4 * Copyright (C) 2000 Eric Youngdale,
5 * Copyright (C) 2002 Patrick Mansfield
7 * The general scanning/probing algorithm is as follows, exceptions are
8 * made to it depending on device specific flags, compilation options, and
9 * global variable (boot or module load time) settings.
11 * A specific LUN is scanned via an INQUIRY command; if the LUN has a
12 * device attached, a scsi_device is allocated and setup for it.
14 * For every id of every channel on the given host:
16 * Scan LUN 0; if the target responds to LUN 0 (even if there is no
17 * device or storage attached to LUN 0):
19 * If LUN 0 has a device attached, allocate and setup a
22 * If target is SCSI-3 or up, issue a REPORT LUN, and scan
23 * all of the LUNs returned by the REPORT LUN; else,
24 * sequentially scan LUNs up until some maximum is reached,
25 * or a LUN is seen that cannot have a device attached to it.
28 #include <linux/module.h>
29 #include <linux/moduleparam.h>
30 #include <linux/init.h>
31 #include <linux/blkdev.h>
32 #include <linux/delay.h>
33 #include <linux/kthread.h>
34 #include <linux/spinlock.h>
35 #include <linux/async.h>
36 #include <linux/slab.h>
38 #include <scsi/scsi.h>
39 #include <scsi/scsi_cmnd.h>
40 #include <scsi/scsi_device.h>
41 #include <scsi/scsi_driver.h>
42 #include <scsi/scsi_devinfo.h>
43 #include <scsi/scsi_host.h>
44 #include <scsi/scsi_transport.h>
45 #include <scsi/scsi_eh.h>
47 #include "scsi_priv.h"
48 #include "scsi_logging.h"
50 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
51 " SCSI scanning, some SCSI devices might not be configured\n"
56 #define SCSI_TIMEOUT (2*HZ)
59 * Prefix values for the SCSI id's (stored in sysfs name field)
61 #define SCSI_UID_SER_NUM 'S'
62 #define SCSI_UID_UNKNOWN 'Z'
65 * Return values of some of the scanning functions.
67 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
68 * includes allocation or general failures preventing IO from being sent.
70 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
73 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
76 #define SCSI_SCAN_NO_RESPONSE 0
77 #define SCSI_SCAN_TARGET_PRESENT 1
78 #define SCSI_SCAN_LUN_PRESENT 2
80 static const char *scsi_null_device_strs = "nullnullnullnull";
82 #define MAX_SCSI_LUNS 512
84 static u64 max_scsi_luns = MAX_SCSI_LUNS;
86 module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR);
87 MODULE_PARM_DESC(max_luns,
88 "last scsi LUN (should be between 1 and 2^64-1)");
90 #ifdef CONFIG_SCSI_SCAN_ASYNC
91 #define SCSI_SCAN_TYPE_DEFAULT "async"
93 #define SCSI_SCAN_TYPE_DEFAULT "sync"
96 char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT;
98 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
99 MODULE_PARM_DESC(scan, "sync, async or none");
102 * max_scsi_report_luns: the maximum number of LUNS that will be
103 * returned from the REPORT LUNS command. 8 times this value must
104 * be allocated. In theory this could be up to an 8 byte value, but
105 * in practice, the maximum number of LUNs suppored by any device
108 static unsigned int max_scsi_report_luns = 511;
110 module_param_named(max_report_luns, max_scsi_report_luns, uint, S_IRUGO|S_IWUSR);
111 MODULE_PARM_DESC(max_report_luns,
112 "REPORT LUNS maximum number of LUNS received (should be"
113 " between 1 and 16384)");
115 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
117 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
118 MODULE_PARM_DESC(inq_timeout,
119 "Timeout (in seconds) waiting for devices to answer INQUIRY."
120 " Default is 20. Some devices may need more; most need less.");
122 /* This lock protects only this list */
123 static DEFINE_SPINLOCK(async_scan_lock);
124 static LIST_HEAD(scanning_hosts);
126 struct async_scan_data {
127 struct list_head list;
128 struct Scsi_Host *shost;
129 struct completion prev_finished;
133 * scsi_complete_async_scans - Wait for asynchronous scans to complete
135 * When this function returns, any host which started scanning before
136 * this function was called will have finished its scan. Hosts which
137 * started scanning after this function was called may or may not have
140 int scsi_complete_async_scans(void)
142 struct async_scan_data *data;
145 if (list_empty(&scanning_hosts))
147 /* If we can't get memory immediately, that's OK. Just
148 * sleep a little. Even if we never get memory, the async
149 * scans will finish eventually.
151 data = kmalloc(sizeof(*data), GFP_KERNEL);
157 init_completion(&data->prev_finished);
159 spin_lock(&async_scan_lock);
160 /* Check that there's still somebody else on the list */
161 if (list_empty(&scanning_hosts))
163 list_add_tail(&data->list, &scanning_hosts);
164 spin_unlock(&async_scan_lock);
166 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
167 wait_for_completion(&data->prev_finished);
169 spin_lock(&async_scan_lock);
170 list_del(&data->list);
171 if (!list_empty(&scanning_hosts)) {
172 struct async_scan_data *next = list_entry(scanning_hosts.next,
173 struct async_scan_data, list);
174 complete(&next->prev_finished);
177 spin_unlock(&async_scan_lock);
184 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
185 * @sdev: scsi device to send command to
186 * @result: area to store the result of the MODE SENSE
189 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
190 * Called for BLIST_KEY devices.
