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)
60 * Prefix values for the SCSI id's (stored in sysfs name field)
62 #define SCSI_UID_SER_NUM 'S'
63 #define SCSI_UID_UNKNOWN 'Z'
66 * Return values of some of the scanning functions.
68 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
69 * includes allocation or general failures preventing IO from being sent.
71 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
74 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
77 #define SCSI_SCAN_NO_RESPONSE 0
78 #define SCSI_SCAN_TARGET_PRESENT 1
79 #define SCSI_SCAN_LUN_PRESENT 2
81 static const char *scsi_null_device_strs = "nullnullnullnull";
83 #define MAX_SCSI_LUNS 512
85 static u64 max_scsi_luns = MAX_SCSI_LUNS;
87 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR);
88 MODULE_PARM_DESC(max_luns,
89 "last scsi LUN (should be between 1 and 2^64-1)");
91 #ifdef CONFIG_SCSI_SCAN_ASYNC
92 #define SCSI_SCAN_TYPE_DEFAULT "async"
94 #define SCSI_SCAN_TYPE_DEFAULT "sync"
97 char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT;
99 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
100 MODULE_PARM_DESC(scan, "sync, async or none");
102 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
104 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
105 MODULE_PARM_DESC(inq_timeout,
106 "Timeout (in seconds) waiting for devices to answer INQUIRY."
107 " Default is 20. Some devices may need more; most need less.");
109 /* This lock protects only this list */
110 static DEFINE_SPINLOCK(async_scan_lock);
111 static LIST_HEAD(scanning_hosts);
113 struct async_scan_data {
114 struct list_head list;
115 struct Scsi_Host *shost;
116 struct completion prev_finished;
120 * scsi_complete_async_scans - Wait for asynchronous scans to complete
122 * When this function returns, any host which started scanning before
123 * this function was called will have finished its scan. Hosts which
124 * started scanning after this function was called may or may not have
127 int scsi_complete_async_scans(void)
129 struct async_scan_data *data;
132 if (list_empty(&scanning_hosts))
134 /* If we can't get memory immediately, that's OK. Just
135 * sleep a little. Even if we never get memory, the async
136 * scans will finish eventually.
138 data = kmalloc(sizeof(*data), GFP_KERNEL);
144 init_completion(&data->prev_finished);
146 spin_lock(&async_scan_lock);
147 /* Check that there's still somebody else on the list */
148 if (list_empty(&scanning_hosts))
150 list_add_tail(&data->list, &scanning_hosts);
151 spin_unlock(&async_scan_lock);
153 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
154 wait_for_completion(&data->prev_finished);
156 spin_lock(&async_scan_lock);
157 list_del(&data->list);
158 if (!list_empty(&scanning_hosts)) {
159 struct async_scan_data *next = list_entry(scanning_hosts.next,
160 struct async_scan_data, list);
161 complete(&next->prev_finished);
164 spin_unlock(&async_scan_lock);
171 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
172 * @sdev: scsi device to send command to
173 * @result: area to store the result of the MODE SENSE
176 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
177 * Called for BLIST_KEY devices.
179 static void scsi_unlock_floptical(struct scsi_device *sdev,
180 unsigned char *result)
182 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
184 sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n");
185 scsi_cmd[0] = MODE_SENSE;
189 scsi_cmd[4] = 0x2a; /* size */
191 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
192 SCSI_TIMEOUT, 3, NULL);
196 * scsi_alloc_sdev - allocate and setup a scsi_Device
197 * @starget: which target to allocate a &scsi_device for
199 * @hostdata: usually NULL and set by ->slave_alloc instead
202 * Allocate, initialize for io, and return a pointer to a scsi_Device.
203 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
204 * adds scsi_Device to the appropriate list.
207 * scsi_Device pointer, or NULL on failure.
209 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
210 u64 lun, void *hostdata)
212 struct scsi_device *sdev;
213 int display_failure_msg = 1, ret;
214 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
215 extern void scsi_evt_thread(struct work_struct *work);
216 extern void scsi_requeue_run_queue(struct work_struct *work);
218 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
223 sdev->vendor = scsi_null_device_strs;
224 sdev->model = scsi_null_device_strs;
225 sdev->rev = scsi_null_device_strs;
227 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
228 sdev->id = starget->id;
230 sdev->channel = starget->channel;
231 sdev->sdev_state = SDEV_CREATED;
232 INIT_LIST_HEAD(&sdev->siblings);
233 INIT_LIST_HEAD(&sdev->same_target_siblings);
234 INIT_LIST_HEAD(&sdev->cmd_list);
235 INIT_LIST_HEAD(&sdev->starved_entry);
236 INIT_LIST_HEAD(&sdev->event_list);
237 spin_lock_init(&sdev->list_lock);
238 INIT_WORK(&sdev->event_work, scsi_evt_thread);
239 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
241 sdev->sdev_gendev.parent = get_device(&starget->dev);
242 sdev->sdev_target = starget;
244 /* usually NULL and set by ->slave_alloc instead */
245 sdev->hostdata = hostdata;
247 /* if the device needs this changing, it may do so in the
248 * slave_configure function */
249 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
252 * Some low level driver could use device->type
257 * Assume that the device will have handshaking problems,
258 * and then fix this field later if it turns out it
263 if (shost_use_blk_mq(shost))
264 sdev->request_queue = scsi_mq_alloc_queue(sdev);
266 sdev->request_queue = scsi_alloc_queue(sdev);
267 if (!sdev->request_queue) {
268 /* release fn is set up in scsi_sysfs_device_initialise, so
269 * have to free and put manually here */
270 put_device(&starget->dev);
274 WARN_ON_ONCE(!blk_get_queue(sdev->request_queue));
275 sdev->request_queue->queuedata = sdev;
277 if (!shost_use_blk_mq(sdev->host) &&
278 (shost->bqt || shost->hostt->use_blk_tags)) {
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);
285 scsi_sysfs_device_initialize(sdev);
287 if (shost->hostt->slave_alloc) {
288 ret = shost->hostt->slave_alloc(sdev);
291 * if LLDD reports slave not present, don't clutter
292 * console with alloc failure messages
295 display_failure_msg = 0;
296 goto out_device_destroy;
303 __scsi_remove_device(sdev);
305 if (display_failure_msg)
306 printk(ALLOC_FAILURE_MSG, __func__);
310 static void scsi_target_destroy(struct scsi_target *starget)
312 struct device *dev = &starget->dev;
313 struct Scsi_Host *shost = dev_to_shost(dev->parent);
316 starget->state = STARGET_DEL;
317 transport_destroy_device(dev);
318 spin_lock_irqsave(shost->host_lock, flags);
319 if (shost->hostt->target_destroy)
320 shost->hostt->target_destroy(starget);
321 list_del_init(&starget->siblings);
322 spin_unlock_irqrestore(shost->host_lock, flags);
326 static void scsi_target_dev_release(struct device *dev)
328 struct device *parent = dev->parent;
329 struct scsi_target *starget = to_scsi_target(dev);
335 static struct device_type scsi_target_type = {
336 .name = "scsi_target",
337 .release = scsi_target_dev_release,
340 int scsi_is_target_device(const struct device *dev)
342 return dev->type == &scsi_target_type;
344 EXPORT_SYMBOL(scsi_is_target_device);
346 static struct scsi_target *__scsi_find_target(struct device *parent,
347 int channel, uint id)
349 struct scsi_target *starget, *found_starget = NULL;
350 struct Scsi_Host *shost = dev_to_shost(parent);
352 * Search for an existing target for this sdev.
