1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * scsi_scan.c 4 * 5 * Copyright (C) 2000 Eric Youngdale, 6 * Copyright (C) 2002 Patrick Mansfield 7 * 8 * The general scanning/probing algorithm is as follows, exceptions are 9 * made to it depending on device specific flags, compilation options, and 10 * global variable (boot or module load time) settings. 11 * 12 * A specific LUN is scanned via an INQUIRY command; if the LUN has a 13 * device attached, a scsi_device is allocated and setup for it. 14 * 15 * For every id of every channel on the given host: 16 * 17 * Scan LUN 0; if the target responds to LUN 0 (even if there is no 18 * device or storage attached to LUN 0): 19 * 20 * If LUN 0 has a device attached, allocate and setup a 21 * scsi_device for it. 22 * 23 * If target is SCSI-3 or up, issue a REPORT LUN, and scan 24 * all of the LUNs returned by the REPORT LUN; else, 25 * sequentially scan LUNs up until some maximum is reached, 26 * or a LUN is seen that cannot have a device attached to it. 27 */ 28 29 #include <linux/module.h> 30 #include <linux/moduleparam.h> 31 #include <linux/init.h> 32 #include <linux/blkdev.h> 33 #include <linux/delay.h> 34 #include <linux/kthread.h> 35 #include <linux/spinlock.h> 36 #include <linux/async.h> 37 #include <linux/slab.h> 38 #include <asm/unaligned.h> 39 40 #include <scsi/scsi.h> 41 #include <scsi/scsi_cmnd.h> 42 #include <scsi/scsi_device.h> 43 #include <scsi/scsi_driver.h> 44 #include <scsi/scsi_devinfo.h> 45 #include <scsi/scsi_host.h> 46 #include <scsi/scsi_transport.h> 47 #include <scsi/scsi_dh.h> 48 #include <scsi/scsi_eh.h> 49 50 #include "scsi_priv.h" 51 #include "scsi_logging.h" 52 53 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \ 54 " SCSI scanning, some SCSI devices might not be configured\n" 55 56 /* 57 * Default timeout 58 */ 59 #define SCSI_TIMEOUT (2*HZ) 60 #define SCSI_REPORT_LUNS_TIMEOUT (30*HZ) 61 62 /* 63 * Prefix values for the SCSI id's (stored in sysfs name field) 64 */ 65 #define SCSI_UID_SER_NUM 'S' 66 #define SCSI_UID_UNKNOWN 'Z' 67 68 /* 69 * Return values of some of the scanning functions. 70 * 71 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this 72 * includes allocation or general failures preventing IO from being sent. 73 * 74 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available 75 * on the given LUN. 76 * 77 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a 78 * given LUN. 79 */ 80 #define SCSI_SCAN_NO_RESPONSE 0 81 #define SCSI_SCAN_TARGET_PRESENT 1 82 #define SCSI_SCAN_LUN_PRESENT 2 83 84 static const char *scsi_null_device_strs = "nullnullnullnull"; 85 86 #define MAX_SCSI_LUNS 512 87 88 static u64 max_scsi_luns = MAX_SCSI_LUNS; 89 90 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR); 91 MODULE_PARM_DESC(max_luns, 92 "last scsi LUN (should be between 1 and 2^64-1)"); 93 94 #ifdef CONFIG_SCSI_SCAN_ASYNC 95 #define SCSI_SCAN_TYPE_DEFAULT "async" 96 #else 97 #define SCSI_SCAN_TYPE_DEFAULT "sync" 98 #endif 99 100 char scsi_scan_type[7] = SCSI_SCAN_TYPE_DEFAULT; 101 102 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), 103 S_IRUGO|S_IWUSR); 104 MODULE_PARM_DESC(scan, "sync, async, manual, or none. " 105 "Setting to 'manual' disables automatic scanning, but allows " 106 "for manual device scan via the 'scan' sysfs attribute."); 107 108 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18; 109 110 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); 111 MODULE_PARM_DESC(inq_timeout, 112 "Timeout (in seconds) waiting for devices to answer INQUIRY." 113 " Default is 20. Some devices may need more; most need less."); 114 115 /* This lock protects only this list */ 116 static DEFINE_SPINLOCK(async_scan_lock); 117 static LIST_HEAD(scanning_hosts); 118 119 struct async_scan_data { 120 struct list_head list; 121 struct Scsi_Host *shost; 122 struct completion prev_finished; 123 }; 124 125 /** 126 * scsi_complete_async_scans - Wait for asynchronous scans to complete 127 * 128 * When this function returns, any host which started scanning before 129 * this function was called will have finished its scan. Hosts which 130 * started scanning after this function was called may or may not have 131 * finished. 132 */ 133 int scsi_complete_async_scans(void) 134 { 135 struct async_scan_data *data; 136 137 do { 138 if (list_empty(&scanning_hosts)) 139 return 0; 140 /* If we can't get memory immediately, that's OK. Just 141 * sleep a little. Even if we never get memory, the async 142 * scans will finish eventually. 143 */ 144 data = kmalloc(sizeof(*data), GFP_KERNEL); 145 if (!data) 146 msleep(1); 147 } while (!data); 148 149 data->shost = NULL; 150 init_completion(&data->prev_finished); 151 152 spin_lock(&async_scan_lock); 153 /* Check that there's still somebody else on the list */ 154 if (list_empty(&scanning_hosts)) 155 goto done; 156 list_add_tail(&data->list, &scanning_hosts); 157 spin_unlock(&async_scan_lock); 158 159 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); 160 wait_for_completion(&data->prev_finished); 161 162 spin_lock(&async_scan_lock); 163 list_del(&data->list); 164 if (!list_empty(&scanning_hosts)) { 165 struct async_scan_data *next = list_entry(scanning_hosts.next, 166 struct async_scan_data, list); 167 complete(&next->prev_finished); 168 } 169 done: 170 spin_unlock(&async_scan_lock); 171 172 kfree(data); 173 return 0; 174 } 175 176 /** 177 * scsi_unlock_floptical - unlock device via a special MODE SENSE command 178 * @sdev: scsi device to send command to 179 * @result: area to store the result of the MODE SENSE 180 * 181 * Description: 182 * Send a vendor specific MODE SENSE (not a MODE SELECT) command. 183 * Called for BLIST_KEY devices. 184 **/ 185 static void scsi_unlock_floptical(struct scsi_device *sdev, 186 unsigned char *result) 187 { 188 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 189 190 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n"); 191 scsi_cmd[0] = MODE_SENSE; 192 scsi_cmd[1] = 0; 193 scsi_cmd[2] = 0x2e; 194 scsi_cmd[3] = 0; 195 scsi_cmd[4] = 0x2a; /* size */ 196 scsi_cmd[5] = 0; 197 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, 198 SCSI_TIMEOUT, 3, NULL); 199 } 200 201 /** 202 * scsi_alloc_sdev - allocate and setup a scsi_Device 203 * @starget: which target to allocate a &scsi_device for 204 * @lun: which lun 205 * @hostdata: usually NULL and set by ->slave_alloc instead 206 * 207 * Description: 208 * Allocate, initialize for io, and return a pointer to a scsi_Device. 209 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and 210 * adds scsi_Device to the appropriate list. 211 * 212 * Return value: 213 * scsi_Device pointer, or NULL on failure. 