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/init.h>
  11 #include <linux/blkdev.h>
  12 #include <linux/device.h>
  13
  14 #include <scsi/scsi.h>
  15 #include <scsi/scsi_device.h>
  16 #include <scsi/scsi_host.h>
  17 #include <scsi/scsi_tcq.h>
  18 #include <scsi/scsi_transport.h>
  19 #include <scsi/scsi_driver.h>
  20
  21 #include "scsi_priv.h"
  22 #include "scsi_logging.h"
  23
  24 static const struct {
  25         enum scsi_device_state  value;
  26         char                    *name;
  27 } sdev_states[] = {
  28         { SDEV_CREATED, "created" },
  29         { SDEV_RUNNING, "running" },
  30         { SDEV_CANCEL, "cancel" },
  31         { SDEV_DEL, "deleted" },
  32         { SDEV_QUIESCE, "quiesce" },
  33         { SDEV_OFFLINE, "offline" },
  34         { SDEV_BLOCK,   "blocked" },
  35 };
  36
  37 const char *scsi_device_state_name(enum scsi_device_state state)
  38 {
  39         int i;
  40         char *name = NULL;
  41
  42         for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
  43                 if (sdev_states[i].value == state) {
  44                         name = sdev_states[i].name;
  45                         break;
  46                 }
  47         }
  48         return name;
  49 }
  50
  51 static const struct {
  52         enum scsi_host_state    value;
  53         char                    *name;
  54 } shost_states[] = {
  55         { SHOST_CREATED, "created" },
  56         { SHOST_RUNNING, "running" },
  57         { SHOST_CANCEL, "cancel" },
  58         { SHOST_DEL, "deleted" },
  59         { SHOST_RECOVERY, "recovery" },
  60         { SHOST_CANCEL_RECOVERY, "cancel/recovery" },
  61         { SHOST_DEL_RECOVERY, "deleted/recovery", },
  62 };
  63 const char *scsi_host_state_name(enum scsi_host_state state)
  64 {
  65         int i;
  66         char *name = NULL;
  67
  68         for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
  69                 if (shost_states[i].value == state) {
  70                         name = shost_states[i].name;
  71                         break;
  72                 }
  73         }
  74         return name;
  75 }
  76
  77 static int check_set(unsigned int *val, char *src)
  78 {
  79         char *last;
  80
  81         if (strncmp(src, "-", 20) == 0) {
  82                 *val = SCAN_WILD_CARD;
  83         } else {
  84                 /*
  85                  * Doesn't check for int overflow
  86                  */
  87                 *val = simple_strtoul(src, &last, 0);
  88                 if (*last != '\0')
  89                         return 1;
  90         }
  91         return 0;
  92 }
  93
  94 static int scsi_scan(struct Scsi_Host *shost, const char *str)
  95 {
  96         char s1[15], s2[15], s3[15], junk;
  97         unsigned int channel, id, lun;
  98         int res;
  99
 100         res = sscanf(str, "%10s %10s %10s %c", s1, s2, s3, &junk);
 101         if (res != 3)
 102                 return -EINVAL;
 103         if (check_set(&channel, s1))
 104                 return -EINVAL;
 105         if (check_set(&id, s2))
 106                 return -EINVAL;
 107         if (check_set(&lun, s3))
 108                 return -EINVAL;
 109         if (shost->transportt->user_scan)
 110                 res = shost->transportt->user_scan(shost, channel, id, lun);
 111         else
 112                 res = scsi_scan_host_selected(shost, channel, id, lun, 1);
 113         return res;
 114 }
 115
 116 /*
 117  * shost_show_function: macro to create an attr function that can be used to
 118  * show a non-bit field.
 119  */
 120 #define shost_show_function(name, field, format_string)                 \
 121 static ssize_t                                                          \
 122 show_##name (struct class_device *class_dev, char *buf)                 \
 123 {                                                                       \
 124         struct Scsi_Host *shost = class_to_shost(class_dev);            \
 125         return snprintf (buf, 20, format_string, shost->field);         \
 126 }
 127
 128 /*
 129  * shost_rd_attr: macro to create a function and attribute variable for a
 130  * read only field.
 131  */
 132 #define shost_rd_attr2(name, field, format_string)                      \
 133         shost_show_function(name, field, format_string)                 \
 134 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
 135
 136 #define shost_rd_attr(field, format_string) \
 137 shost_rd_attr2(field, field, format_string)
 138
 139 /*
 140  * Create the actual show/store functions and data structures.