354 list_for_each_entry(starget, &shost->__targets, siblings) {
355 if (starget->id == id &&
356 starget->channel == channel) {
357 found_starget = starget;
362 get_device(&found_starget->dev);
364 return found_starget;
368 * scsi_target_reap_ref_release - remove target from visibility
369 * @kref: the reap_ref in the target being released
371 * Called on last put of reap_ref, which is the indication that no device
372 * under this target is visible anymore, so render the target invisible in
373 * sysfs. Note: we have to be in user context here because the target reaps
374 * should be done in places where the scsi device visibility is being removed.
376 static void scsi_target_reap_ref_release(struct kref *kref)
378 struct scsi_target *starget
379 = container_of(kref, struct scsi_target, reap_ref);
382 * if we get here and the target is still in the CREATED state that
383 * means it was allocated but never made visible (because a scan
384 * turned up no LUNs), so don't call device_del() on it.
386 if (starget->state != STARGET_CREATED) {
387 transport_remove_device(&starget->dev);
388 device_del(&starget->dev);
390 scsi_target_destroy(starget);
393 static void scsi_target_reap_ref_put(struct scsi_target *starget)
395 kref_put(&starget->reap_ref, scsi_target_reap_ref_release);
399 * scsi_alloc_target - allocate a new or find an existing target
400 * @parent: parent of the target (need not be a scsi host)
401 * @channel: target channel number (zero if no channels)
402 * @id: target id number
404 * Return an existing target if one exists, provided it hasn't already
405 * gone into STARGET_DEL state, otherwise allocate a new target.
407 * The target is returned with an incremented reference, so the caller
408 * is responsible for both reaping and doing a last put
410 static struct scsi_target *scsi_alloc_target(struct device *parent,
411 int channel, uint id)
413 struct Scsi_Host *shost = dev_to_shost(parent);
414 struct device *dev = NULL;
416 const int size = sizeof(struct scsi_target)
417 + shost->transportt->target_size;
418 struct scsi_target *starget;
419 struct scsi_target *found_target;
422 starget = kzalloc(size, GFP_KERNEL);
424 printk(KERN_ERR "%s: allocation failure\n", __func__);
428 device_initialize(dev);
429 kref_init(&starget->reap_ref);
430 dev->parent = get_device(parent);
431 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
432 dev->bus = &scsi_bus_type;
433 dev->type = &scsi_target_type;
435 starget->channel = channel;
436 starget->can_queue = 0;
437 INIT_LIST_HEAD(&starget->siblings);
438 INIT_LIST_HEAD(&starget->devices);
439 starget->state = STARGET_CREATED;
440 starget->scsi_level = SCSI_2;
441 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
443 spin_lock_irqsave(shost->host_lock, flags);
445 found_target = __scsi_find_target(parent, channel, id);
449 list_add_tail(&starget->siblings, &shost->__targets);
450 spin_unlock_irqrestore(shost->host_lock, flags);
451 /* allocate and add */
452 transport_setup_device(dev);
453 if (shost->hostt->target_alloc) {
454 error = shost->hostt->target_alloc(starget);
457 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
458 /* don't want scsi_target_reap to do the final
459 * put because it will be under the host lock */
460 scsi_target_destroy(starget);
470 * release routine already fired if kref is zero, so if we can still
471 * take the reference, the target must be alive. If we can't, it must
472 * be dying and we need to wait for a new target
474 ref_got = kref_get_unless_zero(&found_target->reap_ref);
476 spin_unlock_irqrestore(shost->host_lock, flags);
482 * Unfortunately, we found a dying target; need to wait until it's
483 * dead before we can get a new one. There is an anomaly here. We
484 * *should* call scsi_target_reap() to balance the kref_get() of the
485 * reap_ref above. However, since the target being released, it's
486 * already invisible and the reap_ref is irrelevant. If we call
487 * scsi_target_reap() we might spuriously do another device_del() on
488 * an already invisible target.
490 put_device(&found_target->dev);
492 * length of time is irrelevant here, we just want to yield the CPU
493 * for a tick to avoid busy waiting for the target to die.
500 * scsi_target_reap - check to see if target is in use and destroy if not
501 * @starget: target to be checked
503 * This is used after removing a LUN or doing a last put of the target
504 * it checks atomically that nothing is using the target and removes
507 void scsi_target_reap(struct scsi_target *starget)
510 * serious problem if this triggers: STARGET_DEL is only set in the if
511 * the reap_ref drops to zero, so we're trying to do another final put
512 * on an already released kref
514 BUG_ON(starget->state == STARGET_DEL);
515 scsi_target_reap_ref_put(starget);
519 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string
520 * @s: INQUIRY result string to sanitize
521 * @len: length of the string
524 * The SCSI spec says that INQUIRY vendor, product, and revision
525 * strings must consist entirely of graphic ASCII characters,
526 * padded on the right with spaces. Since not all devices obey
527 * this rule, we will replace non-graphic or non-ASCII characters
528 * with spaces. Exception: a NUL character is interpreted as a
529 * string terminator, so all the following characters are set to
532 static void sanitize_inquiry_string(unsigned char *s, int len)
536 for (; len > 0; (--len, ++s)) {
539 if (terminated || *s < 0x20 || *s > 0x7e)
545 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
546 * @sdev: scsi_device to probe
547 * @inq_result: area to store the INQUIRY result
548 * @result_len: len of inq_result
549 * @bflags: store any bflags found here
552 * Probe the lun associated with @req using a standard SCSI INQUIRY;
554 * If the INQUIRY is successful, zero is returned and the
555 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
556 * are copied to the scsi_device any flags value is stored in *@bflags.