192 static void scsi_unlock_floptical(struct scsi_device *sdev,
193 unsigned char *result)
195 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
197 printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
198 scsi_cmd[0] = MODE_SENSE;
202 scsi_cmd[4] = 0x2a; /* size */
204 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
205 SCSI_TIMEOUT, 3, NULL);
209 * scsi_alloc_sdev - allocate and setup a scsi_Device
210 * @starget: which target to allocate a &scsi_device for
212 * @hostdata: usually NULL and set by ->slave_alloc instead
215 * Allocate, initialize for io, and return a pointer to a scsi_Device.
216 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
217 * adds scsi_Device to the appropriate list.
220 * scsi_Device pointer, or NULL on failure.
222 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
223 u64 lun, void *hostdata)
225 struct scsi_device *sdev;
226 int display_failure_msg = 1, ret;
227 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
228 extern void scsi_evt_thread(struct work_struct *work);
229 extern void scsi_requeue_run_queue(struct work_struct *work);
231 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
236 sdev->vendor = scsi_null_device_strs;
237 sdev->model = scsi_null_device_strs;
238 sdev->rev = scsi_null_device_strs;
240 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
241 sdev->id = starget->id;
243 sdev->channel = starget->channel;
244 sdev->sdev_state = SDEV_CREATED;
245 INIT_LIST_HEAD(&sdev->siblings);
246 INIT_LIST_HEAD(&sdev->same_target_siblings);
247 INIT_LIST_HEAD(&sdev->cmd_list);
248 INIT_LIST_HEAD(&sdev->starved_entry);
249 INIT_LIST_HEAD(&sdev->event_list);
250 spin_lock_init(&sdev->list_lock);
251 INIT_WORK(&sdev->event_work, scsi_evt_thread);
252 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
254 sdev->sdev_gendev.parent = get_device(&starget->dev);
255 sdev->sdev_target = starget;
257 /* usually NULL and set by ->slave_alloc instead */
258 sdev->hostdata = hostdata;
260 /* if the device needs this changing, it may do so in the
261 * slave_configure function */
262 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
265 * Some low level driver could use device->type
270 * Assume that the device will have handshaking problems,
271 * and then fix this field later if it turns out it
276 sdev->request_queue = scsi_alloc_queue(sdev);
277 if (!sdev->request_queue) {
278 /* release fn is set up in scsi_sysfs_device_initialise, so
279 * have to free and put manually here */
280 put_device(&starget->dev);
284 WARN_ON_ONCE(!blk_get_queue(sdev->request_queue));
285 sdev->request_queue->queuedata = sdev;
286 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
288 scsi_sysfs_device_initialize(sdev);
290 if (shost->hostt->slave_alloc) {
291 ret = shost->hostt->slave_alloc(sdev);
294 * if LLDD reports slave not present, don't clutter
295 * console with alloc failure messages
298 display_failure_msg = 0;
299 goto out_device_destroy;
306 __scsi_remove_device(sdev);
308 if (display_failure_msg)
309 printk(ALLOC_FAILURE_MSG, __func__);
313 static void scsi_target_destroy(struct scsi_target *starget)
315 struct device *dev = &starget->dev;
316 struct Scsi_Host *shost = dev_to_shost(dev->parent);
319 starget->state = STARGET_DEL;
320 transport_destroy_device(dev);
321 spin_lock_irqsave(shost->host_lock, flags);
322 if (shost->hostt->target_destroy)
323 shost->hostt->target_destroy(starget);
324 list_del_init(&starget->siblings);
325 spin_unlock_irqrestore(shost->host_lock, flags);
329 static void scsi_target_dev_release(struct device *dev)
331 struct device *parent = dev->parent;
332 struct scsi_target *starget = to_scsi_target(dev);
338 static struct device_type scsi_target_type = {
339 .name = "scsi_target",
340 .release = scsi_target_dev_release,
343 int scsi_is_target_device(const struct device *dev)
345 return dev->type == &scsi_target_type;
347 EXPORT_SYMBOL(scsi_is_target_device);
349 static struct scsi_target *__scsi_find_target(struct device *parent,
350 int channel, uint id)
352 struct scsi_target *starget, *found_starget = NULL;
353 struct Scsi_Host *shost = dev_to_shost(parent);
355 * Search for an existing target for this sdev.
357 list_for_each_entry(starget, &shost->__targets, siblings) {
358 if (starget->id == id &&
359 starget->channel == channel) {
360 found_starget = starget;
365 get_device(&found_starget->dev);
367 return found_starget;
371 * scsi_target_reap_ref_release - remove target from visibility
372 * @kref: the reap_ref in the target being released
374 * Called on last put of reap_ref, which is the indication that no device
375 * under this target is visible anymore, so render the target invisible in
376 * sysfs. Note: we have to be in user context here because the target reaps
377 * should be done in places where the scsi device visibility is being removed.
379 static void scsi_target_reap_ref_release(struct kref *kref)
381 struct scsi_target *starget
382 = container_of(kref, struct scsi_target, reap_ref);
385 * if we get here and the target is still in the CREATED state that
386 * means it was allocated but never made visible (because a scan
387 * turned up no LUNs), so don't call device_del() on it.
