4 * Copyright (C) 2000 Eric Youngdale,
5 * Copyright (C) 2002 Patrick Mansfield
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.
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.
14 * For every id of every channel on the given host:
16 * Scan LUN 0; if the target responds to LUN 0 (even if there is no
17 * device or storage attached to LUN 0):
19 * If LUN 0 has a device attached, allocate and setup a
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.
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>
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>
47 #include "scsi_priv.h"
48 #include "scsi_logging.h"
50 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
51 " SCSI scanning, some SCSI devices might not be configured\n"
56 #define SCSI_TIMEOUT (2*HZ)
59 * Prefix values for the SCSI id's (stored in sysfs name field)
61 #define SCSI_UID_SER_NUM 'S'
62 #define SCSI_UID_UNKNOWN 'Z'
65 * Return values of some of the scanning functions.
67 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
68 * includes allocation or general failures preventing IO from being sent.
70 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
73 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
76 #define SCSI_SCAN_NO_RESPONSE 0
77 #define SCSI_SCAN_TARGET_PRESENT 1
78 #define SCSI_SCAN_LUN_PRESENT 2
80 static const char *scsi_null_device_strs = "nullnullnullnull";
82 #define MAX_SCSI_LUNS 512
84 static u64 max_scsi_luns = MAX_SCSI_LUNS;
86 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR);
87 MODULE_PARM_DESC(max_luns,
88 "last scsi LUN (should be between 1 and 2^64-1)");
90 #ifdef CONFIG_SCSI_SCAN_ASYNC
91 #define SCSI_SCAN_TYPE_DEFAULT "async"
93 #define SCSI_SCAN_TYPE_DEFAULT "sync"
96 char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT;
98 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
99 MODULE_PARM_DESC(scan, "sync, async or none");
102 * max_scsi_report_luns: the maximum number of LUNS that will be
103 * returned from the REPORT LUNS command. 8 times this value must
104 * be allocated. In theory this could be up to an 8 byte value, but
105 * in practice, the maximum number of LUNs suppored by any device
108 static unsigned int max_scsi_report_luns = 511;
110 module_param_named(max_report_luns, max_scsi_report_luns, uint, S_IRUGO|S_IWUSR);
111 MODULE_PARM_DESC(max_report_luns,
112 "REPORT LUNS maximum number of LUNS received (should be"
113 " between 1 and 16384)");
115 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
117 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
118 MODULE_PARM_DESC(inq_timeout,
119 "Timeout (in seconds) waiting for devices to answer INQUIRY."
120 " Default is 20. Some devices may need more; most need less.");
122 /* This lock protects only this list */
123 static DEFINE_SPINLOCK(async_scan_lock);
124 static LIST_HEAD(scanning_hosts);
126 struct async_scan_data {
127 struct list_head list;
128 struct Scsi_Host *shost;
129 struct completion prev_finished;
133 * scsi_complete_async_scans - Wait for asynchronous scans to complete
135 * When this function returns, any host which started scanning before
136 * this function was called will have finished its scan. Hosts which
137 * started scanning after this function was called may or may not have
140 int scsi_complete_async_scans(void)
142 struct async_scan_data *data;
145 if (list_empty(&scanning_hosts))
147 /* If we can't get memory immediately, that's OK. Just
148 * sleep a little. Even if we never get memory, the async
149 * scans will finish eventually.
151 data = kmalloc(sizeof(*data), GFP_KERNEL);
157 init_completion(&data->prev_finished);
159 spin_lock(&async_scan_lock);
160 /* Check that there's still somebody else on the list */
161 if (list_empty(&scanning_hosts))
163 list_add_tail(&data->list, &scanning_hosts);
164 spin_unlock(&async_scan_lock);
166 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
167 wait_for_completion(&data->prev_finished);
169 spin_lock(&async_scan_lock);
170 list_del(&data->list);
171 if (!list_empty(&scanning_hosts)) {
172 struct async_scan_data *next = list_entry(scanning_hosts.next,
173 struct async_scan_data, list);
174 complete(&next->prev_finished);
177 spin_unlock(&async_scan_lock);
184 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
185 * @sdev: scsi device to send command to
186 * @result: area to store the result of the MODE SENSE
189 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
190 * Called for BLIST_KEY devices.
192 static void scsi_unlock_floptical(struct scsi_device *sdev,
193 unsigned char *result)
195 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
197 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n");
198 scsi_cmd[0] = MODE_SENSE;
202 scsi_cmd[4] = 0x2a; /* size */
204 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
205 SCSI_TIMEOUT, 3, NULL);
209 * scsi_alloc_sdev - allocate and setup a scsi_Device
210 * @starget: which target to allocate a &scsi_device for
212 * @hostdata: usually NULL and set by ->slave_alloc instead
215 * Allocate, initialize for io, and return a pointer to a scsi_Device.
216 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
217 * adds scsi_Device to the appropriate list.
220 * scsi_Device pointer, or NULL on failure.
