drivers/scsi/scsi_sysfs.c

   1 /*
   2  * scsi_sysfs.c
   3  *
   4  * SCSI sysfs interface routines.
   5  *
   6  * Created to pull SCSI mid layer sysfs routines into one file.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/slab.h>
  11 #include <linux/init.h>
  12 #include <linux/blkdev.h>
  13 #include <linux/device.h>
  14 #include <linux/pm_runtime.h>
  15
  16 #include <scsi/scsi.h>
  17 #include <scsi/scsi_device.h>
  18 #include <scsi/scsi_host.h>
  19 #include <scsi/scsi_tcq.h>
  20 #include <scsi/scsi_dh.h>
  21 #include <scsi/scsi_transport.h>
  22 #include <scsi/scsi_driver.h>
  23
  24 #include "scsi_priv.h"
  25 #include "scsi_logging.h"
  26
  27 static struct device_type scsi_dev_type;
  28
  29 static const struct {
  30         enum scsi_device_state  value;
  31         char                    *name;
  32 } sdev_states[] = {
  33         { SDEV_CREATED, "created" },
  34         { SDEV_RUNNING, "running" },
  35         { SDEV_CANCEL, "cancel" },
  36         { SDEV_DEL, "deleted" },
  37         { SDEV_QUIESCE, "quiesce" },
  38         { SDEV_OFFLINE, "offline" },
  39         { SDEV_TRANSPORT_OFFLINE, "transport-offline" },
  40         { SDEV_BLOCK,   "blocked" },
  41         { SDEV_CREATED_BLOCK, "created-blocked" },
  42 };
  43
  44 const char *scsi_device_state_name(enum scsi_device_state state)
  45 {
  46         int i;
  47         char *name = NULL;
  48
  49         for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
  50                 if (sdev_states[i].value == state) {
  51                         name = sdev_states[i].name;
  52                         break;
  53                 }
  54         }
  55         return name;
  56 }
  57
  58 static const struct {
  59         enum scsi_host_state    value;
  60         char                    *name;
  61 } shost_states[] = {
  62         { SHOST_CREATED, "created" },
  63         { SHOST_RUNNING, "running" },
  64         { SHOST_CANCEL, "cancel" },
  65         { SHOST_DEL, "deleted" },
  66         { SHOST_RECOVERY, "recovery" },
  67         { SHOST_CANCEL_RECOVERY, "cancel/recovery" },
  68         { SHOST_DEL_RECOVERY, "deleted/recovery", },
  69 };
  70 const char *scsi_host_state_name(enum scsi_host_state state)
  71 {
  72         int i;
  73         char *name = NULL;
  74
  75         for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
  76                 if (shost_states[i].value == state) {
  77                         name = shost_states[i].name;
  78                         break;
  79                 }
  80         }
  81         return name;
  82 }
  83
  84 #ifdef CONFIG_SCSI_DH
  85 static const struct {
  86         unsigned char   value;
  87         char            *name;
  88 } sdev_access_states[] = {
  89         { SCSI_ACCESS_STATE_OPTIMAL, "active/optimized" },
  90         { SCSI_ACCESS_STATE_ACTIVE, "active/non-optimized" },
  91         { SCSI_ACCESS_STATE_STANDBY, "standby" },
  92         { SCSI_ACCESS_STATE_UNAVAILABLE, "unavailable" },
  93         { SCSI_ACCESS_STATE_LBA, "lba-dependent" },
  94         { SCSI_ACCESS_STATE_OFFLINE, "offline" },
  95         { SCSI_ACCESS_STATE_TRANSITIONING, "transitioning" },
  96 };
  97
  98 static const char *scsi_access_state_name(unsigned char state)
  99 {
 100         int i;
 101         char *name = NULL;
 102
 103         for (i = 0; i < ARRAY_SIZE(sdev_access_states); i++) {
 104                 if (sdev_access_states[i].value == state) {
 105                         name = sdev_access_states[i].name;
 106                         break;
 107                 }
 108         }
 109         return name;
 110 }
 111 #endif
 112
 113 static int check_set(unsigned long long *val, char *src)
 114 {
 115         char *last;
 116
 117         if (strncmp(src, "-", 20) == 0) {
 118                 *val = SCAN_WILD_CARD;
 119         } else {
 120                 /*
 121                  * Doesn't check for int overflow
 122                  */
 123                 *val = simple_strtoull(src, &last, 0);
 124                 if (*last != '\0')
 125                         return 1;
 126         }
 127         return 0;
 128 }
 129
 130 static int scsi_scan(struct Scsi_Host *shost, const char *str)
 131 {
 132         char s1[15], s2[15], s3[17], junk;
 133         unsigned long long channel, id, lun;
 134         int res;
 135
 136         res = sscanf(str, "%10s %10s %16s %c", s1, s2, s3, &junk);
 137         if (res != 3)
 138                 return -EINVAL;
 139         if (check_set(&channel, s1))
 140                 return -EINVAL;
 141         if (check_set(&id, s2))
 142                 return -EINVAL;
 143         if (check_set(&lun, s3))
 144                 return -EINVAL;
 145         if (shost->transportt->user_scan)
 146                 res = shost->transportt->user_scan(shost, channel, id, lun);
 147         else
 148                 res = scsi_scan_host_selected(shost, channel, id, lun,
 149                                               SCSI_SCAN_MANUAL);
 150         return res;
 151 }
 152
 153 /*
 154  * shost_show_function: macro to create an attr function that can be used to
 155  * show a non-bit field.
 156  */
 157 #define shost_show_function(name, field, format_string)                 \
 158 static ssize_t                                                          \
 159 show_##name (struct device *dev, struct device_attribute *attr,         \
 160              char *buf)                                                 \
 161 {                                                                       \
 162         struct Scsi_Host *shost = class_to_shost(dev);                  \
 163         return snprintf (buf, 20, format_string, shost->field);         \
 164 }
 165
 166 /*
 167  * shost_rd_attr: macro to create a function and attribute variable for a
 168  * read only field.
 169  */
 170 #define shost_rd_attr2(name, field, format_string)                      \
 171         shost_show_function(name, field, format_string)                 \
 172 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
 173
 174 #define shost_rd_attr(field, format_string) \
 175 shost_rd_attr2(field, field, format_string)
 176
 177 /*
 178  * Create the actual show/store functions and data structures.