389 if (starget->state != STARGET_CREATED) {
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, printk(KERN_INFO "scsi scan: INQUIRY %s "
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 printk(KERN_INFO "scsi scan: %d byte inquiry failed. "
671 "Consider BLIST_INQUIRY_36 for this device\n",
674 /* If this pass failed, the third pass goes back and transfers
675 * the same amount as we successfully got in the first pass. */
676 try_inquiry_len = first_inquiry_len;
681 /* If the last transfer attempt got an error, assume the
682 * peripheral doesn't exist or is dead. */
686 /* Don't report any more data than the device says is valid */
687 sdev->inquiry_len = min(try_inquiry_len, response_len);
690 * XXX Abort if the response length is less than 36? If less than
691 * 32, the lookup of the device flags (above) could be invalid,
692 * and it would be possible to take an incorrect action - we do
693 * not want to hang because of a short INQUIRY. On the flip side,
694 * if the device is spun down or becoming ready (and so it gives a
695 * short INQUIRY), an abort here prevents any further use of the
696 * device, including spin up.
698 * On the whole, the best approach seems to be to assume the first
699 * 36 bytes are valid no matter what the device says. That's
700 * better than copying < 36 bytes to the inquiry-result buffer
701 * and displaying garbage for the Vendor, Product, or Revision
704 if (sdev->inquiry_len < 36) {
705 printk(KERN_INFO "scsi scan: INQUIRY result too short (%d),"
706 " using 36\n", sdev->inquiry_len);
707 sdev->inquiry_len = 36;
711 * Related to the above issue:
713 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
714 * and if not ready, sent a START_STOP to start (maybe spin up) and
715 * then send the INQUIRY again, since the INQUIRY can change after
716 * a device is initialized.
718 * Ideally, start a device if explicitly asked to do so. This
719 * assumes that a device is spun up on power on, spun down on
720 * request, and then spun up on request.
724 * The scanning code needs to know the scsi_level, even if no
725 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
726 * non-zero LUNs can be scanned.
728 sdev->scsi_level = inq_result[2] & 0x07;
729 if (sdev->scsi_level >= 2 ||
730 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
732 sdev->sdev_target->scsi_level = sdev->scsi_level;
738 * scsi_add_lun - allocate and fully initialze a scsi_device
739 * @sdev: holds information to be stored in the new scsi_device
740 * @inq_result: holds the result of a previous INQUIRY to the LUN
741 * @bflags: black/white list flag
742 * @async: 1 if this device is being scanned asynchronously
745 * Initialize the scsi_device @sdev. Optionally set fields based
746 * on values in *@bflags.
749 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
750 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
752 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
753 int *bflags, int async)
758 * XXX do not save the inquiry, since it can change underneath us,
759 * save just vendor/model/rev.
761 * Rather than save it and have an ioctl that retrieves the saved
762 * value, have an ioctl that executes the same INQUIRY code used
763 * in scsi_probe_lun, let user level programs doing INQUIRY
764 * scanning run at their own risk, or supply a user level program
765 * that can correctly scan.
769 * Copy at least 36 bytes of INQUIRY data, so that we don't
770 * dereference unallocated memory when accessing the Vendor,
771 * Product, and Revision strings. Badly behaved devices may set
772 * the INQUIRY Additional Length byte to a small value, indicating
773 * these strings are invalid, but often they contain plausible data
774 * nonetheless. It doesn't matter if the device sent < 36 bytes
775 * total, since scsi_probe_lun() initializes inq_result with 0s.
777 sdev->inquiry = kmemdup(inq_result,
778 max_t(size_t, sdev->inquiry_len, 36),
780 if (sdev->inquiry == NULL)
781 return SCSI_SCAN_NO_RESPONSE;
783 sdev->vendor = (char *) (sdev->inquiry + 8);
784 sdev->model = (char *) (sdev->inquiry + 16);
785 sdev->rev = (char *) (sdev->inquiry + 32);
787 if (strncmp(sdev->vendor, "ATA ", 8) == 0) {
789 * sata emulation layer device. This is a hack to work around
790 * the SATL power management specifications which state that
791 * when the SATL detects the device has gone into standby
792 * mode, it shall respond with NOT READY.
794 sdev->allow_restart = 1;
797 if (*bflags & BLIST_ISROM) {
798 sdev->type = TYPE_ROM;
801 sdev->type = (inq_result[0] & 0x1f);
802 sdev->removable = (inq_result[1] & 0x80) >> 7;
805 switch (sdev->type) {
813 case TYPE_MEDIUM_CHANGER:
825 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
828 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
829 /* RBC and MMC devices can return SCSI-3 compliance and yet
830 * still not support REPORT LUNS, so make them act as
831 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
832 * specifically set */
833 if ((*bflags & BLIST_REPORTLUN2) == 0)
834 *bflags |= BLIST_NOREPORTLUN;
838 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
839 * spec says: The device server is capable of supporting the
840 * specified peripheral device type on this logical unit. However,
841 * the physical device is not currently connected to this logical
844 * The above is vague, as it implies that we could treat 001 and
845 * 011 the same. Stay compatible with previous code, and create a
846 * scsi_device for a PQ of 1
848 * Don't set the device offline here; rather let the upper
849 * level drivers eval the PQ to decide whether they should
850 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
853 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
854 sdev->lockable = sdev->removable;
855 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
857 if (sdev->scsi_level >= SCSI_3 ||
858 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
860 if (inq_result[7] & 0x60)
862 if (inq_result[7] & 0x10)
865 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
866 "ANSI: %d%s\n", scsi_device_type(sdev->type),
867 sdev->vendor, sdev->model, sdev->rev,
868 sdev->inq_periph_qual, inq_result[2] & 0x07,
869 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
871 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
872 !(*bflags & BLIST_NOTQ))
873 sdev->tagged_supported = 1;
876 * Some devices (Texel CD ROM drives) have handshaking problems
877 * when used with the Seagate controllers. borken is initialized
878 * to 1, and then set it to 0 here.
