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 static 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_enable_async_suspend - Enable async suspend and resume 127 */ 128 void scsi_enable_async_suspend(struct device *dev) 129 { 130 /* 131 * If a user has disabled async probing a likely reason is due to a 132 * storage enclosure that does not inject staggered spin-ups. For 133 * safety, make resume synchronous as well in that case. 134 */ 135 if (strncmp(scsi_scan_type, "async", 5) != 0) 136 return; 137 /* Enable asynchronous suspend and resume. */ 138 device_enable_async_suspend(dev); 139 } 140 141 /** 142 * scsi_complete_async_scans - Wait for asynchronous scans to complete 143 * 144 * When this function returns, any host which started scanning before 145 * this function was called will have finished its scan. Hosts which 146 * started scanning after this function was called may or may not have 147 * finished. 148 */ 149 int scsi_complete_async_scans(void) 150 { 151 struct async_scan_data *data; 152 153 do { 154 if (list_empty(&scanning_hosts)) 155 return 0; 156 /* If we can't get memory immediately, that's OK. Just 157 * sleep a little. Even if we never get memory, the async 158 * scans will finish eventually. 159 */ 160 data = kmalloc(sizeof(*data), GFP_KERNEL); 161 if (!data) 162 msleep(1); 163 } while (!data); 164 165 data->shost = NULL; 166 init_completion(&data->prev_finished); 167 168 spin_lock(&async_scan_lock); 169 /* Check that there's still somebody else on the list */ 170 if (list_empty(&scanning_hosts)) 171 goto done; 172 list_add_tail(&data->list, &scanning_hosts); 173 spin_unlock(&async_scan_lock); 174 175 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); 176 wait_for_completion(&data->prev_finished); 177 178 spin_lock(&async_scan_lock); 179 list_del(&data->list); 180 if (!list_empty(&scanning_hosts)) { 181 struct async_scan_data *next = list_entry(scanning_hosts.next, 182 struct async_scan_data, list); 183 complete(&next->prev_finished); 184 } 185 done: 186 spin_unlock(&async_scan_lock); 187 188 kfree(data); 189 return 0; 190 } 191 192 /** 193 * scsi_unlock_floptical - unlock device via a special MODE SENSE command 194 * @sdev: scsi device to send command to 195 * @result: area to store the result of the MODE SENSE 196 * 197 * Description: 198 * Send a vendor specific MODE SENSE (not a MODE SELECT) command. 199 * Called for BLIST_KEY devices. 200 **/ 201 static void scsi_unlock_floptical(struct scsi_device *sdev, 202 unsigned char *result) 203 { 204 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 205 206 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n"); 207 scsi_cmd[0] = MODE_SENSE; 208 scsi_cmd[1] = 0; 209 scsi_cmd[2] = 0x2e; 210 scsi_cmd[3] = 0; 211 scsi_cmd[4] = 0x2a; /* size */ 212 scsi_cmd[5] = 0; 213 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, 214 SCSI_TIMEOUT, 3, NULL); 215 } 216 217 static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev, 218 unsigned int depth) 219 { 220 int new_shift = sbitmap_calculate_shift(depth); 221 bool need_alloc = !sdev->budget_map.map; 222 bool need_free = false; 223 int ret; 224 struct sbitmap sb_backup; 225 226 depth = min_t(unsigned int, depth, scsi_device_max_queue_depth(sdev)); 227 228 /* 229 * realloc if new shift is calculated, which is caused by setting 230 * up one new default queue depth after calling ->slave_configure 231 */ 232 if (!need_alloc && new_shift != sdev->budget_map.shift) 233 need_alloc = need_free = true; 234 235 if (!need_alloc) 236 return 0; 237 238 /* 239 * Request queue has to be frozen for reallocating budget map, 240 * and here disk isn't added yet, so freezing is pretty fast 241 */ 242 if (need_free) { 243 blk_mq_freeze_queue(sdev->request_queue); 244 sb_backup = sdev->budget_map; 245 } 246 ret = sbitmap_init_node(&sdev->budget_map, 247 scsi_device_max_queue_depth(sdev), 248 new_shift, GFP_KERNEL, 249 sdev->request_queue->node, false, true); 250 if (!ret) 251 sbitmap_resize(&sdev->budget_map, depth); 252 253 if (need_free) { 254 if (ret) 255 sdev->budget_map = sb_backup; 256 else 257 sbitmap_free(&sb_backup); 258 ret = 0; 259 blk_mq_unfreeze_queue(sdev->request_queue); 260 } 261 return ret; 262 } 263 264 /** 265 * scsi_alloc_sdev - allocate and setup a scsi_Device 266 * @starget: which target to allocate a &scsi_device for 267 * @lun: which lun 268 * @hostdata: usually NULL and set by ->slave_alloc instead 269 * 270 * Description: 271 * Allocate, initialize for io, and return a pointer to a scsi_Device. 272 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and 273 * adds scsi_Device to the appropriate list. 274 * 275 * Return value: 276 * scsi_Device pointer, or NULL on failure. 277 **/ 278 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, 279 u64 lun, void *hostdata) 280 { 281 unsigned int depth; 282 struct scsi_device *sdev; 283 struct request_queue *q; 284 int display_failure_msg = 1, ret; 285 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 286 287 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, 288 GFP_KERNEL); 289 if (!sdev) 290 goto out; 291 292 sdev->vendor = scsi_null_device_strs; 293 sdev->model = scsi_null_device_strs; 294 sdev->rev = scsi_null_device_strs; 295 sdev->host = shost; 296 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD; 297 sdev->id = starget->id; 298 sdev->lun = lun; 299 sdev->channel = starget->channel; 300 mutex_init(&sdev->state_mutex); 301 sdev->sdev_state = SDEV_CREATED; 302 INIT_LIST_HEAD(&sdev->siblings); 303 INIT_LIST_HEAD(&sdev->same_target_siblings); 304 INIT_LIST_HEAD(&sdev->starved_entry); 305 INIT_LIST_HEAD(&sdev->event_list); 306 spin_lock_init(&sdev->list_lock); 307 mutex_init(&sdev->inquiry_mutex); 308 INIT_WORK(&sdev->event_work, scsi_evt_thread); 309 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue); 310 311 sdev->sdev_gendev.parent = get_device(&starget->dev); 312 sdev->sdev_target = starget; 313 314 /* usually NULL and set by ->slave_alloc instead */ 315 sdev->hostdata = hostdata; 316 317 /* if the device needs this changing, it may do so in the 318 * slave_configure function */ 319 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; 320 321 /* 322 * Some low level driver could use device->type 323 */ 324 sdev->type = -1; 325 326 /* 327 * Assume that the device will have handshaking problems, 328 * and then fix this field later if it turns out it 329 * doesn't 330 */ 331 sdev->borken = 1; 332 333 sdev->sg_reserved_size = INT_MAX; 334 335 q = blk_mq_init_queue(&sdev->host->tag_set); 336 if (IS_ERR(q)) { 337 /* release fn is set up in scsi_sysfs_device_initialise, so 338 * have to free and put manually here */ 339 put_device(&starget->dev); 340 kfree(sdev); 341 goto out; 342 } 343 kref_get(&sdev->host->tagset_refcnt); 344 sdev->request_queue = q; 345 q->queuedata = sdev; 346 __scsi_init_queue(sdev->host, q); 347 WARN_ON_ONCE(!blk_get_queue(q)); 348 349 depth = sdev->host->cmd_per_lun ?: 1; 350 351 /* 352 * Use .can_queue as budget map's depth because we have to 353 * support adjusting queue depth from sysfs. Meantime use 354 * default device queue depth to figure out sbitmap shift 355 * since we use this queue depth most of times. 