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_dh.h> 47 #include <scsi/scsi_eh.h> 48 49 #include "scsi_priv.h" 50 #include "scsi_logging.h" 51 52 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \ 53 " SCSI scanning, some SCSI devices might not be configured\n" 54 55 /* 56 * Default timeout 57 */ 58 #define SCSI_TIMEOUT (2*HZ) 59 #define SCSI_REPORT_LUNS_TIMEOUT (30*HZ) 60 61 /* 62 * Prefix values for the SCSI id's (stored in sysfs name field) 63 */ 64 #define SCSI_UID_SER_NUM 'S' 65 #define SCSI_UID_UNKNOWN 'Z' 66 67 /* 68 * Return values of some of the scanning functions. 69 * 70 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this 71 * includes allocation or general failures preventing IO from being sent. 72 * 73 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available 74 * on the given LUN. 75 * 76 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a 77 * given LUN. 78 */ 79 #define SCSI_SCAN_NO_RESPONSE 0 80 #define SCSI_SCAN_TARGET_PRESENT 1 81 #define SCSI_SCAN_LUN_PRESENT 2 82 83 static const char *scsi_null_device_strs = "nullnullnullnull"; 84 85 #define MAX_SCSI_LUNS 512 86 87 static u64 max_scsi_luns = MAX_SCSI_LUNS; 88 89 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR); 90 MODULE_PARM_DESC(max_luns, 91 "last scsi LUN (should be between 1 and 2^64-1)"); 92 93 #ifdef CONFIG_SCSI_SCAN_ASYNC 94 #define SCSI_SCAN_TYPE_DEFAULT "async" 95 #else 96 #define SCSI_SCAN_TYPE_DEFAULT "sync" 97 #endif 98 99 char scsi_scan_type[7] = SCSI_SCAN_TYPE_DEFAULT; 100 101 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), 102 S_IRUGO|S_IWUSR); 103 MODULE_PARM_DESC(scan, "sync, async, manual, or none. " 104 "Setting to 'manual' disables automatic scanning, but allows " 105 "for manual device scan via the 'scan' sysfs attribute."); 106 107 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18; 108 109 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); 110 MODULE_PARM_DESC(inq_timeout, 111 "Timeout (in seconds) waiting for devices to answer INQUIRY." 112 " Default is 20. Some devices may need more; most need less."); 113 114 /* This lock protects only this list */ 115 static DEFINE_SPINLOCK(async_scan_lock); 116 static LIST_HEAD(scanning_hosts); 117 118 struct async_scan_data { 119 struct list_head list; 120 struct Scsi_Host *shost; 121 struct completion prev_finished; 122 }; 123 124 /** 125 * scsi_complete_async_scans - Wait for asynchronous scans to complete 126 * 127 * When this function returns, any host which started scanning before 128 * this function was called will have finished its scan. Hosts which 129 * started scanning after this function was called may or may not have 130 * finished. 131 */ 132 int scsi_complete_async_scans(void) 133 { 134 struct async_scan_data *data; 135 136 do { 137 if (list_empty(&scanning_hosts)) 138 return 0; 139 /* If we can't get memory immediately, that's OK. Just 140 * sleep a little. Even if we never get memory, the async 141 * scans will finish eventually. 142 */ 143 data = kmalloc(sizeof(*data), GFP_KERNEL); 144 if (!data) 145 msleep(1); 146 } while (!data); 147 148 data->shost = NULL; 149 init_completion(&data->prev_finished); 150 151 spin_lock(&async_scan_lock); 152 /* Check that there's still somebody else on the list */ 153 if (list_empty(&scanning_hosts)) 154 goto done; 155 list_add_tail(&data->list, &scanning_hosts); 156 spin_unlock(&async_scan_lock); 157 158 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); 159 wait_for_completion(&data->prev_finished); 160 161 spin_lock(&async_scan_lock); 162 list_del(&data->list); 163 if (!list_empty(&scanning_hosts)) { 164 struct async_scan_data *next = list_entry(scanning_hosts.next, 165 struct async_scan_data, list); 166 complete(&next->prev_finished); 167 } 168 done: 169 spin_unlock(&async_scan_lock); 170 171 kfree(data); 172 return 0; 173 } 174 175 /** 176 * scsi_unlock_floptical - unlock device via a special MODE SENSE command 177 * @sdev: scsi device to send command to 178 * @result: area to store the result of the MODE SENSE 179 * 180 * Description: 181 * Send a vendor specific MODE SENSE (not a MODE SELECT) command. 182 * Called for BLIST_KEY devices. 183 **/ 184 static void scsi_unlock_floptical(struct scsi_device *sdev, 185 unsigned char *result) 186 { 187 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 188 189 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n"); 190 scsi_cmd[0] = MODE_SENSE; 191 scsi_cmd[1] = 0; 192 scsi_cmd[2] = 0x2e; 193 scsi_cmd[3] = 0; 194 scsi_cmd[4] = 0x2a; /* size */ 195 scsi_cmd[5] = 0; 196 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, 197 SCSI_TIMEOUT, 3, NULL); 198 } 199 200 /** 201 * scsi_alloc_sdev - allocate and setup a scsi_Device 202 * @starget: which target to allocate a &scsi_device for 203 * @lun: which lun 204 * @hostdata: usually NULL and set by ->slave_alloc instead 205 * 206 * Description: 207 * Allocate, initialize for io, and return a pointer to a scsi_Device. 208 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and 209 * adds scsi_Device to the appropriate list. 210 * 211 * Return value: 212 * scsi_Device pointer, or NULL on failure. 213 **/ 214 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, 215 u64 lun, void *hostdata) 216 { 217 struct scsi_device *sdev; 218 int display_failure_msg = 1, ret; 219 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 220 221 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, 222 GFP_ATOMIC); 223 if (!sdev) 224 goto out; 225 226 sdev->vendor = scsi_null_device_strs; 227 sdev->model = scsi_null_device_strs; 228 sdev->rev = scsi_null_device_strs; 229 sdev->host = shost; 230 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD; 231 sdev->id = starget->id; 232 sdev->lun = lun; 233 sdev->channel = starget->channel; 234 sdev->sdev_state = SDEV_CREATED; 235 INIT_LIST_HEAD(&sdev->siblings); 236 INIT_LIST_HEAD(&sdev->same_target_siblings); 237 INIT_LIST_HEAD(&sdev->cmd_list); 238 INIT_LIST_HEAD(&sdev->starved_entry); 239 INIT_LIST_HEAD(&sdev->event_list); 240 spin_lock_init(&sdev->list_lock); 241 mutex_init(&sdev->inquiry_mutex); 242 INIT_WORK(&sdev->event_work, scsi_evt_thread); 243 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue); 244 245 sdev->sdev_gendev.parent = get_device(&starget->dev); 246 sdev->sdev_target = starget; 247 248 /* usually NULL and set by ->slave_alloc instead */ 249 sdev->hostdata = hostdata; 250 251 /* if the device needs this changing, it may do so in the 252 * slave_configure function */ 253 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; 254 255 /* 256 * Some low level driver could use device->type 257 */ 258 sdev->type = -1; 259 260 /* 261 * Assume that the device will have handshaking problems, 262 * and then fix this field later if it turns out it 263 * doesn't 264 */ 265 sdev->borken = 1; 266 267 if (shost_use_blk_mq(shost)) 268 sdev->request_queue = scsi_mq_alloc_queue(sdev); 269 else 270 sdev->request_queue = scsi_alloc_queue(sdev); 271 if (!sdev->request_queue) { 272 /* release fn is set up in scsi_sysfs_device_initialise, so 273 * have to free and put manually here */ 274 put_device(&starget->dev); 275 kfree(sdev); 276 goto out; 277 } 278 WARN_ON_ONCE(!blk_get_queue(sdev->request_queue)); 279 sdev->request_queue->queuedata = sdev; 280 281 if (!shost_use_blk_mq(sdev->host)) { 282 blk_queue_init_tags(sdev->request_queue, 283 sdev->host->cmd_per_lun, shost->bqt, 284 shost->hostt->tag_alloc_policy); 285 } 286 scsi_change_queue_depth(sdev, sdev->host->cmd_per_lun ? 