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 80static const char *scsi_null_device_strs = "nullnullnullnull"; 81 82#define MAX_SCSI_LUNS 512 83 84#ifdef CONFIG_SCSI_MULTI_LUN 85static unsigned int max_scsi_luns = MAX_SCSI_LUNS; 86#else 87static unsigned int max_scsi_luns = 1; 88#endif 89 90module_param_named(max_luns, max_scsi_luns, uint, S_IRUGO|S_IWUSR); 91MODULE_PARM_DESC(max_luns, 92 "last scsi LUN (should be between 1 and 2^32-1)"); 93 94#ifdef CONFIG_SCSI_SCAN_ASYNC 95#define SCSI_SCAN_TYPE_DEFAULT "async" 96#else 97#define SCSI_SCAN_TYPE_DEFAULT "sync" 98#endif 99 100static char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT; 101 102module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO); 103MODULE_PARM_DESC(scan, "sync, async or none"); 104 105/* 106 * max_scsi_report_luns: the maximum number of LUNS that will be 107 * returned from the REPORT LUNS command. 8 times this value must 108 * be allocated. In theory this could be up to an 8 byte value, but 109 * in practice, the maximum number of LUNs suppored by any device 110 * is about 16k. 111 */ 112static unsigned int max_scsi_report_luns = 511; 113 114module_param_named(max_report_luns, max_scsi_report_luns, uint, S_IRUGO|S_IWUSR); 115MODULE_PARM_DESC(max_report_luns, 116 "REPORT LUNS maximum number of LUNS received (should be" 117 " between 1 and 16384)"); 118 119static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18; 120 121module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); 122MODULE_PARM_DESC(inq_timeout, 123 "Timeout (in seconds) waiting for devices to answer INQUIRY." 124 " Default is 20. Some devices may need more; most need less."); 125 126/* This lock protects only this list */ 127static DEFINE_SPINLOCK(async_scan_lock); 128static LIST_HEAD(scanning_hosts); 129 130struct async_scan_data { 131 struct list_head list; 132 struct Scsi_Host *shost; 133 struct completion prev_finished; 134}; 135 136/** 137 * scsi_complete_async_scans - Wait for asynchronous scans to complete 138 * 139 * When this function returns, any host which started scanning before 140 * this function was called will have finished its scan. Hosts which 141 * started scanning after this function was called may or may not have 142 * finished. 143 */ 144int scsi_complete_async_scans(void) 145{ 146 struct async_scan_data *data; 147 148 do { 149 if (list_empty(&scanning_hosts)) 150 return 0; 151 /* If we can't get memory immediately, that's OK. Just 152 * sleep a little. Even if we never get memory, the async 153 * scans will finish eventually. 154 */ 155 data = kmalloc(sizeof(*data), GFP_KERNEL); 156 if (!data) 157 msleep(1); 158 } while (!data); 159 160 data->shost = NULL; 161 init_completion(&data->prev_finished); 162 163 spin_lock(&async_scan_lock); 164 /* Check that there's still somebody else on the list */ 165 if (list_empty(&scanning_hosts)) 166 goto done; 167 list_add_tail(&data->list, &scanning_hosts); 168 spin_unlock(&async_scan_lock); 169 170 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); 171 wait_for_completion(&data->prev_finished); 172 173 spin_lock(&async_scan_lock); 174 list_del(&data->list); 175 if (!list_empty(&scanning_hosts)) { 176 struct async_scan_data *next = list_entry(scanning_hosts.next, 177 struct async_scan_data, list); 178 complete(&next->prev_finished); 179 } 180 done: 181 spin_unlock(&async_scan_lock); 182 183 kfree(data); 184 return 0; 185} 186 187/* Only exported for the benefit of scsi_wait_scan */ 188EXPORT_SYMBOL_GPL(scsi_complete_async_scans); 189 190#ifndef MODULE 191/* 192 * For async scanning we need to wait for all the scans to complete before 193 * trying to mount the root fs. Otherwise non-modular drivers may not be ready 194 * yet. 195 */ 196late_initcall(scsi_complete_async_scans); 197#endif 198 199/** 200 * scsi_unlock_floptical - unlock device via a special MODE SENSE command 201 * @sdev: scsi device to send command to 202 * @result: area to store the result of the MODE SENSE 203 * 204 * Description: 205 * Send a vendor specific MODE SENSE (not a MODE SELECT) command. 206 * Called for BLIST_KEY devices. 207 **/ 208static void scsi_unlock_floptical(struct scsi_device *sdev, 209 unsigned char *result) 210{ 211 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 212 213 printk(KERN_NOTICE "scsi: unlocking floptical drive\n"); 214 scsi_cmd[0] = MODE_SENSE; 215 scsi_cmd[1] = 0; 216 scsi_cmd[2] = 0x2e; 217 scsi_cmd[3] = 0; 218 scsi_cmd[4] = 0x2a; /* size */ 219 scsi_cmd[5] = 0; 220 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, 221 SCSI_TIMEOUT, 3, NULL); 222} 223 224/** 225 * scsi_alloc_sdev - allocate and setup a scsi_Device 226 * @starget: which target to allocate a &scsi_device for 227 * @lun: which lun 228 * @hostdata: usually NULL and set by ->slave_alloc instead 229 * 230 * Description: 231 * Allocate, initialize for io, and return a pointer to a scsi_Device. 232 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and 233 * adds scsi_Device to the appropriate list. 234 * 235 * Return value: 236 * scsi_Device pointer, or NULL on failure. 237 **/ 238static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, 239 unsigned int lun, void *hostdata) 240{ 241 struct scsi_device *sdev; 242 int display_failure_msg = 1, ret; 243 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 244 extern void scsi_evt_thread(struct work_struct *work); 245 246 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, 247 GFP_ATOMIC); 248 if (!sdev) 249 goto out; 250 251 sdev->vendor = scsi_null_device_strs; 252 sdev->model = scsi_null_device_strs; 253 sdev->rev = scsi_null_device_strs; 254 sdev->host = shost; 255 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD; 256 sdev->id = starget->id; 257 sdev->lun = lun; 258 sdev->channel = starget->channel; 259 sdev->sdev_state = SDEV_CREATED; 260 INIT_LIST_HEAD(&sdev->siblings); 261 INIT_LIST_HEAD(&sdev->same_target_siblings); 262 INIT_LIST_HEAD(&sdev->cmd_list); 263 INIT_LIST_HEAD(&sdev->starved_entry); 264 INIT_LIST_HEAD(&sdev->event_list); 265 spin_lock_init(&sdev->list_lock); 266 INIT_WORK(&sdev->event_work, scsi_evt_thread); 267 268 sdev->sdev_gendev.parent = get_device(&starget->dev); 269 sdev->sdev_target = starget; 270 271 /* usually NULL and set by ->slave_alloc instead */ 272 sdev->hostdata = hostdata; 273 274 /* if the device needs this changing, it may do so in the 275 * slave_configure function */ 276 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; 277 278 /* 279 * Some low level driver could use device->type 280 */ 281 sdev->type = -1; 282 283 /* 284 * Assume that the device will have handshaking problems, 285 * and then fix this field later if it turns out it 286 * doesn't 287 */ 288 sdev->borken = 1; 289 290 sdev->request_queue = scsi_alloc_queue(sdev); 291 if (!sdev->request_queue) { 292 /* release fn is set up in scsi_sysfs_device_initialise, so 293 * have to free and put manually