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 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_complete_async_scans - Wait for asynchronous scans to complete
128 * When this function returns, any host which started scanning before
129 * this function was called will have finished its scan. Hosts which
130 * started scanning after this function was called may or may not have
133 int scsi_complete_async_scans(void)
135 struct async_scan_data *data;
138 if (list_empty(&scanning_hosts))
140 /* If we can't get memory immediately, that's OK. Just
141 * sleep a little. Even if we never get memory, the async
142 * scans will finish eventually.
144 data = kmalloc(sizeof(*data), GFP_KERNEL);
150 init_completion(&data->prev_finished);
152 spin_lock(&async_scan_lock);
153 /* Check that there's still somebody else on the list */
154 if (list_empty(&scanning_hosts))
156 list_add_tail(&data->list, &scanning_hosts);
157 spin_unlock(&async_scan_lock);
159 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
160 wait_for_completion(&data->prev_finished);
162 spin_lock(&async_scan_lock);
163 list_del(&data->list);
164 if (!list_empty(&scanning_hosts)) {
165 struct async_scan_data *next = list_entry(scanning_hosts.next,
166 struct async_scan_data, list);
167 complete(&next->prev_finished);
170 spin_unlock(&async_scan_lock);
177 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
178 * @sdev: scsi device to send command to
179 * @result: area to store the result of the MODE SENSE
182 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
183 * Called for BLIST_KEY devices.
185 static void scsi_unlock_floptical(struct scsi_device *sdev,
186 unsigned char *result)
188 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
190 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n");
191 scsi_cmd[0] = MODE_SENSE;
195 scsi_cmd[4] = 0x2a; /* size */
197 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
198 SCSI_TIMEOUT, 3, NULL);
201 static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev,
204 int new_shift = sbitmap_calculate_shift(depth);
205 bool need_alloc = !sdev->budget_map.map;
206 bool need_free = false;
208 struct sbitmap sb_backup;
210 depth = min_t(unsigned int, depth, scsi_device_max_queue_depth(sdev));
213 * realloc if new shift is calculated, which is caused by setting
214 * up one new default queue depth after calling ->slave_configure
216 if (!need_alloc && new_shift != sdev->budget_map.shift)
217 need_alloc = need_free = true;
223 * Request queue has to be frozen for reallocating budget map,
224 * and here disk isn't added yet, so freezing is pretty fast
227 blk_mq_freeze_queue(sdev->request_queue);
228 sb_backup = sdev->budget_map;
230 ret = sbitmap_init_node(&sdev->budget_map,
231 scsi_device_max_queue_depth(sdev),
232 new_shift, GFP_KERNEL,
233 sdev->request_queue->node, false, true);
235 sbitmap_resize(&sdev->budget_map, depth);
239 sdev->budget_map = sb_backup;
241 sbitmap_free(&sb_backup);
243 blk_mq_unfreeze_queue(sdev->request_queue);
249 * scsi_alloc_sdev - allocate and setup a scsi_Device
250 * @starget: which target to allocate a &scsi_device for
252 * @hostdata: usually NULL and set by ->slave_alloc instead
255 * Allocate, initialize for io, and return a pointer to a scsi_Device.
256 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
257 * adds scsi_Device to the appropriate list.
260 * scsi_Device pointer, or NULL on failure.
262 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
263 u64 lun, void *hostdata)
266 struct scsi_device *sdev;
267 struct request_queue *q;
268 int display_failure_msg = 1, ret;
269 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
271 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
276 sdev->vendor = scsi_null_device_strs;
277 sdev->model = scsi_null_device_strs;
278 sdev->rev = scsi_null_device_strs;
280 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
281 sdev->id = starget->id;
283 sdev->channel = starget->channel;
284 mutex_init(&sdev->state_mutex);
285 sdev->sdev_state = SDEV_CREATED;
286 INIT_LIST_HEAD(&sdev->siblings);
287 INIT_LIST_HEAD(&sdev->same_target_siblings);
288 INIT_LIST_HEAD(&sdev->starved_entry);
289 INIT_LIST_HEAD(&sdev->event_list);
290 spin_lock_init(&sdev->list_lock);
291 mutex_init(&sdev->inquiry_mutex);
292 INIT_WORK(&sdev->event_work, scsi_evt_thread);
293 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
295 sdev->sdev_gendev.parent = get_device(&starget->dev);
296 sdev->sdev_target = starget;
298 /* usually NULL and set by ->slave_alloc instead */
299 sdev->hostdata = hostdata;
301 /* if the device needs this changing, it may do so in the
302 * slave_configure function */
303 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
306 * Some low level driver could use device->type
311 * Assume that the device will have handshaking problems,
312 * and then fix this field later if it turns out it
317 sdev->sg_reserved_size = INT_MAX;
319 q = blk_mq_init_queue(&sdev->host->tag_set);
321 /* release fn is set up in scsi_sysfs_device_initialise, so
322 * have to free and put manually here */
323 put_device(&starget->dev);
327 sdev->request_queue = q;
329 __scsi_init_queue(sdev->host, q);
330 blk_queue_flag_set(QUEUE_FLAG_SCSI_PASSTHROUGH, q);
331 WARN_ON_ONCE(!blk_get_queue(q));
333 depth = sdev->host->cmd_per_lun ?: 1;
336 * Use .can_queue as budget map's depth because we have to
337 * support adjusting queue depth from sysfs. Meantime use
338 * default device queue depth to figure out sbitmap shift
339 * since we use this queue depth most of times.