287 sdev->host->cmd_per_lun : 1); 288 289 scsi_sysfs_device_initialize(sdev); 290 291 if (shost->hostt->slave_alloc) { 292 ret = shost->hostt->slave_alloc(sdev); 293 if (ret) { 294 /* 295 * if LLDD reports slave not present, don't clutter 296 * console with alloc failure messages 297 */ 298 if (ret == -ENXIO) 299 display_failure_msg = 0; 300 goto out_device_destroy; 301 } 302 } 303 304 return sdev; 305 306 out_device_destroy: 307 __scsi_remove_device(sdev); 308 out: 309 if (display_failure_msg) 310 printk(ALLOC_FAILURE_MSG, __func__); 311 return NULL; 312 } 313 314 static void scsi_target_destroy(struct scsi_target *starget) 315 { 316 struct device *dev = &starget->dev; 317 struct Scsi_Host *shost = dev_to_shost(dev->parent); 318 unsigned long flags; 319 320 BUG_ON(starget->state == STARGET_DEL); 321 starget->state = STARGET_DEL; 322 transport_destroy_device(dev); 323 spin_lock_irqsave(shost->host_lock, flags); 324 if (shost->hostt->target_destroy) 325 shost->hostt->target_destroy(starget); 326 list_del_init(&starget->siblings); 327 spin_unlock_irqrestore(shost->host_lock, flags); 328 put_device(dev); 329 } 330 331 static void scsi_target_dev_release(struct device *dev) 332 { 333 struct device *parent = dev->parent; 334 struct scsi_target *starget = to_scsi_target(dev); 335 336 kfree(starget); 337 put_device(parent); 338 } 339 340 static struct device_type scsi_target_type = { 341 .name = "scsi_target", 342 .release = scsi_target_dev_release, 343 }; 344 345 int scsi_is_target_device(const struct device *dev) 346 { 347 return dev->type == &scsi_target_type; 348 } 349 EXPORT_SYMBOL(scsi_is_target_device); 350 351 static struct scsi_target *__scsi_find_target(struct device *parent, 352 int channel, uint id) 353 { 354 struct scsi_target *starget, *found_starget = NULL; 355 struct Scsi_Host *shost = dev_to_shost(parent); 356 /* 357 * Search for an existing target for this sdev. 358 */ 359 list_for_each_entry(starget, &shost->__targets, siblings) { 360 if (starget->id == id && 361 starget->channel == channel) { 362 found_starget = starget; 363 break; 364 } 365 } 366 if (found_starget) 367 get_device(&found_starget->dev); 368 369 return found_starget; 370 } 371 372 /** 373 * scsi_target_reap_ref_release - remove target from visibility 374 * @kref: the reap_ref in the target being released 375 * 376 * Called on last put of reap_ref, which is the indication that no device 377 * under this target is visible anymore, so render the target invisible in 378 * sysfs. Note: we have to be in user context here because the target reaps 379 * should be done in places where the scsi device visibility is being removed. 380 */ 381 static void scsi_target_reap_ref_release(struct kref *kref) 382 { 383 struct scsi_target *starget 384 = container_of(kref, struct scsi_target, reap_ref); 385 386 /* 387 * if we get here and the target is still in the CREATED state that 388 * means it was allocated but never made visible (because a scan 389 * turned up no LUNs), so don't call device_del() on it. 390 */ 391 if (starget->state != STARGET_CREATED) { 392 transport_remove_device(&starget->dev); 393 device_del(&starget->dev); 394 } 395 scsi_target_destroy(starget); 396 } 397 398 static void scsi_target_reap_ref_put(struct scsi_target *starget) 399 { 400 kref_put(&starget->reap_ref, scsi_target_reap_ref_release); 401 } 402 403 /** 404 * scsi_alloc_target - allocate a new or find an existing target 405 * @parent: parent of the target (need not be a scsi host) 406 * @channel: target channel number (zero if no channels) 407 * @id: target id number 408 * 409 * Return an existing target if one exists, provided it hasn't already 410 * gone into STARGET_DEL state, otherwise allocate a new target. 411 * 412 * The target is returned with an incremented reference, so the caller 413 * is responsible for both reaping and doing a last put 414 */ 415 static struct scsi_target *scsi_alloc_target(struct device *parent, 416 int channel, uint id) 417 { 418 struct Scsi_Host *shost = dev_to_shost(parent); 419 struct device *dev = NULL; 420 unsigned long flags; 421 const int size = sizeof(struct scsi_target) 422 + shost->transportt->target_size; 423 struct scsi_target *starget; 424 struct scsi_target *found_target; 425 int error, ref_got; 426 427 starget = kzalloc(size, GFP_KERNEL); 428 if (!starget) { 429 printk(KERN_ERR "%s: allocation failure\n", __func__); 430 return NULL; 431 } 432 dev = &starget->dev; 433 device_initialize(dev); 434 kref_init(&starget->reap_ref); 435 dev->parent = get_device(parent); 436 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); 437 dev->bus = &scsi_bus_type; 438 dev->type = &scsi_target_type; 439 starget->id = id; 440 starget->channel = channel; 441 starget->can_queue = 0; 442 INIT_LIST_HEAD(&starget->siblings); 443 INIT_LIST_HEAD(&starget->devices); 444 starget->state = STARGET_CREATED; 445 starget->scsi_level = SCSI_2; 446 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; 447 retry: 448 spin_lock_irqsave(shost->host_lock, flags); 449 450 found_target = __scsi_find_target(parent, channel, id); 451 if (found_target) 452 goto found; 453 454 list_add_tail(&starget->siblings, &shost->__targets); 455 spin_unlock_irqrestore(shost->host_lock, flags); 456 /* allocate and add */ 457 transport_setup_device(dev); 458 if (shost->hostt->target_alloc) { 459 error = shost->hostt->target_alloc(starget); 460 461 if(error) { 462 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error); 463 /* don't want scsi_target_reap to do the final 464 * put because it will be under the host lock */ 465 scsi_target_destroy(starget); 466 return NULL; 467 } 468 } 469 get_device(dev); 470 471 return starget; 472 473 found: 474 /* 475 * release routine already fired if kref is zero, so if we can still 476 * take the reference, the target must be alive. If we can't, it must 477 * be dying and we need to wait for a new target 478 */ 479 ref_got = kref_get_unless_zero(&found_target->reap_ref); 480 481 spin_unlock_irqrestore(shost->host_lock, flags); 482 if (ref_got) { 483 put_device(dev); 484 return found_target; 485 } 486 /* 487 * Unfortunately, we found a dying target; need to wait until it's 488 * dead before we can get a new one. There is an anomaly here. We 489 * *should* call scsi_target_reap() to balance the kref_get() of the 490 * reap_ref above. However, since the target being released, it's 491 * already invisible and the reap_ref is irrelevant. If we call 492 * scsi_target_reap() we might spuriously do another device_del() on 493 * an already invisible target. 