 141  */
 142
 143 static ssize_t store_scan(struct class_device *class_dev, const char *buf,
 144                           size_t count)
 145 {
 146         struct Scsi_Host *shost = class_to_shost(class_dev);
 147         int res;
 148
 149         res = scsi_scan(shost, buf);
 150         if (res == 0)
 151                 res = count;
 152         return res;
 153 };
 154 static CLASS_DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
 155
 156 static ssize_t
 157 store_shost_state(struct class_device *class_dev, const char *buf, size_t count)
 158 {
 159         int i;
 160         struct Scsi_Host *shost = class_to_shost(class_dev);
 161         enum scsi_host_state state = 0;
 162
 163         for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
 164                 const int len = strlen(shost_states[i].name);
 165                 if (strncmp(shost_states[i].name, buf, len) == 0 &&
 166                    buf[len] == '\n') {
 167                         state = shost_states[i].value;
 168                         break;
 169                 }
 170         }
 171         if (!state)
 172                 return -EINVAL;
 173
 174         if (scsi_host_set_state(shost, state))
 175                 return -EINVAL;
 176         return count;
 177 }
 178
 179 static ssize_t
 180 show_shost_state(struct class_device *class_dev, char *buf)
 181 {
 182         struct Scsi_Host *shost = class_to_shost(class_dev);
 183         const char *name = scsi_host_state_name(shost->shost_state);
 184
 185         if (!name)
 186                 return -EINVAL;
 187
 188         return snprintf(buf, 20, "%s\n", name);
 189 }
 190
 191 static CLASS_DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_shost_state, store_shost_state);
 192
 193 static ssize_t
 194 show_shost_mode(unsigned int mode, char *buf)
 195 {
 196         ssize_t len = 0;
 197
 198         if (mode & MODE_INITIATOR)
 199                 len = sprintf(buf, "%s", "Initiator");
 200
 201         if (mode & MODE_TARGET)
 202                 len += sprintf(buf + len, "%s%s", len ? ", " : "", "Target");
 203
 204         len += sprintf(buf + len, "\n");
 205
 206         return len;
 207 }
 208
 209 static ssize_t show_shost_supported_mode(struct class_device *class_dev, char *buf)
 210 {
 211         struct Scsi_Host *shost = class_to_shost(class_dev);
 212
 213         if (shost->hostt->supported_mode == MODE_UNKNOWN)
 214                 return snprintf(buf, 20, "unknown\n");
 215         else
 216                 return show_shost_mode(shost->hostt->supported_mode, buf);
 217 }
 218
 219 static CLASS_DEVICE_ATTR(supported_mode, S_IRUGO | S_IWUSR, show_shost_supported_mode, NULL);
 220
 221 static ssize_t show_shost_active_mode(struct class_device *class_dev, char *buf)
 222 {
 223         struct Scsi_Host *shost = class_to_shost(class_dev);
 224
 225         if (shost->active_mode == MODE_UNKNOWN)
 226                 return snprintf(buf, 20, "unknown\n");
 227         else
 228                 return show_shost_mode(shost->active_mode, buf);
 229 }
 230
 231 static CLASS_DEVICE_ATTR(active_mode, S_IRUGO | S_IWUSR, show_shost_active_mode, NULL);
 232
 233 shost_rd_attr(unique_id, "%u\n");
 234 shost_rd_attr(host_busy, "%hu\n");
 235 shost_rd_attr(cmd_per_lun, "%hd\n");
 236 shost_rd_attr(can_queue, "%hd\n");
 237 shost_rd_attr(sg_tablesize, "%hu\n");
 238 shost_rd_attr(unchecked_isa_dma, "%d\n");
 239 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
 240
 241 static struct class_device_attribute *scsi_sysfs_shost_attrs[] = {
 242         &class_device_attr_unique_id,
 243         &class_device_attr_host_busy,
 244         &class_device_attr_cmd_per_lun,
 245         &class_device_attr_can_queue,
 246         &class_device_attr_sg_tablesize,
 247         &class_device_attr_unchecked_isa_dma,
 248         &class_device_attr_proc_name,
 249         &class_device_attr_scan,
 250         &class_device_attr_state,
 251         &class_device_attr_supported_mode,
 252         &class_device_attr_active_mode,
 253         NULL
 254 };
 255
 256 static void scsi_device_cls_release(struct class_device *class_dev)
 257 {
 258         struct scsi_device *sdev;
 259
 260         sdev = class_to_sdev(class_dev);