880 if ((*bflags & BLIST_BORKEN) == 0)
883 if (*bflags & BLIST_NO_ULD_ATTACH)
884 sdev->no_uld_attach = 1;
887 * Apparently some really broken devices (contrary to the SCSI
888 * standards) need to be selected without asserting ATN
890 if (*bflags & BLIST_SELECT_NO_ATN)
891 sdev->select_no_atn = 1;
894 * Maximum 512 sector transfer length
895 * broken RA4x00 Compaq Disk Array
897 if (*bflags & BLIST_MAX_512)
898 blk_queue_max_hw_sectors(sdev->request_queue, 512);
901 * Some devices may not want to have a start command automatically
902 * issued when a device is added.
904 if (*bflags & BLIST_NOSTARTONADD)
905 sdev->no_start_on_add = 1;
907 if (*bflags & BLIST_SINGLELUN)
908 scsi_target(sdev)->single_lun = 1;
910 sdev->use_10_for_rw = 1;
912 if (*bflags & BLIST_MS_SKIP_PAGE_08)
913 sdev->skip_ms_page_8 = 1;
915 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
916 sdev->skip_ms_page_3f = 1;
918 if (*bflags & BLIST_USE_10_BYTE_MS)
919 sdev->use_10_for_ms = 1;
921 /* set the device running here so that slave configure
923 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
925 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
928 sdev_printk(KERN_ERR, sdev,
929 "in wrong state %s to complete scan\n",
930 scsi_device_state_name(sdev->sdev_state));
931 return SCSI_SCAN_NO_RESPONSE;
935 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
936 sdev->use_192_bytes_for_3f = 1;
938 if (*bflags & BLIST_NOT_LOCKABLE)
941 if (*bflags & BLIST_RETRY_HWERROR)
942 sdev->retry_hwerror = 1;
944 if (*bflags & BLIST_NO_DIF)
947 sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
949 if (*bflags & BLIST_SKIP_VPD_PAGES)
950 sdev->skip_vpd_pages = 1;
952 transport_configure_device(&sdev->sdev_gendev);
954 if (sdev->host->hostt->slave_configure) {
955 ret = sdev->host->hostt->slave_configure(sdev);
958 * if LLDD reports slave not present, don't clutter
959 * console with alloc failure messages
962 sdev_printk(KERN_ERR, sdev,
963 "failed to configure device\n");
965 return SCSI_SCAN_NO_RESPONSE;
969 if (sdev->scsi_level >= SCSI_3)
970 scsi_attach_vpd(sdev);
972 sdev->max_queue_depth = sdev->queue_depth;
975 * Ok, the device is now all set up, we can
976 * register it and tell the rest of the kernel
979 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
980 return SCSI_SCAN_NO_RESPONSE;
982 return SCSI_SCAN_LUN_PRESENT;
985 #ifdef CONFIG_SCSI_LOGGING
987 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
988 * @buf: Output buffer with at least end-first+1 bytes of space
989 * @inq: Inquiry buffer (input)
990 * @first: Offset of string into inq
991 * @end: Index after last character in inq
993 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
994 unsigned first, unsigned end)
996 unsigned term = 0, idx;
998 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
999 if (inq[idx+first] > ' ') {
1000 buf[idx] = inq[idx+first];
1012 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
1013 * @starget: pointer to target device structure
1014 * @lun: LUN of target device
1015 * @bflagsp: store bflags here if not NULL
1016 * @sdevp: probe the LUN corresponding to this scsi_device
1017 * @rescan: if nonzero skip some code only needed on first scan
1018 * @hostdata: passed to scsi_alloc_sdev()
1021 * Call scsi_probe_lun, if a LUN with an attached device is found,
1022 * allocate and set it up by calling scsi_add_lun.
1025 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1026 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1027 * attached at the LUN
1028 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1030 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1031 u64 lun, int *bflagsp,
1032 struct scsi_device **sdevp, int rescan,
1035 struct scsi_device *sdev;
1036 unsigned char *result;
1037 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1038 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1041 * The rescan flag is used as an optimization, the first scan of a
1042 * host adapter calls into here with rescan == 0.
1044 sdev = scsi_device_lookup_by_target(starget, lun);
1046 if (rescan || !scsi_device_created(sdev)) {
1047 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1048 "scsi scan: device exists on %s\n",
1049 dev_name(&sdev->sdev_gendev)));
1053 scsi_device_put(sdev);
1056 *bflagsp = scsi_get_device_flags(sdev,
1059 return SCSI_SCAN_LUN_PRESENT;
1061 scsi_device_put(sdev);
1063 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1067 result = kmalloc(result_len, GFP_ATOMIC |
1068 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
1072 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1073 goto out_free_result;
1078 * result contains valid SCSI INQUIRY data.
1080 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
1082 * For a Peripheral qualifier 3 (011b), the SCSI
1083 * spec says: The device server is not capable of
1084 * supporting a physical device on this logical
1087 * For disks, this implies that there is no
1088 * logical disk configured at sdev->lun, but there
1089 * is a target id responding.
1091 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1092 " peripheral qualifier of 3, device not"
1095 SCSI_LOG_SCAN_BUS(1, {
1096 unsigned char vend[9];
1097 unsigned char mod[17];
1099 sdev_printk(KERN_INFO, sdev,
1100 "scsi scan: consider passing scsi_mod."