214 **/ 215 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, 216 u64 lun, void *hostdata) 217 { 218 unsigned int depth; 219 struct scsi_device *sdev; 220 struct request_queue *q; 221 int display_failure_msg = 1, ret; 222 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 223 224 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, 225 GFP_KERNEL); 226 if (!sdev) 227 goto out; 228 229 sdev->vendor = scsi_null_device_strs; 230 sdev->model = scsi_null_device_strs; 231 sdev->rev = scsi_null_device_strs; 232 sdev->host = shost; 233 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD; 234 sdev->id = starget->id; 235 sdev->lun = lun; 236 sdev->channel = starget->channel; 237 mutex_init(&sdev->state_mutex); 238 sdev->sdev_state = SDEV_CREATED; 239 INIT_LIST_HEAD(&sdev->siblings); 240 INIT_LIST_HEAD(&sdev->same_target_siblings); 241 INIT_LIST_HEAD(&sdev->starved_entry); 242 INIT_LIST_HEAD(&sdev->event_list); 243 spin_lock_init(&sdev->list_lock); 244 mutex_init(&sdev->inquiry_mutex); 245 INIT_WORK(&sdev->event_work, scsi_evt_thread); 246 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue); 247 248 sdev->sdev_gendev.parent = get_device(&starget->dev); 249 sdev->sdev_target = starget; 250 251 /* usually NULL and set by ->slave_alloc instead */ 252 sdev->hostdata = hostdata; 253 254 /* if the device needs this changing, it may do so in the 255 * slave_configure function */ 256 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; 257 258 /* 259 * Some low level driver could use device->type 260 */ 261 sdev->type = -1; 262 263 /* 264 * Assume that the device will have handshaking problems, 265 * and then fix this field later if it turns out it 266 * doesn't 267 */ 268 sdev->borken = 1; 269 270 sdev->sg_reserved_size = INT_MAX; 271 272 q = blk_mq_init_queue(&sdev->host->tag_set); 273 if (IS_ERR(q)) { 274 /* release fn is set up in scsi_sysfs_device_initialise, so 275 * have to free and put manually here */ 276 put_device(&starget->dev); 277 kfree(sdev); 278 goto out; 279 } 280 sdev->request_queue = q; 281 q->queuedata = sdev; 282 __scsi_init_queue(sdev->host, q); 283 blk_queue_flag_set(QUEUE_FLAG_SCSI_PASSTHROUGH, q); 284 WARN_ON_ONCE(!blk_get_queue(q)); 285 286 depth = sdev->host->cmd_per_lun ?: 1; 287 288 /* 289 * Use .can_queue as budget map's depth because we have to 290 * support adjusting queue depth from sysfs. Meantime use 291 * default device queue depth to figure out sbitmap shift 292 * since we use this queue depth most of times. 293 */ 294 if (sbitmap_init_node(&sdev->budget_map, 295 scsi_device_max_queue_depth(sdev), 296 sbitmap_calculate_shift(depth), 297 GFP_KERNEL, sdev->request_queue->node, 298 false, true)) { 299 put_device(&starget->dev); 300 kfree(sdev); 301 goto out; 302 } 303 304 scsi_change_queue_depth(sdev, depth); 305 306 scsi_sysfs_device_initialize(sdev); 307 308 if (shost->hostt->slave_alloc) { 309 ret = shost->hostt->slave_alloc(sdev); 310 if (ret) { 311 /* 312 * if LLDD reports slave not present, don't clutter 313 * console with alloc failure messages 314 */ 315 if (ret == -ENXIO) 316 display_failure_msg = 0; 317 goto out_device_destroy; 318 } 319 } 320 321 return sdev; 322 323 out_device_destroy: 324 __scsi_remove_device(sdev); 325 out: 326 if (display_failure_msg) 327 printk(ALLOC_FAILURE_MSG, __func__); 328 return NULL; 329 } 330 331 static void scsi_target_destroy(struct scsi_target *starget) 332 { 333 struct device *dev = &starget->dev; 334 struct Scsi_Host *shost = dev_to_shost(dev->parent); 335 unsigned long flags; 336 337 BUG_ON(starget->state == STARGET_DEL); 338 starget->state = STARGET_DEL; 339 transport_destroy_device(dev); 340 spin_lock_irqsave(shost->host_lock, flags); 341 if (shost->hostt->target_destroy) 342 shost->hostt->target_destroy(starget); 343 list_del_init(&starget->siblings); 344 spin_unlock_irqrestore(shost->host_lock, flags); 345 put_device(dev); 346 } 347 348 static void scsi_target_dev_release(struct device *dev) 349 { 350 struct device *parent = dev->parent; 351 struct scsi_target *starget = to_scsi_target(dev); 352 353 kfree(starget); 354 put_device(parent); 355 } 356 357 static struct device_type scsi_target_type = { 358 .name = "scsi_target", 359 .release = scsi_target_dev_release, 360 }; 361 362 int scsi_is_target_device(const struct device *dev) 363 { 364 return dev->type == &scsi_target_type; 365 } 366 EXPORT_SYMBOL(scsi_is_target_device); 367 368 static struct scsi_target *__scsi_find_target(struct device *parent, 369 int channel, uint id) 370 { 371 struct scsi_target *starget, *found_starget = NULL; 372 struct Scsi_Host *shost = dev_to_shost(parent); 373 /* 374 * Search for an existing target for this sdev. 375 */ 376 list_for_each_entry(starget, &shost->__targets, siblings) { 377 if (starget->id == id && 378 starget->channel == channel) { 379 found_starget = starget; 380 break; 381 } 382 } 383 if (found_starget) 384 get_device(&found_starget->dev); 385 386 return found_starget; 387 } 388 389 /** 390 * scsi_target_reap_ref_release - remove target from visibility 391 * @kref: the reap_ref in the target being released 392 * 393 * Called on last put of reap_ref, which is the indication that no device 394 * under this target is visible anymore, so render the target invisible in 395 * sysfs. Note: we have to be in user context here because the target reaps 396 * should be done in places where the scsi device visibility is being removed. 397 */ 398 static void scsi_target_reap_ref_release(struct kref *kref) 399 { 400 struct scsi_target *starget 401 = container_of(kref, struct scsi_target, reap_ref); 402 403 /* 404 * if we get here and the target is still in a CREATED state that 405 * means it was allocated but never made visible (because a scan 406 * turned up no LUNs), so don't call device_del() on it. 407 */ 408 if ((starget->state != STARGET_CREATED) && 409 (starget->state != STARGET_CREATED_REMOVE)) { 410 transport_remove_device(&starget->dev); 411 device_del(&starget->dev); 412 } 413 scsi_target_destroy(starget); 414 } 415 416 static void scsi_target_reap_ref_put(struct scsi_target *starget) 417 { 418 kref_put(&starget->reap_ref, scsi_target_reap_ref_release); 419 } 420 421 /** 422 * scsi_alloc_target - allocate a new or find an existing target 423 * @parent: parent of the target (need not be a scsi host) 424 * @channel: target channel number (zero if no channels) 425 * @id: target id number 426 * 427 * Return an existing target if one exists, provided it hasn't already 428 * gone into STARGET_DEL state, otherwise allocate a new target. 429 * 430 * The target is returned with an incremented reference, so the caller 431 * is responsible for both reaping and doing a last put 432 */ 433 static struct scsi_target *scsi_alloc_target(struct device *parent, 434 int channel, uint id) 435 { 436 struct Scsi_Host *shost = dev_to_shost(parent); 437 struct device *dev = NULL; 438 unsigned long flags; 439 const int size = sizeof(struct scsi_target) 440 + shost->transportt->target_size; 441 struct scsi_target *starget; 442 struct scsi_target *found_target; 443 int error, ref_got; 444 445 starget = kzalloc(size, GFP_KERNEL); 446 if (!starget) { 447 printk(KERN_ERR "%s: allocation failure\n", __func__); 448 return NULL; 449 } 450 dev = &starget->dev; 451 device_initialize(dev); 452 kref_init(&starget->reap_ref); 453 dev->parent = get_device(parent); 454 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); 455 dev->bus = &scsi_bus_type; 456 dev->type = &scsi_target_type; 457 starget->id = id; 458 starget->channel = channel; 459 starget->can_queue = 0; 460 INIT_LIST_HEAD(&starget->siblings); 461 INIT_LIST_HEAD(&starget->devices); 462 starget->state = STARGET_CREATED; 463 starget->scsi_level = SCSI_2; 464 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; 465 retry: 466 spin_lock_irqsave(shost->host_lock, flags); 467 468 found_target = __scsi_find_target(parent, channel, id); 469 if (found_target) 470 goto found; 471 472 list_add_tail(&starget->siblings, &shost->__targets); 473 spin_unlock_irqrestore(shost->host_lock, flags); 474 /* allocate and add */ 475 transport_setup_device(dev); 476 if (shost->hostt->target_alloc) { 477 error = shost->hostt->target_alloc(starget); 478 479 if(error) { 480 if (error != -ENXIO) 481 dev_err(dev, "target allocation failed, error %d\n", error); 482 /* don't want scsi_target_reap to do the final 483 * put because it will be under the host lock */ 484 scsi_target_destroy(starget); 485 return NULL; 486 } 487 } 488 get_device(dev); 489 490 return starget; 491 492 found: 493 /* 494 * release routine already fired if kref is zero, so if we can still 495 * take the reference, the target must be alive. If we can't, it must 496 * be dying and we need to wait for a new target 497 */ 498 ref_got = kref_get_unless_zero(&found_target->reap_ref); 499 500 spin_unlock_irqrestore(shost->host_lock, flags); 501 if (ref_got) { 502 put_device(dev); 503 return found_target; 504 } 505 /* 506 * Unfortunately, we found a dying target; need to wait until it's 507 * dead before we can get a new one. There is an anomaly here. We 508 * *should* call scsi_target_reap() to balance the kref_get() of the 509 * reap_ref above. However, since the target being released, it's 510 * already invisible and the reap_ref is irrelevant. If we call 511 * scsi_target_reap() we might spuriously do another device_del() on 512 * an already invisible target. 