341 if (scsi_realloc_sdev_budget_map(sdev, depth)) {
342 put_device(&starget->dev);
347 scsi_change_queue_depth(sdev, depth);
349 scsi_sysfs_device_initialize(sdev);
351 if (shost->hostt->slave_alloc) {
352 ret = shost->hostt->slave_alloc(sdev);
355 * if LLDD reports slave not present, don't clutter
356 * console with alloc failure messages
359 display_failure_msg = 0;
360 goto out_device_destroy;
367 __scsi_remove_device(sdev);
369 if (display_failure_msg)
370 printk(ALLOC_FAILURE_MSG, __func__);
374 static void scsi_target_destroy(struct scsi_target *starget)
376 struct device *dev = &starget->dev;
377 struct Scsi_Host *shost = dev_to_shost(dev->parent);
380 BUG_ON(starget->state == STARGET_DEL);
381 starget->state = STARGET_DEL;
382 transport_destroy_device(dev);
383 spin_lock_irqsave(shost->host_lock, flags);
384 if (shost->hostt->target_destroy)
385 shost->hostt->target_destroy(starget);
386 list_del_init(&starget->siblings);
387 spin_unlock_irqrestore(shost->host_lock, flags);
391 static void scsi_target_dev_release(struct device *dev)
393 struct device *parent = dev->parent;
394 struct scsi_target *starget = to_scsi_target(dev);
400 static struct device_type scsi_target_type = {
401 .name = "scsi_target",
402 .release = scsi_target_dev_release,
405 int scsi_is_target_device(const struct device *dev)
407 return dev->type == &scsi_target_type;
409 EXPORT_SYMBOL(scsi_is_target_device);
411 static struct scsi_target *__scsi_find_target(struct device *parent,
412 int channel, uint id)
414 struct scsi_target *starget, *found_starget = NULL;
415 struct Scsi_Host *shost = dev_to_shost(parent);
417 * Search for an existing target for this sdev.
419 list_for_each_entry(starget, &shost->__targets, siblings) {
420 if (starget->id == id &&
421 starget->channel == channel) {
422 found_starget = starget;
427 get_device(&found_starget->dev);
429 return found_starget;
433 * scsi_target_reap_ref_release - remove target from visibility
434 * @kref: the reap_ref in the target being released
436 * Called on last put of reap_ref, which is the indication that no device
437 * under this target is visible anymore, so render the target invisible in
438 * sysfs. Note: we have to be in user context here because the target reaps
439 * should be done in places where the scsi device visibility is being removed.
441 static void scsi_target_reap_ref_release(struct kref *kref)
443 struct scsi_target *starget
444 = container_of(kref, struct scsi_target, reap_ref);
447 * if we get here and the target is still in a CREATED state that
448 * means it was allocated but never made visible (because a scan
449 * turned up no LUNs), so don't call device_del() on it.
451 if ((starget->state != STARGET_CREATED) &&
452 (starget->state != STARGET_CREATED_REMOVE)) {
453 transport_remove_device(&starget->dev);
454 device_del(&starget->dev);
456 scsi_target_destroy(starget);
459 static void scsi_target_reap_ref_put(struct scsi_target *starget)
461 kref_put(&starget->reap_ref, scsi_target_reap_ref_release);
465 * scsi_alloc_target - allocate a new or find an existing target
466 * @parent: parent of the target (need not be a scsi host)
467 * @channel: target channel number (zero if no channels)
468 * @id: target id number
470 * Return an existing target if one exists, provided it hasn't already
471 * gone into STARGET_DEL state, otherwise allocate a new target.
473 * The target is returned with an incremented reference, so the caller
474 * is responsible for both reaping and doing a last put
476 static struct scsi_target *scsi_alloc_target(struct device *parent,
477 int channel, uint id)
479 struct Scsi_Host *shost = dev_to_shost(parent);
480 struct device *dev = NULL;
482 const int size = sizeof(struct scsi_target)
483 + shost->transportt->target_size;
484 struct scsi_target *starget;
485 struct scsi_target *found_target;
488 starget = kzalloc(size, GFP_KERNEL);
490 printk(KERN_ERR "%s: allocation failure\n", __func__);
494 device_initialize(dev);
495 kref_init(&starget->reap_ref);
496 dev->parent = get_device(parent);
497 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
498 dev->bus = &scsi_bus_type;
499 dev->type = &scsi_target_type;
501 starget->channel = channel;
502 starget->can_queue = 0;
503 INIT_LIST_HEAD(&starget->siblings);
504 INIT_LIST_HEAD(&starget->devices);
505 starget->state = STARGET_CREATED;
506 starget->scsi_level = SCSI_2;
507 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
509 spin_lock_irqsave(shost->host_lock, flags);
511 found_target = __scsi_find_target(parent, channel, id);
515 list_add_tail(&starget->siblings, &shost->__targets);
516 spin_unlock_irqrestore(shost->host_lock, flags);
517 /* allocate and add */
518 transport_setup_device(dev);
519 if (shost->hostt->target_alloc) {
520 error = shost->hostt->target_alloc(starget);
524 dev_err(dev, "target allocation failed, error %d\n", error);
525 /* don't want scsi_target_reap to do the final
526 * put because it will be under the host lock */
527 scsi_target_destroy(starget);
537 * release routine already fired if kref is zero, so if we can still
538 * take the reference, the target must be alive. If we can't, it must
539 * be dying and we need to wait for a new target
541 ref_got = kref_get_unless_zero(&found_target->reap_ref);
543 spin_unlock_irqrestore(shost->host_lock, flags);
549 * Unfortunately, we found a dying target; need to wait until it's
550 * dead before we can get a new one. There is an anomaly here. We
551 * *should* call scsi_target_reap() to balance the kref_get() of the
552 * reap_ref above. However, since the target being released, it's
553 * already invisible and the reap_ref is irrelevant. If we call
554 * scsi_target_reap() we might spuriously do another device_del() on
555 * an already invisible target.
557 put_device(&found_target->dev);
559 * length of time is irrelevant here, we just want to yield the CPU
560 * for a tick to avoid busy waiting for the target to die.
567 * scsi_target_reap - check to see if target is in use and destroy if not
568 * @starget: target to be checked
570 * This is used after removing a LUN or doing a last put of the target
571 * it checks atomically that nothing is using the target and removes
574 void scsi_target_reap(struct scsi_target *starget)
577 * serious problem if this triggers: STARGET_DEL is only set in the if
578 * the reap_ref drops to zero, so we're trying to do another final put
579 * on an already released kref
581 BUG_ON(starget->state == STARGET_DEL);
582 scsi_target_reap_ref_put(starget);
586 * scsi_sanitize_inquiry_string - remove non-graphical chars from an
587 * INQUIRY result string
588 * @s: INQUIRY result string to sanitize
589 * @len: length of the string
592 * The SCSI spec says that INQUIRY vendor, product, and revision
593 * strings must consist entirely of graphic ASCII characters,
594 * padded on the right with spaces. Since not all devices obey
595 * this rule, we will replace non-graphic or non-ASCII characters
596 * with spaces. Exception: a NUL character is interpreted as a
597 * string terminator, so all the following characters are set to
600 void scsi_sanitize_inquiry_string(unsigned char *s, int len)
604 for (; len > 0; (--len, ++s)) {
607 if (terminated || *s < 0x20 || *s > 0x7e)
611 EXPORT_SYMBOL(scsi_sanitize_inquiry_string);
614 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
615 * @sdev: scsi_device to probe
616 * @inq_result: area to store the INQUIRY result
617 * @result_len: len of inq_result
618 * @bflags: store any bflags found here
621 * Probe the lun associated with @req using a standard SCSI INQUIRY;
623 * If the INQUIRY is successful, zero is returned and the
624 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
625 * are copied to the scsi_device any flags value is stored in *@bflags.