here */ 294 put_device(&starget->dev); 295 kfree(sdev); 296 goto out; 297 } 298 299 sdev->request_queue->queuedata = sdev; 300 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); 301 302 scsi_sysfs_device_initialize(sdev); 303 304 if (shost->hostt->slave_alloc) { 305 ret = shost->hostt->slave_alloc(sdev); 306 if (ret) { 307 /* 308 * if LLDD reports slave not present, don't clutter 309 * console with alloc failure messages 310 */ 311 if (ret == -ENXIO) 312 display_failure_msg = 0; 313 goto out_device_destroy; 314 } 315 } 316 317 return sdev; 318 319out_device_destroy: 320 scsi_device_set_state(sdev, SDEV_DEL); 321 transport_destroy_device(&sdev->sdev_gendev); 322 put_device(&sdev->sdev_dev); 323 put_device(&sdev->sdev_gendev); 324out: 325 if (display_failure_msg) 326 printk(ALLOC_FAILURE_MSG, __func__); 327 return NULL; 328} 329 330static void scsi_target_destroy(struct scsi_target *starget) 331{ 332 struct device *dev = &starget->dev; 333 struct Scsi_Host *shost = dev_to_shost(dev->parent); 334 unsigned long flags; 335 336 transport_destroy_device(dev); 337 spin_lock_irqsave(shost->host_lock, flags); 338 if (shost->hostt->target_destroy) 339 shost->hostt->target_destroy(starget); 340 list_del_init(&starget->siblings); 341 spin_unlock_irqrestore(shost->host_lock, flags); 342 put_device(dev); 343} 344 345static void scsi_target_dev_release(struct device *dev) 346{ 347 struct device *parent = dev->parent; 348 struct scsi_target *starget = to_scsi_target(dev); 349 350 kfree(starget); 351 put_device(parent); 352} 353 354static struct device_type scsi_target_type = { 355 .name = "scsi_target", 356 .release = scsi_target_dev_release, 357}; 358 359int scsi_is_target_device(const struct device *dev) 360{ 361 return dev->type == &scsi_target_type; 362} 363EXPORT_SYMBOL(scsi_is_target_device); 364 365static struct scsi_target *__scsi_find_target(struct device *parent, 366 int channel, uint id) 367{ 368 struct scsi_target *starget, *found_starget = NULL; 369 struct Scsi_Host *shost = dev_to_shost(parent); 370 /* 371 * Search for an existing target for this sdev. 372 */ 373 list_for_each_entry(starget, &shost->__targets, siblings) { 374 if (starget->id == id && 375 starget->channel == channel) { 376 found_starget = starget; 377 break; 378 } 379 } 380 if (found_starget) 381 get_device(&found_starget->dev); 382 383 return found_starget; 384} 385 386/** 387 * scsi_alloc_target - allocate a new or find an existing target 388 * @parent: parent of the target (need not be a scsi host) 389 * @channel: target channel number (zero if no channels) 390 * @id: target id number 391 * 392 * Return an existing target if one exists, provided it hasn't already 393 * gone into STARGET_DEL state, otherwise allocate a new target. 394 * 395 * The target is returned with an incremented reference, so the caller 396 * is responsible for both reaping and doing a last put 397 */ 398static struct scsi_target *scsi_alloc_target(struct device *parent, 399 int channel, uint id) 400{ 401 struct Scsi_Host *shost = dev_to_shost(parent); 402 struct device *dev = NULL; 403 unsigned long flags; 404 const int size = sizeof(struct scsi_target) 405 + shost->transportt->target_size; 406 struct scsi_target *starget; 407 struct scsi_target *found_target; 408 int error; 409 410 starget = kzalloc(size, GFP_KERNEL); 411 if (!starget) { 412 printk(KERN_ERR "%s: allocation failure\n", __func__); 413 return NULL; 414 } 415 dev = &starget->dev; 416 device_initialize(dev); 417 starget->reap_ref = 1; 418 dev->parent = get_device(parent); 419 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); 420#ifndef CONFIG_SYSFS_DEPRECATED 421 dev->bus = &scsi_bus_type; 422#endif 423 dev->type = &scsi_target_type; 424 starget->id = id; 425 starget->channel = channel; 426 starget->can_queue = 0; 427 INIT_LIST_HEAD(&starget->siblings); 428 INIT_LIST_HEAD(&starget->devices); 429 starget->state = STARGET_CREATED; 430 starget->scsi_level = SCSI_2; 431 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; 432 retry: 433 spin_lock_irqsave(shost->host_lock, flags); 434 435 found_target = __scsi_find_target(parent, channel, id); 436 if (found_target) 437 goto found; 438 439 list_add_tail(&starget->siblings, &shost->__targets); 440 spin_unlock_irqrestore(shost->host_lock, flags); 441 /* allocate and add */ 442 transport_setup_device(dev); 443 if (shost->hostt->target_alloc) { 444 error = shost->hostt->target_alloc(starget); 445 446 if(error) { 447 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error); 448 /* don't want scsi_target_reap to do the final 449 * put because it will be under the host lock */ 450 scsi_target_destroy(starget); 451 return NULL; 452 } 453 } 454 get_device(dev); 455 456 return starget; 457 458 found: 459 found_target->reap_ref++; 460 spin_unlock_irqrestore(shost->host_lock, flags); 461 if (found_target->state != STARGET_DEL) { 462 put_device(dev); 463 return found_target; 464 } 465 /* Unfortunately, we found a dying target; need to 466 * wait until it's dead before we can get a new one */ 467 put_device(&found_target->dev); 468 flush_scheduled_work(); 469 goto retry; 470} 471 472static void scsi_target_reap_usercontext(struct work_struct *work) 473{ 474 struct scsi_target *starget = 475 container_of(work, struct scsi_target, ew.work); 476 477 transport_remove_device(&starget->dev); 478 device_del(&starget->dev); 479 scsi_target_destroy(starget); 480} 481 482/** 483 * scsi_target_reap - check to see if target is in use and destroy if not 484 * @starget: target to be checked 485 * 486 * This is used after removing a LUN or doing a last put of the target 487 * it checks atomically that nothing is using the target and removes 488 * it if so. 489 */ 490void scsi_target_reap(struct scsi_target *starget) 491{ 492 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 493 unsigned long flags; 494 enum scsi_target_state state; 495 int empty = 0; 496 497 spin_lock_irqsave(shost->host_lock, flags); 498 state = starget->state; 499 if (--starget->reap_ref == 0 && list_empty(&starget->devices)) { 500 empty = 1; 501 starget->state = STARGET_DEL; 502 } 503 spin_unlock_irqrestore(shost->host_lock, flags); 504 505 if (!empty) 506 return; 507 508 BUG_ON(state == STARGET_DEL); 509 if (state == STARGET_CREATED) 510 scsi_target_destroy(starget); 511 else 512 execute_in_process_context(scsi_target_reap_usercontext, 513 &starget->ew); 514} 515 516/** 517 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string 518 * @s: INQUIRY result string to sanitize 519 * @len: length of the string 520 * 521 * Description: 522 * The SCSI spec says that INQUIRY vendor, product, and revision 523 * strings must consist entirely of graphic ASCII characters, 524 * padded on the right with spaces. Since not all devices obey 525 * this rule, we will replace non-graphic or non-ASCII characters 526 * with spaces. Exception: a NUL character is interpreted as a 527 * string terminator, so all the following characters are set to 528 * spaces. 