558 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
559 int result_len, int *bflags)
561 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
562 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
563 int response_len = 0;
564 int pass, count, result;
565 struct scsi_sense_hdr sshdr;
569 /* Perform up to 3 passes. The first pass uses a conservative
570 * transfer length of 36 unless sdev->inquiry_len specifies a
571 * different value. */
572 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
573 try_inquiry_len = first_inquiry_len;
577 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
578 "scsi scan: INQUIRY pass %d length %d\n",
579 pass, try_inquiry_len));
581 /* Each pass gets up to three chances to ignore Unit Attention */
582 for (count = 0; count < 3; ++count) {
585 memset(scsi_cmd, 0, 6);
586 scsi_cmd[0] = INQUIRY;
587 scsi_cmd[4] = (unsigned char) try_inquiry_len;
589 memset(inq_result, 0, try_inquiry_len);
591 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
592 inq_result, try_inquiry_len, &sshdr,
593 HZ / 2 + HZ * scsi_inq_timeout, 3,
596 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
597 "scsi scan: INQUIRY %s with code 0x%x\n",
598 result ? "failed" : "successful", result));
602 * not-ready to ready transition [asc/ascq=0x28/0x0]
603 * or power-on, reset [asc/ascq=0x29/0x0], continue.
604 * INQUIRY should not yield UNIT_ATTENTION
605 * but many buggy devices do so anyway.
607 if ((driver_byte(result) & DRIVER_SENSE) &&
608 scsi_sense_valid(&sshdr)) {
609 if ((sshdr.sense_key == UNIT_ATTENTION) &&
610 ((sshdr.asc == 0x28) ||
611 (sshdr.asc == 0x29)) &&
617 * if nothing was transferred, we try
618 * again. It's a workaround for some USB
621 if (resid == try_inquiry_len)
628 sanitize_inquiry_string(&inq_result[8], 8);
629 sanitize_inquiry_string(&inq_result[16], 16);
630 sanitize_inquiry_string(&inq_result[32], 4);
632 response_len = inq_result[4] + 5;
633 if (response_len > 255)
634 response_len = first_inquiry_len; /* sanity */
637 * Get any flags for this device.
639 * XXX add a bflags to scsi_device, and replace the
640 * corresponding bit fields in scsi_device, so bflags
641 * need not be passed as an argument.
643 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
646 /* When the first pass succeeds we gain information about
647 * what larger transfer lengths might work. */
649 if (BLIST_INQUIRY_36 & *bflags)
650 next_inquiry_len = 36;
651 else if (BLIST_INQUIRY_58 & *bflags)
652 next_inquiry_len = 58;
653 else if (sdev->inquiry_len)
654 next_inquiry_len = sdev->inquiry_len;
656 next_inquiry_len = response_len;
658 /* If more data is available perform the second pass */
659 if (next_inquiry_len > try_inquiry_len) {
660 try_inquiry_len = next_inquiry_len;
666 } else if (pass == 2) {
667 sdev_printk(KERN_INFO, sdev,
668 "scsi scan: %d byte inquiry failed. "
669 "Consider BLIST_INQUIRY_36 for this device\n",
672 /* If this pass failed, the third pass goes back and transfers
673 * the same amount as we successfully got in the first pass. */
674 try_inquiry_len = first_inquiry_len;
679 /* If the last transfer attempt got an error, assume the
680 * peripheral doesn't exist or is dead. */
684 /* Don't report any more data than the device says is valid */
685 sdev->inquiry_len = min(try_inquiry_len, response_len);
688 * XXX Abort if the response length is less than 36? If less than
689 * 32, the lookup of the device flags (above) could be invalid,
690 * and it would be possible to take an incorrect action - we do
691 * not want to hang because of a short INQUIRY. On the flip side,
692 * if the device is spun down or becoming ready (and so it gives a
693 * short INQUIRY), an abort here prevents any further use of the
694 * device, including spin up.
696 * On the whole, the best approach seems to be to assume the first
697 * 36 bytes are valid no matter what the device says. That's
698 * better than copying < 36 bytes to the inquiry-result buffer
699 * and displaying garbage for the Vendor, Product, or Revision
702 if (sdev->inquiry_len < 36) {
703 sdev_printk(KERN_INFO, sdev,
704 "scsi scan: INQUIRY result too short (%d),"
705 " using 36\n", sdev->inquiry_len);
706 sdev->inquiry_len = 36;
710 * Related to the above issue:
712 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
713 * and if not ready, sent a START_STOP to start (maybe spin up) and
714 * then send the INQUIRY again, since the INQUIRY can change after
715 * a device is initialized.
717 * Ideally, start a device if explicitly asked to do so. This
718 * assumes that a device is spun up on power on, spun down on
719 * request, and then spun up on request.
723 * The scanning code needs to know the scsi_level, even if no
724 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
725 * non-zero LUNs can be scanned.
727 sdev->scsi_level = inq_result[2] & 0x07;
728 if (sdev->scsi_level >= 2 ||
729 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
731 sdev->sdev_target->scsi_level = sdev->scsi_level;
734 * If SCSI-2 or lower, and if the transport requires it,
735 * store the LUN value in CDB[1].
737 sdev->lun_in_cdb = 0;
738 if (sdev->scsi_level <= SCSI_2 &&
739 sdev->scsi_level != SCSI_UNKNOWN &&
740 !sdev->host->no_scsi2_lun_in_cdb)
741 sdev->lun_in_cdb = 1;
747 * scsi_add_lun - allocate and fully initialze a scsi_device
748 * @sdev: holds information to be stored in the new scsi_device
749 * @inq_result: holds the result of a previous INQUIRY to the LUN
750 * @bflags: black/white list flag
751 * @async: 1 if this device is being scanned asynchronously
754 * Initialize the scsi_device @sdev. Optionally set fields based
755 * on values in *@bflags.
