1 /* 2 * scsi_scan.c 3 * 4 * Copyright (C) 2000 Eric Youngdale, 5 * Copyright (C) 2002 Patrick Mansfield 6 * 7 * The general scanning/probing algorithm is as follows, exceptions are 8 * made to it depending on device specific flags, compilation options, and 9 * global variable (boot or module load time) settings. 10 * 11 * A specific LUN is scanned via an INQUIRY command; if the LUN has a 12 * device attached, a scsi_device is allocated and setup for it. 13 * 14 * For every id of every channel on the given host: 15 * 16 * Scan LUN 0; if the target responds to LUN 0 (even if there is no 17 * device or storage attached to LUN 0): 18 * 19 * If LUN 0 has a device attached, allocate and setup a 20 * scsi_device for it. 21 * 22 * If target is SCSI-3 or up, issue a REPORT LUN, and scan 23 * all of the LUNs returned by the REPORT LUN; else, 24 * sequentially scan LUNs up until some maximum is reached, 25 * or a LUN is seen that cannot have a device attached to it. 26 */ 27 28 #include <linux/module.h> 29 #include <linux/moduleparam.h> 30 #include <linux/init.h> 31 #include <linux/blkdev.h> 32 #include <linux/delay.h> 33 #include <linux/kthread.h> 34 #include <linux/spinlock.h> 35 #include <linux/async.h> 36 #include <linux/slab.h> 37 #include <asm/unaligned.h> 38 39 #include <scsi/scsi.h> 40 #include <scsi/scsi_cmnd.h> 41 #include <scsi/scsi_device.h> 42 #include <scsi/scsi_driver.h> 43 #include <scsi/scsi_devinfo.h> 44 #include <scsi/scsi_host.h> 45 #include <scsi/scsi_transport.h> 46 #include <scsi/scsi_eh.h> 47 48 #include "scsi_priv.h" 49 #include "scsi_logging.h" 50 51 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \ 52 " SCSI scanning, some SCSI devices might not be configured\n" 53 54 /* 55 * Default timeout 56 */ 57 #define SCSI_TIMEOUT (2*HZ) 58 59 /* 60 * Prefix values for the SCSI id's (stored in sysfs name field) 61 */ 62 #define SCSI_UID_SER_NUM 'S' 63 #define SCSI_UID_UNKNOWN 'Z' 64 65 /* 66 * Return values of some of the scanning functions. 67 * 68 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this 69 * includes allocation or general failures preventing IO from being sent. 70 * 71 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available 72 * on the given LUN. 73 * 74 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a 75 * given LUN. 76 */ 77 #define SCSI_SCAN_NO_RESPONSE 0 78 #define SCSI_SCAN_TARGET_PRESENT 1 79 #define SCSI_SCAN_LUN_PRESENT 2 80 81 static const char *scsi_null_device_strs = "nullnullnullnull"; 82 83 #define MAX_SCSI_LUNS 512 84 85 static u64 max_scsi_luns = MAX_SCSI_LUNS; 86 87 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR); 88 MODULE_PARM_DESC(max_luns, 89 "last scsi LUN (should be between 1 and 2^64-1)"); 90 91 #ifdef CONFIG_SCSI_SCAN_ASYNC 92 #define SCSI_SCAN_TYPE_DEFAULT "async" 93 #else 94 #define SCSI_SCAN_TYPE_DEFAULT "sync" 95 #endif 96 97 char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT; 98 99 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO); 100 MODULE_PARM_DESC(scan, "sync, async or none"); 101 102 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18; 103 104 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); 105 MODULE_PARM_DESC(inq_timeout, 106 "Timeout (in seconds) waiting for devices to answer INQUIRY." 107 " Default is 20. Some devices may need more; most need less."); 108 109 /* This lock protects only this list */ 110 static DEFINE_SPINLOCK(async_scan_lock); 111 static LIST_HEAD(scanning_hosts); 112 113 struct async_scan_data { 114 struct list_head list; 115 struct Scsi_Host *shost; 116 struct completion prev_finished; 117 }; 118 119 /** 120 * scsi_complete_async_scans - Wait for asynchronous scans to complete 121 * 122 * When this function returns, any host which started scanning before 123 * this function was called will have finished its scan. Hosts which 124 * started scanning after this function was called may or may not have 125 * finished. 126 */ 127 int scsi_complete_async_scans(void) 128 { 129 struct async_scan_data *data; 130 131 do { 132 if (list_empty(&scanning_hosts)) 133 return 0; 134 /* If we can't get memory immediately, that's OK. Just 135 * sleep a little. Even if we never get memory, the async 136 * scans will finish eventually. 137 */ 138 data = kmalloc(sizeof(*data), GFP_KERNEL); 139 if (!data) 140 msleep(1); 141 } while (!data); 142 143 data->shost = NULL; 144 init_completion(&data->prev_finished); 145 146 spin_lock(&async_scan_lock); 147 /* Check that there's still somebody else on the list */ 148 if (list_empty(&scanning_hosts)) 149 goto done; 150 list_add_tail(&data->list, &scanning_hosts); 151 spin_unlock(&async_scan_lock); 152 153 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); 154 wait_for_completion(&data->prev_finished); 155 156 spin_lock(&async_scan_lock); 157 list_del(&data->list); 158 if (!list_empty(&scanning_hosts)) { 159 struct async_scan_data *next = list_entry(scanning_hosts.next, 160 struct async_scan_data, list); 161 complete(&next->prev_finished); 162 } 163 done: 164 spin_unlock(&async_scan_lock); 165 166 kfree(data); 167 return 0; 168 } 169 170 /** 171 * scsi_unlock_floptical - unlock device via a special MODE SENSE command 172 * @sdev: scsi device to send command to 173 * @result: area to store the result of the MODE SENSE 174 * 175 * Description: 176 * Send a vendor specific MODE SENSE (not a MODE SELECT) command. 177 * Called for BLIST_KEY devices. 178 **/ 179 static void scsi_unlock_floptical(struct scsi_device *sdev, 180 unsigned char *result) 181 { 182 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 183 184 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n"); 185 scsi_cmd[0] = MODE_SENSE; 186 scsi_cmd[1] = 0; 187 scsi_cmd[2] = 0x2e; 188 scsi_cmd[3] = 0; 189 scsi_cmd[4] = 0x2a; /* size */ 190 scsi_cmd[5] = 0; 191 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, 192 SCSI_TIMEOUT, 3, NULL); 193 } 194 195 /** 196 * scsi_alloc_sdev - allocate and setup a scsi_Device 197 * @starget: which target to allocate a &scsi_device for 198 * @lun: which lun 199 * @hostdata: usually NULL and set by ->slave_alloc instead 200 * 201 * Description: 202 * Allocate, initialize for io, and return a pointer to a scsi_Device. 203 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and 204 * adds scsi_Device to the appropriate list. 205 * 206 * Return value: 207 * scsi_Device pointer, or NULL on failure. 208 **/ 209 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, 210 u64 lun, void *hostdata) 211 { 212 struct scsi_device *sdev; 213 int display_failure_msg = 1, ret; 214 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 215 extern void scsi_evt_thread(struct work_struct *work); 216 extern void scsi_requeue_run_queue(struct work_struct *work); 217 218 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, 219 GFP_ATOMIC); 220 if (!sdev) 221 goto out; 222 223 sdev->vendor = scsi_null_device_strs; 224 sdev->model = scsi_null_device_strs; 225 sdev->rev = scsi_null_device_strs; 226 sdev->host = shost; 227 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD; 228 sdev->id = starget->id; 229 sdev->lun = lun; 230 sdev->channel = starget->channel; 231 sdev->sdev_state = SDEV_CREATED; 232 INIT_LIST_HEAD(&sdev->siblings); 233 INIT_LIST_HEAD(&sdev->same_target_siblings); 234 INIT_LIST_HEAD(&sdev->cmd_list); 235 INIT_LIST_HEAD(&sdev->starved_entry); 236 INIT_LIST_HEAD(&sdev->event_list); 237 spin_lock_init(&sdev->list_lock); 238 INIT_WORK(&sdev->event_work, scsi_evt_thread); 239 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue); 240 241 sdev->sdev_gendev.parent = get_device(&starget->dev); 242 sdev->sdev_target = starget; 243 244 /* usually NULL and set by ->slave_alloc instead */ 245 sdev->hostdata = hostdata; 246 247 /* if the device needs this changing, it may do so in the 248 * slave_configure function */ 249 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; 250 251 /* 252 * Some low level driver could use device->type 253 */ 254 sdev->type = -1; 255 256 /* 257 * Assume that the device will have handshaking problems, 258 * and then fix this field later if it turns out it 259 * doesn't 260 */ 261 sdev->borken = 1; 262 263 if (shost_use_blk_mq(shost)) 264 sdev->request_queue = scsi_mq_alloc_queue(sdev); 265 else 266 sdev->request_queue = scsi_alloc_queue(sdev); 267 if (!sdev->request_queue) { 268 /* release fn is set up in scsi_sysfs_device_initialise, so 269 * have to free and put manually here */ 270 put_device(&starget->dev); 271 kfree(sdev); 272 goto out; 273 } 274 WARN_ON_ONCE(!blk_get_queue(sdev->request_queue)); 275 sdev->request_queue->queuedata = sdev; 276 277 if (!shost_use_blk_mq(sdev->host) && 278 (shost->bqt || shost->hostt->use_blk_tags)) { 279 blk_queue_init_tags(sdev->request_queue, 280 sdev->host->cmd_per_lun, shost->bqt, 281 shost->hostt->tag_alloc_policy); 282 } 283 scsi_change_queue_depth(sdev, sdev->host->cmd_per_lun); 284 285 scsi_sysfs_device_initialize(sdev); 286 287 if (shost->hostt->slave_alloc) { 288 ret = shost->hostt->slave_alloc(sdev); 289 if (ret) { 290 /* 291 * if LLDD reports slave not present, don't clutter 292 * console with alloc failure messages 293 */ 294 if (ret == -ENXIO) 295 display_failure_msg = 0; 296 goto out_device_destroy; 297 } 298 } 299 300 return sdev; 301 302 out_device_destroy: 303 __scsi_remove_device(sdev); 304 out: 305 if (display_failure_msg) 306 printk(ALLOC_FAILURE_MSG, __func__); 307 return NULL; 308 } 309 310 static void scsi_target_destroy(struct scsi_target *starget) 311 { 312 struct device *dev = &starget->dev; 313 struct Scsi_Host *shost = dev_to_shost(dev->parent); 314 unsigned long flags; 315 316 starget->state = STARGET_DEL; 317 transport_destroy_device(dev); 318 spin_lock_irqsave(shost->host_lock, flags); 319 if (shost->hostt->target_destroy) 320 shost->hostt->target_destroy(starget); 321 list_del_init(&starget->siblings); 322 spin_unlock_irqrestore(shost->host_lock, flags); 323 put_device(dev); 324 } 325 326 static void scsi_target_dev_release(struct device *dev) 327 { 328 struct device *parent = dev->parent; 329 struct scsi_target *starget = to_scsi_target(dev); 330 331 kfree(starget); 332 put_device(parent); 333 } 334 335 static struct device_type scsi_target_type = { 336 .name = "scsi_target", 337 .release = scsi_target_dev_release, 338 }; 339 340 int scsi_is_target_device(const struct device *dev) 341 { 342 return dev->type == &scsi_target_type; 343 } 344 EXPORT_SYMBOL(scsi_is_target_device); 345 346 static struct scsi_target *__scsi_find_target(struct device *parent, 347 int channel, uint id) 348 { 349 struct scsi_target *starget, *found_starget = NULL; 350 struct Scsi_Host *shost = dev_to_shost(parent); 351 /* 352 * Search for an existing target for this sdev. 353 */ 354 list_for_each_entry(starget, &shost->__targets, siblings) { 355 if (starget->id == id && 356 starget->channel == channel) { 357 found_starget = starget; 358 break; 359 } 360 } 361 if (found_starget) 362 get_device(&found_starget->dev); 363 364 return found_starget; 365 } 366 367 /** 368 * scsi_target_reap_ref_release - remove target from visibility 369 * @kref: the reap_ref in the target being released 370 * 371 * Called on last put of reap_ref, which is the indication that no device 372 * under this target is visible anymore, so render the target invisible in 373 * sysfs. Note: we have to be in user context here because the target reaps 374 * should be done in places where the scsi device visibility is being removed. 375 */ 376 static void scsi_target_reap_ref_release(struct kref *kref) 377 { 378 struct scsi_target *starget 379 = container_of(kref, struct scsi_target, reap_ref); 380 381 /* 382 * if we get here and the target is still in the CREATED state that 383 * means it was allocated but never made visible (because a scan 384 * turned up no LUNs), so don't call device_del() on it. 385 */ 386 if (starget->state != STARGET_CREATED) { 387 transport_remove_device(&starget->dev); 388 device_del(&starget->dev); 389 } 390 scsi_target_destroy(starget); 391 } 392 393 static void scsi_target_reap_ref_put(struct scsi_target *starget) 394 { 395 kref_put(&starget->reap_ref, scsi_target_reap_ref_release); 396 } 397 398 /** 399 * scsi_alloc_target - allocate a new or find an existing target 400 * @parent: parent of the target (need not be a scsi host) 401 * @channel: target channel number (zero if no channels) 402 * @id: target id number 403 * 404 * Return an existing target if one exists, provided it hasn't already 405 * gone into STARGET_DEL state, otherwise allocate a new target. 406 * 407 * The target is returned with an incremented reference, so the caller 408 * is responsible for both reaping and doing a last put 409 */ 410 static struct scsi_target *scsi_alloc_target(struct device *parent, 411 int channel, uint id) 412 { 413 struct Scsi_Host *shost = dev_to_shost(parent); 414 struct device *dev = NULL; 415 unsigned long flags; 416 const int size = sizeof(struct scsi_target) 417 + shost->transportt->target_size; 418 struct scsi_target *starget; 419 struct scsi_target *found_target; 420 int error, ref_got; 421 422 starget = kzalloc(size, GFP_KERNEL); 423 if (!starget) { 424 printk(KERN_ERR "%s: allocation failure\n", __func__); 425 return NULL; 426 } 427 dev = &starget->dev; 428 device_initialize(dev); 429 kref_init(&starget->reap_ref); 430 dev->parent = get_device(parent); 431 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); 432 dev->bus = &scsi_bus_type; 433 dev->type = &scsi_target_type; 434 starget->id = id; 435 starget->channel = channel; 436 starget->can_queue = 0; 437 INIT_LIST_HEAD(&starget->siblings); 438 INIT_LIST_HEAD(&starget->devices); 439 starget->state = STARGET_CREATED; 440 starget->scsi_level = SCSI_2; 441 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; 442 retry: 443 spin_lock_irqsave(shost->host_lock, flags); 444 445 found_target = __scsi_find_target(parent, channel, id); 446 if (found_target) 447 goto found; 448 449 list_add_tail(&starget->siblings, &shost->__targets); 450 spin_unlock_irqrestore(shost->host_lock, flags); 451 /* allocate and add */ 452 transport_setup_device(dev); 453 if (shost->hostt->target_alloc) { 454 error = shost->hostt->target_alloc(starget); 455 456 if(error) { 457 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error); 458 /* don't want scsi_target_reap to do the final 459 * put because it will be under the host lock */ 460 scsi_target_destroy(starget); 461 return NULL; 462 } 463 } 464 get_device(dev); 465 466 return starget; 467 468 found: 469 /* 470 * release routine already fired if kref is zero, so if we can still 471 * take the reference, the target must be alive. If we can't, it must 472 * be dying and we need to wait for a new target 473 */ 474 ref_got = kref_get_unless_zero(&found_target->reap_ref); 475 476 spin_unlock_irqrestore(shost->host_lock, flags); 477 if (ref_got) { 478 put_device(dev); 479 return found_target; 480 } 481 /* 482 * Unfortunately, we found a dying target; need to wait until it's 483 * dead before we can get a new one. There is an anomaly here. We 484 * *should* call scsi_target_reap() to balance the kref_get() of the 485 * reap_ref above. However, since the target being released, it's 486 * already invisible and the reap_ref is irrelevant. If we call 487 * scsi_target_reap() we might spuriously do another device_del() on 488 * an already invisible target. 