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 84static const char *scsi_null_device_strs = "nullnullnullnull"; 85 86#define MAX_SCSI_LUNS 512 87 88static u64 max_scsi_luns = MAX_SCSI_LUNS; 89 90module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR); 91MODULE_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 100static char scsi_scan_type[7] = SCSI_SCAN_TYPE_DEFAULT; 101 102module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), 103 S_IRUGO|S_IWUSR); 104MODULE_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 108static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18; 109 110module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); 111MODULE_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 */ 116static DEFINE_SPINLOCK(async_scan_lock); 117static LIST_HEAD(scanning_hosts); 118 119struct 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 */ 128void 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 */ 149int 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 **/ 201static 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_cmd(sdev, scsi_cmd, REQ_OP_DRV_IN, result, 0x2a, 214 SCSI_TIMEOUT, 3, NULL); 215} 216 217static 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 **/ 278static 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_alloc_queue(&sdev->host->tag_set, NULL, NULL); 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); 347 348 depth = sdev->host->cmd_per_lun ?: 1; 349 350 /* 351 * Use .can_queue as budget map's depth because we have to 352 * support adjusting queue depth from sysfs. Meantime use 353 * default device queue depth to figure out sbitmap shift 354 * since we use this queue depth most of times. 355 */ 356 if (scsi_realloc_sdev_budget_map(sdev, depth)) { 357 put_device(&starget->dev); 358 kfree(sdev); 359 goto out; 360 } 361 362 scsi_change_queue_depth(sdev, depth); 363 364 scsi_sysfs_device_initialize(sdev); 365 366 if (shost->hostt->slave_alloc) { 367 ret = shost->hostt->slave_alloc(sdev); 368 if (ret) { 369 /* 370 * if LLDD reports slave not present, don't clutter 371 * console with alloc failure messages 372 */ 373 if (ret == -ENXIO) 374 display_failure_msg = 0; 375 goto out_device_destroy; 376 } 377 } 378 379 return sdev; 380 381out_device_destroy: 382 __scsi_remove_device(sdev); 383out: 384 if (display_failure_msg) 385 printk(ALLOC_FAILURE_MSG, __func__); 386 return NULL; 387} 388 389static void scsi_target_destroy(struct scsi_target *starget) 390{ 391 struct device *dev = &starget->dev; 392 struct Scsi_Host *shost = dev_to_shost(dev->parent); 393 unsigned long flags; 394 395 BUG_ON(starget->state == STARGET_DEL); 396 starget->state = STARGET_DEL; 397 transport_destroy_device(dev); 398 spin_lock_irqsave(shost->host_lock, flags); 399 if (shost->hostt->target_destroy) 400 shost->hostt->target_destroy(starget); 401 list_del_init(&starget->siblings); 402 spin_unlock_irqrestore(shost->host_lock, flags); 403 put_device(dev); 404} 405 406static void scsi_target_dev_release(struct device *dev) 407{ 408 struct device *parent = dev->parent; 409 struct scsi_target *starget = to_scsi_target(dev); 410 411 kfree(starget); 412 put_device(parent); 413} 414 415static const struct device_type scsi_target_type = { 416 .name = "scsi_target", 417 .release = scsi_target_dev_release, 418}; 419 420int scsi_is_target_device(const struct device *dev) 421{ 422 return dev->type == &scsi_target_type; 423} 424EXPORT_SYMBOL(scsi_is_target_device); 425 426static struct scsi_target *__scsi_find_target(struct device *parent, 427 int channel, uint id) 428{ 429 struct scsi_target *starget, *found_starget = NULL; 430 struct Scsi_Host *shost = dev_to_shost(parent); 431 /* 432 * Search for an existing target for this sdev. 433 */ 434 list_for_each_entry(starget, &shost->__targets, siblings) { 435 if (starget->id == id && 436 starget->channel == channel) { 437 found_starget = starget; 438 break; 439 } 440 } 441 if (found_starget) 442 get_device(&found_starget->dev); 443 444 return found_starget; 445} 446 447/** 448 * scsi_target_reap_ref_release - remove target from visibility 449 * @kref: the reap_ref in the target being released 450 * 451 * Called on last put of reap_ref, which is the indication that no device 452 * under this target is visible anymore, so render the target invisible in 453 * sysfs. Note: we have to be in user context here because the target reaps 454 * should be done in places where the scsi device visibility is being removed. 455 */ 456static void scsi_target_reap_ref_release(struct kref *kref) 457{ 458 struct scsi_target *starget 459 = container_of(kref, struct scsi_target, reap_ref); 460 461 /* 462 * if we get here and the target is still in a CREATED state that 463 * means it was allocated but never made visible (because a scan 464 * turned up no LUNs), so don't call device_del() on it. 465 */ 466 if ((starget->state != STARGET_CREATED) && 467 (starget->state != STARGET_CREATED_REMOVE)) { 468 transport_remove_device(&starget->dev); 469 device_del(&starget->dev); 470 } 471 scsi_target_destroy(starget); 472} 473 474static void scsi_target_reap_ref_put(struct scsi_target *starget) 475{ 476 kref_put(&starget->reap_ref, scsi_target_reap_ref_release); 477} 478 479/** 480 * scsi_alloc_target - allocate a new or find an existing target 481 * @parent: parent of the target (need not be a scsi host) 482 * @channel: target channel number (zero if no channels) 483 * @id: target id number 484 * 485 * Return an existing target if one exists, provided it hasn't already 486 * gone into STARGET_DEL state, otherwise allocate a new target. 487 * 488 * The target is returned with an incremented reference, so the caller 489 * is responsible for both reaping and doing a last put 490 */ 491static struct scsi_target *scsi_alloc_target(struct device *parent, 492 int channel, uint id) 493{ 494 struct Scsi_Host *shost = dev_to_shost(parent); 495 struct device *dev = NULL; 496 unsigned long flags; 497 const int size = sizeof(struct scsi_target) 498 + shost->transportt->target_size; 499 struct scsi_target *starget; 500 struct scsi_target *found_target; 501 int error, ref_got; 502 503 starget = kzalloc(size, GFP_KERNEL); 504 if (!starget) { 505 printk(KERN_ERR "%s: allocation failure\n", __func__); 506 return NULL; 507 } 508 dev = &starget->dev; 509 device_initialize(dev); 510 kref_init(&starget->reap_ref); 511 dev->parent = get_device(parent); 512 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); 513 dev->bus = &scsi_bus_type; 514 dev->type = &scsi_target_type; 515 scsi_enable_async_suspend(dev); 516 starget->id = id; 517 starget->channel = channel; 518 starget->can_queue = 0; 519 INIT_LIST_HEAD(&starget->siblings); 520 INIT_LIST_HEAD(&starget->devices); 