758 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
759 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
761 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
762 int *bflags, int async)
767 * XXX do not save the inquiry, since it can change underneath us,
768 * save just vendor/model/rev.
770 * Rather than save it and have an ioctl that retrieves the saved
771 * value, have an ioctl that executes the same INQUIRY code used
772 * in scsi_probe_lun, let user level programs doing INQUIRY
773 * scanning run at their own risk, or supply a user level program
774 * that can correctly scan.
778 * Copy at least 36 bytes of INQUIRY data, so that we don't
779 * dereference unallocated memory when accessing the Vendor,
780 * Product, and Revision strings. Badly behaved devices may set
781 * the INQUIRY Additional Length byte to a small value, indicating
782 * these strings are invalid, but often they contain plausible data
783 * nonetheless. It doesn't matter if the device sent < 36 bytes
784 * total, since scsi_probe_lun() initializes inq_result with 0s.
786 sdev->inquiry = kmemdup(inq_result,
787 max_t(size_t, sdev->inquiry_len, 36),
789 if (sdev->inquiry == NULL)
790 return SCSI_SCAN_NO_RESPONSE;
792 sdev->vendor = (char *) (sdev->inquiry + 8);
793 sdev->model = (char *) (sdev->inquiry + 16);
794 sdev->rev = (char *) (sdev->inquiry + 32);
796 if (strncmp(sdev->vendor, "ATA ", 8) == 0) {
798 * sata emulation layer device. This is a hack to work around
799 * the SATL power management specifications which state that
800 * when the SATL detects the device has gone into standby
801 * mode, it shall respond with NOT READY.
803 sdev->allow_restart = 1;
806 if (*bflags & BLIST_ISROM) {
807 sdev->type = TYPE_ROM;
810 sdev->type = (inq_result[0] & 0x1f);
811 sdev->removable = (inq_result[1] & 0x80) >> 7;
814 * some devices may respond with wrong type for
815 * well-known logical units. Force well-known type
816 * to enumerate them correctly.
818 if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) {
819 sdev_printk(KERN_WARNING, sdev,
820 "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n",
821 __func__, sdev->type, (unsigned int)sdev->lun);
822 sdev->type = TYPE_WLUN;
827 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
828 /* RBC and MMC devices can return SCSI-3 compliance and yet
829 * still not support REPORT LUNS, so make them act as
830 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
831 * specifically set */
832 if ((*bflags & BLIST_REPORTLUN2) == 0)
833 *bflags |= BLIST_NOREPORTLUN;
837 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
838 * spec says: The device server is capable of supporting the
839 * specified peripheral device type on this logical unit. However,
840 * the physical device is not currently connected to this logical
843 * The above is vague, as it implies that we could treat 001 and
844 * 011 the same. Stay compatible with previous code, and create a
845 * scsi_device for a PQ of 1
847 * Don't set the device offline here; rather let the upper
848 * level drivers eval the PQ to decide whether they should
849 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
852 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
853 sdev->lockable = sdev->removable;
854 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
856 if (sdev->scsi_level >= SCSI_3 ||
857 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
859 if (inq_result[7] & 0x60)
861 if (inq_result[7] & 0x10)
864 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
865 "ANSI: %d%s\n", scsi_device_type(sdev->type),
866 sdev->vendor, sdev->model, sdev->rev,
867 sdev->inq_periph_qual, inq_result[2] & 0x07,
868 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
870 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
871 !(*bflags & BLIST_NOTQ)) {
872 sdev->tagged_supported = 1;
873 sdev->simple_tags = 1;
877 * Some devices (Texel CD ROM drives) have handshaking problems
878 * when used with the Seagate controllers. borken is initialized
879 * to 1, and then set it to 0 here.
881 if ((*bflags & BLIST_BORKEN) == 0)
884 if (*bflags & BLIST_NO_ULD_ATTACH)
885 sdev->no_uld_attach = 1;
888 * Apparently some really broken devices (contrary to the SCSI
889 * standards) need to be selected without asserting ATN
891 if (*bflags & BLIST_SELECT_NO_ATN)
892 sdev->select_no_atn = 1;
895 * Maximum 512 sector transfer length
896 * broken RA4x00 Compaq Disk Array
898 if (*bflags & BLIST_MAX_512)
899 blk_queue_max_hw_sectors(sdev->request_queue, 512);
901 * Max 1024 sector transfer length for targets that report incorrect
902 * max/optimal lengths and relied on the old block layer safe default
904 else if (*bflags & BLIST_MAX_1024)
905 blk_queue_max_hw_sectors(sdev->request_queue, 1024);
908 * Some devices may not want to have a start command automatically
909 * issued when a device is added.