 179  */
 180
 181 static ssize_t
 182 store_scan(struct device *dev, struct device_attribute *attr,
 183            const char *buf, size_t count)
 184 {
 185         struct Scsi_Host *shost = class_to_shost(dev);
 186         int res;
 187
 188         res = scsi_scan(shost, buf);
 189         if (res == 0)
 190                 res = count;
 191         return res;
 192 };
 193 static DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
 194
 195 static ssize_t
 196 store_shost_state(struct device *dev, struct device_attribute *attr,
 197                   const char *buf, size_t count)
 198 {
 199         int i;
 200         struct Scsi_Host *shost = class_to_shost(dev);
 201         enum scsi_host_state state = 0;
 202
 203         for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
 204                 const int len = strlen(shost_states[i].name);
 205                 if (strncmp(shost_states[i].name, buf, len) == 0 &&
 206                    buf[len] == '\n') {
 207                         state = shost_states[i].value;
 208                         break;
 209                 }
 210         }
 211         if (!state)
 212                 return -EINVAL;
 213
 214         if (scsi_host_set_state(shost, state))
 215                 return -EINVAL;
 216         return count;
 217 }
 218
 219 static ssize_t
 220 show_shost_state(struct device *dev, struct device_attribute *attr, char *buf)
 221 {
 222         struct Scsi_Host *shost = class_to_shost(dev);
 223         const char *name = scsi_host_state_name(shost->shost_state);
 224
 225         if (!name)
 226                 return -EINVAL;
 227
 228         return snprintf(buf, 20, "%s\n", name);
 229 }
 230
 231 /* DEVICE_ATTR(state) clashes with dev_attr_state for sdev */
 232 static struct device_attribute dev_attr_hstate =
 233         __ATTR(state, S_IRUGO | S_IWUSR, show_shost_state, store_shost_state);
 234
 235 static ssize_t
 236 show_shost_mode(unsigned int mode, char *buf)
 237 {
 238         ssize_t len = 0;
 239
 240         if (mode & MODE_INITIATOR)
 241                 len = sprintf(buf, "%s", "Initiator");
 242
 243         if (mode & MODE_TARGET)
 244                 len += sprintf(buf + len, "%s%s", len ? ", " : "", "Target");
 245
 246         len += sprintf(buf + len, "\n");
 247
 248         return len;
 249 }
 250
 251 static ssize_t
 252 show_shost_supported_mode(struct device *dev, struct device_attribute *attr,
 253                           char *buf)
 254 {
 255         struct Scsi_Host *shost = class_to_shost(dev);
 256         unsigned int supported_mode = shost->hostt->supported_mode;
 257
 258         if (supported_mode == MODE_UNKNOWN)
 259                 /* by default this should be initiator */
 260                 supported_mode = MODE_INITIATOR;
 261
 262         return show_shost_mode(supported_mode, buf);
 263 }
 264
 265 static DEVICE_ATTR(supported_mode, S_IRUGO | S_IWUSR, show_shost_supported_mode, NULL);
 266
 267 static ssize_t
 268 show_shost_active_mode(struct device *dev,
 269                        struct device_attribute *attr, char *buf)
 270 {
 271         struct Scsi_Host *shost = class_to_shost(dev);
 272
 273         if (shost->active_mode == MODE_UNKNOWN)
 274                 return snprintf(buf, 20, "unknown\n");
 275         else
 276                 return show_shost_mode(shost->active_mode, buf);
 277 }
 278
 279 static DEVICE_ATTR(active_mode, S_IRUGO | S_IWUSR, show_shost_active_mode, NULL);
 280
 281 static int check_reset_type(const char *str)
 282 {
 283         if (sysfs_streq(str, "adapter"))
 284                 return SCSI_ADAPTER_RESET;
 285         else if (sysfs_streq(str, "firmware"))
 286                 return SCSI_FIRMWARE_RESET;
 287         else
 288                 return 0;
 289 }
 290
 291 static ssize_t
 292 store_host_reset(struct device *dev, struct device_attribute *attr,
 293                 const char *buf, size_t count)
 294 {
 295         struct Scsi_Host *shost = class_to_shost(dev);
 296         struct scsi_host_template *sht = shost->hostt;
 297         int ret = -EINVAL;
 298         int type;
 299
 300         type = check_reset_type(buf);
 301         if (!type)
 302                 goto exit_store_host_reset;
 303
 304         if (sht->host_reset)
 305                 ret = sht->host_reset(shost, type);
 306
 307 exit_store_host_reset:
 308         if (ret == 0)
 309                 ret = count;
 310         return ret;
 311 }
 312
 313 static DEVICE_ATTR(host_reset, S_IWUSR, NULL, store_host_reset);
 314
 315 static ssize_t
 316 show_shost_eh_deadline(struct device *dev,
 317                       struct device_attribute *attr, char *buf)
 318 {
 319         struct Scsi_Host *shost = class_to_shost(dev);
 320
 321         if (shost->eh_deadline == -1)
 322                 return snprintf(buf, strlen("off") + 2, "off\n");
 323         return sprintf(buf, "%u\n", shost->eh_deadline / HZ);
 324 }
 325
 326 static ssize_t
 327 store_shost_eh_deadline(struct device *dev, struct device_attribute *attr,
 328                 const char *buf, size_t count)
 329 {
 330         struct Scsi_Host *shost = class_to_shost(dev);
 331         int ret = -EINVAL;
 332         unsigned long deadline, flags;
 333
 334         if (shost->transportt &&
 335             (shost->transportt->eh_strategy_handler ||
 336              !shost->hostt->eh_host_reset_handler))
 337                 return ret;
 338
 339         if (!strncmp(buf, "off", strlen("off")))
 340                 deadline = -1;
 341         else {
 342                 ret = kstrtoul(buf, 10, &deadline);
 343                 if (ret)
 344                         return ret;
 345                 if (deadline * HZ > UINT_MAX)
 346                         return -EINVAL;
 347         }
 348
 349         spin_lock_irqsave(shost->host_lock, flags);
 350         if (scsi_host_in_recovery(shost))
 351                 ret = -EBUSY;
 352         else {
 353                 if (deadline == -1)
 354                         shost->eh_deadline = -1;
 355                 else
 356                         shost->eh_deadline = deadline * HZ;
 357
 358                 ret = count;
 359         }
 360         spin_unlock_irqrestore(shost->host_lock, flags);
 361
 362         return ret;
 363 }
 364
 365 static DEVICE_ATTR(eh_deadline, S_IRUGO | S_IWUSR, show_shost_eh_deadline, store_shost_eh_deadline);
 366
 367 shost_rd_attr(use_blk_mq, "%d\n");
 368 shost_rd_attr(unique_id, "%u\n");
 369 shost_rd_attr(cmd_per_lun, "%hd\n");
 370 shost_rd_attr(can_queue, "%hd\n");
 371 shost_rd_attr(sg_tablesize, "%hu\n");
 372 shost_rd_attr(sg_prot_tablesize, "%hu\n");
 373 shost_rd_attr(unchecked_isa_dma, "%d\n");
 374 shost_rd_attr(prot_capabilities, "%u\n");
 375 shost_rd_attr(prot_guard_type, "%hd\n");
 376 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
 377
 378 static ssize_t
 379 show_host_busy(struct device *dev, struct device_attribute *attr, char *buf)
 380 {
 381         struct Scsi_Host *shost = class_to_shost(dev);
 382         return snprintf(buf, 20, "%d\n", atomic_read(&shost->host_busy));
 383 }
 384 static DEVICE_ATTR(host_busy, S_IRUGO, show_host_busy, NULL);
 385
 386 static struct attribute *scsi_sysfs_shost_attrs[] = {
 387         &dev_attr_use_blk_mq.attr,
 388         &dev_attr_unique_id.attr,
 389         &dev_attr_host_busy.attr,
 390         &dev_attr_cmd_per_lun.attr,
 391         &dev_attr_can_queue.attr,
 392         &dev_attr_sg_tablesize.attr,
 393         &dev_attr_sg_prot_tablesize.attr,
 394         &dev_attr_unchecked_isa_dma.attr,
 395         &dev_attr_proc_name.attr,
 396         &dev_attr_scan.attr,
 397         &dev_attr_hstate.attr,
 398         &dev_attr_supported_mode.attr,
 399         &dev_attr_active_mode.attr,
 400         &dev_attr_prot_capabilities.attr,
 401         &dev_attr_prot_guard_type.attr,
 402         &dev_attr_host_reset.attr,
 403         &dev_attr_eh_deadline.attr,
 404         NULL
 405 };
 406