521 starget->state = STARGET_CREATED; 522 starget->scsi_level = SCSI_2; 523 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; 524 retry: 525 spin_lock_irqsave(shost->host_lock, flags); 526 527 found_target = __scsi_find_target(parent, channel, id); 528 if (found_target) 529 goto found; 530 531 list_add_tail(&starget->siblings, &shost->__targets); 532 spin_unlock_irqrestore(shost->host_lock, flags); 533 /* allocate and add */ 534 transport_setup_device(dev); 535 if (shost->hostt->target_alloc) { 536 error = shost->hostt->target_alloc(starget); 537 538 if(error) { 539 if (error != -ENXIO) 540 dev_err(dev, "target allocation failed, error %d\n", error); 541 /* don't want scsi_target_reap to do the final 542 * put because it will be under the host lock */ 543 scsi_target_destroy(starget); 544 return NULL; 545 } 546 } 547 get_device(dev); 548 549 return starget; 550 551 found: 552 /* 553 * release routine already fired if kref is zero, so if we can still 554 * take the reference, the target must be alive. If we can't, it must 555 * be dying and we need to wait for a new target 556 */ 557 ref_got = kref_get_unless_zero(&found_target->reap_ref); 558 559 spin_unlock_irqrestore(shost->host_lock, flags); 560 if (ref_got) { 561 put_device(dev); 562 return found_target; 563 } 564 /* 565 * Unfortunately, we found a dying target; need to wait until it's 566 * dead before we can get a new one. There is an anomaly here. We 567 * *should* call scsi_target_reap() to balance the kref_get() of the 568 * reap_ref above. However, since the target being released, it's 569 * already invisible and the reap_ref is irrelevant. If we call 570 * scsi_target_reap() we might spuriously do another device_del() on 571 * an already invisible target. 572 */ 573 put_device(&found_target->dev); 574 /* 575 * length of time is irrelevant here, we just want to yield the CPU 576 * for a tick to avoid busy waiting for the target to die. 577 */ 578 msleep(1); 579 goto retry; 580} 581 582/** 583 * scsi_target_reap - check to see if target is in use and destroy if not 584 * @starget: target to be checked 585 * 586 * This is used after removing a LUN or doing a last put of the target 587 * it checks atomically that nothing is using the target and removes 588 * it if so. 589 */ 590void scsi_target_reap(struct scsi_target *starget) 591{ 592 /* 593 * serious problem if this triggers: STARGET_DEL is only set in the if 594 * the reap_ref drops to zero, so we're trying to do another final put 595 * on an already released kref 596 */ 597 BUG_ON(starget->state == STARGET_DEL); 598 scsi_target_reap_ref_put(starget); 599} 600 601/** 602 * scsi_sanitize_inquiry_string - remove non-graphical chars from an 603 * INQUIRY result string 604 * @s: INQUIRY result string to sanitize 605 * @len: length of the string 606 * 607 * Description: 608 * The SCSI spec says that INQUIRY vendor, product, and revision 609 * strings must consist entirely of graphic ASCII characters, 610 * padded on the right with spaces. Since not all devices obey 611 * this rule, we will replace non-graphic or non-ASCII characters 612 * with spaces. Exception: a NUL character is interpreted as a 613 * string terminator, so all the following characters are set to 614 * spaces. 615 **/ 616void scsi_sanitize_inquiry_string(unsigned char *s, int len) 617{ 618 int terminated = 0; 619 620 for (; len > 0; (--len, ++s)) { 621 if (*s == 0) 622 terminated = 1; 623 if (terminated || *s < 0x20 || *s > 0x7e) 624 *s = ' '; 625 } 626} 627EXPORT_SYMBOL(scsi_sanitize_inquiry_string); 628 629 630/** 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 **/ 644static 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, resid; 651 struct scsi_failure failure_defs[] = { 652 /* 653 * not-ready to ready transition [asc/ascq=0x28/0x0] or 654 * power-on, reset [asc/ascq=0x29/0x0], continue. INQUIRY 655 * should not yield UNIT_ATTENTION but many buggy devices do 656 * so anyway. 657 */ 658 { 659 .sense = UNIT_ATTENTION, 660 .asc = 0x28, 661 .result = SAM_STAT_CHECK_CONDITION, 662 }, 663 { 664 .sense = UNIT_ATTENTION, 665 .asc = 0x29, 666 .result = SAM_STAT_CHECK_CONDITION, 667 }, 668 { 669 .allowed = 1, 670 .result = DID_TIME_OUT << 16, 671 }, 672 {} 673 }; 674 struct scsi_failures failures = { 675 .total_allowed = 3, 676 .failure_definitions = failure_defs, 677 }; 678 const struct scsi_exec_args exec_args = { 679 .resid = &resid, 680 .failures = &failures, 681 }; 682 683 *bflags = 0; 684 685 /* Perform up to 3 passes. The first pass uses a conservative 686 * transfer length of 36 unless sdev->inquiry_len specifies a 687 * different value. */ 688 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; 689 try_inquiry_len = first_inquiry_len; 690 pass = 1; 691 692 next_pass: 693 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 694 "scsi scan: INQUIRY pass %d length %d\n", 695 pass, try_inquiry_len)); 696 697 /* Each pass gets up to three chances to ignore Unit Attention */ 698 scsi_failures_reset_retries(&failures); 699 700 for (count = 0; count < 3; ++count) { 701 memset(scsi_cmd, 0, 6); 702 scsi_cmd[0] = INQUIRY; 703 scsi_cmd[4] = (unsigned char) try_inquiry_len; 704 705 memset(inq_result, 0, try_inquiry_len); 706 707 result = scsi_execute_cmd(sdev, scsi_cmd, REQ_OP_DRV_IN, 708 inq_result, try_inquiry_len, 709 HZ / 2 + HZ * scsi_inq_timeout, 3, 710 &exec_args); 711 712 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 713 "scsi scan: INQUIRY %s with code 0x%x\n", 714 result ? "failed" : "successful", result)); 715 716 if (result == 0) { 717 /* 718 * if nothing was transferred, we try 719 * again. It's a workaround for some USB 720 * devices. 721 */ 722 if (resid == try_inquiry_len) 723 continue; 724 } 725 break; 726 } 727 728 if (result == 0) { 729 scsi_sanitize_inquiry_string(&inq_result[8], 8); 730 scsi_sanitize_inquiry_string(&inq_result[16], 16); 731 scsi_sanitize_inquiry_string(&inq_result[32], 4); 732 733 response_len = inq_result[4] + 5; 734 if (response_len > 255) 735 response_len = first_inquiry_len; /* sanity */ 736 737 /* 738 * Get any flags for this device. 739 * 740 * XXX add a bflags to scsi_device, and replace the 741 * corresponding bit fields in scsi_device, so bflags 742 * need not be passed as an argument. 743 */ 744 *bflags = scsi_get_device_flags(sdev, &inq_result[8], 745 &inq_result[16]); 746 747 /* When the first pass succeeds we gain information about 748 * what larger transfer lengths might work. */ 749 if (pass == 1) { 750 if (BLIST_INQUIRY_36 & *bflags) 751 next_inquiry_len = 36; 752 /* 753 * LLD specified a maximum sdev->inquiry_len 754 * but device claims it has more data. Capping 755 * the length only makes sense for legacy 756 * devices. If a device supports SPC-4 (2014) 757 * or newer, assume that it is safe to ask for 758 * as much as the device says it supports. 