529 **/ 530static void sanitize_inquiry_string(unsigned char *s, int len) 531{ 532 int terminated = 0; 533 534 for (; len > 0; (--len, ++s)) { 535 if (*s == 0) 536 terminated = 1; 537 if (terminated || *s < 0x20 || *s > 0x7e) 538 *s = ' '; 539 } 540} 541 542/** 543 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY 544 * @sdev: scsi_device to probe 545 * @inq_result: area to store the INQUIRY result 546 * @result_len: len of inq_result 547 * @bflags: store any bflags found here 548 * 549 * Description: 550 * Probe the lun associated with @req using a standard SCSI INQUIRY; 551 * 552 * If the INQUIRY is successful, zero is returned and the 553 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length 554 * are copied to the scsi_device any flags value is stored in *@bflags. 555 **/ 556static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, 557 int result_len, int *bflags) 558{ 559 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 560 int first_inquiry_len, try_inquiry_len, next_inquiry_len; 561 int response_len = 0; 562 int pass, count, result; 563 struct scsi_sense_hdr sshdr; 564 565 *bflags = 0; 566 567 /* Perform up to 3 passes. The first pass uses a conservative 568 * transfer length of 36 unless sdev->inquiry_len specifies a 569 * different value. */ 570 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; 571 try_inquiry_len = first_inquiry_len; 572 pass = 1; 573 574 next_pass: 575 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, 576 "scsi scan: INQUIRY pass %d length %d\n", 577 pass, try_inquiry_len)); 578 579 /* Each pass gets up to three chances to ignore Unit Attention */ 580 for (count = 0; count < 3; ++count) { 581 int resid; 582 583 memset(scsi_cmd, 0, 6); 584 scsi_cmd[0] = INQUIRY; 585 scsi_cmd[4] = (unsigned char) try_inquiry_len; 586 587 memset(inq_result, 0, try_inquiry_len); 588 589 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 590 inq_result, try_inquiry_len, &sshdr, 591 HZ / 2 + HZ * scsi_inq_timeout, 3, 592 &resid); 593 594 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s " 595 "with code 0x%x\n", 596 result ? "failed" : "successful", result)); 597 598 if (result) { 599 /* 600 * not-ready to ready transition [asc/ascq=0x28/0x0] 601 * or power-on, reset [asc/ascq=0x29/0x0], continue. 602 * INQUIRY should not yield UNIT_ATTENTION 603 * but many buggy devices do so anyway. 604 */ 605 if ((driver_byte(result) & DRIVER_SENSE) && 606 scsi_sense_valid(&sshdr)) { 607 if ((sshdr.sense_key == UNIT_ATTENTION) && 608 ((sshdr.asc == 0x28) || 609 (sshdr.asc == 0x29)) && 610 (sshdr.ascq == 0)) 611 continue; 612 } 613 } else { 614 if (resid == try_inquiry_len) 615 continue; 616 } 617 break; 618 } 619 620 if (result == 0) { 621 sanitize_inquiry_string(&inq_result[8], 8); 622 sanitize_inquiry_string(&inq_result[16], 16); 623 sanitize_inquiry_string(&inq_result[32], 4); 624 625 response_len = inq_result[4] + 5; 626 if (response_len > 255) 627 response_len = first_inquiry_len; /* sanity */ 628 629 *bflags = scsi_get_device_flags(sdev, &inq_result[8], 630 &inq_result[16]); 631 632 /* When the first pass succeeds we gain information about 633 * what larger transfer lengths might work. */ 634 if (pass == 1) { 635 if (BLIST_INQUIRY_36 & *bflags) 636 next_inquiry_len = 36; 637 else if (BLIST_INQUIRY_58 & *bflags) 638 next_inquiry_len = 58; 639 else if (sdev->inquiry_len) 640 next_inquiry_len = sdev->inquiry_len; 641 else 642 next_inquiry_len = response_len; 643 644 /* If more data is available perform the second pass */ 645 if (next_inquiry_len > try_inquiry_len) { 646 try_inquiry_len = next_inquiry_len; 647 pass = 2; 648 goto next_pass; 649 } 650 } 651 652 } else if (pass == 2) { 653 printk(KERN_INFO "scsi scan: %d byte inquiry failed. " 654 "Consider BLIST_INQUIRY_36 for this device\n", 655 try_inquiry_len); 656 657 /* If this pass failed, the third pass goes back and transfers 658 * the same amount as we successfully got in the first pass. */ 659 try_inquiry_len = first_inquiry_len; 660 pass = 3; 661 goto next_pass; 662 } 663 664 /* If the last transfer attempt got an error, assume the 665 * peripheral doesn't exist or is dead. */ 666 if (result) 667 return -EIO; 668 669 /* Don't report any more data than the device says is valid */ 670 sdev->inquiry_len = min(try_inquiry_len, response_len); 671 672 if (sdev->inquiry_len < 36) { 673 printk(KERN_INFO "scsi scan: INQUIRY result too short (%d)," 674 " using 36\n", sdev->inquiry_len); 675 sdev->inquiry_len = 36; 676 } 677 678 679 /* 680 * The scanning code needs to know the scsi_level, even if no 681 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so 682 * non-zero LUNs can be scanned. 683 */ 684 sdev->scsi_level = inq_result[2] & 0x07; 685 if (sdev->scsi_level >= 2 || 686 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) 687 sdev->scsi_level++; 688 sdev->sdev_target->scsi_level = sdev->scsi_level; 689 690 return 0; 691} 692 693/** 694 * scsi_add_lun - allocate and fully initialze a scsi_device 695 * @sdev: holds information to be stored in the new scsi_device 696 * @inq_result: holds the result of a previous INQUIRY to the LUN 697 * @bflags: black/white list flag 698 * @async: 1 if this device is being scanned asynchronously 699 * 700 * Description: 701 * Initialize the scsi_device @sdev. Optionally set fields based 702 * on values in *@bflags. 703 * 704 * Return: 705 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 706 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 707 **/ 708static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, 709 int *bflags, int async) 710{ 711 int ret; 712 713 714 /* 715 * Copy at least 36 bytes of INQUIRY data, so that we don't 716 * dereference unallocated memory when accessing the Vendor, 717 * Product, and Revision strings. Badly behaved devices may set 718 * the INQUIRY Additional Length byte to a small value, indicating 719 * these strings are invalid, but often they contain plausible data 720 * nonetheless. It doesn't matter if the device sent < 36 bytes 721 * total, since scsi_probe_lun() initializes inq_result with 0s. 722 */ 723 sdev->inquiry = kmemdup(inq_result, 724 max_t(size_t, sdev->inquiry_len, 36), 725 GFP_ATOMIC); 726 if (sdev->inquiry == NULL) 727 return SCSI_SCAN_NO_RESPONSE; 728 729 sdev->vendor = (char *) (sdev->inquiry + 8); 730 sdev->model = (char *) (sdev->inquiry + 16); 731 sdev->rev = (char *) (sdev->inquiry + 32); 732 733 if (*bflags & BLIST_ISROM) { 734 sdev->type = TYPE_ROM; 735 sdev->removable = 1; 736 } else { 737 sdev->type = (inq_result[0] & 0x1f); 738 sdev->removable = (inq_result[1] & 0x80) >> 7; 739 } 740 741 switch (sdev->type) { 742 case TYPE_RBC: 743 case TYPE_TAPE: 744 case TYPE_DISK: 745 case TYPE_PRINTER: 746 case TYPE_MOD: 747 case TYPE_PROCESSOR: 748 case TYPE_SCANNER: 749 case TYPE_MEDIUM_CHANGER: 750 