911 if (*bflags & BLIST_NOSTARTONADD)
912 sdev->no_start_on_add = 1;
914 if (*bflags & BLIST_SINGLELUN)
915 scsi_target(sdev)->single_lun = 1;
917 sdev->use_10_for_rw = 1;
919 if (*bflags & BLIST_MS_SKIP_PAGE_08)
920 sdev->skip_ms_page_8 = 1;
922 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
923 sdev->skip_ms_page_3f = 1;
925 if (*bflags & BLIST_USE_10_BYTE_MS)
926 sdev->use_10_for_ms = 1;
928 /* some devices don't like REPORT SUPPORTED OPERATION CODES
929 * and will simply timeout causing sd_mod init to take a very
931 if (*bflags & BLIST_NO_RSOC)
932 sdev->no_report_opcodes = 1;
934 /* set the device running here so that slave configure
936 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
938 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
941 sdev_printk(KERN_ERR, sdev,
942 "in wrong state %s to complete scan\n",
943 scsi_device_state_name(sdev->sdev_state));
944 return SCSI_SCAN_NO_RESPONSE;
948 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
949 sdev->use_192_bytes_for_3f = 1;
951 if (*bflags & BLIST_NOT_LOCKABLE)
954 if (*bflags & BLIST_RETRY_HWERROR)
955 sdev->retry_hwerror = 1;
957 if (*bflags & BLIST_NO_DIF)
960 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
962 if (*bflags & BLIST_TRY_VPD_PAGES)
963 sdev->try_vpd_pages = 1;
964 else if (*bflags & BLIST_SKIP_VPD_PAGES)
965 sdev->skip_vpd_pages = 1;
967 transport_configure_device(&sdev->sdev_gendev);
969 if (sdev->host->hostt->slave_configure) {
970 ret = sdev->host->hostt->slave_configure(sdev);
973 * if LLDD reports slave not present, don't clutter
974 * console with alloc failure messages
977 sdev_printk(KERN_ERR, sdev,
978 "failed to configure device\n");
980 return SCSI_SCAN_NO_RESPONSE;
984 if (sdev->scsi_level >= SCSI_3)
985 scsi_attach_vpd(sdev);
987 sdev->max_queue_depth = sdev->queue_depth;
990 * Ok, the device is now all set up, we can
991 * register it and tell the rest of the kernel
994 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
995 return SCSI_SCAN_NO_RESPONSE;
997 return SCSI_SCAN_LUN_PRESENT;
1000 #ifdef CONFIG_SCSI_LOGGING
1002 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
1003 * @buf: Output buffer with at least end-first+1 bytes of space
1004 * @inq: Inquiry buffer (input)
1005 * @first: Offset of string into inq
1006 * @end: Index after last character in inq
1008 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
1009 unsigned first, unsigned end)
1011 unsigned term = 0, idx;
1013 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
1014 if (inq[idx+first] > ' ') {
1015 buf[idx] = inq[idx+first];
1027 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
1028 * @starget: pointer to target device structure
1029 * @lun: LUN of target device
1030 * @bflagsp: store bflags here if not NULL
1031 * @sdevp: probe the LUN corresponding to this scsi_device
1032 * @rescan: if nonzero skip some code only needed on first scan
1033 * @hostdata: passed to scsi_alloc_sdev()
1036 * Call scsi_probe_lun, if a LUN with an attached device is found,
1037 * allocate and set it up by calling scsi_add_lun.
1040 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1041 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1042 * attached at the LUN
1043 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1045 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1046 u64 lun, int *bflagsp,
1047 struct scsi_device **sdevp, int rescan,
1050 struct scsi_device *sdev;
1051 unsigned char *result;
1052 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1053 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1056 * The rescan flag is used as an optimization, the first scan of a
1057 * host adapter calls into here with rescan == 0.
1059 sdev = scsi_device_lookup_by_target(starget, lun);
1061 if (rescan || !scsi_device_created(sdev)) {
1062 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1063 "scsi scan: device exists on %s\n",
1064 dev_name(&sdev->sdev_gendev)));
1068 scsi_device_put(sdev);
1071 *bflagsp = scsi_get_device_flags(sdev,
1074 return SCSI_SCAN_LUN_PRESENT;
1076 scsi_device_put(sdev);
1078 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1082 result = kmalloc(result_len, GFP_ATOMIC |
1083 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
1087 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1088 goto out_free_result;
1093 * result contains valid SCSI INQUIRY data.
1095 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
1097 * For a Peripheral qualifier 3 (011b), the SCSI
1098 * spec says: The device server is not capable of
1099 * supporting a physical device on this logical
1102 * For disks, this implies that there is no
1103 * logical disk configured at sdev->lun, but there
1104 * is a target id responding.
1106 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1107 " peripheral qualifier of 3, device not"
1110 SCSI_LOG_SCAN_BUS(1, {
1111 unsigned char vend[9];
1112 unsigned char mod[17];
1114 sdev_printk(KERN_INFO, sdev,
1115 "scsi scan: consider passing scsi_mod."
1116 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1117 scsi_inq_str(vend, result, 8, 16),
1118 scsi_inq_str(mod, result, 16, 32));
1123 res = SCSI_SCAN_TARGET_PRESENT;
1124 goto out_free_result;
1128 * Some targets may set slight variations of PQ and PDT to signal
1129 * that no LUN is present, so don't add sdev in these cases.
1130 * Two specific examples are:
1131 * 1) NetApp targets: return PQ=1, PDT=0x1f
1132 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1133 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1136 * 1) SCSI SPC-3, pp. 145-146
1137 * PQ=1: "A peripheral device having the specified peripheral
1138 * device type is not connected to this logical unit. However, the
1139 * device server is capable of supporting the specified peripheral
1140 * device type on this logical unit."
1141 * PDT=0x1f: "Unknown or no device type"
1142 * 2) USB UFI 1.0, p. 20
1143 * PDT=00h Direct-access device (floppy)
1144 * PDT=1Fh none (no FDD connected to the requested logical unit)
1146 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1147 (result[0] & 0x1f) == 0x1f &&
1148 !scsi_is_wlun(lun)) {
1149 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
1150 "scsi scan: peripheral device type"
1151 " of 31, no device added\n"));
1152 res = SCSI_SCAN_TARGET_PRESENT;
1153 goto out_free_result;
1156 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1157 if (res == SCSI_SCAN_LUN_PRESENT) {
1158 if (bflags & BLIST_KEY) {
1160 scsi_unlock_floptical(sdev, result);
1167 if (res == SCSI_SCAN_LUN_PRESENT) {
1169 if (scsi_device_get(sdev) == 0) {
1172 __scsi_remove_device(sdev);
1173 res = SCSI_SCAN_NO_RESPONSE;
1177 __scsi_remove_device(sdev);
1183 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1184 * @starget: pointer to target structure to scan
1185 * @bflags: black/white list flag for LUN 0
1186 * @scsi_level: Which version of the standard does this device adhere to
1187 * @rescan: passed to scsi_probe_add_lun()
1190 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1191 * scanned) to some maximum lun until a LUN is found with no device
1192 * attached. Use the bflags to figure out any oddities.
1194 * Modifies sdevscan->lun.
1196 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1197 int bflags, int scsi_level, int rescan)
1200 u64 sparse_lun, lun;
1201 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1203 SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget,
1204 "scsi scan: Sequential scan\n"));
1206 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1208 * If this device is known to support sparse multiple units,
1209 * override the other settings, and scan all of them. Normally,
1210 * SCSI-3 devices should be scanned via the REPORT LUNS.
1212 if (bflags & BLIST_SPARSELUN) {
1213 max_dev_lun = shost->max_lun;
1219 * If less than SCSI_1_CCS, and no special lun scanning, stop
1220 * scanning; this matches 2.4 behaviour, but could just be a bug
1221 * (to continue scanning a SCSI_1_CCS device).