356 */ 357 if (scsi_realloc_sdev_budget_map(sdev, depth)) { 358 put_device(&starget->dev); 359 kfree(sdev); 360 goto out; 361 } 362 363 scsi_change_queue_depth(sdev, depth); 364 365 scsi_sysfs_device_initialize(sdev); 366 367 if (shost->hostt->slave_alloc) { 368 ret = shost->hostt->slave_alloc(sdev); 369 if (ret) { 370 /* 371 * if LLDD reports slave not present, don't clutter 372 * console with alloc failure messages 373 */ 374 if (ret == -ENXIO) 375 display_failure_msg = 0; 376 goto out_device_destroy; 377 } 378 } 379 380 return sdev; 381 382 out_device_destroy: 383 __scsi_remove_device(sdev); 384 out: 385 if (display_failure_msg) 386 printk(ALLOC_FAILURE_MSG, __func__); 387 return NULL; 388 } 389 390 static void scsi_target_destroy(struct scsi_target *starget) 391 { 392 struct device *dev = &starget->dev; 393 struct Scsi_Host *shost = dev_to_shost(dev->parent); 394 unsigned long flags; 395 396 BUG_ON(starget->state == STARGET_DEL); 397 starget->state = STARGET_DEL; 398 transport_destroy_device(dev); 399 spin_lock_irqsave(shost->host_lock, flags); 400 if (shost->hostt->target_destroy) 401 shost->hostt->target_destroy(starget); 402 list_del_init(&starget->siblings); 403 spin_unlock_irqrestore(shost->host_lock, flags); 404 put_device(dev); 405 } 406 407 static void scsi_target_dev_release(struct device *dev) 408 { 409 struct device *parent = dev->parent; 410 struct scsi_target *starget = to_scsi_target(dev); 411 412 kfree(starget); 413 put_device(parent); 414 } 415 416 static struct device_type scsi_target_type = { 417 .name = "scsi_target", 418 .release = scsi_target_dev_release, 419 }; 420 421 int scsi_is_target_device(const struct device *dev) 422 { 423 return dev->type == &scsi_target_type; 424 } 425 EXPORT_SYMBOL(scsi_is_target_device); 426 427 static struct scsi_target *__scsi_find_target(struct device *parent, 428 int channel, uint id) 429 { 430 struct scsi_target *starget, *found_starget = NULL; 431 struct Scsi_Host *shost = dev_to_shost(parent); 432 /* 433 * Search for an existing target for this sdev. 434 */ 435 list_for_each_entry(starget, &shost->__targets, siblings) { 436 if (starget->id == id && 437 starget->channel == channel) { 438 found_starget = starget; 439 break; 440 } 441 } 442 if (found_starget) 443 get_device(&found_starget->dev); 444 445 return found_starget; 446 } 447 448 /** 449 * scsi_target_reap_ref_release - remove target from visibility 450 * @kref: the reap_ref in the target being released 451 * 452 * Called on last put of reap_ref, which is the indication that no device 453 * under this target is visible anymore, so render the target invisible in 454 * sysfs. Note: we have to be in user context here because the target reaps 455 * should be done in places where the scsi device visibility is being removed. 456 */ 457 static void scsi_target_reap_ref_release(struct kref *kref) 458 { 459 struct scsi_target *starget 460 = container_of(kref, struct scsi_target, reap_ref); 461 462 /* 463 * if we get here and the target is still in a CREATED state that 464 * means it was allocated but never made visible (because a scan 465 * turned up no LUNs), so don't call device_del() on it. 466 */ 467 if ((starget->state != STARGET_CREATED) && 468 (starget->state != STARGET_CREATED_REMOVE)) { 469 transport_remove_device(&starget->dev); 470 device_del(&starget->dev); 471 } 472 scsi_target_destroy(starget); 473 } 474 475 static void scsi_target_reap_ref_put(struct scsi_target *starget) 476 { 477 kref_put(&starget->reap_ref, scsi_target_reap_ref_release); 478 } 479 480 /** 481 * scsi_alloc_target - allocate a new or find an existing target 482 * @parent: parent of the target (need not be a scsi host) 483 * @channel: target channel number (zero if no channels) 484 * @id: target id number 485 * 486 * Return an existing target if one exists, provided it hasn't already 487 * gone into STARGET_DEL state, otherwise allocate a new target. 488 * 489 * The target is returned with an incremented reference, so the caller 490 * is responsible for both reaping and doing a last put 491 */ 492 static struct scsi_target *scsi_alloc_target(struct device *parent, 493 int channel, uint id) 494 { 495 struct Scsi_Host *shost = dev_to_shost(parent); 496 struct device *dev = NULL; 497 unsigned long flags; 498 const int size = sizeof(struct scsi_target) 499 + shost->transportt->target_size; 500 struct scsi_target *starget; 501 struct scsi_target *found_target; 502 int error, ref_got; 503 504 starget = kzalloc(size, GFP_KERNEL); 505 if (!starget) { 506 printk(KERN_ERR "%s: allocation failure\n", __func__); 507 return NULL; 508 } 509 dev = &starget->dev; 510 device_initialize(dev); 511 kref_init(&starget->reap_ref); 512 dev->parent = get_device(parent); 513 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); 514 dev->bus = &scsi_bus_type; 515 dev->type = &scsi_target_type; 516 scsi_enable_async_suspend(dev); 517 starget->id = id; 518 starget->channel = channel; 519 starget->can_queue = 0; 520 INIT_LIST_HEAD(&starget->siblings); 521 INIT_LIST_HEAD(&starget->devices); 522 starget->state = STARGET_CREATED; 523 starget->scsi_level = SCSI_2; 524 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; 525 retry: 526 spin_lock_irqsave(shost->host_lock, flags); 527 528 found_target = __scsi_find_target(parent, channel, id); 529 if (found_target) 530 goto found; 531 532 list_add_tail(&starget->siblings, &shost->__targets); 533 spin_unlock_irqrestore(shost->host_lock, flags); 534 /* allocate and add */ 535 transport_setup_device(dev); 536 if (shost->hostt->target_alloc) { 537 error = shost->hostt->target_alloc(starget); 538 539 if(error) { 540 if (error != -ENXIO) 541 dev_err(dev, "target allocation failed, error %d\n", error); 542 /* don't want scsi_target_reap to do the final 543 * put because it will be under the host lock */ 544 scsi_target_destroy(starget); 545 return NULL; 546 } 547 } 548 get_device(dev); 549 550 return starget; 551 552 found: 553 /* 554 * release routine already fired if kref is zero, so if we can still 555 * take the reference, the target must be alive. If we can't, it must 556 * be dying and we need to wait for a new target 557 */ 558 ref_got = kref_get_unless_zero(&found_target->reap_ref); 559 560 spin_unlock_irqrestore(shost->host_lock, flags); 561 if (ref_got) { 562 put_device(dev); 563 return found_target; 564 } 565 /* 566 * Unfortunately, we found a dying target; need to wait until it's 567 * dead before we can get a new one. There is an anomaly here. We 568 * *should* call scsi_target_reap() to balance the kref_get() of the 569 * reap_ref above. However, since the target being released, it's 570 * already invisible and the reap_ref is irrelevant. If we call 571 * scsi_target_reap() we might spuriously do another device_del() on 572 * an already invisible target. 