513 */ 514 put_device(&found_target->dev); 515 /* 516 * length of time is irrelevant here, we just want to yield the CPU 517 * for a tick to avoid busy waiting for the target to die. 518 */ 519 msleep(1); 520 goto retry; 521 } 522 523 /** 524 * scsi_target_reap - check to see if target is in use and destroy if not 525 * @starget: target to be checked 526 * 527 * This is used after removing a LUN or doing a last put of the target 528 * it checks atomically that nothing is using the target and removes 529 * it if so. 530 */ 531 void scsi_target_reap(struct scsi_target *starget) 532 { 533 /* 534 * serious problem if this triggers: STARGET_DEL is only set in the if 535 * the reap_ref drops to zero, so we're trying to do another final put 536 * on an already released kref 537 */ 538 BUG_ON(starget->state == STARGET_DEL); 539 scsi_target_reap_ref_put(starget); 540 } 541 542 /** 543 * scsi_sanitize_inquiry_string - remove non-graphical chars from an 544 * INQUIRY result string 545 * @s: INQUIRY result string to sanitize 546 * @len: length of the string 547 * 548 * Description: 549 * The SCSI spec says that INQUIRY vendor, product, and revision 550 * strings must consist entirely of graphic ASCII characters, 551 * padded on the right with spaces. Since not all devices obey 552 * this rule, we will replace non-graphic or non-ASCII characters 553 * with spaces. Exception: a NUL character is interpreted as a 554 * string terminator, so all the following characters are set to 555 * spaces. 556 **/ 557 void scsi_sanitize_inquiry_string(unsigned char *s, int len) 558 { 559 int terminated = 0; 560 561 for (; len > 0; (--len, ++s)) { 562 if (*s == 0) 563 terminated = 1; 564 if (terminated || *s < 0x20 || *s > 0x7e) 565 *s = ' '; 566 } 567 } 568 EXPORT_SYMBOL(scsi_sanitize_inquiry_string); 569 570 /** 571 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY 572 * @sdev: scsi_device to probe 573 * @inq_result: area to store the INQUIRY result 574 * @result_len: len of inq_result 575 * @bflags: store any bflags found here 576 * 577 * Description: 578 * Probe the lun associated with @req using a standard SCSI INQUIRY; 579 * 580 * If the INQUIRY is successful, zero is returned and the 581 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length 582 * are copied to the scsi_device any flags value is stored in *@bflags. 583 **/ 584 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, 585 int result_len, blist_flags_t *bflags) 586 { 587 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 588 int first_inquiry_len, try_inquiry_len, next_inquiry_len; 589 int response_len = 0; 590 int pass, count, result; 591 struct scsi_sense_hdr sshdr; 592 593 *bflags = 0; 594 595 /* Perform up to 3 passes. The first pass uses a conservative 596 * transfer length of 36 unless sdev->inquiry_len specifies a 597 * different value. */ 598 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; 599 try_inquiry_len = first_inquiry_len; 600 pass = 1; 601 602 next_pass: 603 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 604 "scsi scan: INQUIRY pass %d length %d\n", 605 pass, try_inquiry_len)); 606 607 /* Each pass gets up to three chances to ignore Unit Attention */ 608 for (count = 0; count < 3; ++count) { 609 int resid; 610 611 memset(scsi_cmd, 0, 6); 612 scsi_cmd[0] = INQUIRY; 613 scsi_cmd[4] = (unsigned char) try_inquiry_len; 614 615 memset(inq_result, 0, try_inquiry_len); 616 617 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 618 inq_result, try_inquiry_len, &sshdr, 619 HZ / 2 + HZ * scsi_inq_timeout, 3, 620 &resid); 621 622 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 623 "scsi scan: INQUIRY %s with code 0x%x\n", 624 result ? "failed" : "successful", result)); 625 626 if (result > 0) { 627 /* 628 * not-ready to ready transition [asc/ascq=0x28/0x0] 629 * or power-on, reset [asc/ascq=0x29/0x0], continue. 630 * INQUIRY should not yield UNIT_ATTENTION 631 * but many buggy devices do so anyway. 632 */ 633 if (scsi_status_is_check_condition(result) && 634 scsi_sense_valid(&sshdr)) { 635 if ((sshdr.sense_key == UNIT_ATTENTION) && 636 ((sshdr.asc == 0x28) || 637 (sshdr.asc == 0x29)) && 638 (sshdr.ascq == 0)) 639 continue; 640 } 641 } else if (result == 0) { 642 /* 643 * if nothing was transferred, we try 644 * again. It's a workaround for some USB 645 * devices. 646 */ 647 if (resid == try_inquiry_len) 648 continue; 649 } 650 break; 651 } 652 653 if (result == 0) { 654 scsi_sanitize_inquiry_string(&inq_result[8], 8); 655 scsi_sanitize_inquiry_string(&inq_result[16], 16); 656 scsi_sanitize_inquiry_string(&inq_result[32], 4); 657 658 response_len = inq_result[4] + 5; 659 if (response_len > 255) 660 response_len = first_inquiry_len; /* sanity */ 661 662 /* 663 * Get any flags for this device. 664 * 665 * XXX add a bflags to scsi_device, and replace the 666 * corresponding bit fields in scsi_device, so bflags 667 * need not be passed as an argument. 668 */ 669 *bflags = scsi_get_device_flags(sdev, &inq_result[8], 670 &inq_result[16]); 671 672 /* When the first pass succeeds we gain information about 673 * what larger transfer lengths might work. */ 674 if (pass == 1) { 675 if (BLIST_INQUIRY_36 & *bflags) 676 next_inquiry_len = 36; 677 else if (sdev->inquiry_len) 678 next_inquiry_len = sdev->inquiry_len; 679 else 680 next_inquiry_len = response_len; 681 682 /* If more data is available perform the second pass */ 683 if (next_inquiry_len > try_inquiry_len) { 684 try_inquiry_len = next_inquiry_len; 685 pass = 2; 686 goto next_pass; 687 } 688 } 689 690 } else if (pass == 2) { 691 sdev_printk(KERN_INFO, sdev, 692 "scsi scan: %d byte inquiry failed. " 693 "Consider BLIST_INQUIRY_36 for this device\n", 694 try_inquiry_len); 695 696 /* If this pass failed, the third pass goes back and transfers 697 * the same amount as we successfully got in the first pass. */ 698 try_inquiry_len = first_inquiry_len; 699 pass = 3; 700 goto next_pass; 701 } 702 703 /* If the last transfer attempt got an error, assume the 704 * peripheral doesn't exist or is dead. */ 705 if (result) 706 return -EIO; 707 708 /* Don't report any more data than the device says is valid */ 709 sdev->inquiry_len = min(try_inquiry_len, response_len); 710 711 /* 712 * XXX Abort if the response length is less than 36? If less than 713 * 32, the lookup of the device flags (above) could be invalid, 714 * and it would be possible to take an incorrect action - we do 715 * not want to hang because of a short INQUIRY. On the flip side, 716 * if the device is spun down or becoming ready (and so it gives a 717 * short INQUIRY), an abort here prevents any further use of the 718 * device, including spin up. 719 * 720 * On the whole, the best approach seems to be to assume the first 721 * 36 bytes are valid no matter what the device says. That's 722 * better than copying < 36 bytes to the inquiry-result buffer 723 * and displaying garbage for the Vendor, Product, or Revision 724 * strings. 