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>
36 #include <scsi/scsi.h>
37 #include <scsi/scsi_cmnd.h>
38 #include <scsi/scsi_device.h>
39 #include <scsi/scsi_driver.h>
40 #include <scsi/scsi_devinfo.h>
41 #include <scsi/scsi_host.h>
42 #include <scsi/scsi_transport.h>
43 #include <scsi/scsi_eh.h>
45 #include "scsi_priv.h"
46 #include "scsi_logging.h"
48 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
49 " SCSI scanning, some SCSI devices might not be configured\n"
54 #define SCSI_TIMEOUT (2*HZ)
57 * Prefix values for the SCSI id's (stored in driverfs name field)
59 #define SCSI_UID_SER_NUM 'S'
60 #define SCSI_UID_UNKNOWN 'Z'
63 * Return values of some of the scanning functions.
65 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
66 * includes allocation or general failures preventing IO from being sent.
68 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
71 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
74 #define SCSI_SCAN_NO_RESPONSE 0
75 #define SCSI_SCAN_TARGET_PRESENT 1
76 #define SCSI_SCAN_LUN_PRESENT 2
78 static const char *scsi_null_device_strs = "nullnullnullnull";
80 #define MAX_SCSI_LUNS 512
82 #ifdef CONFIG_SCSI_MULTI_LUN
83 static unsigned int max_scsi_luns = MAX_SCSI_LUNS;
85 static unsigned int max_scsi_luns = 1;
88 module_param_named(max_luns, max_scsi_luns, int, S_IRUGO|S_IWUSR);
89 MODULE_PARM_DESC(max_luns,
90 "last scsi LUN (should be between 1 and 2^32-1)");
92 static char scsi_scan_type[6] = "sync";
94 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
95 MODULE_PARM_DESC(scan, "sync, async or none");
98 * max_scsi_report_luns: the maximum number of LUNS that will be
99 * returned from the REPORT LUNS command. 8 times this value must
100 * be allocated. In theory this could be up to an 8 byte value, but
101 * in practice, the maximum number of LUNs suppored by any device
104 static unsigned int max_scsi_report_luns = 511;
106 module_param_named(max_report_luns, max_scsi_report_luns, int, S_IRUGO|S_IWUSR);
107 MODULE_PARM_DESC(max_report_luns,
108 "REPORT LUNS maximum number of LUNS received (should be"
109 " between 1 and 16384)");
111 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ+3;
113 module_param_named(inq_timeout, scsi_inq_timeout, int, S_IRUGO|S_IWUSR);
114 MODULE_PARM_DESC(inq_timeout,
115 "Timeout (in seconds) waiting for devices to answer INQUIRY."
116 " Default is 5. Some non-compliant devices need more.");
118 static DEFINE_SPINLOCK(async_scan_lock);
119 static LIST_HEAD(scanning_hosts);
121 struct async_scan_data {
122 struct list_head list;
123 struct Scsi_Host *shost;
124 struct completion prev_finished;
128 * scsi_complete_async_scans - Wait for asynchronous scans to complete
130 * Asynchronous scans add themselves to the scanning_hosts list. Once
131 * that list is empty, we know that the scans are complete. Rather than
132 * waking up periodically to check the state of the list, we pretend to be
133 * a scanning task by adding ourselves at the end of the list and going to
134 * sleep. When the task before us wakes us up, we take ourselves off the
137 int scsi_complete_async_scans(void)
139 struct async_scan_data *data;
142 if (list_empty(&scanning_hosts))
144 /* If we can't get memory immediately, that's OK. Just
145 * sleep a little. Even if we never get memory, the async
146 * scans will finish eventually.
148 data = kmalloc(sizeof(*data), GFP_KERNEL);
154 init_completion(&data->prev_finished);
156 spin_lock(&async_scan_lock);
157 /* Check that there's still somebody else on the list */
158 if (list_empty(&scanning_hosts))
160 list_add_tail(&data->list, &scanning_hosts);
161 spin_unlock(&async_scan_lock);
163 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
164 wait_for_completion(&data->prev_finished);
166 spin_lock(&async_scan_lock);
167 list_del(&data->list);
169 spin_unlock(&async_scan_lock);
176 /* Only exported for the benefit of scsi_wait_scan */
177 EXPORT_SYMBOL_GPL(scsi_complete_async_scans);
181 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
182 * @sdev: scsi device to send command to
183 * @result: area to store the result of the MODE SENSE
186 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
187 * Called for BLIST_KEY devices.
189 static void scsi_unlock_floptical(struct scsi_device *sdev,
190 unsigned char *result)
192 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
194 printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
195 scsi_cmd[0] = MODE_SENSE;
199 scsi_cmd[4] = 0x2a; /* size */
201 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
206 * scsi_alloc_sdev - allocate and setup a scsi_Device
209 * Allocate, initialize for io, and return a pointer to a scsi_Device.
210 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
211 * adds scsi_Device to the appropriate list.
214 * scsi_Device pointer, or NULL on failure.