573 */ 574 put_device(&found_target->dev); 575 /* 576 * length of time is irrelevant here, we just want to yield the CPU 577 * for a tick to avoid busy waiting for the target to die. 578 */ 579 msleep(1); 580 goto retry; 581 } 582 583 /** 584 * scsi_target_reap - check to see if target is in use and destroy if not 585 * @starget: target to be checked 586 * 587 * This is used after removing a LUN or doing a last put of the target 588 * it checks atomically that nothing is using the target and removes 589 * it if so. 590 */ 591 void scsi_target_reap(struct scsi_target *starget) 592 { 593 /* 594 * serious problem if this triggers: STARGET_DEL is only set in the if 595 * the reap_ref drops to zero, so we're trying to do another final put 596 * on an already released kref 597 */ 598 BUG_ON(starget->state == STARGET_DEL); 599 scsi_target_reap_ref_put(starget); 600 } 601 602 /** 603 * scsi_sanitize_inquiry_string - remove non-graphical chars from an 604 * INQUIRY result string 605 * @s: INQUIRY result string to sanitize 606 * @len: length of the string 607 * 608 * Description: 609 * The SCSI spec says that INQUIRY vendor, product, and revision 610 * strings must consist entirely of graphic ASCII characters, 611 * padded on the right with spaces. Since not all devices obey 612 * this rule, we will replace non-graphic or non-ASCII characters 613 * with spaces. Exception: a NUL character is interpreted as a 614 * string terminator, so all the following characters are set to 615 * spaces. 616 **/ 617 void scsi_sanitize_inquiry_string(unsigned char *s, int len) 618 { 619 int terminated = 0; 620 621 for (; len > 0; (--len, ++s)) { 622 if (*s == 0) 623 terminated = 1; 624 if (terminated || *s < 0x20 || *s > 0x7e) 625 *s = ' '; 626 } 627 } 628 EXPORT_SYMBOL(scsi_sanitize_inquiry_string); 629 630 /** 631 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY 632 * @sdev: scsi_device to probe 633 * @inq_result: area to store the INQUIRY result 634 * @result_len: len of inq_result 635 * @bflags: store any bflags found here 636 * 637 * Description: 638 * Probe the lun associated with @req using a standard SCSI INQUIRY; 639 * 640 * If the INQUIRY is successful, zero is returned and the 641 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length 642 * are copied to the scsi_device any flags value is stored in *@bflags. 643 **/ 644 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, 645 int result_len, blist_flags_t *bflags) 646 { 647 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 648 int first_inquiry_len, try_inquiry_len, next_inquiry_len; 649 int response_len = 0; 650 int pass, count, result; 651 struct scsi_sense_hdr sshdr; 652 653 *bflags = 0; 654 655 /* Perform up to 3 passes. The first pass uses a conservative 656 * transfer length of 36 unless sdev->inquiry_len specifies a 657 * different value. */ 658 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; 659 try_inquiry_len = first_inquiry_len; 660 pass = 1; 661 662 next_pass: 663 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 664 "scsi scan: INQUIRY pass %d length %d\n", 665 pass, try_inquiry_len)); 666 667 /* Each pass gets up to three chances to ignore Unit Attention */ 668 for (count = 0; count < 3; ++count) { 669 int resid; 670 671 memset(scsi_cmd, 0, 6); 672 scsi_cmd[0] = INQUIRY; 673 scsi_cmd[4] = (unsigned char) try_inquiry_len; 674 675 memset(inq_result, 0, try_inquiry_len); 676 677 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 678 inq_result, try_inquiry_len, &sshdr, 679 HZ / 2 + HZ * scsi_inq_timeout, 3, 680 &resid); 681 682 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 683 "scsi scan: INQUIRY %s with code 0x%x\n", 684 result ? "failed" : "successful", result)); 685 686 if (result > 0) { 687 /* 688 * not-ready to ready transition [asc/ascq=0x28/0x0] 689 * or power-on, reset [asc/ascq=0x29/0x0], continue. 690 * INQUIRY should not yield UNIT_ATTENTION 691 * but many buggy devices do so anyway. 692 */ 693 if (scsi_status_is_check_condition(result) && 694 scsi_sense_valid(&sshdr)) { 695 if ((sshdr.sense_key == UNIT_ATTENTION) && 696 ((sshdr.asc == 0x28) || 697 (sshdr.asc == 0x29)) && 698 (sshdr.ascq == 0)) 699 continue; 700 } 701 } else if (result == 0) { 702 /* 703 * if nothing was transferred, we try 704 * again. It's a workaround for some USB 705 * devices. 706 */ 707 if (resid == try_inquiry_len) 708 continue; 709 } 710 break; 711 } 712 713 if (result == 0) { 714 scsi_sanitize_inquiry_string(&inq_result[8], 8); 715 scsi_sanitize_inquiry_string(&inq_result[16], 16); 716 scsi_sanitize_inquiry_string(&inq_result[32], 4); 717 718 response_len = inq_result[4] + 5; 719 if (response_len > 255) 720 response_len = first_inquiry_len; /* sanity */ 721 722 /* 723 * Get any flags for this device. 724 * 725 * XXX add a bflags to scsi_device, and replace the 726 * corresponding bit fields in scsi_device, so bflags 727 * need not be passed as an argument. 728 */ 729 *bflags = scsi_get_device_flags(sdev, &inq_result[8], 730 &inq_result[16]); 731 732 /* When the first pass succeeds we gain information about 733 * what larger transfer lengths might work. */ 734 if (pass == 1) { 735 if (BLIST_INQUIRY_36 & *bflags) 736 next_inquiry_len = 36; 737 /* 738 * LLD specified a maximum sdev->inquiry_len 739 * but device claims it has more data. Capping 740 * the length only makes sense for legacy 741 * devices. If a device supports SPC-4 (2014) 742 * or newer, assume that it is safe to ask for 743 * as much as the device says it supports. 744 */ 745 else if (sdev->inquiry_len && 746 response_len > sdev->inquiry_len && 747 (inq_result[2] & 0x7) < 6) /* SPC-4 */ 748 next_inquiry_len = sdev->inquiry_len; 749 else 750 next_inquiry_len = response_len; 751 752 /* If more data is available perform the second pass */ 753 if (next_inquiry_len > try_inquiry_len) { 754 try_inquiry_len = next_inquiry_len; 755 pass = 2; 756 goto next_pass; 757 } 758 } 759 760 } else if (pass == 2) { 761 sdev_printk(KERN_INFO, sdev, 762 "scsi scan: %d byte inquiry failed. " 763 "Consider BLIST_INQUIRY_36 for this device\n", 764 try_inquiry_len); 765 766 /* If this pass failed, the third pass goes back and transfers 767 * the same amount as we successfully got in the first pass. */ 768 try_inquiry_len = first_inquiry_len; 769 pass = 3; 770 goto next_pass; 771 } 772 773 /* If the last transfer attempt got an error, assume the 774 * peripheral doesn't exist or is dead. */ 775 if (result) 776 return -EIO; 777 778 /* Don't report any more data than the device says is valid */ 779 sdev->inquiry_len = min(try_inquiry_len, response_len); 780 781 /* 782 * XXX Abort if the response length is less than 36? If less than 783 * 32, the lookup of the device flags (above) could be invalid, 784 * and it would be possible to take an incorrect action - we do 785 * not want to hang because of a short INQUIRY. On the flip side, 786 * if the device is spun down or becoming ready (and so it gives a 787 * short INQUIRY), an abort here prevents any further use of the 788 * device, including spin up. 789 * 790 * On the whole, the best approach seems to be to assume the first 791 * 36 bytes are valid no matter what the device says. That's 792 * better than copying < 36 bytes to the inquiry-result buffer 793 * and displaying garbage for the Vendor, Product, or Revision 794 * strings. 795 */ 796 if (sdev->inquiry_len < 36) { 797 if (!sdev->host->short_inquiry) { 798 shost_printk(KERN_INFO, sdev->host, 799 "scsi scan: INQUIRY result too short (%d)," 800 " using 36\n", sdev->inquiry_len); 801 sdev->host->short_inquiry = 1; 802 } 803 sdev->inquiry_len = 36; 804 } 805 806 /* 807 * Related to the above issue: 808 * 809 * XXX Devices (disk or all?) should be sent a TEST UNIT READY, 810 * and if not ready, sent a START_STOP to start (maybe spin up) and 811 * then send the INQUIRY again, since the INQUIRY can change after 812 * a device is initialized. 