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