759 */ 760 else if (sdev->inquiry_len && 761 response_len > sdev->inquiry_len && 762 (inq_result[2] & 0x7) < 6) /* SPC-4 */ 763 next_inquiry_len = sdev->inquiry_len; 764 else 765 next_inquiry_len = response_len; 766 767 /* If more data is available perform the second pass */ 768 if (next_inquiry_len > try_inquiry_len) { 769 try_inquiry_len = next_inquiry_len; 770 pass = 2; 771 goto next_pass; 772 } 773 } 774 775 } else if (pass == 2) { 776 sdev_printk(KERN_INFO, sdev, 777 "scsi scan: %d byte inquiry failed. " 778 "Consider BLIST_INQUIRY_36 for this device\n", 779 try_inquiry_len); 780 781 /* If this pass failed, the third pass goes back and transfers 782 * the same amount as we successfully got in the first pass. */ 783 try_inquiry_len = first_inquiry_len; 784 pass = 3; 785 goto next_pass; 786 } 787 788 /* If the last transfer attempt got an error, assume the 789 * peripheral doesn't exist or is dead. */ 790 if (result) 791 return -EIO; 792 793 /* Don't report any more data than the device says is valid */ 794 sdev->inquiry_len = min(try_inquiry_len, response_len); 795 796 /* 797 * XXX Abort if the response length is less than 36? If less than 798 * 32, the lookup of the device flags (above) could be invalid, 799 * and it would be possible to take an incorrect action - we do 800 * not want to hang because of a short INQUIRY. On the flip side, 801 * if the device is spun down or becoming ready (and so it gives a 802 * short INQUIRY), an abort here prevents any further use of the 803 * device, including spin up. 804 * 805 * On the whole, the best approach seems to be to assume the first 806 * 36 bytes are valid no matter what the device says. That's 807 * better than copying < 36 bytes to the inquiry-result buffer 808 * and displaying garbage for the Vendor, Product, or Revision 809 * strings. 810 */ 811 if (sdev->inquiry_len < 36) { 812 if (!sdev->host->short_inquiry) { 813 shost_printk(KERN_INFO, sdev->host, 814 "scsi scan: INQUIRY result too short (%d)," 815 " using 36\n", sdev->inquiry_len); 816 sdev->host->short_inquiry = 1; 817 } 818 sdev->inquiry_len = 36; 819 } 820 821 /* 822 * Related to the above issue: 823 * 824 * XXX Devices (disk or all?) should be sent a TEST UNIT READY, 825 * and if not ready, sent a START_STOP to start (maybe spin up) and 826 * then send the INQUIRY again, since the INQUIRY can change after 827 * a device is initialized. 828 * 829 * Ideally, start a device if explicitly asked to do so. This 830 * assumes that a device is spun up on power on, spun down on 831 * request, and then spun up on request. 832 */ 833 834 /* 835 * The scanning code needs to know the scsi_level, even if no 836 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so 837 * non-zero LUNs can be scanned. 838 */ 839 sdev->scsi_level = inq_result[2] & 0x0f; 840 if (sdev->scsi_level >= 2 || 841 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) 842 sdev->scsi_level++; 843 sdev->sdev_target->scsi_level = sdev->scsi_level; 844 845 /* 846 * If SCSI-2 or lower, and if the transport requires it, 847 * store the LUN value in CDB[1]. 848 */ 849 sdev->lun_in_cdb = 0; 850 if (sdev->scsi_level <= SCSI_2 && 851 sdev->scsi_level != SCSI_UNKNOWN && 852 !sdev->host->no_scsi2_lun_in_cdb) 853 sdev->lun_in_cdb = 1; 854 855 return 0; 856} 857 858/** 859 * scsi_add_lun - allocate and fully initialze a scsi_device 860 * @sdev: holds information to be stored in the new scsi_device 861 * @inq_result: holds the result of a previous INQUIRY to the LUN 862 * @bflags: black/white list flag 863 * @async: 1 if this device is being scanned asynchronously 864 * 865 * Description: 866 * Initialize the scsi_device @sdev. Optionally set fields based 867 * on values in *@bflags. 868 * 869 * Return: 870 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 871 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 872 **/ 873static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, 874 blist_flags_t *bflags, int async) 875{ 876 int ret; 877 878 /* 879 * XXX do not save the inquiry, since it can change underneath us, 880 * save just vendor/model/rev. 881 * 882 * Rather than save it and have an ioctl that retrieves the saved 883 * value, have an ioctl that executes the same INQUIRY code used 884 * in scsi_probe_lun, let user level programs doing INQUIRY 885 * scanning run at their own risk, or supply a user level program 886 * that can correctly scan. 887 */ 888 889 /* 890 * Copy at least 36 bytes of INQUIRY data, so that we don't 891 * dereference unallocated memory when accessing the Vendor, 892 * Product, and Revision strings. Badly behaved devices may set 893 * the INQUIRY Additional Length byte to a small value, indicating 894 * these strings are invalid, but often they contain plausible data 895 * nonetheless. It doesn't matter if the device sent < 36 bytes 896 * total, since scsi_probe_lun() initializes inq_result with 0s. 897 */ 898 sdev->inquiry = kmemdup(inq_result, 899 max_t(size_t, sdev->inquiry_len, 36), 900 GFP_KERNEL); 901 if (sdev->inquiry == NULL) 902 return SCSI_SCAN_NO_RESPONSE; 903 904 sdev->vendor = (char *) (sdev->inquiry + 8); 905 sdev->model = (char *) (sdev->inquiry + 16); 906 sdev->rev = (char *) (sdev->inquiry + 32); 907 908 if (strncmp(sdev->vendor, "ATA ", 8) == 0) { 909 /* 910 * sata emulation layer device. This is a hack to work around 911 * the SATL power management specifications which state that 912 * when the SATL detects the device has gone into standby 913 * mode, it shall respond with NOT READY. 914 */ 915 sdev->allow_restart = 1; 916 } 917 918 if (*bflags & BLIST_ISROM) { 919 sdev->type = TYPE_ROM; 920 sdev->removable = 1; 921 } else { 922 sdev->type = (inq_result[0] & 0x1f); 923 sdev->removable = (inq_result[1] & 0x80) >> 7; 924 925 /* 926 * some devices may respond with wrong type for 927 * well-known logical units. Force well-known type 928 * to enumerate them correctly. 929 */ 930 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) { 931 sdev_printk(KERN_WARNING, sdev, 932 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n", 933 __func__, sdev->type, (unsigned int)sdev->lun); 934 sdev->type = TYPE_WLUN; 935 } 936 937 } 938 939 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { 940 /* RBC and MMC devices can return SCSI-3 compliance and yet 941 * still not support REPORT LUNS, so make them act as 942 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is 943 * specifically set */ 944 if ((*bflags & BLIST_REPORTLUN2) == 0) 945 *bflags |= BLIST_NOREPORTLUN; 946 } 947 948 /* 949 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI 950 * spec says: The device server is capable of supporting the 951 * specified peripheral device type on this logical unit. However, 952 * the physical device is not currently connected to this logical 953 * unit. 954 * 955 * The above is vague, as it implies that we could treat 001 and 956 * 011 the same. Stay compatible with previous code, and create a 957 * scsi_device for a PQ of 1 958 * 959 * Don't set the device offline here; rather let the upper 960 * level drivers eval the PQ to decide whether they should 961 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. 