813 * 814 * Ideally, start a device if explicitly asked to do so. This 815 * assumes that a device is spun up on power on, spun down on 816 * request, and then spun up on request. 817 */ 818 819 /* 820 * The scanning code needs to know the scsi_level, even if no 821 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so 822 * non-zero LUNs can be scanned. 823 */ 824 sdev->scsi_level = inq_result[2] & 0x07; 825 if (sdev->scsi_level >= 2 || 826 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) 827 sdev->scsi_level++; 828 sdev->sdev_target->scsi_level = sdev->scsi_level; 829 830 /* 831 * If SCSI-2 or lower, and if the transport requires it, 832 * store the LUN value in CDB[1]. 833 */ 834 sdev->lun_in_cdb = 0; 835 if (sdev->scsi_level <= SCSI_2 && 836 sdev->scsi_level != SCSI_UNKNOWN && 837 !sdev->host->no_scsi2_lun_in_cdb) 838 sdev->lun_in_cdb = 1; 839 840 return 0; 841 } 842 843 /** 844 * scsi_add_lun - allocate and fully initialze a scsi_device 845 * @sdev: holds information to be stored in the new scsi_device 846 * @inq_result: holds the result of a previous INQUIRY to the LUN 847 * @bflags: black/white list flag 848 * @async: 1 if this device is being scanned asynchronously 849 * 850 * Description: 851 * Initialize the scsi_device @sdev. Optionally set fields based 852 * on values in *@bflags. 853 * 854 * Return: 855 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 856 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 857 **/ 858 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, 859 blist_flags_t *bflags, int async) 860 { 861 int ret; 862 863 /* 864 * XXX do not save the inquiry, since it can change underneath us, 865 * save just vendor/model/rev. 866 * 867 * Rather than save it and have an ioctl that retrieves the saved 868 * value, have an ioctl that executes the same INQUIRY code used 869 * in scsi_probe_lun, let user level programs doing INQUIRY 870 * scanning run at their own risk, or supply a user level program 871 * that can correctly scan. 872 */ 873 874 /* 875 * Copy at least 36 bytes of INQUIRY data, so that we don't 876 * dereference unallocated memory when accessing the Vendor, 877 * Product, and Revision strings. Badly behaved devices may set 878 * the INQUIRY Additional Length byte to a small value, indicating 879 * these strings are invalid, but often they contain plausible data 880 * nonetheless. It doesn't matter if the device sent < 36 bytes 881 * total, since scsi_probe_lun() initializes inq_result with 0s. 882 */ 883 sdev->inquiry = kmemdup(inq_result, 884 max_t(size_t, sdev->inquiry_len, 36), 885 GFP_KERNEL); 886 if (sdev->inquiry == NULL) 887 return SCSI_SCAN_NO_RESPONSE; 888 889 sdev->vendor = (char *) (sdev->inquiry + 8); 890 sdev->model = (char *) (sdev->inquiry + 16); 891 sdev->rev = (char *) (sdev->inquiry + 32); 892 893 if (strncmp(sdev->vendor, "ATA ", 8) == 0) { 894 /* 895 * sata emulation layer device. This is a hack to work around 896 * the SATL power management specifications which state that 897 * when the SATL detects the device has gone into standby 898 * mode, it shall respond with NOT READY. 899 */ 900 sdev->allow_restart = 1; 901 } 902 903 if (*bflags & BLIST_ISROM) { 904 sdev->type = TYPE_ROM; 905 sdev->removable = 1; 906 } else { 907 sdev->type = (inq_result[0] & 0x1f); 908 sdev->removable = (inq_result[1] & 0x80) >> 7; 909 910 /* 911 * some devices may respond with wrong type for 912 * well-known logical units. Force well-known type 913 * to enumerate them correctly. 914 */ 915 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) { 916 sdev_printk(KERN_WARNING, sdev, 917 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n", 918 __func__, sdev->type, (unsigned int)sdev->lun); 919 sdev->type = TYPE_WLUN; 920 } 921 922 } 923 924 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { 925 /* RBC and MMC devices can return SCSI-3 compliance and yet 926 * still not support REPORT LUNS, so make them act as 927 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is 928 * specifically set */ 929 if ((*bflags & BLIST_REPORTLUN2) == 0) 930 *bflags |= BLIST_NOREPORTLUN; 931 } 932 933 /* 934 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI 935 * spec says: The device server is capable of supporting the 936 * specified peripheral device type on this logical unit. However, 937 * the physical device is not currently connected to this logical 938 * unit. 939 * 940 * The above is vague, as it implies that we could treat 001 and 941 * 011 the same. Stay compatible with previous code, and create a 942 * scsi_device for a PQ of 1 943 * 944 * Don't set the device offline here; rather let the upper 945 * level drivers eval the PQ to decide whether they should 946 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. 947 */ 948 949 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; 950 sdev->lockable = sdev->removable; 951 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); 952 953 if (sdev->scsi_level >= SCSI_3 || 954 (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) 955 sdev->ppr = 1; 956 if (inq_result[7] & 0x60) 957 sdev->wdtr = 1; 958 if (inq_result[7] & 0x10) 959 sdev->sdtr = 1; 960 961 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " 962 "ANSI: %d%s\n", scsi_device_type(sdev->type), 963 sdev->vendor, sdev->model, sdev->rev, 964 sdev->inq_periph_qual, inq_result[2] & 0x07, 965 (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); 966 967 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && 968 !(*bflags & BLIST_NOTQ)) { 969 sdev->tagged_supported = 1; 970 sdev->simple_tags = 1; 971 } 972 973 /* 974 * Some devices (Texel CD ROM drives) have handshaking problems 975 * when used with the Seagate controllers. borken is initialized 976 * to 1, and then set it to 0 here. 977 */ 978 if ((*bflags & BLIST_BORKEN) == 0) 979 sdev->borken = 0; 980 981 if (*bflags & BLIST_NO_ULD_ATTACH) 982 sdev->no_uld_attach = 1; 983 984 /* 985 * Apparently some really broken devices (contrary to the SCSI 986 * standards) need to be selected without asserting ATN 987 */ 988 if (*bflags & BLIST_SELECT_NO_ATN) 989 sdev->select_no_atn = 1; 990 991 /* 992 * Maximum 512 sector transfer length 993 * broken RA4x00 Compaq Disk Array 994 */ 995 if (*bflags & BLIST_MAX_512) 996 blk_queue_max_hw_sectors(sdev->request_queue, 512); 997 /* 998 * Max 1024 sector transfer length for targets that report incorrect 999 * max/optimal lengths and relied on the old block layer safe default 1000 */ 1001 else if (*bflags & BLIST_MAX_1024) 1002 blk_queue_max_hw_sectors(sdev->request_queue, 1024); 1003 1004 /* 1005 * Some devices may not want to have a start command automatically 1006 * issued when a device is added. 