494 */ 495 put_device(&found_target->dev); 496 /* 497 * length of time is irrelevant here, we just want to yield the CPU 498 * for a tick to avoid busy waiting for the target to die. 499 */ 500 msleep(1); 501 goto retry; 502 } 503 504 /** 505 * scsi_target_reap - check to see if target is in use and destroy if not 506 * @starget: target to be checked 507 * 508 * This is used after removing a LUN or doing a last put of the target 509 * it checks atomically that nothing is using the target and removes 510 * it if so. 511 */ 512 void scsi_target_reap(struct scsi_target *starget) 513 { 514 /* 515 * serious problem if this triggers: STARGET_DEL is only set in the if 516 * the reap_ref drops to zero, so we're trying to do another final put 517 * on an already released kref 518 */ 519 BUG_ON(starget->state == STARGET_DEL); 520 scsi_target_reap_ref_put(starget); 521 } 522 523 /** 524 * scsi_sanitize_inquiry_string - remove non-graphical chars from an 525 * 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 void scsi_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 EXPORT_SYMBOL(scsi_sanitize_inquiry_string); 550 551 /** 552 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY 553 * @sdev: scsi_device to probe 554 * @inq_result: area to store the INQUIRY result 555 * @result_len: len of inq_result 556 * @bflags: store any bflags found here 557 * 558 * Description: 559 * Probe the lun associated with @req using a standard SCSI INQUIRY; 560 * 561 * If the INQUIRY is successful, zero is returned and the 562 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length 563 * are copied to the scsi_device any flags value is stored in *@bflags. 564 **/ 565 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, 566 int result_len, int *bflags) 567 { 568 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 569 int first_inquiry_len, try_inquiry_len, next_inquiry_len; 570 int response_len = 0; 571 int pass, count, result; 572 struct scsi_sense_hdr sshdr; 573 574 *bflags = 0; 575 576 /* Perform up to 3 passes. The first pass uses a conservative 577 * transfer length of 36 unless sdev->inquiry_len specifies a 578 * different value. */ 579 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; 580 try_inquiry_len = first_inquiry_len; 581 pass = 1; 582 583 next_pass: 584 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 585 "scsi scan: INQUIRY pass %d length %d\n", 586 pass, try_inquiry_len)); 587 588 /* Each pass gets up to three chances to ignore Unit Attention */ 589 for (count = 0; count < 3; ++count) { 590 int resid; 591 592 memset(scsi_cmd, 0, 6); 593 scsi_cmd[0] = INQUIRY; 594 scsi_cmd[4] = (unsigned char) try_inquiry_len; 595 596 memset(inq_result, 0, try_inquiry_len); 597 598 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 599 inq_result, try_inquiry_len, &sshdr, 600 HZ / 2 + HZ * scsi_inq_timeout, 3, 601 &resid); 602 603 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 604 "scsi scan: INQUIRY %s with code 0x%x\n", 605 result ? "failed" : "successful", result)); 606 607 if (result) { 608 /* 609 * not-ready to ready transition [asc/ascq=0x28/0x0] 610 * or power-on, reset [asc/ascq=0x29/0x0], continue. 611 * INQUIRY should not yield UNIT_ATTENTION 612 * but many buggy devices do so anyway. 613 */ 614 if ((driver_byte(result) & DRIVER_SENSE) && 615 scsi_sense_valid(&sshdr)) { 616 if ((sshdr.sense_key == UNIT_ATTENTION) && 617 ((sshdr.asc == 0x28) || 618 (sshdr.asc == 0x29)) && 619 (sshdr.ascq == 0)) 620 continue; 621 } 622 } else { 623 /* 624 * if nothing was transferred, we try 625 * again. It's a workaround for some USB 626 * devices. 627 */ 628 if (resid == try_inquiry_len) 629 continue; 630 } 631 break; 632 } 633 634 if (result == 0) { 635 scsi_sanitize_inquiry_string(&inq_result[8], 8); 636 scsi_sanitize_inquiry_string(&inq_result[16], 16); 637 scsi_sanitize_inquiry_string(&inq_result[32], 4); 638 639 response_len = inq_result[4] + 5; 640 if (response_len > 255) 641 response_len = first_inquiry_len; /* sanity */ 642 643 /* 644 * Get any flags for this device. 645 * 646 * XXX add a bflags to scsi_device, and replace the 647 * corresponding bit fields in scsi_device, so bflags 648 * need not be passed as an argument. 649 */ 650 *bflags = scsi_get_device_flags(sdev, &inq_result[8], 651 &inq_result[16]); 652 653 /* When the first pass succeeds we gain information about 654 * what larger transfer lengths might work. */ 655 if (pass == 1) { 656 if (BLIST_INQUIRY_36 & *bflags) 657 next_inquiry_len = 36; 658 else if (BLIST_INQUIRY_58 & *bflags) 659 next_inquiry_len = 58; 660 else if (sdev->inquiry_len) 661 next_inquiry_len = sdev->inquiry_len; 662 else 663 next_inquiry_len = response_len; 664 665 /* If more data is available perform the second pass */ 666 if (next_inquiry_len > try_inquiry_len) { 667 try_inquiry_len = next_inquiry_len; 668 pass = 2; 669 goto next_pass; 670 } 671 } 672 673 } else if (pass == 2) { 674 sdev_printk(KERN_INFO, sdev, 675 "scsi scan: %d byte inquiry failed. " 676 "Consider BLIST_INQUIRY_36 for this device\n", 677 try_inquiry_len); 678 679 /* If this pass failed, the third pass goes back and transfers 680 * the same amount as we successfully got in the first pass. */ 681 try_inquiry_len = first_inquiry_len; 682 pass = 3; 683 goto next_pass; 684 } 685 686 /* If the last transfer attempt got an error, assume the 687 * peripheral doesn't exist or is dead. */ 688 if (result) 689 return -EIO; 690 691 /* Don't report any more data than the device says is valid */ 692 sdev->inquiry_len = min(try_inquiry_len, response_len); 693 694 /* 695 * XXX Abort if the response length is less than 36? If less than 696 * 32, the lookup of the device flags (above) could be invalid, 697 * and it would be possible to take an incorrect action - we do 698 * not want to hang because of a short INQUIRY. On the flip side, 699 * if the device is spun down or becoming ready (and so it gives a 700 * short INQUIRY), an abort here prevents any further use of the 701 * device, including spin up. 702 * 703 * On the whole, the best approach seems to be to assume the first 704 * 36 bytes are valid no matter what the device says. That's 705 * better than copying < 36 bytes to the inquiry-result buffer 706 * and displaying garbage for the Vendor, Product, or Revision 707 * strings. 708 */ 709 if (sdev->inquiry_len < 36) { 710 if (!sdev->host->short_inquiry) { 711 shost_printk(KERN_INFO, sdev->host, 712 "scsi scan: INQUIRY result too short (%d)," 713 " using 36\n", sdev->inquiry_len); 714 sdev->host->short_inquiry = 1; 715 } 716 sdev->inquiry_len = 36; 717 } 718 719 /* 720 * Related to the above issue: 721 * 722 * XXX Devices (disk or all?) should be sent a TEST UNIT READY, 723 * and if not ready, sent a START_STOP to start (maybe spin up) and 724 * then send the INQUIRY again, since the INQUIRY can change after 725 * a device is initialized. 726 * 727 * Ideally, start a device if explicitly asked to do so. This 728 * assumes that a device is spun up on power on, spun down on 729 * request, and then spun up on request. 730 */ 731 732 /* 733 * The scanning code needs to know the scsi_level, even if no 734 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so 735 * non-zero LUNs can be scanned. 736 */ 737 sdev->scsi_level = inq_result[2] & 0x07; 738 if (sdev->scsi_level >= 2 || 739 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) 740 sdev->scsi_level++; 741 sdev->sdev_target->scsi_level = sdev->scsi_level; 742 743 /* 744 * If SCSI-2 or lower, and if the transport requires it, 745 * store the LUN value in CDB[1]. 