1223 * This test is broken. We might not have any device on lun0 for
1224 * a sparselun device, and if that's the case then how would we
1225 * know the real scsi_level, eh? It might make sense to just not
1226 * scan any SCSI_1 device for non-0 luns, but that check would best
1227 * go into scsi_alloc_sdev() and just have it return null when asked
1228 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1230 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1231 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1236 * If this device is known to support multiple units, override
1237 * the other settings, and scan all of them.
1239 if (bflags & BLIST_FORCELUN)
1240 max_dev_lun = shost->max_lun;
1242 * REGAL CDC-4X: avoid hang after LUN 4
1244 if (bflags & BLIST_MAX5LUN)
1245 max_dev_lun = min(5U, max_dev_lun);
1247 * Do not scan SCSI-2 or lower device past LUN 7, unless
1250 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1251 max_dev_lun = min(8U, max_dev_lun);
1254 * Stop scanning at 255 unless BLIST_SCSI3LUN
1256 if (!(bflags & BLIST_SCSI3LUN))
1257 max_dev_lun = min(256U, max_dev_lun);
1260 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1261 * until we reach the max, or no LUN is found and we are not
1264 for (lun = 1; lun < max_dev_lun; ++lun)
1265 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1266 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1272 * scsilun_to_int - convert a scsi_lun to an int
1273 * @scsilun: struct scsi_lun to be converted.
1276 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
1277 * integer, and return the result. The caller must check for
1278 * truncation before using this function.
1281 * For a description of the LUN format, post SCSI-3 see the SCSI
1282 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
1284 * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function
1285 * returns the integer: 0x0b03d204
1287 * This encoding will return a standard integer LUN for LUNs smaller
1288 * than 256, which typically use a single level LUN structure with
1289 * addressing method 0.
1291 u64 scsilun_to_int(struct scsi_lun *scsilun)
1297 for (i = 0; i < sizeof(lun); i += 2)
1298 lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) |
1299 ((u64)scsilun->scsi_lun[i + 1] << (i * 8)));
1302 EXPORT_SYMBOL(scsilun_to_int);
1305 * int_to_scsilun - reverts an int into a scsi_lun
1306 * @lun: integer to be reverted
1307 * @scsilun: struct scsi_lun to be set.
1310 * Reverts the functionality of the scsilun_to_int, which packed
1311 * an 8-byte lun value into an int. This routine unpacks the int
1312 * back into the lun value.
1315 * Given an integer : 0x0b03d204, this function returns a
1316 * struct scsi_lun of: d2 04 0b 03 00 00 00 00
1319 void int_to_scsilun(u64 lun, struct scsi_lun *scsilun)
1323 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
1325 for (i = 0; i < sizeof(lun); i += 2) {
1326 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
1327 scsilun->scsi_lun[i+1] = lun & 0xFF;
1331 EXPORT_SYMBOL(int_to_scsilun);
1334 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1335 * @starget: which target
1336 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1337 * @rescan: nonzero if we can skip code only needed on first scan
1340 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1341 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1343 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1344 * LUNs even if it's older than SCSI-3.
1345 * If BLIST_NOREPORTLUN is set, return 1 always.
1346 * If BLIST_NOLUN is set, return 0 always.
1347 * If starget->no_report_luns is set, return 1 always.
1350 * 0: scan completed (or no memory, so further scanning is futile)
1351 * 1: could not scan with REPORT LUN
1353 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1357 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1358 unsigned int length;
1360 unsigned int num_luns;
1361 unsigned int retries;
1363 struct scsi_lun *lunp, *lun_data;
1364 struct scsi_sense_hdr sshdr;
1365 struct scsi_device *sdev;
1366 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1370 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1371 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1372 * support more than 8 LUNs.
1373 * Don't attempt if the target doesn't support REPORT LUNS.
1375 if (bflags & BLIST_NOREPORTLUN)
1377 if (starget->scsi_level < SCSI_2 &&
1378 starget->scsi_level != SCSI_UNKNOWN)
1380 if (starget->scsi_level < SCSI_3 &&
1381 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1383 if (bflags & BLIST_NOLUN)
1385 if (starget->no_report_luns)
1388 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1389 sdev = scsi_alloc_sdev(starget, 0, NULL);
1392 if (scsi_device_get(sdev)) {
1393 __scsi_remove_device(sdev);
1398 sprintf(devname, "host %d channel %d id %d",
1399 shost->host_no, sdev->channel, sdev->id);
1402 * Allocate enough to hold the header (the same size as one scsi_lun)
1403 * plus the number of luns we are requesting. 511 was the default
1404 * value of the now removed max_report_luns parameter.
1406 length = (511 + 1) * sizeof(struct scsi_lun);
1408 lun_data = kmalloc(length, GFP_KERNEL |
1409 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1411 printk(ALLOC_FAILURE_MSG, __func__);
1415 scsi_cmd[0] = REPORT_LUNS;
1418 * bytes 1 - 5: reserved, set to zero.
1420 memset(&scsi_cmd[1], 0, 5);
1423 * bytes 6 - 9: length of the command.
1425 put_unaligned_be32(length, &scsi_cmd[6]);
1427 scsi_cmd[10] = 0; /* reserved */
1428 scsi_cmd[11] = 0; /* control */
1431 * We can get a UNIT ATTENTION, for example a power on/reset, so
1432 * retry a few times (like sd.c does for TEST UNIT READY).
1433 * Experience shows some combinations of adapter/devices get at
1434 * least two power on/resets.
1436 * Illegal requests (for devices that do not support REPORT LUNS)
1437 * should come through as a check condition, and will not generate
1440 for (retries = 0; retries < 3; retries++) {
1441 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1442 "scsi scan: Sending REPORT LUNS to (try %d)\n",
1445 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1446 lun_data, length, &sshdr,
1447 SCSI_TIMEOUT + 4 * HZ, 3, NULL);
1449 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1450 "scsi scan: REPORT LUNS"
1451 " %s (try %d) result 0x%x\n",
1452 result ? "failed" : "successful",
1456 else if (scsi_sense_valid(&sshdr)) {
1457 if (sshdr.sense_key != UNIT_ATTENTION)
1464 * The device probably does not support a REPORT LUN command
1471 * Get the length from the first four bytes of lun_data.
