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