725 */ 726 if (sdev->inquiry_len < 36) { 727 if (!sdev->host->short_inquiry) { 728 shost_printk(KERN_INFO, sdev->host, 729 "scsi scan: INQUIRY result too short (%d)," 730 " using 36\n", sdev->inquiry_len); 731 sdev->host->short_inquiry = 1; 732 } 733 sdev->inquiry_len = 36; 734 } 735 736 /* 737 * Related to the above issue: 738 * 739 * XXX Devices (disk or all?) should be sent a TEST UNIT READY, 740 * and if not ready, sent a START_STOP to start (maybe spin up) and 741 * then send the INQUIRY again, since the INQUIRY can change after 742 * a device is initialized. 743 * 744 * Ideally, start a device if explicitly asked to do so. This 745 * assumes that a device is spun up on power on, spun down on 746 * request, and then spun up on request. 747 */ 748 749 /* 750 * The scanning code needs to know the scsi_level, even if no 751 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so 752 * non-zero LUNs can be scanned. 753 */ 754 sdev->scsi_level = inq_result[2] & 0x07; 755 if (sdev->scsi_level >= 2 || 756 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) 757 sdev->scsi_level++; 758 sdev->sdev_target->scsi_level = sdev->scsi_level; 759 760 /* 761 * If SCSI-2 or lower, and if the transport requires it, 762 * store the LUN value in CDB[1]. 763 */ 764 sdev->lun_in_cdb = 0; 765 if (sdev->scsi_level <= SCSI_2 && 766 sdev->scsi_level != SCSI_UNKNOWN && 767 !sdev->host->no_scsi2_lun_in_cdb) 768 sdev->lun_in_cdb = 1; 769 770 return 0; 771 } 772 773 /** 774 * scsi_add_lun - allocate and fully initialze a scsi_device 775 * @sdev: holds information to be stored in the new scsi_device 776 * @inq_result: holds the result of a previous INQUIRY to the LUN 777 * @bflags: black/white list flag 778 * @async: 1 if this device is being scanned asynchronously 779 * 780 * Description: 781 * Initialize the scsi_device @sdev. Optionally set fields based 782 * on values in *@bflags. 783 * 784 * Return: 785 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 786 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 787 **/ 788 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, 789 blist_flags_t *bflags, int async) 790 { 791 int ret; 792 793 /* 794 * XXX do not save the inquiry, since it can change underneath us, 795 * save just vendor/model/rev. 796 * 797 * Rather than save it and have an ioctl that retrieves the saved 798 * value, have an ioctl that executes the same INQUIRY code used 799 * in scsi_probe_lun, let user level programs doing INQUIRY 800 * scanning run at their own risk, or supply a user level program 801 * that can correctly scan. 802 */ 803 804 /* 805 * Copy at least 36 bytes of INQUIRY data, so that we don't 806 * dereference unallocated memory when accessing the Vendor, 807 * Product, and Revision strings. Badly behaved devices may set 808 * the INQUIRY Additional Length byte to a small value, indicating 809 * these strings are invalid, but often they contain plausible data 810 * nonetheless. It doesn't matter if the device sent < 36 bytes 811 * total, since scsi_probe_lun() initializes inq_result with 0s. 812 */ 813 sdev->inquiry = kmemdup(inq_result, 814 max_t(size_t, sdev->inquiry_len, 36), 815 GFP_KERNEL); 816 if (sdev->inquiry == NULL) 817 return SCSI_SCAN_NO_RESPONSE; 818 819 sdev->vendor = (char *) (sdev->inquiry + 8); 820 sdev->model = (char *) (sdev->inquiry + 16); 821 sdev->rev = (char *) (sdev->inquiry + 32); 822 823 if (strncmp(sdev->vendor, "ATA ", 8) == 0) { 824 /* 825 * sata emulation layer device. This is a hack to work around 826 * the SATL power management specifications which state that 827 * when the SATL detects the device has gone into standby 828 * mode, it shall respond with NOT READY. 829 */ 830 sdev->allow_restart = 1; 831 } 832 833 if (*bflags & BLIST_ISROM) { 834 sdev->type = TYPE_ROM; 835 sdev->removable = 1; 836 } else { 837 sdev->type = (inq_result[0] & 0x1f); 838 sdev->removable = (inq_result[1] & 0x80) >> 7; 839 840 /* 841 * some devices may respond with wrong type for 842 * well-known logical units. Force well-known type 843 * to enumerate them correctly. 844 */ 845 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) { 846 sdev_printk(KERN_WARNING, sdev, 847 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n", 848 __func__, sdev->type, (unsigned int)sdev->lun); 849 sdev->type = TYPE_WLUN; 850 } 851 852 } 853 854 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { 855 /* RBC and MMC devices can return SCSI-3 compliance and yet 856 * still not support REPORT LUNS, so make them act as 857 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is 858 * specifically set */ 859 if ((*bflags & BLIST_REPORTLUN2) == 0) 860 *bflags |= BLIST_NOREPORTLUN; 861 } 862 863 /* 864 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI 865 * spec says: The device server is capable of supporting the 866 * specified peripheral device type on this logical unit. However, 867 * the physical device is not currently connected to this logical 868 * unit. 869 * 870 * The above is vague, as it implies that we could treat 001 and 871 * 011 the same. Stay compatible with previous code, and create a 872 * scsi_device for a PQ of 1 873 * 874 * Don't set the device offline here; rather let the upper 875 * level drivers eval the PQ to decide whether they should 876 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. 877 */ 878 879 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; 880 sdev->lockable = sdev->removable; 881 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); 882 883 if (sdev->scsi_level >= SCSI_3 || 884 (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) 885 sdev->ppr = 1; 886 if (inq_result[7] & 0x60) 887 sdev->wdtr = 1; 888 if (inq_result[7] & 0x10) 889 sdev->sdtr = 1; 890 891 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " 892 "ANSI: %d%s\n", scsi_device_type(sdev->type), 893 sdev->vendor, sdev->model, sdev->rev, 894 sdev->inq_periph_qual, inq_result[2] & 0x07, 895 (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); 896 897 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && 898 !(*bflags & BLIST_NOTQ)) { 899 sdev->tagged_supported = 1; 900 sdev->simple_tags = 1; 901 } 902 903 /* 904 * Some devices (Texel CD ROM drives) have handshaking problems 905 * when used with the Seagate controllers. borken is initialized 906 * to 1, and then set it to 0 here. 907 */ 908 if ((*bflags & BLIST_BORKEN) == 0) 909 sdev->borken = 0; 910 911 if (*bflags & BLIST_NO_ULD_ATTACH) 912 sdev->no_uld_attach = 1; 913 914 /* 915 * Apparently some really broken devices (contrary to the SCSI 916 * standards) need to be selected without asserting ATN 917 */ 918 if (*bflags & BLIST_SELECT_NO_ATN) 919 sdev->select_no_atn = 1; 920 921 /* 922 * Maximum 512 sector transfer length 923 * broken RA4x00 Compaq Disk Array 924 */ 925 if (*bflags & BLIST_MAX_512) 926 blk_queue_max_hw_sectors(sdev->request_queue, 512); 927 /* 928 * Max 1024 sector transfer length for targets that report incorrect 929 * max/optimal lengths and relied on the old block layer safe default 930 */ 931 else if (*bflags & BLIST_MAX_1024) 932 blk_queue_max_hw_sectors(sdev->request_queue, 1024); 933 934 /* 935 * Some devices may not want to have a start command automatically 936 * issued when a device is added. 