1007 */ 1008 if (*bflags & BLIST_NOSTARTONADD) 1009 sdev->no_start_on_add = 1; 1010 1011 if (*bflags & BLIST_SINGLELUN) 1012 scsi_target(sdev)->single_lun = 1; 1013 1014 sdev->use_10_for_rw = 1; 1015 1016 /* some devices don't like REPORT SUPPORTED OPERATION CODES 1017 * and will simply timeout causing sd_mod init to take a very 1018 * very long time */ 1019 if (*bflags & BLIST_NO_RSOC) 1020 sdev->no_report_opcodes = 1; 1021 1022 /* set the device running here so that slave configure 1023 * may do I/O */ 1024 mutex_lock(&sdev->state_mutex); 1025 ret = scsi_device_set_state(sdev, SDEV_RUNNING); 1026 if (ret) 1027 ret = scsi_device_set_state(sdev, SDEV_BLOCK); 1028 mutex_unlock(&sdev->state_mutex); 1029 1030 if (ret) { 1031 sdev_printk(KERN_ERR, sdev, 1032 "in wrong state %s to complete scan\n", 1033 scsi_device_state_name(sdev->sdev_state)); 1034 return SCSI_SCAN_NO_RESPONSE; 1035 } 1036 1037 if (*bflags & BLIST_NOT_LOCKABLE) 1038 sdev->lockable = 0; 1039 1040 if (*bflags & BLIST_RETRY_HWERROR) 1041 sdev->retry_hwerror = 1; 1042 1043 if (*bflags & BLIST_NO_DIF) 1044 sdev->no_dif = 1; 1045 1046 if (*bflags & BLIST_UNMAP_LIMIT_WS) 1047 sdev->unmap_limit_for_ws = 1; 1048 1049 if (*bflags & BLIST_IGN_MEDIA_CHANGE) 1050 sdev->ignore_media_change = 1; 1051 1052 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; 1053 1054 if (*bflags & BLIST_TRY_VPD_PAGES) 1055 sdev->try_vpd_pages = 1; 1056 else if (*bflags & BLIST_SKIP_VPD_PAGES) 1057 sdev->skip_vpd_pages = 1; 1058 1059 transport_configure_device(&sdev->sdev_gendev); 1060 1061 if (sdev->host->hostt->slave_configure) { 1062 ret = sdev->host->hostt->slave_configure(sdev); 1063 if (ret) { 1064 /* 1065 * if LLDD reports slave not present, don't clutter 1066 * console with alloc failure messages 1067 */ 1068 if (ret != -ENXIO) { 1069 sdev_printk(KERN_ERR, sdev, 1070 "failed to configure device\n"); 1071 } 1072 return SCSI_SCAN_NO_RESPONSE; 1073 } 1074 1075 /* 1076 * The queue_depth is often changed in ->slave_configure. 1077 * Set up budget map again since memory consumption of 1078 * the map depends on actual queue depth. 1079 */ 1080 scsi_realloc_sdev_budget_map(sdev, sdev->queue_depth); 1081 } 1082 1083 if (sdev->scsi_level >= SCSI_3) 1084 scsi_attach_vpd(sdev); 1085 1086 sdev->max_queue_depth = sdev->queue_depth; 1087 WARN_ON_ONCE(sdev->max_queue_depth > sdev->budget_map.depth); 1088 sdev->sdev_bflags = *bflags; 1089 1090 /* 1091 * Ok, the device is now all set up, we can 1092 * register it and tell the rest of the kernel 1093 * about it. 1094 */ 1095 if (!async && scsi_sysfs_add_sdev(sdev) != 0) 1096 return SCSI_SCAN_NO_RESPONSE; 1097 1098 return SCSI_SCAN_LUN_PRESENT; 1099 } 1100 1101 #ifdef CONFIG_SCSI_LOGGING 1102 /** 1103 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace 1104 * @buf: Output buffer with at least end-first+1 bytes of space 1105 * @inq: Inquiry buffer (input) 1106 * @first: Offset of string into inq 1107 * @end: Index after last character in inq 1108 */ 1109 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, 1110 unsigned first, unsigned end) 1111 { 1112 unsigned term = 0, idx; 1113 1114 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { 1115 if (inq[idx+first] > ' ') { 1116 buf[idx] = inq[idx+first]; 1117 term = idx+1; 1118 } else { 1119 buf[idx] = ' '; 1120 } 1121 } 1122 buf[term] = 0; 1123 return buf; 1124 } 1125 #endif 1126 1127 /** 1128 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it 1129 * @starget: pointer to target device structure 1130 * @lun: LUN of target device 1131 * @bflagsp: store bflags here if not NULL 1132 * @sdevp: probe the LUN corresponding to this scsi_device 1133 * @rescan: if not equal to SCSI_SCAN_INITIAL skip some code only 1134 * needed on first scan 1135 * @hostdata: passed to scsi_alloc_sdev() 1136 * 1137 * Description: 1138 * Call scsi_probe_lun, if a LUN with an attached device is found, 1139 * allocate and set it up by calling scsi_add_lun. 1140 * 1141 * Return: 1142 * 1143 * - SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 1144 * - SCSI_SCAN_TARGET_PRESENT: target responded, but no device is 1145 * attached at the LUN 1146 * - SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 1147 **/ 1148 static int scsi_probe_and_add_lun(struct scsi_target *starget, 1149 u64 lun, blist_flags_t *bflagsp, 1150 struct scsi_device **sdevp, 1151 enum scsi_scan_mode rescan, 1152 void *hostdata) 1153 { 1154 struct scsi_device *sdev; 1155 unsigned char *result; 1156 blist_flags_t bflags; 1157 int res = SCSI_SCAN_NO_RESPONSE, result_len = 256; 1158 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1159 1160 /* 1161 * The rescan flag is used as an optimization, the first scan of a 1162 * host adapter calls into here with rescan == 0. 1163 */ 1164 sdev = scsi_device_lookup_by_target(starget, lun); 1165 if (sdev) { 1166 if (rescan != SCSI_SCAN_INITIAL || !scsi_device_created(sdev)) { 1167 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1168 "scsi scan: device exists on %s\n", 1169 dev_name(&sdev->sdev_gendev))); 1170 if (sdevp) 1171 *sdevp = sdev; 1172 else 1173 scsi_device_put(sdev); 1174 1175 if (bflagsp) 1176 *bflagsp = scsi_get_device_flags(sdev, 1177 sdev->vendor, 1178 sdev->model); 1179 return SCSI_SCAN_LUN_PRESENT; 1180 } 1181 scsi_device_put(sdev); 1182 } else 1183 sdev = scsi_alloc_sdev(starget, lun, hostdata); 1184 if (!sdev) 1185 goto out; 1186 1187 result = kmalloc(result_len, GFP_KERNEL); 1188 if (!result) 1189 goto out_free_sdev; 1190 1191 if (scsi_probe_lun(sdev, result, result_len, &bflags)) 1192 goto out_free_result; 1193 1194 if (bflagsp) 1195 *bflagsp = bflags; 1196 /* 1197 * result contains valid SCSI INQUIRY data. 1198 */ 1199 if ((result[0] >> 5) == 3) { 1200 /* 1201 * For a Peripheral qualifier 3 (011b), the SCSI 1202 * spec says: The device server is not capable of 1203 * supporting a physical device on this logical 1204 * unit. 1205 * 1206 * For disks, this implies that there is no 1207 * logical disk configured at sdev->lun, but there 1208 * is a target id responding. 1209 */ 1210 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" 1211 " peripheral qualifier of 3, device not" 1212 " added\n")) 1213 if (lun == 0) { 1214 SCSI_LOG_SCAN_BUS(1, { 1215 unsigned char vend[9]; 1216 unsigned char mod[17]; 1217 1218 sdev_printk(KERN_INFO, sdev, 1219 "scsi scan: consider passing scsi_mod." 1220 "dev_flags=%s:%s:0x240 or 0x1000240\n", 1221 scsi_inq_str(vend, result, 8, 16), 1222 scsi_inq_str(mod, result, 16, 32)); 1223 }); 1224 1225 } 1226 1227 res = SCSI_SCAN_TARGET_PRESENT; 1228 goto out_free_result; 1229 } 1230 1231 /* 1232 * Some targets may set slight variations of PQ and PDT to signal 1233 * that no LUN is present, so don't add sdev in these cases. 1234 * Two specific examples are: 1235 * 1) NetApp targets: return PQ=1, PDT=0x1f 1236 * 2) IBM/2145 targets: return PQ=1, PDT=0 1237 * 3) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" 1238 * in the UFI 1.0 spec (we cannot rely on reserved bits). 