746 */ 747 sdev->lun_in_cdb = 0; 748 if (sdev->scsi_level <= SCSI_2 && 749 sdev->scsi_level != SCSI_UNKNOWN && 750 !sdev->host->no_scsi2_lun_in_cdb) 751 sdev->lun_in_cdb = 1; 752 753 return 0; 754 } 755 756 /** 757 * scsi_add_lun - allocate and fully initialze a scsi_device 758 * @sdev: holds information to be stored in the new scsi_device 759 * @inq_result: holds the result of a previous INQUIRY to the LUN 760 * @bflags: black/white list flag 761 * @async: 1 if this device is being scanned asynchronously 762 * 763 * Description: 764 * Initialize the scsi_device @sdev. Optionally set fields based 765 * on values in *@bflags. 766 * 767 * Return: 768 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 769 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 770 **/ 771 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, 772 int *bflags, int async) 773 { 774 int ret; 775 776 /* 777 * XXX do not save the inquiry, since it can change underneath us, 778 * save just vendor/model/rev. 779 * 780 * Rather than save it and have an ioctl that retrieves the saved 781 * value, have an ioctl that executes the same INQUIRY code used 782 * in scsi_probe_lun, let user level programs doing INQUIRY 783 * scanning run at their own risk, or supply a user level program 784 * that can correctly scan. 785 */ 786 787 /* 788 * Copy at least 36 bytes of INQUIRY data, so that we don't 789 * dereference unallocated memory when accessing the Vendor, 790 * Product, and Revision strings. Badly behaved devices may set 791 * the INQUIRY Additional Length byte to a small value, indicating 792 * these strings are invalid, but often they contain plausible data 793 * nonetheless. It doesn't matter if the device sent < 36 bytes 794 * total, since scsi_probe_lun() initializes inq_result with 0s. 795 */ 796 sdev->inquiry = kmemdup(inq_result, 797 max_t(size_t, sdev->inquiry_len, 36), 798 GFP_ATOMIC); 799 if (sdev->inquiry == NULL) 800 return SCSI_SCAN_NO_RESPONSE; 801 802 sdev->vendor = (char *) (sdev->inquiry + 8); 803 sdev->model = (char *) (sdev->inquiry + 16); 804 sdev->rev = (char *) (sdev->inquiry + 32); 805 806 if (strncmp(sdev->vendor, "ATA ", 8) == 0) { 807 /* 808 * sata emulation layer device. This is a hack to work around 809 * the SATL power management specifications which state that 810 * when the SATL detects the device has gone into standby 811 * mode, it shall respond with NOT READY. 812 */ 813 sdev->allow_restart = 1; 814 } 815 816 if (*bflags & BLIST_ISROM) { 817 sdev->type = TYPE_ROM; 818 sdev->removable = 1; 819 } else { 820 sdev->type = (inq_result[0] & 0x1f); 821 sdev->removable = (inq_result[1] & 0x80) >> 7; 822 823 /* 824 * some devices may respond with wrong type for 825 * well-known logical units. Force well-known type 826 * to enumerate them correctly. 827 */ 828 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) { 829 sdev_printk(KERN_WARNING, sdev, 830 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n", 831 __func__, sdev->type, (unsigned int)sdev->lun); 832 sdev->type = TYPE_WLUN; 833 } 834 835 } 836 837 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { 838 /* RBC and MMC devices can return SCSI-3 compliance and yet 839 * still not support REPORT LUNS, so make them act as 840 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is 841 * specifically set */ 842 if ((*bflags & BLIST_REPORTLUN2) == 0) 843 *bflags |= BLIST_NOREPORTLUN; 844 } 845 846 /* 847 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI 848 * spec says: The device server is capable of supporting the 849 * specified peripheral device type on this logical unit. However, 850 * the physical device is not currently connected to this logical 851 * unit. 852 * 853 * The above is vague, as it implies that we could treat 001 and 854 * 011 the same. Stay compatible with previous code, and create a 855 * scsi_device for a PQ of 1 856 * 857 * Don't set the device offline here; rather let the upper 858 * level drivers eval the PQ to decide whether they should 859 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. 860 */ 861 862 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; 863 sdev->lockable = sdev->removable; 864 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); 865 866 if (sdev->scsi_level >= SCSI_3 || 867 (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) 868 sdev->ppr = 1; 869 if (inq_result[7] & 0x60) 870 sdev->wdtr = 1; 871 if (inq_result[7] & 0x10) 872 sdev->sdtr = 1; 873 874 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " 875 "ANSI: %d%s\n", scsi_device_type(sdev->type), 876 sdev->vendor, sdev->model, sdev->rev, 877 sdev->inq_periph_qual, inq_result[2] & 0x07, 878 (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); 879 880 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && 881 !(*bflags & BLIST_NOTQ)) { 882 sdev->tagged_supported = 1; 883 sdev->simple_tags = 1; 884 } 885 886 /* 887 * Some devices (Texel CD ROM drives) have handshaking problems 888 * when used with the Seagate controllers. borken is initialized 889 * to 1, and then set it to 0 here. 890 */ 891 if ((*bflags & BLIST_BORKEN) == 0) 892 sdev->borken = 0; 893 894 if (*bflags & BLIST_NO_ULD_ATTACH) 895 sdev->no_uld_attach = 1; 896 897 /* 898 * Apparently some really broken devices (contrary to the SCSI 899 * standards) need to be selected without asserting ATN 900 */ 901 if (*bflags & BLIST_SELECT_NO_ATN) 902 sdev->select_no_atn = 1; 903 904 /* 905 * Maximum 512 sector transfer length 906 * broken RA4x00 Compaq Disk Array 907 */ 908 if (*bflags & BLIST_MAX_512) 909 blk_queue_max_hw_sectors(sdev->request_queue, 512); 910 /* 911 * Max 1024 sector transfer length for targets that report incorrect 912 * max/optimal lengths and relied on the old block layer safe default 913 */ 914 else if (*bflags & BLIST_MAX_1024) 915 blk_queue_max_hw_sectors(sdev->request_queue, 1024); 916 917 /* 918 * Some devices may not want to have a start command automatically 919 * issued when a device is added. 920 */ 921 if (*bflags & BLIST_NOSTARTONADD) 922 sdev->no_start_on_add = 1; 923 924 if (*bflags & BLIST_SINGLELUN) 925 scsi_target(sdev)->single_lun = 1; 926 927 sdev->use_10_for_rw = 1; 928 929 if (*bflags & BLIST_MS_SKIP_PAGE_08) 930 sdev->skip_ms_page_8 = 1; 931 932 if (*bflags & BLIST_MS_SKIP_PAGE_3F) 933 sdev->skip_ms_page_3f = 1; 934 935 if (*bflags & BLIST_USE_10_BYTE_MS) 936 sdev->use_10_for_ms = 1; 937 938 /* some devices don't like REPORT SUPPORTED OPERATION CODES 939 * and will simply timeout causing sd_mod init to take a very 940 * very long time */ 941 if (*bflags & BLIST_NO_RSOC) 942 sdev->no_report_opcodes = 1; 943 944 /* set the device running here so that slave configure 945 * may do I/O */ 946 ret = scsi_device_set_state(sdev, SDEV_RUNNING); 947 if (ret) { 948 ret = scsi_device_set_state(sdev, SDEV_BLOCK); 949 950 if (ret) { 951 sdev_printk(KERN_ERR, sdev, 952 "in wrong state %s to complete scan\n", 953 scsi_device_state_name(sdev->sdev_state)); 954 return SCSI_SCAN_NO_RESPONSE; 955 } 956 } 957 958 if (*bflags & BLIST_MS_192_BYTES_FOR_3F) 959 sdev->use_192_bytes_for_3f = 1; 960 961 if (*bflags & BLIST_NOT_LOCKABLE) 962 sdev->lockable = 0; 963 964 if (*bflags & BLIST_RETRY_HWERROR) 965 sdev->retry_hwerror = 1; 966 967 if (*bflags & BLIST_NO_DIF) 968 sdev->no_dif = 1; 969 970 if (*bflags & BLIST_SYNC_ALUA) 971 sdev->synchronous_alua = 1; 972 973 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; 974 975 if (*bflags & BLIST_TRY_VPD_PAGES) 976 sdev->try_vpd_pages = 1; 977 else if (*bflags & BLIST_SKIP_VPD_PAGES) 978 sdev->skip_vpd_pages = 1; 979 980 transport_configure_device(&sdev->sdev_gendev); 981 982 if (sdev->host->hostt->slave_configure) { 983 ret = sdev->host->hostt->slave_configure(sdev); 984 if (ret) { 985 /* 986 * if LLDD reports slave not present, don't clutter 987 * console with alloc failure messages 988 */ 989 if (ret != -ENXIO) { 990 sdev_printk(KERN_ERR, sdev, 991 "failed to configure device\n"); 992 } 993 return SCSI_SCAN_NO_RESPONSE; 994 } 995 } 996 997 if (sdev->scsi_level >= SCSI_3) 998 scsi_attach_vpd(sdev); 999 1000 sdev->max_queue_depth = sdev->queue_depth; 1001 1002 /* 1003 * Ok, the device is now all set up, we can 1004 * register it and tell the rest of the kernel 1005 * about it. 1006 */ 1007 if (!async && scsi_sysfs_add_sdev(sdev) != 0) 1008 return SCSI_SCAN_NO_RESPONSE; 1009 1010 return SCSI_SCAN_LUN_PRESENT; 1011 } 1012 1013 #ifdef CONFIG_SCSI_LOGGING 1014 /** 1015 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace 1016 * @buf: Output buffer with at least end-first+1 bytes of space 1017 * @inq: Inquiry buffer (input) 1018 * @first: Offset of string into inq 1019 * @end: Index after last character in inq 1020 */ 1021 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, 1022 unsigned first, unsigned end) 1023 { 1024 unsigned term = 0, idx; 1025 1026 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { 1027 if (inq[idx+first] > ' ') { 1028 buf[idx] = inq[idx+first]; 1029 term = idx+1; 1030 } else { 1031 buf[idx] = ' '; 1032 } 1033 } 1034 buf[term] = 0; 1035 return buf; 1036 } 1037 #endif 1038 1039 /** 1040 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it 1041 * @starget: pointer to target device structure 1042 * @lun: LUN of target device 1043 * @bflagsp: store bflags here if not NULL 1044 * @sdevp: probe the LUN corresponding to this scsi_device 1045 * @rescan: if not equal to SCSI_SCAN_INITIAL skip some code only 1046 * needed on first scan 1047 * @hostdata: passed to scsi_alloc_sdev() 1048 * 1049 * Description: 1050 * Call scsi_probe_lun, if a LUN with an attached device is found, 1051 * allocate and set it up by calling scsi_add_lun. 1052 * 1053 * Return: 1054 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 1055 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is 1056 * attached at the LUN 1057 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 1058 **/ 1059 static int scsi_probe_and_add_lun(struct scsi_target *starget, 1060 u64 lun, int *bflagsp, 1061 struct scsi_device **sdevp, 1062 enum scsi_scan_mode rescan, 1063 void *hostdata) 1064 { 1065 struct scsi_device *sdev; 1066 unsigned char *result; 1067 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256; 1068 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1069 1070 /* 1071 * The rescan flag is used as an optimization, the first scan of a 1072 * host adapter calls into here with rescan == 0. 1073 */ 1074 sdev = scsi_device_lookup_by_target(starget, lun); 1075 if (sdev) { 1076 if (rescan != SCSI_SCAN_INITIAL || !scsi_device_created(sdev)) { 1077 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1078 "scsi scan: device exists on %s\n", 1079 dev_name(&sdev->sdev_gendev))); 1080 if (sdevp) 1081 *sdevp = sdev; 1082 else 1083 scsi_device_put(sdev); 1084 1085 if (bflagsp) 1086 *bflagsp = scsi_get_device_flags(sdev, 1087 sdev->vendor, 1088 sdev->model); 1089 return SCSI_SCAN_LUN_PRESENT; 1090 } 1091 scsi_device_put(sdev); 1092 } else 1093 sdev = scsi_alloc_sdev(starget, lun, hostdata); 1094 if (!sdev) 1095 goto out; 1096 1097 result = kmalloc(result_len, GFP_ATOMIC | 1098 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0)); 1099 if (!result) 1100 goto out_free_sdev; 1101 1102 if (scsi_probe_lun(sdev, result, result_len, &bflags)) 1103 goto out_free_result; 1104 1105 if (bflagsp) 1106 *bflagsp = bflags; 1107 /* 1108 * result contains valid SCSI INQUIRY data. 1109 */ 1110 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) { 1111 /* 1112 * For a Peripheral qualifier 3 (011b), the SCSI 1113 * spec says: The device server is not capable of 1114 * supporting a physical device on this logical 1115 * unit. 1116 * 1117 * For disks, this implies that there is no 1118 * logical disk configured at sdev->lun, but there 1119 * is a target id responding. 1120 */ 1121 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" 1122 " peripheral qualifier of 3, device not" 1123 " added\n")) 1124 if (lun == 0) { 1125 SCSI_LOG_SCAN_BUS(1, { 1126 unsigned char vend[9]; 1127 unsigned char mod[17]; 1128 1129 sdev_printk(KERN_INFO, sdev, 1130 "scsi scan: consider passing scsi_mod." 1131 "dev_flags=%s:%s:0x240 or 0x1000240\n", 1132 scsi_inq_str(vend, result, 8, 16), 1133 scsi_inq_str(mod, result, 16, 32)); 1134 }); 1135 1136 } 1137 1138 res = SCSI_SCAN_TARGET_PRESENT; 1139 goto out_free_result; 1140 } 1141 1142 /* 1143 * Some targets may set slight variations of PQ and PDT to signal 1144 * that no LUN is present, so don't add sdev in these cases. 1145 * Two specific examples are: 1146 * 1) NetApp targets: return PQ=1, PDT=0x1f 1147 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" 1148 * in the UFI 1.0 spec (we cannot rely on reserved bits). 1149 * 1150 * References: 1151 * 1) SCSI SPC-3, pp. 145-146 1152 * PQ=1: "A peripheral device having the specified peripheral 1153 * device type is not connected to this logical unit. However, the 1154 * device server is capable of supporting the specified peripheral 1155 * device type on this logical unit." 1156 * PDT=0x1f: "Unknown or no device type" 1157 * 2) USB UFI 1.0, p. 20 1158 * PDT=00h Direct-access device (floppy) 1159 * PDT=1Fh none (no FDD connected to the requested logical unit) 1160 */ 1161 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) && 1162 (result[0] & 0x1f) == 0x1f && 1163 !scsi_is_wlun(lun)) { 1164 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 1165 "scsi scan: peripheral device type" 1166 " of 31, no device added\n")); 1167 res = SCSI_SCAN_TARGET_PRESENT; 1168 goto out_free_result; 1169 } 1170 1171 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); 1172 if (res == SCSI_SCAN_LUN_PRESENT) { 1173 if (bflags & BLIST_KEY) { 1174 sdev->lockable = 0; 1175 scsi_unlock_floptical(sdev, result); 1176 } 1177 } 1178 1179 out_free_result: 1180 kfree(result); 1181 out_free_sdev: 1182 if (res == SCSI_SCAN_LUN_PRESENT) { 1183 if (sdevp) { 1184 if (scsi_device_get(sdev) == 0) { 1185 *sdevp = sdev; 1186 } else { 1187 __scsi_remove_device(sdev); 1188 res = SCSI_SCAN_NO_RESPONSE; 1189 } 1190 } 1191 } else 1192 __scsi_remove_device(sdev); 1193 out: 1194 return res; 1195 } 1196 1197 /** 1198 * scsi_sequential_lun_scan - sequentially scan a SCSI target 1199 * @starget: pointer to target structure to scan 1200 * @bflags: black/white list flag for LUN 0 1201 * @scsi_level: Which version of the standard does this device adhere to 1202 * @rescan: passed to scsi_probe_add_lun() 1203 * 1204 * Description: 1205 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been 1206 * scanned) to some maximum lun until a LUN is found with no device 1207 * attached. Use the bflags to figure out any oddities. 