1101 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1102 scsi_inq_str(vend, result, 8, 16),
1103 scsi_inq_str(mod, result, 16, 32));
1108 res = SCSI_SCAN_TARGET_PRESENT;
1109 goto out_free_result;
1113 * Some targets may set slight variations of PQ and PDT to signal
1114 * that no LUN is present, so don't add sdev in these cases.
1115 * Two specific examples are:
1116 * 1) NetApp targets: return PQ=1, PDT=0x1f
1117 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1118 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1121 * 1) SCSI SPC-3, pp. 145-146
1122 * PQ=1: "A peripheral device having the specified peripheral
1123 * device type is not connected to this logical unit. However, the
1124 * device server is capable of supporting the specified peripheral
1125 * device type on this logical unit."
1126 * PDT=0x1f: "Unknown or no device type"
1127 * 2) USB UFI 1.0, p. 20
1128 * PDT=00h Direct-access device (floppy)
1129 * PDT=1Fh none (no FDD connected to the requested logical unit)
1131 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1132 (result[0] & 0x1f) == 0x1f &&
1133 !scsi_is_wlun(lun)) {
1134 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1135 "scsi scan: peripheral device type"
1136 " of 31, no device added\n"));
1137 res = SCSI_SCAN_TARGET_PRESENT;
1138 goto out_free_result;
1141 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1142 if (res == SCSI_SCAN_LUN_PRESENT) {
1143 if (bflags & BLIST_KEY) {
1145 scsi_unlock_floptical(sdev, result);
1152 if (res == SCSI_SCAN_LUN_PRESENT) {
1154 if (scsi_device_get(sdev) == 0) {
1157 __scsi_remove_device(sdev);
1158 res = SCSI_SCAN_NO_RESPONSE;
1162 __scsi_remove_device(sdev);
1168 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1169 * @starget: pointer to target structure to scan
1170 * @bflags: black/white list flag for LUN 0
1171 * @scsi_level: Which version of the standard does this device adhere to
1172 * @rescan: passed to scsi_probe_add_lun()
1175 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1176 * scanned) to some maximum lun until a LUN is found with no device
1177 * attached. Use the bflags to figure out any oddities.
1179 * Modifies sdevscan->lun.
1181 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1182 int bflags, int scsi_level, int rescan)
1185 u64 sparse_lun, lun;
1186 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1188 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
1189 "%s\n", dev_name(&starget->dev)));
1191 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1193 * If this device is known to support sparse multiple units,
1194 * override the other settings, and scan all of them. Normally,
1195 * SCSI-3 devices should be scanned via the REPORT LUNS.
1197 if (bflags & BLIST_SPARSELUN) {
1198 max_dev_lun = shost->max_lun;
1204 * If less than SCSI_1_CSS, and no special lun scaning, stop
1205 * scanning; this matches 2.4 behaviour, but could just be a bug
1206 * (to continue scanning a SCSI_1_CSS device).
1208 * This test is broken. We might not have any device on lun0 for
1209 * a sparselun device, and if that's the case then how would we
1210 * know the real scsi_level, eh? It might make sense to just not
1211 * scan any SCSI_1 device for non-0 luns, but that check would best
1212 * go into scsi_alloc_sdev() and just have it return null when asked
1213 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1215 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1216 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1221 * If this device is known to support multiple units, override
1222 * the other settings, and scan all of them.
1224 if (bflags & BLIST_FORCELUN)
1225 max_dev_lun = shost->max_lun;
1227 * REGAL CDC-4X: avoid hang after LUN 4
1229 if (bflags & BLIST_MAX5LUN)
1230 max_dev_lun = min(5U, max_dev_lun);
1232 * Do not scan SCSI-2 or lower device past LUN 7, unless
1235 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1236 max_dev_lun = min(8U, max_dev_lun);
1239 * Stop scanning at 255 unless BLIST_SCSI3LUN
1241 if (!(bflags & BLIST_SCSI3LUN))
1242 max_dev_lun = min(256U, max_dev_lun);
1245 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1246 * until we reach the max, or no LUN is found and we are not
1249 for (lun = 1; lun < max_dev_lun; ++lun)
1250 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1251 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1257 * scsilun_to_int - convert a scsi_lun to an int
1258 * @scsilun: struct scsi_lun to be converted.
1261 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
1262 * integer, and return the result. The caller must check for
1263 * truncation before using this function.
1266 * For a description of the LUN format, post SCSI-3 see the SCSI
1267 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
1269 * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function
1270 * returns the integer: 0x0b03d204
1272 * This encoding will return a standard integer LUN for LUNs smaller
1273 * than 256, which typically use a single level LUN structure with
1274 * addressing method 0.
1276 u64 scsilun_to_int(struct scsi_lun *scsilun)
1282 for (i = 0; i < sizeof(lun); i += 2)
1283 lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) |
1284 ((u64)scsilun->scsi_lun[i + 1] << (i * 8)));
1287 EXPORT_SYMBOL(scsilun_to_int);
1290 * int_to_scsilun - reverts an int into a scsi_lun
1291 * @lun: integer to be reverted
1292 * @scsilun: struct scsi_lun to be set.
1295 * Reverts the functionality of the scsilun_to_int, which packed
1296 * an 8-byte lun value into an int. This routine unpacks the int
1297 * back into the lun value.
1300 * Given an integer : 0x0b03d204, this function returns a
1301 * struct scsi_lun of: d2 04 0b 03 00 00 00 00
1304 void int_to_scsilun(u64 lun, struct scsi_lun *scsilun)
1308 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
1310 for (i = 0; i < sizeof(lun); i += 2) {
1311 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
1312 scsilun->scsi_lun[i+1] = lun & 0xFF;
1316 EXPORT_SYMBOL(int_to_scsilun);
1319 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1320 * @starget: which target
1321 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1322 * @rescan: nonzero if we can skip code only needed on first scan
1325 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1326 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1328 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1329 * LUNs even if it's older than SCSI-3.