962 */ 963 964 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; 965 sdev->lockable = sdev->removable; 966 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); 967 968 if (sdev->scsi_level >= SCSI_3 || 969 (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) 970 sdev->ppr = 1; 971 if (inq_result[7] & 0x60) 972 sdev->wdtr = 1; 973 if (inq_result[7] & 0x10) 974 sdev->sdtr = 1; 975 976 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " 977 "ANSI: %d%s\n", scsi_device_type(sdev->type), 978 sdev->vendor, sdev->model, sdev->rev, 979 sdev->inq_periph_qual, inq_result[2] & 0x07, 980 (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); 981 982 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && 983 !(*bflags & BLIST_NOTQ)) { 984 sdev->tagged_supported = 1; 985 sdev->simple_tags = 1; 986 } 987 988 /* 989 * Some devices (Texel CD ROM drives) have handshaking problems 990 * when used with the Seagate controllers. borken is initialized 991 * to 1, and then set it to 0 here. 992 */ 993 if ((*bflags & BLIST_BORKEN) == 0) 994 sdev->borken = 0; 995 996 if (*bflags & BLIST_NO_ULD_ATTACH) 997 sdev->no_uld_attach = 1; 998 999 /* 1000 * Apparently some really broken devices (contrary to the SCSI 1001 * standards) need to be selected without asserting ATN 1002 */ 1003 if (*bflags & BLIST_SELECT_NO_ATN) 1004 sdev->select_no_atn = 1; 1005 1006 /* 1007 * Maximum 512 sector transfer length 1008 * broken RA4x00 Compaq Disk Array 1009 */ 1010 if (*bflags & BLIST_MAX_512) 1011 blk_queue_max_hw_sectors(sdev->request_queue, 512); 1012 /* 1013 * Max 1024 sector transfer length for targets that report incorrect 1014 * max/optimal lengths and relied on the old block layer safe default 1015 */ 1016 else if (*bflags & BLIST_MAX_1024) 1017 blk_queue_max_hw_sectors(sdev->request_queue, 1024); 1018 1019 /* 1020 * Some devices may not want to have a start command automatically 1021 * issued when a device is added. 1022 */ 1023 if (*bflags & BLIST_NOSTARTONADD) 1024 sdev->no_start_on_add = 1; 1025 1026 if (*bflags & BLIST_SINGLELUN) 1027 scsi_target(sdev)->single_lun = 1; 1028 1029 sdev->use_10_for_rw = 1; 1030 1031 /* some devices don't like REPORT SUPPORTED OPERATION CODES 1032 * and will simply timeout causing sd_mod init to take a very 1033 * very long time */ 1034 if (*bflags & BLIST_NO_RSOC) 1035 sdev->no_report_opcodes = 1; 1036 1037 /* set the device running here so that slave configure 1038 * may do I/O */ 1039 mutex_lock(&sdev->state_mutex); 1040 ret = scsi_device_set_state(sdev, SDEV_RUNNING); 1041 if (ret) 1042 ret = scsi_device_set_state(sdev, SDEV_BLOCK); 1043 mutex_unlock(&sdev->state_mutex); 1044 1045 if (ret) { 1046 sdev_printk(KERN_ERR, sdev, 1047 "in wrong state %s to complete scan\n", 1048 scsi_device_state_name(sdev->sdev_state)); 1049 return SCSI_SCAN_NO_RESPONSE; 1050 } 1051 1052 if (*bflags & BLIST_NOT_LOCKABLE) 1053 sdev->lockable = 0; 1054 1055 if (*bflags & BLIST_RETRY_HWERROR) 1056 sdev->retry_hwerror = 1; 1057 1058 if (*bflags & BLIST_NO_DIF) 1059 sdev->no_dif = 1; 1060 1061 if (*bflags & BLIST_UNMAP_LIMIT_WS) 1062 sdev->unmap_limit_for_ws = 1; 1063 1064 if (*bflags & BLIST_IGN_MEDIA_CHANGE) 1065 sdev->ignore_media_change = 1; 1066 1067 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; 1068 1069 if (*bflags & BLIST_TRY_VPD_PAGES) 1070 sdev->try_vpd_pages = 1; 1071 else if (*bflags & BLIST_SKIP_VPD_PAGES) 1072 sdev->skip_vpd_pages = 1; 1073 1074 if (*bflags & BLIST_NO_VPD_SIZE) 1075 sdev->no_vpd_size = 1; 1076 1077 transport_configure_device(&sdev->sdev_gendev); 1078 1079 if (sdev->host->hostt->slave_configure) { 1080 ret = sdev->host->hostt->slave_configure(sdev); 1081 if (ret) { 1082 /* 1083 * if LLDD reports slave not present, don't clutter 1084 * console with alloc failure messages 1085 */ 1086 if (ret != -ENXIO) { 1087 sdev_printk(KERN_ERR, sdev, 1088 "failed to configure device\n"); 1089 } 1090 return SCSI_SCAN_NO_RESPONSE; 1091 } 1092 1093 /* 1094 * The queue_depth is often changed in ->slave_configure. 1095 * Set up budget map again since memory consumption of 1096 * the map depends on actual queue depth. 1097 */ 1098 scsi_realloc_sdev_budget_map(sdev, sdev->queue_depth); 1099 } 1100 1101 if (sdev->scsi_level >= SCSI_3) 1102 scsi_attach_vpd(sdev); 1103 1104 scsi_cdl_check(sdev); 1105 1106 sdev->max_queue_depth = sdev->queue_depth; 1107 WARN_ON_ONCE(sdev->max_queue_depth > sdev->budget_map.depth); 1108 sdev->sdev_bflags = *bflags; 1109 1110 /* 1111 * Ok, the device is now all set up, we can 1112 * register it and tell the rest of the kernel 1113 * about it. 1114 */ 1115 if (!async && scsi_sysfs_add_sdev(sdev) != 0) 1116 return SCSI_SCAN_NO_RESPONSE; 1117 1118 return SCSI_SCAN_LUN_PRESENT; 1119} 1120 1121#ifdef CONFIG_SCSI_LOGGING 1122/** 1123 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace 1124 * @buf: Output buffer with at least end-first+1 bytes of space 1125 * @inq: Inquiry buffer (input) 1126 * @first: Offset of string into inq 1127 * @end: Index after last character in inq 1128 */ 1129static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, 1130 unsigned first, unsigned end) 1131{ 1132 unsigned term = 0, idx; 1133 1134 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { 1135 if (inq[idx+first] > ' ') { 1136 buf[idx] = inq[idx+first]; 1137 term = idx+1; 1138 } else { 1139 buf[idx] = ' '; 1140 } 1141 } 1142 buf[term] = 0; 1143 return buf; 1144} 1145#endif 1146 1147/** 1148 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it 1149 * @starget: pointer to target device structure 1150 * @lun: LUN of target device 1151 * @bflagsp: store bflags here if not NULL 1152 * @sdevp: probe the LUN corresponding to this scsi_device 1153 * @rescan: if not equal to SCSI_SCAN_INITIAL skip some code only 1154 * needed on first scan 1155 * @hostdata: passed to scsi_alloc_sdev() 1156 * 1157 * Description: 1158 * Call scsi_probe_lun, if a LUN with an attached device is found, 1159 * allocate and set it up by calling scsi_add_lun. 1160 * 1161 * Return: 1162 * 1163 * - SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 1164 * - SCSI_SCAN_TARGET_PRESENT: target responded, but no device is 1165 * attached at the LUN 1166 * - SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 1167 **/ 1168static int scsi_probe_and_add_lun(struct scsi_target *starget, 1169 u64 lun, blist_flags_t *bflagsp, 1170 struct scsi_device **sdevp, 1171 enum scsi_scan_mode rescan, 1172 void *hostdata) 1173{ 1174 struct scsi_device *sdev; 1175 unsigned char *result; 1176 blist_flags_t bflags; 1177 int res = SCSI_SCAN_NO_RESPONSE, result_len = 256; 1178 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1179 1180 /* 1181 * The rescan flag is used as an optimization, the first scan of a 1182 * host adapter calls into here with rescan == 0. 