216 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
217 unsigned int lun, void *hostdata)
219 struct scsi_device *sdev;
220 int display_failure_msg = 1, ret;
221 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
223 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
228 sdev->vendor = scsi_null_device_strs;
229 sdev->model = scsi_null_device_strs;
230 sdev->rev = scsi_null_device_strs;
232 sdev->id = starget->id;
234 sdev->channel = starget->channel;
235 sdev->sdev_state = SDEV_CREATED;
236 INIT_LIST_HEAD(&sdev->siblings);
237 INIT_LIST_HEAD(&sdev->same_target_siblings);
238 INIT_LIST_HEAD(&sdev->cmd_list);
239 INIT_LIST_HEAD(&sdev->starved_entry);
240 spin_lock_init(&sdev->list_lock);
242 sdev->sdev_gendev.parent = get_device(&starget->dev);
243 sdev->sdev_target = starget;
245 /* usually NULL and set by ->slave_alloc instead */
246 sdev->hostdata = hostdata;
248 /* if the device needs this changing, it may do so in the
249 * slave_configure function */
250 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
253 * Some low level driver could use device->type
258 * Assume that the device will have handshaking problems,
259 * and then fix this field later if it turns out it
264 sdev->request_queue = scsi_alloc_queue(sdev);
265 if (!sdev->request_queue) {
266 /* release fn is set up in scsi_sysfs_device_initialise, so
267 * have to free and put manually here */
268 put_device(&starget->dev);
273 sdev->request_queue->queuedata = sdev;
274 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
276 scsi_sysfs_device_initialize(sdev);
278 if (shost->hostt->slave_alloc) {
279 ret = shost->hostt->slave_alloc(sdev);
282 * if LLDD reports slave not present, don't clutter
283 * console with alloc failure messages
286 display_failure_msg = 0;
287 goto out_device_destroy;
294 transport_destroy_device(&sdev->sdev_gendev);
295 put_device(&sdev->sdev_gendev);
297 if (display_failure_msg)
298 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
302 static void scsi_target_dev_release(struct device *dev)
304 struct device *parent = dev->parent;
305 struct scsi_target *starget = to_scsi_target(dev);
311 int scsi_is_target_device(const struct device *dev)
313 return dev->release == scsi_target_dev_release;
315 EXPORT_SYMBOL(scsi_is_target_device);
317 static struct scsi_target *__scsi_find_target(struct device *parent,
318 int channel, uint id)
320 struct scsi_target *starget, *found_starget = NULL;
321 struct Scsi_Host *shost = dev_to_shost(parent);
323 * Search for an existing target for this sdev.
325 list_for_each_entry(starget, &shost->__targets, siblings) {
326 if (starget->id == id &&
327 starget->channel == channel) {
328 found_starget = starget;
333 get_device(&found_starget->dev);
335 return found_starget;
339 * scsi_alloc_target - allocate a new or find an existing target
340 * @parent: parent of the target (need not be a scsi host)
341 * @channel: target channel number (zero if no channels)
342 * @id: target id number
344 * Return an existing target if one exists, provided it hasn't already
345 * gone into STARGET_DEL state, otherwise allocate a new target.
347 * The target is returned with an incremented reference, so the caller
348 * is responsible for both reaping and doing a last put
350 static struct scsi_target *scsi_alloc_target(struct device *parent,
351 int channel, uint id)
353 struct Scsi_Host *shost = dev_to_shost(parent);
354 struct device *dev = NULL;
356 const int size = sizeof(struct scsi_target)
357 + shost->transportt->target_size;
358 struct scsi_target *starget;
359 struct scsi_target *found_target;
362 starget = kzalloc(size, GFP_KERNEL);
364 printk(KERN_ERR "%s: allocation failure\n", __FUNCTION__);
368 device_initialize(dev);
369 starget->reap_ref = 1;
370 dev->parent = get_device(parent);
371 dev->release = scsi_target_dev_release;
372 sprintf(dev->bus_id, "target%d:%d:%d",
373 shost->host_no, channel, id);
375 starget->channel = channel;
376 INIT_LIST_HEAD(&starget->siblings);
377 INIT_LIST_HEAD(&starget->devices);
378 starget->state = STARGET_RUNNING;
380 spin_lock_irqsave(shost->host_lock, flags);
382 found_target = __scsi_find_target(parent, channel, id);
386 list_add_tail(&starget->siblings, &shost->__targets);
387 spin_unlock_irqrestore(shost->host_lock, flags);
388 /* allocate and add */
389 transport_setup_device(dev);
390 error = device_add(dev);
392 dev_err(dev, "target device_add failed, error %d\n", error);
393 spin_lock_irqsave(shost->host_lock, flags);
394 list_del_init(&starget->siblings);
395 spin_unlock_irqrestore(shost->host_lock, flags);
396 transport_destroy_device(dev);
401 transport_add_device(dev);
402 if (shost->hostt->target_alloc) {
403 error = shost->hostt->target_alloc(starget);
406 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
407 /* don't want scsi_target_reap to do the final
408 * put because it will be under the host lock */
410 scsi_target_reap(starget);
420 found_target->reap_ref++;
421 spin_unlock_irqrestore(shost->host_lock, flags);
422 if (found_target->state != STARGET_DEL) {
427 /* Unfortunately, we found a dying target; need to
428 * wait until it's dead before we can get a new one */
429 put_device(&found_target->dev);
430 flush_scheduled_work();
434 static void scsi_target_reap_usercontext(void *data)
436 struct scsi_target *starget = data;
437 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
440 transport_remove_device(&starget->dev);
441 device_del(&starget->dev);
442 transport_destroy_device(&starget->dev);
443 spin_lock_irqsave(shost->host_lock, flags);
444 if (shost->hostt->target_destroy)
445 shost->hostt->target_destroy(starget);
446 list_del_init(&starget->siblings);
447 spin_unlock_irqrestore(shost->host_lock, flags);
448 put_device(&starget->dev);
452 * scsi_target_reap - check to see if target is in use and destroy if not
454 * @starget: target to be checked
456 * This is used after removing a LUN or doing a last put of the target
457 * it checks atomically that nothing is using the target and removes
460 void scsi_target_reap(struct scsi_target *starget)
462 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
465 spin_lock_irqsave(shost->host_lock, flags);
467 if (--starget->reap_ref == 0 && list_empty(&starget->devices)) {
468 BUG_ON(starget->state == STARGET_DEL);
469 starget->state = STARGET_DEL;
470 spin_unlock_irqrestore(shost->host_lock, flags);
471 execute_in_process_context(scsi_target_reap_usercontext,
472 starget, &starget->ew);
476 spin_unlock_irqrestore(shost->host_lock, flags);
482 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string
483 * @s: INQUIRY result string to sanitize
484 * @len: length of the string
487 * The SCSI spec says that INQUIRY vendor, product, and revision
488 * strings must consist entirely of graphic ASCII characters,
489 * padded on the right with spaces. Since not all devices obey
490 * this rule, we will replace non-graphic or non-ASCII characters
491 * with spaces. Exception: a NUL character is interpreted as a
492 * string terminator, so all the following characters are set to
495 static void sanitize_inquiry_string(unsigned char *s, int len)
499 for (; len > 0; (--len, ++s)) {
502 if (terminated || *s < 0x20 || *s > 0x7e)
508 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
509 * @sdev: scsi_device to probe
510 * @inq_result: area to store the INQUIRY result
511 * @result_len: len of inq_result
512 * @bflags: store any bflags found here
515 * Probe the lun associated with @req using a standard SCSI INQUIRY;
517 * If the INQUIRY is successful, zero is returned and the
518 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
519 * are copied to the scsi_device any flags value is stored in *@bflags.