489 */ 490 put_device(&found_target->dev); 491 /* 492 * length of time is irrelevant here, we just want to yield the CPU 493 * for a tick to avoid busy waiting for the target to die. 494 */ 495 msleep(1); 496 goto retry; 497 } 498 499 /** 500 * scsi_target_reap - check to see if target is in use and destroy if not 501 * @starget: target to be checked 502 * 503 * This is used after removing a LUN or doing a last put of the target 504 * it checks atomically that nothing is using the target and removes 505 * it if so. 506 */ 507 void scsi_target_reap(struct scsi_target *starget) 508 { 509 /* 510 * serious problem if this triggers: STARGET_DEL is only set in the if 511 * the reap_ref drops to zero, so we're trying to do another final put 512 * on an already released kref 513 */ 514 BUG_ON(starget->state == STARGET_DEL); 515 scsi_target_reap_ref_put(starget); 516 } 517 518 /** 519 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string 520 * @s: INQUIRY result string to sanitize 521 * @len: length of the string 522 * 523 * Description: 524 * The SCSI spec says that INQUIRY vendor, product, and revision 525 * strings must consist entirely of graphic ASCII characters, 526 * padded on the right with spaces. Since not all devices obey 527 * this rule, we will replace non-graphic or non-ASCII characters 528 * with spaces. Exception: a NUL character is interpreted as a 529 * string terminator, so all the following characters are set to 530 * spaces. 531 **/ 532 static void sanitize_inquiry_string(unsigned char *s, int len) 533 { 534 int terminated = 0; 535 536 for (; len > 0; (--len, ++s)) { 537 if (*s == 0) 538 terminated = 1; 539 if (terminated || *s < 0x20 || *s > 0x7e) 540 *s = ' '; 541 } 542 } 543 544 /** 545 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY 546 * @sdev: scsi_device to probe 547 * @inq_result: area to store the INQUIRY result 548 * @result_len: len of inq_result 549 * @bflags: store any bflags found here 550 * 551 * Description: 552 * Probe the lun associated with @req using a standard SCSI INQUIRY; 553 * 554 * If the INQUIRY is successful, zero is returned and the 555 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length 556 * are copied to the scsi_device any flags value is stored in *@bflags. 557 **/ 558 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, 559 int result_len, int *bflags) 560 { 561 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 562 int first_inquiry_len, try_inquiry_len, next_inquiry_len; 563 int response_len = 0; 564 int pass, count, result; 565 struct scsi_sense_hdr sshdr; 566 567 *bflags = 0; 568 569 /* Perform up to 3 passes. The first pass uses a conservative 570 * transfer length of 36 unless sdev->inquiry_len specifies a 571 * different value. */ 572 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; 573 try_inquiry_len = first_inquiry_len; 574 pass = 1; 575 576 next_pass: 577 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 578 "scsi scan: INQUIRY pass %d length %d\n", 579 pass, try_inquiry_len)); 580 581 /* Each pass gets up to three chances to ignore Unit Attention */ 582 for (count = 0; count < 3; ++count) { 583 int resid; 584 585 memset(scsi_cmd, 0, 6); 586 scsi_cmd[0] = INQUIRY; 587 scsi_cmd[4] = (unsigned char) try_inquiry_len; 588 589 memset(inq_result, 0, try_inquiry_len); 590 591 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 592 inq_result, try_inquiry_len, &sshdr, 593 HZ / 2 + HZ * scsi_inq_timeout, 3, 594 &resid); 595 596 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 597 "scsi scan: INQUIRY %s with code 0x%x\n", 598 result ? "failed" : "successful", result)); 599 600 if (result) { 601 /* 602 * not-ready to ready transition [asc/ascq=0x28/0x0] 603 * or power-on, reset [asc/ascq=0x29/0x0], continue. 604 * INQUIRY should not yield UNIT_ATTENTION 605 * but many buggy devices do so anyway. 606 */ 607 if ((driver_byte(result) & DRIVER_SENSE) && 608 scsi_sense_valid(&sshdr)) { 609 if ((sshdr.sense_key == UNIT_ATTENTION) && 610 ((sshdr.asc == 0x28) || 611 (sshdr.asc == 0x29)) && 612 (sshdr.ascq == 0)) 613 continue; 614 } 615 } else { 616 /* 617 * if nothing was transferred, we try 618 * again. It's a workaround for some USB 619 * devices. 620 */ 621 if (resid == try_inquiry_len) 622 continue; 623 } 624 break; 625 } 626 627 if (result == 0) { 628 sanitize_inquiry_string(&inq_result[8], 8); 629 sanitize_inquiry_string(&inq_result[16], 16); 630 sanitize_inquiry_string(&inq_result[32], 4); 631 632 response_len = inq_result[4] + 5; 633 if (response_len > 255) 634 response_len = first_inquiry_len; /* sanity */ 635 636 /* 637 * Get any flags for this device. 638 * 639 * XXX add a bflags to scsi_device, and replace the 640 * corresponding bit fields in scsi_device, so bflags 641 * need not be passed as an argument. 642 */ 643 *bflags = scsi_get_device_flags(sdev, &inq_result[8], 644 &inq_result[16]); 645 646 /* When the first pass succeeds we gain information about 647 * what larger transfer lengths might work. */ 648 if (pass == 1) { 649 if (BLIST_INQUIRY_36 & *bflags) 650 next_inquiry_len = 36; 651 else if (BLIST_INQUIRY_58 & *bflags) 652 next_inquiry_len = 58; 653 else if (sdev->inquiry_len) 654 next_inquiry_len = sdev->inquiry_len; 655 else 656 next_inquiry_len = response_len; 657 658 /* If more data is available perform the second pass */ 659 if (next_inquiry_len > try_inquiry_len) { 660 try_inquiry_len = next_inquiry_len; 661 pass = 2; 662 goto next_pass; 663 } 664 } 665 666 } else if (pass == 2) { 667 sdev_printk(KERN_INFO, sdev, 668 "scsi scan: %d byte inquiry failed. " 669 "Consider BLIST_INQUIRY_36 for this device\n", 670 try_inquiry_len); 671 672 /* If this pass failed, the third pass goes back and transfers 673 * the same amount as we successfully got in the first pass. */ 674 try_inquiry_len = first_inquiry_len; 675 pass = 3; 676 goto next_pass; 677 } 678 679 /* If the last transfer attempt got an error, assume the 680 * peripheral doesn't exist or is dead. */ 681 if (result) 682 return -EIO; 683 684 /* Don't report any more data than the device says is valid */ 685 sdev->inquiry_len = min(try_inquiry_len, response_len); 686 687 /* 688 * XXX Abort if the response length is less than 36? If less than 689 * 32, the lookup of the device flags (above) could be invalid, 690 * and it would be possible to take an incorrect action - we do 691 * not want to hang because of a short INQUIRY. On the flip side, 692 * if the device is spun down or becoming ready (and so it gives a 693 * short INQUIRY), an abort here prevents any further use of the 694 * device, including spin up. 695 * 696 * On the whole, the best approach seems to be to assume the first 697 * 36 bytes are valid no matter what the device says. That's 698 * better than copying < 36 bytes to the inquiry-result buffer 699 * and displaying garbage for the Vendor, Product, or Revision 700 * strings. 701 */ 702 if (sdev->inquiry_len < 36) { 703 sdev_printk(KERN_INFO, sdev, 704 "scsi scan: INQUIRY result too short (%d)," 705 " using 36\n", sdev->inquiry_len); 706 sdev->inquiry_len = 36; 707 } 708 709 /* 710 * Related to the above issue: 711 * 712 * XXX Devices (disk or all?) should be sent a TEST UNIT READY, 713 * and if not ready, sent a START_STOP to start (maybe spin up) and 714 * then send the INQUIRY again, since the INQUIRY can change after 715 * a device is initialized. 716 * 717 * Ideally, start a device if explicitly asked to do so. This 718 * assumes that a device is spun up on power on, spun down on 719 * request, and then spun up on request. 