 261         put_device(&sdev->sdev_gendev);
 262 }
 263
 264 static void scsi_device_dev_release_usercontext(struct work_struct *work)
 265 {
 266         struct scsi_device *sdev;
 267         struct device *parent;
 268         struct scsi_target *starget;
 269         unsigned long flags;
 270
 271         sdev = container_of(work, struct scsi_device, ew.work);
 272
 273         parent = sdev->sdev_gendev.parent;
 274         starget = to_scsi_target(parent);
 275
 276         spin_lock_irqsave(sdev->host->host_lock, flags);
 277         starget->reap_ref++;
 278         list_del(&sdev->siblings);
 279         list_del(&sdev->same_target_siblings);
 280         list_del(&sdev->starved_entry);
 281         spin_unlock_irqrestore(sdev->host->host_lock, flags);
 282
 283         if (sdev->request_queue) {
 284                 sdev->request_queue->queuedata = NULL;
 285                 /* user context needed to free queue */
 286                 scsi_free_queue(sdev->request_queue);
 287                 /* temporary expedient, try to catch use of queue lock
 288                  * after free of sdev */
 289                 sdev->request_queue = NULL;
 290         }
 291
 292         scsi_target_reap(scsi_target(sdev));
 293
 294         kfree(sdev->inquiry);
 295         kfree(sdev);
 296
 297         if (parent)
 298                 put_device(parent);
 299 }
 300
 301 static void scsi_device_dev_release(struct device *dev)
 302 {
 303         struct scsi_device *sdp = to_scsi_device(dev);
 304         execute_in_process_context(scsi_device_dev_release_usercontext,
 305                                    &sdp->ew);
 306 }
 307
 308 static struct class sdev_class = {
 309         .name           = "scsi_device",
 310         .release        = scsi_device_cls_release,
 311 };
 312
 313 /* all probing is done in the individual ->probe routines */
 314 static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
 315 {
 316         struct scsi_device *sdp = to_scsi_device(dev);
 317         if (sdp->no_uld_attach)
 318                 return 0;
 319         return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
 320 }
 321
 322 static int scsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
 323 {
 324         struct scsi_device *sdev = to_scsi_device(dev);
 325
 326         add_uevent_var(env, "MODALIAS=" SCSI_DEVICE_MODALIAS_FMT, sdev->type);
 327         return 0;
 328 }
 329
 330 static int scsi_bus_suspend(struct device * dev, pm_message_t state)
 331 {
 332         struct device_driver *drv = dev->driver;
 333         struct scsi_device *sdev = to_scsi_device(dev);
 334         int err;
 335
 336         err = scsi_device_quiesce(sdev);
 337         if (err)
 338                 return err;
 339
 340         if (drv && drv->suspend) {
 341                 err = drv->suspend(dev, state);
 342                 if (err)
 343                         return err;
 344         }
 345
 346         return 0;
 347 }
 348
 349 static int scsi_bus_resume(struct device * dev)
 350 {
 351         struct device_driver *drv = dev->driver;
 352         struct scsi_device *sdev = to_scsi_device(dev);
 353         int err = 0;
 354
 355         if (drv && drv->resume)
 356                 err = drv->resume(dev);
 357
 358         scsi_device_resume(sdev);
 359
 360         return err;
 361 }
 362
 363 struct bus_type scsi_bus_type = {
 364         .name           = "scsi",
 365         .match          = scsi_bus_match,
 366         .uevent         = scsi_bus_uevent,
 367         .suspend        = scsi_bus_suspend,
 368         .resume         = scsi_bus_resume,
 369 };
 370
 371 int scsi_sysfs_register(void)
 372 {
 373         int error;
 374
 375         error = bus_register(&scsi_bus_type);
 376         if (!error) {
 377                 error = class_register(&sdev_class);
 378                 if (error)
 379                         bus_unregister(&scsi_bus_type);
 380         }
 381
 382         return error;
 383 }
 384
 385 void scsi_sysfs_unregister(void)
 386 {
 387         class_unregister(&sdev_class);
 388         bus_unregister(&scsi_bus_type);
 389 }
 390
 391 /*
 392  * sdev_show_function: macro to create an attr function that can be used to
 393  * show a non-bit field.