521 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
522 int result_len, int *bflags)
524 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
525 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
526 int response_len = 0;
527 int pass, count, result;
528 struct scsi_sense_hdr sshdr;
532 /* Perform up to 3 passes. The first pass uses a conservative
533 * transfer length of 36 unless sdev->inquiry_len specifies a
534 * different value. */
535 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
536 try_inquiry_len = first_inquiry_len;
540 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
541 "scsi scan: INQUIRY pass %d length %d\n",
542 pass, try_inquiry_len));
544 /* Each pass gets up to three chances to ignore Unit Attention */
545 for (count = 0; count < 3; ++count) {
546 memset(scsi_cmd, 0, 6);
547 scsi_cmd[0] = INQUIRY;
548 scsi_cmd[4] = (unsigned char) try_inquiry_len;
550 memset(inq_result, 0, try_inquiry_len);
552 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
553 inq_result, try_inquiry_len, &sshdr,
554 HZ / 2 + HZ * scsi_inq_timeout, 3);
556 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s "
558 result ? "failed" : "successful", result));
562 * not-ready to ready transition [asc/ascq=0x28/0x0]
563 * or power-on, reset [asc/ascq=0x29/0x0], continue.
564 * INQUIRY should not yield UNIT_ATTENTION
565 * but many buggy devices do so anyway.
567 if ((driver_byte(result) & DRIVER_SENSE) &&
568 scsi_sense_valid(&sshdr)) {
569 if ((sshdr.sense_key == UNIT_ATTENTION) &&
570 ((sshdr.asc == 0x28) ||
571 (sshdr.asc == 0x29)) &&
580 sanitize_inquiry_string(&inq_result[8], 8);
581 sanitize_inquiry_string(&inq_result[16], 16);
582 sanitize_inquiry_string(&inq_result[32], 4);
584 response_len = inq_result[4] + 5;
585 if (response_len > 255)
586 response_len = first_inquiry_len; /* sanity */
589 * Get any flags for this device.
591 * XXX add a bflags to scsi_device, and replace the
592 * corresponding bit fields in scsi_device, so bflags
593 * need not be passed as an argument.
595 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
598 /* When the first pass succeeds we gain information about
599 * what larger transfer lengths might work. */
601 if (BLIST_INQUIRY_36 & *bflags)
602 next_inquiry_len = 36;
603 else if (BLIST_INQUIRY_58 & *bflags)
604 next_inquiry_len = 58;
605 else if (sdev->inquiry_len)
606 next_inquiry_len = sdev->inquiry_len;
608 next_inquiry_len = response_len;
610 /* If more data is available perform the second pass */
611 if (next_inquiry_len > try_inquiry_len) {
612 try_inquiry_len = next_inquiry_len;
618 } else if (pass == 2) {
619 printk(KERN_INFO "scsi scan: %d byte inquiry failed. "
620 "Consider BLIST_INQUIRY_36 for this device\n",
623 /* If this pass failed, the third pass goes back and transfers
624 * the same amount as we successfully got in the first pass. */
625 try_inquiry_len = first_inquiry_len;
630 /* If the last transfer attempt got an error, assume the
631 * peripheral doesn't exist or is dead. */
635 /* Don't report any more data than the device says is valid */
636 sdev->inquiry_len = min(try_inquiry_len, response_len);
639 * XXX Abort if the response length is less than 36? If less than
640 * 32, the lookup of the device flags (above) could be invalid,
641 * and it would be possible to take an incorrect action - we do
642 * not want to hang because of a short INQUIRY. On the flip side,
643 * if the device is spun down or becoming ready (and so it gives a
644 * short INQUIRY), an abort here prevents any further use of the
645 * device, including spin up.
647 * Related to the above issue:
649 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
650 * and if not ready, sent a START_STOP to start (maybe spin up) and
651 * then send the INQUIRY again, since the INQUIRY can change after
652 * a device is initialized.
654 * Ideally, start a device if explicitly asked to do so. This
655 * assumes that a device is spun up on power on, spun down on
656 * request, and then spun up on request.
660 * The scanning code needs to know the scsi_level, even if no
661 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
662 * non-zero LUNs can be scanned.
664 sdev->scsi_level = inq_result[2] & 0x07;
665 if (sdev->scsi_level >= 2 ||
666 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
668 sdev->sdev_target->scsi_level = sdev->scsi_level;
674 * scsi_add_lun - allocate and fully initialze a scsi_device
675 * @sdevscan: holds information to be stored in the new scsi_device
676 * @sdevnew: store the address of the newly allocated scsi_device
677 * @inq_result: holds the result of a previous INQUIRY to the LUN
678 * @bflags: black/white list flag
681 * Allocate and initialize a scsi_device matching sdevscan. Optionally
682 * set fields based on values in *@bflags. If @sdevnew is not
683 * NULL, store the address of the new scsi_device in *@sdevnew (needed
684 * when scanning a particular LUN).