937 */ 938 if (*bflags & BLIST_NOSTARTONADD) 939 sdev->no_start_on_add = 1; 940 941 if (*bflags & BLIST_SINGLELUN) 942 scsi_target(sdev)->single_lun = 1; 943 944 sdev->use_10_for_rw = 1; 945 946 /* some devices don't like REPORT SUPPORTED OPERATION CODES 947 * and will simply timeout causing sd_mod init to take a very 948 * very long time */ 949 if (*bflags & BLIST_NO_RSOC) 950 sdev->no_report_opcodes = 1; 951 952 /* set the device running here so that slave configure 953 * may do I/O */ 954 mutex_lock(&sdev->state_mutex); 955 ret = scsi_device_set_state(sdev, SDEV_RUNNING); 956 if (ret) 957 ret = scsi_device_set_state(sdev, SDEV_BLOCK); 958 mutex_unlock(&sdev->state_mutex); 959 960 if (ret) { 961 sdev_printk(KERN_ERR, sdev, 962 "in wrong state %s to complete scan\n", 963 scsi_device_state_name(sdev->sdev_state)); 964 return SCSI_SCAN_NO_RESPONSE; 965 } 966 967 if (*bflags & BLIST_NOT_LOCKABLE) 968 sdev->lockable = 0; 969 970 if (*bflags & BLIST_RETRY_HWERROR) 971 sdev->retry_hwerror = 1; 972 973 if (*bflags & BLIST_NO_DIF) 974 sdev->no_dif = 1; 975 976 if (*bflags & BLIST_UNMAP_LIMIT_WS) 977 sdev->unmap_limit_for_ws = 1; 978 979 if (*bflags & BLIST_IGN_MEDIA_CHANGE) 980 sdev->ignore_media_change = 1; 981 982 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; 983 984 if (*bflags & BLIST_TRY_VPD_PAGES) 985 sdev->try_vpd_pages = 1; 986 else if (*bflags & BLIST_SKIP_VPD_PAGES) 987 sdev->skip_vpd_pages = 1; 988 989 transport_configure_device(&sdev->sdev_gendev); 990 991 if (sdev->host->hostt->slave_configure) { 992 ret = sdev->host->hostt->slave_configure(sdev); 993 if (ret) { 994 /* 995 * if LLDD reports slave not present, don't clutter 996 * console with alloc failure messages 997 */ 998 if (ret != -ENXIO) { 999 sdev_printk(KERN_ERR, sdev, 1000 "failed to configure device\n"); 1001 } 1002 return SCSI_SCAN_NO_RESPONSE; 1003 } 1004 } 1005 1006 if (sdev->scsi_level >= SCSI_3) 1007 scsi_attach_vpd(sdev); 1008 1009 sdev->max_queue_depth = sdev->queue_depth; 1010 WARN_ON_ONCE(sdev->max_queue_depth > sdev->budget_map.depth); 1011 sdev->sdev_bflags = *bflags; 1012 1013 /* 1014 * Ok, the device is now all set up, we can 1015 * register it and tell the rest of the kernel 1016 * about it. 1017 */ 1018 if (!async && scsi_sysfs_add_sdev(sdev) != 0) 1019 return SCSI_SCAN_NO_RESPONSE; 1020 1021 return SCSI_SCAN_LUN_PRESENT; 1022 } 1023 1024 #ifdef CONFIG_SCSI_LOGGING 1025 /** 1026 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace 1027 * @buf: Output buffer with at least end-first+1 bytes of space 1028 * @inq: Inquiry buffer (input) 1029 * @first: Offset of string into inq 1030 * @end: Index after last character in inq 1031 */ 1032 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, 1033 unsigned first, unsigned end) 1034 { 1035 unsigned term = 0, idx; 1036 1037 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { 1038 if (inq[idx+first] > ' ') { 1039 buf[idx] = inq[idx+first]; 1040 term = idx+1; 1041 } else { 1042 buf[idx] = ' '; 1043 } 1044 } 1045 buf[term] = 0; 1046 return buf; 1047 } 1048 #endif 1049 1050 /** 1051 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it 1052 * @starget: pointer to target device structure 1053 * @lun: LUN of target device 1054 * @bflagsp: store bflags here if not NULL 1055 * @sdevp: probe the LUN corresponding to this scsi_device 1056 * @rescan: if not equal to SCSI_SCAN_INITIAL skip some code only 1057 * needed on first scan 1058 * @hostdata: passed to scsi_alloc_sdev() 1059 * 1060 * Description: 1061 * Call scsi_probe_lun, if a LUN with an attached device is found, 1062 * allocate and set it up by calling scsi_add_lun. 1063 * 1064 * Return: 1065 * 1066 * - SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 1067 * - SCSI_SCAN_TARGET_PRESENT: target responded, but no device is 1068 * attached at the LUN 1069 * - SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 1070 **/ 1071 static int scsi_probe_and_add_lun(struct scsi_target *starget, 1072 u64 lun, blist_flags_t *bflagsp, 1073 struct scsi_device **sdevp, 1074 enum scsi_scan_mode rescan, 1075 void *hostdata) 1076 { 1077 struct scsi_device *sdev; 1078 unsigned char *result; 1079 blist_flags_t bflags; 1080 int res = SCSI_SCAN_NO_RESPONSE, result_len = 256; 1081 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1082 1083 /* 1084 * The rescan flag is used as an optimization, the first scan of a 1085 * host adapter calls into here with rescan == 0. 1086 */ 1087 sdev = scsi_device_lookup_by_target(starget, lun); 1088 if (sdev) { 1089 if (rescan != SCSI_SCAN_INITIAL || !scsi_device_created(sdev)) { 1090 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1091 "scsi scan: device exists on %s\n", 1092 dev_name(&sdev->sdev_gendev))); 1093 if (sdevp) 1094 *sdevp = sdev; 1095 else 1096 scsi_device_put(sdev); 1097 1098 if (bflagsp) 1099 *bflagsp = scsi_get_device_flags(sdev, 1100 sdev->vendor, 1101 sdev->model); 1102 return SCSI_SCAN_LUN_PRESENT; 1103 } 1104 scsi_device_put(sdev); 1105 } else 1106 sdev = scsi_alloc_sdev(starget, lun, hostdata); 1107 if (!sdev) 1108 goto out; 1109 1110 result = kmalloc(result_len, GFP_KERNEL); 1111 if (!result) 1112 goto out_free_sdev; 1113 1114 if (scsi_probe_lun(sdev, result, result_len, &bflags)) 1115 goto out_free_result; 1116 1117 if (bflagsp) 1118 *bflagsp = bflags; 1119 /* 1120 * result contains valid SCSI INQUIRY data. 1121 */ 1122 if ((result[0] >> 5) == 3) { 1123 /* 1124 * For a Peripheral qualifier 3 (011b), the SCSI 1125 * spec says: The device server is not capable of 1126 * supporting a physical device on this logical 1127 * unit. 1128 * 1129 * For disks, this implies that there is no 1130 * logical disk configured at sdev->lun, but there 1131 * is a target id responding. 1132 */ 1133 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" 1134 " peripheral qualifier of 3, device not" 1135 " added\n")) 1136 if (lun == 0) { 1137 SCSI_LOG_SCAN_BUS(1, { 1138 unsigned char vend[9]; 1139 unsigned char mod[17]; 1140 1141 sdev_printk(KERN_INFO, sdev, 1142 "scsi scan: consider passing scsi_mod." 1143 "dev_flags=%s:%s:0x240 or 0x1000240\n", 1144 scsi_inq_str(vend, result, 8, 16), 1145 scsi_inq_str(mod, result, 16, 32)); 1146 }); 1147 1148 } 1149 1150 res = SCSI_SCAN_TARGET_PRESENT; 1151 goto out_free_result; 1152 } 1153 1154 /* 1155 * Some targets may set slight variations of PQ and PDT to signal 1156 * that no LUN is present, so don't add sdev in these cases. 1157 * Two specific examples are: 1158 * 1) NetApp targets: return PQ=1, PDT=0x1f 1159 * 2) IBM/2145 targets: return PQ=1, PDT=0 1160 * 3) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" 1161 * in the UFI 1.0 spec (we cannot rely on reserved bits). 1162 * 1163 * References: 1164 * 1) SCSI SPC-3, pp. 145-146 1165 * PQ=1: "A peripheral device having the specified peripheral 1166 * device type is not connected to this logical unit. However, the 1167 * device server is capable of supporting the specified peripheral 1168 * device type on this logical unit." 1169 * PDT=0x1f: "Unknown or no device type" 1170 * 2) USB UFI 1.0, p. 20 1171 * PDT=00h Direct-access device (floppy) 1172 * PDT=1Fh none (no FDD connected to the requested logical unit) 1173 */ 1174 if (((result[0] >> 5) == 1 || 1175 (starget->pdt_1f_for_no_lun && (result[0] & 0x1f) == 0x1f)) && 1176 !scsi_is_wlun(lun)) { 1177 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1178 "scsi scan: peripheral device type" 1179 " of 31, no device added\n")); 1180 res = SCSI_SCAN_TARGET_PRESENT; 1181 goto out_free_result; 1182 } 1183 1184 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); 1185 if (res == SCSI_SCAN_LUN_PRESENT) { 1186 if (bflags & BLIST_KEY) { 1187 sdev->lockable = 0; 1188 scsi_unlock_floptical(sdev, result); 1189 } 1190 } 1191 1192 out_free_result: 1193 kfree(result); 1194 out_free_sdev: 1195 if (res == SCSI_SCAN_LUN_PRESENT) { 1196 if (sdevp) { 1197 if (scsi_device_get(sdev) == 0) { 1198 *sdevp = sdev; 1199 } else { 1200 __scsi_remove_device(sdev); 1201 res = SCSI_SCAN_NO_RESPONSE; 1202 } 1203 } 1204 } else 1205 __scsi_remove_device(sdev); 1206 out: 1207 return res; 1208 } 1209 1210 /** 1211 * scsi_sequential_lun_scan - sequentially scan a SCSI target 1212 * @starget: pointer to target structure to scan 1213 * @bflags: black/white list flag for LUN 0 1214 * @scsi_level: Which version of the standard does this device adhere to 1215 * @rescan: passed to scsi_probe_add_lun() 1216 * 1217 * Description: 1218 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been 1219 * scanned) to some maximum lun until a LUN is found with no device 1220 * attached. Use the bflags to figure out any oddities. 