1473 if (get_unaligned_be32(lun_data->scsi_lun) +
1474 sizeof(struct scsi_lun) > length) {
1475 length = get_unaligned_be32(lun_data->scsi_lun) +
1476 sizeof(struct scsi_lun);
1480 length = get_unaligned_be32(lun_data->scsi_lun);
1482 num_luns = (length / sizeof(struct scsi_lun));
1484 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1485 "scsi scan: REPORT LUN scan\n"));
1488 * Scan the luns in lun_data. The entry at offset 0 is really
1489 * the header, so start at 1 and go up to and including num_luns.
1491 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1492 lun = scsilun_to_int(lunp);
1494 if (lun > sdev->host->max_lun) {
1495 sdev_printk(KERN_WARNING, sdev,
1496 "lun%llu has a LUN larger than"
1497 " allowed by the host adapter\n", lun);
1501 res = scsi_probe_and_add_lun(starget,
1502 lun, NULL, NULL, rescan, NULL);
1503 if (res == SCSI_SCAN_NO_RESPONSE) {
1505 * Got some results, but now none, abort.
1507 sdev_printk(KERN_ERR, sdev,
1508 "Unexpected response"
1509 " from lun %llu while scanning, scan"
1510 " aborted\n", (unsigned long long)lun);
1519 scsi_device_put(sdev);
1520 if (scsi_device_created(sdev))
1522 * the sdev we used didn't appear in the report luns scan
1524 __scsi_remove_device(sdev);
1528 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1529 uint id, u64 lun, void *hostdata)
1531 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1532 struct device *parent = &shost->shost_gendev;
1533 struct scsi_target *starget;
1535 if (strncmp(scsi_scan_type, "none", 4) == 0)
1536 return ERR_PTR(-ENODEV);
1538 starget = scsi_alloc_target(parent, channel, id);
1540 return ERR_PTR(-ENOMEM);
1541 scsi_autopm_get_target(starget);
1543 mutex_lock(&shost->scan_mutex);
1544 if (!shost->async_scan)
1545 scsi_complete_async_scans();
1547 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1548 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1549 scsi_autopm_put_host(shost);
1551 mutex_unlock(&shost->scan_mutex);
1552 scsi_autopm_put_target(starget);
1554 * paired with scsi_alloc_target(). Target will be destroyed unless
1555 * scsi_probe_and_add_lun made an underlying device visible
1557 scsi_target_reap(starget);
1558 put_device(&starget->dev);
1562 EXPORT_SYMBOL(__scsi_add_device);
1564 int scsi_add_device(struct Scsi_Host *host, uint channel,
1565 uint target, u64 lun)
1567 struct scsi_device *sdev =
1568 __scsi_add_device(host, channel, target, lun, NULL);
1570 return PTR_ERR(sdev);
1572 scsi_device_put(sdev);
1575 EXPORT_SYMBOL(scsi_add_device);
1577 void scsi_rescan_device(struct device *dev)
1580 if (dev->driver && try_module_get(dev->driver->owner)) {
1581 struct scsi_driver *drv = to_scsi_driver(dev->driver);
1585 module_put(dev->driver->owner);
1589 EXPORT_SYMBOL(scsi_rescan_device);
1591 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1592 unsigned int id, u64 lun, int rescan)
1594 struct Scsi_Host *shost = dev_to_shost(parent);
1597 struct scsi_target *starget;
1599 if (shost->this_id == id)
1601 * Don't scan the host adapter
1605 starget = scsi_alloc_target(parent, channel, id);
1608 scsi_autopm_get_target(starget);
1610 if (lun != SCAN_WILD_CARD) {
1612 * Scan for a specific host/chan/id/lun.
1614 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1619 * Scan LUN 0, if there is some response, scan further. Ideally, we
1620 * would not configure LUN 0 until all LUNs are scanned.
1622 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1623 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1624 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1626 * The REPORT LUN did not scan the target,
1627 * do a sequential scan.
1629 scsi_sequential_lun_scan(starget, bflags,
1630 starget->scsi_level, rescan);
1634 scsi_autopm_put_target(starget);
1636 * paired with scsi_alloc_target(): determine if the target has
1637 * any children at all and if not, nuke it
1639 scsi_target_reap(starget);
1641 put_device(&starget->dev);
1645 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1646 * @parent: host to scan
1647 * @channel: channel to scan
1648 * @id: target id to scan
1649 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1650 * @rescan: passed to LUN scanning routines
1653 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1654 * and possibly all LUNs on the target id.
1656 * First try a REPORT LUN scan, if that does not scan the target, do a
1657 * sequential scan of LUNs on the target id.
1659 void scsi_scan_target(struct device *parent, unsigned int channel,
1660 unsigned int id, u64 lun, int rescan)
1662 struct Scsi_Host *shost = dev_to_shost(parent);
1664 if (strncmp(scsi_scan_type, "none", 4) == 0)
1667 mutex_lock(&shost->scan_mutex);
1668 if (!shost->async_scan)
1669 scsi_complete_async_scans();
1671 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1672 __scsi_scan_target(parent, channel, id, lun, rescan);
1673 scsi_autopm_put_host(shost);
1675 mutex_unlock(&shost->scan_mutex);
1677 EXPORT_SYMBOL(scsi_scan_target);
1679 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1680 unsigned int id, u64 lun, int rescan)
1684 if (id == SCAN_WILD_CARD)
1685 for (id = 0; id < shost->max_id; ++id) {
1687 * XXX adapter drivers when possible (FCP, iSCSI)
1688 * could modify max_id to match the current max,
1689 * not the absolute max.
1691 * XXX add a shost id iterator, so for example,
1692 * the FC ID can be the same as a target id
1693 * without a huge overhead of sparse id's.
1695 if (shost->reverse_ordering)
1697 * Scan from high to low id.