687 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
688 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
690 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
691 int *bflags, int async)
694 * XXX do not save the inquiry, since it can change underneath us,
695 * save just vendor/model/rev.
697 * Rather than save it and have an ioctl that retrieves the saved
698 * value, have an ioctl that executes the same INQUIRY code used
699 * in scsi_probe_lun, let user level programs doing INQUIRY
700 * scanning run at their own risk, or supply a user level program
701 * that can correctly scan.
705 * Copy at least 36 bytes of INQUIRY data, so that we don't
706 * dereference unallocated memory when accessing the Vendor,
707 * Product, and Revision strings. Badly behaved devices may set
708 * the INQUIRY Additional Length byte to a small value, indicating
709 * these strings are invalid, but often they contain plausible data
710 * nonetheless. It doesn't matter if the device sent < 36 bytes
711 * total, since scsi_probe_lun() initializes inq_result with 0s.
713 sdev->inquiry = kmemdup(inq_result,
714 max_t(size_t, sdev->inquiry_len, 36),
716 if (sdev->inquiry == NULL)
717 return SCSI_SCAN_NO_RESPONSE;
719 sdev->vendor = (char *) (sdev->inquiry + 8);
720 sdev->model = (char *) (sdev->inquiry + 16);
721 sdev->rev = (char *) (sdev->inquiry + 32);
723 if (*bflags & BLIST_ISROM) {
725 * It would be better to modify sdev->type, and set
726 * sdev->removable; this can now be done since
727 * print_inquiry has gone away.
729 inq_result[0] = TYPE_ROM;
730 inq_result[1] |= 0x80; /* removable */
731 } else if (*bflags & BLIST_NO_ULD_ATTACH)
732 sdev->no_uld_attach = 1;
734 switch (sdev->type = (inq_result[0] & 0x1f)) {
741 case TYPE_MEDIUM_CHANGER:
753 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
757 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
758 * spec says: The device server is capable of supporting the
759 * specified peripheral device type on this logical unit. However,
760 * the physical device is not currently connected to this logical
763 * The above is vague, as it implies that we could treat 001 and
764 * 011 the same. Stay compatible with previous code, and create a
765 * scsi_device for a PQ of 1
767 * Don't set the device offline here; rather let the upper
768 * level drivers eval the PQ to decide whether they should
769 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
772 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
773 sdev->removable = (0x80 & inq_result[1]) >> 7;
774 sdev->lockable = sdev->removable;
775 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
777 if (sdev->scsi_level >= SCSI_3 || (sdev->inquiry_len > 56 &&
778 inq_result[56] & 0x04))
780 if (inq_result[7] & 0x60)
782 if (inq_result[7] & 0x10)
785 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
786 "ANSI: %d%s\n", scsi_device_type(sdev->type),
787 sdev->vendor, sdev->model, sdev->rev,
788 sdev->inq_periph_qual, inq_result[2] & 0x07,
789 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
795 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
796 !(*bflags & BLIST_NOTQ))
797 sdev->tagged_supported = 1;
799 * Some devices (Texel CD ROM drives) have handshaking problems
800 * when used with the Seagate controllers. borken is initialized
801 * to 1, and then set it to 0 here.
803 if ((*bflags & BLIST_BORKEN) == 0)
807 * Apparently some really broken devices (contrary to the SCSI
808 * standards) need to be selected without asserting ATN
810 if (*bflags & BLIST_SELECT_NO_ATN)
811 sdev->select_no_atn = 1;
814 * Maximum 512 sector transfer length
815 * broken RA4x00 Compaq Disk Array
817 if (*bflags & BLIST_MAX_512)
818 blk_queue_max_sectors(sdev->request_queue, 512);
821 * Some devices may not want to have a start command automatically
822 * issued when a device is added.
824 if (*bflags & BLIST_NOSTARTONADD)
825 sdev->no_start_on_add = 1;
827 if (*bflags & BLIST_SINGLELUN)
828 sdev->single_lun = 1;
831 sdev->use_10_for_rw = 1;
833 if (*bflags & BLIST_MS_SKIP_PAGE_08)
834 sdev->skip_ms_page_8 = 1;
836 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
837 sdev->skip_ms_page_3f = 1;
839 if (*bflags & BLIST_USE_10_BYTE_MS)
840 sdev->use_10_for_ms = 1;
842 /* set the device running here so that slave configure
844 scsi_device_set_state(sdev, SDEV_RUNNING);
846 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
847 sdev->use_192_bytes_for_3f = 1;
849 if (*bflags & BLIST_NOT_LOCKABLE)
852 if (*bflags & BLIST_RETRY_HWERROR)
853 sdev->retry_hwerror = 1;
855 transport_configure_device(&sdev->sdev_gendev);
857 if (sdev->host->hostt->slave_configure) {
858 int ret = sdev->host->hostt->slave_configure(sdev);
861 * if LLDD reports slave not present, don't clutter
862 * console with alloc failure messages
865 sdev_printk(KERN_ERR, sdev,
866 "failed to configure device\n");
868 return SCSI_SCAN_NO_RESPONSE;
873 * Ok, the device is now all set up, we can
874 * register it and tell the rest of the kernel
877 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
878 return SCSI_SCAN_NO_RESPONSE;
880 return SCSI_SCAN_LUN_PRESENT;
883 static inline void scsi_destroy_sdev(struct scsi_device *sdev)
885 scsi_device_set_state(sdev, SDEV_DEL);
886 if (sdev->host->hostt->slave_destroy)
887 sdev->host->hostt->slave_destroy(sdev);
888 transport_destroy_device(&sdev->sdev_gendev);
889 put_device(&sdev->sdev_gendev);
892 #ifdef CONFIG_SCSI_LOGGING
894 * scsi_inq_str - print INQUIRY data from min to max index,
895 * strip trailing whitespace
896 * @buf: Output buffer with at least end-first+1 bytes of space
897 * @inq: Inquiry buffer (input)
898 * @first: Offset of string into inq
899 * @end: Index after last character in inq
901 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
902 unsigned first, unsigned end)
904 unsigned term = 0, idx;
906 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
907 if (inq[idx+first] > ' ') {
908 buf[idx] = inq[idx+first];
920 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
921 * @starget: pointer to target device structure
922 * @lun: LUN of target device
923 * @sdevscan: probe the LUN corresponding to this scsi_device
924 * @sdevnew: store the value of any new scsi_device allocated
925 * @bflagsp: store bflags here if not NULL
928 * Call scsi_probe_lun, if a LUN with an attached device is found,
929 * allocate and set it up by calling scsi_add_lun.