 407 static struct attribute_group scsi_shost_attr_group = {
 408         .attrs =        scsi_sysfs_shost_attrs,
 409 };
 410
 411 const struct attribute_group *scsi_sysfs_shost_attr_groups[] = {
 412         &scsi_shost_attr_group,
 413         NULL
 414 };
 415
 416 static void scsi_device_cls_release(struct device *class_dev)
 417 {
 418         struct scsi_device *sdev;
 419
 420         sdev = class_to_sdev(class_dev);
 421         put_device(&sdev->sdev_gendev);
 422 }
 423
 424 static void scsi_device_dev_release_usercontext(struct work_struct *work)
 425 {
 426         struct scsi_device *sdev;
 427         struct device *parent;
 428         struct list_head *this, *tmp;
 429         unsigned long flags;
 430
 431         sdev = container_of(work, struct scsi_device, ew.work);
 432
 433         scsi_dh_release_device(sdev);
 434
 435         parent = sdev->sdev_gendev.parent;
 436
 437         spin_lock_irqsave(sdev->host->host_lock, flags);
 438         list_del(&sdev->siblings);
 439         list_del(&sdev->same_target_siblings);
 440         list_del(&sdev->starved_entry);
 441         spin_unlock_irqrestore(sdev->host->host_lock, flags);
 442
 443         cancel_work_sync(&sdev->event_work);
 444
 445         list_for_each_safe(this, tmp, &sdev->event_list) {
 446                 struct scsi_event *evt;
 447
 448                 evt = list_entry(this, struct scsi_event, node);
 449                 list_del(&evt->node);
 450                 kfree(evt);
 451         }
 452
 453         blk_put_queue(sdev->request_queue);
 454         /* NULL queue means the device can't be used */
 455         sdev->request_queue = NULL;
 456
 457         kfree(sdev->vpd_pg83);
 458         kfree(sdev->vpd_pg80);
 459         kfree(sdev->inquiry);
 460         kfree(sdev);
 461
 462         if (parent)
 463                 put_device(parent);
 464 }
 465
 466 static void scsi_device_dev_release(struct device *dev)
 467 {
 468         struct scsi_device *sdp = to_scsi_device(dev);
 469         execute_in_process_context(scsi_device_dev_release_usercontext,
 470                                    &sdp->ew);
 471 }
 472
 473 static struct class sdev_class = {
 474         .name           = "scsi_device",
 475         .dev_release    = scsi_device_cls_release,
 476 };
 477
 478 /* all probing is done in the individual ->probe routines */
 479 static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
 480 {
 481         struct scsi_device *sdp;
 482
 483         if (dev->type != &scsi_dev_type)
 484                 return 0;
 485
 486         sdp = to_scsi_device(dev);
 487         if (sdp->no_uld_attach)
 488                 return 0;
 489         return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
 490 }
 491
 492 static int scsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
 493 {
 494         struct scsi_device *sdev;
 495
 496         if (dev->type != &scsi_dev_type)
 497                 return 0;
 498
 499         sdev = to_scsi_device(dev);
 500
 501         add_uevent_var(env, "MODALIAS=" SCSI_DEVICE_MODALIAS_FMT, sdev->type);
 502         return 0;
 503 }
 504
 505 struct bus_type scsi_bus_type = {
 506         .name           = "scsi",
 507         .match          = scsi_bus_match,
 508         .uevent         = scsi_bus_uevent,
 509 #ifdef CONFIG_PM
 510         .pm             = &scsi_bus_pm_ops,
 511 #endif
 512 };
 513 EXPORT_SYMBOL_GPL(scsi_bus_type);
 514
 515 int scsi_sysfs_register(void)
 516 {
 517         int error;
 518
 519         error = bus_register(&scsi_bus_type);
 520         if (!error) {
 521                 error = class_register(&sdev_class);
 522                 if (error)
 523                         bus_unregister(&scsi_bus_type);
 524         }
 525
 526         return error;
 527 }
 528
 529 void scsi_sysfs_unregister(void)
 530 {
 531         class_unregister(&sdev_class);
 532         bus_unregister(&scsi_bus_type);
 533 }
 534
 535 /*
 536  * sdev_show_function: macro to create an attr function that can be used to
 537  * show a non-bit field.
 538  */
 539 #define sdev_show_function(field, format_string)                                \
 540 static ssize_t                                                          \
 541 sdev_show_##field (struct device *dev, struct device_attribute *attr,   \
 542                    char *buf)                                           \
 543 {                                                                       \
 544         struct scsi_device *sdev;                                       \
 545         sdev = to_scsi_device(dev);                                     \
 546         return snprintf (buf, 20, format_string, sdev->field);          \
 547 }                                                                       \
 548
 549 /*
 550  * sdev_rd_attr: macro to create a function and attribute variable for a
 551  * read only field.
 552  */
 553 #define sdev_rd_attr(field, format_string)                              \
 554         sdev_show_function(field, format_string)                        \
 555 static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
 556
 557
 558 /*
 559  * sdev_rw_attr: create a function and attribute variable for a
 560  * read/write field.
 561  */
 562 #define sdev_rw_attr(field, format_string)                              \
 563         sdev_show_function(field, format_string)                                \
 564                                                                         \
 565 static ssize_t                                                          \
 566 sdev_store_##field (struct device *dev, struct device_attribute *attr,  \
 567                     const char *buf, size_t count)                      \
 568 {                                                                       \
 569         struct scsi_device *sdev;                                       \
 570         sdev = to_scsi_device(dev);                                     \
 571         sscanf (buf, format_string, &sdev->field);                      \
 572         return count;                                                   \
 573 }                                                                       \
 574 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
 575
 576 /* Currently we don't export bit fields, but we might in future,
 577  * so leave this code in */
 578 #if 0
 579 /*
 580  * sdev_rd_attr: create a function and attribute variable for a
 581  * read/write bit field.
 582  */
 583 #define sdev_rw_attr_bit(field)                                         \
 584         sdev_show_function(field, "%d\n")                                       \
 585                                                                         \
 586 static ssize_t                                                          \
 587 sdev_store_##field (struct device *dev, struct device_attribute *attr,  \
 588                     const char *buf, size_t count)                      \
 589 {                                                                       \
 590         int ret;                                                        \
 591         struct scsi_device *sdev;                                       \
 592         ret = scsi_sdev_check_buf_bit(buf);                             \
 593         if (ret >= 0)   {                                               \
 594                 sdev = to_scsi_device(dev);                             \
 595                 sdev->field = ret;                                      \
 596                 ret = count;                                            \
 597         }                                                               \
 598         return ret;                                                     \
 599 }                                                                       \
 600 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
 601
 602 /*
 603  * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
 604  * else return -EINVAL.
