1 // SPDX-License-Identifier: GPL-2.0
5 * Copyright (C) 2000 Eric Youngdale,
6 * Copyright (C) 2002 Patrick Mansfield
8 * The general scanning/probing algorithm is as follows, exceptions are
9 * made to it depending on device specific flags, compilation options, and
10 * global variable (boot or module load time) settings.
12 * A specific LUN is scanned via an INQUIRY command; if the LUN has a
13 * device attached, a scsi_device is allocated and setup for it.
15 * For every id of every channel on the given host:
17 * Scan LUN 0; if the target responds to LUN 0 (even if there is no
18 * device or storage attached to LUN 0):
20 * If LUN 0 has a device attached, allocate and setup a
23 * If target is SCSI-3 or up, issue a REPORT LUN, and scan
24 * all of the LUNs returned by the REPORT LUN; else,
25 * sequentially scan LUNs up until some maximum is reached,
26 * or a LUN is seen that cannot have a device attached to it.
29 #include <linux/module.h>
30 #include <linux/moduleparam.h>
31 #include <linux/init.h>
32 #include <linux/blkdev.h>
33 #include <linux/delay.h>
34 #include <linux/kthread.h>
35 #include <linux/spinlock.h>
36 #include <linux/async.h>
37 #include <linux/slab.h>
38 #include <asm/unaligned.h>
40 #include <scsi/scsi.h>
41 #include <scsi/scsi_cmnd.h>
42 #include <scsi/scsi_device.h>
43 #include <scsi/scsi_driver.h>
44 #include <scsi/scsi_devinfo.h>
45 #include <scsi/scsi_host.h>
46 #include <scsi/scsi_transport.h>
47 #include <scsi/scsi_dh.h>
48 #include <scsi/scsi_eh.h>
50 #include "scsi_priv.h"
51 #include "scsi_logging.h"
53 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
54 " SCSI scanning, some SCSI devices might not be configured\n"
59 #define SCSI_TIMEOUT (2*HZ)
60 #define SCSI_REPORT_LUNS_TIMEOUT (30*HZ)
63 * Prefix values for the SCSI id's (stored in sysfs name field)
65 #define SCSI_UID_SER_NUM 'S'
66 #define SCSI_UID_UNKNOWN 'Z'
69 * Return values of some of the scanning functions.
71 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
72 * includes allocation or general failures preventing IO from being sent.
74 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
77 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
80 #define SCSI_SCAN_NO_RESPONSE 0
81 #define SCSI_SCAN_TARGET_PRESENT 1
82 #define SCSI_SCAN_LUN_PRESENT 2
84 static const char *scsi_null_device_strs = "nullnullnullnull";
86 #define MAX_SCSI_LUNS 512
88 static u64 max_scsi_luns = MAX_SCSI_LUNS;
90 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR);
91 MODULE_PARM_DESC(max_luns,
92 "last scsi LUN (should be between 1 and 2^64-1)");
94 #ifdef CONFIG_SCSI_SCAN_ASYNC
95 #define SCSI_SCAN_TYPE_DEFAULT "async"
97 #define SCSI_SCAN_TYPE_DEFAULT "sync"
100 static char scsi_scan_type[7] = SCSI_SCAN_TYPE_DEFAULT;
102 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type),
104 MODULE_PARM_DESC(scan, "sync, async, manual, or none. "
105 "Setting to 'manual' disables automatic scanning, but allows "
106 "for manual device scan via the 'scan' sysfs attribute.");
108 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
110 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
111 MODULE_PARM_DESC(inq_timeout,
112 "Timeout (in seconds) waiting for devices to answer INQUIRY."
113 " Default is 20. Some devices may need more; most need less.");
115 /* This lock protects only this list */
116 static DEFINE_SPINLOCK(async_scan_lock);
117 static LIST_HEAD(scanning_hosts);
119 struct async_scan_data {
120 struct list_head list;
121 struct Scsi_Host *shost;
122 struct completion prev_finished;
126 * scsi_enable_async_suspend - Enable async suspend and resume
128 void scsi_enable_async_suspend(struct device *dev)
131 * If a user has disabled async probing a likely reason is due to a
132 * storage enclosure that does not inject staggered spin-ups. For
133 * safety, make resume synchronous as well in that case.
135 if (strncmp(scsi_scan_type, "async", 5) != 0)
137 /* Enable asynchronous suspend and resume. */
138 device_enable_async_suspend(dev);
142 * scsi_complete_async_scans - Wait for asynchronous scans to complete
144 * When this function returns, any host which started scanning before
145 * this function was called will have finished its scan. Hosts which
146 * started scanning after this function was called may or may not have
149 int scsi_complete_async_scans(void)
151 struct async_scan_data *data;
154 if (list_empty(&scanning_hosts))
156 /* If we can't get memory immediately, that's OK. Just
157 * sleep a little. Even if we never get memory, the async
158 * scans will finish eventually.
160 data = kmalloc(sizeof(*data), GFP_KERNEL);
166 init_completion(&data->prev_finished);
168 spin_lock(&async_scan_lock);
169 /* Check that there's still somebody else on the list */
170 if (list_empty(&scanning_hosts))
172 list_add_tail(&data->list, &scanning_hosts);
173 spin_unlock(&async_scan_lock);
175 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
176 wait_for_completion(&data->prev_finished);
178 spin_lock(&async_scan_lock);
179 list_del(&data->list);
180 if (!list_empty(&scanning_hosts)) {
181 struct async_scan_data *next = list_entry(scanning_hosts.next,
182 struct async_scan_data, list);
183 complete(&next->prev_finished);
186 spin_unlock(&async_scan_lock);
193 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
194 * @sdev: scsi device to send command to
195 * @result: area to store the result of the MODE SENSE
198 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
199 * Called for BLIST_KEY devices.
201 static void scsi_unlock_floptical(struct scsi_device *sdev,
202 unsigned char *result)
204 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
206 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n");
207 scsi_cmd[0] = MODE_SENSE;
211 scsi_cmd[4] = 0x2a; /* size */
213 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
214 SCSI_TIMEOUT, 3, NULL);
217 static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev,
220 int new_shift = sbitmap_calculate_shift(depth);
221 bool need_alloc = !sdev->budget_map.map;
222 bool need_free = false;
224 struct sbitmap sb_backup;
226 depth = min_t(unsigned int, depth, scsi_device_max_queue_depth(sdev));
229 * realloc if new shift is calculated, which is caused by setting
230 * up one new default queue depth after calling ->slave_configure
232 if (!need_alloc && new_shift != sdev->budget_map.shift)
233 need_alloc = need_free = true;
239 * Request queue has to be frozen for reallocating budget map,
240 * and here disk isn't added yet, so freezing is pretty fast
243 blk_mq_freeze_queue(sdev->request_queue);
244 sb_backup = sdev->budget_map;
246 ret = sbitmap_init_node(&sdev->budget_map,
247 scsi_device_max_queue_depth(sdev),
248 new_shift, GFP_KERNEL,
249 sdev->request_queue->node, false, true);
251 sbitmap_resize(&sdev->budget_map, depth);
255 sdev->budget_map = sb_backup;
257 sbitmap_free(&sb_backup);
259 blk_mq_unfreeze_queue(sdev->request_queue);
265 * scsi_alloc_sdev - allocate and setup a scsi_Device
266 * @starget: which target to allocate a &scsi_device for
268 * @hostdata: usually NULL and set by ->slave_alloc instead
271 * Allocate, initialize for io, and return a pointer to a scsi_Device.
