drivers/scsi/sd.c

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