 605  */
 606 static int scsi_sdev_check_buf_bit(const char *buf)
 607 {
 608         if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
 609                 if (buf[0] == '1')
 610                         return 1;
 611                 else if (buf[0] == '0')
 612                         return 0;
 613                 else
 614                         return -EINVAL;
 615         } else
 616                 return -EINVAL;
 617 }
 618 #endif
 619 /*
 620  * Create the actual show/store functions and data structures.
 621  */
 622 sdev_rd_attr (type, "%d\n");
 623 sdev_rd_attr (scsi_level, "%d\n");
 624 sdev_rd_attr (vendor, "%.8s\n");
 625 sdev_rd_attr (model, "%.16s\n");
 626 sdev_rd_attr (rev, "%.4s\n");
 627
 628 static ssize_t
 629 sdev_show_device_busy(struct device *dev, struct device_attribute *attr,
 630                 char *buf)
 631 {
 632         struct scsi_device *sdev = to_scsi_device(dev);
 633         return snprintf(buf, 20, "%d\n", atomic_read(&sdev->device_busy));
 634 }
 635 static DEVICE_ATTR(device_busy, S_IRUGO, sdev_show_device_busy, NULL);
 636
 637 static ssize_t
 638 sdev_show_device_blocked(struct device *dev, struct device_attribute *attr,
 639                 char *buf)
 640 {
 641         struct scsi_device *sdev = to_scsi_device(dev);
 642         return snprintf(buf, 20, "%d\n", atomic_read(&sdev->device_blocked));
 643 }
 644 static DEVICE_ATTR(device_blocked, S_IRUGO, sdev_show_device_blocked, NULL);
 645
 646 /*
 647  * TODO: can we make these symlinks to the block layer ones?
 648  */
 649 static ssize_t
 650 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
 651 {
 652         struct scsi_device *sdev;
 653         sdev = to_scsi_device(dev);
 654         return snprintf(buf, 20, "%d\n", sdev->request_queue->rq_timeout / HZ);
 655 }
 656
 657 static ssize_t
 658 sdev_store_timeout (struct device *dev, struct device_attribute *attr,
 659                     const char *buf, size_t count)
 660 {
 661         struct scsi_device *sdev;
 662         int timeout;
 663         sdev = to_scsi_device(dev);
 664         sscanf (buf, "%d\n", &timeout);
 665         blk_queue_rq_timeout(sdev->request_queue, timeout * HZ);
 666         return count;
 667 }
 668 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
 669
 670 static ssize_t
 671 sdev_show_eh_timeout(struct device *dev, struct device_attribute *attr, char *buf)
 672 {
 673         struct scsi_device *sdev;
 674         sdev = to_scsi_device(dev);
 675         return snprintf(buf, 20, "%u\n", sdev->eh_timeout / HZ);
 676 }
 677
 678 static ssize_t
 679 sdev_store_eh_timeout(struct device *dev, struct device_attribute *attr,
 680                     const char *buf, size_t count)
 681 {
 682         struct scsi_device *sdev;
 683         unsigned int eh_timeout;
 684         int err;
 685
 686         if (!capable(CAP_SYS_ADMIN))
 687                 return -EACCES;
 688
 689         sdev = to_scsi_device(dev);
 690         err = kstrtouint(buf, 10, &eh_timeout);
 691         if (err)
 692                 return err;
 693         sdev->eh_timeout = eh_timeout * HZ;
 694
 695         return count;
 696 }
 697 static DEVICE_ATTR(eh_timeout, S_IRUGO | S_IWUSR, sdev_show_eh_timeout, sdev_store_eh_timeout);
 698
 699 static ssize_t
 700 store_rescan_field (struct device *dev, struct device_attribute *attr,
 701                     const char *buf, size_t count)
 702 {
 703         scsi_rescan_device(dev);
 704         return count;
 705 }
 706 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
 707
 708 static ssize_t
 709 sdev_store_delete(struct device *dev, struct device_attribute *attr,
 710                   const char *buf, size_t count)
 711 {
 712         struct kernfs_node *kn;
 713         struct scsi_device *sdev = to_scsi_device(dev);
 714
 715         /*
 716          * We need to try to get module, avoiding the module been removed
 717          * during delete.
 718          */
 719         if (scsi_device_get(sdev))
 720                 return -ENODEV;
 721
 722         kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
 723         WARN_ON_ONCE(!kn);
 724         /*
 725          * Concurrent writes into the "delete" sysfs attribute may trigger
 726          * concurrent calls to device_remove_file() and scsi_remove_device().
 727          * device_remove_file() handles concurrent removal calls by
 728          * serializing these and by ignoring the second and later removal
 729          * attempts.  Concurrent calls of scsi_remove_device() are
 730          * serialized. The second and later calls of scsi_remove_device() are
 731          * ignored because the first call of that function changes the device
 732          * state into SDEV_DEL.