 394  */
 395 #define sdev_show_function(field, format_string)                                \
 396 static ssize_t                                                          \
 397 sdev_show_##field (struct device *dev, struct device_attribute *attr, char *buf)                                \
 398 {                                                                       \
 399         struct scsi_device *sdev;                                       \
 400         sdev = to_scsi_device(dev);                                     \
 401         return snprintf (buf, 20, format_string, sdev->field);          \
 402 }                                                                       \
 403
 404 /*
 405  * sdev_rd_attr: macro to create a function and attribute variable for a
 406  * read only field.
 407  */
 408 #define sdev_rd_attr(field, format_string)                              \
 409         sdev_show_function(field, format_string)                        \
 410 static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
 411
 412
 413 /*
 414  * sdev_rd_attr: create a function and attribute variable for a
 415  * read/write field.
 416  */
 417 #define sdev_rw_attr(field, format_string)                              \
 418         sdev_show_function(field, format_string)                                \
 419                                                                         \
 420 static ssize_t                                                          \
 421 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)   \
 422 {                                                                       \
 423         struct scsi_device *sdev;                                       \
 424         sdev = to_scsi_device(dev);                                     \
 425         snscanf (buf, 20, format_string, &sdev->field);                 \
 426         return count;                                                   \
 427 }                                                                       \
 428 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
 429
 430 /* Currently we don't export bit fields, but we might in future,
 431  * so leave this code in */
 432 #if 0
 433 /*
 434  * sdev_rd_attr: create a function and attribute variable for a
 435  * read/write bit field.
 436  */
 437 #define sdev_rw_attr_bit(field)                                         \
 438         sdev_show_function(field, "%d\n")                                       \
 439                                                                         \
 440 static ssize_t                                                          \
 441 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)   \
 442 {                                                                       \
 443         int ret;                                                        \
 444         struct scsi_device *sdev;                                       \
 445         ret = scsi_sdev_check_buf_bit(buf);                             \
 446         if (ret >= 0)   {                                               \
 447                 sdev = to_scsi_device(dev);                             \
 448                 sdev->field = ret;                                      \
 449                 ret = count;                                            \
 450         }                                                               \
 451         return ret;                                                     \
 452 }                                                                       \
 453 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
 454
 455 /*
 456  * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
 457  * else return -EINVAL.
 458  */
 459 static int scsi_sdev_check_buf_bit(const char *buf)
 460 {
 461         if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
 462                 if (buf[0] == '1')
 463                         return 1;
 464                 else if (buf[0] == '0')
 465                         return 0;
 466                 else
 467                         return -EINVAL;
 468         } else
 469                 return -EINVAL;
 470 }
 471 #endif
 472 /*
 473  * Create the actual show/store functions and data structures.
 474  */
 475 sdev_rd_attr (device_blocked, "%d\n");
 476 sdev_rd_attr (queue_depth, "%d\n");
 477 sdev_rd_attr (type, "%d\n");
 478 sdev_rd_attr (scsi_level, "%d\n");
 479 sdev_rd_attr (vendor, "%.8s\n");
 480 sdev_rd_attr (model, "%.16s\n");
 481 sdev_rd_attr (rev, "%.4s\n");
 482
 483 static ssize_t
 484 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
 485 {
 486         struct scsi_device *sdev;
 487         sdev = to_scsi_device(dev);
 488         return snprintf (buf, 20, "%d\n", sdev->timeout / HZ);
 489 }
 490
 491 static ssize_t
 492 sdev_store_timeout (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 493 {
 494         struct scsi_device *sdev;
 495         int timeout;
 496         sdev = to_scsi_device(dev);
 497         sscanf (buf, "%d\n", &timeout);
 498         sdev->timeout = timeout * HZ;
 499         return count;
 500 }
 501 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
 502
 503 static ssize_t
 504 store_rescan_field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 505 {
 506         scsi_rescan_device(dev);
 507         return count;
 508 }
 509 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
 510
 511 static void sdev_store_delete_callback(struct device *dev)
 512 {
 513         scsi_remove_device(to_scsi_device(dev));
 514 }
 515
 516 static ssize_t sdev_store_delete(struct device *dev, struct device_attribute *attr, const char *buf,
 517                                  size_t count)
 518 {
 519         int rc;
 520
 521         /* An attribute cannot be unregistered by one of its own methods,
 522          * so we have to use this roundabout approach.