1183 */ 1184 sdev = scsi_device_lookup_by_target(starget, lun); 1185 if (sdev) { 1186 if (rescan != SCSI_SCAN_INITIAL || !scsi_device_created(sdev)) { 1187 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1188 "scsi scan: device exists on %s\n", 1189 dev_name(&sdev->sdev_gendev))); 1190 if (sdevp) 1191 *sdevp = sdev; 1192 else 1193 scsi_device_put(sdev); 1194 1195 if (bflagsp) 1196 *bflagsp = scsi_get_device_flags(sdev, 1197 sdev->vendor, 1198 sdev->model); 1199 return SCSI_SCAN_LUN_PRESENT; 1200 } 1201 scsi_device_put(sdev); 1202 } else 1203 sdev = scsi_alloc_sdev(starget, lun, hostdata); 1204 if (!sdev) 1205 goto out; 1206 1207 result = kmalloc(result_len, GFP_KERNEL); 1208 if (!result) 1209 goto out_free_sdev; 1210 1211 if (scsi_probe_lun(sdev, result, result_len, &bflags)) 1212 goto out_free_result; 1213 1214 if (bflagsp) 1215 *bflagsp = bflags; 1216 /* 1217 * result contains valid SCSI INQUIRY data. 1218 */ 1219 if ((result[0] >> 5) == 3) { 1220 /* 1221 * For a Peripheral qualifier 3 (011b), the SCSI 1222 * spec says: The device server is not capable of 1223 * supporting a physical device on this logical 1224 * unit. 1225 * 1226 * For disks, this implies that there is no 1227 * logical disk configured at sdev->lun, but there 1228 * is a target id responding. 1229 */ 1230 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" 1231 " peripheral qualifier of 3, device not" 1232 " added\n")) 1233 if (lun == 0) { 1234 SCSI_LOG_SCAN_BUS(1, { 1235 unsigned char vend[9]; 1236 unsigned char mod[17]; 1237 1238 sdev_printk(KERN_INFO, sdev, 1239 "scsi scan: consider passing scsi_mod." 1240 "dev_flags=%s:%s:0x240 or 0x1000240\n", 1241 scsi_inq_str(vend, result, 8, 16), 1242 scsi_inq_str(mod, result, 16, 32)); 1243 }); 1244 1245 } 1246 1247 res = SCSI_SCAN_TARGET_PRESENT; 1248 goto out_free_result; 1249 } 1250 1251 /* 1252 * Some targets may set slight variations of PQ and PDT to signal 1253 * that no LUN is present, so don't add sdev in these cases. 1254 * Two specific examples are: 1255 * 1) NetApp targets: return PQ=1, PDT=0x1f 1256 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" 1257 * in the UFI 1.0 spec (we cannot rely on reserved bits). 1258 * 1259 * References: 1260 * 1) SCSI SPC-3, pp. 145-146 1261 * PQ=1: "A peripheral device having the specified peripheral 1262 * device type is not connected to this logical unit. However, the 1263 * device server is capable of supporting the specified peripheral 1264 * device type on this logical unit." 1265 * PDT=0x1f: "Unknown or no device type" 1266 * 2) USB UFI 1.0, p. 20 1267 * PDT=00h Direct-access device (floppy) 1268 * PDT=1Fh none (no FDD connected to the requested logical unit) 1269 */ 1270 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) && 1271 (result[0] & 0x1f) == 0x1f && 1272 !scsi_is_wlun(lun)) { 1273 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1274 "scsi scan: peripheral device type" 1275 " of 31, no device added\n")); 1276 res = SCSI_SCAN_TARGET_PRESENT; 1277 goto out_free_result; 1278 } 1279 1280 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); 1281 if (res == SCSI_SCAN_LUN_PRESENT) { 1282 if (bflags & BLIST_KEY) { 1283 sdev->lockable = 0; 1284 scsi_unlock_floptical(sdev, result); 1285 } 1286 } 1287 1288 out_free_result: 1289 kfree(result); 1290 out_free_sdev: 1291 if (res == SCSI_SCAN_LUN_PRESENT) { 1292 if (sdevp) { 1293 if (scsi_device_get(sdev) == 0) { 1294 *sdevp = sdev; 1295 } else { 1296 __scsi_remove_device(sdev); 1297 res = SCSI_SCAN_NO_RESPONSE; 1298 } 1299 } 1300 } else 1301 __scsi_remove_device(sdev); 1302 out: 1303 return res; 1304} 1305 1306/** 1307 * scsi_sequential_lun_scan - sequentially scan a SCSI target 1308 * @starget: pointer to target structure to scan 1309 * @bflags: black/white list flag for LUN 0 1310 * @scsi_level: Which version of the standard does this device adhere to 1311 * @rescan: passed to scsi_probe_add_lun() 1312 * 1313 * Description: 1314 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been 1315 * scanned) to some maximum lun until a LUN is found with no device 1316 * attached. Use the bflags to figure out any oddities. 1317 * 1318 * Modifies sdevscan->lun. 1319 **/ 1320static void scsi_sequential_lun_scan(struct scsi_target *starget, 1321 blist_flags_t bflags, int scsi_level, 1322 enum scsi_scan_mode rescan) 1323{ 1324 uint max_dev_lun; 1325 u64 sparse_lun, lun; 1326 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1327 1328 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget, 1329 "scsi scan: Sequential scan\n")); 1330 1331 max_dev_lun = min(max_scsi_luns, shost->max_lun); 1332 /* 1333 * If this device is known to support sparse multiple units, 1334 * override the other settings, and scan all of them. Normally, 1335 * SCSI-3 devices should be scanned via the REPORT LUNS. 1336 */ 1337 if (bflags & BLIST_SPARSELUN) { 1338 max_dev_lun = shost->max_lun; 1339 sparse_lun = 1; 1340 } else 1341 sparse_lun = 0; 1342 1343 /* 1344 * If less than SCSI_1_CCS, and no special lun scanning, stop 1345 * scanning; this matches 2.4 behaviour, but could just be a bug 1346 * (to continue scanning a SCSI_1_CCS device). 1347 * 1348 * This test is broken. We might not have any device on lun0 for 1349 * a sparselun device, and if that's the case then how would we 1350 * know the real scsi_level, eh? It might make sense to just not 1351 * scan any SCSI_1 device for non-0 luns, but that check would best 1352 * go into scsi_alloc_sdev() and just have it return null when asked 1353 * to alloc an sdev for lun > 0 on an already found SCSI_1 device. 1354 * 1355 if ((sdevscan->scsi_level < SCSI_1_CCS) && 1356 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) 1357 == 0)) 1358 return; 1359 */ 1360 /* 1361 * If this device is known to support multiple units, override 1362 * the other settings, and scan all of them. 1363 */ 1364 if (bflags & BLIST_FORCELUN) 1365 max_dev_lun = shost->max_lun; 1366 /* 1367 * REGAL CDC-4X: avoid hang after LUN 4 1368 */ 1369 if (bflags & BLIST_MAX5LUN) 1370 max_dev_lun = min(5U, max_dev_lun); 1371 /* 1372 * Do not scan SCSI-2 or lower device past LUN 7, unless 1373 * BLIST_LARGELUN. 