case TYPE_ENCLOSURE: 751 case TYPE_COMM: 752 case TYPE_RAID: 753 case TYPE_OSD: 754 sdev->writeable = 1; 755 break; 756 case TYPE_ROM: 757 case TYPE_WORM: 758 sdev->writeable = 0; 759 break; 760 default: 761 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type); 762 } 763 764 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { 765 /* RBC and MMC devices can return SCSI-3 compliance and yet 766 * still not support REPORT LUNS, so make them act as 767 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is 768 * specifically set */ 769 if ((*bflags & BLIST_REPORTLUN2) == 0) 770 *bflags |= BLIST_NOREPORTLUN; 771 } 772 773 /* 774 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI 775 * spec says: The device server is capable of supporting the 776 * specified peripheral device type on this logical unit. However, 777 * the physical device is not currently connected to this logical 778 * unit. 779 * 780 * The above is vague, as it implies that we could treat 001 and 781 * 011 the same. Stay compatible with previous code, and create a 782 * scsi_device for a PQ of 1 783 * 784 * Don't set the device offline here; rather let the upper 785 * level drivers eval the PQ to decide whether they should 786 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. 787 */ 788 789 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; 790 sdev->lockable = sdev->removable; 791 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); 792 793 if (sdev->scsi_level >= SCSI_3 || 794 (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) 795 sdev->ppr = 1; 796 if (inq_result[7] & 0x60) 797 sdev->wdtr = 1; 798 if (inq_result[7] & 0x10) 799 sdev->sdtr = 1; 800 801 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " 802 "ANSI: %d%s\n", scsi_device_type(sdev->type), 803 sdev->vendor, sdev->model, sdev->rev, 804 sdev->inq_periph_qual, inq_result[2] & 0x07, 805 (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); 806 807 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && 808 !(*bflags & BLIST_NOTQ)) 809 sdev->tagged_supported = 1; 810 811 /* 812 * Some devices (Texel CD ROM drives) have handshaking problems 813 * when used with the Seagate controllers. borken is initialized 814 * to 1, and then set it to 0 here. 815 */ 816 if ((*bflags & BLIST_BORKEN) == 0) 817 sdev->borken = 0; 818 819 if (*bflags & BLIST_NO_ULD_ATTACH) 820 sdev->no_uld_attach = 1; 821 822 /* 823 * Apparently some really broken devices (contrary to the SCSI 824 * standards) need to be selected without asserting ATN 825 */ 826 if (*bflags & BLIST_SELECT_NO_ATN) 827 sdev->select_no_atn = 1; 828 829 /* 830 * Maximum 512 sector transfer length 831 * broken RA4x00 Compaq Disk Array 832 */ 833 if (*bflags & BLIST_MAX_512) 834 blk_queue_max_hw_sectors(sdev->request_queue, 512); 835 836 /* 837 * Some devices may not want to have a start command automatically 838 * issued when a device is added. 839 */ 840 if (*bflags & BLIST_NOSTARTONADD) 841 sdev->no_start_on_add = 1; 842 843 if (*bflags & BLIST_SINGLELUN) 844 scsi_target(sdev)->single_lun = 1; 845 846 sdev->use_10_for_rw = 1; 847 848 if (*bflags & BLIST_MS_SKIP_PAGE_08) 849 sdev->skip_ms_page_8 = 1; 850 851 if (*bflags & BLIST_MS_SKIP_PAGE_3F) 852 sdev->skip_ms_page_3f = 1; 853 854 if (*bflags & BLIST_USE_10_BYTE_MS) 855 sdev->use_10_for_ms = 1; 856 857 /* set the device running here so that slave configure 858 * may do I/O */ 859 ret = scsi_device_set_state(sdev, SDEV_RUNNING); 860 if (ret) { 861 ret = scsi_device_set_state(sdev, SDEV_BLOCK); 862 863 if (ret) { 864 sdev_printk(KERN_ERR, sdev, 865 "in wrong state %s to complete scan\n", 866 scsi_device_state_name(sdev->sdev_state)); 867 return SCSI_SCAN_NO_RESPONSE; 868 } 869 } 870 871 if (*bflags & BLIST_MS_192_BYTES_FOR_3F) 872 sdev->use_192_bytes_for_3f = 1; 873 874 if (*bflags & BLIST_NOT_LOCKABLE) 875 sdev->lockable = 0; 876 877 if (*bflags & BLIST_RETRY_HWERROR) 878 sdev->retry_hwerror = 1; 879 880 transport_configure_device(&sdev->sdev_gendev); 881 882 if (sdev->host->hostt->slave_configure) { 883 ret = sdev->host->hostt->slave_configure(sdev); 884 if (ret) { 885 /* 886 * if LLDD reports slave not present, don't clutter 887 * console with alloc failure messages 888 */ 889 if (ret != -ENXIO) { 890 sdev_printk(KERN_ERR, sdev, 891 "failed to configure device\n"); 892 } 893 return SCSI_SCAN_NO_RESPONSE; 894 } 895 } 896 897 sdev->max_queue_depth = sdev->queue_depth; 898 899 /* 900 * Ok, the device is now all set up, we can 901 * register it and tell the rest of the kernel 902 * about it. 903 */ 904 if (!async && scsi_sysfs_add_sdev(sdev) != 0) 905 return SCSI_SCAN_NO_RESPONSE; 906 907 return SCSI_SCAN_LUN_PRESENT; 908} 909 910#ifdef CONFIG_SCSI_LOGGING 911/** 912 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace 913 * @buf: Output buffer with at least end-first+1 bytes of space 914 * @inq: Inquiry buffer (input) 915 * @first: Offset of string into inq 916 * @end: Index after last character in inq 917 */ 918static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, 919 unsigned first, unsigned end) 920{ 921 unsigned term = 0, idx; 922 923 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { 924 if (inq[idx+first] > ' ') { 925 buf[idx] = inq[idx+first]; 926 term = idx+1; 927 } else { 928 buf[idx] = ' '; 929 } 930 } 931 buf[term] = 0; 932 return buf; 933} 934#endif 935 936/** 937 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it 938 * @starget: pointer to target device structure 939 * @lun: LUN of target device 940 * @bflagsp: store bflags here if not NULL 941 * @sdevp: probe the LUN corresponding to this scsi_device 942 * @rescan: if nonzero skip some code only needed on first scan 943 * @hostdata: passed to scsi_alloc_sdev() 944 * 945 * Description: 946 * Call scsi_probe_lun, if a LUN with an attached device is found, 947 * allocate and set it up by calling scsi_add_lun. 948 * 949 * Return: 950 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device 951 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is 952 * attached at the LUN 953 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized 954 **/ 955static int scsi_probe_and_add_lun(struct scsi_target *starget, 956 uint lun, int *bflagsp, 957 struct scsi_device **sdevp, int rescan, 958 void *hostdata) 959{ 960 struct scsi_device *sdev; 961 unsigned char *result; 962 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256; 963 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 964 965 /* 966 * The rescan flag is used as an optimization, the first scan of a 967 * host adapter calls into here with rescan == 0. 968 */ 969 sdev = scsi_device_lookup_by_target(starget, lun); 970 if (sdev) { 971 if (rescan || !scsi_device_created(sdev)) { 972 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO 973 "scsi scan: device exists on %s\n", 974 dev_name(&sdev->sdev_gendev))); 975 if (sdevp) 976 *sdevp = sdev; 977 else 978 scsi_device_put(sdev); 979 980 if (bflagsp) 981 *bflagsp = scsi_get_device_flags(sdev, 982 sdev->vendor, 983 sdev->model); 984 return SCSI_SCAN_LUN_PRESENT; 985 } 986 scsi_device_put(sdev); 987 } else 988 sdev = scsi_alloc_sdev(starget, lun, hostdata); 989 if (!sdev) 990 goto out; 991 992 result = kmalloc(result_len, GFP_ATOMIC | 993 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0)); 994 if (!result) 995 goto out_free_sdev; 996 997 if (scsi_probe_lun(sdev, result, result_len, &bflags)) 998 goto out_free_result; 999 1000 if (bflagsp) 1001 *bflagsp = bflags; 1002 /* 1003 * result contains valid SCSI INQUIRY data. 1004 */ 1005 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) { 1006 /* 1007 * For a Peripheral qualifier 3 (011b), the SCSI 1008 * spec says: The device server is not capable of 1009 * supporting a physical device on this logical 1010 * unit. 1011 * 1012 * For disks, this implies that there is no 1013 * logical disk configured at sdev->lun, but there 1014 * is a target id responding. 1015 */ 1016 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" 1017 " peripheral qualifier of 3, device not" 1018 " added\n")) 1019 if (lun == 0) { 1020 SCSI_LOG_SCAN_BUS(1, { 1021 unsigned char vend[9]; 1022 unsigned char mod[17]; 1023 1024 sdev_printk(KERN_INFO, sdev, 1025 "scsi scan: consider passing scsi_mod." 1026 "dev_flags=%s:%s:0x240 or 0x1000240\n", 1027 scsi_inq_str(vend, result, 8, 16), 1028 scsi_inq_str(mod, result, 16, 32)); 1029 }); 1030 1031 } 1032 1033 res = SCSI_SCAN_TARGET_PRESENT; 1034 goto out_free_result; 1035 } 1036 1037 /* 1038 * Some targets may set slight variations of PQ and PDT to signal 1039 * that no LUN is present, so don't add sdev in these cases. 1040 * Two specific examples are: 1041 * 1) NetApp targets: return PQ=1, PDT=0x1f 1042 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" 1043 * in the UFI 1.0 spec (we cannot rely on reserved bits). 1044 * 1045 * References: 1046 * 1) SCSI SPC-3, pp. 145-146 1047 * PQ=1: "A peripheral device having the specified peripheral 1048 * device type is not connected to this logical unit. However, the 1049 * device server is capable of supporting the specified peripheral 1050 * device type on this logical unit." 1051 * PDT=0x1f: "Unknown or no device type" 1052 * 2) USB UFI 1.0, p. 20 1053 * PDT=00h Direct-access device (floppy) 1054 * PDT=1Fh none (no FDD connected to the requested logical unit) 1055 */ 1056 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) && 1057 (result[0] & 0x1f) == 0x1f && 1058 !scsi_is_wlun(lun)) { 1059 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO 1060 "scsi scan: peripheral device type" 1061 " of 31, no device added\n")); 1062 res = SCSI_SCAN_TARGET_PRESENT; 1063 goto out_free_result; 1064 } 1065 1066 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); 1067 if (res == SCSI_SCAN_LUN_PRESENT) { 1068 if (bflags & BLIST_KEY) { 1069 sdev->lockable = 0; 1070 scsi_unlock_floptical(sdev, result); 1071 } 1072 } 1073 1074 out_free_result: 1075 kfree(result); 1076 out_free_sdev: 1077 if (res == SCSI_SCAN_LUN_PRESENT) { 1078 if (sdevp) { 1079 if (scsi_device_get(sdev) == 0) { 1080 *sdevp = sdev; 1081 } else { 1082 __scsi_remove_device(sdev); 1083 res = SCSI_SCAN_NO_RESPONSE; 1084 } 1085 } 1086 } else 1087 __scsi_remove_device(sdev); 1088 out: 1089 return res; 1090} 1091 1092/** 1093 * scsi_sequential_lun_scan - sequentially scan a SCSI target 1094 * @starget: pointer to target structure to scan 1095 * @bflags: black/white list flag for LUN 0 1096 * @scsi_level: Which version of the standard does this device adhere to 1097 * @rescan: passed to scsi_probe_add_lun() 1098 * 1099 * Description: 1100 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been 1101 * scanned) to some maximum lun until a LUN is found with no device 1102 * attached. Use the bflags to figure out any oddities. 1103 * 1104 * Modifies sdevscan->lun. 1105 **/ 1106static void scsi_sequential_lun_scan(struct scsi_target *starget, 1107 int bflags, int scsi_level, int rescan) 1108{ 1109 unsigned int sparse_lun, lun, max_dev_lun; 1110 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1111 1112 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of" 1113 "%s\n", dev_name(&starget->dev))); 1114 1115 max_dev_lun = min(max_scsi_luns, shost->max_lun); 1116 /* 1117 * If this device is known to support sparse multiple units, 1118 * override the other settings, and scan all of them. Normally, 1119 * SCSI-3 devices should be scanned via the REPORT LUNS. 1120 */ 1121 if (bflags & BLIST_SPARSELUN) { 1122 max_dev_lun = shost->max_lun; 1123 sparse_lun = 1; 1124 } else 1125 sparse_lun = 0; 1126 1127 /* 1128 * If less than SCSI_1_CSS, and no special lun scaning, stop 1129 * scanning; this matches 2.4 behaviour, but could just be a bug 1130 * (to continue scanning a SCSI_1_CSS device). 1131 * 1132 * This test is broken. We might not have any device on lun0 for 1133 * a sparselun device, and if that's the case then how would we 1134 * know the real scsi_level, eh? It might make sense to just not 1135 * scan any SCSI_1 device for non-0 luns, but that check would best 1136 * go into scsi_alloc_sdev() and just have it return null when asked 1137 * to alloc an sdev for lun > 0 on an already found SCSI_1 device. 1138 * 1139 if ((sdevscan->scsi_level < SCSI_1_CCS) && 1140 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) 1141 == 0)) 1142 return; 1143 */ 1144 /* 1145 * If this device is known to support multiple units, override 1146 * the other settings, and scan all of them. 1147 */ 1148 if (bflags & BLIST_FORCELUN) 1149 max_dev_lun = shost->max_lun; 1150 /* 1151 * REGAL CDC-4X: avoid hang after LUN 4 1152 */ 1153 if (bflags & BLIST_MAX5LUN) 1154 max_dev_lun = min(5U, max_dev_lun); 1155 /* 1156 * Do not scan SCSI-2 or lower device past LUN 7, unless 1157 * BLIST_LARGELUN. 1158 */ 1159 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) 1160 max_dev_lun = min(8U, max_dev_lun); 1161 1162 /* 1163 * We have already scanned LUN 0, so start at LUN 1. Keep scanning 1164 * until we reach the max, or no LUN is found and we are not 1165 * sparse_lun. 1166 */ 1167 for (lun = 1; lun < max_dev_lun; ++lun) 1168 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, 1169 NULL) != SCSI_SCAN_LUN_PRESENT) && 1170 !sparse_lun) 1171 return; 1172} 1173 1174/** 1175 * scsilun_to_int - convert a scsi_lun to an int 1176 * @scsilun: struct scsi_lun to be converted. 1177 * 1178 * Description: 1179 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered 1180 * integer, and return the result. The caller must check for 1181 * truncation before using this function. 1182 * 1183 * Notes: 1184 * The struct scsi_lun is assumed to be four levels, with each level 1185 * effectively containing a SCSI byte-ordered (big endian) short; the 1186 * addressing bits of each level are ignored (the highest two bits). 1187 * For a description of the LUN format, post SCSI-3 see the SCSI 1188 * Architecture Model, for SCSI-3 see the SCSI Controller Commands. 1189 * 1190 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns 1191 * the integer: 0x0b030a04 1192 **/ 1193int scsilun_to_int(struct scsi_lun *scsilun) 1194{ 1195 int i; 1196 unsigned int lun; 1197 1198 lun = 0; 1199 for (i = 0; i < sizeof(lun); i += 2) 1200 lun = lun | (((scsilun->scsi_lun[i] << 8) | 1201 scsilun->scsi_lun[i + 1]) << (i * 8)); 1202 return lun; 1203} 1204EXPORT_SYMBOL(scsilun_to_int); 1205 1206/** 1207 * int_to_scsilun - reverts an int into a scsi_lun 1208 * @lun: integer to be reverted 1209 * @scsilun: struct scsi_lun to be set. 1210 * 1211 * Description: 1212 * Reverts the functionality of the scsilun_to_int, which packed 1213 * an 8-byte lun value into an int. This routine unpacks the int 1214 * back into the lun value. 1215 * Note: the scsilun_to_int() routine does not truly handle all 1216 * 8bytes of the lun value. This functions restores only as much 1217 * as was set by the routine. 1218 * 1219 * Notes: 1220 * Given an integer : 0x0b030a04, this function returns a 1221 * scsi_lun of : struct scsi_lun of: 0a 04 0b 03 00 00 00 00 1222 * 1223 **/ 1224void int_to_scsilun(unsigned int lun, struct scsi_lun *scsilun) 1225{ 1226 int i; 1227 1228 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun)); 1229 1230 for (i = 0; i < sizeof(lun); i += 2) { 1231 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF; 1232 scsilun->scsi_lun[i+1] = lun & 0xFF; 1233 lun = lun >> 16; 1234 } 1235} 1236EXPORT_SYMBOL(int_to_scsilun); 1237 1238/** 1239 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results 1240 * @starget: which target 1241 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN 1242 * @rescan: nonzero if we can skip code only needed on first scan 1243 * 1244 * Description: 1245 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. 1246 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. 1247 * 1248 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 1249 * LUNs even if it's older than SCSI-3. 1250 * If BLIST_NOREPORTLUN is set, return 1 always. 1251 * If BLIST_NOLUN is set, return 0 always. 1252 * 1253 * Return: 1254 * 0: scan completed (or no memory, so further scanning is futile) 1255 * 1: could not scan with REPORT LUN 1256 **/ 1257static int scsi_report_lun_scan(struct scsi_target *starget, int bflags, 1258 int rescan) 1259{ 1260 char devname[64]; 1261 unsigned char scsi_cmd[MAX_COMMAND_SIZE]; 1262 unsigned int length; 1263 unsigned int lun; 1264 unsigned int num_luns; 1265 unsigned int retries; 1266 int result; 1267 struct scsi_lun *lunp, *lun_data; 1268 u8 *data; 1269 struct scsi_sense_hdr sshdr; 1270 struct scsi_device *sdev; 1271 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 1272 int ret = 0; 1273 1274 /* 1275 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. 1276 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does 1277 * support more than 8 LUNs. 1278 */ 1279 if (bflags & BLIST_NOREPORTLUN) 1280 return 1; 1281 if (starget->scsi_level < SCSI_2 && 1282 starget->scsi_level != SCSI_UNKNOWN) 1283 return 1; 1284 if (starget->scsi_level < SCSI_3 && 1285 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) 1286 return 1; 1287 if (bflags & BLIST_NOLUN) 1288 return 0; 1289 1290 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { 1291 sdev = scsi_alloc_sdev(starget, 0, NULL); 1292 if (!sdev) 1293 return 0; 1294 if (scsi_device_get(sdev)) { 1295 __scsi_remove_device(sdev); 1296 return 0; 1297 } 1298 } 1299 1300 sprintf(devname, "host %d channel %d id %d", 1301 shost->host_no, sdev->channel, sdev->id); 1302 1303 /* 1304 * Allocate enough to hold the header (the same size as one scsi_lun) 1305 * plus the max number of luns we are requesting. 1306 * 1307 * Reallocating and trying again (with the exact amount we need) 1308 * would be nice, but then we need to somehow limit the size 1309 * allocated based on the available memory and the limits of 1310 * kmalloc - we don't want a kmalloc() failure of a huge value to 1311 * prevent us from finding any LUNs on this target. 1312 */ 1313 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun); 1314 lun_data = kmalloc(length, GFP_ATOMIC | 1315 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0)); 1316 if (!lun_data) { 1317 printk(ALLOC_FAILURE_MSG, __func__); 1318 goto out; 1319 } 1320 1321 scsi_cmd[0] = REPORT_LUNS; 1322 1323 /* 1324 * bytes 1 - 5: reserved, set to zero. 1325 */ 1326 memset(&scsi_cmd[1], 0, 5); 1327 1328 /* 1329 * bytes 6 - 9: length of the command. 1330 */ 1331 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff; 1332 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff; 1333 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff; 1334 scsi_cmd[9] = (unsigned char) length & 0xff; 1335 1336 scsi_cmd[10] = 0; /* reserved */ 1337 scsi_cmd[11] = 0; /* control */ 1338 1339 /* 1340 * We can get a UNIT ATTENTION, for example a power on/reset, so 1341 * retry a few times (like sd.c does for TEST UNIT READY). 1342 * Experience shows some combinations of adapter/devices get at 1343 * least two power on/resets. 1344 * 1345 * Illegal requests (for devices that do not support REPORT LUNS) 1346 * should come through as a check condition, and will not generate 1347 * a retry. 1348 */ 1349 for (retries = 0; retries < 3; retries++) { 1350 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending" 1351 " REPORT LUNS to %s (try %d)\n", devname, 1352 retries)); 1353 1354 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, 1355 lun_data, length, &sshdr, 1356 SCSI_TIMEOUT + 4 * HZ, 3, NULL); 1357 1358 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS" 1359 " %s (try %d) result 0x%x\n", result 1360 ? "failed" : "successful", retries, result)); 1361 if (result == 0) 1362 break; 1363 else if (scsi_sense_valid(&sshdr)) { 1364 if (sshdr.sense_key != UNIT_ATTENTION) 1365 break; 1366 } 1367 } 1368 1369 if (result) { 1370 /* 1371 * The device probably does not support a REPORT LUN command 1372 */ 1373 ret = 1; 1374 goto out_err; 1375 } 1376 1377 /* 1378 * Get the length from the first four bytes of lun_data. 1379 */ 1380 data = (u8 *) lun_data->scsi_lun; 1381 length = ((data[0] << 24) | (data[1] << 16) | 1382 (data[2] << 8) | (data[3] << 0)); 1383 1384 num_luns = (length / sizeof(struct scsi_lun)); 1385 if (num_luns > max_scsi_report_luns) { 1386 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)" 1387 " of %d luns reported, try increasing" 1388 " max_scsi_report_luns.\n", devname, 1389 max_scsi_report_luns, num_luns); 1390 num_luns = max_scsi_report_luns; 1391 } 1392 1393 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, 1394 "scsi scan: REPORT LUN scan\n")); 1395 1396 /* 1397 * Scan the luns in lun_data. The entry at offset 0 is really 1398 * the header, so start at 1 and go up to and including num_luns. 1399 */ 1400 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { 1401 lun = scsilun_to_int(lunp); 1402 1403 /* 1404 * Check if the unused part of lunp is non-zero, and so 1405 * does not fit in lun. 1406 */ 1407 if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) { 1408 int i; 1409 1410 /* 1411 * Output an error displaying the LUN in byte order, 1412 * this differs from what linux would print for the 1413 * integer LUN value. 1414 */ 1415 printk(KERN_WARNING "scsi: %s lun 0x", devname); 1416 data = (char *)lunp->scsi_lun; 1417 for (i = 0; i < sizeof(struct scsi_lun); i++) 1418 printk("%02x", data[i]); 1419 printk(" has a LUN larger than currently supported.\n"); 1420 } else if (lun > sdev->host->max_lun) { 1421 printk(KERN_WARNING "scsi: %s lun%d has a LUN larger" 1422 " than allowed by the host adapter\n", 1423 devname, lun); 1424 } else { 1425 int res; 1426 1427 res = scsi_probe_and_add_lun(starget, 1428 lun, NULL, NULL, rescan, NULL); 1429 if (res == SCSI_SCAN_NO_RESPONSE) { 1430 /* 1431 * Got some results, but now none, abort. 1432 */ 1433 sdev_printk(KERN_ERR, sdev, 1434 "Unexpected response" 1435 " from lun %d while scanning, scan" 1436 " aborted\n", lun); 1437 break; 1438 } 1439 } 1440 } 1441 1442 out_err: 1443 kfree(lun_data); 1444 out: 1445 scsi_device_put(sdev); 1446 if (scsi_device_created(sdev)) 1447 /* 1448 * the sdev we used didn't appear in the report luns scan 1449 */ 1450 __scsi_remove_device(sdev); 1451 return ret; 1452} 1453 1454struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, 1455 uint id, uint lun, void *hostdata) 1456{ 1457 struct scsi_device *sdev = ERR_PTR(-ENODEV); 1458 struct device *parent = &shost->shost_gendev; 1459 struct scsi_target *starget; 1460 1461 if (strncmp(scsi_scan_type, "none", 4) == 0) 1462 return ERR_PTR(-ENODEV); 1463 1464 starget = scsi_alloc_target(parent, channel, id); 1465 if (!starget) 1466 return ERR_PTR(-ENOMEM); 1467 scsi_autopm_get_target(starget); 1468 1469 mutex_lock(&shost->scan_mutex); 1470 if (!shost->async_scan) 1471 scsi_complete_async_scans(); 1472 1473 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1474 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); 1475 scsi_autopm_put_host(shost); 1476 } 1477 mutex_unlock(&shost->scan_mutex); 1478 scsi_autopm_put_target(starget); 1479 scsi_target_reap(starget); 1480 put_device(&starget->dev); 1481 1482 return sdev; 1483} 1484EXPORT_SYMBOL(__scsi_add_device); 1485 1486int scsi_add_device(struct Scsi_Host *host, uint channel, 1487 uint target, uint lun) 1488{ 1489 struct scsi_device *sdev = 1490 __scsi_add_device(host, channel, target, lun, NULL); 1491 if (IS_ERR(sdev)) 1492 return PTR_ERR(sdev); 1493 1494 scsi_device_put(sdev); 1495 return 0; 1496} 1497EXPORT_SYMBOL(scsi_add_device); 1498 1499void scsi_rescan_device(struct device *dev) 1500{ 1501 struct scsi_driver *drv; 1502 1503 if (!dev->driver) 1504 return; 1505 1506 drv = to_scsi_driver(dev->driver); 1507 if (try_module_get(drv->owner)) { 1508 if (drv->rescan) 1509 drv->rescan(dev); 1510 module_put(drv->owner); 1511 } 1512} 1513EXPORT_SYMBOL(scsi_rescan_device); 1514 1515static void __scsi_scan_target(struct device *parent, unsigned int channel, 1516 unsigned int id, unsigned int lun, int rescan) 1517{ 1518 struct Scsi_Host *shost = dev_to_shost(parent); 1519 int bflags = 0; 1520 int res; 1521 struct scsi_target *starget; 1522 1523 if (shost->this_id == id) 1524 /* 1525 * Don't scan the host adapter 1526 */ 1527 return; 1528 1529 starget = scsi_alloc_target(parent, channel, id); 1530 if (!starget) 1531 return; 1532 scsi_autopm_get_target(starget); 1533 1534 if (lun != SCAN_WILD_CARD) { 1535 /* 1536 * Scan for a specific host/chan/id/lun. 1537 */ 1538 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); 1539 goto out_reap; 1540 } 1541 1542 /* 1543 * Scan LUN 0, if there is some response, scan further. Ideally, we 1544 * would not configure LUN 0 until all LUNs are scanned. 1545 */ 1546 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); 1547 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { 1548 if (scsi_report_lun_scan(starget, bflags, rescan) != 0) 1549 /* 1550 * The REPORT LUN did not scan the target, 1551 * do a sequential scan. 1552 */ 1553 scsi_sequential_lun_scan(starget, bflags, 1554 starget->scsi_level, rescan); 1555 } 1556 1557 out_reap: 1558 scsi_autopm_put_target(starget); 1559 /* now determine if the target has any children at all 1560 * and if not, nuke it */ 1561 scsi_target_reap(starget); 1562 1563 put_device(&starget->dev); 1564} 1565 1566/** 1567 * scsi_scan_target - scan a target id, possibly including all LUNs on the target. 1568 * @parent: host to scan 1569 * @channel: channel to scan 1570 * @id: target id to scan 1571 * @lun: Specific LUN to scan or SCAN_WILD_CARD 1572 * @rescan: passed to LUN scanning routines 1573 * 1574 * Description: 1575 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, 1576 * and possibly all LUNs on the target id. 1577 * 1578 * First try a REPORT LUN scan, if that does not scan the target, do a 1579 * sequential scan of LUNs on the target id. 1580 **/ 1581void scsi_scan_target(struct device *parent, unsigned int channel, 1582 unsigned int id, unsigned int lun, int rescan) 1583{ 1584 struct Scsi_Host *shost = dev_to_shost(parent); 1585 1586 if (strncmp(scsi_scan_type, "none", 4) == 0) 1587 return; 1588 1589 mutex_lock(&shost->scan_mutex); 1590 if (!shost->async_scan) 1591 scsi_complete_async_scans(); 1592 1593 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1594 __scsi_scan_target(parent, channel, id, lun, rescan); 1595 scsi_autopm_put_host(shost); 1596 } 1597 mutex_unlock(&shost->scan_mutex); 1598} 1599EXPORT_SYMBOL(scsi_scan_target); 1600 1601static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, 1602 unsigned int id, unsigned int lun, int rescan) 1603{ 1604 uint order_id; 1605 1606 if (id == SCAN_WILD_CARD) 1607 for (id = 0; id < shost->max_id; ++id) { 1608 if (shost->reverse_ordering) 1609 /* 1610 * Scan from high to low id. 1611 */ 1612 order_id = shost->max_id - id - 1; 1613 else 1614 order_id = id; 1615 __scsi_scan_target(&shost->shost_gendev, channel, 1616 order_id, lun, rescan); 1617 } 1618 else 1619 __scsi_scan_target(&shost->shost_gendev, channel, 1620 id, lun, rescan); 1621} 1622 1623int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, 1624 unsigned int id, unsigned int lun, int rescan) 1625{ 1626 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, 1627 "%s: <%u:%u:%u>\n", 1628 __func__, channel, id, lun)); 1629 1630 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || 1631 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || 1632 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun))) 1633 return -EINVAL; 1634 1635 mutex_lock(&shost->scan_mutex); 1636 if (!shost->async_scan) 1637 scsi_complete_async_scans(); 1638 1639 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { 1640 if (channel == SCAN_WILD_CARD) 1641 for (channel = 0; channel <= shost->max_channel; 1642 channel++) 1643 scsi_scan_channel(shost, channel, id, lun, 1644 rescan); 1645 else 1646 scsi_scan_channel(shost, channel, id, lun, rescan); 1647 scsi_autopm_put_host(shost); 1648 } 1649 mutex_unlock(&shost->scan_mutex); 1650 1651 return 0; 1652} 1653 1654static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 1655{ 1656 struct scsi_device *sdev; 1657 shost_for_each_device(sdev, shost) { 1658 if (!scsi_host_scan_allowed(shost) || 1659 scsi_sysfs_add_sdev(sdev) != 0) 1660 __scsi_remove_device(sdev); 1661 } 1662} 1663 1664/** 1665 * scsi_prep_async_scan - prepare for an async scan 1666 * @shost: the host which will be scanned 1667 * Returns: a cookie to be passed to scsi_finish_async_scan() 1668 * 1669 * Tells the midlayer this host is going to do an asynchronous scan. 1670 * It reserves the host's position in the scanning list and ensures 1671 * that other asynchronous scans started after this one won't affect the 1672 * ordering of the discovered devices. 1673 */ 1674static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 1675{ 1676 struct async_scan_data *data; 1677 unsigned long flags; 1678 1679 if (strncmp(scsi_scan_type, "sync", 4) == 0) 1680 return NULL; 1681 1682 if (shost->async_scan) { 1683 printk("%s called twice for host %d", __func__, 1684 shost->host_no); 1685 dump_stack(); 1686 return NULL; 1687 } 1688 1689 data = kmalloc(sizeof(*data), GFP_KERNEL); 1690 if (!data) 1691 goto err; 1692 data->shost = scsi_host_get(shost); 1693 if (!data->shost) 1694 goto err; 1695 init_completion(&data->prev_finished); 1696 1697 mutex_lock(&shost->scan_mutex); 1698 spin_lock_irqsave(shost->host_lock, flags); 1699 shost->async_scan = 1; 1700 spin_unlock_irqrestore(shost->host_lock, flags); 1701 mutex_unlock(&shost->scan_mutex); 1702 1703 spin_lock(&async_scan_lock); 1704 if (list_empty(&scanning_hosts)) 1705 complete(&data->prev_finished); 1706 list_add_tail(&data->list, &scanning_hosts); 1707 spin_unlock(&async_scan_lock); 1708 1709 return data; 1710 1711 err: 1712 kfree(data); 1713 return NULL; 1714} 1715 1716/** 1717 * scsi_finish_async_scan - asynchronous scan has finished 1718 * @data: cookie returned from earlier call to scsi_prep_async_scan() 1719 * 1720 * All the devices currently attached to this host have been found. 1721 * This function announces all the devices it has found to the rest 1722 * of the system. 1723 */ 1724static void scsi_finish_async_scan(struct async_scan_data *data) 1725{ 1726 struct Scsi_Host *shost; 1727 unsigned long flags; 1728 1729 if (!data) 1730 return; 1731 1732 shost = data->shost; 1733 1734 mutex_lock(&shost->scan_mutex); 1735 1736 if (!shost->async_scan) { 1737 printk("%s called twice for host %d", __func__, 1738 shost->host_no); 1739 dump_stack(); 1740 mutex_unlock(&shost->scan_mutex); 1741 return; 1742 } 1743 1744 wait_for_completion(&data->prev_finished); 1745 1746 scsi_sysfs_add_devices(shost); 1747 1748 spin_lock_irqsave(shost->host_lock, flags); 1749 shost->async_scan = 0; 1750 spin_unlock_irqrestore(shost->host_lock, flags); 1751 1752 mutex_unlock(&shost->scan_mutex); 1753 1754 spin_lock(&async_scan_lock); 1755 list_del(&data->list); 1756 if (!list_empty(&scanning_hosts)) { 1757 struct async_scan_data *next = list_entry(scanning_hosts.next, 1758 struct async_scan_data, list); 1759 complete(&next->prev_finished); 1760 } 1761 spin_unlock(&async_scan_lock); 1762 1763 scsi_host_put(shost); 1764 kfree(data); 1765} 1766 1767static void do_scsi_scan_host(struct Scsi_Host *shost) 1768{ 1769 if (shost->hostt->scan_finished) { 1770 unsigned long start = jiffies; 1771 if (shost->hostt->scan_start) 1772 shost->hostt->scan_start(shost); 1773 1774 while (!shost->hostt->scan_finished(shost, jiffies - start)) 1775 msleep(10); 1776 } else { 1777 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, 1778 SCAN_WILD_CARD, 0); 1779 } 1780} 1781 1782static int do_scan_async(void *_data) 1783{ 1784 struct async_scan_data *data = _data; 1785 struct Scsi_Host *shost = data->shost; 1786 1787 do_scsi_scan_host(shost); 1788 scsi_finish_async_scan(data); 1789 scsi_autopm_put_host(shost); 1790 return 0; 1791} 1792 1793/** 1794 * scsi_scan_host - scan the given adapter 1795 * @shost: adapter to scan 1796 **/ 1797void scsi_scan_host(struct Scsi_Host *shost) 1798{ 1799 struct task_struct *p; 1800 struct async_scan_data *data; 1801 1802 if (strncmp(scsi_scan_type, "none", 4) == 0) 1803 return; 1804 if (scsi_autopm_get_host(shost) < 0) 1805 return; 1806 1807 data = scsi_prep_async_scan(shost); 1808 if (!data) { 1809 do_scsi_scan_host(shost); 1810 scsi_autopm_put_host(shost); 1811 return; 1812 } 1813 1814 p = kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no); 1815 if (IS_ERR(p)) 1816 do_scan_async(data); 1817 /* scsi_autopm_put_host(shost) is called in do_scan_async() */ 1818} 1819EXPORT_SYMBOL(scsi_scan_host); 1820 1821void scsi_forget_host(struct Scsi_Host *shost) 1822{ 1823 struct scsi_device *sdev; 1824 unsigned long flags; 1825 1826 restart: 1827 spin_lock_irqsave(shost->host_lock, flags); 1828 list_for_each_entry(sdev, &shost->__devices, siblings) { 1829 if (sdev->sdev_state == SDEV_DEL) 1830 continue; 1831 spin_unlock_irqrestore(shost->host_lock, flags); 1832 __scsi_remove_device(sdev); 1833 goto restart; 1834 } 1835 spin_unlock_irqrestore(shost->host_lock, flags); 1836} 1837 1838/** 1839 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself 1840 * @shost: Host that needs a scsi_device 1841 * 1842 * Lock status: None assumed. 1843 * 1844 * Returns: The scsi_device or NULL 1845 * 1846 * Notes: 1847 * Attach a single scsi_device to the Scsi_Host - this should 1848 * be made to look like a "pseudo-device" that points to the 1849 * HA itself. 1850 * 1851 * Note - this device is not accessible from any high-level 1852 * drivers (including generics), which is probably not 1853 * optimal. We can add hooks later to attach. 1854 */ 1855struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) 1856{ 1857 struct scsi_device *sdev = NULL; 1858 struct scsi_target *starget; 1859 1860 mutex_lock(&shost->scan_mutex); 1861 if (!scsi_host_scan_allowed(shost)) 1862 goto out; 1863 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); 1864 if (!starget) 1865 goto out; 1866 1867 sdev = scsi_alloc_sdev(starget, 0, NULL); 1868 if (sdev) 1869 sdev->borken = 0; 1870 else 1871 scsi_target_reap(starget); 1872 put_device(&starget->dev); 1873 out: 1874 mutex_unlock(&shost->scan_mutex); 1875 return sdev; 1876} 1877EXPORT_SYMBOL(scsi_get_host_dev); 1878 1879/** 1880 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself 1881 * @sdev: Host device to be freed 1882 * 1883 * Lock status: None assumed. 1884 * 1885 * Returns: Nothing 1886 */ 1887void scsi_free_host_dev(struct scsi_device *sdev) 1888{ 1889 BUG_ON(sdev->id != sdev->host->this_id); 1890 1891 __scsi_remove_device(sdev); 1892} 1893EXPORT_SYMBOL(scsi_free_host_dev); 1894