1239 * 1240 * References: 1241 * 1) SCSI SPC-3, pp. 145-146 1242 * PQ=1: "A peripheral device having the specified peripheral 1243 * device type is not connected to this logical unit. However, the 1244 * device server is capable of supporting the specified peripheral 1245 * device type on this logical unit." 1246 * PDT=0x1f: "Unknown or no device type" 1247 * 2) USB UFI 1.0, p. 20 1248 * PDT=00h Direct-access device (floppy) 1249 * PDT=1Fh none (no FDD connected to the requested logical unit) 1250 */ 1251 if (((result[0] >> 5) == 1 || 1252 (starget->pdt_1f_for_no_lun && (result[0] & 0x1f) == 0x1f)) && 1253 !scsi_is_wlun(lun)) { 1254 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1255 "scsi scan: peripheral device type" 1256 " of 31, no device added\n")); 1257 res = SCSI_SCAN_TARGET_PRESENT; 1258 goto out_free_result; 1259 } 1260 1261 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); 1262 if (res == SCSI_SCAN_LUN_PRESENT) { 1263 if (bflags & BLIST_KEY) { 1264 sdev->lockable = 0; 1265 scsi_unlock_floptical(sdev, result); 1266 } 1267 } 1268 1269 out_free_result: 1270 kfree(result); 1271 out_free_sdev: 1272 if (res == SCSI_SCAN_LUN_PRESENT) { 1273 if (sdevp) { 1274 if (scsi_device_get(sdev) == 0) { 1275 *sdevp = sdev; 1276 } else { 1277 __scsi_remove_device(sdev); 1278 res = SCSI_SCAN_NO_RESPONSE; 1279 } 1280 } 1281 } else 1282 __scsi_remove_device(sdev); 1283 out: 1284 return res; 1285 } 1286 1287 /** 1288 * scsi_sequential_lun_scan - sequentially scan a SCSI target 1289 * @starget: pointer to target structure to scan 1290 * @bflags: black/white list flag for LUN 0 1291 * @scsi_level: Which version of the standard does this device adhere to 1292 * @rescan: passed to scsi_probe_add_lun() 1293 * 1294 * Description: 1295 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been 1296 * scanned) to some maximum lun until a LUN is found with no device 1297 * attached. Use the bflags to figure out any oddities. 1298 * 1299 * Modifies sdevscan->lun. 1300 **/ 1301 static void scsi_sequential_lun_scan(struct scsi_target *starget, 1302 blist_flags_t bflags, int scsi_level, 1303 enum scsi_scan_mode rescan) 1304 { 1305 uint max_dev_lun; 1306 u64 sparse_lun, lun; 1307 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1308 1309 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget, 1310 "scsi scan: Sequential scan\n")); 1311 1312 max_dev_lun = min(max_scsi_luns, shost->max_lun); 1313 /* 1314 * If this device is known to support sparse multiple units, 1315 * override the other settings, and scan all of them. Normally, 1316 * SCSI-3 devices should be scanned via the REPORT LUNS. 1317 */ 1318 if (bflags & BLIST_SPARSELUN) { 1319 max_dev_lun = shost->max_lun; 1320 sparse_lun = 1; 1321 } else 1322 sparse_lun = 0; 1323 1324 /* 1325 * If less than SCSI_1_CCS, and no special lun scanning, stop 1326 * scanning; this matches 2.4 behaviour, but could just be a bug 1327 * (to continue scanning a SCSI_1_CCS device). 1328 * 1329 * This test is broken. We might not have any device on lun0 for 1330 * a sparselun device, and if that's the case then how would we 1331 * know the real scsi_level, eh? It might make sense to just not 1332 * scan any SCSI_1 device for non-0 luns, but that check would best 1333 * go into scsi_alloc_sdev() and just have it return null when asked 1334 * to alloc an sdev for lun > 0 on an already found SCSI_1 device. 1335 * 1336 if ((sdevscan->scsi_level < SCSI_1_CCS) && 1337 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) 1338 == 0)) 1339 return; 1340 */ 1341 /* 1342 * If this device is known to support multiple units, override 1343 * the other settings, and scan all of them. 1344 */ 1345 if (bflags & BLIST_FORCELUN) 1346 max_dev_lun = shost->max_lun; 1347 /* 1348 * REGAL CDC-4X: avoid hang after LUN 4 1349 */ 1350 if (bflags & BLIST_MAX5LUN) 1351 max_dev_lun = min(5U, max_dev_lun); 1352 /* 1353 * Do not scan SCSI-2 or lower device past LUN 7, unless 1354 * BLIST_LARGELUN. 1355 */ 1356 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) 1357 max_dev_lun = min(8U, max_dev_lun); 1358 else 1359 max_dev_lun = min(256U, max_dev_lun); 1360 1361 /* 1362 * We have already scanned LUN 0, so start at LUN 1. Keep scanning 1363 * until we reach the max, or no LUN is found and we are not 1364 * sparse_lun. 1365 */ 1366 for (lun = 1; lun < max_dev_lun; ++lun) 1367 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, 1368 NULL) != SCSI_SCAN_LUN_PRESENT) && 1369 !sparse_lun) 1370 return; 1371 } 1372 1373 /** 1374 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results 1375 * @starget: which target 1376 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN 1377 * @rescan: nonzero if we can skip code only needed on first scan 1378 * 1379 * Description: 1380 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. 1381 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. 1382 * 1383 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 1384 * LUNs even if it's older than SCSI-3. 1385 * If BLIST_NOREPORTLUN is set, return 1 always. 1386 * If BLIST_NOLUN is set, return 0 always. 1387 * If starget->no_report_luns is set, return 1 always. 1388 * 1389 * Return: 1390 * 0: scan completed (or no memory, so further scanning is futile) 1391 * 1: could not scan with REPORT LUN 1392 **/ 1393 static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflags, 1394 enum scsi_scan_mode rescan) 1395 { 1396 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 1397 unsigned int length; 1398 u64 lun; 1399 unsigned int num_luns; 1400 unsigned int retries; 1401 int result; 1402 struct scsi_lun *lunp, *lun_data; 1403 struct scsi_sense_hdr sshdr; 1404 struct scsi_device *sdev; 1405 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 1406 int ret = 0; 1407 1408 /* 1409 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. 1410 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does 1411 * support more than 8 LUNs. 1412 * Don't attempt if the target doesn't support REPORT LUNS. 1413 */ 1414 if (bflags & BLIST_NOREPORTLUN) 1415 return 1; 1416 if (starget->scsi_level < SCSI_2 && 1417 starget->scsi_level != SCSI_UNKNOWN) 1418 return 1; 1419 if (starget->scsi_level < SCSI_3 && 1420 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) 1421 return 1; 1422 if (bflags & BLIST_NOLUN) 1423 return 0; 1424 if (starget->no_report_luns) 1425 return 1; 1426 1427 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { 1428 sdev = scsi_alloc_sdev(starget, 0, NULL); 1429 if (!sdev) 1430 return 0; 1431 if (scsi_device_get(sdev)) { 1432 __scsi_remove_device(sdev); 1433 return 0; 1434 } 1435 } 1436 1437 /* 1438 * Allocate enough to hold the header (the same size as one scsi_lun) 1439 * plus the number of luns we are requesting. 511 was the default 1440 * value of the now removed max_report_luns parameter. 1441 */ 1442 length = (511 + 1) * sizeof(struct scsi_lun); 1443 retry: 1444 lun_data = kmalloc(length, GFP_KERNEL); 1445 if (!lun_data) { 1446 printk(ALLOC_FAILURE_MSG, __func__); 1447 goto out; 1448 } 1449 1450 scsi_cmd[0] = REPORT_LUNS; 1451 1452 /* 1453 * bytes 1 - 5: reserved, set to zero. 1454 */ 1455 memset(&scsi_cmd[1], 0, 5); 1456 1457 /* 1458 * bytes 6 - 9: length of the command. 1459 */ 1460 put_unaligned_be32(length, &scsi_cmd[6]); 1461 1462 scsi_cmd[10] = 0; /* reserved */ 1463 scsi_cmd[11] = 0; /* control */ 1464 1465 /* 1466 * We can get a UNIT ATTENTION, for example a power on/reset, so 1467 * retry a few times (like sd.c does for TEST UNIT READY). 1468 * Experience shows some combinations of adapter/devices get at 1469 * least two power on/resets. 1470 * 1471 * Illegal requests (for devices that do not support REPORT LUNS) 1472 * should come through as a check condition, and will not generate 1473 * a retry. 