1221 * 1222 * Modifies sdevscan->lun. 1223 **/ 1224 static void scsi_sequential_lun_scan(struct scsi_target *starget, 1225 blist_flags_t bflags, int scsi_level, 1226 enum scsi_scan_mode rescan) 1227 { 1228 uint max_dev_lun; 1229 u64 sparse_lun, lun; 1230 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1231 1232 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget, 1233 "scsi scan: Sequential scan\n")); 1234 1235 max_dev_lun = min(max_scsi_luns, shost->max_lun); 1236 /* 1237 * If this device is known to support sparse multiple units, 1238 * override the other settings, and scan all of them. Normally, 1239 * SCSI-3 devices should be scanned via the REPORT LUNS. 1240 */ 1241 if (bflags & BLIST_SPARSELUN) { 1242 max_dev_lun = shost->max_lun; 1243 sparse_lun = 1; 1244 } else 1245 sparse_lun = 0; 1246 1247 /* 1248 * If less than SCSI_1_CCS, and no special lun scanning, stop 1249 * scanning; this matches 2.4 behaviour, but could just be a bug 1250 * (to continue scanning a SCSI_1_CCS device). 1251 * 1252 * This test is broken. We might not have any device on lun0 for 1253 * a sparselun device, and if that's the case then how would we 1254 * know the real scsi_level, eh? It might make sense to just not 1255 * scan any SCSI_1 device for non-0 luns, but that check would best 1256 * go into scsi_alloc_sdev() and just have it return null when asked 1257 * to alloc an sdev for lun > 0 on an already found SCSI_1 device. 1258 * 1259 if ((sdevscan->scsi_level < SCSI_1_CCS) && 1260 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) 1261 == 0)) 1262 return; 1263 */ 1264 /* 1265 * If this device is known to support multiple units, override 1266 * the other settings, and scan all of them. 1267 */ 1268 if (bflags & BLIST_FORCELUN) 1269 max_dev_lun = shost->max_lun; 1270 /* 1271 * REGAL CDC-4X: avoid hang after LUN 4 1272 */ 1273 if (bflags & BLIST_MAX5LUN) 1274 max_dev_lun = min(5U, max_dev_lun); 1275 /* 1276 * Do not scan SCSI-2 or lower device past LUN 7, unless 1277 * BLIST_LARGELUN. 1278 */ 1279 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) 1280 max_dev_lun = min(8U, max_dev_lun); 1281 else 1282 max_dev_lun = min(256U, max_dev_lun); 1283 1284 /* 1285 * We have already scanned LUN 0, so start at LUN 1. Keep scanning 1286 * until we reach the max, or no LUN is found and we are not 1287 * sparse_lun. 1288 */ 1289 for (lun = 1; lun < max_dev_lun; ++lun) 1290 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, 1291 NULL) != SCSI_SCAN_LUN_PRESENT) && 1292 !sparse_lun) 1293 return; 1294 } 1295 1296 /** 1297 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results 1298 * @starget: which target 1299 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN 1300 * @rescan: nonzero if we can skip code only needed on first scan 1301 * 1302 * Description: 1303 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. 1304 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. 1305 * 1306 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 1307 * LUNs even if it's older than SCSI-3. 1308 * If BLIST_NOREPORTLUN is set, return 1 always. 1309 * If BLIST_NOLUN is set, return 0 always. 1310 * If starget->no_report_luns is set, return 1 always. 1311 * 1312 * Return: 1313 * 0: scan completed (or no memory, so further scanning is futile) 1314 * 1: could not scan with REPORT LUN 1315 **/ 1316 static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflags, 1317 enum scsi_scan_mode rescan) 1318 { 1319 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 1320 unsigned int length; 1321 u64 lun; 1322 unsigned int num_luns; 1323 unsigned int retries; 1324 int result; 1325 struct scsi_lun *lunp, *lun_data; 1326 struct scsi_sense_hdr sshdr; 1327 struct scsi_device *sdev; 1328 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 1329 int ret = 0; 1330 1331 /* 1332 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. 1333 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does 1334 * support more than 8 LUNs. 1335 * Don't attempt if the target doesn't support REPORT LUNS. 1336 */ 1337 if (bflags & BLIST_NOREPORTLUN) 1338 return 1; 1339 if (starget->scsi_level < SCSI_2 && 1340 starget->scsi_level != SCSI_UNKNOWN) 1341 return 1; 1342 if (starget->scsi_level < SCSI_3 && 1343 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) 1344 return 1; 1345 if (bflags & BLIST_NOLUN) 1346 return 0; 1347 if (starget->no_report_luns) 1348 return 1; 1349 1350 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { 1351 sdev = scsi_alloc_sdev(starget, 0, NULL); 1352 if (!sdev) 1353 return 0; 1354 if (scsi_device_get(sdev)) { 1355 __scsi_remove_device(sdev); 1356 return 0; 1357 } 1358 } 1359 1360 /* 1361 * Allocate enough to hold the header (the same size as one scsi_lun) 1362 * plus the number of luns we are requesting. 511 was the default 1363 * value of the now removed max_report_luns parameter. 1364 */ 1365 length = (511 + 1) * sizeof(struct scsi_lun); 1366 retry: 1367 lun_data = kmalloc(length, GFP_KERNEL); 1368 if (!lun_data) { 1369 printk(ALLOC_FAILURE_MSG, __func__); 1370 goto out; 1371 } 1372 1373 scsi_cmd[0] = REPORT_LUNS; 1374 1375 /* 1376 * bytes 1 - 5: reserved, set to zero. 1377 */ 1378 memset(&scsi_cmd[1], 0, 5); 1379 1380 /* 1381 * bytes 6 - 9: length of the command. 1382 */ 1383 put_unaligned_be32(length, &scsi_cmd[6]); 1384 1385 scsi_cmd[10] = 0; /* reserved */ 1386 scsi_cmd[11] = 0; /* control */ 1387 1388 /* 1389 * We can get a UNIT ATTENTION, for example a power on/reset, so 1390 * retry a few times (like sd.c does for TEST UNIT READY). 1391 * Experience shows some combinations of adapter/devices get at 1392 * least two power on/resets. 1393 * 1394 * Illegal requests (for devices that do not support REPORT LUNS) 1395 * should come through as a check condition, and will not generate 1396 * a retry. 