1374 */ 1375 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) 1376 max_dev_lun = min(8U, max_dev_lun); 1377 else 1378 max_dev_lun = min(256U, max_dev_lun); 1379 1380 /* 1381 * We have already scanned LUN 0, so start at LUN 1. Keep scanning 1382 * until we reach the max, or no LUN is found and we are not 1383 * sparse_lun. 1384 */ 1385 for (lun = 1; lun < max_dev_lun; ++lun) 1386 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, 1387 NULL) != SCSI_SCAN_LUN_PRESENT) && 1388 !sparse_lun) 1389 return; 1390} 1391 1392/** 1393 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results 1394 * @starget: which target 1395 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN 1396 * @rescan: nonzero if we can skip code only needed on first scan 1397 * 1398 * Description: 1399 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. 1400 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. 1401 * 1402 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 1403 * LUNs even if it's older than SCSI-3. 1404 * If BLIST_NOREPORTLUN is set, return 1 always. 1405 * If BLIST_NOLUN is set, return 0 always. 1406 * If starget->no_report_luns is set, return 1 always. 1407 * 1408 * Return: 1409 * 0: scan completed (or no memory, so further scanning is futile) 1410 * 1: could not scan with REPORT LUN 1411 **/ 1412static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflags, 1413 enum scsi_scan_mode rescan) 1414{ 1415 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 1416 unsigned int length; 1417 u64 lun; 1418 unsigned int num_luns; 1419 int result; 1420 struct scsi_lun *lunp, *lun_data; 1421 struct scsi_device *sdev; 1422 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 1423 struct scsi_failure failure_defs[] = { 1424 { 1425 .sense = UNIT_ATTENTION, 1426 .asc = SCMD_FAILURE_ASC_ANY, 1427 .ascq = SCMD_FAILURE_ASCQ_ANY, 1428 .result = SAM_STAT_CHECK_CONDITION, 1429 }, 1430 /* Fail all CCs except the UA above */ 1431 { 1432 .sense = SCMD_FAILURE_SENSE_ANY, 1433 .result = SAM_STAT_CHECK_CONDITION, 1434 }, 1435 /* Retry any other errors not listed above */ 1436 { 1437 .result = SCMD_FAILURE_RESULT_ANY, 1438 }, 1439 {} 1440 }; 1441 struct scsi_failures failures = { 1442 .total_allowed = 3, 1443 .failure_definitions = failure_defs, 1444 }; 1445 const struct scsi_exec_args exec_args = { 1446 .failures = &failures, 1447 }; 1448 int ret = 0; 1449 1450 /* 1451 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. 1452 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does 1453 * support more than 8 LUNs. 1454 * Don't attempt if the target doesn't support REPORT LUNS. 1455 */ 1456 if (bflags & BLIST_NOREPORTLUN) 1457 return 1; 1458 if (starget->scsi_level < SCSI_2 && 1459 starget->scsi_level != SCSI_UNKNOWN) 1460 return 1; 1461 if (starget->scsi_level < SCSI_3 && 1462 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) 1463 return 1; 1464 if (bflags & BLIST_NOLUN) 1465 return 0; 1466 if (starget->no_report_luns) 1467 return 1; 1468 1469 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { 1470 sdev = scsi_alloc_sdev(starget, 0, NULL); 1471 if (!sdev) 1472 return 0; 1473 if (scsi_device_get(sdev)) { 1474 __scsi_remove_device(sdev); 1475 return 0; 1476 } 1477 } 1478 1479 /* 1480 * Allocate enough to hold the header (the same size as one scsi_lun) 1481 * plus the number of luns we are requesting. 511 was the default 1482 * value of the now removed max_report_luns parameter. 1483 */ 1484 length = (511 + 1) * sizeof(struct scsi_lun); 1485retry: 1486 lun_data = kmalloc(length, GFP_KERNEL); 1487 if (!lun_data) { 1488 printk(ALLOC_FAILURE_MSG, __func__); 1489 goto out; 1490 } 1491 1492 scsi_cmd[0] = REPORT_LUNS; 1493 1494 /* 1495 * bytes 1 - 5: reserved, set to zero. 1496 */ 1497 memset(&scsi_cmd[1], 0, 5); 1498 1499 /* 1500 * bytes 6 - 9: length of the command. 1501 */ 1502 put_unaligned_be32(length, &scsi_cmd[6]); 1503 1504 scsi_cmd[10] = 0; /* reserved */ 1505 scsi_cmd[11] = 0; /* control */ 1506 1507 /* 1508 * We can get a UNIT ATTENTION, for example a power on/reset, so 1509 * retry a few times (like sd.c does for TEST UNIT READY). 1510 * Experience shows some combinations of adapter/devices get at 1511 * least two power on/resets. 1512 * 1513 * Illegal requests (for devices that do not support REPORT LUNS) 1514 * should come through as a check condition, and will not generate 1515 * a retry. 1516 */ 1517 scsi_failures_reset_retries(&failures); 1518 1519 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1520 "scsi scan: Sending REPORT LUNS\n")); 1521 1522 result = scsi_execute_cmd(sdev, scsi_cmd, REQ_OP_DRV_IN, lun_data, 1523 length, SCSI_REPORT_LUNS_TIMEOUT, 3, 1524 &exec_args); 1525 1526 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1527 "scsi scan: REPORT LUNS %s result 0x%x\n", 1528 result ? "failed" : "successful", result)); 1529 if (result) { 1530 /* 1531 * The device probably does not support a REPORT LUN command 1532 */ 1533 ret = 1; 1534 goto out_err; 1535 } 1536 1537 /* 1538 * Get the length from the first four bytes of lun_data. 1539 */ 1540 if (get_unaligned_be32(lun_data->scsi_lun) + 1541 sizeof(struct scsi_lun) > length) { 1542 length = get_unaligned_be32(lun_data->scsi_lun) + 1543 sizeof(struct scsi_lun); 1544 kfree(lun_data); 1545 goto retry; 1546 } 1547 length = get_unaligned_be32(lun_data->scsi_lun); 1548 1549 num_luns = (length / sizeof(struct scsi_lun)); 1550 1551 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1552 "scsi scan: REPORT LUN scan\n")); 1553 1554 /* 1555 * Scan the luns in lun_data. The entry at offset 0 is really 1556 * the header, so start at 1 and go up to and including num_luns. 1557 */ 1558 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { 1559 lun = scsilun_to_int(lunp); 1560 1561 if (lun > sdev->host->max_lun) { 1562 sdev_printk(KERN_WARNING, sdev, 1563 "lun%llu has a LUN larger than" 1564 " allowed by the host adapter\n", lun); 1565 } else { 1566 int res; 1567 1568 res = scsi_probe_and_add_lun(starget, 1569 lun, NULL, NULL, rescan, NULL); 1570 if (res == SCSI_SCAN_NO_RESPONSE) { 1571 /* 1572 * Got some results, but now none, abort. 