1474 */ 1475 for (retries = 0; retries < 3; retries++) { 1476 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1477 "scsi scan: Sending REPORT LUNS to (try %d)\n", 1478 retries)); 1479 1480 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 1481 lun_data, length, &sshdr, 1482 SCSI_REPORT_LUNS_TIMEOUT, 3, NULL); 1483 1484 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1485 "scsi scan: REPORT LUNS" 1486 " %s (try %d) result 0x%x\n", 1487 result ? "failed" : "successful", 1488 retries, result)); 1489 if (result == 0) 1490 break; 1491 else if (scsi_sense_valid(&sshdr)) { 1492 if (sshdr.sense_key != UNIT_ATTENTION) 1493 break; 1494 } 1495 } 1496 1497 if (result) { 1498 /* 1499 * The device probably does not support a REPORT LUN command 1500 */ 1501 ret = 1; 1502 goto out_err; 1503 } 1504 1505 /* 1506 * Get the length from the first four bytes of lun_data. 1507 */ 1508 if (get_unaligned_be32(lun_data->scsi_lun) + 1509 sizeof(struct scsi_lun) > length) { 1510 length = get_unaligned_be32(lun_data->scsi_lun) + 1511 sizeof(struct scsi_lun); 1512 kfree(lun_data); 1513 goto retry; 1514 } 1515 length = get_unaligned_be32(lun_data->scsi_lun); 1516 1517 num_luns = (length / sizeof(struct scsi_lun)); 1518 1519 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1520 "scsi scan: REPORT LUN scan\n")); 1521 1522 /* 1523 * Scan the luns in lun_data. The entry at offset 0 is really 1524 * the header, so start at 1 and go up to and including num_luns. 1525 */ 1526 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { 1527 lun = scsilun_to_int(lunp); 1528 1529 if (lun > sdev->host->max_lun) { 1530 sdev_printk(KERN_WARNING, sdev, 1531 "lun%llu has a LUN larger than" 1532 " allowed by the host adapter\n", lun); 1533 } else { 1534 int res; 1535 1536 res = scsi_probe_and_add_lun(starget, 1537 lun, NULL, NULL, rescan, NULL); 1538 if (res == SCSI_SCAN_NO_RESPONSE) { 1539 /* 1540 * Got some results, but now none, abort. 1541 */ 1542 sdev_printk(KERN_ERR, sdev, 1543 "Unexpected response" 1544 " from lun %llu while scanning, scan" 1545 " aborted\n", (unsigned long long)lun); 1546 break; 1547 } 1548 } 1549 } 1550 1551 out_err: 1552 kfree(lun_data); 1553 out: 1554 if (scsi_device_created(sdev)) 1555 /* 1556 * the sdev we used didn't appear in the report luns scan 1557 */ 1558 __scsi_remove_device(sdev); 1559 scsi_device_put(sdev); 1560 return ret; 1561 } 1562 1563 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, 1564 uint id, u64 lun, void *hostdata) 1565 { 1566 struct scsi_device *sdev = ERR_PTR(-ENODEV); 1567 struct device *parent = &shost->shost_gendev; 1568 struct scsi_target *starget; 1569 1570 if (strncmp(scsi_scan_type, "none", 4) == 0) 1571 return ERR_PTR(-ENODEV); 1572 1573 starget = scsi_alloc_target(parent, channel, id); 1574 if (!starget) 1575 return ERR_PTR(-ENOMEM); 1576 scsi_autopm_get_target(starget); 1577 1578 mutex_lock(&shost->scan_mutex); 1579 if (!shost->async_scan) 1580 scsi_complete_async_scans(); 1581 1582 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1583 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); 1584 scsi_autopm_put_host(shost); 1585 } 1586 mutex_unlock(&shost->scan_mutex); 1587 scsi_autopm_put_target(starget); 1588 /* 1589 * paired with scsi_alloc_target(). Target will be destroyed unless 1590 * scsi_probe_and_add_lun made an underlying device visible 1591 */ 1592 scsi_target_reap(starget); 1593 put_device(&starget->dev); 1594 1595 return sdev; 1596 } 1597 EXPORT_SYMBOL(__scsi_add_device); 1598 1599 int scsi_add_device(struct Scsi_Host *host, uint channel, 1600 uint target, u64 lun) 1601 { 1602 struct scsi_device *sdev = 1603 __scsi_add_device(host, channel, target, lun, NULL); 1604 if (IS_ERR(sdev)) 1605 return PTR_ERR(sdev); 1606 1607 scsi_device_put(sdev); 1608 return 0; 1609 } 1610 EXPORT_SYMBOL(scsi_add_device); 1611 1612 void scsi_rescan_device(struct device *dev) 1613 { 1614 struct scsi_device *sdev = to_scsi_device(dev); 1615 1616 device_lock(dev); 1617 1618 scsi_attach_vpd(sdev); 1619 1620 if (sdev->handler && sdev->handler->rescan) 1621 sdev->handler->rescan(sdev); 1622 1623 if (dev->driver && try_module_get(dev->driver->owner)) { 1624 struct scsi_driver *drv = to_scsi_driver(dev->driver); 1625 1626 if (drv->rescan) 1627 drv->rescan(dev); 1628 module_put(dev->driver->owner); 1629 } 1630 device_unlock(dev); 1631 } 1632 EXPORT_SYMBOL(scsi_rescan_device); 1633 1634 static void __scsi_scan_target(struct device *parent, unsigned int channel, 1635 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1636 { 1637 struct Scsi_Host *shost = dev_to_shost(parent); 1638 blist_flags_t bflags = 0; 1639 int res; 1640 struct scsi_target *starget; 1641 1642 if (shost->this_id == id) 1643 /* 1644 * Don't scan the host adapter 1645 */ 1646 return; 1647 1648 starget = scsi_alloc_target(parent, channel, id); 1649 if (!starget) 1650 return; 1651 scsi_autopm_get_target(starget); 1652 1653 if (lun != SCAN_WILD_CARD) { 1654 /* 1655 * Scan for a specific host/chan/id/lun. 1656 */ 1657 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); 1658 goto out_reap; 1659 } 1660 1661 /* 1662 * Scan LUN 0, if there is some response, scan further. Ideally, we 1663 * would not configure LUN 0 until all LUNs are scanned. 1664 */ 1665 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); 1666 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { 1667 if (scsi_report_lun_scan(starget, bflags, rescan) != 0) 1668 /* 1669 * The REPORT LUN did not scan the target, 1670 * do a sequential scan. 1671 */ 1672 scsi_sequential_lun_scan(starget, bflags, 1673 starget->scsi_level, rescan); 1674 } 1675 1676 out_reap: 1677 scsi_autopm_put_target(starget); 1678 /* 1679 * paired with scsi_alloc_target(): determine if the target has 1680 * any children at all and if not, nuke it 1681 */ 1682 scsi_target_reap(starget); 1683 1684 put_device(&starget->dev); 1685 } 1686 1687 /** 1688 * scsi_scan_target - scan a target id, possibly including all LUNs on the target. 1689 * @parent: host to scan 1690 * @channel: channel to scan 1691 * @id: target id to scan 1692 * @lun: Specific LUN to scan or SCAN_WILD_CARD 1693 * @rescan: passed to LUN scanning routines; SCSI_SCAN_INITIAL for 1694 * no rescan, SCSI_SCAN_RESCAN to rescan existing LUNs, 1695 * and SCSI_SCAN_MANUAL to force scanning even if 1696 * 'scan=manual' is set. 1697 * 1698 * Description: 1699 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, 1700 * and possibly all LUNs on the target id. 1701 * 1702 * First try a REPORT LUN scan, if that does not scan the target, do a 1703 * sequential scan of LUNs on the target id. 1704 **/ 1705 void scsi_scan_target(struct device *parent, unsigned int channel, 1706 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1707 { 1708 struct Scsi_Host *shost = dev_to_shost(parent); 1709 1710 if (strncmp(scsi_scan_type, "none", 4) == 0) 1711 return; 1712 1713 if (rescan != SCSI_SCAN_MANUAL && 1714 strncmp(scsi_scan_type, "manual", 6) == 0) 1715 return; 1716 1717 mutex_lock(&shost->scan_mutex); 1718 if (!shost->async_scan) 1719 scsi_complete_async_scans(); 1720 1721 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1722 __scsi_scan_target(parent, channel, id, lun, rescan); 1723 scsi_autopm_put_host(shost); 1724 } 1725 mutex_unlock(&shost->scan_mutex); 1726 } 1727 EXPORT_SYMBOL(scsi_scan_target); 