1397 */ 1398 for (retries = 0; retries < 3; retries++) { 1399 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1400 "scsi scan: Sending REPORT LUNS to (try %d)\n", 1401 retries)); 1402 1403 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 1404 lun_data, length, &sshdr, 1405 SCSI_REPORT_LUNS_TIMEOUT, 3, NULL); 1406 1407 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1408 "scsi scan: REPORT LUNS" 1409 " %s (try %d) result 0x%x\n", 1410 result ? "failed" : "successful", 1411 retries, result)); 1412 if (result == 0) 1413 break; 1414 else if (scsi_sense_valid(&sshdr)) { 1415 if (sshdr.sense_key != UNIT_ATTENTION) 1416 break; 1417 } 1418 } 1419 1420 if (result) { 1421 /* 1422 * The device probably does not support a REPORT LUN command 1423 */ 1424 ret = 1; 1425 goto out_err; 1426 } 1427 1428 /* 1429 * Get the length from the first four bytes of lun_data. 1430 */ 1431 if (get_unaligned_be32(lun_data->scsi_lun) + 1432 sizeof(struct scsi_lun) > length) { 1433 length = get_unaligned_be32(lun_data->scsi_lun) + 1434 sizeof(struct scsi_lun); 1435 kfree(lun_data); 1436 goto retry; 1437 } 1438 length = get_unaligned_be32(lun_data->scsi_lun); 1439 1440 num_luns = (length / sizeof(struct scsi_lun)); 1441 1442 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1443 "scsi scan: REPORT LUN scan\n")); 1444 1445 /* 1446 * Scan the luns in lun_data. The entry at offset 0 is really 1447 * the header, so start at 1 and go up to and including num_luns. 1448 */ 1449 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { 1450 lun = scsilun_to_int(lunp); 1451 1452 if (lun > sdev->host->max_lun) { 1453 sdev_printk(KERN_WARNING, sdev, 1454 "lun%llu has a LUN larger than" 1455 " allowed by the host adapter\n", lun); 1456 } else { 1457 int res; 1458 1459 res = scsi_probe_and_add_lun(starget, 1460 lun, NULL, NULL, rescan, NULL); 1461 if (res == SCSI_SCAN_NO_RESPONSE) { 1462 /* 1463 * Got some results, but now none, abort. 1464 */ 1465 sdev_printk(KERN_ERR, sdev, 1466 "Unexpected response" 1467 " from lun %llu while scanning, scan" 1468 " aborted\n", (unsigned long long)lun); 1469 break; 1470 } 1471 } 1472 } 1473 1474 out_err: 1475 kfree(lun_data); 1476 out: 1477 if (scsi_device_created(sdev)) 1478 /* 1479 * the sdev we used didn't appear in the report luns scan 1480 */ 1481 __scsi_remove_device(sdev); 1482 scsi_device_put(sdev); 1483 return ret; 1484 } 1485 1486 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, 1487 uint id, u64 lun, void *hostdata) 1488 { 1489 struct scsi_device *sdev = ERR_PTR(-ENODEV); 1490 struct device *parent = &shost->shost_gendev; 1491 struct scsi_target *starget; 1492 1493 if (strncmp(scsi_scan_type, "none", 4) == 0) 1494 return ERR_PTR(-ENODEV); 1495 1496 starget = scsi_alloc_target(parent, channel, id); 1497 if (!starget) 1498 return ERR_PTR(-ENOMEM); 1499 scsi_autopm_get_target(starget); 1500 1501 mutex_lock(&shost->scan_mutex); 1502 if (!shost->async_scan) 1503 scsi_complete_async_scans(); 1504 1505 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1506 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); 1507 scsi_autopm_put_host(shost); 1508 } 1509 mutex_unlock(&shost->scan_mutex); 1510 scsi_autopm_put_target(starget); 1511 /* 1512 * paired with scsi_alloc_target(). Target will be destroyed unless 1513 * scsi_probe_and_add_lun made an underlying device visible 1514 */ 1515 scsi_target_reap(starget); 1516 put_device(&starget->dev); 1517 1518 return sdev; 1519 } 1520 EXPORT_SYMBOL(__scsi_add_device); 1521 1522 int scsi_add_device(struct Scsi_Host *host, uint channel, 1523 uint target, u64 lun) 1524 { 1525 struct scsi_device *sdev = 1526 __scsi_add_device(host, channel, target, lun, NULL); 1527 if (IS_ERR(sdev)) 1528 return PTR_ERR(sdev); 1529 1530 scsi_device_put(sdev); 1531 return 0; 1532 } 1533 EXPORT_SYMBOL(scsi_add_device); 1534 1535 void scsi_rescan_device(struct device *dev) 1536 { 1537 struct scsi_device *sdev = to_scsi_device(dev); 1538 1539 device_lock(dev); 1540 1541 scsi_attach_vpd(sdev); 1542 1543 if (sdev->handler && sdev->handler->rescan) 1544 sdev->handler->rescan(sdev); 1545 1546 if (dev->driver && try_module_get(dev->driver->owner)) { 1547 struct scsi_driver *drv = to_scsi_driver(dev->driver); 1548 1549 if (drv->rescan) 1550 drv->rescan(dev); 1551 module_put(dev->driver->owner); 1552 } 1553 device_unlock(dev); 1554 } 1555 EXPORT_SYMBOL(scsi_rescan_device); 1556 1557 static void __scsi_scan_target(struct device *parent, unsigned int channel, 1558 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1559 { 1560 struct Scsi_Host *shost = dev_to_shost(parent); 1561 blist_flags_t bflags = 0; 1562 int res; 1563 struct scsi_target *starget; 1564 1565 if (shost->this_id == id) 1566 /* 1567 * Don't scan the host adapter 1568 */ 1569 return; 1570 1571 starget = scsi_alloc_target(parent, channel, id); 1572 if (!starget) 1573 return; 1574 scsi_autopm_get_target(starget); 1575 1576 if (lun != SCAN_WILD_CARD) { 1577 /* 1578 * Scan for a specific host/chan/id/lun. 1579 */ 1580 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); 1581 goto out_reap; 1582 } 1583 1584 /* 1585 * Scan LUN 0, if there is some response, scan further. Ideally, we 1586 * would not configure LUN 0 until all LUNs are scanned. 1587 */ 1588 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); 1589 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { 1590 if (scsi_report_lun_scan(starget, bflags, rescan) != 0) 1591 /* 1592 * The REPORT LUN did not scan the target, 1593 * do a sequential scan. 1594 */ 1595 scsi_sequential_lun_scan(starget, bflags, 1596 starget->scsi_level, rescan); 1597 } 1598 1599 out_reap: 1600 scsi_autopm_put_target(starget); 1601 /* 1602 * paired with scsi_alloc_target(): determine if the target has 1603 * any children at all and if not, nuke it 1604 */ 1605 scsi_target_reap(starget); 1606 1607 put_device(&starget->dev); 1608 } 1609 1610 /** 1611 * scsi_scan_target - scan a target id, possibly including all LUNs on the target. 1612 * @parent: host to scan 1613 * @channel: channel to scan 1614 * @id: target id to scan 1615 * @lun: Specific LUN to scan or SCAN_WILD_CARD 1616 * @rescan: passed to LUN scanning routines; SCSI_SCAN_INITIAL for 1617 * no rescan, SCSI_SCAN_RESCAN to rescan existing LUNs, 1618 * and SCSI_SCAN_MANUAL to force scanning even if 1619 * 'scan=manual' is set. 1620 * 1621 * Description: 1622 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, 1623 * and possibly all LUNs on the target id. 1624 * 1625 * First try a REPORT LUN scan, if that does not scan the target, do a 1626 * sequential scan of LUNs on the target id. 1627 **/ 1628 void scsi_scan_target(struct device *parent, unsigned int channel, 1629 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1630 { 1631 struct Scsi_Host *shost = dev_to_shost(parent); 1632 1633 if (strncmp(scsi_scan_type, "none", 4) == 0) 1634 return; 1635 1636 if (rescan != SCSI_SCAN_MANUAL && 1637 strncmp(scsi_scan_type, "manual", 6) == 0) 1638 return; 1639 1640 mutex_lock(&shost->scan_mutex); 1641 if (!shost->async_scan) 1642 scsi_complete_async_scans(); 1643 1644 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1645 __scsi_scan_target(parent, channel, id, lun, rescan); 1646 scsi_autopm_put_host(shost); 1647 } 1648 mutex_unlock(&shost->scan_mutex); 1649 } 1650 EXPORT_SYMBOL(scsi_scan_target); 1651 1652 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, 1653 unsigned int id, u64 lun, 1654 enum scsi_scan_mode rescan) 1655 { 1656 uint order_id; 1657 1658 if (id == SCAN_WILD_CARD) 1659 for (id = 0; id < shost->max_id; ++id) { 1660 /* 1661 * XXX adapter drivers when possible (FCP, iSCSI) 1662 * could modify max_id to match the current max, 1663 * not the absolute max. 1664 * 1665 * XXX add a shost id iterator, so for example, 1666 * the FC ID can be the same as a target id 1667 * without a huge overhead of sparse id's. 1668 */ 1669 if (shost->reverse_ordering) 1670 /* 1671 * Scan from high to low id. 1672 */ 1673 order_id = shost->max_id - id - 1; 1674 else 1675 order_id = id; 1676 __scsi_scan_target(&shost->shost_gendev, channel, 1677 order_id, lun, rescan); 1678 } 1679 else 1680 __scsi_scan_target(&shost->shost_gendev, channel, 1681 id, lun, rescan); 1682 } 1683 1684 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, 1685 unsigned int id, u64 lun, 1686 enum scsi_scan_mode rescan) 1687 { 1688 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, 1689 "%s: <%u:%u:%llu>\n", 1690 __func__, channel, id, lun)); 1691 1692 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || 1693 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || 1694 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun))) 1695 return -EINVAL; 1696 1697 mutex_lock(&shost->scan_mutex); 1698 if (!shost->async_scan) 1699 scsi_complete_async_scans(); 1700 1701 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1702 if (channel == SCAN_WILD_CARD) 1703 for (channel = 0; channel <= shost->max_channel; 1704 channel++) 1705 scsi_scan_channel(shost, channel, id, lun, 1706 rescan); 1707 else 1708 scsi_scan_channel(shost, channel, id, lun, rescan); 1709 scsi_autopm_put_host(shost); 1710 } 1711 mutex_unlock(&shost->scan_mutex); 1712 1713 return 0; 1714 } 1715 1716 static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 1717 { 1718 struct scsi_device *sdev; 1719 shost_for_each_device(sdev, shost) { 1720 /* target removed before the device could be added */ 1721 if (sdev->sdev_state == SDEV_DEL) 1722 continue; 1723 /* If device is already visible, skip adding it to sysfs */ 1724 if (sdev->is_visible) 1725 continue; 1726 if (!scsi_host_scan_allowed(shost) || 1727 scsi_sysfs_add_sdev(sdev) != 0) 1728 __scsi_remove_device(sdev); 1729 } 1730 } 1731 1732 /** 1733 * scsi_prep_async_scan - prepare for an async scan 1734 * @shost: the host which will be scanned 1735 * Returns: a cookie to be passed to scsi_finish_async_scan() 1736 * 1737 * Tells the midlayer this host is going to do an asynchronous scan. 1738 * It reserves the host's position in the scanning list and ensures 1739 * that other asynchronous scans started after this one won't affect the 1740 * ordering of the discovered devices. 1741 */ 1742 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 1743 { 1744 struct async_scan_data *data = NULL; 1745 unsigned long flags; 1746 1747 if (strncmp(scsi_scan_type, "sync", 4) == 0) 1748 return NULL; 1749 1750 mutex_lock(&shost->scan_mutex); 1751 if (shost->async_scan) { 1752 shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__); 1753 goto err; 1754 } 1755 1756 data = kmalloc(sizeof(*data), GFP_KERNEL); 1757 if (!data) 1758 goto err; 1759 data->shost = scsi_host_get(shost); 1760 if (!data->shost) 1761 goto err; 1762 init_completion(&data->prev_finished); 1763 1764 spin_lock_irqsave(shost->host_lock, flags); 1765 shost->async_scan = 1; 1766 spin_unlock_irqrestore(shost->host_lock, flags); 1767 mutex_unlock(&shost->scan_mutex); 1768 1769 spin_lock(&async_scan_lock); 1770 if (list_empty(&scanning_hosts)) 1771 complete(&data->prev_finished); 1772 list_add_tail(&data->list, &scanning_hosts); 1773 spin_unlock(&async_scan_lock); 1774 1775 return data; 1776 1777 err: 1778 mutex_unlock(&shost->scan_mutex); 1779 kfree(data); 1780 return NULL; 1781 } 1782 1783 /** 1784 * scsi_finish_async_scan - asynchronous scan has finished 1785 * @data: cookie returned from earlier call to scsi_prep_async_scan() 1786 * 1787 * All the devices currently attached to this host have been found. 1788 * This function announces all the devices it has found to the rest 1789 * of the system. 1790 */ 1791 static void scsi_finish_async_scan(struct async_scan_data *data) 1792 { 1793 struct Scsi_Host *shost; 1794 unsigned long flags; 1795 1796 if (!data) 1797 return; 1798 1799 shost = data->shost; 1800 1801 mutex_lock(&shost->scan_mutex); 1802 1803 if (!shost->async_scan) { 1804 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1805 dump_stack(); 1806 mutex_unlock(&shost->scan_mutex); 1807 return; 1808 } 1809 1810 wait_for_completion(&data->prev_finished); 1811 1812 scsi_sysfs_add_devices(shost); 1813 1814 spin_lock_irqsave(shost->host_lock, flags); 1815 shost->async_scan = 0; 1816 spin_unlock_irqrestore(shost->host_lock, flags); 1817 1818 mutex_unlock(&shost->scan_mutex); 1819 1820 spin_lock(&async_scan_lock); 1821 list_del(&data->list); 1822 if (!list_empty(&scanning_hosts)) { 1823 struct async_scan_data *next = list_entry(scanning_hosts.next, 1824 struct async_scan_data, list); 1825 complete(&next->prev_finished); 1826 } 1827 spin_unlock(&async_scan_lock); 1828 1829 scsi_autopm_put_host(shost); 1830 scsi_host_put(shost); 1831 kfree(data); 1832 } 1833 1834 static void do_scsi_scan_host(struct Scsi_Host *shost) 1835 { 1836 if (shost->hostt->scan_finished) { 1837 unsigned long start = jiffies; 1838 if (shost->hostt->scan_start) 1839 shost->hostt->scan_start(shost); 1840 1841 while (!shost->hostt->scan_finished(shost, jiffies - start)) 1842 msleep(10); 1843 } else { 1844 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, 1845 SCAN_WILD_CARD, 0); 1846 } 1847 } 1848 1849 static void do_scan_async(void *_data, async_cookie_t c) 1850 { 1851 struct async_scan_data *data = _data; 1852 struct Scsi_Host *shost = data->shost; 1853 1854 do_scsi_scan_host(shost); 1855 scsi_finish_async_scan(data); 1856 } 1857 1858 /** 1859 * scsi_scan_host - scan the given adapter 1860 * @shost: adapter to scan 1861 **/ 1862 void scsi_scan_host(struct Scsi_Host *shost) 1863 { 1864 struct async_scan_data *data; 1865 1866 if (strncmp(scsi_scan_type, "none", 4) == 0 || 1867 strncmp(scsi_scan_type, "manual", 6) == 0) 1868 return; 1869 if (scsi_autopm_get_host(shost) < 0) 1870 return; 1871 1872 data = scsi_prep_async_scan(shost); 1873 if (!data) { 1874 do_scsi_scan_host(shost); 1875 scsi_autopm_put_host(shost); 1876 return; 1877 } 1878 1879 /* register with the async subsystem so wait_for_device_probe() 1880 * will flush this work 1881 */ 1882 async_schedule(do_scan_async, data); 1883 1884 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */ 1885 } 1886 EXPORT_SYMBOL(scsi_scan_host); 1887 1888 void scsi_forget_host(struct Scsi_Host *shost) 1889 { 1890 struct scsi_device *sdev; 1891 unsigned long flags; 1892 1893 restart: 1894 spin_lock_irqsave(shost->host_lock, flags); 1895 list_for_each_entry(sdev, &shost->__devices, siblings) { 1896 if (sdev->sdev_state == SDEV_DEL) 1897 continue; 1898 spin_unlock_irqrestore(shost->host_lock, flags); 1899 __scsi_remove_device(sdev); 1900 goto restart; 1901 } 1902 spin_unlock_irqrestore(shost->host_lock, flags); 1903 } 1904 1905 /** 1906 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself 1907 * @shost: Host that needs a scsi_device 1908 * 1909 * Lock status: None assumed. 1910 * 1911 * Returns: The scsi_device or NULL 1912 * 1913 * Notes: 1914 * Attach a single scsi_device to the Scsi_Host - this should 1915 * be made to look like a "pseudo-device" that points to the 1916 * HA itself. 1917 * 1918 * Note - this device is not accessible from any high-level 1919 * drivers (including generics), which is probably not 1920 * optimal. We can add hooks later to attach. 1921 */ 1922 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) 1923 { 1924 struct scsi_device *sdev = NULL; 1925 struct scsi_target *starget; 1926 1927 mutex_lock(&shost->scan_mutex); 1928 if (!scsi_host_scan_allowed(shost)) 1929 goto out; 1930 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); 1931 if (!starget) 1932 goto out; 1933 1934 sdev = scsi_alloc_sdev(starget, 0, NULL); 1935 if (sdev) 1936 sdev->borken = 0; 1937 else 1938 scsi_target_reap(starget); 1939 put_device(&starget->dev); 1940 out: 1941 mutex_unlock(&shost->scan_mutex); 1942 return sdev; 1943 } 1944 EXPORT_SYMBOL(scsi_get_host_dev); 1945 1946 /** 1947 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself 1948 * @sdev: Host device to be freed 1949 * 1950 * Lock status: None assumed. 1951 * 1952 * Returns: Nothing 1953 */ 1954 void scsi_free_host_dev(struct scsi_device *sdev) 1955 { 1956 BUG_ON(sdev->id != sdev->host->this_id); 1957 1958 __scsi_remove_device(sdev); 1959 } 1960 EXPORT_SYMBOL(scsi_free_host_dev); 1961 1962