1573 */ 1574 sdev_printk(KERN_ERR, sdev, 1575 "Unexpected response" 1576 " from lun %llu while scanning, scan" 1577 " aborted\n", (unsigned long long)lun); 1578 break; 1579 } 1580 } 1581 } 1582 1583 out_err: 1584 kfree(lun_data); 1585 out: 1586 if (scsi_device_created(sdev)) 1587 /* 1588 * the sdev we used didn't appear in the report luns scan 1589 */ 1590 __scsi_remove_device(sdev); 1591 scsi_device_put(sdev); 1592 return ret; 1593} 1594 1595struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, 1596 uint id, u64 lun, void *hostdata) 1597{ 1598 struct scsi_device *sdev = ERR_PTR(-ENODEV); 1599 struct device *parent = &shost->shost_gendev; 1600 struct scsi_target *starget; 1601 1602 if (strncmp(scsi_scan_type, "none", 4) == 0) 1603 return ERR_PTR(-ENODEV); 1604 1605 starget = scsi_alloc_target(parent, channel, id); 1606 if (!starget) 1607 return ERR_PTR(-ENOMEM); 1608 scsi_autopm_get_target(starget); 1609 1610 mutex_lock(&shost->scan_mutex); 1611 if (!shost->async_scan) 1612 scsi_complete_async_scans(); 1613 1614 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1615 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1616 SCSI_SCAN_RESCAN, hostdata); 1617 scsi_autopm_put_host(shost); 1618 } 1619 mutex_unlock(&shost->scan_mutex); 1620 scsi_autopm_put_target(starget); 1621 /* 1622 * paired with scsi_alloc_target(). Target will be destroyed unless 1623 * scsi_probe_and_add_lun made an underlying device visible 1624 */ 1625 scsi_target_reap(starget); 1626 put_device(&starget->dev); 1627 1628 return sdev; 1629} 1630EXPORT_SYMBOL(__scsi_add_device); 1631 1632int scsi_add_device(struct Scsi_Host *host, uint channel, 1633 uint target, u64 lun) 1634{ 1635 struct scsi_device *sdev = 1636 __scsi_add_device(host, channel, target, lun, NULL); 1637 if (IS_ERR(sdev)) 1638 return PTR_ERR(sdev); 1639 1640 scsi_device_put(sdev); 1641 return 0; 1642} 1643EXPORT_SYMBOL(scsi_add_device); 1644 1645int scsi_resume_device(struct scsi_device *sdev) 1646{ 1647 struct device *dev = &sdev->sdev_gendev; 1648 int ret = 0; 1649 1650 device_lock(dev); 1651 1652 /* 1653 * Bail out if the device or its queue are not running. Otherwise, 1654 * the rescan may block waiting for commands to be executed, with us 1655 * holding the device lock. This can result in a potential deadlock 1656 * in the power management core code when system resume is on-going. 1657 */ 1658 if (sdev->sdev_state != SDEV_RUNNING || 1659 blk_queue_pm_only(sdev->request_queue)) { 1660 ret = -EWOULDBLOCK; 1661 goto unlock; 1662 } 1663 1664 if (dev->driver && try_module_get(dev->driver->owner)) { 1665 struct scsi_driver *drv = to_scsi_driver(dev->driver); 1666 1667 if (drv->resume) 1668 ret = drv->resume(dev); 1669 module_put(dev->driver->owner); 1670 } 1671 1672unlock: 1673 device_unlock(dev); 1674 1675 return ret; 1676} 1677EXPORT_SYMBOL(scsi_resume_device); 1678 1679int scsi_rescan_device(struct scsi_device *sdev) 1680{ 1681 struct device *dev = &sdev->sdev_gendev; 1682 int ret = 0; 1683 1684 device_lock(dev); 1685 1686 /* 1687 * Bail out if the device or its queue are not running. Otherwise, 1688 * the rescan may block waiting for commands to be executed, with us 1689 * holding the device lock. This can result in a potential deadlock 1690 * in the power management core code when system resume is on-going. 1691 */ 1692 if (sdev->sdev_state != SDEV_RUNNING || 1693 blk_queue_pm_only(sdev->request_queue)) { 1694 ret = -EWOULDBLOCK; 1695 goto unlock; 1696 } 1697 1698 scsi_attach_vpd(sdev); 1699 scsi_cdl_check(sdev); 1700 1701 if (sdev->handler && sdev->handler->rescan) 1702 sdev->handler->rescan(sdev); 1703 1704 if (dev->driver && try_module_get(dev->driver->owner)) { 1705 struct scsi_driver *drv = to_scsi_driver(dev->driver); 1706 1707 if (drv->rescan) 1708 drv->rescan(dev); 1709 module_put(dev->driver->owner); 1710 } 1711 1712unlock: 1713 device_unlock(dev); 1714 1715 return ret; 1716} 1717EXPORT_SYMBOL(scsi_rescan_device); 1718 1719static void __scsi_scan_target(struct device *parent, unsigned int channel, 1720 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1721{ 1722 struct Scsi_Host *shost = dev_to_shost(parent); 1723 blist_flags_t bflags = 0; 1724 int res; 1725 struct scsi_target *starget; 1726 1727 if (shost->this_id == id) 1728 /* 1729 * Don't scan the host adapter 1730 */ 1731 return; 1732 1733 starget = scsi_alloc_target(parent, channel, id); 1734 if (!starget) 1735 return; 1736 scsi_autopm_get_target(starget); 1737 1738 if (lun != SCAN_WILD_CARD) { 1739 /* 1740 * Scan for a specific host/chan/id/lun. 1741 */ 1742 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); 1743 goto out_reap; 1744 } 1745 1746 /* 1747 * Scan LUN 0, if there is some response, scan further. Ideally, we 1748 * would not configure LUN 0 until all LUNs are scanned. 1749 */ 1750 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); 1751 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { 1752 if (scsi_report_lun_scan(starget, bflags, rescan) != 0) 1753 /* 1754 * The REPORT LUN did not scan the target, 1755 * do a sequential scan. 1756 */ 1757 scsi_sequential_lun_scan(starget, bflags, 1758 starget->scsi_level, rescan); 1759 } 1760 1761 out_reap: 1762 scsi_autopm_put_target(starget); 1763 /* 1764 * paired with scsi_alloc_target(): determine if the target has 1765 * any children at all and if not, nuke it 1766 */ 1767 scsi_target_reap(starget); 1768 1769 put_device(&starget->dev); 1770} 1771 1772/** 1773 * scsi_scan_target - scan a target id, possibly including all LUNs on the target. 1774 * @parent: host to scan 1775 * @channel: channel to scan 1776 * @id: target id to scan 1777 * @lun: Specific LUN to scan or SCAN_WILD_CARD 1778 * @rescan: passed to LUN scanning routines; SCSI_SCAN_INITIAL for 1779 * no rescan, SCSI_SCAN_RESCAN to rescan existing LUNs, 1780 * and SCSI_SCAN_MANUAL to force scanning even if 1781 * 'scan=manual' is set. 1782 * 1783 * Description: 1784 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, 1785 * and possibly all LUNs on the target id. 1786 * 1787 * First try a REPORT LUN scan, if that does not scan the target, do a 1788 * sequential scan of LUNs on the target id. 1789 **/ 1790void scsi_scan_target(struct device *parent, unsigned int channel, 1791 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1792{ 1793 struct Scsi_Host *shost = dev_to_shost(parent); 1794 1795 if (strncmp(scsi_scan_type, "none", 4) == 0) 1796 return; 1797 1798 if (rescan != SCSI_SCAN_MANUAL && 1799 strncmp(scsi_scan_type, "manual", 6) == 0) 1800 return; 1801 1802 mutex_lock(&shost->scan_mutex); 1803 if (!shost->async_scan) 1804 scsi_complete_async_scans(); 1805 1806 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1807 __scsi_scan_target(parent, channel, id, lun, rescan); 1808 scsi_autopm_put_host(shost); 1809 } 1810 mutex_unlock(&shost->scan_mutex); 1811} 1812EXPORT_SYMBOL(scsi_scan_target); 1813 1814static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, 1815 unsigned int id, u64 lun, 1816 enum scsi_scan_mode rescan) 1817{ 1818 uint order_id; 1819 1820 if (id == SCAN_WILD_CARD) 1821 for (id = 0; id < shost->max_id; ++id) { 1822 /* 1823 * XXX adapter drivers when possible (FCP, iSCSI) 1824 * could modify max_id to match the current max, 1825 * not the absolute max. 1826 * 1827 * XXX add a shost id iterator, so for example, 1828 * the FC ID can be the same as a target id 