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