-entrant (for time being)
2585  *      Also think about sd_attach() and sd_remove() running coincidentally.
2586  **/
2587 static int sd_probe(struct device *dev)
2588 {
2589         struct scsi_device *sdp = to_scsi_device(dev);
2590         struct scsi_disk *sdkp;
2591         struct gendisk *gd;
2592         int index;
2593         int error;
2594
2595         error = -ENODEV;
2596         if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
2597                 goto out;
2598
2599         SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
2600                                         "sd_attach\n"));
2601
2602         error = -ENOMEM;
2603         sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
2604         if (!sdkp)
2605                 goto out;
2606
2607         gd = alloc_disk(SD_MINORS);
2608         if (!gd)
2609                 goto out_free;
2610
2611         do {
2612                 if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
2613                         goto out_put;
2614
2615                 spin_lock(&sd_index_lock);
2616                 error = ida_get_new(&sd_index_ida, &index);
2617                 spin_unlock(&sd_index_lock);
2618         } while (error == -EAGAIN);
2619
2620         if (error) {
2621                 sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
2622                 goto out_put;
2623         }
2624
2625         error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
2626         if (error) {
2627                 sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name length exceeded.\n");
2628                 goto out_free_index;
2629         }
2630
2631         sdkp->device = sdp;
2632         sdkp->driver = &sd_template;
2633         sdkp->disk = gd;
2634         sdkp->index = index;
2635         atomic_set(&sdkp->openers, 0);
2636
2637         if (!sdp->request_queue->rq_timeout) {
2638                 if (sdp->type != TYPE_MOD)
2639                         blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
2640                 else
2641                         blk_queue_rq_timeout(sdp->request_queue,
2642                                              SD_MOD_TIMEOUT);
2643         }
2644
2645         device_initialize(&sdkp->dev);
2646         sdkp->dev.parent = dev;
2647         sdkp->dev.class = &sd_disk_class;
2648         dev_set_name(&sdkp->dev, dev_name(dev));
2649
2650         if (device_add(&sdkp->dev))
2651                 goto out_free_index;
2652
2653         get_device(dev);
2654         dev_set_drvdata(dev, sdkp);
2655
2656         get_device(&sdkp->dev); /* prevent release before async_schedule */
2657         async_schedule(sd_probe_async, sdkp);
2658
2659         return 0;
2660
2661  out_free_index:
2662         spin_lock(&sd_index_lock);
2663         ida_remove(&sd_index_ida, index);
2664         spin_unlock(&sd_index_lock);
2665  out_put:
2666         put_disk(gd);
2667  out_free:
2668         kfree(sdkp);
2669  out:
2670         return error;
2671 }
2672
2673 /**
2674  *      sd_remove - called whenever a scsi disk (previously recognized by
2675  *      sd_probe) is detached from the system. It is called (potentially
2676  *      multiple times) during sd module unload.
2677  *      @sdp: pointer to mid level scsi device object
2678  *
2679  *      Note: this function is invoked from the scsi mid-level.
2680  *      This function potentially frees up a device name (e.g. /dev/sdc)
2681  *      that could be re-used by a subsequent sd_probe().
2682  *      This function is not called when the built-in sd driver is "exit-ed".
2683  **/
2684 static int sd_remove(struct device *dev)
2685 {
2686         struct scsi_disk *sdkp;
2687
2688         sdkp = dev_get_drvdata(dev);
2689         scsi_autopm_get_device(sdkp->device);
2690
2691         async_synchronize_full();
2692         blk_queue_prep_rq(sdkp->device->request_queue, scsi_prep_fn);
2693         blk_queue_unprep_rq(sdkp->device->request_queue, NULL);
2694         device_del(&sdkp->dev);
2695         del_gendisk(sdkp->disk);
2696         sd_shutdown(dev);
2697
2698         mutex_lock(&sd_ref_mutex);
2699         dev_set_drvdata(dev, NULL);
2700         put_device(&sdkp->dev);
2701         mutex_unlock(&sd_ref_mutex);
2702
2703         return 0;
2704 }
2705
2706 /**
2707  *      scsi_disk_release - Called to free the scsi_disk structure
2708  *      @dev: pointer to embedded class device
2709  *
2710  *      sd_ref_mutex must be held entering this routine.  Because it is
2711  *      called on last put, you should always use the scsi_disk_get()
2712  *      scsi_disk_put() helpers which manipulate the semaphore directly
2713  *      and never do a direct put_device.
2714  **/
2715 static void scsi_disk_release(struct device *dev)
2716 {
2717         struct scsi_disk *sdkp = to_scsi_disk(dev);
2718         struct gendisk *disk = sdkp->disk;
2719
2720         spin_lock(&sd_index_lock);
2721         ida_remove(&sd_index_ida, sdkp->index);
2722         spin_unlock(&sd_index_lock);
2723
2724         disk->private_data = NULL;
2725         put_disk(disk);
2726         put_device(&sdkp->device->sdev_gendev);
2727
2728         kfree(sdkp);
2729 }
2730
2731 static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
2732 {
2733         unsigned char cmd[6] = { START_STOP };  /* START_VALID */
2734         struct scsi_sense_hdr sshdr;
2735         struct scsi_device *sdp = sdkp->device;
2736         int res;
2737
2738         if (start)
2739                 cmd[4] |= 1;    /* START */
2740
2741         if (sdp->start_stop_pwr_cond)
2742                 cmd[4] |= start ? 1 << 4 : 3 << 4;      /* Active or Standby */
2743
2744         if (!scsi_device_online(sdp))
2745                 return -ENODEV;
2746
2747         res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
2748                                SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2749         if (res) {
2750                 sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n");
2751                 sd_print_result(sdkp, res);
2752                 if (driver_byte(res) & DRIVER_SENSE)
2753                         sd_print_sense_hdr(sdkp, &sshdr);
2754         }
2755
2756         return res;
2757 }
2758
2759 /*
2760  * Send a SYNCHRONIZE CACHE instruction down to the device through
2761  * the normal SCSI command structure.  Wait for the command to
2762  * complete.