1829 * without a huge overhead of sparse id's. 1830 */ 1831 if (shost->reverse_ordering) 1832 /* 1833 * Scan from high to low id. 1834 */ 1835 order_id = shost->max_id - id - 1; 1836 else 1837 order_id = id; 1838 __scsi_scan_target(&shost->shost_gendev, channel, 1839 order_id, lun, rescan); 1840 } 1841 else 1842 __scsi_scan_target(&shost->shost_gendev, channel, 1843 id, lun, rescan); 1844} 1845 1846int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, 1847 unsigned int id, u64 lun, 1848 enum scsi_scan_mode rescan) 1849{ 1850 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, 1851 "%s: <%u:%u:%llu>\n", 1852 __func__, channel, id, lun)); 1853 1854 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || 1855 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || 1856 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun))) 1857 return -EINVAL; 1858 1859 mutex_lock(&shost->scan_mutex); 1860 if (!shost->async_scan) 1861 scsi_complete_async_scans(); 1862 1863 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1864 if (channel == SCAN_WILD_CARD) 1865 for (channel = 0; channel <= shost->max_channel; 1866 channel++) 1867 scsi_scan_channel(shost, channel, id, lun, 1868 rescan); 1869 else 1870 scsi_scan_channel(shost, channel, id, lun, rescan); 1871 scsi_autopm_put_host(shost); 1872 } 1873 mutex_unlock(&shost->scan_mutex); 1874 1875 return 0; 1876} 1877 1878static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 1879{ 1880 struct scsi_device *sdev; 1881 shost_for_each_device(sdev, shost) { 1882 /* target removed before the device could be added */ 1883 if (sdev->sdev_state == SDEV_DEL) 1884 continue; 1885 /* If device is already visible, skip adding it to sysfs */ 1886 if (sdev->is_visible) 1887 continue; 1888 if (!scsi_host_scan_allowed(shost) || 1889 scsi_sysfs_add_sdev(sdev) != 0) 1890 __scsi_remove_device(sdev); 1891 } 1892} 1893 1894/** 1895 * scsi_prep_async_scan - prepare for an async scan 1896 * @shost: the host which will be scanned 1897 * Returns: a cookie to be passed to scsi_finish_async_scan() 1898 * 1899 * Tells the midlayer this host is going to do an asynchronous scan. 1900 * It reserves the host's position in the scanning list and ensures 1901 * that other asynchronous scans started after this one won't affect the 1902 * ordering of the discovered devices. 1903 */ 1904static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 1905{ 1906 struct async_scan_data *data = NULL; 1907 unsigned long flags; 1908 1909 if (strncmp(scsi_scan_type, "sync", 4) == 0) 1910 return NULL; 1911 1912 mutex_lock(&shost->scan_mutex); 1913 if (shost->async_scan) { 1914 shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__); 1915 goto err; 1916 } 1917 1918 data = kmalloc(sizeof(*data), GFP_KERNEL); 1919 if (!data) 1920 goto err; 1921 data->shost = scsi_host_get(shost); 1922 if (!data->shost) 1923 goto err; 1924 init_completion(&data->prev_finished); 1925 1926 spin_lock_irqsave(shost->host_lock, flags); 1927 shost->async_scan = 1; 1928 spin_unlock_irqrestore(shost->host_lock, flags); 1929 mutex_unlock(&shost->scan_mutex); 1930 1931 spin_lock(&async_scan_lock); 1932 if (list_empty(&scanning_hosts)) 1933 complete(&data->prev_finished); 1934 list_add_tail(&data->list, &scanning_hosts); 1935 spin_unlock(&async_scan_lock); 1936 1937 return data; 1938 1939 err: 1940 mutex_unlock(&shost->scan_mutex); 1941 kfree(data); 1942 return NULL; 1943} 1944 1945/** 1946 * scsi_finish_async_scan - asynchronous scan has finished 1947 * @data: cookie returned from earlier call to scsi_prep_async_scan() 1948 * 1949 * All the devices currently attached to this host have been found. 1950 * This function announces all the devices it has found to the rest 1951 * of the system. 1952 */ 1953static void scsi_finish_async_scan(struct async_scan_data *data) 1954{ 1955 struct Scsi_Host *shost; 1956 unsigned long flags; 1957 1958 if (!data) 1959 return; 1960 1961 shost = data->shost; 1962 1963 mutex_lock(&shost->scan_mutex); 1964 1965 if (!shost->async_scan) { 1966 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1967 dump_stack(); 1968 mutex_unlock(&shost->scan_mutex); 1969 return; 1970 } 1971 1972 wait_for_completion(&data->prev_finished); 1973 1974 scsi_sysfs_add_devices(shost); 1975 1976 spin_lock_irqsave(shost->host_lock, flags); 1977 shost->async_scan = 0; 1978 spin_unlock_irqrestore(shost->host_lock, flags); 1979 1980 mutex_unlock(&shost->scan_mutex); 1981 1982 spin_lock(&async_scan_lock); 1983 list_del(&data->list); 1984 if (!list_empty(&scanning_hosts)) { 1985 struct async_scan_data *next = list_entry(scanning_hosts.next, 1986 struct async_scan_data, list); 1987 complete(&next->prev_finished); 1988 } 1989 spin_unlock(&async_scan_lock); 1990 1991 scsi_autopm_put_host(shost); 1992 scsi_host_put(shost); 1993 kfree(data); 1994} 1995 1996static void do_scsi_scan_host(struct Scsi_Host *shost) 1997{ 1998 if (shost->hostt->scan_finished) { 1999 unsigned long start = jiffies; 2000 if (shost->hostt->scan_start) 2001 shost->hostt->scan_start(shost); 2002 2003 while (!shost->hostt->scan_finished(shost, jiffies - start)) 2004 msleep(10); 2005 } else { 2006 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, 2007 SCAN_WILD_CARD, SCSI_SCAN_INITIAL); 2008 } 2009} 2010 2011static void do_scan_async(void *_data, async_cookie_t c) 2012{ 2013 struct async_scan_data *data = _data; 2014 struct Scsi_Host *shost = data->shost; 2015 2016 do_scsi_scan_host(shost); 2017 scsi_finish_async_scan(data); 2018} 2019 2020/** 2021 * scsi_scan_host - scan the given adapter 2022 * @shost: adapter to scan 2023 **/ 2024void scsi_scan_host(struct Scsi_Host *shost) 2025{ 2026 struct async_scan_data *data; 2027 2028 if (strncmp(scsi_scan_type, "none", 4) == 0 || 2029 strncmp(scsi_scan_type, "manual", 6) == 0) 2030 return; 2031 if (scsi_autopm_get_host(shost) < 0) 2032 return; 2033 2034 data = scsi_prep_async_scan(shost); 2035 if (!data) { 2036 do_scsi_scan_host(shost); 2037 scsi_autopm_put_host(shost); 2038 return; 2039 } 2040 2041 /* register with the async subsystem so wait_for_device_probe() 2042 * will flush this work 2043 */ 2044 async_schedule(do_scan_async, data); 2045 2046 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */ 2047} 2048EXPORT_SYMBOL(scsi_scan_host); 2049 2050void scsi_forget_host(struct Scsi_Host *shost) 2051{ 2052 struct scsi_device *sdev; 2053 unsigned long flags; 2054 2055 restart: 2056 spin_lock_irqsave(shost->host_lock, flags); 2057 list_for_each_entry(sdev, &shost->__devices, siblings) { 2058 if (sdev->sdev_state == SDEV_DEL) 2059 continue; 2060 spin_unlock_irqrestore(shost->host_lock, flags); 2061 __scsi_remove_device(sdev); 2062 goto restart; 2063 } 2064 spin_unlock_irqrestore(shost->host_lock, flags); 2065} 2066 2067