222 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
223 u64 lun, void *hostdata)
225 struct scsi_device *sdev;
226 int display_failure_msg = 1, ret;
227 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
228 extern void scsi_evt_thread(struct work_struct *work);
229 extern void scsi_requeue_run_queue(struct work_struct *work);
231 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
236 sdev->vendor = scsi_null_device_strs;
237 sdev->model = scsi_null_device_strs;
238 sdev->rev = scsi_null_device_strs;
240 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
241 sdev->id = starget->id;
243 sdev->channel = starget->channel;
244 sdev->sdev_state = SDEV_CREATED;
245 INIT_LIST_HEAD(&sdev->siblings);
246 INIT_LIST_HEAD(&sdev->same_target_siblings);
247 INIT_LIST_HEAD(&sdev->cmd_list);
248 INIT_LIST_HEAD(&sdev->starved_entry);
249 INIT_LIST_HEAD(&sdev->event_list);
250 spin_lock_init(&sdev->list_lock);
251 INIT_WORK(&sdev->event_work, scsi_evt_thread);
252 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
254 sdev->sdev_gendev.parent = get_device(&starget->dev);
255 sdev->sdev_target = starget;
257 /* usually NULL and set by ->slave_alloc instead */
258 sdev->hostdata = hostdata;
260 /* if the device needs this changing, it may do so in the
261 * slave_configure function */
262 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
265 * Some low level driver could use device->type
270 * Assume that the device will have handshaking problems,
271 * and then fix this field later if it turns out it
276 if (shost_use_blk_mq(shost))
277 sdev->request_queue = scsi_mq_alloc_queue(sdev);
279 sdev->request_queue = scsi_alloc_queue(sdev);
280 if (!sdev->request_queue) {
281 /* release fn is set up in scsi_sysfs_device_initialise, so
282 * have to free and put manually here */
283 put_device(&starget->dev);
287 WARN_ON_ONCE(!blk_get_queue(sdev->request_queue));
288 sdev->request_queue->queuedata = sdev;
290 if (!shost_use_blk_mq(sdev->host) &&
291 (shost->bqt || shost->hostt->use_blk_tags)) {
292 blk_queue_init_tags(sdev->request_queue,
293 sdev->host->cmd_per_lun, shost->bqt,
294 shost->hostt->tag_alloc_policy);
296 scsi_change_queue_depth(sdev, sdev->host->cmd_per_lun);
298 scsi_sysfs_device_initialize(sdev);
300 if (shost->hostt->slave_alloc) {
301 ret = shost->hostt->slave_alloc(sdev);
304 * if LLDD reports slave not present, don't clutter
305 * console with alloc failure messages
308 display_failure_msg = 0;
309 goto out_device_destroy;
316 __scsi_remove_device(sdev);
318 if (display_failure_msg)
319 printk(ALLOC_FAILURE_MSG, __func__);
323 static void scsi_target_destroy(struct scsi_target *starget)
325 struct device *dev = &starget->dev;
326 struct Scsi_Host *shost = dev_to_shost(dev->parent);
329 starget->state = STARGET_DEL;
330 transport_destroy_device(dev);
331 spin_lock_irqsave(shost->host_lock, flags);
332 if (shost->hostt->target_destroy)
333 shost->hostt->target_destroy(starget);
334 list_del_init(&starget->siblings);
335 spin_unlock_irqrestore(shost->host_lock, flags);
339 static void scsi_target_dev_release(struct device *dev)
341 struct device *parent = dev->parent;
342 struct scsi_target *starget = to_scsi_target(dev);
348 static struct device_type scsi_target_type = {
349 .name = "scsi_target",
350 .release = scsi_target_dev_release,
353 int scsi_is_target_device(const struct device *dev)
355 return dev->type == &scsi_target_type;
357 EXPORT_SYMBOL(scsi_is_target_device);
359 static struct scsi_target *__scsi_find_target(struct device *parent,
360 int channel, uint id)
362 struct scsi_target *starget, *found_starget = NULL;
363 struct Scsi_Host *shost = dev_to_shost(parent);
365 * Search for an existing target for this sdev.
367 list_for_each_entry(starget, &shost->__targets, siblings) {
368 if (starget->id == id &&
369 starget->channel == channel) {
370 found_starget = starget;
375 get_device(&found_starget->dev);
377 return found_starget;
381 * scsi_target_reap_ref_release - remove target from visibility
382 * @kref: the reap_ref in the target being released
384 * Called on last put of reap_ref, which is the indication that no device
385 * under this target is visible anymore, so render the target invisible in
386 * sysfs. Note: we have to be in user context here because the target reaps
387 * should be done in places where the scsi device visibility is being removed.
389 static void scsi_target_reap_ref_release(struct kref *kref)
391 struct scsi_target *starget
392 = container_of(kref, struct scsi_target, reap_ref);
395 * if we get here and the target is still in the CREATED state that
396 * means it was allocated but never made visible (because a scan
397 * turned up no LUNs), so don't call device_del() on it.
399 if (starget->state != STARGET_CREATED) {
400 transport_remove_device(&starget->dev);
401 device_del(&starget->dev);
403 scsi_target_destroy(starget);
406 static void scsi_target_reap_ref_put(struct scsi_target *starget)
408 kref_put(&starget->reap_ref, scsi_target_reap_ref_release);
412 * scsi_alloc_target - allocate a new or find an existing target
413 * @parent: parent of the target (need not be a scsi host)
414 * @channel: target channel number (zero if no channels)
415 * @id: target id number
417 * Return an existing target if one exists, provided it hasn't already
418 * gone into STARGET_DEL state, otherwise allocate a new target.
420 * The target is returned with an incremented reference, so the caller
421 * is responsible for both reaping and doing a last put
423 static struct scsi_target *scsi_alloc_target(struct device *parent,
424 int channel, uint id)
426 struct Scsi_Host *shost = dev_to_shost(parent);
427 struct device *dev = NULL;
429 const int size = sizeof(struct scsi_target)
430 + shost->transportt->target_size;
431 struct scsi_target *starget;
432 struct scsi_target *found_target;
435 starget = kzalloc(size, GFP_KERNEL);
437 printk(KERN_ERR "%s: allocation failure\n", __func__);
441 device_initialize(dev);
442 kref_init(&starget->reap_ref);
443 dev->parent = get_device(parent);
444 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
445 dev->bus = &scsi_bus_type;
446 dev->type = &scsi_target_type;
448 starget->channel = channel;
449 starget->can_queue = 0;
450 INIT_LIST_HEAD(&starget->siblings);
451 INIT_LIST_HEAD(&starget->devices);
452 starget->state = STARGET_CREATED;
453 starget->scsi_level = SCSI_2;
454 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
456 spin_lock_irqsave(shost->host_lock, flags);
458 found_target = __scsi_find_target(parent, channel, id);
462 list_add_tail(&starget->siblings, &shost->__targets);
463 spin_unlock_irqrestore(shost->host_lock, flags);
464 /* allocate and add */
465 transport_setup_device(dev);
466 if (shost->hostt->target_alloc) {
467 error = shost->hostt->target_alloc(starget);
470 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
471 /* don't want scsi_target_reap to do the final
472 * put because it will be under the host lock */
473 scsi_target_destroy(starget);
483 * release routine already fired if kref is zero, so if we can still
484 * take the reference, the target must be alive. If we can't, it must
485 * be dying and we need to wait for a new target
487 ref_got = kref_get_unless_zero(&found_target->reap_ref);
489 spin_unlock_irqrestore(shost->host_lock, flags);
495 * Unfortunately, we found a dying target; need to wait until it's
496 * dead before we can get a new one. There is an anomaly here. We
497 * *should* call scsi_target_reap() to balance the kref_get() of the
498 * reap_ref above. However, since the target being released, it's
499 * already invisible and the reap_ref is irrelevant. If we call
500 * scsi_target_reap() we might spuriously do another device_del() on
501 * an already invisible target.
503 put_device(&found_target->dev);
505 * length of time is irrelevant here, we just want to yield the CPU
506 * for a tick to avoid busy waiting for the target to die.