 733          */
 734         device_remove_file(dev, attr);
 735         scsi_remove_device(sdev);
 736         if (kn)
 737                 sysfs_unbreak_active_protection(kn);
 738         scsi_device_put(sdev);
 739         return count;
 740 };
 741 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
 742
 743 static ssize_t
 744 store_state_field(struct device *dev, struct device_attribute *attr,
 745                   const char *buf, size_t count)
 746 {
 747         int i;
 748         struct scsi_device *sdev = to_scsi_device(dev);
 749         enum scsi_device_state state = 0;
 750
 751         for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
 752                 const int len = strlen(sdev_states[i].name);
 753                 if (strncmp(sdev_states[i].name, buf, len) == 0 &&
 754                    buf[len] == '\n') {
 755                         state = sdev_states[i].value;
 756                         break;
 757                 }
 758         }
 759         if (!state)
 760                 return -EINVAL;
 761
 762         if (scsi_device_set_state(sdev, state))
 763                 return -EINVAL;
 764         return count;
 765 }
 766
 767 static ssize_t
 768 show_state_field(struct device *dev, struct device_attribute *attr, char *buf)
 769 {
 770         struct scsi_device *sdev = to_scsi_device(dev);
 771         const char *name = scsi_device_state_name(sdev->sdev_state);
 772
 773         if (!name)
 774                 return -EINVAL;
 775
 776         return snprintf(buf, 20, "%s\n", name);
 777 }
 778
 779 static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
 780
 781 static ssize_t
 782 show_queue_type_field(struct device *dev, struct device_attribute *attr,
 783                       char *buf)
 784 {
 785         struct scsi_device *sdev = to_scsi_device(dev);
 786         const char *name = "none";
 787
 788         if (sdev->simple_tags)
 789                 name = "simple";
 790
 791         return snprintf(buf, 20, "%s\n", name);
 792 }
 793
 794 static ssize_t
 795 store_queue_type_field(struct device *dev, struct device_attribute *attr,
 796                        const char *buf, size_t count)
 797 {
 798         struct scsi_device *sdev = to_scsi_device(dev);
 799
 800         if (!sdev->tagged_supported)
 801                 return -EINVAL;
 802
 803         sdev_printk(KERN_INFO, sdev,
 804                     "ignoring write to deprecated queue_type attribute");
 805         return count;
 806 }
 807
 808 static DEVICE_ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
 809                    store_queue_type_field);
 810
 811 #define sdev_vpd_pg_attr(_page)                                         \
 812 static ssize_t                                                  \
 813 show_vpd_##_page(struct file *filp, struct kobject *kobj,       \
 814                  struct bin_attribute *bin_attr,                        \
 815                  char *buf, loff_t off, size_t count)                   \
 816 {                                                                       \
 817         struct device *dev = container_of(kobj, struct device, kobj);   \
 818         struct scsi_device *sdev = to_scsi_device(dev);                 \
 819         int ret;                                                        \
 820         if (!sdev->vpd_##_page)                                         \
 821                 return -EINVAL;                                         \
 822         rcu_read_lock();                                                \
 823         ret = memory_read_from_buffer(buf, count, &off,                 \
 824                                       rcu_dereference(sdev->vpd_##_page), \
 825                                        sdev->vpd_##_page##_len);        \
 826         rcu_read_unlock();                                              \
 827         return ret;                                             \
 828 }                                                                       \
 829 static struct bin_attribute dev_attr_vpd_##_page = {            \
 830         .attr = {.name = __stringify(vpd_##_page), .mode = S_IRUGO },   \
 831         .size = 0,                                                      \
 832         .read = show_vpd_##_page,                                       \
 833 };
 834
 835 sdev_vpd_pg_attr(pg83);
 836 sdev_vpd_pg_attr(pg80);
 837
 838 static ssize_t show_inquiry(struct file *filep, struct kobject *kobj,
 839                             struct bin_attribute *bin_attr,
 840                             char *buf, loff_t off, size_t count)
 841 {
 842         struct device *dev = container_of(kobj, struct device, kobj);
 843         struct scsi_device *sdev = to_scsi_device(dev);
 844
 845         if (!sdev->inquiry)
 846                 return -EINVAL;
 847
 848         return memory_read_from_buffer(buf, count, &off, sdev->inquiry,
 849                                        sdev->inquiry_len);
 850 }
 851
 852 static struct bin_attribute dev_attr_inquiry = {
 853         .attr = {
 854                 .name = "inquiry",
 855                 .mode = S_IRUGO,
 856         },
 857         .size = 0,
 858         .read = show_inquiry,
 859 };
 860
 861 static ssize_t
 862 show_iostat_counterbits(struct device *dev, struct device_attribute *attr,
 863                         char *buf)
 864 {
 865         return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
 866 }
 867
 868 static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
 869
 870 #define show_sdev_iostat(field)                                         \
 871 static ssize_t                                                          \
 872 show_iostat_##field(struct device *dev, struct device_attribute *attr,  \
 873                     char *buf)                                          \
 874 {                                                                       \
 875         struct scsi_device *sdev = to_scsi_device(dev);                 \
 876         unsigned long long count = atomic_read(&sdev->field);           \
 877         return snprintf(buf, 20, "0x%llx\n", count);                    \
 878 }                                                                       \
 879 static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
 880
 881 show_sdev_iostat(iorequest_cnt);
 882 show_sdev_iostat(iodone_cnt);
 883 show_sdev_iostat(ioerr_cnt);
 884
 885 static ssize_t
 886 sdev_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
 887 {
 888         struct scsi_device *sdev;
 889         sdev = to_scsi_device(dev);
 890         return snprintf (buf, 20, SCSI_DEVICE_MODALIAS_FMT "\n", sdev->type);
 891 }
 892 static DEVICE_ATTR(modalias, S_IRUGO, sdev_show_modalias, NULL);
 893
 894 #define DECLARE_EVT_SHOW(name, Cap_name)                                \
 895 static ssize_t                                                          \
 896 sdev_show_evt_##name(struct device *dev, struct device_attribute *attr, \
 897                      char *buf)                                         \
 898 {                                                                       \
 899         struct scsi_device *sdev = to_scsi_device(dev);                 \
 900         int val = test_bit(SDEV_EVT_##Cap_name, sdev->supported_events);\
 901         return snprintf(buf, 20, "%d\n", val);                          \
 902 }
 903
 904 #define DECLARE_EVT_STORE(name, Cap_name)                               \
 905 static ssize_t                                                          \
 906 sdev_store_evt_##name(struct device *dev, struct device_attribute *attr,\
 907                       const char *buf, size_t count)                    \
 908 {                                                                       \
 909         struct scsi_device *sdev = to_scsi_device(dev);                 \
 910         int val = simple_strtoul(buf, NULL, 0);                         \
 911         if (val == 0)                                                   \