1330 * If BLIST_NOREPORTLUN is set, return 1 always.
1331 * If BLIST_NOLUN is set, return 0 always.
1332 * If starget->no_report_luns is set, return 1 always.
1335 * 0: scan completed (or no memory, so further scanning is futile)
1336 * 1: could not scan with REPORT LUN
1338 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1342 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1343 unsigned int length;
1345 unsigned int num_luns;
1346 unsigned int retries;
1348 struct scsi_lun *lunp, *lun_data;
1350 struct scsi_sense_hdr sshdr;
1351 struct scsi_device *sdev;
1352 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1356 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1357 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1358 * support more than 8 LUNs.
1359 * Don't attempt if the target doesn't support REPORT LUNS.
1361 if (bflags & BLIST_NOREPORTLUN)
1363 if (starget->scsi_level < SCSI_2 &&
1364 starget->scsi_level != SCSI_UNKNOWN)
1366 if (starget->scsi_level < SCSI_3 &&
1367 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1369 if (bflags & BLIST_NOLUN)
1371 if (starget->no_report_luns)
1374 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1375 sdev = scsi_alloc_sdev(starget, 0, NULL);
1378 if (scsi_device_get(sdev)) {
1379 __scsi_remove_device(sdev);
1384 sprintf(devname, "host %d channel %d id %d",
1385 shost->host_no, sdev->channel, sdev->id);
1388 * Allocate enough to hold the header (the same size as one scsi_lun)
1389 * plus the max number of luns we are requesting.
1391 * Reallocating and trying again (with the exact amount we need)
1392 * would be nice, but then we need to somehow limit the size
1393 * allocated based on the available memory and the limits of
1394 * kmalloc - we don't want a kmalloc() failure of a huge value to
1395 * prevent us from finding any LUNs on this target.
1397 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
1398 lun_data = kmalloc(length, GFP_ATOMIC |
1399 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1401 printk(ALLOC_FAILURE_MSG, __func__);
1405 scsi_cmd[0] = REPORT_LUNS;
1408 * bytes 1 - 5: reserved, set to zero.
1410 memset(&scsi_cmd[1], 0, 5);
1413 * bytes 6 - 9: length of the command.
1415 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
1416 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
1417 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
1418 scsi_cmd[9] = (unsigned char) length & 0xff;
1420 scsi_cmd[10] = 0; /* reserved */
1421 scsi_cmd[11] = 0; /* control */
1424 * We can get a UNIT ATTENTION, for example a power on/reset, so
1425 * retry a few times (like sd.c does for TEST UNIT READY).
1426 * Experience shows some combinations of adapter/devices get at
1427 * least two power on/resets.
1429 * Illegal requests (for devices that do not support REPORT LUNS)
1430 * should come through as a check condition, and will not generate
1433 for (retries = 0; retries < 3; retries++) {
1434 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
1435 " REPORT LUNS to %s (try %d)\n", devname,
1438 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1439 lun_data, length, &sshdr,
1440 SCSI_TIMEOUT + 4 * HZ, 3, NULL);
1442 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
1443 " %s (try %d) result 0x%x\n", result
1444 ? "failed" : "successful", retries, result));
1447 else if (scsi_sense_valid(&sshdr)) {
1448 if (sshdr.sense_key != UNIT_ATTENTION)
1455 * The device probably does not support a REPORT LUN command
1462 * Get the length from the first four bytes of lun_data.
1464 data = (u8 *) lun_data->scsi_lun;
1465 length = ((data[0] << 24) | (data[1] << 16) |
1466 (data[2] << 8) | (data[3] << 0));
1468 num_luns = (length / sizeof(struct scsi_lun));
1469 if (num_luns > max_scsi_report_luns) {
1470 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1471 " of %d luns reported, try increasing"
1472 " max_scsi_report_luns.\n", devname,
1473 max_scsi_report_luns, num_luns);
1474 num_luns = max_scsi_report_luns;
1477 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1478 "scsi scan: REPORT LUN scan\n"));
1481 * Scan the luns in lun_data. The entry at offset 0 is really
1482 * the header, so start at 1 and go up to and including num_luns.
1484 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1485 lun = scsilun_to_int(lunp);
1487 if (lun > sdev->host->max_lun) {
1488 printk(KERN_WARNING "scsi: %s lun%llu has a LUN larger"
1489 " than allowed by the host adapter\n",
1494 res = scsi_probe_and_add_lun(starget,
1495 lun, NULL, NULL, rescan, NULL);
1496 if (res == SCSI_SCAN_NO_RESPONSE) {
1498 * Got some results, but now none, abort.