2763  */
2764 static void sd_shutdown(struct device *dev)
2765 {
2766         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2767
2768         if (!sdkp)
2769                 return;         /* this can happen */
2770
2771         if (sdkp->WCE) {
2772                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2773                 sd_sync_cache(sdkp);
2774         }
2775
2776         if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
2777                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2778                 sd_start_stop_device(sdkp, 0);
2779         }
2780
2781         scsi_disk_put(sdkp);
2782 }
2783
2784 static int sd_suspend(struct device *dev, pm_message_t mesg)
2785 {
2786         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2787         int ret = 0;
2788
2789         if (!sdkp)
2790                 return 0;       /* this can happen */
2791
2792         if (sdkp->WCE) {
2793                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2794                 ret = sd_sync_cache(sdkp);
2795                 if (ret)
2796                         goto done;
2797         }
2798
2799         if ((mesg.event & PM_EVENT_SLEEP) && sdkp->device->manage_start_stop) {
2800                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2801                 ret = sd_start_stop_device(sdkp, 0);
2802         }
2803
2804 done:
2805         scsi_disk_put(sdkp);
2806         return ret;
2807 }
2808
2809 static int sd_resume(struct device *dev)
2810 {
2811         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2812         int ret = 0;
2813
2814         if (!sdkp->device->manage_start_stop)
2815                 goto done;
2816
2817         sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
2818         ret = sd_start_stop_device(sdkp, 1);
2819
2820 done:
2821         scsi_disk_put(sdkp);
2822         return ret;
2823 }
2824
2825 /**
2826  *      init_sd - entry point for this driver (both when built in or when
2827  *      a module).
2828  *
2829  *      Note: this function registers this driver with the scsi mid-level.
2830  **/
2831 static int __init init_sd(void)
2832 {
2833         int majors = 0, i, err;
2834
2835         SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
2836
2837         for (i = 0; i < SD_MAJORS; i++)
2838                 if (register_blkdev(sd_major(i), "sd") == 0)
2839                         majors++;
2840
2841         if (!majors)
2842                 return -ENODEV;
2843
2844         err = class_register(&sd_disk_class);
2845         if (err)
2846                 goto err_out;
2847
2848         sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
2849                                          0, 0, NULL);
2850         if (!sd_cdb_cache) {
2851                 printk(KERN_ERR "sd: can't init extended cdb cache\n");
2852                 goto err_out_class;
2853         }
2854
2855         sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
2856         if (!sd_cdb_pool) {
2857                 printk(KERN_ERR "sd: can't init extended cdb pool\n");
2858                 goto err_out_cache;
2859         }
2860
2861         err = scsi_register_driver(&sd_template.gendrv);
2862         if (err)
2863                 goto err_out_driver;
2864
2865         return 0;
2866
2867 err_out_driver:
2868         mempool_destroy(sd_cdb_pool);
2869
2870 err_out_cache:
2871         kmem_cache_destroy(sd_cdb_cache);
2872
2873 err_out_class:
2874         class_unregister(&sd_disk_class);
2875 err_out:
2876         for (i = 0; i < SD_MAJORS; i++)
2877                 unregister_blkdev(sd_major(i), "sd");
2878         return err;
2879 }
2880
2881 /**
2882  *      exit_sd - exit point for this driver (when it is a module).
2883  *
2884  *      Note: this function unregisters this driver from the scsi mid-level.
2885  **/
2886 static void __exit exit_sd(void)
2887 {
2888         int i;
2889
2890         SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
2891
2892         scsi_unregister_driver(&sd_template.gendrv);
2893         mempool_destroy(sd_cdb_pool);
2894         kmem_cache_destroy(sd_cdb_cache);
2895
2896         class_unregister(&sd_disk_class);
2897
2898         for (i = 0; i < SD_MAJORS; i++)
2899                 unregister_blkdev(sd_major(i), "sd");
2900 }
2901
2902 module_init(init_sd);
2903 module_exit(exit_sd);
2904
2905 static void sd_print_sense_hdr(struct scsi_disk *sdkp,
2906                                struct scsi_sense_hdr *sshdr)
2907 {
2908         sd_printk(KERN_INFO, sdkp, " ");
2909         scsi_show_sense_hdr(sshdr);
2910         sd_printk(KERN_INFO, sdkp, " ");
2911         scsi_show_extd_sense(sshdr->asc, sshdr->ascq);
2912 }
2913
2914 static void sd_print_result(struct scsi_disk *sdkp, int result)
2915 {
2916         sd_printk(KERN_INFO, sdkp, " ");
2917         scsi_show_result(result);
2918 }
2919