 523          */
 524         rc = device_schedule_callback(dev, sdev_store_delete_callback);
 525         if (rc)
 526                 count = rc;
 527         return count;
 528 };
 529 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
 530
 531 static ssize_t
 532 store_state_field(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 533 {
 534         int i;
 535         struct scsi_device *sdev = to_scsi_device(dev);
 536         enum scsi_device_state state = 0;
 537
 538         for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
 539                 const int len = strlen(sdev_states[i].name);
 540                 if (strncmp(sdev_states[i].name, buf, len) == 0 &&
 541                    buf[len] == '\n') {
 542                         state = sdev_states[i].value;
 543                         break;
 544                 }
 545         }
 546         if (!state)
 547                 return -EINVAL;
 548
 549         if (scsi_device_set_state(sdev, state))
 550                 return -EINVAL;
 551         return count;
 552 }
 553
 554 static ssize_t
 555 show_state_field(struct device *dev, struct device_attribute *attr, char *buf)
 556 {
 557         struct scsi_device *sdev = to_scsi_device(dev);
 558         const char *name = scsi_device_state_name(sdev->sdev_state);
 559
 560         if (!name)
 561                 return -EINVAL;
 562
 563         return snprintf(buf, 20, "%s\n", name);
 564 }
 565
 566 static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
 567
 568 static ssize_t
 569 show_queue_type_field(struct device *dev, struct device_attribute *attr, char *buf)
 570 {
 571         struct scsi_device *sdev = to_scsi_device(dev);
 572         const char *name = "none";
 573
 574         if (sdev->ordered_tags)
 575                 name = "ordered";
 576         else if (sdev->simple_tags)
 577                 name = "simple";
 578
 579         return snprintf(buf, 20, "%s\n", name);
 580 }
 581
 582 static DEVICE_ATTR(queue_type, S_IRUGO, show_queue_type_field, NULL);
 583
 584 static ssize_t
 585 show_iostat_counterbits(struct device *dev, struct device_attribute *attr, char *buf)
 586 {
 587         return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
 588 }
 589
 590 static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
 591
 592 #define show_sdev_iostat(field)                                         \
 593 static ssize_t                                                          \
 594 show_iostat_##field(struct device *dev, struct device_attribute *attr, char *buf)                       \
 595 {                                                                       \
 596         struct scsi_device *sdev = to_scsi_device(dev);                 \
 597         unsigned long long count = atomic_read(&sdev->field);           \
 598         return snprintf(buf, 20, "0x%llx\n", count);                    \
 599 }                                                                       \
 600 static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
 601
 602 show_sdev_iostat(iorequest_cnt);
 603 show_sdev_iostat(iodone_cnt);
 604 show_sdev_iostat(ioerr_cnt);
 605
 606 static ssize_t
 607 sdev_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
 608 {
 609         struct scsi_device *sdev;
 610         sdev = to_scsi_device(dev);
 611         return snprintf (buf, 20, SCSI_DEVICE_MODALIAS_FMT "\n", sdev->type);
 612 }
 613 static DEVICE_ATTR(modalias, S_IRUGO, sdev_show_modalias, NULL);
 614
 615 /* Default template for device attributes.  May NOT be modified */
 616 static struct attribute *scsi_sdev_attrs[] = {
 617         &dev_attr_device_blocked.attr,
 618         &dev_attr_type.attr,
 619         &dev_attr_scsi_level.attr,
 620         &dev_attr_vendor.attr,
 621         &dev_attr_model.attr,
 622         &dev_attr_rev.attr,
 623         &dev_attr_rescan.attr,
 624         &dev_attr_delete.attr,
 625         &dev_attr_state.attr,
 626         &dev_attr_timeout.attr,
 627         &dev_attr_iocounterbits.attr,
 628         &dev_attr_iorequest_cnt.attr,
 629         &dev_attr_iodone_cnt.attr,
 630         &dev_attr_ioerr_cnt.attr,
 631         &dev_attr_modalias.attr,
 632         NULL
 633 };
 634
 635 static struct attribute_group scsi_sdev_attr_group = {
 636         .attrs =        scsi_sdev_attrs,
 637 };
 638
 639 static struct attribute_group *scsi_sdev_attr_groups[] = {
 640         &scsi_sdev_attr_group,
 641         NULL
 642 };
 643
 644 static ssize_t sdev_store_queue_depth_rw(struct device *dev, struct device_attribute *attr, const char *buf,
 645                                          size_t count)
 646 {
 647         int depth, retval;