 912                 clear_bit(SDEV_EVT_##Cap_name, sdev->supported_events); \
 913         else if (val == 1)                                              \
 914                 set_bit(SDEV_EVT_##Cap_name, sdev->supported_events);   \
 915         else                                                            \
 916                 return -EINVAL;                                         \
 917         return count;                                                   \
 918 }
 919
 920 #define DECLARE_EVT(name, Cap_name)                                     \
 921         DECLARE_EVT_SHOW(name, Cap_name)                                \
 922         DECLARE_EVT_STORE(name, Cap_name)                               \
 923         static DEVICE_ATTR(evt_##name, S_IRUGO, sdev_show_evt_##name,   \
 924                            sdev_store_evt_##name);
 925 #define REF_EVT(name) &dev_attr_evt_##name.attr
 926
 927 DECLARE_EVT(media_change, MEDIA_CHANGE)
 928 DECLARE_EVT(inquiry_change_reported, INQUIRY_CHANGE_REPORTED)
 929 DECLARE_EVT(capacity_change_reported, CAPACITY_CHANGE_REPORTED)
 930 DECLARE_EVT(soft_threshold_reached, SOFT_THRESHOLD_REACHED_REPORTED)
 931 DECLARE_EVT(mode_parameter_change_reported, MODE_PARAMETER_CHANGE_REPORTED)
 932 DECLARE_EVT(lun_change_reported, LUN_CHANGE_REPORTED)
 933
 934 static ssize_t
 935 sdev_store_queue_depth(struct device *dev, struct device_attribute *attr,
 936                        const char *buf, size_t count)
 937 {
 938         int depth, retval;
 939         struct scsi_device *sdev = to_scsi_device(dev);
 940         struct scsi_host_template *sht = sdev->host->hostt;
 941
 942         if (!sht->change_queue_depth)
 943                 return -EINVAL;
 944
 945         depth = simple_strtoul(buf, NULL, 0);
 946
 947         if (depth < 1 || depth > sdev->host->can_queue)
 948                 return -EINVAL;
 949
 950         retval = sht->change_queue_depth(sdev, depth);
 951         if (retval < 0)
 952                 return retval;
 953
 954         sdev->max_queue_depth = sdev->queue_depth;
 955
 956         return count;
 957 }
 958 sdev_show_function(queue_depth, "%d\n");
 959
 960 static DEVICE_ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
 961                    sdev_store_queue_depth);
 962
 963 static ssize_t
 964 sdev_show_wwid(struct device *dev, struct device_attribute *attr,
 965                     char *buf)
 966 {
 967         struct scsi_device *sdev = to_scsi_device(dev);
 968         ssize_t count;
 969
 970         count = scsi_vpd_lun_id(sdev, buf, PAGE_SIZE);
 971         if (count > 0) {
 972                 buf[count] = '\n';
 973                 count++;
 974         }
 975         return count;
 976 }
 977 static DEVICE_ATTR(wwid, S_IRUGO, sdev_show_wwid, NULL);
 978
 979 #ifdef CONFIG_SCSI_DH
 980 static ssize_t
 981 sdev_show_dh_state(struct device *dev, struct device_attribute *attr,
 982                    char *buf)
 983 {
 984         struct scsi_device *sdev = to_scsi_device(dev);
 985
 986         if (!sdev->handler)
 987                 return snprintf(buf, 20, "detached\n");
 988
 989         return snprintf(buf, 20, "%s\n", sdev->handler->name);
 990 }
 991
 992 static ssize_t
 993 sdev_store_dh_state(struct device *dev, struct device_attribute *attr,
 994                     const char *buf, size_t count)
 995 {
 996         struct scsi_device *sdev = to_scsi_device(dev);
 997         int err = -EINVAL;
 998
 999         if (sdev->sdev_state == SDEV_CANCEL ||
1000             sdev->sdev_state == SDEV_DEL)
1001                 return -ENODEV;
1002
1003         if (!sdev->handler) {
1004                 /*
1005                  * Attach to a device handler
1006                  */
1007                 err = scsi_dh_attach(sdev->request_queue, buf);
1008         } else if (!strncmp(buf, "activate", 8)) {
1009                 /*
1010                  * Activate a device handler
1011                  */
1012                 if (sdev->handler->activate)
1013                         err = sdev->handler->activate(sdev, NULL, NULL);
1014                 else
1015                         err = 0;
1016         } else if (!strncmp(buf, "detach", 6)) {
1017                 /*
1018                  * Detach from a device handler
1019                  */
1020                 sdev_printk(KERN_WARNING, sdev,
1021                             "can't detach handler %s.\n",
1022                             sdev->handler->name);
1023                 err = -EINVAL;
1024         }
1025
1026         return err < 0 ? err : count;
1027 }
1028
1029 static DEVICE_ATTR(dh_state, S_IRUGO | S_IWUSR, sdev_show_dh_state,
1030                    sdev_store_dh_state);
1031
1032 static ssize_t
1033 sdev_show_access_state(struct device *dev,
1034                        struct device_attribute *attr,
1035                        char *buf)
1036 {
1037         struct scsi_device *sdev = to_scsi_device(dev);
1038         unsigned char access_state;
1039         const char *access_state_name;
1040
1041         if (!sdev->handler)
1042                 return -EINVAL;
1043
1044         access_state = (sdev->access_state & SCSI_ACCESS_STATE_MASK);
1045         access_state_name = scsi_access_state_name(access_state);
1046
1047         return sprintf(buf, "%s\n",
1048                        access_state_name ? access_state_name : "unknown");
1049 }
1050 static DEVICE_ATTR(access_state, S_IRUGO, sdev_show_access_state, NULL);
1051
1052 static ssize_t
1053 sdev_show_preferred_path(struct device *dev,
1054                          struct device_attribute *attr,
1055                          char *buf)
1056 {
1057         struct scsi_device *sdev = to_scsi_device(dev);
1058
1059         if (!sdev->handler)
1060                 return -EINVAL;
1061
1062         if (sdev->access_state & SCSI_ACCESS_STATE_PREFERRED)
1063                 return sprintf(buf, "1\n");
1064         else
1065                 return sprintf(buf, "0\n");
1066 }
1067 static DEVICE_ATTR(preferred_path, S_IRUGO, sdev_show_preferred_path, NULL);
1068 #endif
1069
1070 static ssize_t
1071 sdev_show_queue_ramp_up_period(struct device *dev,
1072                                struct device_attribute *attr,
1073                                char *buf)
1074 {
1075         struct scsi_device *sdev;
1076         sdev = to_scsi_device(dev);
1077         return snprintf(buf, 20, "%u\n",
1078                         jiffies_to_msecs(sdev->queue_ramp_up_period));
1079 }
1080
1081 static ssize_t
1082 sdev_store_queue_ramp_up_period(struct device *dev,
1083                                 struct device_attribute *attr,
1084                                 const char *buf, size_t count)
1085 {
1086         struct scsi_device *sdev = to_scsi_device(dev);
1087         unsigned int period;
1088
1089         if (kstrtouint(buf, 10, &period))
1090                 return -EINVAL;
1091
1092         sdev->queue_ramp_up_period = msecs_to_jiffies(period);
1093         return count;
1094 }
1095
1096 static DEVICE_ATTR(queue_ramp_up_period, S_IRUGO | S_IWUSR,
1097                    sdev_show_queue_ramp_up_period,
1098                    sdev_store_queue_ramp_up_period);
1099
1100 static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj,
1101                                          struct attribute *attr, int i)
1102 {
1103         struct device *dev = container_of(kobj, struct device, kobj);
1104         struct scsi_device *sdev = to_scsi_device(dev);
1105
1106
1107         if (attr == &dev_attr_queue_depth.attr &&
1108             !sdev->host->hostt->change_queue_depth)
1109                 return S_IRUGO;
1110
1111         if (attr == &dev_attr_queue_ramp_up_period.attr &&
1112             !sdev->host->hostt->change_queue_depth)
1113                 return 0;
1114
1115 #ifdef CONFIG_SCSI_DH
1116         if (attr == &dev_attr_access_state.attr &&
1117             !sdev->handler)
1118                 return 0;
1119         if (attr == &dev_attr_preferred_path.attr &&
1120             !sdev->handler)
1121                 return 0;
1122 #endif