720 */ 721 722 /* 723 * The scanning code needs to know the scsi_level, even if no 724 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so 725 * non-zero LUNs can be scanned. 726 */ 727 sdev->scsi_level = inq_result[2] & 0x07; 728 if (sdev->scsi_level >= 2 || 729 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) 730 sdev->scsi_level++; 731 sdev->sdev_target->scsi_level = sdev->scsi_level; 732 733 /* 734 * If SCSI-2 or lower, and if the transport requires it, 735 * store the LUN value in CDB[1]. 736 */ 737 sdev->lun_in_cdb = 0; 738 if (sdev->scsi_level <= SCSI_2 && 739 sdev->scsi_level != SCSI_UNKNOWN && 740 !sdev->host->no_scsi2_lun_in_cdb) 741 sdev->lun_in_cdb = 1; 742 743 return 0; 744 } 745 746 /** 747 * scsi_add_lun - allocate and fully initialze a scsi_device 748 * @sdev: holds information to be stored in the new scsi_device 749 * @inq_result: holds the result of a previous INQUIRY to the LUN 750 * @bflags: black/white list flag 751 * @async: 1 if this device is being scanned asynchronously 752 * 753 * Description: 754 * Initialize the scsi_device @sdev. Optionally set fields based 755 * on values in *@bflags. 756 * 757 * Return: 758 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 759 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 760 **/ 761 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, 762 int *bflags, int async) 763 { 764 int ret; 765 766 /* 767 * XXX do not save the inquiry, since it can change underneath us, 768 * save just vendor/model/rev. 769 * 770 * Rather than save it and have an ioctl that retrieves the saved 771 * value, have an ioctl that executes the same INQUIRY code used 772 * in scsi_probe_lun, let user level programs doing INQUIRY 773 * scanning run at their own risk, or supply a user level program 774 * that can correctly scan. 775 */ 776 777 /* 778 * Copy at least 36 bytes of INQUIRY data, so that we don't 779 * dereference unallocated memory when accessing the Vendor, 780 * Product, and Revision strings. Badly behaved devices may set 781 * the INQUIRY Additional Length byte to a small value, indicating 782 * these strings are invalid, but often they contain plausible data 783 * nonetheless. It doesn't matter if the device sent < 36 bytes 784 * total, since scsi_probe_lun() initializes inq_result with 0s. 785 */ 786 sdev->inquiry = kmemdup(inq_result, 787 max_t(size_t, sdev->inquiry_len, 36), 788 GFP_ATOMIC); 789 if (sdev->inquiry == NULL) 790 return SCSI_SCAN_NO_RESPONSE; 791 792 sdev->vendor = (char *) (sdev->inquiry + 8); 793 sdev->model = (char *) (sdev->inquiry + 16); 794 sdev->rev = (char *) (sdev->inquiry + 32); 795 796 if (strncmp(sdev->vendor, "ATA ", 8) == 0) { 797 /* 798 * sata emulation layer device. This is a hack to work around 799 * the SATL power management specifications which state that 800 * when the SATL detects the device has gone into standby 801 * mode, it shall respond with NOT READY. 802 */ 803 sdev->allow_restart = 1; 804 } 805 806 if (*bflags & BLIST_ISROM) { 807 sdev->type = TYPE_ROM; 808 sdev->removable = 1; 809 } else { 810 sdev->type = (inq_result[0] & 0x1f); 811 sdev->removable = (inq_result[1] & 0x80) >> 7; 812 813 /* 814 * some devices may respond with wrong type for 815 * well-known logical units. Force well-known type 816 * to enumerate them correctly. 817 */ 818 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) { 819 sdev_printk(KERN_WARNING, sdev, 820 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n", 821 __func__, sdev->type, (unsigned int)sdev->lun); 822 sdev->type = TYPE_WLUN; 823 } 824 825 } 826 827 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { 828 /* RBC and MMC devices can return SCSI-3 compliance and yet 829 * still not support REPORT LUNS, so make them act as 830 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is 831 * specifically set */ 832 if ((*bflags & BLIST_REPORTLUN2) == 0) 833 *bflags |= BLIST_NOREPORTLUN; 834 } 835 836 /* 837 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI 838 * spec says: The device server is capable of supporting the 839 * specified peripheral device type on this logical unit. However, 840 * the physical device is not currently connected to this logical 841 * unit. 842 * 843 * The above is vague, as it implies that we could treat 001 and 844 * 011 the same. Stay compatible with previous code, and create a 845 * scsi_device for a PQ of 1 846 * 847 * Don't set the device offline here; rather let the upper 848 * level drivers eval the PQ to decide whether they should 849 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. 850 */ 851 852 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; 853 sdev->lockable = sdev->removable; 854 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); 855 856 if (sdev->scsi_level >= SCSI_3 || 857 (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) 858 sdev->ppr = 1; 859 if (inq_result[7] & 0x60) 860 sdev->wdtr = 1; 861 if (inq_result[7] & 0x10) 862 sdev->sdtr = 1; 863 864 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " 865 "ANSI: %d%s\n", scsi_device_type(sdev->type), 866 sdev->vendor, sdev->model, sdev->rev, 867 sdev->inq_periph_qual, inq_result[2] & 0x07, 868 (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); 869 870 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && 871 !(*bflags & BLIST_NOTQ)) { 872 sdev->tagged_supported = 1; 873 sdev->simple_tags = 1; 874 } 875 876 /* 877 * Some devices (Texel CD ROM drives) have handshaking problems 878 * when used with the Seagate controllers. borken is initialized 879 * to 1, and then set it to 0 here. 880 */ 881 if ((*bflags & BLIST_BORKEN) == 0) 882 sdev->borken = 0; 883 884 if (*bflags & BLIST_NO_ULD_ATTACH) 885 sdev->no_uld_attach = 1; 886 887 /* 888 * Apparently some really broken devices (contrary to the SCSI 889 * standards) need to be selected without asserting ATN 890 */ 891 if (*bflags & BLIST_SELECT_NO_ATN) 892 sdev->select_no_atn = 1; 893 894 /* 895 * Maximum 512 sector transfer length 896 * broken RA4x00 Compaq Disk Array 897 */ 898 if (*bflags & BLIST_MAX_512) 899 blk_queue_max_hw_sectors(sdev->request_queue, 512); 900 901 /* 902 * Some devices may not want to have a start command automatically 903 * issued when a device is added. 904 */ 905 if (*bflags & BLIST_NOSTARTONADD) 906 sdev->no_start_on_add = 1; 907 908 if (*bflags & BLIST_SINGLELUN) 909 scsi_target(sdev)->single_lun = 1; 910 911 sdev->use_10_for_rw = 1; 912 913 if (*bflags & BLIST_MS_SKIP_PAGE_08) 914 sdev->skip_ms_page_8 = 1; 915 916 if (*bflags & BLIST_MS_SKIP_PAGE_3F) 917 sdev->skip_ms_page_3f = 1; 918 919 if (*bflags & BLIST_USE_10_BYTE_MS) 920 sdev->use_10_for_ms = 1; 921 922 /* some devices don't like REPORT SUPPORTED OPERATION CODES 923 * and will simply timeout causing sd_mod init to take a very 924 * very long time */ 925 if (*bflags & BLIST_NO_RSOC) 926 sdev->no_report_opcodes = 1; 927 928 /* set the device running here so that slave configure 929 * may do I/O */ 930 ret = scsi_device_set_state(sdev, SDEV_RUNNING); 931 if (ret) { 932 ret = scsi_device_set_state(sdev, SDEV_BLOCK); 933 934 if (ret) { 935 sdev_printk(KERN_ERR, sdev, 936 "in wrong state %s to complete scan\n", 937 scsi_device_state_name(sdev->sdev_state)); 938 return SCSI_SCAN_NO_RESPONSE; 939 } 940 } 941 942 if (*bflags & BLIST_MS_192_BYTES_FOR_3F) 943 sdev->use_192_bytes_for_3f = 1; 944 945 if (*bflags & BLIST_NOT_LOCKABLE) 946 sdev->lockable = 0; 947 948 if (*bflags & BLIST_RETRY_HWERROR) 949 sdev->retry_hwerror = 1; 950 951 if (*bflags & BLIST_NO_DIF) 952 sdev->no_dif = 1; 953 954 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; 