1208 * 1209 * Modifies sdevscan->lun. 1210 **/ 1211 static void scsi_sequential_lun_scan(struct scsi_target *starget, 1212 int bflags, int scsi_level, 1213 enum scsi_scan_mode rescan) 1214 { 1215 uint max_dev_lun; 1216 u64 sparse_lun, lun; 1217 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1218 1219 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget, 1220 "scsi scan: Sequential scan\n")); 1221 1222 max_dev_lun = min(max_scsi_luns, shost->max_lun); 1223 /* 1224 * If this device is known to support sparse multiple units, 1225 * override the other settings, and scan all of them. Normally, 1226 * SCSI-3 devices should be scanned via the REPORT LUNS. 1227 */ 1228 if (bflags & BLIST_SPARSELUN) { 1229 max_dev_lun = shost->max_lun; 1230 sparse_lun = 1; 1231 } else 1232 sparse_lun = 0; 1233 1234 /* 1235 * If less than SCSI_1_CCS, and no special lun scanning, stop 1236 * scanning; this matches 2.4 behaviour, but could just be a bug 1237 * (to continue scanning a SCSI_1_CCS device). 1238 * 1239 * This test is broken. We might not have any device on lun0 for 1240 * a sparselun device, and if that's the case then how would we 1241 * know the real scsi_level, eh? It might make sense to just not 1242 * scan any SCSI_1 device for non-0 luns, but that check would best 1243 * go into scsi_alloc_sdev() and just have it return null when asked 1244 * to alloc an sdev for lun > 0 on an already found SCSI_1 device. 1245 * 1246 if ((sdevscan->scsi_level < SCSI_1_CCS) && 1247 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) 1248 == 0)) 1249 return; 1250 */ 1251 /* 1252 * If this device is known to support multiple units, override 1253 * the other settings, and scan all of them. 1254 */ 1255 if (bflags & BLIST_FORCELUN) 1256 max_dev_lun = shost->max_lun; 1257 /* 1258 * REGAL CDC-4X: avoid hang after LUN 4 1259 */ 1260 if (bflags & BLIST_MAX5LUN) 1261 max_dev_lun = min(5U, max_dev_lun); 1262 /* 1263 * Do not scan SCSI-2 or lower device past LUN 7, unless 1264 * BLIST_LARGELUN. 1265 */ 1266 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) 1267 max_dev_lun = min(8U, max_dev_lun); 1268 1269 /* 1270 * Stop scanning at 255 unless BLIST_SCSI3LUN 1271 */ 1272 if (!(bflags & BLIST_SCSI3LUN)) 1273 max_dev_lun = min(256U, max_dev_lun); 1274 1275 /* 1276 * We have already scanned LUN 0, so start at LUN 1. Keep scanning 1277 * until we reach the max, or no LUN is found and we are not 1278 * sparse_lun. 1279 */ 1280 for (lun = 1; lun < max_dev_lun; ++lun) 1281 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, 1282 NULL) != SCSI_SCAN_LUN_PRESENT) && 1283 !sparse_lun) 1284 return; 1285 } 1286 1287 /** 1288 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results 1289 * @starget: which target 1290 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN 1291 * @rescan: nonzero if we can skip code only needed on first scan 1292 * 1293 * Description: 1294 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. 1295 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. 1296 * 1297 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 1298 * LUNs even if it's older than SCSI-3. 1299 * If BLIST_NOREPORTLUN is set, return 1 always. 1300 * If BLIST_NOLUN is set, return 0 always. 1301 * If starget->no_report_luns is set, return 1 always. 1302 * 1303 * Return: 1304 * 0: scan completed (or no memory, so further scanning is futile) 1305 * 1: could not scan with REPORT LUN 1306 **/ 1307 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags, 1308 enum scsi_scan_mode rescan) 1309 { 1310 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 1311 unsigned int length; 1312 u64 lun; 1313 unsigned int num_luns; 1314 unsigned int retries; 1315 int result; 1316 struct scsi_lun *lunp, *lun_data; 1317 struct scsi_sense_hdr sshdr; 1318 struct scsi_device *sdev; 1319 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 1320 int ret = 0; 1321 1322 /* 1323 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. 1324 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does 1325 * support more than 8 LUNs. 1326 * Don't attempt if the target doesn't support REPORT LUNS. 1327 */ 1328 if (bflags & BLIST_NOREPORTLUN) 1329 return 1; 1330 if (starget->scsi_level < SCSI_2 && 1331 starget->scsi_level != SCSI_UNKNOWN) 1332 return 1; 1333 if (starget->scsi_level < SCSI_3 && 1334 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) 1335 return 1; 1336 if (bflags & BLIST_NOLUN) 1337 return 0; 1338 if (starget->no_report_luns) 1339 return 1; 1340 1341 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { 1342 sdev = scsi_alloc_sdev(starget, 0, NULL); 1343 if (!sdev) 1344 return 0; 1345 if (scsi_device_get(sdev)) { 1346 __scsi_remove_device(sdev); 1347 return 0; 1348 } 1349 } 1350 1351 /* 1352 * Allocate enough to hold the header (the same size as one scsi_lun) 1353 * plus the number of luns we are requesting. 511 was the default 1354 * value of the now removed max_report_luns parameter. 1355 */ 1356 length = (511 + 1) * sizeof(struct scsi_lun); 1357 retry: 1358 lun_data = kmalloc(length, GFP_KERNEL | 1359 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0)); 1360 if (!lun_data) { 1361 printk(ALLOC_FAILURE_MSG, __func__); 1362 goto out; 1363 } 1364 1365 scsi_cmd[0] = REPORT_LUNS; 1366 1367 /* 1368 * bytes 1 - 5: reserved, set to zero. 1369 */ 1370 memset(&scsi_cmd[1], 0, 5); 1371 1372 /* 1373 * bytes 6 - 9: length of the command. 1374 */ 1375 put_unaligned_be32(length, &scsi_cmd[6]); 1376 1377 scsi_cmd[10] = 0; /* reserved */ 1378 scsi_cmd[11] = 0; /* control */ 1379 1380 /* 1381 * We can get a UNIT ATTENTION, for example a power on/reset, so 1382 * retry a few times (like sd.c does for TEST UNIT READY). 1383 * Experience shows some combinations of adapter/devices get at 1384 * least two power on/resets. 1385 * 1386 * Illegal requests (for devices that do not support REPORT LUNS) 1387 * should come through as a check condition, and will not generate 1388 * a retry. 1389 */ 1390 for (retries = 0; retries < 3; retries++) { 1391 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1392 "scsi scan: Sending REPORT LUNS to (try %d)\n", 1393 retries)); 1394 1395 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 1396 lun_data, length, &sshdr, 1397 SCSI_REPORT_LUNS_TIMEOUT, 3, NULL); 1398 1399 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1400 "scsi scan: REPORT LUNS" 1401 " %s (try %d) result 0x%x\n", 1402 result ? "failed" : "successful", 1403 retries, result)); 1404 if (result == 0) 1405 break; 1406 else if (scsi_sense_valid(&sshdr)) { 1407 if (sshdr.sense_key != UNIT_ATTENTION) 1408 break; 1409 } 1410 } 1411 1412 if (result) { 1413 /* 1414 * The device probably does not support a REPORT LUN command 1415 */ 1416 ret = 1; 1417 goto out_err; 1418 } 1419 1420 /* 1421 * Get the length from the first four bytes of lun_data. 1422 */ 1423 if (get_unaligned_be32(lun_data->scsi_lun) + 1424 sizeof(struct scsi_lun) > length) { 1425 length = get_unaligned_be32(lun_data->scsi_lun) + 1426 sizeof(struct scsi_lun); 1427 kfree(lun_data); 1428 goto retry; 1429 } 1430 length = get_unaligned_be32(lun_data->scsi_lun); 1431 1432 num_luns = (length / sizeof(struct scsi_lun)); 1433 1434 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1435 "scsi scan: REPORT LUN scan\n")); 1436 1437 /* 1438 * Scan the luns in lun_data. The entry at offset 0 is really 1439 * the header, so start at 1 and go up to and including num_luns. 1440 */ 1441 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { 1442 lun = scsilun_to_int(lunp); 1443 1444 if (lun > sdev->host->max_lun) { 1445 sdev_printk(KERN_WARNING, sdev, 1446 "lun%llu has a LUN larger than" 1447 " allowed by the host adapter\n", lun); 1448 } else { 1449 int res; 1450 1451 res = scsi_probe_and_add_lun(starget, 1452 lun, NULL, NULL, rescan, NULL); 1453 if (res == SCSI_SCAN_NO_RESPONSE) { 1454 /* 1455 * Got some results, but now none, abort. 