 648         struct scsi_device *sdev = to_scsi_device(dev);
 649         struct scsi_host_template *sht = sdev->host->hostt;
 650
 651         if (!sht->change_queue_depth)
 652                 return -EINVAL;
 653
 654         depth = simple_strtoul(buf, NULL, 0);
 655
 656         if (depth < 1)
 657                 return -EINVAL;
 658
 659         retval = sht->change_queue_depth(sdev, depth);
 660         if (retval < 0)
 661                 return retval;
 662
 663         return count;
 664 }
 665
 666 static struct device_attribute sdev_attr_queue_depth_rw =
 667         __ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
 668                sdev_store_queue_depth_rw);
 669
 670 static ssize_t sdev_store_queue_type_rw(struct device *dev, struct device_attribute *attr, const char *buf,
 671                                         size_t count)
 672 {
 673         struct scsi_device *sdev = to_scsi_device(dev);
 674         struct scsi_host_template *sht = sdev->host->hostt;
 675         int tag_type = 0, retval;
 676         int prev_tag_type = scsi_get_tag_type(sdev);
 677
 678         if (!sdev->tagged_supported || !sht->change_queue_type)
 679                 return -EINVAL;
 680
 681         if (strncmp(buf, "ordered", 7) == 0)
 682                 tag_type = MSG_ORDERED_TAG;
 683         else if (strncmp(buf, "simple", 6) == 0)
 684                 tag_type = MSG_SIMPLE_TAG;
 685         else if (strncmp(buf, "none", 4) != 0)
 686                 return -EINVAL;
 687
 688         if (tag_type == prev_tag_type)
 689                 return count;
 690
 691         retval = sht->change_queue_type(sdev, tag_type);
 692         if (retval < 0)
 693                 return retval;
 694
 695         return count;
 696 }
 697
 698 static struct device_attribute sdev_attr_queue_type_rw =
 699         __ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
 700                sdev_store_queue_type_rw);
 701
 702 /**
 703  * scsi_sysfs_add_sdev - add scsi device to sysfs
 704  * @sdev:       scsi_device to add
 705  *
 706  * Return value:
 707  *      0 on Success / non-zero on Failure
 708  **/
 709 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
 710 {
 711         int error, i;
 712         struct request_queue *rq = sdev->request_queue;
 713
 714         if ((error = scsi_device_set_state(sdev, SDEV_RUNNING)) != 0)
 715                 return error;
 716
 717         error = device_add(&sdev->sdev_gendev);
 718         if (error) {
 719                 put_device(sdev->sdev_gendev.parent);
 720                 printk(KERN_INFO "error 1\n");
 721                 return error;
 722         }
 723         error = class_device_add(&sdev->sdev_classdev);
 724         if (error) {
 725                 printk(KERN_INFO "error 2\n");
 726                 goto clean_device;
 727         }
 728
 729         /* take a reference for the sdev_classdev; this is
 730          * released by the sdev_class .release */
 731         get_device(&sdev->sdev_gendev);
 732
 733         /* create queue files, which may be writable, depending on the host */
 734         if (sdev->host->hostt->change_queue_depth)
 735                 error = device_create_file(&sdev->sdev_gendev, &sdev_attr_queue_depth_rw);
 736         else
 737                 error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_depth);
 738         if (error) {
 739                 __scsi_remove_device(sdev);
 740                 goto out;
 741         }
 742         if (sdev->host->hostt->change_queue_type)
 743                 error = device_create_file(&sdev->sdev_gendev, &sdev_attr_queue_type_rw);
 744         else
 745                 error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_type);
 746         if (error) {
 747                 __scsi_remove_device(sdev);
 748                 goto out;
 749         }
 750
 751         error = bsg_register_queue(rq, &sdev->sdev_gendev, NULL);
 752
 753         if (error)
 754                 sdev_printk(KERN_INFO, sdev,
 755                             "Failed to register bsg queue, errno=%d\n", error);
 756
 757         /* we're treating error on bsg register as non-fatal, so pretend
 758          * nothing went wrong */
 759         error = 0;
 760
 761         /* add additional host specific attributes */
 762         if (sdev->host->hostt->sdev_attrs) {
 763                 for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
 764                         error = device_create_file(&sdev->sdev_gendev,
 765                                         sdev->host->hostt->sdev_attrs[i]);
 766                         if (error) {
 767                                 __scsi_remove_device(sdev);