955 956 if (*bflags & BLIST_TRY_VPD_PAGES) 957 sdev->try_vpd_pages = 1; 958 else if (*bflags & BLIST_SKIP_VPD_PAGES) 959 sdev->skip_vpd_pages = 1; 960 961 transport_configure_device(&sdev->sdev_gendev); 962 963 if (sdev->host->hostt->slave_configure) { 964 ret = sdev->host->hostt->slave_configure(sdev); 965 if (ret) { 966 /* 967 * if LLDD reports slave not present, don't clutter 968 * console with alloc failure messages 969 */ 970 if (ret != -ENXIO) { 971 sdev_printk(KERN_ERR, sdev, 972 "failed to configure device\n"); 973 } 974 return SCSI_SCAN_NO_RESPONSE; 975 } 976 } 977 978 if (sdev->scsi_level >= SCSI_3) 979 scsi_attach_vpd(sdev); 980 981 sdev->max_queue_depth = sdev->queue_depth; 982 983 /* 984 * Ok, the device is now all set up, we can 985 * register it and tell the rest of the kernel 986 * about it. 987 */ 988 if (!async && scsi_sysfs_add_sdev(sdev) != 0) 989 return SCSI_SCAN_NO_RESPONSE; 990 991 return SCSI_SCAN_LUN_PRESENT; 992 } 993 994 #ifdef CONFIG_SCSI_LOGGING 995 /** 996 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace 997 * @buf: Output buffer with at least end-first+1 bytes of space 998 * @inq: Inquiry buffer (input) 999 * @first: Offset of string into inq 1000 * @end: Index after last character in inq 1001 */ 1002 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, 1003 unsigned first, unsigned end) 1004 { 1005 unsigned term = 0, idx; 1006 1007 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { 1008 if (inq[idx+first] > ' ') { 1009 buf[idx] = inq[idx+first]; 1010 term = idx+1; 1011 } else { 1012 buf[idx] = ' '; 1013 } 1014 } 1015 buf[term] = 0; 1016 return buf; 1017 } 1018 #endif 1019 1020 /** 1021 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it 1022 * @starget: pointer to target device structure 1023 * @lun: LUN of target device 1024 * @bflagsp: store bflags here if not NULL 1025 * @sdevp: probe the LUN corresponding to this scsi_device 1026 * @rescan: if nonzero skip some code only needed on first scan 1027 * @hostdata: passed to scsi_alloc_sdev() 1028 * 1029 * Description: 1030 * Call scsi_probe_lun, if a LUN with an attached device is found, 1031 * allocate and set it up by calling scsi_add_lun. 1032 * 1033 * Return: 1034 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 1035 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is 1036 * attached at the LUN 1037 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 1038 **/ 1039 static int scsi_probe_and_add_lun(struct scsi_target *starget, 1040 u64 lun, int *bflagsp, 1041 struct scsi_device **sdevp, int rescan, 1042 void *hostdata) 1043 { 1044 struct scsi_device *sdev; 1045 unsigned char *result; 1046 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256; 1047 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1048 1049 /* 1050 * The rescan flag is used as an optimization, the first scan of a 1051 * host adapter calls into here with rescan == 0. 1052 */ 1053 sdev = scsi_device_lookup_by_target(starget, lun); 1054 if (sdev) { 1055 if (rescan || !scsi_device_created(sdev)) { 1056 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1057 "scsi scan: device exists on %s\n", 1058 dev_name(&sdev->sdev_gendev))); 1059 if (sdevp) 1060 *sdevp = sdev; 1061 else 1062 scsi_device_put(sdev); 1063 1064 if (bflagsp) 1065 *bflagsp = scsi_get_device_flags(sdev, 1066 sdev->vendor, 1067 sdev->model); 1068 return SCSI_SCAN_LUN_PRESENT; 1069 } 1070 scsi_device_put(sdev); 1071 } else 1072 sdev = scsi_alloc_sdev(starget, lun, hostdata); 1073 if (!sdev) 1074 goto out; 1075 1076 result = kmalloc(result_len, GFP_ATOMIC | 1077 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0)); 1078 if (!result) 1079 goto out_free_sdev; 1080 1081 if (scsi_probe_lun(sdev, result, result_len, &bflags)) 1082 goto out_free_result; 1083 1084 if (bflagsp) 1085 *bflagsp = bflags; 1086 /* 1087 * result contains valid SCSI INQUIRY data. 1088 */ 1089 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) { 1090 /* 1091 * For a Peripheral qualifier 3 (011b), the SCSI 1092 * spec says: The device server is not capable of 1093 * supporting a physical device on this logical 1094 * unit. 1095 * 1096 * For disks, this implies that there is no 1097 * logical disk configured at sdev->lun, but there 1098 * is a target id responding. 1099 */ 1100 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" 1101 " peripheral qualifier of 3, device not" 1102 " added\n")) 1103 if (lun == 0) { 1104 SCSI_LOG_SCAN_BUS(1, { 1105 unsigned char vend[9]; 1106 unsigned char mod[17]; 1107 1108 sdev_printk(KERN_INFO, sdev, 1109 "scsi scan: consider passing scsi_mod." 1110 "dev_flags=%s:%s:0x240 or 0x1000240\n", 1111 scsi_inq_str(vend, result, 8, 16), 1112 scsi_inq_str(mod, result, 16, 32)); 1113 }); 1114 1115 } 1116 1117 res = SCSI_SCAN_TARGET_PRESENT; 1118 goto out_free_result; 1119 } 1120 1121 /* 1122 * Some targets may set slight variations of PQ and PDT to signal 1123 * that no LUN is present, so don't add sdev in these cases. 1124 * Two specific examples are: 1125 * 1) NetApp targets: return PQ=1, PDT=0x1f 1126 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" 1127 * in the UFI 1.0 spec (we cannot rely on reserved bits). 1128 * 1129 * References: 1130 * 1) SCSI SPC-3, pp. 145-146 1131 * PQ=1: "A peripheral device having the specified peripheral 1132 * device type is not connected to this logical unit. However, the 1133 * device server is capable of supporting the specified peripheral 1134 * device type on this logical unit." 1135 * PDT=0x1f: "Unknown or no device type" 1136 * 2) USB UFI 1.0, p. 20 1137 * PDT=00h Direct-access device (floppy) 1138 * PDT=1Fh none (no FDD connected to the requested logical unit) 1139 */ 1140 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) && 1141 (result[0] & 0x1f) == 0x1f && 1142 !scsi_is_wlun(lun)) { 1143 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1144 "scsi scan: peripheral device type" 1145 " of 31, no device added\n")); 1146 res = SCSI_SCAN_TARGET_PRESENT; 1147 goto out_free_result; 1148 } 1149 1150 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); 1151 if (res == SCSI_SCAN_LUN_PRESENT) { 1152 if (bflags & BLIST_KEY) { 1153 sdev->lockable = 0; 1154 scsi_unlock_floptical(sdev, result); 1155 } 1156 } 1157 1158 out_free_result: 1159 kfree(result); 1160 out_free_sdev: 1161 if (res == SCSI_SCAN_LUN_PRESENT) { 1162 if (sdevp) { 1163 if (scsi_device_get(sdev) == 0) { 1164 *sdevp = sdev; 1165 } else { 1166 __scsi_remove_device(sdev); 1167 res = SCSI_SCAN_NO_RESPONSE; 1168 } 1169 } 1170 } else 1171 __scsi_remove_device(sdev); 1172 out: 1173 return res; 1174 } 1175 1176 /** 1177 * scsi_sequential_lun_scan - sequentially scan a SCSI target 1178 * @starget: pointer to target structure to scan 1179 * @bflags: black/white list flag for LUN 0 1180 * @scsi_level: Which version of the standard does this device adhere to 1181 * @rescan: passed to scsi_probe_add_lun() 1182 * 1183 * Description: 1184 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been 1185 * scanned) to some maximum lun until a LUN is found with no device 1186 * attached. Use the bflags to figure out any oddities. 1187 * 1188 * Modifies sdevscan->lun. 1189 **/ 1190 static void scsi_sequential_lun_scan(struct scsi_target *starget, 1191 int bflags, int scsi_level, int rescan) 1192 { 1193 uint max_dev_lun; 1194 u64 sparse_lun, lun; 1195 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1196 1197 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget, 1198 "scsi scan: Sequential scan\n")); 1199 1200 max_dev_lun = min(max_scsi_luns, shost->max_lun); 1201 /* 1202 * If this device is known to support sparse multiple units, 1203 * override the other settings, and scan all of them. Normally, 1204 * SCSI-3 devices should be scanned via the REPORT LUNS. 1205 */ 1206 if (bflags & BLIST_SPARSELUN) { 1207 max_dev_lun = shost->max_lun; 1208 sparse_lun = 1; 1209 } else 1210 sparse_lun = 0; 1211 1212 /* 1213 * If less than SCSI_1_CCS, and no special lun scanning, stop 1214 * scanning; this matches 2.4 behaviour, but could just be a bug 1215 * (to continue scanning a SCSI_1_CCS device). 1216 * 1217 * This test is broken. We might not have any device on lun0 for 1218 * a sparselun device, and if that's the case then how would we 1219 * know the real scsi_level, eh? It might make sense to just not 1220 * scan any SCSI_1 device for non-0 luns, but that check would best 1221 * go into scsi_alloc_sdev() and just have it return null when asked 1222 * to alloc an sdev for lun > 0 on an already found SCSI_1 device. 1223 * 1224 if ((sdevscan->scsi_level < SCSI_1_CCS) && 1225 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) 1226 == 0)) 1227 return; 1228 */ 1229 /* 1230 * If this device is known to support multiple units, override 1231 * the other settings, and scan all of them. 1232 */ 1233 if (bflags & BLIST_FORCELUN) 1234 max_dev_lun = shost->max_lun; 1235 /* 1236 * REGAL CDC-4X: avoid hang after LUN 4 1237 */ 1238 if (bflags & BLIST_MAX5LUN) 1239 max_dev_lun = min(5U, max_dev_lun); 1240 /* 1241 * Do not scan SCSI-2 or lower device past LUN 7, unless 1242 * BLIST_LARGELUN. 1243 */ 1244 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) 1245 max_dev_lun = min(8U, max_dev_lun); 1246 1247 /* 1248 * Stop scanning at 255 unless BLIST_SCSI3LUN 1249 */ 1250 if (!(bflags & BLIST_SCSI3LUN)) 1251 max_dev_lun = min(256U, max_dev_lun); 1252 1253 /* 1254 * We have already scanned LUN 0, so start at LUN 1. Keep scanning 1255 * until we reach the max, or no LUN is found and we are not 1256 * sparse_lun. 1257 */ 1258 for (lun = 1; lun < max_dev_lun; ++lun) 1259 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, 1260 NULL) != SCSI_SCAN_LUN_PRESENT) && 1261 !sparse_lun) 1262 return; 1263 } 1264 1265 /** 1266 * scsilun_to_int - convert a scsi_lun to an int 1267 * @scsilun: struct scsi_lun to be converted. 1268 * 1269 * Description: 1270 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered 1271 * integer, and return the result. The caller must check for 1272 * truncation before using this function. 1273 * 1274 * Notes: 1275 * For a description of the LUN format, post SCSI-3 see the SCSI 1276 * Architecture Model, for SCSI-3 see the SCSI Controller Commands. 1277 * 1278 * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function 1279 * returns the integer: 0x0b03d204 1280 * 1281 * This encoding will return a standard integer LUN for LUNs smaller 1282 * than 256, which typically use a single level LUN structure with 1283 * addressing method 0. 1284 **/ 1285 u64 scsilun_to_int(struct scsi_lun *scsilun) 1286 { 1287 int i; 1288 u64 lun; 1289 1290 lun = 0; 1291 for (i = 0; i < sizeof(lun); i += 2) 1292 lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) | 1293 ((u64)scsilun->scsi_lun[i + 1] << (i * 8))); 1294 return lun; 1295 } 1296 EXPORT_SYMBOL(scsilun_to_int); 1297 1298 /** 1299 * int_to_scsilun - reverts an int into a scsi_lun 1300 * @lun: integer to be reverted 1301 * @scsilun: struct scsi_lun to be set. 1302 * 1303 * Description: 1304 * Reverts the functionality of the scsilun_to_int, which packed 1305 * an 8-byte lun value into an int. This routine unpacks the int 1306 * back into the lun value. 1307 * 1308 * Notes: 1309 * Given an integer : 0x0b03d204, this function returns a 1310 * struct scsi_lun of: d2 04 0b 03 00 00 00 00 1311 * 1312 **/ 1313 void int_to_scsilun(u64 lun, struct scsi_lun *scsilun) 1314 { 1315 int i; 1316 1317 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun)); 1318 1319 for (i = 0; i < sizeof(lun); i += 2) { 1320 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF; 1321 scsilun->scsi_lun[i+1] = lun & 0xFF; 1322 lun = lun >> 16; 1323 } 1324 } 1325 EXPORT_SYMBOL(int_to_scsilun); 1326 1327 /** 1328 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results 1329 * @starget: which target 1330 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN 1331 * @rescan: nonzero if we can skip code only needed on first scan 1332 * 1333 * Description: 1334 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. 1335 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. 1336 * 1337 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 1338 * LUNs even if it's older than SCSI-3. 1339 * If BLIST_NOREPORTLUN is set, return 1 always. 1340 * If BLIST_NOLUN is set, return 0 always. 1341 * If starget->no_report_luns is set, return 1 always. 1342 * 1343 * Return: 1344 * 0: scan completed (or no memory, so further scanning is futile) 1345 * 1: could not scan with REPORT LUN 1346 **/ 1347 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags, 1348 int rescan) 1349 { 1350 char devname[64]; 1351 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 1352 unsigned int length; 1353 u64 lun; 1354 unsigned int num_luns; 1355 unsigned int retries; 1356 int result; 1357 struct scsi_lun *lunp, *lun_data; 1358 struct scsi_sense_hdr sshdr; 1359 struct scsi_device *sdev; 1360 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 1361 int ret = 0; 1362 1363 /* 1364 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. 1365 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does 1366 * support more than 8 LUNs. 1367 * Don't attempt if the target doesn't support REPORT LUNS. 1368 */ 1369 if (bflags & BLIST_NOREPORTLUN) 1370 return 1; 1371 if (starget->scsi_level < SCSI_2 && 1372 starget->scsi_level != SCSI_UNKNOWN) 1373 return 1; 1374 if (starget->scsi_level < SCSI_3 && 1375 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) 1376 return 1; 1377 if (bflags & BLIST_NOLUN) 1378 return 0; 1379 if (starget->no_report_luns) 1380 return 1; 1381 1382 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { 1383 sdev = scsi_alloc_sdev(starget, 0, NULL); 1384 if (!sdev) 1385 return 0; 1386 if (scsi_device_get(sdev)) { 1387 __scsi_remove_device(sdev); 1388 return 0; 1389 } 1390 } 1391 1392 sprintf(devname, "host %d channel %d id %d", 1393 shost->host_no, sdev->channel, sdev->id); 1394 1395 /* 1396 * Allocate enough to hold the header (the same size as one scsi_lun) 1397 * plus the number of luns we are requesting. 511 was the default 1398 * value of the now removed max_report_luns parameter. 1399 */ 1400 length = (511 + 1) * sizeof(struct scsi_lun); 1401 retry: 1402 lun_data = kmalloc(length, GFP_KERNEL | 1403 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0)); 1404 if (!lun_data) { 1405 printk(ALLOC_FAILURE_MSG, __func__); 1406 goto out; 1407 } 1408 1409 scsi_cmd[0] = REPORT_LUNS; 1410 1411 /* 1412 * bytes 1 - 5: reserved, set to zero. 1413 */ 1414 memset(&scsi_cmd[1], 0, 5); 1415 1416 /* 1417 * bytes 6 - 9: length of the command. 1418 */ 1419 put_unaligned_be32(length, &scsi_cmd[6]); 1420 1421 scsi_cmd[10] = 0; /* reserved */ 1422 scsi_cmd[11] = 0; /* control */ 1423 1424 /* 1425 * We can get a UNIT ATTENTION, for example a power on/reset, so 1426 * retry a few times (like sd.c does for TEST UNIT READY). 1427 * Experience shows some combinations of adapter/devices get at 1428 * least two power on/resets. 1429 * 1430 * Illegal requests (for devices that do not support REPORT LUNS) 1431 * should come through as a check condition, and will not generate 1432 * a retry. 1433 */ 1434 for (retries = 0; retries < 3; retries++) { 1435 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1436 "scsi scan: Sending REPORT LUNS to (try %d)\n", 1437 retries)); 1438 1439 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 1440 lun_data, length, &sshdr, 1441 SCSI_TIMEOUT + 4 * HZ, 3, NULL); 1442 1443 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1444 "scsi scan: REPORT LUNS" 1445 " %s (try %d) result 0x%x\n", 1446 result ? "failed" : "successful", 1447 retries, result)); 1448 if (result == 0) 1449 break; 1450 else if (scsi_sense_valid(&sshdr)) { 1451 if (sshdr.sense_key != UNIT_ATTENTION) 1452 break; 1453 } 1454 } 1455 1456 if (result) { 1457 /* 1458 * The device probably does not support a REPORT LUN command 1459 */ 1460 ret = 1; 1461 goto out_err; 1462 } 1463 1464 /* 1465 * Get the length from the first four bytes of lun_data. 1466 */ 1467 if (get_unaligned_be32(lun_data->scsi_lun) + 1468 sizeof(struct scsi_lun) > length) { 1469 length = get_unaligned_be32(lun_data->scsi_lun) + 1470 sizeof(struct scsi_lun); 1471 kfree(lun_data); 1472 goto retry; 1473 } 1474 length = get_unaligned_be32(lun_data->scsi_lun); 1475 1476 num_luns = (length / sizeof(struct scsi_lun)); 1477 1478 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1479 "scsi scan: REPORT LUN scan\n")); 1480 1481 /* 1482 * Scan the luns in lun_data. The entry at offset 0 is really 1483 * the header, so start at 1 and go up to and including num_luns. 1484 */ 1485 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { 1486 lun = scsilun_to_int(lunp); 1487 1488 if (lun > sdev->host->max_lun) { 1489 sdev_printk(KERN_WARNING, sdev, 1490 "lun%llu has a LUN larger than" 1491 " allowed by the host adapter\n", lun); 1492 } else { 1493 int res; 1494 1495 res = scsi_probe_and_add_lun(starget, 1496 lun, NULL, NULL, rescan, NULL); 1497 if (res == SCSI_SCAN_NO_RESPONSE) { 1498 /* 1499 * Got some results, but now none, abort. 1500 */ 1501 sdev_printk(KERN_ERR, sdev, 1502 "Unexpected response" 1503 " from lun %llu while scanning, scan" 1504 " aborted\n", (unsigned long long)lun); 1505 break; 1506 } 1507 } 1508 } 1509 1510 out_err: 1511 kfree(lun_data); 1512 out: 1513 scsi_device_put(sdev); 1514 if (scsi_device_created(sdev)) 1515 /* 1516 * the sdev we used didn't appear in the report luns scan 1517 */ 1518 __scsi_remove_device(sdev); 1519 return ret; 1520 } 1521 1522 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, 1523 uint id, u64 lun, void *hostdata) 1524 { 1525 struct scsi_device *sdev = ERR_PTR(-ENODEV); 1526 struct device *parent = &shost->shost_gendev; 1527 struct scsi_target *starget; 1528 1529 if (strncmp(scsi_scan_type, "none", 4) == 0) 1530 return ERR_PTR(-ENODEV); 1531 1532 starget = scsi_alloc_target(parent, channel, id); 1533 if (!starget) 1534 return ERR_PTR(-ENOMEM); 1535 scsi_autopm_get_target(starget); 1536 1537 mutex_lock(&shost->scan_mutex); 1538 if (!shost->async_scan) 1539 scsi_complete_async_scans(); 1540 1541 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1542 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); 1543 scsi_autopm_put_host(shost); 1544 } 1545 mutex_unlock(&shost->scan_mutex); 1546 scsi_autopm_put_target(starget); 1547 /* 1548 * paired with scsi_alloc_target(). Target will be destroyed unless 1549 * scsi_probe_and_add_lun made an underlying device visible 1550 */ 1551 scsi_target_reap(starget); 1552 put_device(&starget->dev); 1553 1554 return sdev; 1555 } 1556 EXPORT_SYMBOL(__scsi_add_device); 1557 1558 int scsi_add_device(struct Scsi_Host *host, uint channel, 1559 uint target, u64 lun) 1560 { 1561 struct scsi_device *sdev = 1562 __scsi_add_device(host, channel, target, lun, NULL); 1563 if (IS_ERR(sdev)) 1564 return PTR_ERR(sdev); 1565 1566 scsi_device_put(sdev); 1567 return 0; 1568 } 1569 EXPORT_SYMBOL(scsi_add_device); 1570 1571 void scsi_rescan_device(struct device *dev) 1572 { 1573 if (!dev->driver) 1574 return; 1575 1576 if (try_module_get(dev->driver->owner)) { 1577 struct scsi_driver *drv = to_scsi_driver(dev->driver); 1578 1579 if (drv->rescan) 1580 drv->rescan(dev); 1581 module_put(dev->driver->owner); 1582 } 1583 } 1584 EXPORT_SYMBOL(scsi_rescan_device); 1585 1586 static void __scsi_scan_target(struct device *parent, unsigned int channel, 1587 unsigned int id, u64 lun, int rescan) 1588 { 1589 struct Scsi_Host *shost = dev_to_shost(parent); 1590 int bflags = 0; 1591 int res; 1592 struct scsi_target *starget; 1593 1594 if (shost->this_id == id) 1595 /* 1596 * Don't scan the host adapter 1597 */ 1598 return; 1599 1600 starget = scsi_alloc_target(parent, channel, id); 1601 if (!starget) 1602 return; 1603 scsi_autopm_get_target(starget); 1604 1605 if (lun != SCAN_WILD_CARD) { 1606 /* 1607 * Scan for a specific host/chan/id/lun. 1608 */ 1609 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); 1610 goto out_reap; 1611 } 1612 1613 /* 1614 * Scan LUN 0, if there is some response, scan further. Ideally, we 1615 * would not configure LUN 0 until all LUNs are scanned. 1616 */ 1617 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); 1618 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { 1619 if (scsi_report_lun_scan(starget, bflags, rescan) != 0) 1620 /* 1621 * The REPORT LUN did not scan the target, 1622 * do a sequential scan. 1623 */ 1624 scsi_sequential_lun_scan(starget, bflags, 1625 starget->scsi_level, rescan); 1626 } 1627 1628 out_reap: 1629 scsi_autopm_put_target(starget); 1630 /* 1631 * paired with scsi_alloc_target(): determine if the target has 1632 * any children at all and if not, nuke it 1633 */ 1634 scsi_target_reap(starget); 1635 1636 put_device(&starget->dev); 1637 } 1638 1639 /** 1640 * scsi_scan_target - scan a target id, possibly including all LUNs on the target. 1641 * @parent: host to scan 1642 * @channel: channel to scan 1643 * @id: target id to scan 1644 * @lun: Specific LUN to scan or SCAN_WILD_CARD 1645 * @rescan: passed to LUN scanning routines 1646 * 1647 * Description: 1648 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, 1649 * and possibly all LUNs on the target id. 1650 * 1651 * First try a REPORT LUN scan, if that does not scan the target, do a 1652 * sequential scan of LUNs on the target id. 1653 **/ 1654 void scsi_scan_target(struct device *parent, unsigned int channel, 1655 unsigned int id, u64 lun, int rescan) 1656 { 1657 struct Scsi_Host *shost = dev_to_shost(parent); 1658 1659 if (strncmp(scsi_scan_type, "none", 4) == 0) 1660 return; 1661 1662 mutex_lock(&shost->scan_mutex); 1663 if (!shost->async_scan) 1664 scsi_complete_async_scans(); 1665 1666 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1667 __scsi_scan_target(parent, channel, id, lun, rescan); 1668 scsi_autopm_put_host(shost); 1669 } 1670 mutex_unlock(&shost->scan_mutex); 1671 } 1672 EXPORT_SYMBOL(scsi_scan_target); 1673 1674 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, 1675 unsigned int id, u64 lun, int rescan) 1676 { 1677 uint order_id; 1678 1679 if (id == SCAN_WILD_CARD) 1680 for (id = 0; id < shost->max_id; ++id) { 1681 /* 1682 * XXX adapter drivers when possible (FCP, iSCSI) 1683 * could modify max_id to match the current max, 1684 * not the absolute max. 1685 * 1686 * XXX add a shost id iterator, so for example, 1687 * the FC ID can be the same as a target id 1688 * without a huge overhead of sparse id's. 1689 */ 1690 if (shost->reverse_ordering) 1691 /* 1692 * Scan from high to low id. 1693 */ 1694 order_id = shost->max_id - id - 1; 1695 else 1696 order_id = id; 1697 __scsi_scan_target(&shost->shost_gendev, channel, 1698 order_id, lun, rescan); 1699 } 1700 else 1701 __scsi_scan_target(&shost->shost_gendev, channel, 1702 id, lun, rescan); 1703 } 1704 1705 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, 1706 unsigned int id, u64 lun, int rescan) 1707 { 1708 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, 1709 "%s: <%u:%u:%llu>\n", 1710 __func__, channel, id, lun)); 1711 1712 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || 1713 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || 1714 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun))) 1715 return -EINVAL; 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 if (channel == SCAN_WILD_CARD) 1723 for (channel = 0; channel <= shost->max_channel; 1724 channel++) 1725 scsi_scan_channel(shost, channel, id, lun, 1726 rescan); 1727 else 1728 scsi_scan_channel(shost, channel, id, lun, rescan); 1729 scsi_autopm_put_host(shost); 1730 } 1731 mutex_unlock(&shost->scan_mutex); 1732 1733 return 0; 1734 } 1735 1736 static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 1737 { 1738 struct scsi_device *sdev; 1739 shost_for_each_device(sdev, shost) { 1740 /* target removed before the device could be added */ 1741 if (sdev->sdev_state == SDEV_DEL) 1742 continue; 1743 /* If device is already visible, skip adding it to sysfs */ 1744 if (sdev->is_visible) 1745 continue; 1746 if (!scsi_host_scan_allowed(shost) || 1747 scsi_sysfs_add_sdev(sdev) != 0) 1748 __scsi_remove_device(sdev); 1749 } 1750 } 1751 1752 /** 1753 * scsi_prep_async_scan - prepare for an async scan 1754 * @shost: the host which will be scanned 1755 * Returns: a cookie to be passed to scsi_finish_async_scan() 1756 * 1757 * Tells the midlayer this host is going to do an asynchronous scan. 1758 * It reserves the host's position in the scanning list and ensures 1759 * that other asynchronous scans started after this one won't affect the 1760 * ordering of the discovered devices. 1761 */ 1762 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 1763 { 1764 struct async_scan_data *data; 1765 unsigned long flags; 1766 1767 if (strncmp(scsi_scan_type, "sync", 4) == 0) 1768 return NULL; 1769 1770 if (shost->async_scan) { 1771 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1772 dump_stack(); 1773 return NULL; 1774 } 1775 1776 data = kmalloc(sizeof(*data), GFP_KERNEL); 1777 if (!data) 1778 goto err; 1779 data->shost = scsi_host_get(shost); 1780 if (!data->shost) 1781 goto err; 1782 init_completion(&data->prev_finished); 1783 1784 mutex_lock(&shost->scan_mutex); 1785 spin_lock_irqsave(shost->host_lock, flags); 1786 shost->async_scan = 1; 1787 spin_unlock_irqrestore(shost->host_lock, flags); 1788 mutex_unlock(&shost->scan_mutex); 1789 1790 spin_lock(&async_scan_lock); 1791 if (list_empty(&scanning_hosts)) 1792 complete(&data->prev_finished); 1793 list_add_tail(&data->list, &scanning_hosts); 1794 spin_unlock(&async_scan_lock); 1795 1796 return data; 1797 1798 err: 1799 kfree(data); 1800 return NULL; 1801 } 1802 1803 /** 1804 * scsi_finish_async_scan - asynchronous scan has finished 1805 * @data: cookie returned from earlier call to scsi_prep_async_scan() 1806 * 1807 * All the devices currently attached to this host have been found. 1808 * This function announces all the devices it has found to the rest 1809 * of the system. 1810 */ 1811 static void scsi_finish_async_scan(struct async_scan_data *data) 1812 { 1813 struct Scsi_Host *shost; 1814 unsigned long flags; 1815 1816 if (!data) 1817 return; 1818 1819 shost = data->shost; 1820 1821 mutex_lock(&shost->scan_mutex); 1822 1823 if (!shost->async_scan) { 1824 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1825 dump_stack(); 1826 mutex_unlock(&shost->scan_mutex); 1827 return; 1828 } 1829 1830 wait_for_completion(&data->prev_finished); 1831 1832 scsi_sysfs_add_devices(shost); 1833 1834 spin_lock_irqsave(shost->host_lock, flags); 1835 shost->async_scan = 0; 1836 spin_unlock_irqrestore(shost->host_lock, flags); 1837 1838 mutex_unlock(&shost->scan_mutex); 1839 1840 spin_lock(&async_scan_lock); 1841 list_del(&data->list); 1842 if (!list_empty(&scanning_hosts)) { 1843 struct async_scan_data *next = list_entry(scanning_hosts.next, 1844 struct async_scan_data, list); 1845 complete(&next->prev_finished); 1846 } 1847 spin_unlock(&async_scan_lock); 1848 1849 scsi_autopm_put_host(shost); 1850 scsi_host_put(shost); 1851 kfree(data); 1852 } 1853 1854 static void do_scsi_scan_host(struct Scsi_Host *shost) 1855 { 1856 if (shost->hostt->scan_finished) { 1857 unsigned long start = jiffies; 1858 if (shost->hostt->scan_start) 1859 shost->hostt->scan_start(shost); 1860 1861 while (!shost->hostt->scan_finished(shost, jiffies - start)) 1862 msleep(10); 1863 } else { 1864 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, 1865 SCAN_WILD_CARD, 0); 1866 } 1867 } 1868 1869 static void do_scan_async(void *_data, async_cookie_t c) 1870 { 1871 struct async_scan_data *data = _data; 1872 struct Scsi_Host *shost = data->shost; 1873 1874 do_scsi_scan_host(shost); 1875 scsi_finish_async_scan(data); 1876 } 1877 1878 /** 1879 * scsi_scan_host - scan the given adapter 1880 * @shost: adapter to scan 1881 **/ 1882 void scsi_scan_host(struct Scsi_Host *shost) 1883 { 1884 struct async_scan_data *data; 1885 1886 if (strncmp(scsi_scan_type, "none", 4) == 0) 1887 return; 1888 if (scsi_autopm_get_host(shost) < 0) 1889 return; 1890 1891 data = scsi_prep_async_scan(shost); 1892 if (!data) { 1893 do_scsi_scan_host(shost); 1894 scsi_autopm_put_host(shost); 1895 return; 1896 } 1897 1898 /* register with the async subsystem so wait_for_device_probe() 1899 * will flush this work 1900 */ 1901 async_schedule(do_scan_async, data); 1902 1903 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */ 1904 } 1905 EXPORT_SYMBOL(scsi_scan_host); 1906 1907 void scsi_forget_host(struct Scsi_Host *shost) 1908 { 1909 struct scsi_device *sdev; 1910 unsigned long flags; 1911 1912 restart: 1913 spin_lock_irqsave(shost->host_lock, flags); 1914 list_for_each_entry(sdev, &shost->__devices, siblings) { 1915 if (sdev->sdev_state == SDEV_DEL) 1916 continue; 1917 spin_unlock_irqrestore(shost->host_lock, flags); 1918 __scsi_remove_device(sdev); 1919 goto restart; 1920 } 1921 spin_unlock_irqrestore(shost->host_lock, flags); 1922 } 1923 1924 /** 1925 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself 1926 * @shost: Host that needs a scsi_device 1927 * 1928 * Lock status: None assumed. 1929 * 1930 * Returns: The scsi_device or NULL 1931 * 1932 * Notes: 1933 * Attach a single scsi_device to the Scsi_Host - this should 1934 * be made to look like a "pseudo-device" that points to the 1935 * HA itself. 1936 * 1937 * Note - this device is not accessible from any high-level 1938 * drivers (including generics), which is probably not 1939 * optimal. We can add hooks later to attach. 1940 */ 1941 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) 1942 { 1943 struct scsi_device *sdev = NULL; 1944 struct scsi_target *starget; 1945 1946 mutex_lock(&shost->scan_mutex); 1947 if (!scsi_host_scan_allowed(shost)) 1948 goto out; 1949 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); 1950 if (!starget) 1951 goto out; 1952 1953 sdev = scsi_alloc_sdev(starget, 0, NULL); 1954 if (sdev) 1955 sdev->borken = 0; 1956 else 1957 scsi_target_reap(starget); 1958 put_device(&starget->dev); 1959 out: 1960 mutex_unlock(&shost->scan_mutex); 1961 return sdev; 1962 } 1963 EXPORT_SYMBOL(scsi_get_host_dev); 1964 1965 /** 1966 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself 1967 * @sdev: Host device to be freed 1968 * 1969 * Lock status: None assumed. 1970 * 1971 * Returns: Nothing 1972 */ 1973 void scsi_free_host_dev(struct scsi_device *sdev) 1974 { 1975 BUG_ON(sdev->id != sdev->host->this_id); 1976 1977 __scsi_remove_device(sdev); 1978 } 1979 EXPORT_SYMBOL(scsi_free_host_dev); 1980 1981