1699 order_id = shost->max_id - id - 1;
1702 __scsi_scan_target(&shost->shost_gendev, channel,
1703 order_id, lun, rescan);
1706 __scsi_scan_target(&shost->shost_gendev, channel,
1710 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1711 unsigned int id, u64 lun, int rescan)
1713 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1714 "%s: <%u:%u:%llu>\n",
1715 __func__, channel, id, lun));
1717 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1718 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1719 ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun)))
1722 mutex_lock(&shost->scan_mutex);
1723 if (!shost->async_scan)
1724 scsi_complete_async_scans();
1726 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1727 if (channel == SCAN_WILD_CARD)
1728 for (channel = 0; channel <= shost->max_channel;
1730 scsi_scan_channel(shost, channel, id, lun,
1733 scsi_scan_channel(shost, channel, id, lun, rescan);
1734 scsi_autopm_put_host(shost);
1736 mutex_unlock(&shost->scan_mutex);
1741 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1743 struct scsi_device *sdev;
1744 shost_for_each_device(sdev, shost) {
1745 /* target removed before the device could be added */
1746 if (sdev->sdev_state == SDEV_DEL)
1748 /* If device is already visible, skip adding it to sysfs */
1749 if (sdev->is_visible)
1751 if (!scsi_host_scan_allowed(shost) ||
1752 scsi_sysfs_add_sdev(sdev) != 0)
1753 __scsi_remove_device(sdev);
1758 * scsi_prep_async_scan - prepare for an async scan
1759 * @shost: the host which will be scanned
1760 * Returns: a cookie to be passed to scsi_finish_async_scan()
1762 * Tells the midlayer this host is going to do an asynchronous scan.
1763 * It reserves the host's position in the scanning list and ensures
1764 * that other asynchronous scans started after this one won't affect the
1765 * ordering of the discovered devices.
1767 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1769 struct async_scan_data *data;
1770 unsigned long flags;
1772 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1775 if (shost->async_scan) {
1776 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
1781 data = kmalloc(sizeof(*data), GFP_KERNEL);
1784 data->shost = scsi_host_get(shost);
1787 init_completion(&data->prev_finished);
1789 mutex_lock(&shost->scan_mutex);
1790 spin_lock_irqsave(shost->host_lock, flags);
1791 shost->async_scan = 1;
1792 spin_unlock_irqrestore(shost->host_lock, flags);
1793 mutex_unlock(&shost->scan_mutex);
1795 spin_lock(&async_scan_lock);
1796 if (list_empty(&scanning_hosts))
1797 complete(&data->prev_finished);
1798 list_add_tail(&data->list, &scanning_hosts);
1799 spin_unlock(&async_scan_lock);
1809 * scsi_finish_async_scan - asynchronous scan has finished
1810 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1812 * All the devices currently attached to this host have been found.
1813 * This function announces all the devices it has found to the rest
1816 static void scsi_finish_async_scan(struct async_scan_data *data)
1818 struct Scsi_Host *shost;
1819 unsigned long flags;
1824 shost = data->shost;
1826 mutex_lock(&shost->scan_mutex);
1828 if (!shost->async_scan) {
1829 shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
1831 mutex_unlock(&shost->scan_mutex);
1835 wait_for_completion(&data->prev_finished);
1837 scsi_sysfs_add_devices(shost);
1839 spin_lock_irqsave(shost->host_lock, flags);
1840 shost->async_scan = 0;
1841 spin_unlock_irqrestore(shost->host_lock, flags);
1843 mutex_unlock(&shost->scan_mutex);
1845 spin_lock(&async_scan_lock);
1846 list_del(&data->list);
1847 if (!list_empty(&scanning_hosts)) {
1848 struct async_scan_data *next = list_entry(scanning_hosts.next,
1849 struct async_scan_data, list);
1850 complete(&next->prev_finished);
1852 spin_unlock(&async_scan_lock);
1854 scsi_autopm_put_host(shost);
1855 scsi_host_put(shost);
1859 static void do_scsi_scan_host(struct Scsi_Host *shost)
1861 if (shost->hostt->scan_finished) {
1862 unsigned long start = jiffies;
1863 if (shost->hostt->scan_start)
1864 shost->hostt->scan_start(shost);
1866 while (!shost->hostt->scan_finished(shost, jiffies - start))
1869 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1874 static void do_scan_async(void *_data, async_cookie_t c)
1876 struct async_scan_data *data = _data;
1877 struct Scsi_Host *shost = data->shost;
1879 do_scsi_scan_host(shost);
1880 scsi_finish_async_scan(data);
1884 * scsi_scan_host - scan the given adapter
1885 * @shost: adapter to scan
1887 void scsi_scan_host(struct Scsi_Host *shost)
1889 struct async_scan_data *data;
1891 if (strncmp(scsi_scan_type, "none", 4) == 0)
1893 if (scsi_autopm_get_host(shost) < 0)
1896 data = scsi_prep_async_scan(shost);
1898 do_scsi_scan_host(shost);
1899 scsi_autopm_put_host(shost);
1903 /* register with the async subsystem so wait_for_device_probe()
1904 * will flush this work
1906 async_schedule(do_scan_async, data);
1908 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
1910 EXPORT_SYMBOL(scsi_scan_host);
1912 void scsi_forget_host(struct Scsi_Host *shost)
1914 struct scsi_device *sdev;
1915 unsigned long flags;
1918 spin_lock_irqsave(shost->host_lock, flags);
1919 list_for_each_entry(sdev, &shost->__devices, siblings) {
1920 if (sdev->sdev_state == SDEV_DEL)
1922 spin_unlock_irqrestore(shost->host_lock, flags);
1923 __scsi_remove_device(sdev);
1926 spin_unlock_irqrestore(shost->host_lock, flags);
1930 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself
1931 * @shost: Host that needs a scsi_device
1933 * Lock status: None assumed.
1935 * Returns: The scsi_device or NULL
1938 * Attach a single scsi_device to the Scsi_Host - this should
1939 * be made to look like a "pseudo-device" that points to the
1942 * Note - this device is not accessible from any high-level
1943 * drivers (including generics), which is probably not
1944 * optimal. We can add hooks later to attach.
1946 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1948 struct scsi_device *sdev = NULL;
1949 struct scsi_target *starget;
1951 mutex_lock(&shost->scan_mutex);
1952 if (!scsi_host_scan_allowed(shost))
1954 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1958 sdev = scsi_alloc_sdev(starget, 0, NULL);
1962 scsi_target_reap(starget);
1963 put_device(&starget->dev);
1965 mutex_unlock(&shost->scan_mutex);
1968 EXPORT_SYMBOL(scsi_get_host_dev);
1971 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself
1972 * @sdev: Host device to be freed
1974 * Lock status: None assumed.
1978 void scsi_free_host_dev(struct scsi_device *sdev)
1980 BUG_ON(sdev->id != sdev->host->this_id);
1982 __scsi_remove_device(sdev);
1984 EXPORT_SYMBOL(scsi_free_host_dev);