1728 1729 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, 1730 unsigned int id, u64 lun, 1731 enum scsi_scan_mode rescan) 1732 { 1733 uint order_id; 1734 1735 if (id == SCAN_WILD_CARD) 1736 for (id = 0; id < shost->max_id; ++id) { 1737 /* 1738 * XXX adapter drivers when possible (FCP, iSCSI) 1739 * could modify max_id to match the current max, 1740 * not the absolute max. 1741 * 1742 * XXX add a shost id iterator, so for example, 1743 * the FC ID can be the same as a target id 1744 * without a huge overhead of sparse id's. 1745 */ 1746 if (shost->reverse_ordering) 1747 /* 1748 * Scan from high to low id. 1749 */ 1750 order_id = shost->max_id - id - 1; 1751 else 1752 order_id = id; 1753 __scsi_scan_target(&shost->shost_gendev, channel, 1754 order_id, lun, rescan); 1755 } 1756 else 1757 __scsi_scan_target(&shost->shost_gendev, channel, 1758 id, lun, rescan); 1759 } 1760 1761 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, 1762 unsigned int id, u64 lun, 1763 enum scsi_scan_mode rescan) 1764 { 1765 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, 1766 "%s: <%u:%u:%llu>\n", 1767 __func__, channel, id, lun)); 1768 1769 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || 1770 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || 1771 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun))) 1772 return -EINVAL; 1773 1774 mutex_lock(&shost->scan_mutex); 1775 if (!shost->async_scan) 1776 scsi_complete_async_scans(); 1777 1778 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1779 if (channel == SCAN_WILD_CARD) 1780 for (channel = 0; channel <= shost->max_channel; 1781 channel++) 1782 scsi_scan_channel(shost, channel, id, lun, 1783 rescan); 1784 else 1785 scsi_scan_channel(shost, channel, id, lun, rescan); 1786 scsi_autopm_put_host(shost); 1787 } 1788 mutex_unlock(&shost->scan_mutex); 1789 1790 return 0; 1791 } 1792 1793 static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 1794 { 1795 struct scsi_device *sdev; 1796 shost_for_each_device(sdev, shost) { 1797 /* target removed before the device could be added */ 1798 if (sdev->sdev_state == SDEV_DEL) 1799 continue; 1800 /* If device is already visible, skip adding it to sysfs */ 1801 if (sdev->is_visible) 1802 continue; 1803 if (!scsi_host_scan_allowed(shost) || 1804 scsi_sysfs_add_sdev(sdev) != 0) 1805 __scsi_remove_device(sdev); 1806 } 1807 } 1808 1809 /** 1810 * scsi_prep_async_scan - prepare for an async scan 1811 * @shost: the host which will be scanned 1812 * Returns: a cookie to be passed to scsi_finish_async_scan() 1813 * 1814 * Tells the midlayer this host is going to do an asynchronous scan. 1815 * It reserves the host's position in the scanning list and ensures 1816 * that other asynchronous scans started after this one won't affect the 1817 * ordering of the discovered devices. 1818 */ 1819 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 1820 { 1821 struct async_scan_data *data = NULL; 1822 unsigned long flags; 1823 1824 if (strncmp(scsi_scan_type, "sync", 4) == 0) 1825 return NULL; 1826 1827 mutex_lock(&shost->scan_mutex); 1828 if (shost->async_scan) { 1829 shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__); 1830 goto err; 1831 } 1832 1833 data = kmalloc(sizeof(*data), GFP_KERNEL); 1834 if (!data) 1835 goto err; 1836 data->shost = scsi_host_get(shost); 1837 if (!data->shost) 1838 goto err; 1839 init_completion(&data->prev_finished); 1840 1841 spin_lock_irqsave(shost->host_lock, flags); 1842 shost->async_scan = 1; 1843 spin_unlock_irqrestore(shost->host_lock, flags); 1844 mutex_unlock(&shost->scan_mutex); 1845 1846 spin_lock(&async_scan_lock); 1847 if (list_empty(&scanning_hosts)) 1848 complete(&data->prev_finished); 1849 list_add_tail(&data->list, &scanning_hosts); 1850 spin_unlock(&async_scan_lock); 1851 1852 return data; 1853 1854 err: 1855 mutex_unlock(&shost->scan_mutex); 1856 kfree(data); 1857 return NULL; 1858 } 1859 1860 /** 1861 * scsi_finish_async_scan - asynchronous scan has finished 1862 * @data: cookie returned from earlier call to scsi_prep_async_scan() 1863 * 1864 * All the devices currently attached to this host have been found. 1865 * This function announces all the devices it has found to the rest 1866 * of the system. 1867 */ 1868 static void scsi_finish_async_scan(struct async_scan_data *data) 1869 { 1870 struct Scsi_Host *shost; 1871 unsigned long flags; 1872 1873 if (!data) 1874 return; 1875 1876 shost = data->shost; 1877 1878 mutex_lock(&shost->scan_mutex); 1879 1880 if (!shost->async_scan) { 1881 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1882 dump_stack(); 1883 mutex_unlock(&shost->scan_mutex); 1884 return; 1885 } 1886 1887 wait_for_completion(&data->prev_finished); 1888 1889 scsi_sysfs_add_devices(shost); 1890 1891 spin_lock_irqsave(shost->host_lock, flags); 1892 shost->async_scan = 0; 1893 spin_unlock_irqrestore(shost->host_lock, flags); 1894 1895 mutex_unlock(&shost->scan_mutex); 1896 1897 spin_lock(&async_scan_lock); 1898 list_del(&data->list); 1899 if (!list_empty(&scanning_hosts)) { 1900 struct async_scan_data *next = list_entry(scanning_hosts.next, 1901 struct async_scan_data, list); 1902 complete(&next->prev_finished); 1903 } 1904 spin_unlock(&async_scan_lock); 1905 1906 scsi_autopm_put_host(shost); 1907 scsi_host_put(shost); 1908 kfree(data); 1909 } 1910 1911 static void do_scsi_scan_host(struct Scsi_Host *shost) 1912 { 1913 if (shost->hostt->scan_finished) { 1914 unsigned long start = jiffies; 1915 if (shost->hostt->scan_start) 1916 shost->hostt->scan_start(shost); 1917 1918 while (!shost->hostt->scan_finished(shost, jiffies - start)) 1919 msleep(10); 1920 } else { 1921 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, 1922 SCAN_WILD_CARD, 0); 1923 } 1924 } 1925 1926 static void do_scan_async(void *_data, async_cookie_t c) 1927 { 1928 struct async_scan_data *data = _data; 1929 struct Scsi_Host *shost = data->shost; 1930 1931 do_scsi_scan_host(shost); 1932 scsi_finish_async_scan(data); 1933 } 1934 1935 /** 1936 * scsi_scan_host - scan the given adapter 1937 * @shost: adapter to scan 1938 **/ 1939 void scsi_scan_host(struct Scsi_Host *shost) 1940 { 1941 struct async_scan_data *data; 1942 1943 if (strncmp(scsi_scan_type, "none", 4) == 0 || 1944 strncmp(scsi_scan_type, "manual", 6) == 0) 1945 return; 1946 if (scsi_autopm_get_host(shost) < 0) 1947 return; 1948 1949 data = scsi_prep_async_scan(shost); 1950 if (!data) { 1951 do_scsi_scan_host(shost); 1952 scsi_autopm_put_host(shost); 1953 return; 1954 } 1955 1956 /* register with the async subsystem so wait_for_device_probe() 1957 * will flush this work 1958 */ 1959 async_schedule(do_scan_async, data); 1960 1961 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */ 1962 } 1963 EXPORT_SYMBOL(scsi_scan_host); 1964 1965 void scsi_forget_host(struct Scsi_Host *shost) 1966 { 1967 struct scsi_device *sdev; 1968 unsigned long flags; 1969 1970 restart: 1971 spin_lock_irqsave(shost->host_lock, flags); 1972 list_for_each_entry(sdev, &shost->__devices, siblings) { 1973 if (sdev->sdev_state == SDEV_DEL) 1974 continue; 1975 spin_unlock_irqrestore(shost->host_lock, flags); 1976 __scsi_remove_device(sdev); 1977 goto restart; 1978 } 1979 spin_unlock_irqrestore(shost->host_lock, flags); 1980 } 1981 1982