 768                                 goto out;
 769                         }
 770                 }
 771         }
 772
 773         transport_add_device(&sdev->sdev_gendev);
 774  out:
 775         return error;
 776
 777  clean_device:
 778         scsi_device_set_state(sdev, SDEV_CANCEL);
 779
 780         device_del(&sdev->sdev_gendev);
 781         transport_destroy_device(&sdev->sdev_gendev);
 782         put_device(&sdev->sdev_gendev);
 783
 784         return error;
 785 }
 786
 787 void __scsi_remove_device(struct scsi_device *sdev)
 788 {
 789         struct device *dev = &sdev->sdev_gendev;
 790
 791         if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
 792                 return;
 793
 794         bsg_unregister_queue(sdev->request_queue);
 795         class_device_unregister(&sdev->sdev_classdev);
 796         transport_remove_device(dev);
 797         device_del(dev);
 798         scsi_device_set_state(sdev, SDEV_DEL);
 799         if (sdev->host->hostt->slave_destroy)
 800                 sdev->host->hostt->slave_destroy(sdev);
 801         transport_destroy_device(dev);
 802         put_device(dev);
 803 }
 804
 805 /**
 806  * scsi_remove_device - unregister a device from the scsi bus
 807  * @sdev:       scsi_device to unregister
 808  **/
 809 void scsi_remove_device(struct scsi_device *sdev)
 810 {
 811         struct Scsi_Host *shost = sdev->host;
 812
 813         mutex_lock(&shost->scan_mutex);
 814         __scsi_remove_device(sdev);
 815         mutex_unlock(&shost->scan_mutex);
 816 }
 817 EXPORT_SYMBOL(scsi_remove_device);
 818
 819 static void __scsi_remove_target(struct scsi_target *starget)
 820 {
 821         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 822         unsigned long flags;
 823         struct scsi_device *sdev;
 824
 825         spin_lock_irqsave(shost->host_lock, flags);
 826         starget->reap_ref++;
 827  restart:
 828         list_for_each_entry(sdev, &shost->__devices, siblings) {
 829                 if (sdev->channel != starget->channel ||
 830                     sdev->id != starget->id ||
 831                     sdev->sdev_state == SDEV_DEL)
 832                         continue;
 833                 spin_unlock_irqrestore(shost->host_lock, flags);
 834                 scsi_remove_device(sdev);
 835                 spin_lock_irqsave(shost->host_lock, flags);
 836                 goto restart;
 837         }
 838         spin_unlock_irqrestore(shost->host_lock, flags);
 839         scsi_target_reap(starget);
 840 }
 841
 842 static int __remove_child (struct device * dev, void * data)
 843 {
 844         if (scsi_is_target_device(dev))
 845                 __scsi_remove_target(to_scsi_target(dev));
 846         return 0;
 847 }
 848
 849 /**
 850  * scsi_remove_target - try to remove a target and all its devices
 851  * @dev: generic starget or parent of generic stargets to be removed
 852  *
 853  * Note: This is slightly racy.  It is possible that if the user
 854  * requests the addition of another device then the target won't be
 855  * removed.
 856  */
 857 void scsi_remove_target(struct device *dev)
 858 {
 859         struct device *rdev;
 860
 861         if (scsi_is_target_device(dev)) {
 862                 __scsi_remove_target(to_scsi_target(dev));
 863                 return;
 864         }
 865
 866         rdev = get_device(dev);
 867         device_for_each_child(dev, NULL, __remove_child);
 868         put_device(rdev);
 869 }
 870 EXPORT_SYMBOL(scsi_remove_target);
 871
 872 int scsi_register_driver(struct device_driver *drv)
 873 {
 874         drv->bus = &scsi_bus_type;
 875
 876         return driver_register(drv);
 877 }
 878 EXPORT_SYMBOL(scsi_register_driver);
 879
 880 int scsi_register_interface(struct class_interface *intf)
 881 {
 882         intf->class = &sdev_class;
 883
 884         return class_interface_register(intf);
 885 }
 886 EXPORT_SYMBOL(scsi_register_interface);
 887
 888
 889 static struct class_device_attribute *class_attr_overridden(
 890                 struct class_device_attribute **attrs,
 891                 struct class_device_attribute *attr)
 892 {
 893         int i;
 894
 895         if (!attrs)
 896                 return NULL;
 897         for (i = 0; attrs[i]; i++)
 898                 if (!strcmp(attrs[i]->attr.name, attr->attr.name))
 899                         return attrs[i];
 900         return NULL;
 901 }
 902
 903 static int class_attr_add(struct class_device *classdev,
 904                 struct class_device_attribute *attr)
 905 {
 906         struct class_device_attribute *base_attr;
 907
 908         /*
 909          * Spare the caller from having to copy things it's not interested in.