932 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
933 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
934 * attached at the LUN
935 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
937 static int scsi_probe_and_add_lun(struct scsi_target *starget,
938 uint lun, int *bflagsp,
939 struct scsi_device **sdevp, int rescan,
942 struct scsi_device *sdev;
943 unsigned char *result;
944 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
945 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
948 * The rescan flag is used as an optimization, the first scan of a
949 * host adapter calls into here with rescan == 0.
951 sdev = scsi_device_lookup_by_target(starget, lun);
953 if (rescan || sdev->sdev_state != SDEV_CREATED) {
954 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
955 "scsi scan: device exists on %s\n",
956 sdev->sdev_gendev.bus_id));
960 scsi_device_put(sdev);
963 *bflagsp = scsi_get_device_flags(sdev,
966 return SCSI_SCAN_LUN_PRESENT;
968 scsi_device_put(sdev);
970 sdev = scsi_alloc_sdev(starget, lun, hostdata);
974 result = kmalloc(result_len, GFP_ATOMIC |
975 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
979 if (scsi_probe_lun(sdev, result, result_len, &bflags))
980 goto out_free_result;
985 * result contains valid SCSI INQUIRY data.
987 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
989 * For a Peripheral qualifier 3 (011b), the SCSI
990 * spec says: The device server is not capable of
991 * supporting a physical device on this logical
994 * For disks, this implies that there is no
995 * logical disk configured at sdev->lun, but there
996 * is a target id responding.
998 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
999 " peripheral qualifier of 3, device not"
1002 SCSI_LOG_SCAN_BUS(1, {
1003 unsigned char vend[9];
1004 unsigned char mod[17];
1006 sdev_printk(KERN_INFO, sdev,
1007 "scsi scan: consider passing scsi_mod."
1008 "dev_flags=%s:%s:0x240 or 0x800240\n",
1009 scsi_inq_str(vend, result, 8, 16),
1010 scsi_inq_str(mod, result, 16, 32));
1014 res = SCSI_SCAN_TARGET_PRESENT;
1015 goto out_free_result;
1019 * Some targets may set slight variations of PQ and PDT to signal
1020 * that no LUN is present, so don't add sdev in these cases.
1021 * Two specific examples are:
1022 * 1) NetApp targets: return PQ=1, PDT=0x1f
1023 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1024 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1027 * 1) SCSI SPC-3, pp. 145-146
1028 * PQ=1: "A peripheral device having the specified peripheral
1029 * device type is not connected to this logical unit. However, the
1030 * device server is capable of supporting the specified peripheral
1031 * device type on this logical unit."
1032 * PDT=0x1f: "Unknown or no device type"
1033 * 2) USB UFI 1.0, p. 20
1034 * PDT=00h Direct-access device (floppy)
1035 * PDT=1Fh none (no FDD connected to the requested logical unit)
1037 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1038 (result[0] & 0x1f) == 0x1f) {
1039 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1040 "scsi scan: peripheral device type"
1041 " of 31, no device added\n"));
1042 res = SCSI_SCAN_TARGET_PRESENT;
1043 goto out_free_result;
1046 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1047 if (res == SCSI_SCAN_LUN_PRESENT) {
1048 if (bflags & BLIST_KEY) {
1050 scsi_unlock_floptical(sdev, result);
1057 if (res == SCSI_SCAN_LUN_PRESENT) {
1059 if (scsi_device_get(sdev) == 0) {
1062 __scsi_remove_device(sdev);
1063 res = SCSI_SCAN_NO_RESPONSE;
1067 scsi_destroy_sdev(sdev);
1073 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1074 * @starget: pointer to target structure to scan
1075 * @bflags: black/white list flag for LUN 0
1078 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1079 * scanned) to some maximum lun until a LUN is found with no device
1080 * attached. Use the bflags to figure out any oddities.
1082 * Modifies sdevscan->lun.
1084 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1085 int bflags, int scsi_level, int rescan)
1087 unsigned int sparse_lun, lun, max_dev_lun;
1088 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1090 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
1091 "%s\n", starget->dev.bus_id));
1093 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1095 * If this device is known to support sparse multiple units,
1096 * override the other settings, and scan all of them. Normally,
1097 * SCSI-3 devices should be scanned via the REPORT LUNS.
1099 if (bflags & BLIST_SPARSELUN) {
1100 max_dev_lun = shost->max_lun;
1106 * If less than SCSI_1_CSS, and no special lun scaning, stop
1107 * scanning; this matches 2.4 behaviour, but could just be a bug
1108 * (to continue scanning a SCSI_1_CSS device).
1110 * This test is broken. We might not have any device on lun0 for
1111 * a sparselun device, and if that's the case then how would we
1112 * know the real scsi_level, eh? It might make sense to just not
1113 * scan any SCSI_1 device for non-0 luns, but that check would best
1114 * go into scsi_alloc_sdev() and just have it return null when asked
1115 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1117 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1118 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1123 * If this device is known to support multiple units, override
1124 * the other settings, and scan all of them.
1126 if (bflags & BLIST_FORCELUN)
1127 max_dev_lun = shost->max_lun;
1129 * REGAL CDC-4X: avoid hang after LUN 4
1131 if (bflags & BLIST_MAX5LUN)
1132 max_dev_lun = min(5U, max_dev_lun);
1134 * Do not scan SCSI-2 or lower device past LUN 7, unless
1137 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1138 max_dev_lun = min(8U, max_dev_lun);
1141 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1142 * until we reach the max, or no LUN is found and we are not
1145 for (lun = 1; lun < max_dev_lun; ++lun)
1146 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1147 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1153 * scsilun_to_int: convert a scsi_lun to an int
1154 * @scsilun: struct scsi_lun to be converted.
1157 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
1158 * integer, and return the result. The caller must check for
1159 * truncation before using this function.
1162 * The struct scsi_lun is assumed to be four levels, with each level
1163 * effectively containing a SCSI byte-ordered (big endian) short; the
1164 * addressing bits of each level are ignored (the highest two bits).
1165 * For a description of the LUN format, post SCSI-3 see the SCSI
1166 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
1168 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
1169 * the integer: 0x0b030a04
1171 static int scsilun_to_int(struct scsi_lun *scsilun)
1177 for (i = 0; i < sizeof(lun); i += 2)
1178 lun = lun | (((scsilun->scsi_lun[i] << 8) |
1179 scsilun->scsi_lun[i + 1]) << (i * 8));
1184 * int_to_scsilun: reverts an int into a scsi_lun
1185 * @int: integer to be reverted
1186 * @scsilun: struct scsi_lun to be set.
1189 * Reverts the functionality of the scsilun_to_int, which packed
1190 * an 8-byte lun value into an int. This routine unpacks the int
1191 * back into the lun value.
1192 * Note: the scsilun_to_int() routine does not truly handle all
1193 * 8bytes of the lun value. This functions restores only as much
1194 * as was set by the routine.
1197 * Given an integer : 0x0b030a04, this function returns a
1198 * scsi_lun of : struct scsi_lun of: 0a 04 0b 03 00 00 00 00
1201 void int_to_scsilun(unsigned int lun, struct scsi_lun *scsilun)
1205 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
1207 for (i = 0; i < sizeof(lun); i += 2) {
1208 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
1209 scsilun->scsi_lun[i+1] = lun & 0xFF;
1213 EXPORT_SYMBOL(int_to_scsilun);
1216 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1217 * @sdevscan: scan the host, channel, and id of this scsi_device
1220 * If @sdevscan is for a SCSI-3 or up device, send a REPORT LUN
1221 * command, and scan the resulting list of LUNs by calling
1222 * scsi_probe_and_add_lun.
1224 * Modifies sdevscan->lun.
1227 * 0: scan completed (or no memory, so further scanning is futile)
1228 * 1: no report lun scan, or not configured
1230 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1234 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1235 unsigned int length;
1237 unsigned int num_luns;
1238 unsigned int retries;
1240 struct scsi_lun *lunp, *lun_data;
1242 struct scsi_sense_hdr sshdr;
1243 struct scsi_device *sdev;
1244 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1248 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1249 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1250 * support more than 8 LUNs.
1252 if (bflags & BLIST_NOREPORTLUN)
1254 if (starget->scsi_level < SCSI_2 &&
1255 starget->scsi_level != SCSI_UNKNOWN)
1257 if (starget->scsi_level < SCSI_3 &&
1258 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1260 if (bflags & BLIST_NOLUN)
1263 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1264 sdev = scsi_alloc_sdev(starget, 0, NULL);
1267 if (scsi_device_get(sdev))
1271 sprintf(devname, "host %d channel %d id %d",
1272 shost->host_no, sdev->channel, sdev->id);
1275 * Allocate enough to hold the header (the same size as one scsi_lun)
1276 * plus the max number of luns we are requesting.
1278 * Reallocating and trying again (with the exact amount we need)
1279 * would be nice, but then we need to somehow limit the size
1280 * allocated based on the available memory and the limits of
1281 * kmalloc - we don't want a kmalloc() failure of a huge value to
1282 * prevent us from finding any LUNs on this target.
1284 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
1285 lun_data = kmalloc(length, GFP_ATOMIC |
1286 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1288 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
1292 scsi_cmd[0] = REPORT_LUNS;
1295 * bytes 1 - 5: reserved, set to zero.
1297 memset(&scsi_cmd[1], 0, 5);
1300 * bytes 6 - 9: length of the command.
1302 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
1303 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
1304 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
1305 scsi_cmd[9] = (unsigned char) length & 0xff;
1307 scsi_cmd[10] = 0; /* reserved */
1308 scsi_cmd[11] = 0; /* control */
1311 * We can get a UNIT ATTENTION, for example a power on/reset, so
1312 * retry a few times (like sd.c does for TEST UNIT READY).
1313 * Experience shows some combinations of adapter/devices get at
1314 * least two power on/resets.
1316 * Illegal requests (for devices that do not support REPORT LUNS)
1317 * should come through as a check condition, and will not generate
1320 for (retries = 0; retries < 3; retries++) {
1321 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
1322 " REPORT LUNS to %s (try %d)\n", devname,
1325 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1326 lun_data, length, &sshdr,
1327 SCSI_TIMEOUT + 4 * HZ, 3);
1329 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
1330 " %s (try %d) result 0x%x\n", result
1331 ? "failed" : "successful", retries, result));
1334 else if (scsi_sense_valid(&sshdr)) {
1335 if (sshdr.sense_key != UNIT_ATTENTION)
1342 * The device probably does not support a REPORT LUN command
1349 * Get the length from the first four bytes of lun_data.
1351 data = (u8 *) lun_data->scsi_lun;
1352 length = ((data[0] << 24) | (data[1] << 16) |
1353 (data[2] << 8) | (data[3] << 0));
1355 num_luns = (length / sizeof(struct scsi_lun));
1356 if (num_luns > max_scsi_report_luns) {
1357 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1358 " of %d luns reported, try increasing"
1359 " max_scsi_report_luns.\n", devname,
1360 max_scsi_report_luns, num_luns);
1361 num_luns = max_scsi_report_luns;
1364 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1365 "scsi scan: REPORT LUN scan\n"));
1368 * Scan the luns in lun_data. The entry at offset 0 is really
1369 * the header, so start at 1 and go up to and including num_luns.
1371 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1372 lun = scsilun_to_int(lunp);
1375 * Check if the unused part of lunp is non-zero, and so
1376 * does not fit in lun.
1378 if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) {
1382 * Output an error displaying the LUN in byte order,
1383 * this differs from what linux would print for the
1384 * integer LUN value.
1386 printk(KERN_WARNING "scsi: %s lun 0x", devname);
1387 data = (char *)lunp->scsi_lun;
1388 for (i = 0; i < sizeof(struct scsi_lun); i++)
1389 printk("%02x", data[i]);
1390 printk(" has a LUN larger than currently supported.\n");
1391 } else if (lun > sdev->host->max_lun) {
1392 printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
1393 " than allowed by the host adapter\n",
1398 res = scsi_probe_and_add_lun(starget,
1399 lun, NULL, NULL, rescan, NULL);
1400 if (res == SCSI_SCAN_NO_RESPONSE) {
1402 * Got some results, but now none, abort.
1404 sdev_printk(KERN_ERR, sdev,
1405 "Unexpected response"
1406 " from lun %d while scanning, scan"
1416 scsi_device_put(sdev);
1417 if (sdev->sdev_state == SDEV_CREATED)
1419 * the sdev we used didn't appear in the report luns scan
1421 scsi_destroy_sdev(sdev);
1425 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1426 uint id, uint lun, void *hostdata)
1428 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1429 struct device *parent = &shost->shost_gendev;
1430 struct scsi_target *starget;
1432 starget = scsi_alloc_target(parent, channel, id);
1434 return ERR_PTR(-ENOMEM);
1436 mutex_lock(&shost->scan_mutex);
1437 if (scsi_host_scan_allowed(shost))
1438 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1439 mutex_unlock(&shost->scan_mutex);
1440 scsi_target_reap(starget);
1441 put_device(&starget->dev);
1445 EXPORT_SYMBOL(__scsi_add_device);
1447 int scsi_add_device(struct Scsi_Host *host, uint channel,
1448 uint target, uint lun)
1450 struct scsi_device *sdev =
1451 __scsi_add_device(host, channel, target, lun, NULL);
1453 return PTR_ERR(sdev);
1455 scsi_device_put(sdev);
1458 EXPORT_SYMBOL(scsi_add_device);
1460 void scsi_rescan_device(struct device *dev)
1462 struct scsi_driver *drv;
1467 drv = to_scsi_driver(dev->driver);
1468 if (try_module_get(drv->owner)) {
1471 module_put(drv->owner);
1474 EXPORT_SYMBOL(scsi_rescan_device);
1476 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1477 unsigned int id, unsigned int lun, int rescan)
1479 struct Scsi_Host *shost = dev_to_shost(parent);
1482 struct scsi_target *starget;
1484 if (shost->this_id == id)
1486 * Don't scan the host adapter
1490 starget = scsi_alloc_target(parent, channel, id);
1494 if (lun != SCAN_WILD_CARD) {
1496 * Scan for a specific host/chan/id/lun.
1498 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1503 * Scan LUN 0, if there is some response, scan further. Ideally, we
1504 * would not configure LUN 0 until all LUNs are scanned.
1506 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1507 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1508 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1510 * The REPORT LUN did not scan the target,
1511 * do a sequential scan.
1513 scsi_sequential_lun_scan(starget, bflags,
1514 starget->scsi_level, rescan);
1518 /* now determine if the target has any children at all
1519 * and if not, nuke it */
1520 scsi_target_reap(starget);
1522 put_device(&starget->dev);
1526 * scsi_scan_target - scan a target id, possibly including all LUNs on the
1528 * @parent: host to scan
1529 * @channel: channel to scan
1530 * @id: target id to scan
1531 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1532 * @rescan: passed to LUN scanning routines
1535 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1536 * and possibly all LUNs on the target id.
1538 * First try a REPORT LUN scan, if that does not scan the target, do a
1539 * sequential scan of LUNs on the target id.
1541 void scsi_scan_target(struct device *parent, unsigned int channel,
1542 unsigned int id, unsigned int lun, int rescan)
1544 struct Scsi_Host *shost = dev_to_shost(parent);
1546 if (!shost->async_scan)
1547 scsi_complete_async_scans();
1549 mutex_lock(&shost->scan_mutex);
1550 if (scsi_host_scan_allowed(shost))
1551 __scsi_scan_target(parent, channel, id, lun, rescan);
1552 mutex_unlock(&shost->scan_mutex);
1554 EXPORT_SYMBOL(scsi_scan_target);
1556 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1557 unsigned int id, unsigned int lun, int rescan)
1561 if (id == SCAN_WILD_CARD)
1562 for (id = 0; id < shost->max_id; ++id) {
1564 * XXX adapter drivers when possible (FCP, iSCSI)
1565 * could modify max_id to match the current max,
1566 * not the absolute max.
1568 * XXX add a shost id iterator, so for example,
1569 * the FC ID can be the same as a target id
1570 * without a huge overhead of sparse id's.
1572 if (shost->reverse_ordering)
1574 * Scan from high to low id.
1576 order_id = shost->max_id - id - 1;
1579 __scsi_scan_target(&shost->shost_gendev, channel,
1580 order_id, lun, rescan);
1583 __scsi_scan_target(&shost->shost_gendev, channel,
1587 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1588 unsigned int id, unsigned int lun, int rescan)
1590 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1592 __FUNCTION__, channel, id, lun));
1594 if (!shost->async_scan)
1595 scsi_complete_async_scans();
1597 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1598 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1599 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1602 mutex_lock(&shost->scan_mutex);
1603 if (scsi_host_scan_allowed(shost)) {
1604 if (channel == SCAN_WILD_CARD)
1605 for (channel = 0; channel <= shost->max_channel;
1607 scsi_scan_channel(shost, channel, id, lun,
1610 scsi_scan_channel(shost, channel, id, lun, rescan);
1612 mutex_unlock(&shost->scan_mutex);
1617 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1619 struct scsi_device *sdev;
1620 shost_for_each_device(sdev, shost) {
1621 if (scsi_sysfs_add_sdev(sdev) != 0)
1622 scsi_destroy_sdev(sdev);
1627 * scsi_prep_async_scan - prepare for an async scan
1628 * @shost: the host which will be scanned
1629 * Returns: a cookie to be passed to scsi_finish_async_scan()
1631 * Tells the midlayer this host is going to do an asynchronous scan.
1632 * It reserves the host's position in the scanning list and ensures
1633 * that other asynchronous scans started after this one won't affect the
1634 * ordering of the discovered devices.
1636 struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1638 struct async_scan_data *data;
1640 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1643 if (shost->async_scan) {
1644 printk("%s called twice for host %d", __FUNCTION__,
1650 data = kmalloc(sizeof(*data), GFP_KERNEL);
1653 data->shost = scsi_host_get(shost);
1656 init_completion(&data->prev_finished);
1658 spin_lock(&async_scan_lock);
1659 shost->async_scan = 1;
1660 if (list_empty(&scanning_hosts))
1661 complete(&data->prev_finished);
1662 list_add_tail(&data->list, &scanning_hosts);
1663 spin_unlock(&async_scan_lock);
1673 * scsi_finish_async_scan - asynchronous scan has finished
1674 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1676 * All the devices currently attached to this host have been found.
1677 * This function announces all the devices it has found to the rest
1680 void scsi_finish_async_scan(struct async_scan_data *data)
1682 struct Scsi_Host *shost;
1687 shost = data->shost;
1688 if (!shost->async_scan) {
1689 printk("%s called twice for host %d", __FUNCTION__,
1695 wait_for_completion(&data->prev_finished);
1697 scsi_sysfs_add_devices(shost);
1699 spin_lock(&async_scan_lock);
1700 shost->async_scan = 0;
1701 list_del(&data->list);
1702 if (!list_empty(&scanning_hosts)) {
1703 struct async_scan_data *next = list_entry(scanning_hosts.next,
1704 struct async_scan_data, list);
1705 complete(&next->prev_finished);
1707 spin_unlock(&async_scan_lock);
1709 scsi_host_put(shost);
1713 static int do_scan_async(void *_data)
1715 struct async_scan_data *data = _data;
1716 scsi_scan_host_selected(data->shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1719 scsi_finish_async_scan(data);
1724 * scsi_scan_host - scan the given adapter
1725 * @shost: adapter to scan
1727 void scsi_scan_host(struct Scsi_Host *shost)
1729 struct async_scan_data *data;
1731 if (strncmp(scsi_scan_type, "none", 4) == 0)
1734 data = scsi_prep_async_scan(shost);
1736 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1740 kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no);
1742 EXPORT_SYMBOL(scsi_scan_host);
1744 void scsi_forget_host(struct Scsi_Host *shost)
1746 struct scsi_device *sdev;
1747 unsigned long flags;
1750 spin_lock_irqsave(shost->host_lock, flags);
1751 list_for_each_entry(sdev, &shost->__devices, siblings) {
1752 if (sdev->sdev_state == SDEV_DEL)
1754 spin_unlock_irqrestore(shost->host_lock, flags);
1755 __scsi_remove_device(sdev);
1758 spin_unlock_irqrestore(shost->host_lock, flags);
1762 * Function: scsi_get_host_dev()
1764 * Purpose: Create a scsi_device that points to the host adapter itself.
1766 * Arguments: SHpnt - Host that needs a scsi_device
1768 * Lock status: None assumed.
1770 * Returns: The scsi_device or NULL
1773 * Attach a single scsi_device to the Scsi_Host - this should
1774 * be made to look like a "pseudo-device" that points to the
1777 * Note - this device is not accessible from any high-level
1778 * drivers (including generics), which is probably not
1779 * optimal. We can add hooks later to attach
1781 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1783 struct scsi_device *sdev = NULL;
1784 struct scsi_target *starget;
1786 mutex_lock(&shost->scan_mutex);
1787 if (!scsi_host_scan_allowed(shost))
1789 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1793 sdev = scsi_alloc_sdev(starget, 0, NULL);
1795 sdev->sdev_gendev.parent = get_device(&starget->dev);
1798 scsi_target_reap(starget);
1799 put_device(&starget->dev);
1801 mutex_unlock(&shost->scan_mutex);
1804 EXPORT_SYMBOL(scsi_get_host_dev);
1807 * Function: scsi_free_host_dev()
1809 * Purpose: Free a scsi_device that points to the host adapter itself.
1811 * Arguments: SHpnt - Host that needs a scsi_device
1813 * Lock status: None assumed.
1819 void scsi_free_host_dev(struct scsi_device *sdev)
1821 BUG_ON(sdev->id != sdev->host->this_id);
1823 scsi_destroy_sdev(sdev);
1825 EXPORT_SYMBOL(scsi_free_host_dev);