1456 */ 1457 sdev_printk(KERN_ERR, sdev, 1458 "Unexpected response" 1459 " from lun %llu while scanning, scan" 1460 " aborted\n", (unsigned long long)lun); 1461 break; 1462 } 1463 } 1464 } 1465 1466 out_err: 1467 kfree(lun_data); 1468 out: 1469 if (scsi_device_created(sdev)) 1470 /* 1471 * the sdev we used didn't appear in the report luns scan 1472 */ 1473 __scsi_remove_device(sdev); 1474 scsi_device_put(sdev); 1475 return ret; 1476 } 1477 1478 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, 1479 uint id, u64 lun, void *hostdata) 1480 { 1481 struct scsi_device *sdev = ERR_PTR(-ENODEV); 1482 struct device *parent = &shost->shost_gendev; 1483 struct scsi_target *starget; 1484 1485 if (strncmp(scsi_scan_type, "none", 4) == 0) 1486 return ERR_PTR(-ENODEV); 1487 1488 starget = scsi_alloc_target(parent, channel, id); 1489 if (!starget) 1490 return ERR_PTR(-ENOMEM); 1491 scsi_autopm_get_target(starget); 1492 1493 mutex_lock(&shost->scan_mutex); 1494 if (!shost->async_scan) 1495 scsi_complete_async_scans(); 1496 1497 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1498 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); 1499 scsi_autopm_put_host(shost); 1500 } 1501 mutex_unlock(&shost->scan_mutex); 1502 scsi_autopm_put_target(starget); 1503 /* 1504 * paired with scsi_alloc_target(). Target will be destroyed unless 1505 * scsi_probe_and_add_lun made an underlying device visible 1506 */ 1507 scsi_target_reap(starget); 1508 put_device(&starget->dev); 1509 1510 return sdev; 1511 } 1512 EXPORT_SYMBOL(__scsi_add_device); 1513 1514 int scsi_add_device(struct Scsi_Host *host, uint channel, 1515 uint target, u64 lun) 1516 { 1517 struct scsi_device *sdev = 1518 __scsi_add_device(host, channel, target, lun, NULL); 1519 if (IS_ERR(sdev)) 1520 return PTR_ERR(sdev); 1521 1522 scsi_device_put(sdev); 1523 return 0; 1524 } 1525 EXPORT_SYMBOL(scsi_add_device); 1526 1527 void scsi_rescan_device(struct device *dev) 1528 { 1529 struct scsi_device *sdev = to_scsi_device(dev); 1530 1531 device_lock(dev); 1532 1533 scsi_attach_vpd(sdev); 1534 1535 if (sdev->handler && sdev->handler->rescan) 1536 sdev->handler->rescan(sdev); 1537 1538 if (dev->driver && try_module_get(dev->driver->owner)) { 1539 struct scsi_driver *drv = to_scsi_driver(dev->driver); 1540 1541 if (drv->rescan) 1542 drv->rescan(dev); 1543 module_put(dev->driver->owner); 1544 } 1545 device_unlock(dev); 1546 } 1547 EXPORT_SYMBOL(scsi_rescan_device); 1548 1549 static void __scsi_scan_target(struct device *parent, unsigned int channel, 1550 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1551 { 1552 struct Scsi_Host *shost = dev_to_shost(parent); 1553 int bflags = 0; 1554 int res; 1555 struct scsi_target *starget; 1556 1557 if (shost->this_id == id) 1558 /* 1559 * Don't scan the host adapter 1560 */ 1561 return; 1562 1563 starget = scsi_alloc_target(parent, channel, id); 1564 if (!starget) 1565 return; 1566 scsi_autopm_get_target(starget); 1567 1568 if (lun != SCAN_WILD_CARD) { 1569 /* 1570 * Scan for a specific host/chan/id/lun. 1571 */ 1572 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); 1573 goto out_reap; 1574 } 1575 1576 /* 1577 * Scan LUN 0, if there is some response, scan further. Ideally, we 1578 * would not configure LUN 0 until all LUNs are scanned. 1579 */ 1580 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); 1581 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { 1582 if (scsi_report_lun_scan(starget, bflags, rescan) != 0) 1583 /* 1584 * The REPORT LUN did not scan the target, 1585 * do a sequential scan. 1586 */ 1587 scsi_sequential_lun_scan(starget, bflags, 1588 starget->scsi_level, rescan); 1589 } 1590 1591 out_reap: 1592 scsi_autopm_put_target(starget); 1593 /* 1594 * paired with scsi_alloc_target(): determine if the target has 1595 * any children at all and if not, nuke it 1596 */ 1597 scsi_target_reap(starget); 1598 1599 put_device(&starget->dev); 1600 } 1601 1602 /** 1603 * scsi_scan_target - scan a target id, possibly including all LUNs on the target. 1604 * @parent: host to scan 1605 * @channel: channel to scan 1606 * @id: target id to scan 1607 * @lun: Specific LUN to scan or SCAN_WILD_CARD 1608 * @rescan: passed to LUN scanning routines; SCSI_SCAN_INITIAL for 1609 * no rescan, SCSI_SCAN_RESCAN to rescan existing LUNs, 1610 * and SCSI_SCAN_MANUAL to force scanning even if 1611 * 'scan=manual' is set. 1612 * 1613 * Description: 1614 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, 1615 * and possibly all LUNs on the target id. 1616 * 1617 * First try a REPORT LUN scan, if that does not scan the target, do a 1618 * sequential scan of LUNs on the target id. 1619 **/ 1620 void scsi_scan_target(struct device *parent, unsigned int channel, 1621 unsigned int id, u64 lun, enum scsi_scan_mode rescan) 1622 { 1623 struct Scsi_Host *shost = dev_to_shost(parent); 1624 1625 if (strncmp(scsi_scan_type, "none", 4) == 0) 1626 return; 1627 1628 if (rescan != SCSI_SCAN_MANUAL && 1629 strncmp(scsi_scan_type, "manual", 6) == 0) 1630 return; 1631 1632 mutex_lock(&shost->scan_mutex); 1633 if (!shost->async_scan) 1634 scsi_complete_async_scans(); 1635 1636 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1637 __scsi_scan_target(parent, channel, id, lun, rescan); 1638 scsi_autopm_put_host(shost); 1639 } 1640 mutex_unlock(&shost->scan_mutex); 1641 } 1642 EXPORT_SYMBOL(scsi_scan_target); 1643 1644 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, 1645 unsigned int id, u64 lun, 1646 enum scsi_scan_mode rescan) 1647 { 1648 uint order_id; 1649 1650 if (id == SCAN_WILD_CARD) 1651 for (id = 0; id < shost->max_id; ++id) { 1652 /* 1653 * XXX adapter drivers when possible (FCP, iSCSI) 1654 * could modify max_id to match the current max, 1655 * not the absolute max. 1656 * 1657 * XXX add a shost id iterator, so for example, 1658 * the FC ID can be the same as a target id 1659 * without a huge overhead of sparse id's. 1660 */ 1661 if (shost->reverse_ordering) 1662 /* 1663 * Scan from high to low id. 1664 */ 1665 order_id = shost->max_id - id - 1; 1666 else 1667 order_id = id; 1668 __scsi_scan_target(&shost->shost_gendev, channel, 1669 order_id, lun, rescan); 1670 } 1671 else 1672 __scsi_scan_target(&shost->shost_gendev, channel, 1673 id, lun, rescan); 1674 } 1675 1676 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, 1677 unsigned int id, u64 lun, 1678 enum scsi_scan_mode rescan) 1679 { 1680 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, 1681 "%s: <%u:%u:%llu>\n", 1682 __func__, channel, id, lun)); 1683 1684 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || 1685 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || 1686 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun))) 1687 return -EINVAL; 1688 1689 mutex_lock(&shost->scan_mutex); 1690 if (!shost->async_scan) 1691 scsi_complete_async_scans(); 1692 1693 