1123         return attr->mode;
1124 }
1125
1126 static umode_t scsi_sdev_bin_attr_is_visible(struct kobject *kobj,
1127                                              struct bin_attribute *attr, int i)
1128 {
1129         struct device *dev = container_of(kobj, struct device, kobj);
1130         struct scsi_device *sdev = to_scsi_device(dev);
1131
1132
1133         if (attr == &dev_attr_vpd_pg80 && !sdev->vpd_pg80)
1134                 return 0;
1135
1136         if (attr == &dev_attr_vpd_pg83 && !sdev->vpd_pg83)
1137                 return 0;
1138
1139         return S_IRUGO;
1140 }
1141
1142 /* Default template for device attributes.  May NOT be modified */
1143 static struct attribute *scsi_sdev_attrs[] = {
1144         &dev_attr_device_blocked.attr,
1145         &dev_attr_type.attr,
1146         &dev_attr_scsi_level.attr,
1147         &dev_attr_device_busy.attr,
1148         &dev_attr_vendor.attr,
1149         &dev_attr_model.attr,
1150         &dev_attr_rev.attr,
1151         &dev_attr_rescan.attr,
1152         &dev_attr_delete.attr,
1153         &dev_attr_state.attr,
1154         &dev_attr_timeout.attr,
1155         &dev_attr_eh_timeout.attr,
1156         &dev_attr_iocounterbits.attr,
1157         &dev_attr_iorequest_cnt.attr,
1158         &dev_attr_iodone_cnt.attr,
1159         &dev_attr_ioerr_cnt.attr,
1160         &dev_attr_modalias.attr,
1161         &dev_attr_queue_depth.attr,
1162         &dev_attr_queue_type.attr,
1163         &dev_attr_wwid.attr,
1164 #ifdef CONFIG_SCSI_DH
1165         &dev_attr_dh_state.attr,
1166         &dev_attr_access_state.attr,
1167         &dev_attr_preferred_path.attr,
1168 #endif
1169         &dev_attr_queue_ramp_up_period.attr,
1170         REF_EVT(media_change),
1171         REF_EVT(inquiry_change_reported),
1172         REF_EVT(capacity_change_reported),
1173         REF_EVT(soft_threshold_reached),
1174         REF_EVT(mode_parameter_change_reported),
1175         REF_EVT(lun_change_reported),
1176         NULL
1177 };
1178
1179 static struct bin_attribute *scsi_sdev_bin_attrs[] = {
1180         &dev_attr_vpd_pg83,
1181         &dev_attr_vpd_pg80,
1182         &dev_attr_inquiry,
1183         NULL
1184 };
1185 static struct attribute_group scsi_sdev_attr_group = {
1186         .attrs =        scsi_sdev_attrs,
1187         .bin_attrs =    scsi_sdev_bin_attrs,
1188         .is_visible =   scsi_sdev_attr_is_visible,
1189         .is_bin_visible = scsi_sdev_bin_attr_is_visible,
1190 };
1191
1192 static const struct attribute_group *scsi_sdev_attr_groups[] = {
1193         &scsi_sdev_attr_group,
1194         NULL
1195 };
1196
1197 static int scsi_target_add(struct scsi_target *starget)
1198 {
1199         int error;
1200
1201         if (starget->state != STARGET_CREATED)
1202                 return 0;
1203
1204         error = device_add(&starget->dev);
1205         if (error) {
1206                 dev_err(&starget->dev, "target device_add failed, error %d\n", error);
1207                 return error;
1208         }
1209         transport_add_device(&starget->dev);
1210         starget->state = STARGET_RUNNING;
1211
1212         pm_runtime_set_active(&starget->dev);
1213         pm_runtime_enable(&starget->dev);
1214         device_enable_async_suspend(&starget->dev);
1215
1216         return 0;
1217 }
1218
1219 /**
1220  * scsi_sysfs_add_sdev - add scsi device to sysfs
1221  * @sdev:       scsi_device to add
1222  *
1223  * Return value:
1224  *      0 on Success / non-zero on Failure
1225  **/
1226 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
1227 {
1228         int error, i;
1229         struct request_queue *rq = sdev->request_queue;
1230         struct scsi_target *starget = sdev->sdev_target;
1231
1232         error = scsi_target_add(starget);
1233         if (error)
1234                 return error;
1235
1236         transport_configure_device(&starget->dev);
1237
1238         device_enable_async_suspend(&sdev->sdev_gendev);
1239         scsi_autopm_get_target(starget);
1240         pm_runtime_set_active(&sdev->sdev_gendev);
1241         pm_runtime_forbid(&sdev->sdev_gendev);
1242         pm_runtime_enable(&sdev->sdev_gendev);
1243         scsi_autopm_put_target(starget);
1244
1245         scsi_autopm_get_device(sdev);
1246
1247         error = scsi_dh_add_device(sdev);
1248         if (error)
1249                 /*
1250                  * device_handler is optional, so any error can be ignored
1251                  */
1252                 sdev_printk(KERN_INFO, sdev,
1253                                 "failed to add device handler: %d\n", error);
1254
1255         error = device_add(&sdev->sdev_gendev);
1256         if (error) {
1257                 sdev_printk(KERN_INFO, sdev,
1258                                 "failed to add device: %d\n", error);
1259                 scsi_dh_remove_device(sdev);
1260                 return error;
1261         }
1262
1263         device_enable_async_suspend(&sdev->sdev_dev);
1264         error = device_add(&sdev->sdev_dev);
1265         if (error) {
1266                 sdev_printk(KERN_INFO, sdev,
1267                                 "failed to add class device: %d\n", error);
1268                 scsi_dh_remove_device(sdev);
1269                 device_del(&sdev->sdev_gendev);
1270                 return error;
1271         }
1272         transport_add_device(&sdev->sdev_gendev);
1273         sdev->is_visible = 1;
1274
1275         error = bsg_register_queue(rq, &sdev->sdev_gendev, NULL, NULL);
1276
1277         if (error)
1278                 /* we're treating error on bsg register as non-fatal,
1279                  * so pretend nothing went wrong */
1280                 sdev_printk(KERN_INFO, sdev,
1281                             "Failed to register bsg queue, errno=%d\n", error);
1282
1283         /* add additional host specific attributes */
1284         if (sdev->host->hostt->sdev_attrs) {
1285                 for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
1286                         error = device_create_file(&sdev->sdev_gendev,
1287                                         sdev->host->hostt->sdev_attrs[i]);
1288                         if (error)
1289                                 return error;
1290                 }
1291         }
1292
1293         scsi_autopm_put_device(sdev);
1294         return error;
1295 }
1296
1297 void __scsi_remove_device(struct scsi_device *sdev)
1298 {
1299         struct device *dev = &sdev->sdev_gendev;
1300
1301         /*
1302          * This cleanup path is not reentrant and while it is impossible
1303          * to get a new reference with scsi_device_get() someone can still
1304          * hold a previously acquired one.
1305          */
1306         if (sdev->sdev_state == SDEV_DEL)
1307                 return;
1308
1309         if (sdev->is_visible) {
1310                 if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
1311                         return;
1312
1313                 bsg_unregister_queue(sdev->request_queue);
1314                 device_unregister(&sdev->sdev_dev);
1315                 transport_remove_device(dev);
1316                 scsi_dh_remove_device(sdev);
1317                 device_del(dev);
1318         } else
1319                 put_device(&sdev->sdev_dev);
1320
1321         /*
1322          * Stop accepting new requests and wait until all queuecommand() and
1323          * scsi_run_queue() invocations have finished before tearing down the
1324          * device.
1325          */
1326         scsi_device_set_state(sdev, SDEV_DEL);
1327         blk_cleanup_queue(sdev->request_queue);
1328         cancel_work_sync(&sdev->requeue_work);
1329
1330         if (sdev->host->hostt->slave_destroy)
1331                 sdev->host->hostt->slave_destroy(sdev);
1332         transport_destroy_device(dev);
1333
1334         /*
1335          * Paired with the kref_get() in scsi_sysfs_initialize().  We have
1336          * remoed sysfs visibility from the device, so make the target
1337          * invisible if this was the last device underneath it.