1500 sdev_printk(KERN_ERR, sdev,
1501 "Unexpected response"
1502 " from lun %llu while scanning, scan"
1503 " aborted\n", (unsigned long long)lun);
1512 scsi_device_put(sdev);
1513 if (scsi_device_created(sdev))
1515 * the sdev we used didn't appear in the report luns scan
1517 __scsi_remove_device(sdev);
1521 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1522 uint id, u64 lun, void *hostdata)
1524 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1525 struct device *parent = &shost->shost_gendev;
1526 struct scsi_target *starget;
1528 if (strncmp(scsi_scan_type, "none", 4) == 0)
1529 return ERR_PTR(-ENODEV);
1531 starget = scsi_alloc_target(parent, channel, id);
1533 return ERR_PTR(-ENOMEM);
1534 scsi_autopm_get_target(starget);
1536 mutex_lock(&shost->scan_mutex);
1537 if (!shost->async_scan)
1538 scsi_complete_async_scans();
1540 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1541 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1542 scsi_autopm_put_host(shost);
1544 mutex_unlock(&shost->scan_mutex);
1545 scsi_autopm_put_target(starget);
1547 * paired with scsi_alloc_target(). Target will be destroyed unless
1548 * scsi_probe_and_add_lun made an underlying device visible
1550 scsi_target_reap(starget);
1551 put_device(&starget->dev);
1555 EXPORT_SYMBOL(__scsi_add_device);
1557 int scsi_add_device(struct Scsi_Host *host, uint channel,
1558 uint target, u64 lun)
1560 struct scsi_device *sdev =
1561 __scsi_add_device(host, channel, target, lun, NULL);
1563 return PTR_ERR(sdev);
1565 scsi_device_put(sdev);
1568 EXPORT_SYMBOL(scsi_add_device);
1570 void scsi_rescan_device(struct device *dev)
1572 struct scsi_driver *drv;
1577 drv = to_scsi_driver(dev->driver);
1578 if (try_module_get(drv->owner)) {
1581 module_put(drv->owner);
1584 EXPORT_SYMBOL(scsi_rescan_device);
1586 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1587 unsigned int id, u64 lun, int rescan)
1589 struct Scsi_Host *shost = dev_to_shost(parent);
1592 struct scsi_target *starget;
1594 if (shost->this_id == id)
1596 * Don't scan the host adapter
1600 starget = scsi_alloc_target(parent, channel, id);
1603 scsi_autopm_get_target(starget);
1605 if (lun != SCAN_WILD_CARD) {
1607 * Scan for a specific host/chan/id/lun.
1609 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1614 * Scan LUN 0, if there is some response, scan further. Ideally, we
1615 * would not configure LUN 0 until all LUNs are scanned.
1617 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1618 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1619 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1621 * The REPORT LUN did not scan the target,
1622 * do a sequential scan.
1624 scsi_sequential_lun_scan(starget, bflags,
1625 starget->scsi_level, rescan);
1629 scsi_autopm_put_target(starget);
1631 * paired with scsi_alloc_target(): determine if the target has
1632 * any children at all and if not, nuke it
1634 scsi_target_reap(starget);
1636 put_device(&starget->dev);
1640 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1641 * @parent: host to scan
1642 * @channel: channel to scan
1643 * @id: target id to scan
1644 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1645 * @rescan: passed to LUN scanning routines
1648 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1649 * and possibly all LUNs on the target id.
1651 * First try a REPORT LUN scan, if that does not scan the target, do a
1652 * sequential scan of LUNs on the target id.
1654 void scsi_scan_target(struct device *parent, unsigned int channel,
1655 unsigned int id, u64 lun, int rescan)
1657 struct Scsi_Host *shost = dev_to_shost(parent);
1659 if (strncmp(scsi_scan_type, "none", 4) == 0)
1662 mutex_lock(&shost->scan_mutex);
1663 if (!shost->async_scan)
1664 scsi_complete_async_scans();
1666 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1667 __scsi_scan_target(parent, channel, id, lun, rescan);
1668 scsi_autopm_put_host(shost);
1670 mutex_unlock(&shost->scan_mutex);
1672 EXPORT_SYMBOL(scsi_scan_target);
1674 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1675 unsigned int id, u64 lun, int rescan)
1679 if (id == SCAN_WILD_CARD)
1680 for (id = 0; id < shost->max_id; ++id) {
1682 * XXX adapter drivers when possible (FCP, iSCSI)
1683 * could modify max_id to match the current max,
1684 * not the absolute max.
1686 * XXX add a shost id iterator, so for example,
1687 * the FC ID can be the same as a target id
1688 * without a huge overhead of sparse id's.
1690 if (shost->reverse_ordering)
1692 * Scan from high to low id.
1694 order_id = shost->max_id - id - 1;
1697 __scsi_scan_target(&shost->shost_gendev, channel,
1698 order_id, lun, rescan);
1701 __scsi_scan_target(&shost->shost_gendev, channel,
1705 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1706 unsigned int id, u64 lun, int rescan)
1708 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1709 "%s: <%u:%u:%llu>\n",
1710 __func__, channel, id, lun));
1712 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1713 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1714 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1717 mutex_lock(&shost->scan_mutex);
1718 if (!shost->async_scan)
1719 scsi_complete_async_scans();
1721 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1722 if (channel == SCAN_WILD_CARD)
1723 for (channel = 0; channel <= shost->max_channel;
1725 scsi_scan_channel(shost, channel, id, lun,
1728 scsi_scan_channel(shost, channel, id, lun, rescan);
1729 scsi_autopm_put_host(shost);
1731 mutex_unlock(&shost->scan_mutex);
1736 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1738 struct scsi_device *sdev;
1739 shost_for_each_device(sdev, shost) {
1740 /* target removed before the device could be added */
1741 if (sdev->sdev_state == SDEV_DEL)
1743 if (!scsi_host_scan_allowed(shost) ||
1744 scsi_sysfs_add_sdev(sdev) != 0)
1745 __scsi_remove_device(sdev);
1750 * scsi_prep_async_scan - prepare for an async scan
1751 * @shost: the host which will be scanned
1752 * Returns: a cookie to be passed to scsi_finish_async_scan()
1754 * Tells the midlayer this host is going to do an asynchronous scan.
1755 * It reserves the host's position in the scanning list and ensures
1756 * that other asynchronous scans started after this one won't affect the
1757 * ordering of the discovered devices.
1759 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1761 struct async_scan_data *data;
1762 unsigned long flags;
1764 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1767 if (shost->async_scan) {
1768 printk("%s called twice for host %d", __func__,
1774 data = kmalloc(sizeof(*data), GFP_KERNEL);
1777 data->shost = scsi_host_get(shost);
1780 init_completion(&data->prev_finished);
1782 mutex_lock(&shost->scan_mutex);
1783 spin_lock_irqsave(shost->host_lock, flags);
1784 shost->async_scan = 1;
1785 spin_unlock_irqrestore(shost->host_lock, flags);
1786 mutex_unlock(&shost->scan_mutex);
1788 spin_lock(&async_scan_lock);
1789 if (list_empty(&scanning_hosts))
1790 complete(&data->prev_finished);
1791 list_add_tail(&data->list, &scanning_hosts);
1792 spin_unlock(&async_scan_lock);
1802 * scsi_finish_async_scan - asynchronous scan has finished
1803 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1805 * All the devices currently attached to this host have been found.
1806 * This function announces all the devices it has found to the rest
1809 static void scsi_finish_async_scan(struct async_scan_data *data)
1811 struct Scsi_Host *shost;
1812 unsigned long flags;
1817 shost = data->shost;
1819 mutex_lock(&shost->scan_mutex);
1821 if (!shost->async_scan) {
1822 printk("%s called twice for host %d", __func__,
1825 mutex_unlock(&shost->scan_mutex);
1829 wait_for_completion(&data->prev_finished);
1831 scsi_sysfs_add_devices(shost);
1833 spin_lock_irqsave(shost->host_lock, flags);
1834 shost->async_scan = 0;
1835 spin_unlock_irqrestore(shost->host_lock, flags);
1837 mutex_unlock(&shost->scan_mutex);
1839 spin_lock(&async_scan_lock);
1840 list_del(&data->list);
1841 if (!list_empty(&scanning_hosts)) {
1842 struct async_scan_data *next = list_entry(scanning_hosts.next,
1843 struct async_scan_data, list);
1844 complete(&next->prev_finished);
1846 spin_unlock(&async_scan_lock);
1848 scsi_autopm_put_host(shost);
1849 scsi_host_put(shost);
1853 static void do_scsi_scan_host(struct Scsi_Host *shost)
1855 if (shost->hostt->scan_finished) {
1856 unsigned long start = jiffies;
1857 if (shost->hostt->scan_start)
1858 shost->hostt->scan_start(shost);
1860 while (!shost->hostt->scan_finished(shost, jiffies - start))
1863 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1868 static void do_scan_async(void *_data, async_cookie_t c)
1870 struct async_scan_data *data = _data;
1871 struct Scsi_Host *shost = data->shost;
1873 do_scsi_scan_host(shost);
1874 scsi_finish_async_scan(data);
1878 * scsi_scan_host - scan the given adapter
1879 * @shost: adapter to scan
1881 void scsi_scan_host(struct Scsi_Host *shost)
1883 struct async_scan_data *data;
1885 if (strncmp(scsi_scan_type, "none", 4) == 0)
1887 if (scsi_autopm_get_host(shost) < 0)
1890 data = scsi_prep_async_scan(shost);
1892 do_scsi_scan_host(shost);
1893 scsi_autopm_put_host(shost);
1897 /* register with the async subsystem so wait_for_device_probe()
1898 * will flush this work
1900 async_schedule(do_scan_async, data);
1902 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
1904 EXPORT_SYMBOL(scsi_scan_host);
1906 void scsi_forget_host(struct Scsi_Host *shost)
1908 struct scsi_device *sdev;
1909 unsigned long flags;
1912 spin_lock_irqsave(shost->host_lock, flags);
1913 list_for_each_entry(sdev, &shost->__devices, siblings) {
1914 if (sdev->sdev_state == SDEV_DEL)
1916 spin_unlock_irqrestore(shost->host_lock, flags);
1917 __scsi_remove_device(sdev);
1920 spin_unlock_irqrestore(shost->host_lock, flags);
1924 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself
1925 * @shost: Host that needs a scsi_device
1927 * Lock status: None assumed.
1929 * Returns: The scsi_device or NULL
1932 * Attach a single scsi_device to the Scsi_Host - this should
1933 * be made to look like a "pseudo-device" that points to the
1936 * Note - this device is not accessible from any high-level
1937 * drivers (including generics), which is probably not
1938 * optimal. We can add hooks later to attach.
1940 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1942 struct scsi_device *sdev = NULL;
1943 struct scsi_target *starget;
1945 mutex_lock(&shost->scan_mutex);
1946 if (!scsi_host_scan_allowed(shost))
1948 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1952 sdev = scsi_alloc_sdev(starget, 0, NULL);
1956 scsi_target_reap(starget);
1957 put_device(&starget->dev);
1959 mutex_unlock(&shost->scan_mutex);
1962 EXPORT_SYMBOL(scsi_get_host_dev);
1965 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself
1966 * @sdev: Host device to be freed
1968 * Lock status: None assumed.
1972 void scsi_free_host_dev(struct scsi_device *sdev)
1974 BUG_ON(sdev->id != sdev->host->this_id);
1976 __scsi_remove_device(sdev);
1978 EXPORT_SYMBOL(scsi_free_host_dev);