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1694 if (channel == SCAN_WILD_CARD) 1695 for (channel = 0; channel <= shost->max_channel; 1696 channel++) 1697 scsi_scan_channel(shost, channel, id, lun, 1698 rescan); 1699 else 1700 scsi_scan_channel(shost, channel, id, lun, rescan); 1701 scsi_autopm_put_host(shost); 1702 } 1703 mutex_unlock(&shost->scan_mutex); 1704 1705 return 0; 1706 } 1707 1708 static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 1709 { 1710 struct scsi_device *sdev; 1711 shost_for_each_device(sdev, shost) { 1712 /* target removed before the device could be added */ 1713 if (sdev->sdev_state == SDEV_DEL) 1714 continue; 1715 /* If device is already visible, skip adding it to sysfs */ 1716 if (sdev->is_visible) 1717 continue; 1718 if (!scsi_host_scan_allowed(shost) || 1719 scsi_sysfs_add_sdev(sdev) != 0) 1720 __scsi_remove_device(sdev); 1721 } 1722 } 1723 1724 /** 1725 * scsi_prep_async_scan - prepare for an async scan 1726 * @shost: the host which will be scanned 1727 * Returns: a cookie to be passed to scsi_finish_async_scan() 1728 * 1729 * Tells the midlayer this host is going to do an asynchronous scan. 1730 * It reserves the host's position in the scanning list and ensures 1731 * that other asynchronous scans started after this one won't affect the 1732 * ordering of the discovered devices. 1733 */ 1734 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 1735 { 1736 struct async_scan_data *data; 1737 unsigned long flags; 1738 1739 if (strncmp(scsi_scan_type, "sync", 4) == 0) 1740 return NULL; 1741 1742 if (shost->async_scan) { 1743 shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__); 1744 return NULL; 1745 } 1746 1747 data = kmalloc(sizeof(*data), GFP_KERNEL); 1748 if (!data) 1749 goto err; 1750 data->shost = scsi_host_get(shost); 1751 if (!data->shost) 1752 goto err; 1753 init_completion(&data->prev_finished); 1754 1755 mutex_lock(&shost->scan_mutex); 1756 spin_lock_irqsave(shost->host_lock, flags); 1757 shost->async_scan = 1; 1758 spin_unlock_irqrestore(shost->host_lock, flags); 1759 mutex_unlock(&shost->scan_mutex); 1760 1761 spin_lock(&async_scan_lock); 1762 if (list_empty(&scanning_hosts)) 1763 complete(&data->prev_finished); 1764 list_add_tail(&data->list, &scanning_hosts); 1765 spin_unlock(&async_scan_lock); 1766 1767 return data; 1768 1769 err: 1770 kfree(data); 1771 return NULL; 1772 } 1773 1774 /** 1775 * scsi_finish_async_scan - asynchronous scan has finished 1776 * @data: cookie returned from earlier call to scsi_prep_async_scan() 1777 * 1778 * All the devices currently attached to this host have been found. 1779 * This function announces all the devices it has found to the rest 1780 * of the system. 1781 */ 1782 static void scsi_finish_async_scan(struct async_scan_data *data) 1783 { 1784 struct Scsi_Host *shost; 1785 unsigned long flags; 1786 1787 if (!data) 1788 return; 1789 1790 shost = data->shost; 1791 1792 mutex_lock(&shost->scan_mutex); 1793 1794 if (!shost->async_scan) { 1795 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); 1796 dump_stack(); 1797 mutex_unlock(&shost->scan_mutex); 1798 return; 1799 } 1800 1801 wait_for_completion(&data->prev_finished); 1802 1803 scsi_sysfs_add_devices(shost); 1804 1805 spin_lock_irqsave(shost->host_lock, flags); 1806 shost->async_scan = 0; 1807 spin_unlock_irqrestore(shost->host_lock, flags); 1808 1809 mutex_unlock(&shost->scan_mutex); 1810 1811 spin_lock(&async_scan_lock); 1812 list_del(&data->list); 1813 if (!list_empty(&scanning_hosts)) { 1814 struct async_scan_data *next = list_entry(scanning_hosts.next, 1815 struct async_scan_data, list); 1816 complete(&next->prev_finished); 1817 } 1818 spin_unlock(&async_scan_lock); 1819 1820 scsi_autopm_put_host(shost); 1821 scsi_host_put(shost); 1822 kfree(data); 1823 } 1824 1825 static void do_scsi_scan_host(struct Scsi_Host *shost) 1826 { 1827 if (shost->hostt->scan_finished) { 1828 unsigned long start = jiffies; 1829 if (shost->hostt->scan_start) 1830 shost->hostt->scan_start(shost); 1831 1832 while (!shost->hostt->scan_finished(shost, jiffies - start)) 1833 msleep(10); 1834 } else { 1835 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, 1836 SCAN_WILD_CARD, 0); 1837 } 1838 } 1839 1840 static void do_scan_async(void *_data, async_cookie_t c) 1841 { 1842 struct async_scan_data *data = _data; 1843 struct Scsi_Host *shost = data->shost; 1844 1845 do_scsi_scan_host(shost); 1846 scsi_finish_async_scan(data); 1847 } 1848 1849 /** 1850 * scsi_scan_host - scan the given adapter 1851 * @shost: adapter to scan 1852 **/ 1853 void scsi_scan_host(struct Scsi_Host *shost) 1854 { 1855 struct async_scan_data *data; 1856 1857 if (strncmp(scsi_scan_type, "none", 4) == 0 || 1858 strncmp(scsi_scan_type, "manual", 6) == 0) 1859 return; 1860 if (scsi_autopm_get_host(shost) < 0) 1861 return; 1862 1863 data = scsi_prep_async_scan(shost); 1864 if (!data) { 1865 do_scsi_scan_host(shost); 1866 scsi_autopm_put_host(shost); 1867 return; 1868 } 1869 1870 /* register with the async subsystem so wait_for_device_probe() 1871 * will flush this work 1872 */ 1873 async_schedule(do_scan_async, data); 1874 1875 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */ 1876 } 1877 EXPORT_SYMBOL(scsi_scan_host); 1878 1879 void scsi_forget_host(struct Scsi_Host *shost) 1880 { 1881 struct scsi_device *sdev; 1882 unsigned long flags; 1883 1884 restart: 1885 spin_lock_irqsave(shost->host_lock, flags); 1886 list_for_each_entry(sdev, &shost->__devices, siblings) { 1887 if (sdev->sdev_state == SDEV_DEL) 1888 continue; 1889 spin_unlock_irqrestore(shost->host_lock, flags); 1890 __scsi_remove_device(sdev); 1891 goto restart; 1892 } 1893 spin_unlock_irqrestore(shost->host_lock, flags); 1894 } 1895 1896 /** 1897 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself 1898 * @shost: Host that needs a scsi_device 1899 * 1900 * Lock status: None assumed. 1901 * 1902 * Returns: The scsi_device or NULL 1903 * 1904 * Notes: 1905 * Attach a single scsi_device to the Scsi_Host - this should 1906 * be made to look like a "pseudo-device" that points to the 1907 * HA itself. 1908 * 1909 * Note - this device is not accessible from any high-level 1910 * drivers (including generics), which is probably not 1911 * optimal. We can add hooks later to attach. 1912 */ 1913 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) 1914 { 1915 struct scsi_device *sdev = NULL; 1916 struct scsi_target *starget; 1917 1918 mutex_lock(&shost->scan_mutex); 1919 if (!scsi_host_scan_allowed(shost)) 1920 goto out; 1921 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); 1922 if (!starget) 1923 goto out; 1924 1925 sdev = scsi_alloc_sdev(starget, 0, NULL); 1926 if (sdev) 1927 sdev->borken = 0; 1928 else 1929 scsi_target_reap(starget); 1930 put_device(&starget->dev); 1931 out: 1932 mutex_unlock(&shost->scan_mutex); 1933 return sdev; 1934 } 1935 EXPORT_SYMBOL(scsi_get_host_dev); 1936 1937 /** 1938 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself 1939 * @sdev: Host device to be freed 1940 * 1941 * Lock status: None assumed. 1942 * 1943 * Returns: Nothing 1944 */ 1945 void scsi_free_host_dev(struct scsi_device *sdev) 1946 { 1947 BUG_ON(sdev->id != sdev->host->this_id); 1948 1949 __scsi_remove_device(sdev); 1950 } 1951 EXPORT_SYMBOL(scsi_free_host_dev); 1952 1953