627 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
628 int result_len, blist_flags_t *bflags)
630 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
631 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
632 int response_len = 0;
633 int pass, count, result;
634 struct scsi_sense_hdr sshdr;
638 /* Perform up to 3 passes. The first pass uses a conservative
639 * transfer length of 36 unless sdev->inquiry_len specifies a
640 * different value. */
641 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
642 try_inquiry_len = first_inquiry_len;
646 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
647 "scsi scan: INQUIRY pass %d length %d\n",
648 pass, try_inquiry_len));
650 /* Each pass gets up to three chances to ignore Unit Attention */
651 for (count = 0; count < 3; ++count) {
654 memset(scsi_cmd, 0, 6);
655 scsi_cmd[0] = INQUIRY;
656 scsi_cmd[4] = (unsigned char) try_inquiry_len;
658 memset(inq_result, 0, try_inquiry_len);
660 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
661 inq_result, try_inquiry_len, &sshdr,
662 HZ / 2 + HZ * scsi_inq_timeout, 3,
665 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
666 "scsi scan: INQUIRY %s with code 0x%x\n",
667 result ? "failed" : "successful", result));
671 * not-ready to ready transition [asc/ascq=0x28/0x0]
672 * or power-on, reset [asc/ascq=0x29/0x0], continue.
673 * INQUIRY should not yield UNIT_ATTENTION
674 * but many buggy devices do so anyway.
676 if (scsi_status_is_check_condition(result) &&
677 scsi_sense_valid(&sshdr)) {
678 if ((sshdr.sense_key == UNIT_ATTENTION) &&
679 ((sshdr.asc == 0x28) ||
680 (sshdr.asc == 0x29)) &&
684 } else if (result == 0) {
686 * if nothing was transferred, we try
687 * again. It's a workaround for some USB
690 if (resid == try_inquiry_len)
697 scsi_sanitize_inquiry_string(&inq_result[8], 8);
698 scsi_sanitize_inquiry_string(&inq_result[16], 16);
699 scsi_sanitize_inquiry_string(&inq_result[32], 4);
701 response_len = inq_result[4] + 5;
702 if (response_len > 255)
703 response_len = first_inquiry_len; /* sanity */
706 * Get any flags for this device.
708 * XXX add a bflags to scsi_device, and replace the
709 * corresponding bit fields in scsi_device, so bflags
710 * need not be passed as an argument.
712 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
715 /* When the first pass succeeds we gain information about
716 * what larger transfer lengths might work. */
718 if (BLIST_INQUIRY_36 & *bflags)
719 next_inquiry_len = 36;
720 else if (sdev->inquiry_len)
721 next_inquiry_len = sdev->inquiry_len;
723 next_inquiry_len = response_len;
725 /* If more data is available perform the second pass */
726 if (next_inquiry_len > try_inquiry_len) {
727 try_inquiry_len = next_inquiry_len;
733 } else if (pass == 2) {
734 sdev_printk(KERN_INFO, sdev,
735 "scsi scan: %d byte inquiry failed. "
736 "Consider BLIST_INQUIRY_36 for this device\n",
739 /* If this pass failed, the third pass goes back and transfers
740 * the same amount as we successfully got in the first pass. */
741 try_inquiry_len = first_inquiry_len;
746 /* If the last transfer attempt got an error, assume the
747 * peripheral doesn't exist or is dead. */
751 /* Don't report any more data than the device says is valid */
752 sdev->inquiry_len = min(try_inquiry_len, response_len);
755 * XXX Abort if the response length is less than 36? If less than
756 * 32, the lookup of the device flags (above) could be invalid,
757 * and it would be possible to take an incorrect action - we do
758 * not want to hang because of a short INQUIRY. On the flip side,
759 * if the device is spun down or becoming ready (and so it gives a
760 * short INQUIRY), an abort here prevents any further use of the
761 * device, including spin up.
763 * On the whole, the best approach seems to be to assume the first
764 * 36 bytes are valid no matter what the device says. That's
765 * better than copying < 36 bytes to the inquiry-result buffer
766 * and displaying garbage for the Vendor, Product, or Revision
769 if (sdev->inquiry_len < 36) {
770 if (!sdev->host->short_inquiry) {
771 shost_printk(KERN_INFO, sdev->host,
772 "scsi scan: INQUIRY result too short (%d),"
773 " using 36\n", sdev->inquiry_len);
774 sdev->host->short_inquiry = 1;
776 sdev->inquiry_len = 36;
780 * Related to the above issue:
782 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
783 * and if not ready, sent a START_STOP to start (maybe spin up) and
784 * then send the INQUIRY again, since the INQUIRY can change after
785 * a device is initialized.
787 * Ideally, start a device if explicitly asked to do so. This
788 * assumes that a device is spun up on power on, spun down on
789 * request, and then spun up on request.
793 * The scanning code needs to know the scsi_level, even if no
794 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
795 * non-zero LUNs can be scanned.
797 sdev->scsi_level = inq_result[2] & 0x07;
798 if (sdev->scsi_level >= 2 ||
799 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
801 sdev->sdev_target->scsi_level = sdev->scsi_level;
804 * If SCSI-2 or lower, and if the transport requires it,
805 * store the LUN value in CDB[1].
807 sdev->lun_in_cdb = 0;
808 if (sdev->scsi_level <= SCSI_2 &&
809 sdev->scsi_level != SCSI_UNKNOWN &&
810 !sdev->host->no_scsi2_lun_in_cdb)
811 sdev->lun_in_cdb = 1;
817 * scsi_add_lun - allocate and fully initialze a scsi_device
818 * @sdev: holds information to be stored in the new scsi_device
819 * @inq_result: holds the result of a previous INQUIRY to the LUN
820 * @bflags: black/white list flag
821 * @async: 1 if this device is being scanned asynchronously
824 * Initialize the scsi_device @sdev. Optionally set fields based
825 * on values in *@bflags.
828 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
829 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
831 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
832 blist_flags_t *bflags, int async)
837 * XXX do not save the inquiry, since it can change underneath us,
838 * save just vendor/model/rev.
840 * Rather than save it and have an ioctl that retrieves the saved
841 * value, have an ioctl that executes the same INQUIRY code used
842 * in scsi_probe_lun, let user level programs doing INQUIRY
843 * scanning run at their own risk, or supply a user level program
844 * that can correctly scan.
848 * Copy at least 36 bytes of INQUIRY data, so that we don't
849 * dereference unallocated memory when accessing the Vendor,
850 * Product, and Revision strings. Badly behaved devices may set
851 * the INQUIRY Additional Length byte to a small value, indicating
852 * these strings are invalid, but often they contain plausible data
853 * nonetheless. It doesn't matter if the device sent < 36 bytes
854 * total, since scsi_probe_lun() initializes inq_result with 0s.
856 sdev->inquiry = kmemdup(inq_result,
857 max_t(size_t, sdev->inquiry_len, 36),
859 if (sdev->inquiry == NULL)
860 return SCSI_SCAN_NO_RESPONSE;
862 sdev->vendor = (char *) (sdev->inquiry + 8);
863 sdev->model = (char *) (sdev->inquiry + 16);
864 sdev->rev = (char *) (sdev->inquiry + 32);
866 if (strncmp(sdev->vendor, "ATA ", 8) == 0) {
868 * sata emulation layer device. This is a hack to work around
869 * the SATL power management specifications which state that
870 * when the SATL detects the device has gone into standby
871 * mode, it shall respond with NOT READY.
873 sdev->allow_restart = 1;
876 if (*bflags & BLIST_ISROM) {
877 sdev->type = TYPE_ROM;
880 sdev->type = (inq_result[0] & 0x1f);
881 sdev->removable = (inq_result[1] & 0x80) >> 7;
884 * some devices may respond with wrong type for
885 * well-known logical units. Force well-known type
886 * to enumerate them correctly.
888 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) {
889 sdev_printk(KERN_WARNING, sdev,
890 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n",
891 __func__, sdev->type, (unsigned int)sdev->lun);
892 sdev->type = TYPE_WLUN;
897 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
898 /* RBC and MMC devices can return SCSI-3 compliance and yet
899 * still not support REPORT LUNS, so make them act as
900 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
901 * specifically set */
902 if ((*bflags & BLIST_REPORTLUN2) == 0)
903 *bflags |= BLIST_NOREPORTLUN;
907 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
908 * spec says: The device server is capable of supporting the
909 * specified peripheral device type on this logical unit. However,
910 * the physical device is not currently connected to this logical
913 * The above is vague, as it implies that we could treat 001 and
914 * 011 the same. Stay compatible with previous code, and create a
915 * scsi_device for a PQ of 1
917 * Don't set the device offline here; rather let the upper
918 * level drivers eval the PQ to decide whether they should
919 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
922 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
923 sdev->lockable = sdev->removable;
924 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
926 if (sdev->scsi_level >= SCSI_3 ||
927 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
929 if (inq_result[7] & 0x60)
931 if (inq_result[7] & 0x10)
934 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
935 "ANSI: %d%s\n", scsi_device_type(sdev->type),
936 sdev->vendor, sdev->model, sdev->rev,
937 sdev->inq_periph_qual, inq_result[2] & 0x07,
938 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
940 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
941 !(*bflags & BLIST_NOTQ)) {
942 sdev->tagged_supported = 1;
943 sdev->simple_tags = 1;
947 * Some devices (Texel CD ROM drives) have handshaking problems
948 * when used with the Seagate controllers. borken is initialized
949 * to 1, and then set it to 0 here.
951 if ((*bflags & BLIST_BORKEN) == 0)
954 if (*bflags & BLIST_NO_ULD_ATTACH)
955 sdev->no_uld_attach = 1;
958 * Apparently some really broken devices (contrary to the SCSI
959 * standards) need to be selected without asserting ATN
961 if (*bflags & BLIST_SELECT_NO_ATN)
962 sdev->select_no_atn = 1;
965 * Maximum 512 sector transfer length
966 * broken RA4x00 Compaq Disk Array
968 if (*bflags & BLIST_MAX_512)
969 blk_queue_max_hw_sectors(sdev->request_queue, 512);
971 * Max 1024 sector transfer length for targets that report incorrect
972 * max/optimal lengths and relied on the old block layer safe default
974 else if (*bflags & BLIST_MAX_1024)
975 blk_queue_max_hw_sectors(sdev->request_queue, 1024);
978 * Some devices may not want to have a start command automatically
979 * issued when a device is added.
981 if (*bflags & BLIST_NOSTARTONADD)
982 sdev->no_start_on_add = 1;
984 if (*bflags & BLIST_SINGLELUN)
985 scsi_target(sdev)->single_lun = 1;
987 sdev->use_10_for_rw = 1;
989 /* some devices don't like REPORT SUPPORTED OPERATION CODES
990 * and will simply timeout causing sd_mod init to take a very
992 if (*bflags & BLIST_NO_RSOC)
993 sdev->no_report_opcodes = 1;
995 /* set the device running here so that slave configure
997 mutex_lock(&sdev->state_mutex);
998 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
1000 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
1001 mutex_unlock(&sdev->state_mutex);
1004 sdev_printk(KERN_ERR, sdev,
1005 "in wrong state %s to complete scan\n",
1006 scsi_device_state_name(sdev->sdev_state));
1007 return SCSI_SCAN_NO_RESPONSE;
1010 if (*bflags & BLIST_NOT_LOCKABLE)
1013 if (*bflags & BLIST_RETRY_HWERROR)
1014 sdev->retry_hwerror = 1;
1016 if (*bflags & BLIST_NO_DIF)
1019 if (*bflags & BLIST_UNMAP_LIMIT_WS)
1020 sdev->unmap_limit_for_ws = 1;
1022 if (*bflags & BLIST_IGN_MEDIA_CHANGE)
1023 sdev->ignore_media_change = 1;
1025 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
1027 if (*bflags & BLIST_TRY_VPD_PAGES)
1028 sdev->try_vpd_pages = 1;
1029 else if (*bflags & BLIST_SKIP_VPD_PAGES)
1030 sdev->skip_vpd_pages = 1;
1032 transport_configure_device(&sdev->sdev_gendev);
1034 if (sdev->host->hostt->slave_configure) {
1035 ret = sdev->host->hostt->slave_configure(sdev);
1038 * if LLDD reports slave not present, don't clutter
1039 * console with alloc failure messages
1041 if (ret != -ENXIO) {
1042 sdev_printk(KERN_ERR, sdev,
1043 "failed to configure device\n");
1045 return SCSI_SCAN_NO_RESPONSE;
1049 * The queue_depth is often changed in ->slave_configure.
1050 * Set up budget map again since memory consumption of
1051 * the map depends on actual queue depth.
1053 scsi_realloc_sdev_budget_map(sdev, sdev->queue_depth);
1056 if (sdev->scsi_level >= SCSI_3)
1057 scsi_attach_vpd(sdev);
1059 sdev->max_queue_depth = sdev->queue_depth;
1060 WARN_ON_ONCE(sdev->max_queue_depth > sdev->budget_map.depth);
1061 sdev->sdev_bflags = *bflags;
1064 * Ok, the device is now all set up, we can
1065 * register it and tell the rest of the kernel
1068 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
1069 return SCSI_SCAN_NO_RESPONSE;
1071 return SCSI_SCAN_LUN_PRESENT;
1074 #ifdef CONFIG_SCSI_LOGGING
1076 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
1077 * @buf: Output buffer with at least end-first+1 bytes of space
1078 * @inq: Inquiry buffer (input)
1079 * @first: Offset of string into inq
1080 * @end: Index after last character in inq
1082 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
1083 unsigned first, unsigned end)
1085 unsigned term = 0, idx;
1087 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
1088 if (inq[idx+first] > ' ') {
1089 buf[idx] = inq[idx+first];
1101 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
1102 * @starget: pointer to target device structure
1103 * @lun: LUN of target device
1104 * @bflagsp: store bflags here if not NULL
1105 * @sdevp: probe the LUN corresponding to this scsi_device
1106 * @rescan: if not equal to SCSI_SCAN_INITIAL skip some code only
1107 * needed on first scan
1108 * @hostdata: passed to scsi_alloc_sdev()
1111 * Call scsi_probe_lun, if a LUN with an attached device is found,
1112 * allocate and set it up by calling scsi_add_lun.
1116 * - SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1117 * - SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1118 * attached at the LUN
1119 * - SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1121 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1122 u64 lun, blist_flags_t *bflagsp,
1123 struct scsi_device **sdevp,
1124 enum scsi_scan_mode rescan,
1127 struct scsi_device *sdev;
1128 unsigned char *result;
1129 blist_flags_t bflags;
1130 int res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1131 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1134 * The rescan flag is used as an optimization, the first scan of a
1135 * host adapter calls into here with rescan == 0.
1137 sdev = scsi_device_lookup_by_target(starget, lun);
1139 if (rescan != SCSI_SCAN_INITIAL || !scsi_device_created(sdev)) {
1140 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1141 "scsi scan: device exists on %s\n",
1142 dev_name(&sdev->sdev_gendev)));
1146 scsi_device_put(sdev);
1149 *bflagsp = scsi_get_device_flags(sdev,
1152 return SCSI_SCAN_LUN_PRESENT;
1154 scsi_device_put(sdev);
1156 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1160 result = kmalloc(result_len, GFP_KERNEL);
1164 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1165 goto out_free_result;
1170 * result contains valid SCSI INQUIRY data.
1172 if ((result[0] >> 5) == 3) {
1174 * For a Peripheral qualifier 3 (011b), the SCSI
1175 * spec says: The device server is not capable of
1176 * supporting a physical device on this logical
1179 * For disks, this implies that there is no
1180 * logical disk configured at sdev->lun, but there
1181 * is a target id responding.
1183 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1184 " peripheral qualifier of 3, device not"
1187 SCSI_LOG_SCAN_BUS(1, {
1188 unsigned char vend[9];
1189 unsigned char mod[17];
1191 sdev_printk(KERN_INFO, sdev,
1192 "scsi scan: consider passing scsi_mod."
1193 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1194 scsi_inq_str(vend, result, 8, 16),
1195 scsi_inq_str(mod, result, 16, 32));
1200 res = SCSI_SCAN_TARGET_PRESENT;
1201 goto out_free_result;
1205 * Some targets may set slight variations of PQ and PDT to signal
1206 * that no LUN is present, so don't add sdev in these cases.
1207 * Two specific examples are:
1208 * 1) NetApp targets: return PQ=1, PDT=0x1f
1209 * 2) IBM/2145 targets: return PQ=1, PDT=0
1210 * 3) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1211 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1214 * 1) SCSI SPC-3, pp. 145-146
1215 * PQ=1: "A peripheral device having the specified peripheral
1216 * device type is not connected to this logical unit. However, the
1217 * device server is capable of supporting the specified peripheral
1218 * device type on this logical unit."
1219 * PDT=0x1f: "Unknown or no device type"
1220 * 2) USB UFI 1.0, p. 20
1221 * PDT=00h Direct-access device (floppy)
1222 * PDT=1Fh none (no FDD connected to the requested logical unit)
1224 if (((result[0] >> 5) == 1 ||
1225 (starget->pdt_1f_for_no_lun && (result[0] & 0x1f) == 0x1f)) &&
1226 !scsi_is_wlun(lun)) {
1227 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1228 "scsi scan: peripheral device type"
1229 " of 31, no device added\n"));
1230 res = SCSI_SCAN_TARGET_PRESENT;
1231 goto out_free_result;
1234 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1235 if (res == SCSI_SCAN_LUN_PRESENT) {
1236 if (bflags & BLIST_KEY) {
1238 scsi_unlock_floptical(sdev, result);
1245 if (res == SCSI_SCAN_LUN_PRESENT) {
1247 if (scsi_device_get(sdev) == 0) {
1250 __scsi_remove_device(sdev);
1251 res = SCSI_SCAN_NO_RESPONSE;
1255 __scsi_remove_device(sdev);
1261 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1262 * @starget: pointer to target structure to scan
1263 * @bflags: black/white list flag for LUN 0
1264 * @scsi_level: Which version of the standard does this device adhere to
1265 * @rescan: passed to scsi_probe_add_lun()
1268 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1269 * scanned) to some maximum lun until a LUN is found with no device
1270 * attached. Use the bflags to figure out any oddities.
1272 * Modifies sdevscan->lun.
1274 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1275 blist_flags_t bflags, int scsi_level,
1276 enum scsi_scan_mode rescan)
1279 u64 sparse_lun, lun;
1280 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1282 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget,
1283 "scsi scan: Sequential scan\n"));
1285 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1287 * If this device is known to support sparse multiple units,
1288 * override the other settings, and scan all of them. Normally,
1289 * SCSI-3 devices should be scanned via the REPORT LUNS.
1291 if (bflags & BLIST_SPARSELUN) {
1292 max_dev_lun = shost->max_lun;
1298 * If less than SCSI_1_CCS, and no special lun scanning, stop
1299 * scanning; this matches 2.4 behaviour, but could just be a bug
1300 * (to continue scanning a SCSI_1_CCS device).
1302 * This test is broken. We might not have any device on lun0 for
1303 * a sparselun device, and if that's the case then how would we
1304 * know the real scsi_level, eh? It might make sense to just not
1305 * scan any SCSI_1 device for non-0 luns, but that check would best
1306 * go into scsi_alloc_sdev() and just have it return null when asked
1307 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1309 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1310 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1315 * If this device is known to support multiple units, override
1316 * the other settings, and scan all of them.
1318 if (bflags & BLIST_FORCELUN)
1319 max_dev_lun = shost->max_lun;
1321 * REGAL CDC-4X: avoid hang after LUN 4
1323 if (bflags & BLIST_MAX5LUN)
1324 max_dev_lun = min(5U, max_dev_lun);
1326 * Do not scan SCSI-2 or lower device past LUN 7, unless
1329 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1330 max_dev_lun = min(8U, max_dev_lun);
1332 max_dev_lun = min(256U, max_dev_lun);
1335 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1336 * until we reach the max, or no LUN is found and we are not
1339 for (lun = 1; lun < max_dev_lun; ++lun)
1340 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1341 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1347 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1348 * @starget: which target
1349 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1350 * @rescan: nonzero if we can skip code only needed on first scan
1353 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1354 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1356 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1357 * LUNs even if it's older than SCSI-3.
1358 * If BLIST_NOREPORTLUN is set, return 1 always.
1359 * If BLIST_NOLUN is set, return 0 always.
1360 * If starget->no_report_luns is set, return 1 always.
1363 * 0: scan completed (or no memory, so further scanning is futile)
1364 * 1: could not scan with REPORT LUN
1366 static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflags,
1367 enum scsi_scan_mode rescan)
1369 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1370 unsigned int length;
1372 unsigned int num_luns;
1373 unsigned int retries;
1375 struct scsi_lun *lunp, *lun_data;
1376 struct scsi_sense_hdr sshdr;
1377 struct scsi_device *sdev;
1378 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1382 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1383 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1384 * support more than 8 LUNs.
1385 * Don't attempt if the target doesn't support REPORT LUNS.
1387 if (bflags & BLIST_NOREPORTLUN)
1389 if (starget->scsi_level < SCSI_2 &&
1390 starget->scsi_level != SCSI_UNKNOWN)
1392 if (starget->scsi_level < SCSI_3 &&
1393 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1395 if (bflags & BLIST_NOLUN)
1397 if (starget->no_report_luns)
1400 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1401 sdev = scsi_alloc_sdev(starget, 0, NULL);
1404 if (scsi_device_get(sdev)) {
1405 __scsi_remove_device(sdev);
1411 * Allocate enough to hold the header (the same size as one scsi_lun)
1412 * plus the number of luns we are requesting. 511 was the default
1413 * value of the now removed max_report_luns parameter.
1415 length = (511 + 1) * sizeof(struct scsi_lun);
1417 lun_data = kmalloc(length, GFP_KERNEL);
1419 printk(ALLOC_FAILURE_MSG, __func__);
1423 scsi_cmd[0] = REPORT_LUNS;
1426 * bytes 1 - 5: reserved, set to zero.
1428 memset(&scsi_cmd[1], 0, 5);
1431 * bytes 6 - 9: length of the command.
1433 put_unaligned_be32(length, &scsi_cmd[6]);
1435 scsi_cmd[10] = 0; /* reserved */
1436 scsi_cmd[11] = 0; /* control */
1439 * We can get a UNIT ATTENTION, for example a power on/reset, so
1440 * retry a few times (like sd.c does for TEST UNIT READY).
1441 * Experience shows some combinations of adapter/devices get at
1442 * least two power on/resets.
1444 * Illegal requests (for devices that do not support REPORT LUNS)
1445 * should come through as a check condition, and will not generate
1448 for (retries = 0; retries < 3; retries++) {
1449 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1450 "scsi scan: Sending REPORT LUNS to (try %d)\n",
1453 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1454 lun_data, length, &sshdr,
1455 SCSI_REPORT_LUNS_TIMEOUT, 3, NULL);
1457 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1458 "scsi scan: REPORT LUNS"
1459 " %s (try %d) result 0x%x\n",
1460 result ? "failed" : "successful",
1464 else if (scsi_sense_valid(&sshdr)) {
1465 if (sshdr.sense_key != UNIT_ATTENTION)
1472 * The device probably does not support a REPORT LUN command
1479 * Get the length from the first four bytes of lun_data.
1481 if (get_unaligned_be32(lun_data->scsi_lun) +
1482 sizeof(struct scsi_lun) > length) {
1483 length = get_unaligned_be32(lun_data->scsi_lun) +
1484 sizeof(struct scsi_lun);
1488 length = get_unaligned_be32(lun_data->scsi_lun);
1490 num_luns = (length / sizeof(struct scsi_lun));
1492 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1493 "scsi scan: REPORT LUN scan\n"));
1496 * Scan the luns in lun_data. The entry at offset 0 is really
1497 * the header, so start at 1 and go up to and including num_luns.
1499 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1500 lun = scsilun_to_int(lunp);
1502 if (lun > sdev->host->max_lun) {
1503 sdev_printk(KERN_WARNING, sdev,
1504 "lun%llu has a LUN larger than"
1505 " allowed by the host adapter\n", lun);
1509 res = scsi_probe_and_add_lun(starget,
1510 lun, NULL, NULL, rescan, NULL);
1511 if (res == SCSI_SCAN_NO_RESPONSE) {
1513 * Got some results, but now none, abort.
1515 sdev_printk(KERN_ERR, sdev,
1516 "Unexpected response"
1517 " from lun %llu while scanning, scan"
1518 " aborted\n", (unsigned long long)lun);
1527 if (scsi_device_created(sdev))
1529 * the sdev we used didn't appear in the report luns scan
1531 __scsi_remove_device(sdev);
1532 scsi_device_put(sdev);
1536 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1537 uint id, u64 lun, void *hostdata)
1539 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1540 struct device *parent = &shost->shost_gendev;
1541 struct scsi_target *starget;
1543 if (strncmp(scsi_scan_type, "none", 4) == 0)
1544 return ERR_PTR(-ENODEV);
1546 starget = scsi_alloc_target(parent, channel, id);
1548 return ERR_PTR(-ENOMEM);
1549 scsi_autopm_get_target(starget);
1551 mutex_lock(&shost->scan_mutex);
1552 if (!shost->async_scan)
1553 scsi_complete_async_scans();
1555 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1556 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1557 scsi_autopm_put_host(shost);
1559 mutex_unlock(&shost->scan_mutex);
1560 scsi_autopm_put_target(starget);
1562 * paired with scsi_alloc_target(). Target will be destroyed unless
1563 * scsi_probe_and_add_lun made an underlying device visible
1565 scsi_target_reap(starget);
1566 put_device(&starget->dev);
1570 EXPORT_SYMBOL(__scsi_add_device);
1572 int scsi_add_device(struct Scsi_Host *host, uint channel,
1573 uint target, u64 lun)
1575 struct scsi_device *sdev =
1576 __scsi_add_device(host, channel, target, lun, NULL);
1578 return PTR_ERR(sdev);
1580 scsi_device_put(sdev);
1583 EXPORT_SYMBOL(scsi_add_device);
1585 void scsi_rescan_device(struct device *dev)
1587 struct scsi_device *sdev = to_scsi_device(dev);
1591 scsi_attach_vpd(sdev);
1593 if (sdev->handler && sdev->handler->rescan)
1594 sdev->handler->rescan(sdev);
1596 if (dev->driver && try_module_get(dev->driver->owner)) {
1597 struct scsi_driver *drv = to_scsi_driver(dev->driver);
1601 module_put(dev->driver->owner);
1605 EXPORT_SYMBOL(scsi_rescan_device);
1607 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1608 unsigned int id, u64 lun, enum scsi_scan_mode rescan)
1610 struct Scsi_Host *shost = dev_to_shost(parent);
1611 blist_flags_t bflags = 0;
1613 struct scsi_target *starget;
1615 if (shost->this_id == id)
1617 * Don't scan the host adapter
1621 starget = scsi_alloc_target(parent, channel, id);
1624 scsi_autopm_get_target(starget);
1626 if (lun != SCAN_WILD_CARD) {
1628 * Scan for a specific host/chan/id/lun.
1630 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1635 * Scan LUN 0, if there is some response, scan further. Ideally, we
1636 * would not configure LUN 0 until all LUNs are scanned.
1638 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1639 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1640 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1642 * The REPORT LUN did not scan the target,
1643 * do a sequential scan.
1645 scsi_sequential_lun_scan(starget, bflags,
1646 starget->scsi_level, rescan);
1650 scsi_autopm_put_target(starget);
1652 * paired with scsi_alloc_target(): determine if the target has
1653 * any children at all and if not, nuke it
1655 scsi_target_reap(starget);
1657 put_device(&starget->dev);
1661 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1662 * @parent: host to scan
1663 * @channel: channel to scan
1664 * @id: target id to scan
1665 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1666 * @rescan: passed to LUN scanning routines; SCSI_SCAN_INITIAL for
1667 * no rescan, SCSI_SCAN_RESCAN to rescan existing LUNs,
1668 * and SCSI_SCAN_MANUAL to force scanning even if
1669 * 'scan=manual' is set.
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, enum scsi_scan_mode rescan)
1681 struct Scsi_Host *shost = dev_to_shost(parent);
1683 if (strncmp(scsi_scan_type, "none", 4) == 0)
1686 if (rescan != SCSI_SCAN_MANUAL &&
1687 strncmp(scsi_scan_type, "manual", 6) == 0)
1690 mutex_lock(&shost->scan_mutex);
1691 if (!shost->async_scan)
1692 scsi_complete_async_scans();
1694 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1695 __scsi_scan_target(parent, channel, id, lun, rescan);
1696 scsi_autopm_put_host(shost);
1698 mutex_unlock(&shost->scan_mutex);
1700 EXPORT_SYMBOL(scsi_scan_target);
1702 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1703 unsigned int id, u64 lun,
1704 enum scsi_scan_mode rescan)
1708 if (id == SCAN_WILD_CARD)
1709 for (id = 0; id < shost->max_id; ++id) {
1711 * XXX adapter drivers when possible (FCP, iSCSI)
1712 * could modify max_id to match the current max,
1713 * not the absolute max.
1715 * XXX add a shost id iterator, so for example,
1716 * the FC ID can be the same as a target id
1717 * without a huge overhead of sparse id's.
1719 if (shost->reverse_ordering)
1721 * Scan from high to low id.
1723 order_id = shost->max_id - id - 1;
1726 __scsi_scan_target(&shost->shost_gendev, channel,
1727 order_id, lun, rescan);
1730 __scsi_scan_target(&shost->shost_gendev, channel,
1734 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1735 unsigned int id, u64 lun,
1736 enum scsi_scan_mode rescan)
1738 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1739 "%s: <%u:%u:%llu>\n",
1740 __func__, channel, id, lun));
1742 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1743 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1744 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun)))
1747 mutex_lock(&shost->scan_mutex);
1748 if (!shost->async_scan)
1749 scsi_complete_async_scans();
1751 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1752 if (channel == SCAN_WILD_CARD)
1753 for (channel = 0; channel <= shost->max_channel;
1755 scsi_scan_channel(shost, channel, id, lun,
1758 scsi_scan_channel(shost, channel, id, lun, rescan);
1759 scsi_autopm_put_host(shost);
1761 mutex_unlock(&shost->scan_mutex);
1766 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1768 struct scsi_device *sdev;
1769 shost_for_each_device(sdev, shost) {
1770 /* target removed before the device could be added */
1771 if (sdev->sdev_state == SDEV_DEL)
1773 /* If device is already visible, skip adding it to sysfs */
1774 if (sdev->is_visible)
1776 if (!scsi_host_scan_allowed(shost) ||
1777 scsi_sysfs_add_sdev(sdev) != 0)
1778 __scsi_remove_device(sdev);
1783 * scsi_prep_async_scan - prepare for an async scan
1784 * @shost: the host which will be scanned
1785 * Returns: a cookie to be passed to scsi_finish_async_scan()
1787 * Tells the midlayer this host is going to do an asynchronous scan.
1788 * It reserves the host's position in the scanning list and ensures
1789 * that other asynchronous scans started after this one won't affect the
1790 * ordering of the discovered devices.
1792 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1794 struct async_scan_data *data = NULL;
1795 unsigned long flags;
1797 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1800 mutex_lock(&shost->scan_mutex);
1801 if (shost->async_scan) {
1802 shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__);
1806 data = kmalloc(sizeof(*data), GFP_KERNEL);
1809 data->shost = scsi_host_get(shost);
1812 init_completion(&data->prev_finished);
1814 spin_lock_irqsave(shost->host_lock, flags);
1815 shost->async_scan = 1;
1816 spin_unlock_irqrestore(shost->host_lock, flags);
1817 mutex_unlock(&shost->scan_mutex);
1819 spin_lock(&async_scan_lock);
1820 if (list_empty(&scanning_hosts))
1821 complete(&data->prev_finished);
1822 list_add_tail(&data->list, &scanning_hosts);
1823 spin_unlock(&async_scan_lock);
1828 mutex_unlock(&shost->scan_mutex);
1834 * scsi_finish_async_scan - asynchronous scan has finished
1835 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1837 * All the devices currently attached to this host have been found.
1838 * This function announces all the devices it has found to the rest
1841 static void scsi_finish_async_scan(struct async_scan_data *data)
1843 struct Scsi_Host *shost;
1844 unsigned long flags;
1849 shost = data->shost;
1851 mutex_lock(&shost->scan_mutex);
1853 if (!shost->async_scan) {
1854 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
1856 mutex_unlock(&shost->scan_mutex);
1860 wait_for_completion(&data->prev_finished);
1862 scsi_sysfs_add_devices(shost);
1864 spin_lock_irqsave(shost->host_lock, flags);
1865 shost->async_scan = 0;
1866 spin_unlock_irqrestore(shost->host_lock, flags);
1868 mutex_unlock(&shost->scan_mutex);
1870 spin_lock(&async_scan_lock);
1871 list_del(&data->list);
1872 if (!list_empty(&scanning_hosts)) {
1873 struct async_scan_data *next = list_entry(scanning_hosts.next,
1874 struct async_scan_data, list);
1875 complete(&next->prev_finished);
1877 spin_unlock(&async_scan_lock);
1879 scsi_autopm_put_host(shost);
1880 scsi_host_put(shost);
1884 static void do_scsi_scan_host(struct Scsi_Host *shost)
1886 if (shost->hostt->scan_finished) {
1887 unsigned long start = jiffies;
1888 if (shost->hostt->scan_start)
1889 shost->hostt->scan_start(shost);
1891 while (!shost->hostt->scan_finished(shost, jiffies - start))
1894 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1899 static void do_scan_async(void *_data, async_cookie_t c)
1901 struct async_scan_data *data = _data;
1902 struct Scsi_Host *shost = data->shost;
1904 do_scsi_scan_host(shost);
1905 scsi_finish_async_scan(data);
1909 * scsi_scan_host - scan the given adapter
1910 * @shost: adapter to scan
1912 void scsi_scan_host(struct Scsi_Host *shost)
1914 struct async_scan_data *data;
1916 if (strncmp(scsi_scan_type, "none", 4) == 0 ||
1917 strncmp(scsi_scan_type, "manual", 6) == 0)
1919 if (scsi_autopm_get_host(shost) < 0)
1922 data = scsi_prep_async_scan(shost);
1924 do_scsi_scan_host(shost);
1925 scsi_autopm_put_host(shost);
1929 /* register with the async subsystem so wait_for_device_probe()
1930 * will flush this work
1932 async_schedule(do_scan_async, data);
1934 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
1936 EXPORT_SYMBOL(scsi_scan_host);
1938 void scsi_forget_host(struct Scsi_Host *shost)
1940 struct scsi_device *sdev;
1941 unsigned long flags;
1944 spin_lock_irqsave(shost->host_lock, flags);
1945 list_for_each_entry(sdev, &shost->__devices, siblings) {
1946 if (sdev->sdev_state == SDEV_DEL)
1948 spin_unlock_irqrestore(shost->host_lock, flags);
1949 __scsi_remove_device(sdev);
1952 spin_unlock_irqrestore(shost->host_lock, flags);
1956 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself
1957 * @shost: Host that needs a scsi_device
1959 * Lock status: None assumed.
1961 * Returns: The scsi_device or NULL
1964 * Attach a single scsi_device to the Scsi_Host - this should
1965 * be made to look like a "pseudo-device" that points to the
1968 * Note - this device is not accessible from any high-level
1969 * drivers (including generics), which is probably not
1970 * optimal. We can add hooks later to attach.
1972 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1974 struct scsi_device *sdev = NULL;
1975 struct scsi_target *starget;
1977 mutex_lock(&shost->scan_mutex);
1978 if (!scsi_host_scan_allowed(shost))
1980 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1984 sdev = scsi_alloc_sdev(starget, 0, NULL);
1988 scsi_target_reap(starget);
1989 put_device(&starget->dev);
1991 mutex_unlock(&shost->scan_mutex);
1994 EXPORT_SYMBOL(scsi_get_host_dev);
1997 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself
1998 * @sdev: Host device to be freed
2000 * Lock status: None assumed.
2004 void scsi_free_host_dev(struct scsi_device *sdev)
2006 BUG_ON(sdev->id != sdev->host->this_id);
2008 __scsi_remove_device(sdev);
2010 EXPORT_SYMBOL(scsi_free_host_dev);