272 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
273 * adds scsi_Device to the appropriate list.
276 * scsi_Device pointer, or NULL on failure.
278 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
279 u64 lun, void *hostdata)
282 struct scsi_device *sdev;
283 struct request_queue *q;
284 int display_failure_msg = 1, ret;
285 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
287 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
292 sdev->vendor = scsi_null_device_strs;
293 sdev->model = scsi_null_device_strs;
294 sdev->rev = scsi_null_device_strs;
296 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
297 sdev->id = starget->id;
299 sdev->channel = starget->channel;
300 mutex_init(&sdev->state_mutex);
301 sdev->sdev_state = SDEV_CREATED;
302 INIT_LIST_HEAD(&sdev->siblings);
303 INIT_LIST_HEAD(&sdev->same_target_siblings);
304 INIT_LIST_HEAD(&sdev->starved_entry);
305 INIT_LIST_HEAD(&sdev->event_list);
306 spin_lock_init(&sdev->list_lock);
307 mutex_init(&sdev->inquiry_mutex);
308 INIT_WORK(&sdev->event_work, scsi_evt_thread);
309 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
311 sdev->sdev_gendev.parent = get_device(&starget->dev);
312 sdev->sdev_target = starget;
314 /* usually NULL and set by ->slave_alloc instead */
315 sdev->hostdata = hostdata;
317 /* if the device needs this changing, it may do so in the
318 * slave_configure function */
319 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
322 * Some low level driver could use device->type
327 * Assume that the device will have handshaking problems,
328 * and then fix this field later if it turns out it
333 sdev->sg_reserved_size = INT_MAX;
335 q = blk_mq_init_queue(&sdev->host->tag_set);
337 /* release fn is set up in scsi_sysfs_device_initialise, so
338 * have to free and put manually here */
339 put_device(&starget->dev);
343 sdev->request_queue = q;
345 __scsi_init_queue(sdev->host, q);
346 WARN_ON_ONCE(!blk_get_queue(q));
348 depth = sdev->host->cmd_per_lun ?: 1;
351 * Use .can_queue as budget map's depth because we have to
352 * support adjusting queue depth from sysfs. Meantime use
353 * default device queue depth to figure out sbitmap shift
354 * since we use this queue depth most of times.
356 if (scsi_realloc_sdev_budget_map(sdev, depth)) {
357 put_device(&starget->dev);
362 scsi_change_queue_depth(sdev, depth);
364 scsi_sysfs_device_initialize(sdev);
366 if (shost->hostt->slave_alloc) {
367 ret = shost->hostt->slave_alloc(sdev);
370 * if LLDD reports slave not present, don't clutter
371 * console with alloc failure messages
374 display_failure_msg = 0;
375 goto out_device_destroy;
382 __scsi_remove_device(sdev);
384 if (display_failure_msg)
385 printk(ALLOC_FAILURE_MSG, __func__);
389 static void scsi_target_destroy(struct scsi_target *starget)
391 struct device *dev = &starget->dev;
392 struct Scsi_Host *shost = dev_to_shost(dev->parent);
395 BUG_ON(starget->state == STARGET_DEL);
396 starget->state = STARGET_DEL;
397 transport_destroy_device(dev);
398 spin_lock_irqsave(shost->host_lock, flags);
399 if (shost->hostt->target_destroy)
400 shost->hostt->target_destroy(starget);
401 list_del_init(&starget->siblings);
402 spin_unlock_irqrestore(shost->host_lock, flags);
406 static void scsi_target_dev_release(struct device *dev)
408 struct device *parent = dev->parent;
409 struct scsi_target *starget = to_scsi_target(dev);
415 static struct device_type scsi_target_type = {
416 .name = "scsi_target",
417 .release = scsi_target_dev_release,
420 int scsi_is_target_device(const struct device *dev)
422 return dev->type == &scsi_target_type;
424 EXPORT_SYMBOL(scsi_is_target_device);
426 static struct scsi_target *__scsi_find_target(struct device *parent,
427 int channel, uint id)
429 struct scsi_target *starget, *found_starget = NULL;
430 struct Scsi_Host *shost = dev_to_shost(parent);
432 * Search for an existing target for this sdev.
434 list_for_each_entry(starget, &shost->__targets, siblings) {
435 if (starget->id == id &&
436 starget->channel == channel) {
437 found_starget = starget;
442 get_device(&found_starget->dev);
444 return found_starget;
448 * scsi_target_reap_ref_release - remove target from visibility
449 * @kref: the reap_ref in the target being released
451 * Called on last put of reap_ref, which is the indication that no device
452 * under this target is visible anymore, so render the target invisible in
453 * sysfs. Note: we have to be in user context here because the target reaps
454 * should be done in places where the scsi device visibility is being removed.
456 static void scsi_target_reap_ref_release(struct kref *kref)
458 struct scsi_target *starget
459 = container_of(kref, struct scsi_target, reap_ref);
462 * if we get here and the target is still in a CREATED state that
463 * means it was allocated but never made visible (because a scan
464 * turned up no LUNs), so don't call device_del() on it.
466 if ((starget->state != STARGET_CREATED) &&
467 (starget->state != STARGET_CREATED_REMOVE)) {
468 transport_remove_device(&starget->dev);
469 device_del(&starget->dev);
471 scsi_target_destroy(starget);
474 static void scsi_target_reap_ref_put(struct scsi_target *starget)
476 kref_put(&starget->reap_ref, scsi_target_reap_ref_release);
480 * scsi_alloc_target - allocate a new or find an existing target
481 * @parent: parent of the target (need not be a scsi host)
482 * @channel: target channel number (zero if no channels)
483 * @id: target id number
485 * Return an existing target if one exists, provided it hasn't already
486 * gone into STARGET_DEL state, otherwise allocate a new target.
488 * The target is returned with an incremented reference, so the caller
489 * is responsible for both reaping and doing a last put
491 static struct scsi_target *scsi_alloc_target(struct device *parent,
492 int channel, uint id)
494 struct Scsi_Host *shost = dev_to_shost(parent);
495 struct device *dev = NULL;
497 const int size = sizeof(struct scsi_target)
498 + shost->transportt->target_size;
499 struct scsi_target *starget;
500 struct scsi_target *found_target;
503 starget = kzalloc(size, GFP_KERNEL);
505 printk(KERN_ERR "%s: allocation failure\n", __func__);
509 device_initialize(dev);
510 kref_init(&starget->reap_ref);
511 dev->parent = get_device(parent);
512 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
513 dev->bus = &scsi_bus_type;
514 dev->type = &scsi_target_type;
515 scsi_enable_async_suspend(dev);
517 starget->channel = channel;
518 starget->can_queue = 0;
519 INIT_LIST_HEAD(&starget->siblings);
520 INIT_LIST_HEAD(&starget->devices);
521 starget->state = STARGET_CREATED;
522 starget->scsi_level = SCSI_2;
523 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
525 spin_lock_irqsave(shost->host_lock, flags);
527 found_target = __scsi_find_target(parent, channel, id);
531 list_add_tail(&starget->siblings, &shost->__targets);
532 spin_unlock_irqrestore(shost->host_lock, flags);
533 /* allocate and add */
534 transport_setup_device(dev);
535 if (shost->hostt->target_alloc) {
536 error = shost->hostt->target_alloc(starget);
540 dev_err(dev, "target allocation failed, error %d\n", error);
541 /* don't want scsi_target_reap to do the final
542 * put because it will be under the host lock */
543 scsi_target_destroy(starget);
553 * release routine already fired if kref is zero, so if we can still
554 * take the reference, the target must be alive. If we can't, it must
555 * be dying and we need to wait for a new target
557 ref_got = kref_get_unless_zero(&found_target->reap_ref);
559 spin_unlock_irqrestore(shost->host_lock, flags);
565 * Unfortunately, we found a dying target; need to wait until it's
566 * dead before we can get a new one. There is an anomaly here. We
567 * *should* call scsi_target_reap() to balance the kref_get() of the
568 * reap_ref above. However, since the target being released, it's
569 * already invisible and the reap_ref is irrelevant. If we call
570 * scsi_target_reap() we might spuriously do another device_del() on
571 * an already invisible target.
573 put_device(&found_target->dev);
575 * length of time is irrelevant here, we just want to yield the CPU
576 * for a tick to avoid busy waiting for the target to die.
583 * scsi_target_reap - check to see if target is in use and destroy if not
584 * @starget: target to be checked
586 * This is used after removing a LUN or doing a last put of the target
587 * it checks atomically that nothing is using the target and removes
590 void scsi_target_reap(struct scsi_target *starget)
593 * serious problem if this triggers: STARGET_DEL is only set in the if
594 * the reap_ref drops to zero, so we're trying to do another final put
595 * on an already released kref
597 BUG_ON(starget->state == STARGET_DEL);
598 scsi_target_reap_ref_put(starget);
602 * scsi_sanitize_inquiry_string - remove non-graphical chars from an
603 * INQUIRY result string
604 * @s: INQUIRY result string to sanitize
605 * @len: length of the string
608 * The SCSI spec says that INQUIRY vendor, product, and revision
609 * strings must consist entirely of graphic ASCII characters,
610 * padded on the right with spaces. Since not all devices obey
611 * this rule, we will replace non-graphic or non-ASCII characters
612 * with spaces. Exception: a NUL character is interpreted as a
613 * string terminator, so all the following characters are set to
616 void scsi_sanitize_inquiry_string(unsigned char *s, int len)
620 for (; len > 0; (--len, ++s)) {
623 if (terminated || *s < 0x20 || *s > 0x7e)
627 EXPORT_SYMBOL(scsi_sanitize_inquiry_string);
630 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
631 * @sdev: scsi_device to probe
632 * @inq_result: area to store the INQUIRY result
633 * @result_len: len of inq_result
634 * @bflags: store any bflags found here
637 * Probe the lun associated with @req using a standard SCSI INQUIRY;
639 * If the INQUIRY is successful, zero is returned and the
640 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
641 * are copied to the scsi_device any flags value is stored in *@bflags.
643 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
644 int result_len, blist_flags_t *bflags)
646 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
647 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
648 int response_len = 0;
649 int pass, count, result;
650 struct scsi_sense_hdr sshdr;
654 /* Perform up to 3 passes. The first pass uses a conservative
655 * transfer length of 36 unless sdev->inquiry_len specifies a
656 * different value. */
657 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
658 try_inquiry_len = first_inquiry_len;
662 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
663 "scsi scan: INQUIRY pass %d length %d\n",
664 pass, try_inquiry_len));
666 /* Each pass gets up to three chances to ignore Unit Attention */
667 for (count = 0; count < 3; ++count) {
670 memset(scsi_cmd, 0, 6);
671 scsi_cmd[0] = INQUIRY;
672 scsi_cmd[4] = (unsigned char) try_inquiry_len;
674 memset(inq_result, 0, try_inquiry_len);
676 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
677 inq_result, try_inquiry_len, &sshdr,
678 HZ / 2 + HZ * scsi_inq_timeout, 3,
681 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
682 "scsi scan: INQUIRY %s with code 0x%x\n",
683 result ? "failed" : "successful", result));
687 * not-ready to ready transition [asc/ascq=0x28/0x0]
688 * or power-on, reset [asc/ascq=0x29/0x0], continue.
689 * INQUIRY should not yield UNIT_ATTENTION
690 * but many buggy devices do so anyway.
692 if (scsi_status_is_check_condition(result) &&
693 scsi_sense_valid(&sshdr)) {
694 if ((sshdr.sense_key == UNIT_ATTENTION) &&
695 ((sshdr.asc == 0x28) ||
696 (sshdr.asc == 0x29)) &&
700 } else if (result == 0) {
702 * if nothing was transferred, we try
703 * again. It's a workaround for some USB
706 if (resid == try_inquiry_len)
713 scsi_sanitize_inquiry_string(&inq_result[8], 8);
714 scsi_sanitize_inquiry_string(&inq_result[16], 16);
715 scsi_sanitize_inquiry_string(&inq_result[32], 4);
717 response_len = inq_result[4] + 5;
718 if (response_len > 255)
719 response_len = first_inquiry_len; /* sanity */
722 * Get any flags for this device.
724 * XXX add a bflags to scsi_device, and replace the
725 * corresponding bit fields in scsi_device, so bflags
726 * need not be passed as an argument.
728 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
731 /* When the first pass succeeds we gain information about
732 * what larger transfer lengths might work. */
734 if (BLIST_INQUIRY_36 & *bflags)
735 next_inquiry_len = 36;
736 else if (sdev->inquiry_len)
737 next_inquiry_len = sdev->inquiry_len;
739 next_inquiry_len = response_len;
741 /* If more data is available perform the second pass */
742 if (next_inquiry_len > try_inquiry_len) {
743 try_inquiry_len = next_inquiry_len;
749 } else if (pass == 2) {
750 sdev_printk(KERN_INFO, sdev,
751 "scsi scan: %d byte inquiry failed. "
752 "Consider BLIST_INQUIRY_36 for this device\n",
755 /* If this pass failed, the third pass goes back and transfers
756 * the same amount as we successfully got in the first pass. */
757 try_inquiry_len = first_inquiry_len;
762 /* If the last transfer attempt got an error, assume the
763 * peripheral doesn't exist or is dead. */
767 /* Don't report any more data than the device says is valid */
768 sdev->inquiry_len = min(try_inquiry_len, response_len);
771 * XXX Abort if the response length is less than 36? If less than
772 * 32, the lookup of the device flags (above) could be invalid,
773 * and it would be possible to take an incorrect action - we do
774 * not want to hang because of a short INQUIRY. On the flip side,
775 * if the device is spun down or becoming ready (and so it gives a
776 * short INQUIRY), an abort here prevents any further use of the
777 * device, including spin up.
779 * On the whole, the best approach seems to be to assume the first
780 * 36 bytes are valid no matter what the device says. That's
781 * better than copying < 36 bytes to the inquiry-result buffer
782 * and displaying garbage for the Vendor, Product, or Revision
785 if (sdev->inquiry_len < 36) {
786 if (!sdev->host->short_inquiry) {
787 shost_printk(KERN_INFO, sdev->host,
788 "scsi scan: INQUIRY result too short (%d),"
789 " using 36\n", sdev->inquiry_len);
790 sdev->host->short_inquiry = 1;
792 sdev->inquiry_len = 36;
796 * Related to the above issue:
798 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
799 * and if not ready, sent a START_STOP to start (maybe spin up) and
800 * then send the INQUIRY again, since the INQUIRY can change after
801 * a device is initialized.
803 * Ideally, start a device if explicitly asked to do so. This
804 * assumes that a device is spun up on power on, spun down on
805 * request, and then spun up on request.
809 * The scanning code needs to know the scsi_level, even if no
810 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
811 * non-zero LUNs can be scanned.
813 sdev->scsi_level = inq_result[2] & 0x07;
814 if (sdev->scsi_level >= 2 ||
815 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
817 sdev->sdev_target->scsi_level = sdev->scsi_level;
820 * If SCSI-2 or lower, and if the transport requires it,
821 * store the LUN value in CDB[1].
823 sdev->lun_in_cdb = 0;
824 if (sdev->scsi_level <= SCSI_2 &&
825 sdev->scsi_level != SCSI_UNKNOWN &&
826 !sdev->host->no_scsi2_lun_in_cdb)
827 sdev->lun_in_cdb = 1;
833 * scsi_add_lun - allocate and fully initialze a scsi_device
834 * @sdev: holds information to be stored in the new scsi_device
835 * @inq_result: holds the result of a previous INQUIRY to the LUN
836 * @bflags: black/white list flag
837 * @async: 1 if this device is being scanned asynchronously
840 * Initialize the scsi_device @sdev. Optionally set fields based
841 * on values in *@bflags.
844 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
845 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
847 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
848 blist_flags_t *bflags, int async)
853 * XXX do not save the inquiry, since it can change underneath us,
854 * save just vendor/model/rev.
856 * Rather than save it and have an ioctl that retrieves the saved
857 * value, have an ioctl that executes the same INQUIRY code used
858 * in scsi_probe_lun, let user level programs doing INQUIRY
859 * scanning run at their own risk, or supply a user level program
860 * that can correctly scan.
864 * Copy at least 36 bytes of INQUIRY data, so that we don't
865 * dereference unallocated memory when accessing the Vendor,
866 * Product, and Revision strings. Badly behaved devices may set
867 * the INQUIRY Additional Length byte to a small value, indicating
868 * these strings are invalid, but often they contain plausible data
869 * nonetheless. It doesn't matter if the device sent < 36 bytes
870 * total, since scsi_probe_lun() initializes inq_result with 0s.
872 sdev->inquiry = kmemdup(inq_result,
873 max_t(size_t, sdev->inquiry_len, 36),
875 if (sdev->inquiry == NULL)
876 return SCSI_SCAN_NO_RESPONSE;
878 sdev->vendor = (char *) (sdev->inquiry + 8);
879 sdev->model = (char *) (sdev->inquiry + 16);
880 sdev->rev = (char *) (sdev->inquiry + 32);
882 if (strncmp(sdev->vendor, "ATA ", 8) == 0) {
884 * sata emulation layer device. This is a hack to work around
885 * the SATL power management specifications which state that
886 * when the SATL detects the device has gone into standby
887 * mode, it shall respond with NOT READY.
889 sdev->allow_restart = 1;
892 if (*bflags & BLIST_ISROM) {
893 sdev->type = TYPE_ROM;
896 sdev->type = (inq_result[0] & 0x1f);
897 sdev->removable = (inq_result[1] & 0x80) >> 7;
900 * some devices may respond with wrong type for
901 * well-known logical units. Force well-known type
902 * to enumerate them correctly.
904 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) {
905 sdev_printk(KERN_WARNING, sdev,
906 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n",
907 __func__, sdev->type, (unsigned int)sdev->lun);
908 sdev->type = TYPE_WLUN;
913 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
914 /* RBC and MMC devices can return SCSI-3 compliance and yet
915 * still not support REPORT LUNS, so make them act as
916 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
917 * specifically set */
918 if ((*bflags & BLIST_REPORTLUN2) == 0)
919 *bflags |= BLIST_NOREPORTLUN;
923 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
924 * spec says: The device server is capable of supporting the
925 * specified peripheral device type on this logical unit. However,
926 * the physical device is not currently connected to this logical
929 * The above is vague, as it implies that we could treat 001 and
930 * 011 the same. Stay compatible with previous code, and create a
931 * scsi_device for a PQ of 1
933 * Don't set the device offline here; rather let the upper
934 * level drivers eval the PQ to decide whether they should
935 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
938 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
939 sdev->lockable = sdev->removable;
940 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
942 if (sdev->scsi_level >= SCSI_3 ||
943 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
945 if (inq_result[7] & 0x60)
947 if (inq_result[7] & 0x10)
950 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
951 "ANSI: %d%s\n", scsi_device_type(sdev->type),
952 sdev->vendor, sdev->model, sdev->rev,
953 sdev->inq_periph_qual, inq_result[2] & 0x07,
954 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
956 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
957 !(*bflags & BLIST_NOTQ)) {
958 sdev->tagged_supported = 1;
959 sdev->simple_tags = 1;
963 * Some devices (Texel CD ROM drives) have handshaking problems
964 * when used with the Seagate controllers. borken is initialized
965 * to 1, and then set it to 0 here.
967 if ((*bflags & BLIST_BORKEN) == 0)
970 if (*bflags & BLIST_NO_ULD_ATTACH)
971 sdev->no_uld_attach = 1;
974 * Apparently some really broken devices (contrary to the SCSI
975 * standards) need to be selected without asserting ATN
977 if (*bflags & BLIST_SELECT_NO_ATN)
978 sdev->select_no_atn = 1;
981 * Maximum 512 sector transfer length
982 * broken RA4x00 Compaq Disk Array
984 if (*bflags & BLIST_MAX_512)
985 blk_queue_max_hw_sectors(sdev->request_queue, 512);
987 * Max 1024 sector transfer length for targets that report incorrect
988 * max/optimal lengths and relied on the old block layer safe default
990 else if (*bflags & BLIST_MAX_1024)
991 blk_queue_max_hw_sectors(sdev->request_queue, 1024);
994 * Some devices may not want to have a start command automatically
995 * issued when a device is added.
997 if (*bflags & BLIST_NOSTARTONADD)
998 sdev->no_start_on_add = 1;
1000 if (*bflags & BLIST_SINGLELUN)
1001 scsi_target(sdev)->single_lun = 1;
1003 sdev->use_10_for_rw = 1;
1005 /* some devices don't like REPORT SUPPORTED OPERATION CODES
1006 * and will simply timeout causing sd_mod init to take a very
1008 if (*bflags & BLIST_NO_RSOC)
1009 sdev->no_report_opcodes = 1;
1011 /* set the device running here so that slave configure
1013 mutex_lock(&sdev->state_mutex);
1014 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
1016 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
1017 mutex_unlock(&sdev->state_mutex);
1020 sdev_printk(KERN_ERR, sdev,
1021 "in wrong state %s to complete scan\n",
1022 scsi_device_state_name(sdev->sdev_state));
1023 return SCSI_SCAN_NO_RESPONSE;
1026 if (*bflags & BLIST_NOT_LOCKABLE)
1029 if (*bflags & BLIST_RETRY_HWERROR)
1030 sdev->retry_hwerror = 1;
1032 if (*bflags & BLIST_NO_DIF)
1035 if (*bflags & BLIST_UNMAP_LIMIT_WS)
1036 sdev->unmap_limit_for_ws = 1;
1038 if (*bflags & BLIST_IGN_MEDIA_CHANGE)
1039 sdev->ignore_media_change = 1;
1041 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
1043 if (*bflags & BLIST_TRY_VPD_PAGES)
1044 sdev->try_vpd_pages = 1;
1045 else if (*bflags & BLIST_SKIP_VPD_PAGES)
1046 sdev->skip_vpd_pages = 1;
1048 transport_configure_device(&sdev->sdev_gendev);
1050 if (sdev->host->hostt->slave_configure) {
1051 ret = sdev->host->hostt->slave_configure(sdev);
1054 * if LLDD reports slave not present, don't clutter
1055 * console with alloc failure messages
1057 if (ret != -ENXIO) {
1058 sdev_printk(KERN_ERR, sdev,
1059 "failed to configure device\n");
1061 return SCSI_SCAN_NO_RESPONSE;
1065 * The queue_depth is often changed in ->slave_configure.
1066 * Set up budget map again since memory consumption of
1067 * the map depends on actual queue depth.
1069 scsi_realloc_sdev_budget_map(sdev, sdev->queue_depth);
1072 if (sdev->scsi_level >= SCSI_3)
1073 scsi_attach_vpd(sdev);
1075 sdev->max_queue_depth = sdev->queue_depth;
1076 WARN_ON_ONCE(sdev->max_queue_depth > sdev->budget_map.depth);
1077 sdev->sdev_bflags = *bflags;
1080 * Ok, the device is now all set up, we can
1081 * register it and tell the rest of the kernel
1084 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
1085 return SCSI_SCAN_NO_RESPONSE;
1087 return SCSI_SCAN_LUN_PRESENT;
1090 #ifdef CONFIG_SCSI_LOGGING
1092 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
1093 * @buf: Output buffer with at least end-first+1 bytes of space
1094 * @inq: Inquiry buffer (input)
1095 * @first: Offset of string into inq
1096 * @end: Index after last character in inq
1098 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
1099 unsigned first, unsigned end)
1101 unsigned term = 0, idx;
1103 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
1104 if (inq[idx+first] > ' ') {
1105 buf[idx] = inq[idx+first];
1117 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
1118 * @starget: pointer to target device structure
1119 * @lun: LUN of target device
1120 * @bflagsp: store bflags here if not NULL
1121 * @sdevp: probe the LUN corresponding to this scsi_device
1122 * @rescan: if not equal to SCSI_SCAN_INITIAL skip some code only
1123 * needed on first scan
1124 * @hostdata: passed to scsi_alloc_sdev()
1127 * Call scsi_probe_lun, if a LUN with an attached device is found,
1128 * allocate and set it up by calling scsi_add_lun.
1132 * - SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1133 * - SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1134 * attached at the LUN
1135 * - SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1137 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1138 u64 lun, blist_flags_t *bflagsp,
1139 struct scsi_device **sdevp,
1140 enum scsi_scan_mode rescan,
1143 struct scsi_device *sdev;
1144 unsigned char *result;
1145 blist_flags_t bflags;
1146 int res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1147 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1150 * The rescan flag is used as an optimization, the first scan of a
1151 * host adapter calls into here with rescan == 0.
1153 sdev = scsi_device_lookup_by_target(starget, lun);
1155 if (rescan != SCSI_SCAN_INITIAL || !scsi_device_created(sdev)) {
1156 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1157 "scsi scan: device exists on %s\n",
1158 dev_name(&sdev->sdev_gendev)));
1162 scsi_device_put(sdev);
1165 *bflagsp = scsi_get_device_flags(sdev,
1168 return SCSI_SCAN_LUN_PRESENT;
1170 scsi_device_put(sdev);
1172 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1176 result = kmalloc(result_len, GFP_KERNEL);
1180 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1181 goto out_free_result;
1186 * result contains valid SCSI INQUIRY data.
1188 if ((result[0] >> 5) == 3) {
1190 * For a Peripheral qualifier 3 (011b), the SCSI
1191 * spec says: The device server is not capable of
1192 * supporting a physical device on this logical
1195 * For disks, this implies that there is no
1196 * logical disk configured at sdev->lun, but there
1197 * is a target id responding.
1199 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1200 " peripheral qualifier of 3, device not"
1203 SCSI_LOG_SCAN_BUS(1, {
1204 unsigned char vend[9];
1205 unsigned char mod[17];
1207 sdev_printk(KERN_INFO, sdev,
1208 "scsi scan: consider passing scsi_mod."
1209 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1210 scsi_inq_str(vend, result, 8, 16),
1211 scsi_inq_str(mod, result, 16, 32));
1216 res = SCSI_SCAN_TARGET_PRESENT;
1217 goto out_free_result;
1221 * Some targets may set slight variations of PQ and PDT to signal
1222 * that no LUN is present, so don't add sdev in these cases.
1223 * Two specific examples are:
1224 * 1) NetApp targets: return PQ=1, PDT=0x1f
1225 * 2) IBM/2145 targets: return PQ=1, PDT=0
1226 * 3) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1227 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1230 * 1) SCSI SPC-3, pp. 145-146
1231 * PQ=1: "A peripheral device having the specified peripheral
1232 * device type is not connected to this logical unit. However, the
1233 * device server is capable of supporting the specified peripheral
1234 * device type on this logical unit."
1235 * PDT=0x1f: "Unknown or no device type"
1236 * 2) USB UFI 1.0, p. 20
1237 * PDT=00h Direct-access device (floppy)
1238 * PDT=1Fh none (no FDD connected to the requested logical unit)
1240 if (((result[0] >> 5) == 1 ||
1241 (starget->pdt_1f_for_no_lun && (result[0] & 0x1f) == 0x1f)) &&
1242 !scsi_is_wlun(lun)) {
1243 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1244 "scsi scan: peripheral device type"
1245 " of 31, no device added\n"));
1246 res = SCSI_SCAN_TARGET_PRESENT;
1247 goto out_free_result;
1250 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1251 if (res == SCSI_SCAN_LUN_PRESENT) {
1252 if (bflags & BLIST_KEY) {
1254 scsi_unlock_floptical(sdev, result);
1261 if (res == SCSI_SCAN_LUN_PRESENT) {
1263 if (scsi_device_get(sdev) == 0) {
1266 __scsi_remove_device(sdev);
1267 res = SCSI_SCAN_NO_RESPONSE;
1271 __scsi_remove_device(sdev);
1277 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1278 * @starget: pointer to target structure to scan
1279 * @bflags: black/white list flag for LUN 0
1280 * @scsi_level: Which version of the standard does this device adhere to
1281 * @rescan: passed to scsi_probe_add_lun()
1284 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1285 * scanned) to some maximum lun until a LUN is found with no device
1286 * attached. Use the bflags to figure out any oddities.
1288 * Modifies sdevscan->lun.
1290 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1291 blist_flags_t bflags, int scsi_level,
1292 enum scsi_scan_mode rescan)
1295 u64 sparse_lun, lun;
1296 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1298 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget,
1299 "scsi scan: Sequential scan\n"));
1301 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1303 * If this device is known to support sparse multiple units,
1304 * override the other settings, and scan all of them. Normally,
1305 * SCSI-3 devices should be scanned via the REPORT LUNS.
1307 if (bflags & BLIST_SPARSELUN) {
1308 max_dev_lun = shost->max_lun;
1314 * If less than SCSI_1_CCS, and no special lun scanning, stop
1315 * scanning; this matches 2.4 behaviour, but could just be a bug
1316 * (to continue scanning a SCSI_1_CCS device).
1318 * This test is broken. We might not have any device on lun0 for
1319 * a sparselun device, and if that's the case then how would we
1320 * know the real scsi_level, eh? It might make sense to just not
1321 * scan any SCSI_1 device for non-0 luns, but that check would best
1322 * go into scsi_alloc_sdev() and just have it return null when asked
1323 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1325 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1326 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1331 * If this device is known to support multiple units, override
1332 * the other settings, and scan all of them.
1334 if (bflags & BLIST_FORCELUN)
1335 max_dev_lun = shost->max_lun;
1337 * REGAL CDC-4X: avoid hang after LUN 4
1339 if (bflags & BLIST_MAX5LUN)
1340 max_dev_lun = min(5U, max_dev_lun);
1342 * Do not scan SCSI-2 or lower device past LUN 7, unless
1345 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1346 max_dev_lun = min(8U, max_dev_lun);
1348 max_dev_lun = min(256U, max_dev_lun);
1351 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1352 * until we reach the max, or no LUN is found and we are not
1355 for (lun = 1; lun < max_dev_lun; ++lun)
1356 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1357 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1363 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1364 * @starget: which target
1365 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1366 * @rescan: nonzero if we can skip code only needed on first scan
1369 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1370 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1372 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1373 * LUNs even if it's older than SCSI-3.
1374 * If BLIST_NOREPORTLUN is set, return 1 always.
1375 * If BLIST_NOLUN is set, return 0 always.
1376 * If starget->no_report_luns is set, return 1 always.
1379 * 0: scan completed (or no memory, so further scanning is futile)
1380 * 1: could not scan with REPORT LUN
1382 static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflags,
1383 enum scsi_scan_mode rescan)
1385 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1386 unsigned int length;
1388 unsigned int num_luns;
1389 unsigned int retries;
1391 struct scsi_lun *lunp, *lun_data;
1392 struct scsi_sense_hdr sshdr;
1393 struct scsi_device *sdev;
1394 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1398 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1399 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1400 * support more than 8 LUNs.
1401 * Don't attempt if the target doesn't support REPORT LUNS.
1403 if (bflags & BLIST_NOREPORTLUN)
1405 if (starget->scsi_level < SCSI_2 &&
1406 starget->scsi_level != SCSI_UNKNOWN)
1408 if (starget->scsi_level < SCSI_3 &&
1409 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1411 if (bflags & BLIST_NOLUN)
1413 if (starget->no_report_luns)
1416 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1417 sdev = scsi_alloc_sdev(starget, 0, NULL);
1420 if (scsi_device_get(sdev)) {
1421 __scsi_remove_device(sdev);
1427 * Allocate enough to hold the header (the same size as one scsi_lun)
1428 * plus the number of luns we are requesting. 511 was the default
1429 * value of the now removed max_report_luns parameter.
1431 length = (511 + 1) * sizeof(struct scsi_lun);
1433 lun_data = kmalloc(length, GFP_KERNEL);
1435 printk(ALLOC_FAILURE_MSG, __func__);
1439 scsi_cmd[0] = REPORT_LUNS;
1442 * bytes 1 - 5: reserved, set to zero.
1444 memset(&scsi_cmd[1], 0, 5);
1447 * bytes 6 - 9: length of the command.
1449 put_unaligned_be32(length, &scsi_cmd[6]);
1451 scsi_cmd[10] = 0; /* reserved */
1452 scsi_cmd[11] = 0; /* control */
1455 * We can get a UNIT ATTENTION, for example a power on/reset, so
1456 * retry a few times (like sd.c does for TEST UNIT READY).
1457 * Experience shows some combinations of adapter/devices get at
1458 * least two power on/resets.
1460 * Illegal requests (for devices that do not support REPORT LUNS)
1461 * should come through as a check condition, and will not generate
1464 for (retries = 0; retries < 3; retries++) {
1465 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1466 "scsi scan: Sending REPORT LUNS to (try %d)\n",
1469 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1470 lun_data, length, &sshdr,
1471 SCSI_REPORT_LUNS_TIMEOUT, 3, NULL);
1473 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1474 "scsi scan: REPORT LUNS"
1475 " %s (try %d) result 0x%x\n",
1476 result ? "failed" : "successful",
1480 else if (scsi_sense_valid(&sshdr)) {
1481 if (sshdr.sense_key != UNIT_ATTENTION)
1488 * The device probably does not support a REPORT LUN command
1495 * Get the length from the first four bytes of lun_data.
1497 if (get_unaligned_be32(lun_data->scsi_lun) +
1498 sizeof(struct scsi_lun) > length) {
1499 length = get_unaligned_be32(lun_data->scsi_lun) +
1500 sizeof(struct scsi_lun);
1504 length = get_unaligned_be32(lun_data->scsi_lun);
1506 num_luns = (length / sizeof(struct scsi_lun));
1508 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1509 "scsi scan: REPORT LUN scan\n"));
1512 * Scan the luns in lun_data. The entry at offset 0 is really
1513 * the header, so start at 1 and go up to and including num_luns.
1515 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1516 lun = scsilun_to_int(lunp);
1518 if (lun > sdev->host->max_lun) {
1519 sdev_printk(KERN_WARNING, sdev,
1520 "lun%llu has a LUN larger than"
1521 " allowed by the host adapter\n", lun);
1525 res = scsi_probe_and_add_lun(starget,
1526 lun, NULL, NULL, rescan, NULL);
1527 if (res == SCSI_SCAN_NO_RESPONSE) {
1529 * Got some results, but now none, abort.
1531 sdev_printk(KERN_ERR, sdev,
1532 "Unexpected response"
1533 " from lun %llu while scanning, scan"
1534 " aborted\n", (unsigned long long)lun);
1543 if (scsi_device_created(sdev))
1545 * the sdev we used didn't appear in the report luns scan
1547 __scsi_remove_device(sdev);
1548 scsi_device_put(sdev);
1552 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1553 uint id, u64 lun, void *hostdata)
1555 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1556 struct device *parent = &shost->shost_gendev;
1557 struct scsi_target *starget;
1559 if (strncmp(scsi_scan_type, "none", 4) == 0)
1560 return ERR_PTR(-ENODEV);
1562 starget = scsi_alloc_target(parent, channel, id);
1564 return ERR_PTR(-ENOMEM);
1565 scsi_autopm_get_target(starget);
1567 mutex_lock(&shost->scan_mutex);
1568 if (!shost->async_scan)
1569 scsi_complete_async_scans();
1571 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1572 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1573 scsi_autopm_put_host(shost);
1575 mutex_unlock(&shost->scan_mutex);
1576 scsi_autopm_put_target(starget);
1578 * paired with scsi_alloc_target(). Target will be destroyed unless
1579 * scsi_probe_and_add_lun made an underlying device visible
1581 scsi_target_reap(starget);
1582 put_device(&starget->dev);
1586 EXPORT_SYMBOL(__scsi_add_device);
1588 int scsi_add_device(struct Scsi_Host *host, uint channel,
1589 uint target, u64 lun)
1591 struct scsi_device *sdev =
1592 __scsi_add_device(host, channel, target, lun, NULL);
1594 return PTR_ERR(sdev);
1596 scsi_device_put(sdev);
1599 EXPORT_SYMBOL(scsi_add_device);
1601 void scsi_rescan_device(struct device *dev)
1603 struct scsi_device *sdev = to_scsi_device(dev);
1607 scsi_attach_vpd(sdev);
1609 if (sdev->handler && sdev->handler->rescan)
1610 sdev->handler->rescan(sdev);
1612 if (dev->driver && try_module_get(dev->driver->owner)) {
1613 struct scsi_driver *drv = to_scsi_driver(dev->driver);
1617 module_put(dev->driver->owner);
1621 EXPORT_SYMBOL(scsi_rescan_device);
1623 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1624 unsigned int id, u64 lun, enum scsi_scan_mode rescan)
1626 struct Scsi_Host *shost = dev_to_shost(parent);
1627 blist_flags_t bflags = 0;
1629 struct scsi_target *starget;
1631 if (shost->this_id == id)
1633 * Don't scan the host adapter
1637 starget = scsi_alloc_target(parent, channel, id);
1640 scsi_autopm_get_target(starget);
1642 if (lun != SCAN_WILD_CARD) {
1644 * Scan for a specific host/chan/id/lun.
1646 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1651 * Scan LUN 0, if there is some response, scan further. Ideally, we
1652 * would not configure LUN 0 until all LUNs are scanned.
1654 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1655 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1656 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1658 * The REPORT LUN did not scan the target,
1659 * do a sequential scan.
1661 scsi_sequential_lun_scan(starget, bflags,
1662 starget->scsi_level, rescan);
1666 scsi_autopm_put_target(starget);
1668 * paired with scsi_alloc_target(): determine if the target has
1669 * any children at all and if not, nuke it
1671 scsi_target_reap(starget);
1673 put_device(&starget->dev);
1677 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1678 * @parent: host to scan
1679 * @channel: channel to scan
1680 * @id: target id to scan
1681 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1682 * @rescan: passed to LUN scanning routines; SCSI_SCAN_INITIAL for
1683 * no rescan, SCSI_SCAN_RESCAN to rescan existing LUNs,
1684 * and SCSI_SCAN_MANUAL to force scanning even if
1685 * 'scan=manual' is set.
1688 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1689 * and possibly all LUNs on the target id.
1691 * First try a REPORT LUN scan, if that does not scan the target, do a
1692 * sequential scan of LUNs on the target id.
1694 void scsi_scan_target(struct device *parent, unsigned int channel,
1695 unsigned int id, u64 lun, enum scsi_scan_mode rescan)
1697 struct Scsi_Host *shost = dev_to_shost(parent);
1699 if (strncmp(scsi_scan_type, "none", 4) == 0)
1702 if (rescan != SCSI_SCAN_MANUAL &&
1703 strncmp(scsi_scan_type, "manual", 6) == 0)
1706 mutex_lock(&shost->scan_mutex);
1707 if (!shost->async_scan)
1708 scsi_complete_async_scans();
1710 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1711 __scsi_scan_target(parent, channel, id, lun, rescan);
1712 scsi_autopm_put_host(shost);
1714 mutex_unlock(&shost->scan_mutex);
1716 EXPORT_SYMBOL(scsi_scan_target);
1718 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1719 unsigned int id, u64 lun,
1720 enum scsi_scan_mode rescan)
1724 if (id == SCAN_WILD_CARD)
1725 for (id = 0; id < shost->max_id; ++id) {
1727 * XXX adapter drivers when possible (FCP, iSCSI)
1728 * could modify max_id to match the current max,
1729 * not the absolute max.
1731 * XXX add a shost id iterator, so for example,
1732 * the FC ID can be the same as a target id
1733 * without a huge overhead of sparse id's.
1735 if (shost->reverse_ordering)
1737 * Scan from high to low id.
1739 order_id = shost->max_id - id - 1;
1742 __scsi_scan_target(&shost->shost_gendev, channel,
1743 order_id, lun, rescan);
1746 __scsi_scan_target(&shost->shost_gendev, channel,
1750 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1751 unsigned int id, u64 lun,
1752 enum scsi_scan_mode rescan)
1754 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1755 "%s: <%u:%u:%llu>\n",
1756 __func__, channel, id, lun));
1758 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1759 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1760 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun)))
1763 mutex_lock(&shost->scan_mutex);
1764 if (!shost->async_scan)
1765 scsi_complete_async_scans();
1767 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1768 if (channel == SCAN_WILD_CARD)
1769 for (channel = 0; channel <= shost->max_channel;
1771 scsi_scan_channel(shost, channel, id, lun,
1774 scsi_scan_channel(shost, channel, id, lun, rescan);
1775 scsi_autopm_put_host(shost);
1777 mutex_unlock(&shost->scan_mutex);
1782 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1784 struct scsi_device *sdev;
1785 shost_for_each_device(sdev, shost) {
1786 /* target removed before the device could be added */
1787 if (sdev->sdev_state == SDEV_DEL)
1789 /* If device is already visible, skip adding it to sysfs */
1790 if (sdev->is_visible)
1792 if (!scsi_host_scan_allowed(shost) ||
1793 scsi_sysfs_add_sdev(sdev) != 0)
1794 __scsi_remove_device(sdev);
1799 * scsi_prep_async_scan - prepare for an async scan
1800 * @shost: the host which will be scanned
1801 * Returns: a cookie to be passed to scsi_finish_async_scan()
1803 * Tells the midlayer this host is going to do an asynchronous scan.
1804 * It reserves the host's position in the scanning list and ensures
1805 * that other asynchronous scans started after this one won't affect the
1806 * ordering of the discovered devices.
1808 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1810 struct async_scan_data *data = NULL;
1811 unsigned long flags;
1813 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1816 mutex_lock(&shost->scan_mutex);
1817 if (shost->async_scan) {
1818 shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__);
1822 data = kmalloc(sizeof(*data), GFP_KERNEL);
1825 data->shost = scsi_host_get(shost);
1828 init_completion(&data->prev_finished);
1830 spin_lock_irqsave(shost->host_lock, flags);
1831 shost->async_scan = 1;
1832 spin_unlock_irqrestore(shost->host_lock, flags);
1833 mutex_unlock(&shost->scan_mutex);
1835 spin_lock(&async_scan_lock);
1836 if (list_empty(&scanning_hosts))
1837 complete(&data->prev_finished);
1838 list_add_tail(&data->list, &scanning_hosts);
1839 spin_unlock(&async_scan_lock);
1844 mutex_unlock(&shost->scan_mutex);
1850 * scsi_finish_async_scan - asynchronous scan has finished
1851 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1853 * All the devices currently attached to this host have been found.
1854 * This function announces all the devices it has found to the rest
1857 static void scsi_finish_async_scan(struct async_scan_data *data)
1859 struct Scsi_Host *shost;
1860 unsigned long flags;
1865 shost = data->shost;
1867 mutex_lock(&shost->scan_mutex);
1869 if (!shost->async_scan) {
1870 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
1872 mutex_unlock(&shost->scan_mutex);
1876 wait_for_completion(&data->prev_finished);
1878 scsi_sysfs_add_devices(shost);
1880 spin_lock_irqsave(shost->host_lock, flags);
1881 shost->async_scan = 0;
1882 spin_unlock_irqrestore(shost->host_lock, flags);
1884 mutex_unlock(&shost->scan_mutex);
1886 spin_lock(&async_scan_lock);
1887 list_del(&data->list);
1888 if (!list_empty(&scanning_hosts)) {
1889 struct async_scan_data *next = list_entry(scanning_hosts.next,
1890 struct async_scan_data, list);
1891 complete(&next->prev_finished);
1893 spin_unlock(&async_scan_lock);
1895 scsi_autopm_put_host(shost);
1896 scsi_host_put(shost);
1900 static void do_scsi_scan_host(struct Scsi_Host *shost)
1902 if (shost->hostt->scan_finished) {
1903 unsigned long start = jiffies;
1904 if (shost->hostt->scan_start)
1905 shost->hostt->scan_start(shost);
1907 while (!shost->hostt->scan_finished(shost, jiffies - start))
1910 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1915 static void do_scan_async(void *_data, async_cookie_t c)
1917 struct async_scan_data *data = _data;
1918 struct Scsi_Host *shost = data->shost;
1920 do_scsi_scan_host(shost);
1921 scsi_finish_async_scan(data);
1925 * scsi_scan_host - scan the given adapter
1926 * @shost: adapter to scan
1928 void scsi_scan_host(struct Scsi_Host *shost)
1930 struct async_scan_data *data;
1932 if (strncmp(scsi_scan_type, "none", 4) == 0 ||
1933 strncmp(scsi_scan_type, "manual", 6) == 0)
1935 if (scsi_autopm_get_host(shost) < 0)
1938 data = scsi_prep_async_scan(shost);
1940 do_scsi_scan_host(shost);
1941 scsi_autopm_put_host(shost);
1945 /* register with the async subsystem so wait_for_device_probe()
1946 * will flush this work
1948 async_schedule(do_scan_async, data);
1950 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
1952 EXPORT_SYMBOL(scsi_scan_host);
1954 void scsi_forget_host(struct Scsi_Host *shost)
1956 struct scsi_device *sdev;
1957 unsigned long flags;
1960 spin_lock_irqsave(shost->host_lock, flags);
1961 list_for_each_entry(sdev, &shost->__devices, siblings) {
1962 if (sdev->sdev_state == SDEV_DEL)
1964 spin_unlock_irqrestore(shost->host_lock, flags);
1965 __scsi_remove_device(sdev);
1968 spin_unlock_irqrestore(shost->host_lock, flags);