513 * scsi_target_reap - check to see if target is in use and destroy if not
514 * @starget: target to be checked
516 * This is used after removing a LUN or doing a last put of the target
517 * it checks atomically that nothing is using the target and removes
520 void scsi_target_reap(struct scsi_target *starget)
523 * serious problem if this triggers: STARGET_DEL is only set in the if
524 * the reap_ref drops to zero, so we're trying to do another final put
525 * on an already released kref
527 BUG_ON(starget->state == STARGET_DEL);
528 scsi_target_reap_ref_put(starget);
532 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string
533 * @s: INQUIRY result string to sanitize
534 * @len: length of the string
537 * The SCSI spec says that INQUIRY vendor, product, and revision
538 * strings must consist entirely of graphic ASCII characters,
539 * padded on the right with spaces. Since not all devices obey
540 * this rule, we will replace non-graphic or non-ASCII characters
541 * with spaces. Exception: a NUL character is interpreted as a
542 * string terminator, so all the following characters are set to
545 static void sanitize_inquiry_string(unsigned char *s, int len)
549 for (; len > 0; (--len, ++s)) {
552 if (terminated || *s < 0x20 || *s > 0x7e)
558 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
559 * @sdev: scsi_device to probe
560 * @inq_result: area to store the INQUIRY result
561 * @result_len: len of inq_result
562 * @bflags: store any bflags found here
565 * Probe the lun associated with @req using a standard SCSI INQUIRY;
567 * If the INQUIRY is successful, zero is returned and the
568 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
569 * are copied to the scsi_device any flags value is stored in *@bflags.
571 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
572 int result_len, int *bflags)
574 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
575 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
576 int response_len = 0;
577 int pass, count, result;
578 struct scsi_sense_hdr sshdr;
582 /* Perform up to 3 passes. The first pass uses a conservative
583 * transfer length of 36 unless sdev->inquiry_len specifies a
584 * different value. */
585 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
586 try_inquiry_len = first_inquiry_len;
590 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
591 "scsi scan: INQUIRY pass %d length %d\n",
592 pass, try_inquiry_len));
594 /* Each pass gets up to three chances to ignore Unit Attention */
595 for (count = 0; count < 3; ++count) {
598 memset(scsi_cmd, 0, 6);
599 scsi_cmd[0] = INQUIRY;
600 scsi_cmd[4] = (unsigned char) try_inquiry_len;
602 memset(inq_result, 0, try_inquiry_len);
604 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
605 inq_result, try_inquiry_len, &sshdr,
606 HZ / 2 + HZ * scsi_inq_timeout, 3,
609 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
610 "scsi scan: INQUIRY %s with code 0x%x\n",
611 result ? "failed" : "successful", result));
615 * not-ready to ready transition [asc/ascq=0x28/0x0]
616 * or power-on, reset [asc/ascq=0x29/0x0], continue.
617 * INQUIRY should not yield UNIT_ATTENTION
618 * but many buggy devices do so anyway.
620 if ((driver_byte(result) & DRIVER_SENSE) &&
621 scsi_sense_valid(&sshdr)) {
622 if ((sshdr.sense_key == UNIT_ATTENTION) &&
623 ((sshdr.asc == 0x28) ||
624 (sshdr.asc == 0x29)) &&
630 * if nothing was transferred, we try
631 * again. It's a workaround for some USB
634 if (resid == try_inquiry_len)
641 sanitize_inquiry_string(&inq_result[8], 8);
642 sanitize_inquiry_string(&inq_result[16], 16);
643 sanitize_inquiry_string(&inq_result[32], 4);
645 response_len = inq_result[4] + 5;
646 if (response_len > 255)
647 response_len = first_inquiry_len; /* sanity */
650 * Get any flags for this device.
652 * XXX add a bflags to scsi_device, and replace the
653 * corresponding bit fields in scsi_device, so bflags
654 * need not be passed as an argument.
656 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
659 /* When the first pass succeeds we gain information about
660 * what larger transfer lengths might work. */
662 if (BLIST_INQUIRY_36 & *bflags)
663 next_inquiry_len = 36;
664 else if (BLIST_INQUIRY_58 & *bflags)
665 next_inquiry_len = 58;
666 else if (sdev->inquiry_len)
667 next_inquiry_len = sdev->inquiry_len;
669 next_inquiry_len = response_len;
671 /* If more data is available perform the second pass */
672 if (next_inquiry_len > try_inquiry_len) {
673 try_inquiry_len = next_inquiry_len;
679 } else if (pass == 2) {
680 sdev_printk(KERN_INFO, sdev,
681 "scsi scan: %d byte inquiry failed. "
682 "Consider BLIST_INQUIRY_36 for this device\n",
685 /* If this pass failed, the third pass goes back and transfers
686 * the same amount as we successfully got in the first pass. */
687 try_inquiry_len = first_inquiry_len;
692 /* If the last transfer attempt got an error, assume the
693 * peripheral doesn't exist or is dead. */
697 /* Don't report any more data than the device says is valid */
698 sdev->inquiry_len = min(try_inquiry_len, response_len);
701 * XXX Abort if the response length is less than 36? If less than
702 * 32, the lookup of the device flags (above) could be invalid,
703 * and it would be possible to take an incorrect action - we do
704 * not want to hang because of a short INQUIRY. On the flip side,
705 * if the device is spun down or becoming ready (and so it gives a
706 * short INQUIRY), an abort here prevents any further use of the
707 * device, including spin up.
709 * On the whole, the best approach seems to be to assume the first
710 * 36 bytes are valid no matter what the device says. That's
711 * better than copying < 36 bytes to the inquiry-result buffer
712 * and displaying garbage for the Vendor, Product, or Revision
715 if (sdev->inquiry_len < 36) {
716 sdev_printk(KERN_INFO, sdev,
717 "scsi scan: INQUIRY result too short (%d),"
718 " using 36\n", sdev->inquiry_len);
719 sdev->inquiry_len = 36;
723 * Related to the above issue:
725 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
726 * and if not ready, sent a START_STOP to start (maybe spin up) and
727 * then send the INQUIRY again, since the INQUIRY can change after
728 * a device is initialized.
730 * Ideally, start a device if explicitly asked to do so. This
731 * assumes that a device is spun up on power on, spun down on
732 * request, and then spun up on request.
736 * The scanning code needs to know the scsi_level, even if no
737 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
738 * non-zero LUNs can be scanned.
740 sdev->scsi_level = inq_result[2] & 0x07;
741 if (sdev->scsi_level >= 2 ||
742 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
744 sdev->sdev_target->scsi_level = sdev->scsi_level;
747 * If SCSI-2 or lower, and if the transport requires it,
748 * store the LUN value in CDB[1].
750 sdev->lun_in_cdb = 0;
751 if (sdev->scsi_level <= SCSI_2 &&
752 sdev->scsi_level != SCSI_UNKNOWN &&
753 !sdev->host->no_scsi2_lun_in_cdb)
754 sdev->lun_in_cdb = 1;
760 * scsi_add_lun - allocate and fully initialze a scsi_device
761 * @sdev: holds information to be stored in the new scsi_device
762 * @inq_result: holds the result of a previous INQUIRY to the LUN
763 * @bflags: black/white list flag
764 * @async: 1 if this device is being scanned asynchronously
767 * Initialize the scsi_device @sdev. Optionally set fields based
768 * on values in *@bflags.
771 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
772 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
774 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
775 int *bflags, int async)
780 * XXX do not save the inquiry, since it can change underneath us,
781 * save just vendor/model/rev.
783 * Rather than save it and have an ioctl that retrieves the saved
784 * value, have an ioctl that executes the same INQUIRY code used
785 * in scsi_probe_lun, let user level programs doing INQUIRY
786 * scanning run at their own risk, or supply a user level program
787 * that can correctly scan.
791 * Copy at least 36 bytes of INQUIRY data, so that we don't
792 * dereference unallocated memory when accessing the Vendor,
793 * Product, and Revision strings. Badly behaved devices may set
794 * the INQUIRY Additional Length byte to a small value, indicating
795 * these strings are invalid, but often they contain plausible data
796 * nonetheless. It doesn't matter if the device sent < 36 bytes
797 * total, since scsi_probe_lun() initializes inq_result with 0s.
799 sdev->inquiry = kmemdup(inq_result,
800 max_t(size_t, sdev->inquiry_len, 36),
802 if (sdev->inquiry == NULL)
803 return SCSI_SCAN_NO_RESPONSE;
805 sdev->vendor = (char *) (sdev->inquiry + 8);
806 sdev->model = (char *) (sdev->inquiry + 16);
807 sdev->rev = (char *) (sdev->inquiry + 32);
809 if (strncmp(sdev->vendor, "ATA ", 8) == 0) {
811 * sata emulation layer device. This is a hack to work around
812 * the SATL power management specifications which state that
813 * when the SATL detects the device has gone into standby
814 * mode, it shall respond with NOT READY.
816 sdev->allow_restart = 1;
819 if (*bflags & BLIST_ISROM) {
820 sdev->type = TYPE_ROM;
823 sdev->type = (inq_result[0] & 0x1f);
824 sdev->removable = (inq_result[1] & 0x80) >> 7;
827 * some devices may respond with wrong type for
828 * well-known logical units. Force well-known type
829 * to enumerate them correctly.
831 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) {
832 sdev_printk(KERN_WARNING, sdev,
833 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n",
834 __func__, sdev->type, (unsigned int)sdev->lun);
835 sdev->type = TYPE_WLUN;
840 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
841 /* RBC and MMC devices can return SCSI-3 compliance and yet
842 * still not support REPORT LUNS, so make them act as
843 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
844 * specifically set */
845 if ((*bflags & BLIST_REPORTLUN2) == 0)
846 *bflags |= BLIST_NOREPORTLUN;
850 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
851 * spec says: The device server is capable of supporting the
852 * specified peripheral device type on this logical unit. However,
853 * the physical device is not currently connected to this logical
856 * The above is vague, as it implies that we could treat 001 and
857 * 011 the same. Stay compatible with previous code, and create a
858 * scsi_device for a PQ of 1
860 * Don't set the device offline here; rather let the upper
861 * level drivers eval the PQ to decide whether they should
862 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
865 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
866 sdev->lockable = sdev->removable;
867 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
869 if (sdev->scsi_level >= SCSI_3 ||
870 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
872 if (inq_result[7] & 0x60)
874 if (inq_result[7] & 0x10)
877 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
878 "ANSI: %d%s\n", scsi_device_type(sdev->type),
879 sdev->vendor, sdev->model, sdev->rev,
880 sdev->inq_periph_qual, inq_result[2] & 0x07,
881 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
883 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
884 !(*bflags & BLIST_NOTQ)) {
885 sdev->tagged_supported = 1;
886 sdev->simple_tags = 1;
890 * Some devices (Texel CD ROM drives) have handshaking problems
891 * when used with the Seagate controllers. borken is initialized
892 * to 1, and then set it to 0 here.
894 if ((*bflags & BLIST_BORKEN) == 0)
897 if (*bflags & BLIST_NO_ULD_ATTACH)
898 sdev->no_uld_attach = 1;
901 * Apparently some really broken devices (contrary to the SCSI
902 * standards) need to be selected without asserting ATN
904 if (*bflags & BLIST_SELECT_NO_ATN)
905 sdev->select_no_atn = 1;
908 * Maximum 512 sector transfer length
909 * broken RA4x00 Compaq Disk Array
911 if (*bflags & BLIST_MAX_512)
912 blk_queue_max_hw_sectors(sdev->request_queue, 512);
915 * Some devices may not want to have a start command automatically
916 * issued when a device is added.
918 if (*bflags & BLIST_NOSTARTONADD)
919 sdev->no_start_on_add = 1;
921 if (*bflags & BLIST_SINGLELUN)
922 scsi_target(sdev)->single_lun = 1;
924 sdev->use_10_for_rw = 1;
926 if (*bflags & BLIST_MS_SKIP_PAGE_08)
927 sdev->skip_ms_page_8 = 1;
929 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
930 sdev->skip_ms_page_3f = 1;
932 if (*bflags & BLIST_USE_10_BYTE_MS)
933 sdev->use_10_for_ms = 1;
935 /* some devices don't like REPORT SUPPORTED OPERATION CODES
936 * and will simply timeout causing sd_mod init to take a very
938 if (*bflags & BLIST_NO_RSOC)
939 sdev->no_report_opcodes = 1;
941 /* set the device running here so that slave configure
943 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
945 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
948 sdev_printk(KERN_ERR, sdev,
949 "in wrong state %s to complete scan\n",
950 scsi_device_state_name(sdev->sdev_state));
951 return SCSI_SCAN_NO_RESPONSE;
955 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
956 sdev->use_192_bytes_for_3f = 1;
958 if (*bflags & BLIST_NOT_LOCKABLE)
961 if (*bflags & BLIST_RETRY_HWERROR)
962 sdev->retry_hwerror = 1;
964 if (*bflags & BLIST_NO_DIF)
967 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
969 if (*bflags & BLIST_TRY_VPD_PAGES)
970 sdev->try_vpd_pages = 1;
971 else if (*bflags & BLIST_SKIP_VPD_PAGES)
972 sdev->skip_vpd_pages = 1;
974 transport_configure_device(&sdev->sdev_gendev);
976 if (sdev->host->hostt->slave_configure) {
977 ret = sdev->host->hostt->slave_configure(sdev);
980 * if LLDD reports slave not present, don't clutter
981 * console with alloc failure messages
984 sdev_printk(KERN_ERR, sdev,
985 "failed to configure device\n");
987 return SCSI_SCAN_NO_RESPONSE;
991 if (sdev->scsi_level >= SCSI_3)
992 scsi_attach_vpd(sdev);
994 sdev->max_queue_depth = sdev->queue_depth;
997 * Ok, the device is now all set up, we can
998 * register it and tell the rest of the kernel
1001 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
1002 return SCSI_SCAN_NO_RESPONSE;
1004 return SCSI_SCAN_LUN_PRESENT;
1007 #ifdef CONFIG_SCSI_LOGGING
1009 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
1010 * @buf: Output buffer with at least end-first+1 bytes of space
1011 * @inq: Inquiry buffer (input)
1012 * @first: Offset of string into inq
1013 * @end: Index after last character in inq
1015 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
1016 unsigned first, unsigned end)
1018 unsigned term = 0, idx;
1020 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
1021 if (inq[idx+first] > ' ') {
1022 buf[idx] = inq[idx+first];
1034 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
1035 * @starget: pointer to target device structure
1036 * @lun: LUN of target device
1037 * @bflagsp: store bflags here if not NULL
1038 * @sdevp: probe the LUN corresponding to this scsi_device
1039 * @rescan: if nonzero skip some code only needed on first scan
1040 * @hostdata: passed to scsi_alloc_sdev()
1043 * Call scsi_probe_lun, if a LUN with an attached device is found,
1044 * allocate and set it up by calling scsi_add_lun.
1047 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1048 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1049 * attached at the LUN
1050 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1052 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1053 u64 lun, int *bflagsp,
1054 struct scsi_device **sdevp, int rescan,
1057 struct scsi_device *sdev;
1058 unsigned char *result;
1059 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1060 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1063 * The rescan flag is used as an optimization, the first scan of a
1064 * host adapter calls into here with rescan == 0.
1066 sdev = scsi_device_lookup_by_target(starget, lun);
1068 if (rescan || !scsi_device_created(sdev)) {
1069 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1070 "scsi scan: device exists on %s\n",
1071 dev_name(&sdev->sdev_gendev)));
1075 scsi_device_put(sdev);
1078 *bflagsp = scsi_get_device_flags(sdev,
1081 return SCSI_SCAN_LUN_PRESENT;
1083 scsi_device_put(sdev);
1085 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1089 result = kmalloc(result_len, GFP_ATOMIC |
1090 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
1094 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1095 goto out_free_result;
1100 * result contains valid SCSI INQUIRY data.
1102 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
1104 * For a Peripheral qualifier 3 (011b), the SCSI
1105 * spec says: The device server is not capable of
1106 * supporting a physical device on this logical
1109 * For disks, this implies that there is no
1110 * logical disk configured at sdev->lun, but there
1111 * is a target id responding.
1113 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1114 " peripheral qualifier of 3, device not"
1117 SCSI_LOG_SCAN_BUS(1, {
1118 unsigned char vend[9];
1119 unsigned char mod[17];
1121 sdev_printk(KERN_INFO, sdev,
1122 "scsi scan: consider passing scsi_mod."
1123 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1124 scsi_inq_str(vend, result, 8, 16),
1125 scsi_inq_str(mod, result, 16, 32));
1130 res = SCSI_SCAN_TARGET_PRESENT;
1131 goto out_free_result;
1135 * Some targets may set slight variations of PQ and PDT to signal
1136 * that no LUN is present, so don't add sdev in these cases.
1137 * Two specific examples are:
1138 * 1) NetApp targets: return PQ=1, PDT=0x1f
1139 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1140 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1143 * 1) SCSI SPC-3, pp. 145-146
1144 * PQ=1: "A peripheral device having the specified peripheral
1145 * device type is not connected to this logical unit. However, the
1146 * device server is capable of supporting the specified peripheral
1147 * device type on this logical unit."
1148 * PDT=0x1f: "Unknown or no device type"
1149 * 2) USB UFI 1.0, p. 20
1150 * PDT=00h Direct-access device (floppy)
1151 * PDT=1Fh none (no FDD connected to the requested logical unit)
1153 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1154 (result[0] & 0x1f) == 0x1f &&
1155 !scsi_is_wlun(lun)) {
1156 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1157 "scsi scan: peripheral device type"
1158 " of 31, no device added\n"));
1159 res = SCSI_SCAN_TARGET_PRESENT;
1160 goto out_free_result;
1163 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1164 if (res == SCSI_SCAN_LUN_PRESENT) {
1165 if (bflags & BLIST_KEY) {
1167 scsi_unlock_floptical(sdev, result);
1174 if (res == SCSI_SCAN_LUN_PRESENT) {
1176 if (scsi_device_get(sdev) == 0) {
1179 __scsi_remove_device(sdev);
1180 res = SCSI_SCAN_NO_RESPONSE;
1184 __scsi_remove_device(sdev);
1190 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1191 * @starget: pointer to target structure to scan
1192 * @bflags: black/white list flag for LUN 0
1193 * @scsi_level: Which version of the standard does this device adhere to
1194 * @rescan: passed to scsi_probe_add_lun()
1197 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1198 * scanned) to some maximum lun until a LUN is found with no device
1199 * attached. Use the bflags to figure out any oddities.
1201 * Modifies sdevscan->lun.
1203 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1204 int bflags, int scsi_level, int rescan)
1207 u64 sparse_lun, lun;
1208 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1210 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget,
1211 "scsi scan: Sequential scan\n"));
1213 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1215 * If this device is known to support sparse multiple units,
1216 * override the other settings, and scan all of them. Normally,
1217 * SCSI-3 devices should be scanned via the REPORT LUNS.
1219 if (bflags & BLIST_SPARSELUN) {
1220 max_dev_lun = shost->max_lun;
1226 * If less than SCSI_1_CCS, and no special lun scanning, stop
1227 * scanning; this matches 2.4 behaviour, but could just be a bug
1228 * (to continue scanning a SCSI_1_CCS device).
1230 * This test is broken. We might not have any device on lun0 for
1231 * a sparselun device, and if that's the case then how would we
1232 * know the real scsi_level, eh? It might make sense to just not
1233 * scan any SCSI_1 device for non-0 luns, but that check would best
1234 * go into scsi_alloc_sdev() and just have it return null when asked
1235 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1237 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1238 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1243 * If this device is known to support multiple units, override
1244 * the other settings, and scan all of them.
1246 if (bflags & BLIST_FORCELUN)
1247 max_dev_lun = shost->max_lun;
1249 * REGAL CDC-4X: avoid hang after LUN 4
1251 if (bflags & BLIST_MAX5LUN)
1252 max_dev_lun = min(5U, max_dev_lun);
1254 * Do not scan SCSI-2 or lower device past LUN 7, unless
1257 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1258 max_dev_lun = min(8U, max_dev_lun);
1261 * Stop scanning at 255 unless BLIST_SCSI3LUN
1263 if (!(bflags & BLIST_SCSI3LUN))
1264 max_dev_lun = min(256U, max_dev_lun);
1267 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1268 * until we reach the max, or no LUN is found and we are not
1271 for (lun = 1; lun < max_dev_lun; ++lun)
1272 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1273 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1279 * scsilun_to_int - convert a scsi_lun to an int
1280 * @scsilun: struct scsi_lun to be converted.
1283 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
1284 * integer, and return the result. The caller must check for
1285 * truncation before using this function.
1288 * For a description of the LUN format, post SCSI-3 see the SCSI
1289 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
1291 * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function
1292 * returns the integer: 0x0b03d204
1294 * This encoding will return a standard integer LUN for LUNs smaller
1295 * than 256, which typically use a single level LUN structure with
1296 * addressing method 0.
1298 u64 scsilun_to_int(struct scsi_lun *scsilun)
1304 for (i = 0; i < sizeof(lun); i += 2)
1305 lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) |
1306 ((u64)scsilun->scsi_lun[i + 1] << (i * 8)));
1309 EXPORT_SYMBOL(scsilun_to_int);
1312 * int_to_scsilun - reverts an int into a scsi_lun
1313 * @lun: integer to be reverted
1314 * @scsilun: struct scsi_lun to be set.
1317 * Reverts the functionality of the scsilun_to_int, which packed
1318 * an 8-byte lun value into an int. This routine unpacks the int
1319 * back into the lun value.
1322 * Given an integer : 0x0b03d204, this function returns a
1323 * struct scsi_lun of: d2 04 0b 03 00 00 00 00
1326 void int_to_scsilun(u64 lun, struct scsi_lun *scsilun)
1330 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
1332 for (i = 0; i < sizeof(lun); i += 2) {
1333 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
1334 scsilun->scsi_lun[i+1] = lun & 0xFF;
1338 EXPORT_SYMBOL(int_to_scsilun);
1341 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1342 * @starget: which target
1343 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1344 * @rescan: nonzero if we can skip code only needed on first scan
1347 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1348 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1350 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1351 * LUNs even if it's older than SCSI-3.
1352 * If BLIST_NOREPORTLUN is set, return 1 always.
1353 * If BLIST_NOLUN is set, return 0 always.
1354 * If starget->no_report_luns is set, return 1 always.
1357 * 0: scan completed (or no memory, so further scanning is futile)
1358 * 1: could not scan with REPORT LUN
1360 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1364 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1365 unsigned int length;
1367 unsigned int num_luns;
1368 unsigned int retries;
1370 struct scsi_lun *lunp, *lun_data;
1372 struct scsi_sense_hdr sshdr;
1373 struct scsi_device *sdev;
1374 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1378 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1379 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1380 * support more than 8 LUNs.
1381 * Don't attempt if the target doesn't support REPORT LUNS.
1383 if (bflags & BLIST_NOREPORTLUN)
1385 if (starget->scsi_level < SCSI_2 &&
1386 starget->scsi_level != SCSI_UNKNOWN)
1388 if (starget->scsi_level < SCSI_3 &&
1389 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1391 if (bflags & BLIST_NOLUN)
1393 if (starget->no_report_luns)
1396 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1397 sdev = scsi_alloc_sdev(starget, 0, NULL);
1400 if (scsi_device_get(sdev)) {
1401 __scsi_remove_device(sdev);
1406 sprintf(devname, "host %d channel %d id %d",
1407 shost->host_no, sdev->channel, sdev->id);
1410 * Allocate enough to hold the header (the same size as one scsi_lun)
1411 * plus the max number of luns we are requesting.
1413 * Reallocating and trying again (with the exact amount we need)
1414 * would be nice, but then we need to somehow limit the size
1415 * allocated based on the available memory and the limits of
1416 * kmalloc - we don't want a kmalloc() failure of a huge value to
1417 * prevent us from finding any LUNs on this target.
1419 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
1420 lun_data = kmalloc(length, GFP_ATOMIC |
1421 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1423 printk(ALLOC_FAILURE_MSG, __func__);
1427 scsi_cmd[0] = REPORT_LUNS;
1430 * bytes 1 - 5: reserved, set to zero.
1432 memset(&scsi_cmd[1], 0, 5);
1435 * bytes 6 - 9: length of the command.
1437 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
1438 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
1439 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
1440 scsi_cmd[9] = (unsigned char) length & 0xff;
1442 scsi_cmd[10] = 0; /* reserved */
1443 scsi_cmd[11] = 0; /* control */
1446 * We can get a UNIT ATTENTION, for example a power on/reset, so
1447 * retry a few times (like sd.c does for TEST UNIT READY).
1448 * Experience shows some combinations of adapter/devices get at
1449 * least two power on/resets.
1451 * Illegal requests (for devices that do not support REPORT LUNS)
1452 * should come through as a check condition, and will not generate
1455 for (retries = 0; retries < 3; retries++) {
1456 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1457 "scsi scan: Sending REPORT LUNS to (try %d)\n",
1460 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1461 lun_data, length, &sshdr,
1462 SCSI_TIMEOUT + 4 * HZ, 3, NULL);
1464 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1465 "scsi scan: REPORT LUNS"
1466 " %s (try %d) result 0x%x\n",
1467 result ? "failed" : "successful",
1471 else if (scsi_sense_valid(&sshdr)) {
1472 if (sshdr.sense_key != UNIT_ATTENTION)
1479 * The device probably does not support a REPORT LUN command
1486 * Get the length from the first four bytes of lun_data.
1488 data = (u8 *) lun_data->scsi_lun;
1489 length = ((data[0] << 24) | (data[1] << 16) |
1490 (data[2] << 8) | (data[3] << 0));
1492 num_luns = (length / sizeof(struct scsi_lun));
1493 if (num_luns > max_scsi_report_luns) {
1494 sdev_printk(KERN_WARNING, sdev,
1495 "Only %d (max_scsi_report_luns)"
1496 " of %d luns reported, try increasing"
1497 " max_scsi_report_luns.\n",
1498 max_scsi_report_luns, num_luns);
1499 num_luns = max_scsi_report_luns;
1502 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1503 "scsi scan: REPORT LUN scan\n"));
1506 * Scan the luns in lun_data. The entry at offset 0 is really
1507 * the header, so start at 1 and go up to and including num_luns.
1509 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1510 lun = scsilun_to_int(lunp);
1512 if (lun > sdev->host->max_lun) {
1513 sdev_printk(KERN_WARNING, sdev,
1514 "lun%llu has a LUN larger than"
1515 " allowed by the host adapter\n", lun);
1519 res = scsi_probe_and_add_lun(starget,
1520 lun, NULL, NULL, rescan, NULL);
1521 if (res == SCSI_SCAN_NO_RESPONSE) {
1523 * Got some results, but now none, abort.
1525 sdev_printk(KERN_ERR, sdev,
1526 "Unexpected response"
1527 " from lun %llu while scanning, scan"
1528 " aborted\n", (unsigned long long)lun);
1537 scsi_device_put(sdev);
1538 if (scsi_device_created(sdev))
1540 * the sdev we used didn't appear in the report luns scan
1542 __scsi_remove_device(sdev);
1546 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1547 uint id, u64 lun, void *hostdata)
1549 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1550 struct device *parent = &shost->shost_gendev;
1551 struct scsi_target *starget;
1553 if (strncmp(scsi_scan_type, "none", 4) == 0)
1554 return ERR_PTR(-ENODEV);
1556 starget = scsi_alloc_target(parent, channel, id);
1558 return ERR_PTR(-ENOMEM);
1559 scsi_autopm_get_target(starget);
1561 mutex_lock(&shost->scan_mutex);
1562 if (!shost->async_scan)
1563 scsi_complete_async_scans();
1565 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1566 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1567 scsi_autopm_put_host(shost);
1569 mutex_unlock(&shost->scan_mutex);
1570 scsi_autopm_put_target(starget);
1572 * paired with scsi_alloc_target(). Target will be destroyed unless
1573 * scsi_probe_and_add_lun made an underlying device visible
1575 scsi_target_reap(starget);
1576 put_device(&starget->dev);
1580 EXPORT_SYMBOL(__scsi_add_device);
1582 int scsi_add_device(struct Scsi_Host *host, uint channel,
1583 uint target, u64 lun)
1585 struct scsi_device *sdev =
1586 __scsi_add_device(host, channel, target, lun, NULL);
1588 return PTR_ERR(sdev);
1590 scsi_device_put(sdev);
1593 EXPORT_SYMBOL(scsi_add_device);
1595 void scsi_rescan_device(struct device *dev)
1600 if (try_module_get(dev->driver->owner)) {
1601 struct scsi_driver *drv = to_scsi_driver(dev->driver);
1605 module_put(dev->driver->owner);
1608 EXPORT_SYMBOL(scsi_rescan_device);
1610 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1611 unsigned int id, u64 lun, int rescan)
1613 struct Scsi_Host *shost = dev_to_shost(parent);
1616 struct scsi_target *starget;
1618 if (shost->this_id == id)
1620 * Don't scan the host adapter
1624 starget = scsi_alloc_target(parent, channel, id);
1627 scsi_autopm_get_target(starget);
1629 if (lun != SCAN_WILD_CARD) {
1631 * Scan for a specific host/chan/id/lun.
1633 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1638 * Scan LUN 0, if there is some response, scan further. Ideally, we
1639 * would not configure LUN 0 until all LUNs are scanned.
1641 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1642 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1643 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1645 * The REPORT LUN did not scan the target,
1646 * do a sequential scan.
1648 scsi_sequential_lun_scan(starget, bflags,
1649 starget->scsi_level, rescan);
1653 scsi_autopm_put_target(starget);
1655 * paired with scsi_alloc_target(): determine if the target has
1656 * any children at all and if not, nuke it
1658 scsi_target_reap(starget);
1660 put_device(&starget->dev);
1664 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1665 * @parent: host to scan
1666 * @channel: channel to scan
1667 * @id: target id to scan
1668 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1669 * @rescan: passed to LUN scanning routines
1672 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1673 * and possibly all LUNs on the target id.
1675 * First try a REPORT LUN scan, if that does not scan the target, do a
1676 * sequential scan of LUNs on the target id.
1678 void scsi_scan_target(struct device *parent, unsigned int channel,
1679 unsigned int id, u64 lun, int rescan)
1681 struct Scsi_Host *shost = dev_to_shost(parent);
1683 if (strncmp(scsi_scan_type, "none", 4) == 0)
1686 mutex_lock(&shost->scan_mutex);
1687 if (!shost->async_scan)
1688 scsi_complete_async_scans();
1690 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1691 __scsi_scan_target(parent, channel, id, lun, rescan);
1692 scsi_autopm_put_host(shost);
1694 mutex_unlock(&shost->scan_mutex);
1696 EXPORT_SYMBOL(scsi_scan_target);
1698 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1699 unsigned int id, u64 lun, int rescan)
1703 if (id == SCAN_WILD_CARD)
1704 for (id = 0; id < shost->max_id; ++id) {
1706 * XXX adapter drivers when possible (FCP, iSCSI)
1707 * could modify max_id to match the current max,
1708 * not the absolute max.
1710 * XXX add a shost id iterator, so for example,
1711 * the FC ID can be the same as a target id
1712 * without a huge overhead of sparse id's.
1714 if (shost->reverse_ordering)
1716 * Scan from high to low id.
1718 order_id = shost->max_id - id - 1;
1721 __scsi_scan_target(&shost->shost_gendev, channel,
1722 order_id, lun, rescan);
1725 __scsi_scan_target(&shost->shost_gendev, channel,
1729 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1730 unsigned int id, u64 lun, int rescan)
1732 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1733 "%s: <%u:%u:%llu>\n",
1734 __func__, channel, id, lun));
1736 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1737 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1738 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun)))
1741 mutex_lock(&shost->scan_mutex);
1742 if (!shost->async_scan)
1743 scsi_complete_async_scans();
1745 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1746 if (channel == SCAN_WILD_CARD)
1747 for (channel = 0; channel <= shost->max_channel;
1749 scsi_scan_channel(shost, channel, id, lun,
1752 scsi_scan_channel(shost, channel, id, lun, rescan);
1753 scsi_autopm_put_host(shost);
1755 mutex_unlock(&shost->scan_mutex);
1760 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1762 struct scsi_device *sdev;
1763 shost_for_each_device(sdev, shost) {
1764 /* target removed before the device could be added */
1765 if (sdev->sdev_state == SDEV_DEL)
1767 /* If device is already visible, skip adding it to sysfs */
1768 if (sdev->is_visible)
1770 if (!scsi_host_scan_allowed(shost) ||
1771 scsi_sysfs_add_sdev(sdev) != 0)
1772 __scsi_remove_device(sdev);
1777 * scsi_prep_async_scan - prepare for an async scan
1778 * @shost: the host which will be scanned
1779 * Returns: a cookie to be passed to scsi_finish_async_scan()
1781 * Tells the midlayer this host is going to do an asynchronous scan.
1782 * It reserves the host's position in the scanning list and ensures
1783 * that other asynchronous scans started after this one won't affect the
1784 * ordering of the discovered devices.
1786 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1788 struct async_scan_data *data;
1789 unsigned long flags;
1791 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1794 if (shost->async_scan) {
1795 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
1800 data = kmalloc(sizeof(*data), GFP_KERNEL);
1803 data->shost = scsi_host_get(shost);
1806 init_completion(&data->prev_finished);
1808 mutex_lock(&shost->scan_mutex);
1809 spin_lock_irqsave(shost->host_lock, flags);
1810 shost->async_scan = 1;
1811 spin_unlock_irqrestore(shost->host_lock, flags);
1812 mutex_unlock(&shost->scan_mutex);
1814 spin_lock(&async_scan_lock);
1815 if (list_empty(&scanning_hosts))
1816 complete(&data->prev_finished);
1817 list_add_tail(&data->list, &scanning_hosts);
1818 spin_unlock(&async_scan_lock);
1828 * scsi_finish_async_scan - asynchronous scan has finished
1829 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1831 * All the devices currently attached to this host have been found.
1832 * This function announces all the devices it has found to the rest
1835 static void scsi_finish_async_scan(struct async_scan_data *data)
1837 struct Scsi_Host *shost;
1838 unsigned long flags;
1843 shost = data->shost;
1845 mutex_lock(&shost->scan_mutex);
1847 if (!shost->async_scan) {
1848 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
1850 mutex_unlock(&shost->scan_mutex);
1854 wait_for_completion(&data->prev_finished);
1856 scsi_sysfs_add_devices(shost);
1858 spin_lock_irqsave(shost->host_lock, flags);
1859 shost->async_scan = 0;
1860 spin_unlock_irqrestore(shost->host_lock, flags);
1862 mutex_unlock(&shost->scan_mutex);
1864 spin_lock(&async_scan_lock);
1865 list_del(&data->list);
1866 if (!list_empty(&scanning_hosts)) {
1867 struct async_scan_data *next = list_entry(scanning_hosts.next,
1868 struct async_scan_data, list);
1869 complete(&next->prev_finished);
1871 spin_unlock(&async_scan_lock);
1873 scsi_autopm_put_host(shost);
1874 scsi_host_put(shost);
1878 static void do_scsi_scan_host(struct Scsi_Host *shost)
1880 if (shost->hostt->scan_finished) {
1881 unsigned long start = jiffies;
1882 if (shost->hostt->scan_start)
1883 shost->hostt->scan_start(shost);
1885 while (!shost->hostt->scan_finished(shost, jiffies - start))
1888 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1893 static void do_scan_async(void *_data, async_cookie_t c)
1895 struct async_scan_data *data = _data;
1896 struct Scsi_Host *shost = data->shost;
1898 do_scsi_scan_host(shost);
1899 scsi_finish_async_scan(data);
1903 * scsi_scan_host - scan the given adapter
1904 * @shost: adapter to scan
1906 void scsi_scan_host(struct Scsi_Host *shost)
1908 struct async_scan_data *data;
1910 if (strncmp(scsi_scan_type, "none", 4) == 0)
1912 if (scsi_autopm_get_host(shost) < 0)
1915 data = scsi_prep_async_scan(shost);
1917 do_scsi_scan_host(shost);
1918 scsi_autopm_put_host(shost);
1922 /* register with the async subsystem so wait_for_device_probe()
1923 * will flush this work
1925 async_schedule(do_scan_async, data);
1927 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
1929 EXPORT_SYMBOL(scsi_scan_host);
1931 void scsi_forget_host(struct Scsi_Host *shost)
1933 struct scsi_device *sdev;
1934 unsigned long flags;
1937 spin_lock_irqsave(shost->host_lock, flags);
1938 list_for_each_entry(sdev, &shost->__devices, siblings) {
1939 if (sdev->sdev_state == SDEV_DEL)
1941 spin_unlock_irqrestore(shost->host_lock, flags);
1942 __scsi_remove_device(sdev);
1945 spin_unlock_irqrestore(shost->host_lock, flags);
1949 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself
1950 * @shost: Host that needs a scsi_device
1952 * Lock status: None assumed.
1954 * Returns: The scsi_device or NULL
1957 * Attach a single scsi_device to the Scsi_Host - this should
1958 * be made to look like a "pseudo-device" that points to the
1961 * Note - this device is not accessible from any high-level
1962 * drivers (including generics), which is probably not
1963 * optimal. We can add hooks later to attach.
1965 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1967 struct scsi_device *sdev = NULL;
1968 struct scsi_target *starget;
1970 mutex_lock(&shost->scan_mutex);
1971 if (!scsi_host_scan_allowed(shost))
1973 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1977 sdev = scsi_alloc_sdev(starget, 0, NULL);
1981 scsi_target_reap(starget);
1982 put_device(&starget->dev);
1984 mutex_unlock(&shost->scan_mutex);
1987 EXPORT_SYMBOL(scsi_get_host_dev);
1990 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself
1991 * @sdev: Host device to be freed
1993 * Lock status: None assumed.
1997 void scsi_free_host_dev(struct scsi_device *sdev)
1999 BUG_ON(sdev->id != sdev->host->this_id);
2001 __scsi_remove_device(sdev);
2003 EXPORT_SYMBOL(scsi_free_host_dev);