 910          */
 911         base_attr = class_attr_overridden(scsi_sysfs_shost_attrs, attr);
 912         if (base_attr) {
 913                 /* extend permissions */
 914                 attr->attr.mode |= base_attr->attr.mode;
 915
 916                 /* override null show/store with default */
 917                 if (!attr->show)
 918                         attr->show = base_attr->show;
 919                 if (!attr->store)
 920                         attr->store = base_attr->store;
 921         }
 922
 923         return class_device_create_file(classdev, attr);
 924 }
 925
 926 /**
 927  * scsi_sysfs_add_host - add scsi host to subsystem
 928  * @shost:     scsi host struct to add to subsystem
 929  * @dev:       parent struct device pointer
 930  **/
 931 int scsi_sysfs_add_host(struct Scsi_Host *shost)
 932 {
 933         int error, i;
 934
 935         if (shost->hostt->shost_attrs) {
 936                 for (i = 0; shost->hostt->shost_attrs[i]; i++) {
 937                         error = class_attr_add(&shost->shost_classdev,
 938                                         shost->hostt->shost_attrs[i]);
 939                         if (error)
 940                                 return error;
 941                 }
 942         }
 943
 944         for (i = 0; scsi_sysfs_shost_attrs[i]; i++) {
 945                 if (!class_attr_overridden(shost->hostt->shost_attrs,
 946                                         scsi_sysfs_shost_attrs[i])) {
 947                         error = class_device_create_file(&shost->shost_classdev,
 948                                         scsi_sysfs_shost_attrs[i]);
 949                         if (error)
 950                                 return error;
 951                 }
 952         }
 953
 954         transport_register_device(&shost->shost_gendev);
 955         return 0;
 956 }
 957
 958 static struct device_type scsi_dev_type = {
 959         .name =         "scsi_device",
 960         .release =      scsi_device_dev_release,
 961         .groups =       scsi_sdev_attr_groups,
 962 };
 963
 964 void scsi_sysfs_device_initialize(struct scsi_device *sdev)
 965 {
 966         unsigned long flags;
 967         struct Scsi_Host *shost = sdev->host;
 968         struct scsi_target  *starget = sdev->sdev_target;
 969
 970         device_initialize(&sdev->sdev_gendev);
 971         sdev->sdev_gendev.bus = &scsi_bus_type;
 972         sdev->sdev_gendev.type = &scsi_dev_type;
 973         sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
 974                 sdev->host->host_no, sdev->channel, sdev->id,
 975                 sdev->lun);
 976
 977         class_device_initialize(&sdev->sdev_classdev);
 978         sdev->sdev_classdev.dev = &sdev->sdev_gendev;
 979         sdev->sdev_classdev.class = &sdev_class;
 980         snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
 981                  "%d:%d:%d:%d", sdev->host->host_no,
 982                  sdev->channel, sdev->id, sdev->lun);
 983         sdev->scsi_level = starget->scsi_level;
 984         transport_setup_device(&sdev->sdev_gendev);
 985         spin_lock_irqsave(shost->host_lock, flags);
 986         list_add_tail(&sdev->same_target_siblings, &starget->devices);
 987         list_add_tail(&sdev->siblings, &shost->__devices);
 988         spin_unlock_irqrestore(shost->host_lock, flags);
 989 }
 990
 991 int scsi_is_sdev_device(const struct device *dev)
 992 {
 993         return dev->type == &scsi_dev_type;
 994 }
 995 EXPORT_SYMBOL(scsi_is_sdev_device);
 996
 997 /* A blank transport template that is used in drivers that don't
 998  * yet implement Transport Attributes */
 999 struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };