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 38 #include <scsi/scsi.h> 39 #include <scsi/scsi_cmnd.h> 40 #include <scsi/scsi_device.h> 41 #include <scsi/scsi_driver.h> 42 #include <scsi/scsi_devinfo.h> 43 #include <scsi/scsi_host.h> 44 #include <scsi/scsi_transport.h> 45 #include <scsi/scsi_eh.h> 46 47 #include "scsi_priv.h" 48 #include "scsi_logging.h" 49 50 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \ 51 " SCSI scanning, some SCSI devices might not be configured\n" 52 53 /* 54 * Default timeout 55 */ 56 #define SCSI_TIMEOUT (2*HZ) 57 58 /* 59 * Prefix values for the SCSI id's (stored in sysfs name field) 60 */ 61 #define SCSI_UID_SER_NUM 'S' 62 #define SCSI_UID_UNKNOWN 'Z' 63 64 /* 65 * Return values of some of the scanning functions. 66 * 67 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this 68 * includes allocation or general failures preventing IO from being sent. 69 * 70 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available 71 * on the given LUN. 72 * 73 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a 74 * given LUN. 75 */ 76 #define SCSI_SCAN_NO_RESPONSE 0 77 #define SCSI_SCAN_TARGET_PRESENT 1 78 #define SCSI_SCAN_LUN_PRESENT 2 79 80 static const char *scsi_null_device_strs = "nullnullnullnull"; 81 82 #define MAX_SCSI_LUNS 512 83 84 static u64 max_scsi_luns = MAX_SCSI_LUNS; 85 86 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR); 87 MODULE_PARM_DESC(max_luns, 88 "last scsi LUN (should be between 1 and 2^64-1)"); 89 90 #ifdef CONFIG_SCSI_SCAN_ASYNC 91 #define SCSI_SCAN_TYPE_DEFAULT "async" 92 #else 93 #define SCSI_SCAN_TYPE_DEFAULT "sync" 94 #endif 95 96 char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT; 97 98 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO); 99 MODULE_PARM_DESC(scan, "sync, async or none"); 100 101 /* 102 * max_scsi_report_luns: the maximum number of LUNS that will be 103 * returned from the REPORT LUNS command. 8 times this value must 104 * be allocated. In theory this could be up to an 8 byte value, but 105 * in practice, the maximum number of LUNs suppored by any device 106 * is about 16k. 107 */ 108 static unsigned int max_scsi_report_luns = 511; 109 110 module_param_named(max_report_luns, max_scsi_report_luns, uint, S_IRUGO|S_IWUSR); 111 MODULE_PARM_DESC(max_report_luns, 112 "REPORT LUNS maximum number of LUNS received (should be" 113 " between 1 and 16384)"); 114 115 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18; 116 117 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); 118 MODULE_PARM_DESC(inq_timeout, 119 "Timeout (in seconds) waiting for devices to answer INQUIRY." 120 " Default is 20. Some devices may need more; most need less."); 121 122 /* This lock protects only this list */ 123 static DEFINE_SPINLOCK(async_scan_lock); 124 static LIST_HEAD(scanning_hosts); 125 126 struct async_scan_data { 127 struct list_head list; 128 struct Scsi_Host *shost; 129 struct completion prev_finished; 130 }; 131 132 /** 133 * scsi_complete_async_scans - Wait for asynchronous scans to complete 134 * 135 * When this function returns, any host which started scanning before 136 * this function was called will have finished its scan. Hosts which 137 * started scanning after this function was called may or may not have 138 * finished. 139 */ 140 int scsi_complete_async_scans(void) 141 { 142 struct async_scan_data *data; 143 144 do { 145 if (list_empty(&scanning_hosts)) 146 return 0; 147 /* If we can't get memory immediately, that's OK. Just 148 * sleep a little. Even if we never get memory, the async 149 * scans will finish eventually. 150 */ 151 data = kmalloc(sizeof(*data), GFP_KERNEL); 152 if (!data) 153 msleep(1); 154 } while (!data); 155 156 data->shost = NULL; 157 init_completion(&data->prev_finished); 158 159 spin_lock(&async_scan_lock); 160 /* Check that there's still somebody else on the list */ 161 if (list_empty(&scanning_hosts)) 162 goto done; 163 list_add_tail(&data->list, &scanning_hosts); 164 spin_unlock(&async_scan_lock); 165 166 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); 167 wait_for_completion(&data->prev_finished); 168 169 spin_lock(&async_scan_lock); 170 list_del(&data->list); 171 if (!list_empty(&scanning_hosts)) { 172 struct async_scan_data *next = list_entry(scanning_hosts.next, 173 struct async_scan_data, list); 174 complete(&next->prev_finished); 175 } 176 done: 177 spin_unlock(&async_scan_lock); 178 179 kfree(data); 180 return 0; 181 } 182 183 /** 184 * scsi_unlock_floptical - unlock device via a special MODE SENSE command 185 * @sdev: scsi device to send command to 186 * @result: area to store the result of the MODE SENSE 187 * 188 * Description: 189 * Send a vendor specific MODE SENSE (not a MODE SELECT) command. 190 * Called for BLIST_KEY devices. 191 **/ 192 static void scsi_unlock_floptical(struct scsi_device *sdev, 193 unsigned char *result) 194 { 195 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 196 197 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n"); 198 scsi_cmd[0] = MODE_SENSE; 199 scsi_cmd[1] = 0; 200 scsi_cmd[2] = 0x2e; 201 scsi_cmd[3] = 0; 202 scsi_cmd[4] = 0x2a; /* size */ 203 scsi_cmd[5] = 0; 204 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, 205 SCSI_TIMEOUT, 3, NULL); 206 } 207 208 /** 209 * scsi_alloc_sdev - allocate and setup a scsi_Device 210 * @starget: which target to allocate a &scsi_device for 211 * @lun: which lun 212 * @hostdata: usually NULL and set by ->slave_alloc instead 213 * 214 * Description: 215 * Allocate, initialize for io, and return a pointer to a scsi_Device. 216 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and 217 * adds scsi_Device to the appropriate list. 218 * 219 * Return value: 220 * scsi_Device pointer, or NULL on failure. 221 **/ 222 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, 223 u64 lun, void *hostdata) 224 { 225 struct scsi_device *sdev; 226 int display_failure_msg = 1, ret; 227 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 228 extern void scsi_evt_thread(struct work_struct *work); 229 extern void scsi_requeue_run_queue(struct work_struct *work); 230 231 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, 232 GFP_ATOMIC); 233 if (!sdev) 234 goto out; 235 236 sdev->vendor = scsi_null_device_strs; 237 sdev->model = scsi_null_device_strs; 238 sdev->rev = scsi_null_device_strs; 239 sdev->host = shost; 240 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD; 241 sdev->id = starget->id; 242 sdev->lun = lun; 243 sdev->channel = starget->channel; 244 sdev->sdev_state = SDEV_CREATED; 245 INIT_LIST_HEAD(&sdev->siblings); 246 INIT_LIST_HEAD(&sdev->same_target_siblings); 247 INIT_LIST_HEAD(&sdev->cmd_list); 248 INIT_LIST_HEAD(&sdev->starved_entry); 249 INIT_LIST_HEAD(&sdev->event_list); 250 spin_lock_init(&sdev->list_lock); 251 INIT_WORK(&sdev->event_work, scsi_evt_thread); 252 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue); 253 254 sdev->sdev_gendev.parent = get_device(&starget->dev); 255 sdev->sdev_target = starget; 256 257 /* usually NULL and set by ->slave_alloc instead */ 258 sdev->hostdata = hostdata; 259 260 /* if the device needs this changing, it may do so in the 261 * slave_configure function */ 262 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; 263 264 /* 265 * Some low level driver could use device->type 266 */ 267 sdev->type = -1; 268 269 /* 270 * Assume that the device will have handshaking problems, 271 * and then fix this field later if it turns out it 272 * doesn't 273 */ 274 sdev->borken = 1; 275 276 if (shost_use_blk_mq(shost)) 277 sdev->request_queue = scsi_mq_alloc_queue(sdev); 278 else 279 sdev->request_queue = scsi_alloc_queue(sdev); 280 if (!sdev->request_queue) { 281 /* release fn is set up in scsi_sysfs_device_initialise, so 282 * have to free and put manually here */ 283 put_device(&starget->dev); 284 kfree(sdev); 285 goto out; 286 } 287 WARN_ON_ONCE(!blk_get_queue(sdev->request_queue)); 288 sdev->request_queue->queuedata = sdev; 289 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); 290 291 scsi_sysfs_device_initialize(sdev); 292 293 if (shost->hostt->slave_alloc) { 294 ret = shost->hostt->slave_alloc(sdev); 295 if (ret) { 296 /* 297 * if LLDD reports slave not present, don't clutter 298 * console with alloc failure messages 299 */ 300 if (ret == -ENXIO) 301 display_failure_msg = 0; 302 goto out_device_destroy; 303 } 304 } 305 306 return sdev; 307 308 out_device_destroy: 309 __scsi_remove_device(sdev); 310 out: 311 if (display_failure_msg) 312 printk(ALLOC_FAILURE_MSG, __func__); 313 return NULL; 314 } 315 316 static void scsi_target_destroy(struct scsi_target *starget) 317 { 318 struct device *dev = &starget->dev; 319 struct Scsi_Host *shost = dev_to_shost(dev->parent); 320 unsigned long flags; 321 322 starget->state = STARGET_DEL; 323 transport_destroy_device(dev); 324 spin_lock_irqsave(shost->host_lock, flags); 325 if (shost->hostt->target_destroy) 326 shost->hostt->target_destroy(starget); 327 list_del_init(&starget->siblings); 328 spin_unlock_irqrestore(shost->host_lock, flags); 329 put_device(dev); 330 } 331 332 static void scsi_target_dev_release(struct device *dev) 333 { 334 struct device *parent = dev->parent; 335 struct scsi_target *starget = to_scsi_target(dev); 336 337 kfree(starget); 338 put_device(parent); 339 } 340 341 static struct device_type scsi_target_type = { 342 .name = "scsi_target", 343 .release = scsi_target_dev_release, 344 }; 345 346 int scsi_is_target_device(const struct device *dev) 347 { 348 return dev->type == &scsi_target_type; 349 } 350 EXPORT_SYMBOL(scsi_is_target_device); 351 352 static struct scsi_target *__scsi_find_target(struct device *parent, 353 int channel, uint id) 354 { 355 struct scsi_target *starget, *found_starget = NULL; 356 struct Scsi_Host *shost = dev_to_shost(parent); 357 /* 358 * Search for an existing target for this sdev. 359 */ 360 list_for_each_entry(starget, &shost->__targets, siblings) { 361 if (starget->id == id && 362 starget->channel == channel) { 363 found_starget = starget; 364 break; 365 } 366 } 367 if (found_starget) 368 get_device(&found_starget->dev); 369 370 return found_starget; 371 } 372 373 /** 374 * scsi_target_reap_ref_release - remove target from visibility 375 * @kref: the reap_ref in the target being released 376 * 377 * Called on last put of reap_ref, which is the indication that no device 378 * under this target is visible anymore, so render the target invisible in 379 * sysfs. Note: we have to be in user context here because the target reaps 380 * should be done in places where the scsi device visibility is being removed. 381 */ 382 static void scsi_target_reap_ref_release(struct kref *kref) 383 { 384 struct scsi_target *starget 385 = container_of(kref, struct scsi_target, reap_ref); 386 387 /* 388 * if we get here and the target is still in the CREATED state that 389 * means it was allocated but never made visible (because a scan 390 * turned up no LUNs), so don't call device_del() on it. 391 */ 392 if (starget->state != STARGET_CREATED) { 393 transport_remove_device(&starget->dev); 394 device_del(&starget->dev); 395 } 396 scsi_target_destroy(starget); 397 } 398 399 static void scsi_target_reap_ref_put(struct scsi_target *starget) 400 { 401 kref_put(&starget->reap_ref, scsi_target_reap_ref_release); 402 } 403 404 /** 405 * scsi_alloc_target - allocate a new or find an existing target 406 * @parent: parent of the target (need not be a scsi host) 407 * @channel: target channel number (zero if no channels) 408 * @id: target id number 409 * 410 * Return an existing target if one exists, provided it hasn't already 411 * gone into STARGET_DEL state, otherwise allocate a new target. 412 * 413 * The target is returned with an incremented reference, so the caller 414 * is responsible for both reaping and doing a last put 415 */ 416 static struct scsi_target *scsi_alloc_target(struct device *parent, 417 int channel, uint id) 418 { 419 struct Scsi_Host *shost = dev_to_shost(parent); 420 struct device *dev = NULL; 421 unsigned long flags; 422 const int size = sizeof(struct scsi_target) 423 + shost->transportt->target_size; 424 struct scsi_target *starget; 425 struct scsi_target *found_target; 426 int error, ref_got; 427 428 starget = kzalloc(size, GFP_KERNEL); 429 if (!starget) { 430 printk(KERN_ERR "%s: allocation failure\n", __func__); 431 return NULL; 432 } 433 dev = &starget->dev; 434 device_initialize(dev); 435 kref_init(&starget->reap_ref); 436 dev->parent = get_device(parent); 437 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); 438 dev->bus = &scsi_bus_type; 439 dev->type = &scsi_target_type; 440 starget->id = id; 441 starget->channel = channel; 442 starget->can_queue = 0; 443 INIT_LIST_HEAD(&starget->siblings); 444 INIT_LIST_HEAD(&starget->devices); 445 starget->state = STARGET_CREATED; 446 starget->scsi_level = SCSI_2; 447 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; 448 retry: 449 spin_lock_irqsave(shost->host_lock, flags); 450 451 found_target = __scsi_find_target(parent, channel, id); 452 if (found_target) 453 goto found; 454 455 list_add_tail(&starget->siblings, &shost->__targets); 456 spin_unlock_irqrestore(shost->host_lock, flags); 457 /* allocate and add */ 458 transport_setup_device(dev); 459 if (shost->hostt->target_alloc) { 460 error = shost->hostt->target_alloc(starget); 461 462 if(error) { 463 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error); 464 /* don't want scsi_target_reap to do the final 465 * put because it will be under the host lock */ 466 scsi_target_destroy(starget); 467 return NULL; 468 } 469 } 470 get_device(dev); 471 472 return starget; 473 474 found: 475 /* 476 * release routine already fired if kref is zero, so if we can still 477 * take the reference, the target must be alive. If we can't, it must 478 * be dying and we need to wait for a new target 479 */ 480 ref_got = kref_get_unless_zero(&found_target->reap_ref); 481 482 spin_unlock_irqrestore(shost->host_lock, flags); 483 if (ref_got) { 484 put_device(dev); 485 return found_target; 486 } 487 /* 488 * Unfortunately, we found a dying target; need to wait until it's 489 * dead before we can get a new one. There is an anomaly here. We 490 * *should* call scsi_target_reap() to balance the kref_get() of the 491 * reap_ref above. However, since the target being released, it's 492 * already invisible and the reap_ref is irrelevant. If we call 493 * scsi_target_reap() we might spuriously do another device_del() on 494 * an already invisible target. 495 */ 496 put_device(&found_target->dev); 497 /* 498 * length of time is irrelevant here, we just want to yield the CPU 499 * for a tick to avoid busy waiting for the target to die. 500 */ 501 msleep(1); 502 goto retry; 503 } 504 505 /** 506 * scsi_target_reap - check to see if target is in use and destroy if not 507 * @starget: target to be checked 508 * 509 * This is used after removing a LUN or doing a last put of the target 510 * it checks atomically that nothing is using the target and removes 511 * it if so. 512 */ 513 void scsi_target_reap(struct scsi_target *starget) 514 { 515 /* 516 * serious problem if this triggers: STARGET_DEL is only set in the if 517 * the reap_ref drops to zero, so we're trying to do another final put 518 * on an already released kref 519 */ 520 BUG_ON(starget->state == STARGET_DEL); 521 scsi_target_reap_ref_put(starget); 522 } 523 524 /** 525 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string 526 * @s: INQUIRY result string to sanitize 527 * @len: length of the string 528 * 529 * Description: 530 * The SCSI spec says that INQUIRY vendor, product, and revision 531 * strings must consist entirely of graphic ASCII characters, 532 * padded on the right with spaces. Since not all devices obey 533 * this rule, we will replace non-graphic or non-ASCII characters 534 * with spaces. Exception: a NUL character is interpreted as a 535 * string terminator, so all the following characters are set to 536 * spaces. 537 **/ 538 static void sanitize_inquiry_string(unsigned char *s, int len) 539 { 540 int terminated = 0; 541 542 for (; len > 0; (--len, ++s)) { 543 if (*s == 0) 544 terminated = 1; 545 if (terminated || *s < 0x20 || *s > 0x7e) 546 *s = ' '; 547 } 548 } 549 550 /** 551 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY 552 * @sdev: scsi_device to probe 553 * @inq_result: area to store the INQUIRY result 554 * @result_len: len of inq_result 555 * @bflags: store any bflags found here 556 * 557 * Description: 558 * Probe the lun associated with @req using a standard SCSI INQUIRY; 559 * 560 * If the INQUIRY is successful, zero is returned and the 561 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length 562 * are copied to the scsi_device any flags value is stored in *@bflags. 563 **/ 564 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, 565 int result_len, int *bflags) 566 { 567 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 568 int first_inquiry_len, try_inquiry_len, next_inquiry_len; 569 int response_len = 0; 570 int pass, count, result; 571 struct scsi_sense_hdr sshdr; 572 573 *bflags = 0; 574 575 /* Perform up to 3 passes. The first pass uses a conservative 576 * transfer length of 36 unless sdev->inquiry_len specifies a 577 * different value. */ 578 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; 579 try_inquiry_len = first_inquiry_len; 580 pass = 1; 581 582 next_pass: 583 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 584 "scsi scan: INQUIRY pass %d length %d\n", 585 pass, try_inquiry_len)); 586 587 /* Each pass gets up to three chances to ignore Unit Attention */ 588 for (count = 0; count < 3; ++count) { 589 int resid; 590 591 memset(scsi_cmd, 0, 6); 592 scsi_cmd[0] = INQUIRY; 593 scsi_cmd[4] = (unsigned char) try_inquiry_len; 594 595 memset(inq_result, 0, try_inquiry_len); 596 597 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 598 inq_result, try_inquiry_len, &sshdr, 599 HZ / 2 + HZ * scsi_inq_timeout, 3, 600 &resid); 601 602 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 603 "scsi scan: INQUIRY %s with code 0x%x\n", 604 result ? "failed" : "successful", result)); 605 606 if (result) { 607 /* 608 * not-ready to ready transition [asc/ascq=0x28/0x0] 609 * or power-on, reset [asc/ascq=0x29/0x0], continue. 610 * INQUIRY should not yield UNIT_ATTENTION 611 * but many buggy devices do so anyway. 612 */ 613 if ((driver_byte(result) & DRIVER_SENSE) && 614 scsi_sense_valid(&sshdr)) { 615 if ((sshdr.sense_key == UNIT_ATTENTION) && 616 ((sshdr.asc == 0x28) || 617 (sshdr.asc == 0x29)) && 618 (sshdr.ascq == 0)) 619 continue; 620 } 621 } else { 622 /* 623 * if nothing was transferred, we try 624 * again. It's a workaround for some USB 625 * devices. 626 */ 627 if (resid == try_inquiry_len) 628 continue; 629 } 630 break; 631 } 632 633 if (result == 0) { 634 sanitize_inquiry_string(&inq_result[8], 8); 635 sanitize_inquiry_string(&inq_result[16], 16); 636 sanitize_inquiry_string(&inq_result[32], 4); 637 638 response_len = inq_result[4] + 5; 639 if (response_len > 255) 640 response_len = first_inquiry_len; /* sanity */ 641 642 /* 643 * Get any flags for this device. 644 * 645 * XXX add a bflags to scsi_device, and replace the 646 * corresponding bit fields in scsi_device, so bflags 647 * need not be passed as an argument. 648 */ 649 *bflags = scsi_get_device_flags(sdev, &inq_result[8], 650 &inq_result[16]); 651 652 /* When the first pass succeeds we gain information about 653 * what larger transfer lengths might work. */ 654 if (pass == 1) { 655 if (BLIST_INQUIRY_36 & *bflags) 656 next_inquiry_len = 36; 657 else if (BLIST_INQUIRY_58 & *bflags) 658 next_inquiry_len = 58; 659 else if (sdev->inquiry_len) 660 next_inquiry_len = sdev->inquiry_len; 661 else 662 next_inquiry_len = response_len; 663 664 /* If more data is available perform the second pass */ 665 if (next_inquiry_len > try_inquiry_len) { 666 try_inquiry_len = next_inquiry_len; 667 pass = 2; 668 goto next_pass; 669 } 670 } 671 672 } else if (pass == 2) { 673 sdev_printk(KERN_INFO, sdev, 674 "scsi scan: %d byte inquiry failed. " 675 "Consider BLIST_INQUIRY_36 for this device\n", 676 try_inquiry_len); 677 678 /* If this pass failed, the third pass goes back and transfers 679 * the same amount as we successfully got in the first pass. */ 680 try_inquiry_len = first_inquiry_len; 681 pass = 3; 682 goto next_pass; 683 } 684 685 /* If the last transfer attempt got an error, assume the 686 * peripheral doesn't exist or is dead. */ 687 if (result) 688 return -EIO; 689 690 /* Don't report any more data than the device says is valid */ 691 sdev->inquiry_len = min(try_inquiry_len, response_len); 692 693 /* 694 * XXX Abort if the response length is less than 36? If less than 695 * 32, the lookup of the device flags (above) could be invalid, 696 * and it would be possible to take an incorrect action - we do 697 * not want to hang because of a short INQUIRY. On the flip side, 698 * if the device is spun down or becoming ready (and so it gives a 699 * short INQUIRY), an abort here prevents any further use of the 700 * device, including spin up. 701 * 702 * On the whole, the best approach seems to be to assume the first 703 * 36 bytes are valid no matter what the device says. That's 704 * better than copying < 36 bytes to the inquiry-result buffer 705 * and displaying garbage for the Vendor, Product, or Revision 706 * strings. 707 */ 708 if (sdev->inquiry_len < 36) { 709 sdev_printk(KERN_INFO, sdev, 710 "scsi scan: INQUIRY result too short (%d)," 711 " using 36\n", sdev->inquiry_len); 712 sdev->inquiry_len = 36; 713 } 714 715 /* 716 * Related to the above issue: 717 * 718 * XXX Devices (disk or all?) should be sent a TEST UNIT READY, 719 * and if not ready, sent a START_STOP to start (maybe spin up) and 720 * then send the INQUIRY again, since the INQUIRY can change after 721 * a device is initialized. 722 * 723 * Ideally, start a device if explicitly asked to do so. This 724 * assumes that a device is spun up on power on, spun down on 725 * request, and then spun up on request. 726 */ 727 728 /* 729 * The scanning code needs to know the scsi_level, even if no 730 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so 731 * non-zero LUNs can be scanned. 732 */ 733 sdev->scsi_level = inq_result[2] & 0x07; 734 if (sdev->scsi_level >= 2 || 735 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) 736 sdev->scsi_level++; 737 sdev->sdev_target->scsi_level = sdev->scsi_level; 738 739 return 0; 740 } 741 742 /** 743 * scsi_add_lun - allocate and fully initialze a scsi_device 744 * @sdev: holds information to be stored in the new scsi_device 745 * @inq_result: holds the result of a previous INQUIRY to the LUN 746 * @bflags: black/white list flag 747 * @async: 1 if this device is being scanned asynchronously 748 * 749 * Description: 750 * Initialize the scsi_device @sdev. Optionally set fields based 751 * on values in *@bflags. 752 * 753 * Return: 754 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 755 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 756 **/ 757 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, 758 int *bflags, int async) 759 { 760 int ret; 761 762 /* 763 * XXX do not save the inquiry, since it can change underneath us, 764 * save just vendor/model/rev. 765 * 766 * Rather than save it and have an ioctl that retrieves the saved 767 * value, have an ioctl that executes the same INQUIRY code used 768 * in scsi_probe_lun, let user level programs doing INQUIRY 769 * scanning run at their own risk, or supply a user level program 770 * that can correctly scan. 771 */ 772 773 /* 774 * Copy at least 36 bytes of INQUIRY data, so that we don't 775 * dereference unallocated memory when accessing the Vendor, 776 * Product, and Revision strings. Badly behaved devices may set 777 * the INQUIRY Additional Length byte to a small value, indicating 778 * these strings are invalid, but often they contain plausible data 779 * nonetheless. It doesn't matter if the device sent < 36 bytes 780 * total, since scsi_probe_lun() initializes inq_result with 0s. 781 */ 782 sdev->inquiry = kmemdup(inq_result, 783 max_t(size_t, sdev->inquiry_len, 36), 784 GFP_ATOMIC); 785 if (sdev->inquiry == NULL) 786 return SCSI_SCAN_NO_RESPONSE; 787 788 sdev->vendor = (char *) (sdev->inquiry + 8); 789 sdev->model = (char *) (sdev->inquiry + 16); 790 sdev->rev = (char *) (sdev->inquiry + 32); 791 792 if (strncmp(sdev->vendor, "ATA ", 8) == 0) { 793 /* 794 * sata emulation layer device. This is a hack to work around 795 * the SATL power management specifications which state that 796 * when the SATL detects the device has gone into standby 797 * mode, it shall respond with NOT READY. 798 */ 799 sdev->allow_restart = 1; 800 } 801 802 if (*bflags & BLIST_ISROM) { 803 sdev->type = TYPE_ROM; 804 sdev->removable = 1; 805 } else { 806 sdev->type = (inq_result[0] & 0x1f); 807 sdev->removable = (inq_result[1] & 0x80) >> 7; 808 } 809 810 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { 811 /* RBC and MMC devices can return SCSI-3 compliance and yet 812 * still not support REPORT LUNS, so make them act as 813 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is 814 * specifically set */ 815 if ((*bflags & BLIST_REPORTLUN2) == 0) 816 *bflags |= BLIST_NOREPORTLUN; 817 } 818 819 /* 820 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI 821 * spec says: The device server is capable of supporting the 822 * specified peripheral device type on this logical unit. However, 823 * the physical device is not currently connected to this logical 824 * unit. 825 * 826 * The above is vague, as it implies that we could treat 001 and 827 * 011 the same. Stay compatible with previous code, and create a 828 * scsi_device for a PQ of 1 829 * 830 * Don't set the device offline here; rather let the upper 831 * level drivers eval the PQ to decide whether they should 832 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. 833 */ 834 835 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; 836 sdev->lockable = sdev->removable; 837 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); 838 839 if (sdev->scsi_level >= SCSI_3 || 840 (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) 841 sdev->ppr = 1; 842 if (inq_result[7] & 0x60) 843 sdev->wdtr = 1; 844 if (inq_result[7] & 0x10) 845 sdev->sdtr = 1; 846 847 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " 848 "ANSI: %d%s\n", scsi_device_type(sdev->type), 849 sdev->vendor, sdev->model, sdev->rev, 850 sdev->inq_periph_qual, inq_result[2] & 0x07, 851 (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); 852 853 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && 854 !(*bflags & BLIST_NOTQ)) 855 sdev->tagged_supported = 1; 856 857 /* 858 * Some devices (Texel CD ROM drives) have handshaking problems 859 * when used with the Seagate controllers. borken is initialized 860 * to 1, and then set it to 0 here. 861 */ 862 if ((*bflags & BLIST_BORKEN) == 0) 863 sdev->borken = 0; 864 865 if (*bflags & BLIST_NO_ULD_ATTACH) 866 sdev->no_uld_attach = 1; 867 868 /* 869 * Apparently some really broken devices (contrary to the SCSI 870 * standards) need to be selected without asserting ATN 871 */ 872 if (*bflags & BLIST_SELECT_NO_ATN) 873 sdev->select_no_atn = 1; 874 875 /* 876 * Maximum 512 sector transfer length 877 * broken RA4x00 Compaq Disk Array 878 */ 879 if (*bflags & BLIST_MAX_512) 880 blk_queue_max_hw_sectors(sdev->request_queue, 512); 881 882 /* 883 * Some devices may not want to have a start command automatically 884 * issued when a device is added. 885 */ 886 if (*bflags & BLIST_NOSTARTONADD) 887 sdev->no_start_on_add = 1; 888 889 if (*bflags & BLIST_SINGLELUN) 890 scsi_target(sdev)->single_lun = 1; 891 892 sdev->use_10_for_rw = 1; 893 894 if (*bflags & BLIST_MS_SKIP_PAGE_08) 895 sdev->skip_ms_page_8 = 1; 896 897 if (*bflags & BLIST_MS_SKIP_PAGE_3F) 898 sdev->skip_ms_page_3f = 1; 899 900 if (*bflags & BLIST_USE_10_BYTE_MS) 901 sdev->use_10_for_ms = 1; 902 903 /* some devices don't like REPORT SUPPORTED OPERATION CODES 904 * and will simply timeout causing sd_mod init to take a very 905 * very long time */ 906 if (*bflags & BLIST_NO_RSOC) 907 sdev->no_report_opcodes = 1; 908 909 /* set the device running here so that slave configure 910 * may do I/O */ 911 ret = scsi_device_set_state(sdev, SDEV_RUNNING); 912 if (ret) { 913 ret = scsi_device_set_state(sdev, SDEV_BLOCK); 914 915 if (ret) { 916 sdev_printk(KERN_ERR, sdev, 917 "in wrong state %s to complete scan\n", 918 scsi_device_state_name(sdev->sdev_state)); 919 return SCSI_SCAN_NO_RESPONSE; 920 } 921 } 922 923 if (*bflags & BLIST_MS_192_BYTES_FOR_3F) 924 sdev->use_192_bytes_for_3f = 1; 925 926 if (*bflags & BLIST_NOT_LOCKABLE) 927 sdev->lockable = 0; 928 929 if (*bflags & BLIST_RETRY_HWERROR) 930 sdev->retry_hwerror = 1; 931 932 if (*bflags & BLIST_NO_DIF) 933 sdev->no_dif = 1; 934 935 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; 936 937 if (*bflags & BLIST_TRY_VPD_PAGES) 938 sdev->try_vpd_pages = 1; 939 else if (*bflags & BLIST_SKIP_VPD_PAGES) 940 sdev->skip_vpd_pages = 1; 941 942 transport_configure_device(&sdev->sdev_gendev); 943 944 if (sdev->host->hostt->slave_configure) { 945 ret = sdev->host->hostt->slave_configure(sdev); 946 if (ret) { 947 /* 948 * if LLDD reports slave not present, don't clutter 949 * console with alloc failure messages 950 */ 951 if (ret != -ENXIO) { 952 sdev_printk(KERN_ERR, sdev, 953 "failed to configure device\n"); 954 } 955 return SCSI_SCAN_NO_RESPONSE; 956 } 957 } 958 959 if (sdev->scsi_level >= SCSI_3) 960 scsi_attach_vpd(sdev); 961 962 sdev->max_queue_depth = sdev->queue_depth; 963 964 /* 965 * Ok, the device is now all set up, we can 966 * register it and tell the rest of the kernel 967 * about it. 968 */ 969 if (!async && scsi_sysfs_add_sdev(sdev) != 0) 970 return SCSI_SCAN_NO_RESPONSE; 971 972 return SCSI_SCAN_LUN_PRESENT; 973 } 974 975 #ifdef CONFIG_SCSI_LOGGING 976 /** 977 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace 978 * @buf: Output buffer with at least end-first+1 bytes of space 979 * @inq: Inquiry buffer (input) 980 * @first: Offset of string into inq 981 * @end: Index after last character in inq 982 */ 983 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, 984 unsigned first, unsigned end) 985 { 986 unsigned term = 0, idx; 987 988 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { 989 if (inq[idx+first] > ' ') { 990 buf[idx] = inq[idx+first]; 991 term = idx+1; 992 } else { 993 buf[idx] = ' '; 994 } 995 } 996 buf[term] = 0; 997 return buf; 998 } 999 #endif 1000 1001 /** 1002 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it 1003 * @starget: pointer to target device structure 1004 * @lun: LUN of target device 1005 * @bflagsp: store bflags here if not NULL 1006 * @sdevp: probe the LUN corresponding to this scsi_device 1007 * @rescan: if nonzero skip some code only needed on first scan 1008 * @hostdata: passed to scsi_alloc_sdev() 1009 * 1010 * Description: 1011 * Call scsi_probe_lun, if a LUN with an attached device is found, 1012 * allocate and set it up by calling scsi_add_lun. 1013 * 1014 * Return: 1015 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 1016 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is 1017 * attached at the LUN 1018 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 1019 **/ 1020 static int scsi_probe_and_add_lun(struct scsi_target *starget, 1021 u64 lun, int *bflagsp, 1022 struct scsi_device **sdevp, int rescan, 1023 void *hostdata) 1024 { 1025 struct scsi_device *sdev; 1026 unsigned char *result; 1027 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256; 1028 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1029 1030 /* 1031 * The rescan flag is used as an optimization, the first scan of a 1032 * host adapter calls into here with rescan == 0. 1033 */ 1034 sdev = scsi_device_lookup_by_target(starget, lun); 1035 if (sdev) { 1036 if (rescan || !scsi_device_created(sdev)) { 1037 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1038 "scsi scan: device exists on %s\n", 1039 dev_name(&sdev->sdev_gendev))); 1040 if (sdevp) 1041 *sdevp = sdev; 1042 else 1043 scsi_device_put(sdev); 1044 1045 if (bflagsp) 1046 *bflagsp = scsi_get_device_flags(sdev, 1047 sdev->vendor, 1048 sdev->model); 1049 return SCSI_SCAN_LUN_PRESENT; 1050 } 1051 scsi_device_put(sdev); 1052 } else 1053 sdev = scsi_alloc_sdev(starget, lun, hostdata); 1054 if (!sdev) 1055 goto out; 1056 1057 result = kmalloc(result_len, GFP_ATOMIC | 1058 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0)); 1059 if (!result) 1060 goto out_free_sdev; 1061 1062 if (scsi_probe_lun(sdev, result, result_len, &bflags)) 1063 goto out_free_result; 1064 1065 if (bflagsp) 1066 *bflagsp = bflags; 1067 /* 1068 * result contains valid SCSI INQUIRY data. 1069 */ 1070 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) { 1071 /* 1072 * For a Peripheral qualifier 3 (011b), the SCSI 1073 * spec says: The device server is not capable of 1074 * supporting a physical device on this logical 1075 * unit. 1076 * 1077 * For disks, this implies that there is no 1078 * logical disk configured at sdev->lun, but there 1079 * is a target id responding. 1080 */ 1081 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" 1082 " peripheral qualifier of 3, device not" 1083 " added\n")) 1084 if (lun == 0) { 1085 SCSI_LOG_SCAN_BUS(1, { 1086 unsigned char vend[9]; 1087 unsigned char mod[17]; 1088 1089 sdev_printk(KERN_INFO, sdev, 1090 "scsi scan: consider passing scsi_mod." 1091 "dev_flags=%s:%s:0x240 or 0x1000240\n", 1092 scsi_inq_str(vend, result, 8, 16), 1093 scsi_inq_str(mod, result, 16, 32)); 1094 }); 1095 1096 } 1097 1098 res = SCSI_SCAN_TARGET_PRESENT; 1099 goto out_free_result; 1100 } 1101 1102 /* 1103 * Some targets may set slight variations of PQ and PDT to signal 1104 * that no LUN is present, so don't add sdev in these cases. 1105 * Two specific examples are: 1106 * 1) NetApp targets: return PQ=1, PDT=0x1f 1107 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" 1108 * in the UFI 1.0 spec (we cannot rely on reserved bits). 1109 * 1110 * References: 1111 * 1) SCSI SPC-3, pp. 145-146 1112 * PQ=1: "A peripheral device having the specified peripheral 1113 * device type is not connected to this logical unit. However, the 1114 * device server is capable of supporting the specified peripheral 1115 * device type on this logical unit." 1116 * PDT=0x1f: "Unknown or no device type" 1117 * 2) USB UFI 1.0, p. 20 1118 * PDT=00h Direct-access device (floppy) 1119 * PDT=1Fh none (no FDD connected to the requested logical unit) 1120 */ 1121 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) && 1122 (result[0] & 0x1f) == 0x1f && 1123 !scsi_is_wlun(lun)) { 1124 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1125 "scsi scan: peripheral device type" 1126 " of 31, no device added\n")); 1127 res = SCSI_SCAN_TARGET_PRESENT; 1128 goto out_free_result; 1129 } 1130 1131 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); 1132 if (res == SCSI_SCAN_LUN_PRESENT) { 1133 if (bflags & BLIST_KEY) { 1134 sdev->lockable = 0; 1135 scsi_unlock_floptical(sdev, result); 1136 } 1137 } 1138 1139 out_free_result: 1140 kfree(result); 1141 out_free_sdev: 1142 if (res == SCSI_SCAN_LUN_PRESENT) { 1143 if (sdevp) { 1144 if (scsi_device_get(sdev) == 0) { 1145 *sdevp = sdev; 1146 } else { 1147 __scsi_remove_device(sdev); 1148 res = SCSI_SCAN_NO_RESPONSE; 1149 } 1150 } 1151 } else 1152 __scsi_remove_device(sdev); 1153 out: 1154 return res; 1155 } 1156 1157 /** 1158 * scsi_sequential_lun_scan - sequentially scan a SCSI target 1159 * @starget: pointer to target structure to scan 1160 * @bflags: black/white list flag for LUN 0 1161 * @scsi_level: Which version of the standard does this device adhere to 1162 * @rescan: passed to scsi_probe_add_lun() 1163 * 1164 * Description: 1165 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been 1166 * scanned) to some maximum lun until a LUN is found with no device 1167 * attached. Use the bflags to figure out any oddities. 1168 * 1169 * Modifies sdevscan->lun. 1170 **/ 1171 static void scsi_sequential_lun_scan(struct scsi_target *starget, 1172 int bflags, int scsi_level, int rescan) 1173 { 1174 uint max_dev_lun; 1175 u64 sparse_lun, lun; 1176 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1177 1178 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget, 1179 "scsi scan: Sequential scan\n")); 1180 1181 max_dev_lun = min(max_scsi_luns, shost->max_lun); 1182 /* 1183 * If this device is known to support sparse multiple units, 1184 * override the other settings, and scan all of them. Normally, 1185 * SCSI-3 devices should be scanned via the REPORT LUNS. 1186 */ 1187 if (bflags & BLIST_SPARSELUN) { 1188 max_dev_lun = shost->max_lun; 1189 sparse_lun = 1; 1190 } else 1191 sparse_lun = 0; 1192 1193 /* 1194 * If less than SCSI_1_CSS, and no special lun scaning, stop 1195 * scanning; this matches 2.4 behaviour, but could just be a bug 1196 * (to continue scanning a SCSI_1_CSS device). 1197 * 1198 * This test is broken. We might not have any device on lun0 for 1199 * a sparselun device, and if that's the case then how would we 1200 * know the real scsi_level, eh? It might make sense to just not 1201 * scan any SCSI_1 device for non-0 luns, but that check would best 1202 * go into scsi_alloc_sdev() and just have it return null when asked 1203 * to alloc an sdev for lun > 0 on an already found SCSI_1 device. 1204 * 1205 if ((sdevscan->scsi_level < SCSI_1_CCS) && 1206 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) 1207 == 0)) 1208 return; 1209 */ 1210 /* 1211 * If this device is known to support multiple units, override 1212 * the other settings, and scan all of them. 1213 */ 1214 if (bflags & BLIST_FORCELUN) 1215 max_dev_lun = shost->max_lun; 1216 /* 1217 * REGAL CDC-4X: avoid hang after LUN 4 1218 */ 1219 if (bflags & BLIST_MAX5LUN) 1220 max_dev_lun = min(5U, max_dev_lun); 1221 /* 1222 * Do not scan SCSI-2 or lower device past LUN 7, unless 1223 * BLIST_LARGELUN. 1224 */ 1225 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) 1226 max_dev_lun = min(8U, max_dev_lun); 1227 1228 /* 1229 * Stop scanning at 255 unless BLIST_SCSI3LUN 1230 */ 1231 if (!(bflags & BLIST_SCSI3LUN)) 1232 max_dev_lun = min(256U, max_dev_lun); 1233 1234 /* 1235 * We have already scanned LUN 0, so start at LUN 1. Keep scanning 1236 * until we reach the max, or no LUN is found and we are not 1237 * sparse_lun. 1238 */ 1239 for (lun = 1; lun < max_dev_lun; ++lun) 1240 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, 1241 NULL) != SCSI_SCAN_LUN_PRESENT) && 1242 !sparse_lun) 1243 return; 1244 } 1245 1246 /** 1247 * scsilun_to_int - convert a scsi_lun to an int 1248 * @scsilun: struct scsi_lun to be converted. 1249 * 1250 * Description: 1251 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered 1252 * integer, and return the result. The caller must check for 1253 * truncation before using this function. 1254 * 1255 * Notes: 1256 * For a description of the LUN format, post SCSI-3 see the SCSI 1257 * Architecture Model, for SCSI-3 see the SCSI Controller Commands. 1258 * 1259 * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function 1260 * returns the integer: 0x0b03d204 1261 * 1262 * This encoding will return a standard integer LUN for LUNs smaller 1263 * than 256, which typically use a single level LUN structure with 1264 * addressing method 0. 1265 **/ 1266 u64 scsilun_to_int(struct scsi_lun *scsilun) 1267 { 1268 int i; 1269 u64 lun; 1270 1271 lun = 0; 1272 for (i = 0; i < sizeof(lun); i += 2) 1273 lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) | 1274 ((u64)scsilun->scsi_lun[i + 1] << (i * 8))); 1275 return lun; 1276 } 1277 EXPORT_SYMBOL(scsilun_to_int); 1278 1279 /** 1280 * int_to_scsilun - reverts an int into a scsi_lun 1281 * @lun: integer to be reverted 1282 * @scsilun: struct scsi_lun to be set. 1283 * 1284 * Description: 1285 * Reverts the functionality of the scsilun_to_int, which packed 1286 * an 8-byte lun value into an int. This routine unpacks the int 1287 * back into the lun value. 1288 * 1289 * Notes: 1290 * Given an integer : 0x0b03d204, this function returns a 1291 * struct scsi_lun of: d2 04 0b 03 00 00 00 00 1292 * 1293 **/ 1294 void int_to_scsilun(u64 lun, struct scsi_lun *scsilun) 1295 { 1296 int i; 1297 1298 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun)); 1299 1300 for (i = 0; i < sizeof(lun); i += 2) { 1301 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF; 1302 scsilun->scsi_lun[i+1] = lun & 0xFF; 1303 lun = lun >> 16; 1304 } 1305 } 1306 EXPORT_SYMBOL(int_to_scsilun); 1307 1308 /** 1309 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results 1310 * @starget: which target 1311 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN 1312 * @rescan: nonzero if we can skip code only needed on first scan 1313 * 1314 * Description: 1315 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. 1316 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. 1317 * 1318 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 1319 * LUNs even if it's older than SCSI-3. 1320 * If BLIST_NOREPORTLUN is set, return 1 always. 1321 * If BLIST_NOLUN is set, return 0 always. 1322 * If starget->no_report_luns is set, return 1 always. 1323 * 1324 * Return: 1325 * 0: scan completed (or no memory, so further scanning is futile) 1326 * 1: could not scan with REPORT LUN 1327 **/ 1328 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags, 1329 int rescan) 1330 { 1331 char devname[64]; 1332 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 1333 unsigned int length; 1334 u64 lun; 1335 unsigned int num_luns; 1336 unsigned int retries; 1337 int result; 1338 struct scsi_lun *lunp, *lun_data; 1339 u8 *data; 1340 struct scsi_sense_hdr sshdr; 1341 struct scsi_device *sdev; 1342 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 1343 int ret = 0; 1344 1345 /* 1346 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. 1347 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does 1348 * support more than 8 LUNs. 1349 * Don't attempt if the target doesn't support REPORT LUNS. 1350 */ 1351 if (bflags & BLIST_NOREPORTLUN) 1352 return 1; 1353 if (starget->scsi_level < SCSI_2 && 1354 starget->scsi_level != SCSI_UNKNOWN) 1355 return 1; 1356 if (starget->scsi_level < SCSI_3 && 1357 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) 1358 return 1; 1359 if (bflags & BLIST_NOLUN) 1360 return 0; 1361 if (starget->no_report_luns) 1362 return 1; 1363 1364 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { 1365 sdev = scsi_alloc_sdev(starget, 0, NULL); 1366 if (!sdev) 1367 return 0; 1368 if (scsi_device_get(sdev)) { 1369 __scsi_remove_device(sdev); 1370 return 0; 1371 } 1372 } 1373 1374 sprintf(devname, "host %d channel %d id %d", 1375 shost->host_no, sdev->channel, sdev->id); 1376 1377 /* 1378 * Allocate enough to hold the header (the same size as one scsi_lun) 1379 * plus the max number of luns we are requesting. 1380 * 1381 * Reallocating and trying again (with the exact amount we need) 1382 * would be nice, but then we need to somehow limit the size 1383 * allocated based on the available memory and the limits of 1384 * kmalloc - we don't want a kmalloc() failure of a huge value to 1385 * prevent us from finding any LUNs on this target. 1386 */ 1387 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun); 1388 lun_data = kmalloc(length, GFP_ATOMIC | 1389 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0)); 1390 if (!lun_data) { 1391 printk(ALLOC_FAILURE_MSG, __func__); 1392 goto out; 1393 } 1394 1395 scsi_cmd[0] = REPORT_LUNS; 1396 1397 /* 1398 * bytes 1 - 5: reserved, set to zero. 1399 */ 1400 memset(&scsi_cmd[1], 0, 5); 1401 1402 /* 1403 * bytes 6 - 9: length of the command. 1404 */ 1405 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff; 1406 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff; 1407 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff; 1408 scsi_cmd[9] = (unsigned char) length & 0xff; 1409 1410 scsi_cmd[10] = 0; /* reserved */ 1411 scsi_cmd[11] = 0; /* control */ 1412 1413 /* 1414 * We can get a UNIT ATTENTION, for example a power on/reset, so 1415 * retry a few times (like sd.c does for TEST UNIT READY). 1416 * Experience shows some combinations of adapter/devices get at 1417 * least two power on/resets. 1418 * 1419 * Illegal requests (for devices that do not support REPORT LUNS) 1420 * should come through as a check condition, and will not generate 1421 * a retry. 1422 */ 1423 for (retries = 0; retries < 3; retries++) { 1424 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1425 "scsi scan: Sending REPORT LUNS to (try %d)\n", 1426 retries)); 1427 1428 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 1429 lun_data, length, &sshdr, 1430 SCSI_TIMEOUT + 4 * HZ, 3, NULL); 1431 1432 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1433 "scsi scan: REPORT LUNS" 1434 " %s (try %d) result 0x%x\n", 1435 result ? "failed" : "successful", 1436 retries, result)); 1437 if (result == 0) 1438 break; 1439 else if (scsi_sense_valid(&sshdr)) { 1440 if (sshdr.sense_key != UNIT_ATTENTION) 1441 break; 1442 } 1443 } 1444 1445 if (result) { 1446 /* 1447 * The device probably does not support a REPORT LUN command 1448 */ 1449 ret = 1; 1450 goto out_err; 1451 } 1452 1453 /* 1454 * Get the length from the first four bytes of lun_data. 1455 */ 1456 data = (u8 *) lun_data->scsi_lun; 1457 length = ((data[0] << 24) | (data[1] << 16) | 1458 (data[2] << 8) | (data[3] << 0)); 1459 1460 num_luns = (length / sizeof(struct scsi_lun)); 1461 if (num_luns > max_scsi_report_luns) { 1462 sdev_printk(KERN_WARNING, sdev, 1463 "Only %d (max_scsi_report_luns)" 1464 " of %d luns reported, try increasing" 1465 " max_scsi_report_luns.\n", 1466 max_scsi_report_luns, num_luns); 1467 num_luns = max_scsi_report_luns; 1468 } 1469 1470 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1471 "scsi scan: REPORT LUN scan\n")); 1472 1473 /* 1474 * Scan the luns in lun_data. The entry at offset 0 is really 1475 * the header, so start at 1 and go up to and including num_luns. 1476 */ 1477 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { 1478 lun = scsilun_to_int(lunp); 1479 1480 if (lun > sdev->host->max_lun) { 1481 sdev_printk(KERN_WARNING, sdev, 1482 "lun%llu has a LUN larger than" 1483 " allowed by the host adapter\n", lun); 1484 } else { 1485 int res; 1486 1487 res = scsi_probe_and_add_lun(starget, 1488 lun, NULL, NULL, rescan, NULL); 1489 if (res == SCSI_SCAN_NO_RESPONSE) { 1490 /* 1491 * Got some results, but now none, abort. 1492 */ 1493 sdev_printk(KERN_ERR, sdev, 1494 "Unexpected response" 1495 " from lun %llu while scanning, scan" 1496 " aborted\n", (unsigned long long)lun); 1497 break; 1498 } 1499 } 1500 } 1501 1502 out_err: 1503 kfree(lun_data); 1504 out: 1505 scsi_device_put(sdev); 1506 if (scsi_device_created(sdev)) 1507 /* 1508 * the sdev we used didn't appear in the report luns scan 1509 */ 1510 __scsi_remove_device(sdev); 1511 return ret; 1512 } 1513 1514 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, 1515 uint id, u64 lun, void *hostdata) 1516 { 1517 struct scsi_device *sdev = ERR_PTR(-ENODEV); 1518 struct device *parent = &shost->shost_gendev; 1519 struct scsi_target *starget; 1520 1521 if (strncmp(scsi_scan_type, "none", 4) == 0) 1522 return ERR_PTR(-ENODEV); 1523 1524 starget = scsi_alloc_target(parent, channel, id); 1525 if (!starget) 1526 return ERR_PTR(-ENOMEM); 1527 scsi_autopm_get_target(starget); 1528 1529 mutex_lock(&shost->scan_mutex); 1530 if (!shost->async_scan) 1531 scsi_complete_async_scans(); 1532 1533 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1534 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); 1535 scsi_autopm_put_host(shost); 1536 } 1537 mutex_unlock(&shost->scan_mutex); 1538 scsi_autopm_put_target(starget); 1539 /* 1540 * paired with scsi_alloc_target(). Target will be destroyed unless 1541 * scsi_probe_and_add_lun made an underlying device visible 1542 */ 1543 scsi_target_reap(starget); 1544 put_device(&starget->dev); 1545 1546 return sdev; 1547 } 1548 EXPORT_SYMBOL(__scsi_add_device); 1549 1550 int scsi_add_device(struct Scsi_Host *host, uint channel, 1551 uint target, u64 lun) 1552 { 1553 struct scsi_device *sdev = 1554 __scsi_add_device(host, channel, target, lun, NULL); 1555 if (IS_ERR(sdev)) 1556 return PTR_ERR(sdev); 1557 1558 scsi_device_put(sdev); 1559 return 0; 1560 } 1561 EXPORT_SYMBOL(scsi_add_device); 1562 1563 void scsi_rescan_device(struct device *dev) 1564 { 1565 struct scsi_driver *drv; 1566 1567 if (!dev->driver) 1568 return; 1569 1570 drv = to_scsi_driver(dev->driver); 1571 if (try_module_get(drv->owner)) { 1572 if (drv->rescan) 1573 drv->rescan(dev); 1574 module_put(drv->owner); 1575 } 1576 } 1577 EXPORT_SYMBOL(scsi_rescan_device); 1578 1579 static void __scsi_scan_target(struct device *parent, unsigned int channel, 1580 unsigned int id, u64 lun, int rescan) 1581 { 1582 struct Scsi_Host *shost = dev_to_shost(parent); 1583 int bflags = 0; 1584 int res; 1585 struct scsi_target *starget; 1586 1587 if (shost->this_id == id) 1588 /* 1589 * Don't scan the host adapter 1590 */ 1591 return; 1592 1593 starget = scsi_alloc_target(parent, channel, id); 1594 if (!starget) 1595 return; 1596 scsi_autopm_get_target(starget); 1597 1598 if (lun != SCAN_WILD_CARD) { 1599 /* 1600 * Scan for a specific host/chan/id/lun. 1601 */ 1602 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); 1603 goto out_reap; 1604 } 1605 1606 /* 1607 * Scan LUN 0, if there is some response, scan further. Ideally, we 1608 * would not configure LUN 0 until all LUNs are scanned. 1609 */ 1610 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); 1611 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { 1612 if (scsi_report_lun_scan(starget, bflags, rescan) != 0) 1613 /* 1614 * The REPORT LUN did not scan the target, 1615 * do a sequential scan. 1616 */ 1617 scsi_sequential_lun_scan(starget, bflags, 1618 starget->scsi_level, rescan); 1619 } 1620 1621 out_reap: 1622 scsi_autopm_put_target(starget); 1623 /* 1624 * paired with scsi_alloc_target(): determine if the target has 1625 * any children at all and if not, nuke it 1626 */ 1627 scsi_target_reap(starget); 1628 1629 put_device(&starget->dev); 1630 } 1631 1632 /** 1633 * scsi_scan_target - scan a target id, possibly including all LUNs on the target. 1634 * @parent: host to scan 1635 * @channel: channel to scan 1636 * @id: target id to scan 1637 * @lun: Specific LUN to scan or SCAN_WILD_CARD 1638 * @rescan: passed to LUN scanning routines 1639 * 1640 * Description: 1641 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, 1642 * and possibly all LUNs on the target id. 1643 * 1644 * First try a REPORT LUN scan, if that does not scan the target, do a 1645 * sequential scan of LUNs on the target id. 1646 **/ 1647 void scsi_scan_target(struct device *parent, unsigned int channel, 1648 unsigned int id, u64 lun, int rescan) 1649 { 1650 struct Scsi_Host *shost = dev_to_shost(parent); 1651 1652 if (strncmp(scsi_scan_type, "none", 4) == 0) 1653 return; 1654 1655 mutex_lock(&shost->scan_mutex); 1656 if (!shost->async_scan) 1657 scsi_complete_async_scans(); 1658 1659 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1660 __scsi_scan_target(parent, channel, id, lun, rescan); 1661 scsi_autopm_put_host(shost); 1662 } 1663 mutex_unlock(&shost->scan_mutex); 1664 } 1665 EXPORT_SYMBOL(scsi_scan_target); 1666 1667 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, 1668 unsigned int id, u64 lun, int rescan) 1669 { 1670 uint order_id; 1671 1672 if (id == SCAN_WILD_CARD) 1673 for (id = 0; id < shost->max_id; ++id) { 1674 /* 1675 * XXX adapter drivers when possible (FCP, iSCSI) 1676 * could modify max_id to match the current max, 1677 * not the absolute max. 1678 * 1679 * XXX add a shost id iterator, so for example, 1680 * the FC ID can be the same as a target id 1681 * without a huge overhead of sparse id's. 1682 */ 1683 if (shost->reverse_ordering) 1684 /* 1685 * Scan from high to low id. 1686 */ 1687 order_id = shost->max_id - id - 1; 1688 else 1689 order_id = id; 1690 __scsi_scan_target(&shost->shost_gendev, channel, 1691 order_id, lun, rescan); 1692 } 1693 else 1694 __scsi_scan_target(&shost->shost_gendev, channel, 1695 id, lun, rescan); 1696 } 1697 1698 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, 1699 unsigned int id, u64 lun, int rescan) 1700 { 1701 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, 1702 "%s: <%u:%u:%llu>\n", 1703 __func__, channel, id, lun)); 1704 1705 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || 1706 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || 1707 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun))) 1708 return -EINVAL; 1709 1710 mutex_lock(&shost->scan_mutex); 1711 if (!shost->async_scan) 1712 scsi_complete_async_scans(); 1713 1714 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1715 if (channel == SCAN_WILD_CARD) 1716 for (channel = 0; channel <= shost->max_channel; 1717 channel++) 1718 scsi_scan_channel(shost, channel, id, lun, 1719 rescan); 1720 else 1721 scsi_scan_channel(shost, channel, id, lun, rescan); 1722 scsi_autopm_put_host(shost); 1723 } 1724 mutex_unlock(&shost->scan_mutex); 1725 1726 return 0; 1727 } 1728 1729 static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 1730 { 1731 struct scsi_device *sdev; 1732 shost_for_each_device(sdev, shost) { 1733 /* target removed before the device could be added */ 1734 if (sdev->sdev_state == SDEV_DEL) 1735 continue; 1736 if (!scsi_host_scan_allowed(shost) || 1737 scsi_sysfs_add_sdev(sdev) != 0) 1738 __scsi_remove_device(sdev); 1739 } 1740 } 1741 1742 /** 1743 * scsi_prep_async_scan - prepare for an async scan 1744 * @shost: the host which will be scanned 1745 * Returns: a cookie to be passed to scsi_finish_async_scan() 1746 * 1747 * Tells the midlayer this host is going to do an asynchronous scan. 1748 * It reserves the host's position in the scanning list and ensures 1749 * that other asynchronous scans started after this one won't affect the 1750 * ordering of the discovered devices. 1751 */ 1752 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 1753 { 1754 struct async_scan_data *data; 1755 unsigned long flags; 1756 1757 if (strncmp(scsi_scan_type, "sync", 4) == 0) 1758 return NULL; 1759 1760 if (shost->async_scan) { 1761 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1762 dump_stack(); 1763 return NULL; 1764 } 1765 1766 data = kmalloc(sizeof(*data), GFP_KERNEL); 1767 if (!data) 1768 goto err; 1769 data->shost = scsi_host_get(shost); 1770 if (!data->shost) 1771 goto err; 1772 init_completion(&data->prev_finished); 1773 1774 mutex_lock(&shost->scan_mutex); 1775 spin_lock_irqsave(shost->host_lock, flags); 1776 shost->async_scan = 1; 1777 spin_unlock_irqrestore(shost->host_lock, flags); 1778 mutex_unlock(&shost->scan_mutex); 1779 1780 spin_lock(&async_scan_lock); 1781 if (list_empty(&scanning_hosts)) 1782 complete(&data->prev_finished); 1783 list_add_tail(&data->list, &scanning_hosts); 1784 spin_unlock(&async_scan_lock); 1785 1786 return data; 1787 1788 err: 1789 kfree(data); 1790 return NULL; 1791 } 1792 1793 /** 1794 * scsi_finish_async_scan - asynchronous scan has finished 1795 * @data: cookie returned from earlier call to scsi_prep_async_scan() 1796 * 1797 * All the devices currently attached to this host have been found. 1798 * This function announces all the devices it has found to the rest 1799 * of the system. 1800 */ 1801 static void scsi_finish_async_scan(struct async_scan_data *data) 1802 { 1803 struct Scsi_Host *shost; 1804 unsigned long flags; 1805 1806 if (!data) 1807 return; 1808 1809 shost = data->shost; 1810 1811 mutex_lock(&shost->scan_mutex); 1812 1813 if (!shost->async_scan) { 1814 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1815 dump_stack(); 1816 mutex_unlock(&shost->scan_mutex); 1817 return; 1818 } 1819 1820 wait_for_completion(&data->prev_finished); 1821 1822 scsi_sysfs_add_devices(shost); 1823 1824 spin_lock_irqsave(shost->host_lock, flags); 1825 shost->async_scan = 0; 1826 spin_unlock_irqrestore(shost->host_lock, flags); 1827 1828 mutex_unlock(&shost->scan_mutex); 1829 1830 spin_lock(&async_scan_lock); 1831 list_del(&data->list); 1832 if (!list_empty(&scanning_hosts)) { 1833 struct async_scan_data *next = list_entry(scanning_hosts.next, 1834 struct async_scan_data, list); 1835 complete(&next->prev_finished); 1836 } 1837 spin_unlock(&async_scan_lock); 1838 1839 scsi_autopm_put_host(shost); 1840 scsi_host_put(shost); 1841 kfree(data); 1842 } 1843 1844 static void do_scsi_scan_host(struct Scsi_Host *shost) 1845 { 1846 if (shost->hostt->scan_finished) { 1847 unsigned long start = jiffies; 1848 if (shost->hostt->scan_start) 1849 shost->hostt->scan_start(shost); 1850 1851 while (!shost->hostt->scan_finished(shost, jiffies - start)) 1852 msleep(10); 1853 } else { 1854 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, 1855 SCAN_WILD_CARD, 0); 1856 } 1857 } 1858 1859 static void do_scan_async(void *_data, async_cookie_t c) 1860 { 1861 struct async_scan_data *data = _data; 1862 struct Scsi_Host *shost = data->shost; 1863 1864 do_scsi_scan_host(shost); 1865 scsi_finish_async_scan(data); 1866 } 1867 1868 /** 1869 * scsi_scan_host - scan the given adapter 1870 * @shost: adapter to scan 1871 **/ 1872 void scsi_scan_host(struct Scsi_Host *shost) 1873 { 1874 struct async_scan_data *data; 1875 1876 if (strncmp(scsi_scan_type, "none", 4) == 0) 1877 return; 1878 if (scsi_autopm_get_host(shost) < 0) 1879 return; 1880 1881 data = scsi_prep_async_scan(shost); 1882 if (!data) { 1883 do_scsi_scan_host(shost); 1884 scsi_autopm_put_host(shost); 1885 return; 1886 } 1887 1888 /* register with the async subsystem so wait_for_device_probe() 1889 * will flush this work 1890 */ 1891 async_schedule(do_scan_async, data); 1892 1893 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */ 1894 } 1895 EXPORT_SYMBOL(scsi_scan_host); 1896 1897 void scsi_forget_host(struct Scsi_Host *shost) 1898 { 1899 struct scsi_device *sdev; 1900 unsigned long flags; 1901 1902 restart: 1903 spin_lock_irqsave(shost->host_lock, flags); 1904 list_for_each_entry(sdev, &shost->__devices, siblings) { 1905 if (sdev->sdev_state == SDEV_DEL) 1906 continue; 1907 spin_unlock_irqrestore(shost->host_lock, flags); 1908 __scsi_remove_device(sdev); 1909 goto restart; 1910 } 1911 spin_unlock_irqrestore(shost->host_lock, flags); 1912 } 1913 1914 /** 1915 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself 1916 * @shost: Host that needs a scsi_device 1917 * 1918 * Lock status: None assumed. 1919 * 1920 * Returns: The scsi_device or NULL 1921 * 1922 * Notes: 1923 * Attach a single scsi_device to the Scsi_Host - this should 1924 * be made to look like a "pseudo-device" that points to the 1925 * HA itself. 1926 * 1927 * Note - this device is not accessible from any high-level 1928 * drivers (including generics), which is probably not 1929 * optimal. We can add hooks later to attach. 1930 */ 1931 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) 1932 { 1933 struct scsi_device *sdev = NULL; 1934 struct scsi_target *starget; 1935 1936 mutex_lock(&shost->scan_mutex); 1937 if (!scsi_host_scan_allowed(shost)) 1938 goto out; 1939 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); 1940 if (!starget) 1941 goto out; 1942 1943 sdev = scsi_alloc_sdev(starget, 0, NULL); 1944 if (sdev) 1945 sdev->borken = 0; 1946 else 1947 scsi_target_reap(starget); 1948 put_device(&starget->dev); 1949 out: 1950 mutex_unlock(&shost->scan_mutex); 1951 return sdev; 1952 } 1953 EXPORT_SYMBOL(scsi_get_host_dev); 1954 1955 /** 1956 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself 1957 * @sdev: Host device to be freed 1958 * 1959 * Lock status: None assumed. 1960 * 1961 * Returns: Nothing 1962 */ 1963 void scsi_free_host_dev(struct scsi_device *sdev) 1964 { 1965 BUG_ON(sdev->id != sdev->host->this_id); 1966 1967 __scsi_remove_device(sdev); 1968 } 1969 EXPORT_SYMBOL(scsi_free_host_dev); 1970 1971