1338          */
1339         scsi_target_reap(scsi_target(sdev));
1340
1341         put_device(dev);
1342 }
1343
1344 /**
1345  * scsi_remove_device - unregister a device from the scsi bus
1346  * @sdev:       scsi_device to unregister
1347  **/
1348 void scsi_remove_device(struct scsi_device *sdev)
1349 {
1350         struct Scsi_Host *shost = sdev->host;
1351
1352         mutex_lock(&shost->scan_mutex);
1353         __scsi_remove_device(sdev);
1354         mutex_unlock(&shost->scan_mutex);
1355 }
1356 EXPORT_SYMBOL(scsi_remove_device);
1357
1358 static void __scsi_remove_target(struct scsi_target *starget)
1359 {
1360         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1361         unsigned long flags;
1362         struct scsi_device *sdev;
1363
1364         spin_lock_irqsave(shost->host_lock, flags);
1365  restart:
1366         list_for_each_entry(sdev, &shost->__devices, siblings) {
1367                 if (sdev->channel != starget->channel ||
1368                     sdev->id != starget->id ||
1369                     scsi_device_get(sdev))
1370                         continue;
1371                 spin_unlock_irqrestore(shost->host_lock, flags);
1372                 scsi_remove_device(sdev);
1373                 scsi_device_put(sdev);
1374                 spin_lock_irqsave(shost->host_lock, flags);
1375                 goto restart;
1376         }
1377         spin_unlock_irqrestore(shost->host_lock, flags);
1378 }
1379
1380 /**
1381  * scsi_remove_target - try to remove a target and all its devices
1382  * @dev: generic starget or parent of generic stargets to be removed
1383  *
1384  * Note: This is slightly racy.  It is possible that if the user
1385  * requests the addition of another device then the target won't be
1386  * removed.
1387  */
1388 void scsi_remove_target(struct device *dev)
1389 {
1390         struct Scsi_Host *shost = dev_to_shost(dev->parent);
1391         struct scsi_target *starget;
1392         unsigned long flags;
1393
1394 restart:
1395         spin_lock_irqsave(shost->host_lock, flags);
1396         list_for_each_entry(starget, &shost->__targets, siblings) {
1397                 if (starget->state == STARGET_DEL ||
1398                     starget->state == STARGET_REMOVE ||
1399                     starget->state == STARGET_CREATED_REMOVE)
1400                         continue;
1401                 if (starget->dev.parent == dev || &starget->dev == dev) {
1402                         kref_get(&starget->reap_ref);
1403                         if (starget->state == STARGET_CREATED)
1404                                 starget->state = STARGET_CREATED_REMOVE;
1405                         else
1406                                 starget->state = STARGET_REMOVE;
1407                         spin_unlock_irqrestore(shost->host_lock, flags);
1408                         __scsi_remove_target(starget);
1409                         scsi_target_reap(starget);
1410                         goto restart;
1411                 }
1412         }
1413         spin_unlock_irqrestore(shost->host_lock, flags);
1414 }
1415 EXPORT_SYMBOL(scsi_remove_target);
1416
1417 int scsi_register_driver(struct device_driver *drv)
1418 {
1419         drv->bus = &scsi_bus_type;
1420
1421         return driver_register(drv);
1422 }
1423 EXPORT_SYMBOL(scsi_register_driver);
1424
1425 int scsi_register_interface(struct class_interface *intf)
1426 {
1427         intf->class = &sdev_class;
1428
1429         return class_interface_register(intf);
1430 }
1431 EXPORT_SYMBOL(scsi_register_interface);
1432
1433 /**
1434  * scsi_sysfs_add_host - add scsi host to subsystem
1435  * @shost:     scsi host struct to add to subsystem
1436  **/
1437 int scsi_sysfs_add_host(struct Scsi_Host *shost)
1438 {
1439         int error, i;
1440
1441         /* add host specific attributes */
1442         if (shost->hostt->shost_attrs) {
1443                 for (i = 0; shost->hostt->shost_attrs[i]; i++) {
1444                         error = device_create_file(&shost->shost_dev,
1445                                         shost->hostt->shost_attrs[i]);
1446                         if (error)
1447                                 return error;
1448                 }
1449         }
1450
1451         transport_register_device(&shost->shost_gendev);
1452         transport_configure_device(&shost->shost_gendev);
1453         return 0;
1454 }
1455
1456 static struct device_type scsi_dev_type = {
1457         .name =         "scsi_device",
1458         .release =      scsi_device_dev_release,
1459         .groups =       scsi_sdev_attr_groups,
1460 };
1461
1462 void scsi_sysfs_device_initialize(struct scsi_device *sdev)
1463 {
1464         unsigned long flags;
1465         struct Scsi_Host *shost = sdev->host;
1466         struct scsi_target  *starget = sdev->sdev_target;
1467
1468         device_initialize(&sdev->sdev_gendev);
1469         sdev->sdev_gendev.bus = &scsi_bus_type;
1470         sdev->sdev_gendev.type = &scsi_dev_type;
1471         dev_set_name(&sdev->sdev_gendev, "%d:%d:%d:%llu",
1472                      sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
1473
1474         device_initialize(&sdev->sdev_dev);
1475         sdev->sdev_dev.parent = get_device(&sdev->sdev_gendev);
1476         sdev->sdev_dev.class = &sdev_class;
1477         dev_set_name(&sdev->sdev_dev, "%d:%d:%d:%llu",
1478                      sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
1479         /*
1480          * Get a default scsi_level from the target (derived from sibling
1481          * devices).  This is the best we can do for guessing how to set
1482          * sdev->lun_in_cdb for the initial INQUIRY command.  For LUN 0 the
1483          * setting doesn't matter, because all the bits are zero anyway.
1484          * But it does matter for higher LUNs.
1485          */
1486         sdev->scsi_level = starget->scsi_level;
1487         if (sdev->scsi_level <= SCSI_2 &&
1488                         sdev->scsi_level != SCSI_UNKNOWN &&
1489                         !shost->no_scsi2_lun_in_cdb)
1490                 sdev->lun_in_cdb = 1;
1491
1492         transport_setup_device(&sdev->sdev_gendev);
1493         spin_lock_irqsave(shost->host_lock, flags);
1494         list_add_tail(&sdev->same_target_siblings, &starget->devices);
1495         list_add_tail(&sdev->siblings, &shost->__devices);
1496         spin_unlock_irqrestore(shost->host_lock, flags);
1497         /*
1498          * device can now only be removed via __scsi_remove_device() so hold
1499          * the target.  Target will be held in CREATED state until something
1500          * beneath it becomes visible (in which case it moves to RUNNING)
1501          */
1502         kref_get(&starget->reap_ref);
1503 }
1504
1505 int scsi_is_sdev_device(const struct device *dev)
1506 {
1507         return dev->type == &scsi_dev_type;
1508 }
1509 EXPORT_SYMBOL(scsi_is_sdev_device);
1510
1511 /* A blank transport template that is used in drivers that don't
1512  * yet implement Transport Attributes */
1513 struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };