4 * Copyright (C) 2000 Eric Youngdale,
5 * Copyright (C) 2002 Patrick Mansfield
7 * The general scanning/probing algorithm is as follows, exceptions are
8 * made to it depending on device specific flags, compilation options, and
9 * global variable (boot or module load time) settings.
11 * A specific LUN is scanned via an INQUIRY command; if the LUN has a
12 * device attached, a scsi_device is allocated and setup for it.
14 * For every id of every channel on the given host:
16 * Scan LUN 0; if the target responds to LUN 0 (even if there is no
17 * device or storage attached to LUN 0):
19 * If LUN 0 has a device attached, allocate and setup a
22 * If target is SCSI-3 or up, issue a REPORT LUN, and scan
23 * all of the LUNs returned by the REPORT LUN; else,
24 * sequentially scan LUNs up until some maximum is reached,
25 * or a LUN is seen that cannot have a device attached to it.
28 #include <linux/module.h>
29 #include <linux/moduleparam.h>
30 #include <linux/init.h>
31 #include <linux/blkdev.h>
32 #include <linux/delay.h>
33 #include <linux/kthread.h>
34 #include <linux/spinlock.h>
35 #include <linux/async.h>
36 #include <linux/slab.h>
37 #include <asm/unaligned.h>
39 #include <scsi/scsi.h>
40 #include <scsi/scsi_cmnd.h>
41 #include <scsi/scsi_device.h>
42 #include <scsi/scsi_driver.h>
43 #include <scsi/scsi_devinfo.h>
44 #include <scsi/scsi_host.h>
45 #include <scsi/scsi_transport.h>
46 #include <scsi/scsi_eh.h>
48 #include "scsi_priv.h"
49 #include "scsi_logging.h"
51 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
52 " SCSI scanning, some SCSI devices might not be configured\n"
57 #define SCSI_TIMEOUT (2*HZ)
58 #define SCSI_REPORT_LUNS_TIMEOUT (30*HZ)
61 * Prefix values for the SCSI id's (stored in sysfs name field)
63 #define SCSI_UID_SER_NUM 'S'
64 #define SCSI_UID_UNKNOWN 'Z'
67 * Return values of some of the scanning functions.
69 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
70 * includes allocation or general failures preventing IO from being sent.
72 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
75 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
78 #define SCSI_SCAN_NO_RESPONSE 0
79 #define SCSI_SCAN_TARGET_PRESENT 1
80 #define SCSI_SCAN_LUN_PRESENT 2
82 static const char *scsi_null_device_strs = "nullnullnullnull";
84 #define MAX_SCSI_LUNS 512
86 static u64 max_scsi_luns = MAX_SCSI_LUNS;
88 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR);
89 MODULE_PARM_DESC(max_luns,
90 "last scsi LUN (should be between 1 and 2^64-1)");
92 #ifdef CONFIG_SCSI_SCAN_ASYNC
93 #define SCSI_SCAN_TYPE_DEFAULT "async"
95 #define SCSI_SCAN_TYPE_DEFAULT "sync"
98 char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT;
100 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
101 MODULE_PARM_DESC(scan, "sync, async or none");
103 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
105 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
106 MODULE_PARM_DESC(inq_timeout,
107 "Timeout (in seconds) waiting for devices to answer INQUIRY."
108 " Default is 20. Some devices may need more; most need less.");
110 /* This lock protects only this list */
111 static DEFINE_SPINLOCK(async_scan_lock);
112 static LIST_HEAD(scanning_hosts);
114 struct async_scan_data {
115 struct list_head list;
116 struct Scsi_Host *shost;
117 struct completion prev_finished;
121 * scsi_complete_async_scans - Wait for asynchronous scans to complete
123 * When this function returns, any host which started scanning before
124 * this function was called will have finished its scan. Hosts which
125 * started scanning after this function was called may or may not have
128 int scsi_complete_async_scans(void)
130 struct async_scan_data *data;
133 if (list_empty(&scanning_hosts))
135 /* If we can't get memory immediately, that's OK. Just
136 * sleep a little. Even if we never get memory, the async
137 * scans will finish eventually.
139 data = kmalloc(sizeof(*data), GFP_KERNEL);
145 init_completion(&data->prev_finished);
147 spin_lock(&async_scan_lock);
148 /* Check that there's still somebody else on the list */
149 if (list_empty(&scanning_hosts))
151 list_add_tail(&data->list, &scanning_hosts);
152 spin_unlock(&async_scan_lock);
154 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
155 wait_for_completion(&data->prev_finished);
157 spin_lock(&async_scan_lock);
158 list_del(&data->list);
159 if (!list_empty(&scanning_hosts)) {
160 struct async_scan_data *next = list_entry(scanning_hosts.next,
161 struct async_scan_data, list);
162 complete(&next->prev_finished);
165 spin_unlock(&async_scan_lock);
172 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
173 * @sdev: scsi device to send command to
174 * @result: area to store the result of the MODE SENSE
177 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
178 * Called for BLIST_KEY devices.
180 static void scsi_unlock_floptical(struct scsi_device *sdev,
181 unsigned char *result)
183 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
185 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n");
186 scsi_cmd[0] = MODE_SENSE;
190 scsi_cmd[4] = 0x2a; /* size */
192 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
193 SCSI_TIMEOUT, 3, NULL);
197 * scsi_alloc_sdev - allocate and setup a scsi_Device
198 * @starget: which target to allocate a &scsi_device for
200 * @hostdata: usually NULL and set by ->slave_alloc instead
203 * Allocate, initialize for io, and return a pointer to a scsi_Device.
204 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
205 * adds scsi_Device to the appropriate list.
208 * scsi_Device pointer, or NULL on failure.
210 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
211 u64 lun, void *hostdata)
213 struct scsi_device *sdev;
214 int display_failure_msg = 1, ret;
215 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
216 extern void scsi_evt_thread(struct work_struct *work);
217 extern void scsi_requeue_run_queue(struct work_struct *work);
219 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
224 sdev->vendor = scsi_null_device_strs;
225 sdev->model = scsi_null_device_strs;
226 sdev->rev = scsi_null_device_strs;
228 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
229 sdev->id = starget->id;
231 sdev->channel = starget->channel;
232 sdev->sdev_state = SDEV_CREATED;
233 INIT_LIST_HEAD(&sdev->siblings);
234 INIT_LIST_HEAD(&sdev->same_target_siblings);
235 INIT_LIST_HEAD(&sdev->cmd_list);
236 INIT_LIST_HEAD(&sdev->starved_entry);
237 INIT_LIST_HEAD(&sdev->event_list);
238 spin_lock_init(&sdev->list_lock);
239 INIT_WORK(&sdev->event_work, scsi_evt_thread);
240 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
242 sdev->sdev_gendev.parent = get_device(&starget->dev);
243 sdev->sdev_target = starget;
245 /* usually NULL and set by ->slave_alloc instead */
246 sdev->hostdata = hostdata;
248 /* if the device needs this changing, it may do so in the
249 * slave_configure function */
250 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
253 * Some low level driver could use device->type
258 * Assume that the device will have handshaking problems,
259 * and then fix this field later if it turns out it
264 if (shost_use_blk_mq(shost))
265 sdev->request_queue = scsi_mq_alloc_queue(sdev);
267 sdev->request_queue = scsi_alloc_queue(sdev);
268 if (!sdev->request_queue) {
269 /* release fn is set up in scsi_sysfs_device_initialise, so
270 * have to free and put manually here */
271 put_device(&starget->dev);
275 WARN_ON_ONCE(!blk_get_queue(sdev->request_queue));
276 sdev->request_queue->queuedata = sdev;
278 if (!shost_use_blk_mq(sdev->host)) {
279 blk_queue_init_tags(sdev->request_queue,
280 sdev->host->cmd_per_lun, shost->bqt,
281 shost->hostt->tag_alloc_policy);
283 scsi_change_queue_depth(sdev, sdev->host->cmd_per_lun ?
284 sdev->host->cmd_per_lun : 1);
286 scsi_sysfs_device_initialize(sdev);
288 if (shost->hostt->slave_alloc) {
289 ret = shost->hostt->slave_alloc(sdev);
292 * if LLDD reports slave not present, don't clutter
293 * console with alloc failure messages
296 display_failure_msg = 0;
297 goto out_device_destroy;
304 __scsi_remove_device(sdev);
306 if (display_failure_msg)
307 printk(ALLOC_FAILURE_MSG, __func__);
311 static void scsi_target_destroy(struct scsi_target *starget)
313 struct device *dev = &starget->dev;
314 struct Scsi_Host *shost = dev_to_shost(dev->parent);
317 BUG_ON(starget->state == STARGET_DEL);
318 starget->state = STARGET_DEL;
319 transport_destroy_device(dev);
320 spin_lock_irqsave(shost->host_lock, flags);
321 if (shost->hostt->target_destroy)
322 shost->hostt->target_destroy(starget);
323 list_del_init(&starget->siblings);
324 spin_unlock_irqrestore(shost->host_lock, flags);
328 static void scsi_target_dev_release(struct device *dev)
330 struct device *parent = dev->parent;
331 struct scsi_target *starget = to_scsi_target(dev);
337 static struct device_type scsi_target_type = {
338 .name = "scsi_target",
339 .release = scsi_target_dev_release,
342 int scsi_is_target_device(const struct device *dev)
344 return dev->type == &scsi_target_type;
346 EXPORT_SYMBOL(scsi_is_target_device);
348 static struct scsi_target *__scsi_find_target(struct device *parent,
349 int channel, uint id)
351 struct scsi_target *starget, *found_starget = NULL;
352 struct Scsi_Host *shost = dev_to_shost(parent);
354 * Search for an existing target for this sdev.
356 list_for_each_entry(starget, &shost->__targets, siblings) {
357 if (starget->id == id &&
358 starget->channel == channel) {
359 found_starget = starget;
364 get_device(&found_starget->dev);
366 return found_starget;
370 * scsi_target_reap_ref_release - remove target from visibility
371 * @kref: the reap_ref in the target being released
373 * Called on last put of reap_ref, which is the indication that no device
374 * under this target is visible anymore, so render the target invisible in
375 * sysfs. Note: we have to be in user context here because the target reaps
376 * should be done in places where the scsi device visibility is being removed.
378 static void scsi_target_reap_ref_release(struct kref *kref)
380 struct scsi_target *starget
381 = container_of(kref, struct scsi_target, reap_ref);
384 * if we get here and the target is still in a CREATED state that
385 * means it was allocated but never made visible (because a scan
386 * turned up no LUNs), so don't call device_del() on it.
388 if ((starget->state != STARGET_CREATED) &&
389 (starget->state != STARGET_CREATED_REMOVE)) {
390 transport_remove_device(&starget->dev);
391 device_del(&starget->dev);
393 scsi_target_destroy(starget);
396 static void scsi_target_reap_ref_put(struct scsi_target *starget)
398 kref_put(&starget->reap_ref, scsi_target_reap_ref_release);
402 * scsi_alloc_target - allocate a new or find an existing target
403 * @parent: parent of the target (need not be a scsi host)
404 * @channel: target channel number (zero if no channels)
405 * @id: target id number
407 * Return an existing target if one exists, provided it hasn't already
408 * gone into STARGET_DEL state, otherwise allocate a new target.
410 * The target is returned with an incremented reference, so the caller
411 * is responsible for both reaping and doing a last put
413 static struct scsi_target *scsi_alloc_target(struct device *parent,
414 int channel, uint id)
416 struct Scsi_Host *shost = dev_to_shost(parent);
417 struct device *dev = NULL;
419 const int size = sizeof(struct scsi_target)
420 + shost->transportt->target_size;
421 struct scsi_target *starget;
422 struct scsi_target *found_target;
425 starget = kzalloc(size, GFP_KERNEL);
427 printk(KERN_ERR "%s: allocation failure\n", __func__);
431 device_initialize(dev);
432 kref_init(&starget->reap_ref);
433 dev->parent = get_device(parent);
434 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
435 dev->bus = &scsi_bus_type;
436 dev->type = &scsi_target_type;
438 starget->channel = channel;
439 starget->can_queue = 0;
440 INIT_LIST_HEAD(&starget->siblings);
441 INIT_LIST_HEAD(&starget->devices);
442 starget->state = STARGET_CREATED;
443 starget->scsi_level = SCSI_2;
444 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
446 spin_lock_irqsave(shost->host_lock, flags);
448 found_target = __scsi_find_target(parent, channel, id);
452 list_add_tail(&starget->siblings, &shost->__targets);
453 spin_unlock_irqrestore(shost->host_lock, flags);
454 /* allocate and add */
455 transport_setup_device(dev);
456 if (shost->hostt->target_alloc) {
457 error = shost->hostt->target_alloc(starget);
460 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
461 /* don't want scsi_target_reap to do the final
462 * put because it will be under the host lock */
463 scsi_target_destroy(starget);
473 * release routine already fired if kref is zero, so if we can still
474 * take the reference, the target must be alive. If we can't, it must
475 * be dying and we need to wait for a new target
477 ref_got = kref_get_unless_zero(&found_target->reap_ref);
479 spin_unlock_irqrestore(shost->host_lock, flags);
485 * Unfortunately, we found a dying target; need to wait until it's
486 * dead before we can get a new one. There is an anomaly here. We
487 * *should* call scsi_target_reap() to balance the kref_get() of the
488 * reap_ref above. However, since the target being released, it's
489 * already invisible and the reap_ref is irrelevant. If we call
490 * scsi_target_reap() we might spuriously do another device_del() on
491 * an already invisible target.
493 put_device(&found_target->dev);
495 * length of time is irrelevant here, we just want to yield the CPU
496 * for a tick to avoid busy waiting for the target to die.
503 * scsi_target_reap - check to see if target is in use and destroy if not
504 * @starget: target to be checked
506 * This is used after removing a LUN or doing a last put of the target
507 * it checks atomically that nothing is using the target and removes
510 void scsi_target_reap(struct scsi_target *starget)
513 * serious problem if this triggers: STARGET_DEL is only set in the if
514 * the reap_ref drops to zero, so we're trying to do another final put
515 * on an already released kref
517 BUG_ON(starget->state == STARGET_DEL);
518 scsi_target_reap_ref_put(starget);
522 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string
523 * @s: INQUIRY result string to sanitize
524 * @len: length of the string
527 * The SCSI spec says that INQUIRY vendor, product, and revision
528 * strings must consist entirely of graphic ASCII characters,
529 * padded on the right with spaces. Since not all devices obey
530 * this rule, we will replace non-graphic or non-ASCII characters
531 * with spaces. Exception: a NUL character is interpreted as a
532 * string terminator, so all the following characters are set to
535 static void sanitize_inquiry_string(unsigned char *s, int len)
539 for (; len > 0; (--len, ++s)) {
542 if (terminated || *s < 0x20 || *s > 0x7e)
548 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
549 * @sdev: scsi_device to probe
550 * @inq_result: area to store the INQUIRY result
551 * @result_len: len of inq_result
552 * @bflags: store any bflags found here
555 * Probe the lun associated with @req using a standard SCSI INQUIRY;
557 * If the INQUIRY is successful, zero is returned and the
558 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
559 * are copied to the scsi_device any flags value is stored in *@bflags.
561 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
562 int result_len, int *bflags)
564 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
565 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
566 int response_len = 0;
567 int pass, count, result;
568 struct scsi_sense_hdr sshdr;
572 /* Perform up to 3 passes. The first pass uses a conservative
573 * transfer length of 36 unless sdev->inquiry_len specifies a
574 * different value. */
575 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
576 try_inquiry_len = first_inquiry_len;
580 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
581 "scsi scan: INQUIRY pass %d length %d\n",
582 pass, try_inquiry_len));
584 /* Each pass gets up to three chances to ignore Unit Attention */
585 for (count = 0; count < 3; ++count) {
588 memset(scsi_cmd, 0, 6);
589 scsi_cmd[0] = INQUIRY;
590 scsi_cmd[4] = (unsigned char) try_inquiry_len;
592 memset(inq_result, 0, try_inquiry_len);
594 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
595 inq_result, try_inquiry_len, &sshdr,
596 HZ / 2 + HZ * scsi_inq_timeout, 3,
599 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
600 "scsi scan: INQUIRY %s with code 0x%x\n",
601 result ? "failed" : "successful", result));
605 * not-ready to ready transition [asc/ascq=0x28/0x0]
606 * or power-on, reset [asc/ascq=0x29/0x0], continue.
607 * INQUIRY should not yield UNIT_ATTENTION
608 * but many buggy devices do so anyway.
610 if ((driver_byte(result) & DRIVER_SENSE) &&
611 scsi_sense_valid(&sshdr)) {
612 if ((sshdr.sense_key == UNIT_ATTENTION) &&
613 ((sshdr.asc == 0x28) ||
614 (sshdr.asc == 0x29)) &&
620 * if nothing was transferred, we try
621 * again. It's a workaround for some USB
624 if (resid == try_inquiry_len)
631 sanitize_inquiry_string(&inq_result[8], 8);
632 sanitize_inquiry_string(&inq_result[16], 16);
633 sanitize_inquiry_string(&inq_result[32], 4);
635 response_len = inq_result[4] + 5;
636 if (response_len > 255)
637 response_len = first_inquiry_len; /* sanity */
640 * Get any flags for this device.
642 * XXX add a bflags to scsi_device, and replace the
643 * corresponding bit fields in scsi_device, so bflags
644 * need not be passed as an argument.
646 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
649 /* When the first pass succeeds we gain information about
650 * what larger transfer lengths might work. */
652 if (BLIST_INQUIRY_36 & *bflags)
653 next_inquiry_len = 36;
654 else if (BLIST_INQUIRY_58 & *bflags)
655 next_inquiry_len = 58;
656 else if (sdev->inquiry_len)
657 next_inquiry_len = sdev->inquiry_len;
659 next_inquiry_len = response_len;
661 /* If more data is available perform the second pass */
662 if (next_inquiry_len > try_inquiry_len) {
663 try_inquiry_len = next_inquiry_len;
669 } else if (pass == 2) {
670 sdev_printk(KERN_INFO, sdev,
671 "scsi scan: %d byte inquiry failed. "
672 "Consider BLIST_INQUIRY_36 for this device\n",
675 /* If this pass failed, the third pass goes back and transfers
676 * the same amount as we successfully got in the first pass. */
677 try_inquiry_len = first_inquiry_len;
682 /* If the last transfer attempt got an error, assume the
683 * peripheral doesn't exist or is dead. */
687 /* Don't report any more data than the device says is valid */
688 sdev->inquiry_len = min(try_inquiry_len, response_len);
691 * XXX Abort if the response length is less than 36? If less than
692 * 32, the lookup of the device flags (above) could be invalid,
693 * and it would be possible to take an incorrect action - we do
694 * not want to hang because of a short INQUIRY. On the flip side,
695 * if the device is spun down or becoming ready (and so it gives a
696 * short INQUIRY), an abort here prevents any further use of the
697 * device, including spin up.
699 * On the whole, the best approach seems to be to assume the first
700 * 36 bytes are valid no matter what the device says. That's
701 * better than copying < 36 bytes to the inquiry-result buffer
702 * and displaying garbage for the Vendor, Product, or Revision
705 if (sdev->inquiry_len < 36) {
706 if (!sdev->host->short_inquiry) {
707 shost_printk(KERN_INFO, sdev->host,
708 "scsi scan: INQUIRY result too short (%d),"
709 " using 36\n", sdev->inquiry_len);
710 sdev->host->short_inquiry = 1;
712 sdev->inquiry_len = 36;
716 * Related to the above issue:
718 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
719 * and if not ready, sent a START_STOP to start (maybe spin up) and
720 * then send the INQUIRY again, since the INQUIRY can change after
721 * a device is initialized.
723 * Ideally, start a device if explicitly asked to do so. This
724 * assumes that a device is spun up on power on, spun down on
725 * request, and then spun up on request.
729 * The scanning code needs to know the scsi_level, even if no
730 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
731 * non-zero LUNs can be scanned.
733 sdev->scsi_level = inq_result[2] & 0x07;
734 if (sdev->scsi_level >= 2 ||
735 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
737 sdev->sdev_target->scsi_level = sdev->scsi_level;
740 * If SCSI-2 or lower, and if the transport requires it,
741 * store the LUN value in CDB[1].
743 sdev->lun_in_cdb = 0;
744 if (sdev->scsi_level <= SCSI_2 &&
745 sdev->scsi_level != SCSI_UNKNOWN &&
746 !sdev->host->no_scsi2_lun_in_cdb)
747 sdev->lun_in_cdb = 1;
753 * scsi_add_lun - allocate and fully initialze a scsi_device
754 * @sdev: holds information to be stored in the new scsi_device
755 * @inq_result: holds the result of a previous INQUIRY to the LUN
756 * @bflags: black/white list flag
757 * @async: 1 if this device is being scanned asynchronously
760 * Initialize the scsi_device @sdev. Optionally set fields based
761 * on values in *@bflags.
764 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
765 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
767 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
768 int *bflags, int async)
773 * XXX do not save the inquiry, since it can change underneath us,
774 * save just vendor/model/rev.
776 * Rather than save it and have an ioctl that retrieves the saved
777 * value, have an ioctl that executes the same INQUIRY code used
778 * in scsi_probe_lun, let user level programs doing INQUIRY
779 * scanning run at their own risk, or supply a user level program
780 * that can correctly scan.
784 * Copy at least 36 bytes of INQUIRY data, so that we don't
785 * dereference unallocated memory when accessing the Vendor,
786 * Product, and Revision strings. Badly behaved devices may set
787 * the INQUIRY Additional Length byte to a small value, indicating
788 * these strings are invalid, but often they contain plausible data
789 * nonetheless. It doesn't matter if the device sent < 36 bytes
790 * total, since scsi_probe_lun() initializes inq_result with 0s.
792 sdev->inquiry = kmemdup(inq_result,
793 max_t(size_t, sdev->inquiry_len, 36),
795 if (sdev->inquiry == NULL)
796 return SCSI_SCAN_NO_RESPONSE;
798 sdev->vendor = (char *) (sdev->inquiry + 8);
799 sdev->model = (char *) (sdev->inquiry + 16);
800 sdev->rev = (char *) (sdev->inquiry + 32);
802 if (strncmp(sdev->vendor, "ATA ", 8) == 0) {
804 * sata emulation layer device. This is a hack to work around
805 * the SATL power management specifications which state that
806 * when the SATL detects the device has gone into standby
807 * mode, it shall respond with NOT READY.
809 sdev->allow_restart = 1;
812 if (*bflags & BLIST_ISROM) {
813 sdev->type = TYPE_ROM;
816 sdev->type = (inq_result[0] & 0x1f);
817 sdev->removable = (inq_result[1] & 0x80) >> 7;
820 * some devices may respond with wrong type for
821 * well-known logical units. Force well-known type
822 * to enumerate them correctly.
824 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) {
825 sdev_printk(KERN_WARNING, sdev,
826 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n",
827 __func__, sdev->type, (unsigned int)sdev->lun);
828 sdev->type = TYPE_WLUN;
833 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
834 /* RBC and MMC devices can return SCSI-3 compliance and yet
835 * still not support REPORT LUNS, so make them act as
836 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
837 * specifically set */
838 if ((*bflags & BLIST_REPORTLUN2) == 0)
839 *bflags |= BLIST_NOREPORTLUN;
843 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
844 * spec says: The device server is capable of supporting the
845 * specified peripheral device type on this logical unit. However,
846 * the physical device is not currently connected to this logical
849 * The above is vague, as it implies that we could treat 001 and
850 * 011 the same. Stay compatible with previous code, and create a
851 * scsi_device for a PQ of 1
853 * Don't set the device offline here; rather let the upper
854 * level drivers eval the PQ to decide whether they should
855 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
858 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
859 sdev->lockable = sdev->removable;
860 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
862 if (sdev->scsi_level >= SCSI_3 ||
863 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
865 if (inq_result[7] & 0x60)
867 if (inq_result[7] & 0x10)
870 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
871 "ANSI: %d%s\n", scsi_device_type(sdev->type),
872 sdev->vendor, sdev->model, sdev->rev,
873 sdev->inq_periph_qual, inq_result[2] & 0x07,
874 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
876 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
877 !(*bflags & BLIST_NOTQ)) {
878 sdev->tagged_supported = 1;
879 sdev->simple_tags = 1;
883 * Some devices (Texel CD ROM drives) have handshaking problems
884 * when used with the Seagate controllers. borken is initialized
885 * to 1, and then set it to 0 here.
887 if ((*bflags & BLIST_BORKEN) == 0)
890 if (*bflags & BLIST_NO_ULD_ATTACH)
891 sdev->no_uld_attach = 1;
894 * Apparently some really broken devices (contrary to the SCSI
895 * standards) need to be selected without asserting ATN
897 if (*bflags & BLIST_SELECT_NO_ATN)
898 sdev->select_no_atn = 1;
901 * Maximum 512 sector transfer length
902 * broken RA4x00 Compaq Disk Array
904 if (*bflags & BLIST_MAX_512)
905 blk_queue_max_hw_sectors(sdev->request_queue, 512);
907 * Max 1024 sector transfer length for targets that report incorrect
908 * max/optimal lengths and relied on the old block layer safe default
910 else if (*bflags & BLIST_MAX_1024)
911 blk_queue_max_hw_sectors(sdev->request_queue, 1024);
914 * Some devices may not want to have a start command automatically
915 * issued when a device is added.
917 if (*bflags & BLIST_NOSTARTONADD)
918 sdev->no_start_on_add = 1;
920 if (*bflags & BLIST_SINGLELUN)
921 scsi_target(sdev)->single_lun = 1;
923 sdev->use_10_for_rw = 1;
925 if (*bflags & BLIST_MS_SKIP_PAGE_08)
926 sdev->skip_ms_page_8 = 1;
928 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
929 sdev->skip_ms_page_3f = 1;
931 if (*bflags & BLIST_USE_10_BYTE_MS)
932 sdev->use_10_for_ms = 1;
934 /* some devices don't like REPORT SUPPORTED OPERATION CODES
935 * and will simply timeout causing sd_mod init to take a very
937 if (*bflags & BLIST_NO_RSOC)
938 sdev->no_report_opcodes = 1;
940 /* set the device running here so that slave configure
942 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
944 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
947 sdev_printk(KERN_ERR, sdev,
948 "in wrong state %s to complete scan\n",
949 scsi_device_state_name(sdev->sdev_state));
950 return SCSI_SCAN_NO_RESPONSE;
954 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
955 sdev->use_192_bytes_for_3f = 1;
957 if (*bflags & BLIST_NOT_LOCKABLE)
960 if (*bflags & BLIST_RETRY_HWERROR)
961 sdev->retry_hwerror = 1;
963 if (*bflags & BLIST_NO_DIF)
966 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
968 if (*bflags & BLIST_TRY_VPD_PAGES)
969 sdev->try_vpd_pages = 1;
970 else if (*bflags & BLIST_SKIP_VPD_PAGES)
971 sdev->skip_vpd_pages = 1;
973 transport_configure_device(&sdev->sdev_gendev);
975 if (sdev->host->hostt->slave_configure) {
976 ret = sdev->host->hostt->slave_configure(sdev);
979 * if LLDD reports slave not present, don't clutter
980 * console with alloc failure messages
983 sdev_printk(KERN_ERR, sdev,
984 "failed to configure device\n");
986 return SCSI_SCAN_NO_RESPONSE;
990 if (sdev->scsi_level >= SCSI_3)
991 scsi_attach_vpd(sdev);
993 sdev->max_queue_depth = sdev->queue_depth;
996 * Ok, the device is now all set up, we can
997 * register it and tell the rest of the kernel
1000 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
1001 return SCSI_SCAN_NO_RESPONSE;
1003 return SCSI_SCAN_LUN_PRESENT;
1006 #ifdef CONFIG_SCSI_LOGGING
1008 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
1009 * @buf: Output buffer with at least end-first+1 bytes of space
1010 * @inq: Inquiry buffer (input)
1011 * @first: Offset of string into inq
1012 * @end: Index after last character in inq
1014 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
1015 unsigned first, unsigned end)
1017 unsigned term = 0, idx;
1019 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
1020 if (inq[idx+first] > ' ') {
1021 buf[idx] = inq[idx+first];
1033 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
1034 * @starget: pointer to target device structure
1035 * @lun: LUN of target device
1036 * @bflagsp: store bflags here if not NULL
1037 * @sdevp: probe the LUN corresponding to this scsi_device
1038 * @rescan: if nonzero skip some code only needed on first scan
1039 * @hostdata: passed to scsi_alloc_sdev()
1042 * Call scsi_probe_lun, if a LUN with an attached device is found,
1043 * allocate and set it up by calling scsi_add_lun.
1046 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1047 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1048 * attached at the LUN
1049 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1051 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1052 u64 lun, int *bflagsp,
1053 struct scsi_device **sdevp, int rescan,
1056 struct scsi_device *sdev;
1057 unsigned char *result;
1058 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1059 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1062 * The rescan flag is used as an optimization, the first scan of a
1063 * host adapter calls into here with rescan == 0.
1065 sdev = scsi_device_lookup_by_target(starget, lun);
1067 if (rescan || !scsi_device_created(sdev)) {
1068 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1069 "scsi scan: device exists on %s\n",
1070 dev_name(&sdev->sdev_gendev)));
1074 scsi_device_put(sdev);
1077 *bflagsp = scsi_get_device_flags(sdev,
1080 return SCSI_SCAN_LUN_PRESENT;
1082 scsi_device_put(sdev);
1084 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1088 result = kmalloc(result_len, GFP_ATOMIC |
1089 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
1093 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1094 goto out_free_result;
1099 * result contains valid SCSI INQUIRY data.
1101 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
1103 * For a Peripheral qualifier 3 (011b), the SCSI
1104 * spec says: The device server is not capable of
1105 * supporting a physical device on this logical
1108 * For disks, this implies that there is no
1109 * logical disk configured at sdev->lun, but there
1110 * is a target id responding.
1112 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1113 " peripheral qualifier of 3, device not"
1116 SCSI_LOG_SCAN_BUS(1, {
1117 unsigned char vend[9];
1118 unsigned char mod[17];
1120 sdev_printk(KERN_INFO, sdev,
1121 "scsi scan: consider passing scsi_mod."
1122 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1123 scsi_inq_str(vend, result, 8, 16),
1124 scsi_inq_str(mod, result, 16, 32));
1129 res = SCSI_SCAN_TARGET_PRESENT;
1130 goto out_free_result;
1134 * Some targets may set slight variations of PQ and PDT to signal
1135 * that no LUN is present, so don't add sdev in these cases.
1136 * Two specific examples are:
1137 * 1) NetApp targets: return PQ=1, PDT=0x1f
1138 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1139 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1142 * 1) SCSI SPC-3, pp. 145-146
1143 * PQ=1: "A peripheral device having the specified peripheral
1144 * device type is not connected to this logical unit. However, the
1145 * device server is capable of supporting the specified peripheral
1146 * device type on this logical unit."
1147 * PDT=0x1f: "Unknown or no device type"
1148 * 2) USB UFI 1.0, p. 20
1149 * PDT=00h Direct-access device (floppy)
1150 * PDT=1Fh none (no FDD connected to the requested logical unit)
1152 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1153 (result[0] & 0x1f) == 0x1f &&
1154 !scsi_is_wlun(lun)) {
1155 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1156 "scsi scan: peripheral device type"
1157 " of 31, no device added\n"));
1158 res = SCSI_SCAN_TARGET_PRESENT;
1159 goto out_free_result;
1162 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1163 if (res == SCSI_SCAN_LUN_PRESENT) {
1164 if (bflags & BLIST_KEY) {
1166 scsi_unlock_floptical(sdev, result);
1173 if (res == SCSI_SCAN_LUN_PRESENT) {
1175 if (scsi_device_get(sdev) == 0) {
1178 __scsi_remove_device(sdev);
1179 res = SCSI_SCAN_NO_RESPONSE;
1183 __scsi_remove_device(sdev);
1189 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1190 * @starget: pointer to target structure to scan
1191 * @bflags: black/white list flag for LUN 0
1192 * @scsi_level: Which version of the standard does this device adhere to
1193 * @rescan: passed to scsi_probe_add_lun()
1196 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1197 * scanned) to some maximum lun until a LUN is found with no device
1198 * attached. Use the bflags to figure out any oddities.
1200 * Modifies sdevscan->lun.
1202 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1203 int bflags, int scsi_level, int rescan)
1206 u64 sparse_lun, lun;
1207 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1209 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget,
1210 "scsi scan: Sequential scan\n"));
1212 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1214 * If this device is known to support sparse multiple units,
1215 * override the other settings, and scan all of them. Normally,
1216 * SCSI-3 devices should be scanned via the REPORT LUNS.
1218 if (bflags & BLIST_SPARSELUN) {
1219 max_dev_lun = shost->max_lun;
1225 * If less than SCSI_1_CCS, and no special lun scanning, stop
1226 * scanning; this matches 2.4 behaviour, but could just be a bug
1227 * (to continue scanning a SCSI_1_CCS device).
1229 * This test is broken. We might not have any device on lun0 for
1230 * a sparselun device, and if that's the case then how would we
1231 * know the real scsi_level, eh? It might make sense to just not
1232 * scan any SCSI_1 device for non-0 luns, but that check would best
1233 * go into scsi_alloc_sdev() and just have it return null when asked
1234 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1236 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1237 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1242 * If this device is known to support multiple units, override
1243 * the other settings, and scan all of them.
1245 if (bflags & BLIST_FORCELUN)
1246 max_dev_lun = shost->max_lun;
1248 * REGAL CDC-4X: avoid hang after LUN 4
1250 if (bflags & BLIST_MAX5LUN)
1251 max_dev_lun = min(5U, max_dev_lun);
1253 * Do not scan SCSI-2 or lower device past LUN 7, unless
1256 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1257 max_dev_lun = min(8U, max_dev_lun);
1260 * Stop scanning at 255 unless BLIST_SCSI3LUN
1262 if (!(bflags & BLIST_SCSI3LUN))
1263 max_dev_lun = min(256U, max_dev_lun);
1266 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1267 * until we reach the max, or no LUN is found and we are not
1270 for (lun = 1; lun < max_dev_lun; ++lun)
1271 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1272 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1278 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1279 * @starget: which target
1280 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1281 * @rescan: nonzero if we can skip code only needed on first scan
1284 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1285 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1287 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1288 * LUNs even if it's older than SCSI-3.
1289 * If BLIST_NOREPORTLUN is set, return 1 always.
1290 * If BLIST_NOLUN is set, return 0 always.
1291 * If starget->no_report_luns is set, return 1 always.
1294 * 0: scan completed (or no memory, so further scanning is futile)
1295 * 1: could not scan with REPORT LUN
1297 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1301 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1302 unsigned int length;
1304 unsigned int num_luns;
1305 unsigned int retries;
1307 struct scsi_lun *lunp, *lun_data;
1308 struct scsi_sense_hdr sshdr;
1309 struct scsi_device *sdev;
1310 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1314 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1315 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1316 * support more than 8 LUNs.
1317 * Don't attempt if the target doesn't support REPORT LUNS.
1319 if (bflags & BLIST_NOREPORTLUN)
1321 if (starget->scsi_level < SCSI_2 &&
1322 starget->scsi_level != SCSI_UNKNOWN)
1324 if (starget->scsi_level < SCSI_3 &&
1325 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1327 if (bflags & BLIST_NOLUN)
1329 if (starget->no_report_luns)
1332 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1333 sdev = scsi_alloc_sdev(starget, 0, NULL);
1336 if (scsi_device_get(sdev)) {
1337 __scsi_remove_device(sdev);
1342 sprintf(devname, "host %d channel %d id %d",
1343 shost->host_no, sdev->channel, sdev->id);
1346 * Allocate enough to hold the header (the same size as one scsi_lun)
1347 * plus the number of luns we are requesting. 511 was the default
1348 * value of the now removed max_report_luns parameter.
1350 length = (511 + 1) * sizeof(struct scsi_lun);
1352 lun_data = kmalloc(length, GFP_KERNEL |
1353 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1355 printk(ALLOC_FAILURE_MSG, __func__);
1359 scsi_cmd[0] = REPORT_LUNS;
1362 * bytes 1 - 5: reserved, set to zero.
1364 memset(&scsi_cmd[1], 0, 5);
1367 * bytes 6 - 9: length of the command.
1369 put_unaligned_be32(length, &scsi_cmd[6]);
1371 scsi_cmd[10] = 0; /* reserved */
1372 scsi_cmd[11] = 0; /* control */
1375 * We can get a UNIT ATTENTION, for example a power on/reset, so
1376 * retry a few times (like sd.c does for TEST UNIT READY).
1377 * Experience shows some combinations of adapter/devices get at
1378 * least two power on/resets.
1380 * Illegal requests (for devices that do not support REPORT LUNS)
1381 * should come through as a check condition, and will not generate
1384 for (retries = 0; retries < 3; retries++) {
1385 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1386 "scsi scan: Sending REPORT LUNS to (try %d)\n",
1389 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1390 lun_data, length, &sshdr,
1391 SCSI_REPORT_LUNS_TIMEOUT, 3, NULL);
1393 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1394 "scsi scan: REPORT LUNS"
1395 " %s (try %d) result 0x%x\n",
1396 result ? "failed" : "successful",
1400 else if (scsi_sense_valid(&sshdr)) {
1401 if (sshdr.sense_key != UNIT_ATTENTION)
1408 * The device probably does not support a REPORT LUN command
1415 * Get the length from the first four bytes of lun_data.
1417 if (get_unaligned_be32(lun_data->scsi_lun) +
1418 sizeof(struct scsi_lun) > length) {
1419 length = get_unaligned_be32(lun_data->scsi_lun) +
1420 sizeof(struct scsi_lun);
1424 length = get_unaligned_be32(lun_data->scsi_lun);
1426 num_luns = (length / sizeof(struct scsi_lun));
1428 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1429 "scsi scan: REPORT LUN scan\n"));
1432 * Scan the luns in lun_data. The entry at offset 0 is really
1433 * the header, so start at 1 and go up to and including num_luns.
1435 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1436 lun = scsilun_to_int(lunp);
1438 if (lun > sdev->host->max_lun) {
1439 sdev_printk(KERN_WARNING, sdev,
1440 "lun%llu has a LUN larger than"
1441 " allowed by the host adapter\n", lun);
1445 res = scsi_probe_and_add_lun(starget,
1446 lun, NULL, NULL, rescan, NULL);
1447 if (res == SCSI_SCAN_NO_RESPONSE) {
1449 * Got some results, but now none, abort.
1451 sdev_printk(KERN_ERR, sdev,
1452 "Unexpected response"
1453 " from lun %llu while scanning, scan"
1454 " aborted\n", (unsigned long long)lun);
1463 if (scsi_device_created(sdev))
1465 * the sdev we used didn't appear in the report luns scan
1467 __scsi_remove_device(sdev);
1468 scsi_device_put(sdev);
1472 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1473 uint id, u64 lun, void *hostdata)
1475 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1476 struct device *parent = &shost->shost_gendev;
1477 struct scsi_target *starget;
1479 if (strncmp(scsi_scan_type, "none", 4) == 0)
1480 return ERR_PTR(-ENODEV);
1482 starget = scsi_alloc_target(parent, channel, id);
1484 return ERR_PTR(-ENOMEM);
1485 scsi_autopm_get_target(starget);
1487 mutex_lock(&shost->scan_mutex);
1488 if (!shost->async_scan)
1489 scsi_complete_async_scans();
1491 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1492 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1493 scsi_autopm_put_host(shost);
1495 mutex_unlock(&shost->scan_mutex);
1496 scsi_autopm_put_target(starget);
1498 * paired with scsi_alloc_target(). Target will be destroyed unless
1499 * scsi_probe_and_add_lun made an underlying device visible
1501 scsi_target_reap(starget);
1502 put_device(&starget->dev);
1506 EXPORT_SYMBOL(__scsi_add_device);
1508 int scsi_add_device(struct Scsi_Host *host, uint channel,
1509 uint target, u64 lun)
1511 struct scsi_device *sdev =
1512 __scsi_add_device(host, channel, target, lun, NULL);
1514 return PTR_ERR(sdev);
1516 scsi_device_put(sdev);
1519 EXPORT_SYMBOL(scsi_add_device);
1521 void scsi_rescan_device(struct device *dev)
1524 if (dev->driver && try_module_get(dev->driver->owner)) {
1525 struct scsi_driver *drv = to_scsi_driver(dev->driver);
1529 module_put(dev->driver->owner);
1533 EXPORT_SYMBOL(scsi_rescan_device);
1535 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1536 unsigned int id, u64 lun, int rescan)
1538 struct Scsi_Host *shost = dev_to_shost(parent);
1541 struct scsi_target *starget;
1543 if (shost->this_id == id)
1545 * Don't scan the host adapter
1549 starget = scsi_alloc_target(parent, channel, id);
1552 scsi_autopm_get_target(starget);
1554 if (lun != SCAN_WILD_CARD) {
1556 * Scan for a specific host/chan/id/lun.
1558 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1563 * Scan LUN 0, if there is some response, scan further. Ideally, we
1564 * would not configure LUN 0 until all LUNs are scanned.
1566 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1567 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1568 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1570 * The REPORT LUN did not scan the target,
1571 * do a sequential scan.
1573 scsi_sequential_lun_scan(starget, bflags,
1574 starget->scsi_level, rescan);
1578 scsi_autopm_put_target(starget);
1580 * paired with scsi_alloc_target(): determine if the target has
1581 * any children at all and if not, nuke it
1583 scsi_target_reap(starget);
1585 put_device(&starget->dev);
1589 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1590 * @parent: host to scan
1591 * @channel: channel to scan
1592 * @id: target id to scan
1593 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1594 * @rescan: passed to LUN scanning routines
1597 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1598 * and possibly all LUNs on the target id.
1600 * First try a REPORT LUN scan, if that does not scan the target, do a
1601 * sequential scan of LUNs on the target id.
1603 void scsi_scan_target(struct device *parent, unsigned int channel,
1604 unsigned int id, u64 lun, int rescan)
1606 struct Scsi_Host *shost = dev_to_shost(parent);
1608 if (strncmp(scsi_scan_type, "none", 4) == 0)
1611 mutex_lock(&shost->scan_mutex);
1612 if (!shost->async_scan)
1613 scsi_complete_async_scans();
1615 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1616 __scsi_scan_target(parent, channel, id, lun, rescan);
1617 scsi_autopm_put_host(shost);
1619 mutex_unlock(&shost->scan_mutex);
1621 EXPORT_SYMBOL(scsi_scan_target);
1623 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1624 unsigned int id, u64 lun, int rescan)
1628 if (id == SCAN_WILD_CARD)
1629 for (id = 0; id < shost->max_id; ++id) {
1631 * XXX adapter drivers when possible (FCP, iSCSI)
1632 * could modify max_id to match the current max,
1633 * not the absolute max.
1635 * XXX add a shost id iterator, so for example,
1636 * the FC ID can be the same as a target id
1637 * without a huge overhead of sparse id's.
1639 if (shost->reverse_ordering)
1641 * Scan from high to low id.
1643 order_id = shost->max_id - id - 1;
1646 __scsi_scan_target(&shost->shost_gendev, channel,
1647 order_id, lun, rescan);
1650 __scsi_scan_target(&shost->shost_gendev, channel,
1654 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1655 unsigned int id, u64 lun, int rescan)
1657 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1658 "%s: <%u:%u:%llu>\n",
1659 __func__, channel, id, lun));
1661 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1662 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1663 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun)))
1666 mutex_lock(&shost->scan_mutex);
1667 if (!shost->async_scan)
1668 scsi_complete_async_scans();
1670 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1671 if (channel == SCAN_WILD_CARD)
1672 for (channel = 0; channel <= shost->max_channel;
1674 scsi_scan_channel(shost, channel, id, lun,
1677 scsi_scan_channel(shost, channel, id, lun, rescan);
1678 scsi_autopm_put_host(shost);
1680 mutex_unlock(&shost->scan_mutex);
1685 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1687 struct scsi_device *sdev;
1688 shost_for_each_device(sdev, shost) {
1689 /* target removed before the device could be added */
1690 if (sdev->sdev_state == SDEV_DEL)
1692 /* If device is already visible, skip adding it to sysfs */
1693 if (sdev->is_visible)
1695 if (!scsi_host_scan_allowed(shost) ||
1696 scsi_sysfs_add_sdev(sdev) != 0)
1697 __scsi_remove_device(sdev);
1702 * scsi_prep_async_scan - prepare for an async scan
1703 * @shost: the host which will be scanned
1704 * Returns: a cookie to be passed to scsi_finish_async_scan()
1706 * Tells the midlayer this host is going to do an asynchronous scan.
1707 * It reserves the host's position in the scanning list and ensures
1708 * that other asynchronous scans started after this one won't affect the
1709 * ordering of the discovered devices.
1711 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1713 struct async_scan_data *data;
1714 unsigned long flags;
1716 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1719 if (shost->async_scan) {
1720 shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__);
1724 data = kmalloc(sizeof(*data), GFP_KERNEL);
1727 data->shost = scsi_host_get(shost);
1730 init_completion(&data->prev_finished);
1732 mutex_lock(&shost->scan_mutex);
1733 spin_lock_irqsave(shost->host_lock, flags);
1734 shost->async_scan = 1;
1735 spin_unlock_irqrestore(shost->host_lock, flags);
1736 mutex_unlock(&shost->scan_mutex);
1738 spin_lock(&async_scan_lock);
1739 if (list_empty(&scanning_hosts))
1740 complete(&data->prev_finished);
1741 list_add_tail(&data->list, &scanning_hosts);
1742 spin_unlock(&async_scan_lock);
1752 * scsi_finish_async_scan - asynchronous scan has finished
1753 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1755 * All the devices currently attached to this host have been found.
1756 * This function announces all the devices it has found to the rest
1759 static void scsi_finish_async_scan(struct async_scan_data *data)
1761 struct Scsi_Host *shost;
1762 unsigned long flags;
1767 shost = data->shost;
1769 mutex_lock(&shost->scan_mutex);
1771 if (!shost->async_scan) {
1772 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
1774 mutex_unlock(&shost->scan_mutex);
1778 wait_for_completion(&data->prev_finished);
1780 scsi_sysfs_add_devices(shost);
1782 spin_lock_irqsave(shost->host_lock, flags);
1783 shost->async_scan = 0;
1784 spin_unlock_irqrestore(shost->host_lock, flags);
1786 mutex_unlock(&shost->scan_mutex);
1788 spin_lock(&async_scan_lock);
1789 list_del(&data->list);
1790 if (!list_empty(&scanning_hosts)) {
1791 struct async_scan_data *next = list_entry(scanning_hosts.next,
1792 struct async_scan_data, list);
1793 complete(&next->prev_finished);
1795 spin_unlock(&async_scan_lock);
1797 scsi_autopm_put_host(shost);
1798 scsi_host_put(shost);
1802 static void do_scsi_scan_host(struct Scsi_Host *shost)
1804 if (shost->hostt->scan_finished) {
1805 unsigned long start = jiffies;
1806 if (shost->hostt->scan_start)
1807 shost->hostt->scan_start(shost);
1809 while (!shost->hostt->scan_finished(shost, jiffies - start))
1812 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1817 static void do_scan_async(void *_data, async_cookie_t c)
1819 struct async_scan_data *data = _data;
1820 struct Scsi_Host *shost = data->shost;
1822 do_scsi_scan_host(shost);
1823 scsi_finish_async_scan(data);
1827 * scsi_scan_host - scan the given adapter
1828 * @shost: adapter to scan
1830 void scsi_scan_host(struct Scsi_Host *shost)
1832 struct async_scan_data *data;
1834 if (strncmp(scsi_scan_type, "none", 4) == 0)
1836 if (scsi_autopm_get_host(shost) < 0)
1839 data = scsi_prep_async_scan(shost);
1841 do_scsi_scan_host(shost);
1842 scsi_autopm_put_host(shost);
1846 /* register with the async subsystem so wait_for_device_probe()
1847 * will flush this work
1849 async_schedule(do_scan_async, data);
1851 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
1853 EXPORT_SYMBOL(scsi_scan_host);
1855 void scsi_forget_host(struct Scsi_Host *shost)
1857 struct scsi_device *sdev;
1858 unsigned long flags;
1861 spin_lock_irqsave(shost->host_lock, flags);
1862 list_for_each_entry(sdev, &shost->__devices, siblings) {
1863 if (sdev->sdev_state == SDEV_DEL)
1865 spin_unlock_irqrestore(shost->host_lock, flags);
1866 __scsi_remove_device(sdev);
1869 spin_unlock_irqrestore(shost->host_lock, flags);
1873 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself
1874 * @shost: Host that needs a scsi_device
1876 * Lock status: None assumed.
1878 * Returns: The scsi_device or NULL
1881 * Attach a single scsi_device to the Scsi_Host - this should
1882 * be made to look like a "pseudo-device" that points to the
1885 * Note - this device is not accessible from any high-level
1886 * drivers (including generics), which is probably not
1887 * optimal. We can add hooks later to attach.
1889 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1891 struct scsi_device *sdev = NULL;
1892 struct scsi_target *starget;
1894 mutex_lock(&shost->scan_mutex);
1895 if (!scsi_host_scan_allowed(shost))
1897 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1901 sdev = scsi_alloc_sdev(starget, 0, NULL);
1905 scsi_target_reap(starget);
1906 put_device(&starget->dev);
1908 mutex_unlock(&shost->scan_mutex);
1911 EXPORT_SYMBOL(scsi_get_host_dev);
1914 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself
1915 * @sdev: Host device to be freed
1917 * Lock status: None assumed.
1921 void scsi_free_host_dev(struct scsi_device *sdev)
1923 BUG_ON(sdev->id != sdev->host->this_id);
1925 __scsi_remove_device(sdev);
1927 EXPORT_SYMBOL(scsi_free_host_dev);