Staging: strip: delete the driver
[linux/fpc-iii.git] / drivers / scsi / scsi_scan.c
blob38518b0880739a5d2dded941e5b6cfbdb85c131d
1 /*
2 * scsi_scan.c
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
20 * scsi_device for it.
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"
54 * Default timeout
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
71 * on the given LUN.
73 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
74 * given LUN.
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 #ifdef CONFIG_SCSI_MULTI_LUN
85 static unsigned int max_scsi_luns = MAX_SCSI_LUNS;
86 #else
87 static unsigned int max_scsi_luns = 1;
88 #endif
90 module_param_named(max_luns, max_scsi_luns, uint, S_IRUGO|S_IWUSR);
91 MODULE_PARM_DESC(max_luns,
92 "last scsi LUN (should be between 1 and 2^32-1)");
94 #ifdef CONFIG_SCSI_SCAN_ASYNC
95 #define SCSI_SCAN_TYPE_DEFAULT "async"
96 #else
97 #define SCSI_SCAN_TYPE_DEFAULT "sync"
98 #endif
100 static char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT;
102 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
103 MODULE_PARM_DESC(scan, "sync, async or none");
106 * max_scsi_report_luns: the maximum number of LUNS that will be
107 * returned from the REPORT LUNS command. 8 times this value must
108 * be allocated. In theory this could be up to an 8 byte value, but
109 * in practice, the maximum number of LUNs suppored by any device
110 * is about 16k.
112 static unsigned int max_scsi_report_luns = 511;
114 module_param_named(max_report_luns, max_scsi_report_luns, uint, S_IRUGO|S_IWUSR);
115 MODULE_PARM_DESC(max_report_luns,
116 "REPORT LUNS maximum number of LUNS received (should be"
117 " between 1 and 16384)");
119 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
121 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
122 MODULE_PARM_DESC(inq_timeout,
123 "Timeout (in seconds) waiting for devices to answer INQUIRY."
124 " Default is 20. Some devices may need more; most need less.");
126 /* This lock protects only this list */
127 static DEFINE_SPINLOCK(async_scan_lock);
128 static LIST_HEAD(scanning_hosts);
130 struct async_scan_data {
131 struct list_head list;
132 struct Scsi_Host *shost;
133 struct completion prev_finished;
137 * scsi_complete_async_scans - Wait for asynchronous scans to complete
139 * When this function returns, any host which started scanning before
140 * this function was called will have finished its scan. Hosts which
141 * started scanning after this function was called may or may not have
142 * finished.
144 int scsi_complete_async_scans(void)
146 struct async_scan_data *data;
148 do {
149 if (list_empty(&scanning_hosts))
150 return 0;
151 /* If we can't get memory immediately, that's OK. Just
152 * sleep a little. Even if we never get memory, the async
153 * scans will finish eventually.
155 data = kmalloc(sizeof(*data), GFP_KERNEL);
156 if (!data)
157 msleep(1);
158 } while (!data);
160 data->shost = NULL;
161 init_completion(&data->prev_finished);
163 spin_lock(&async_scan_lock);
164 /* Check that there's still somebody else on the list */
165 if (list_empty(&scanning_hosts))
166 goto done;
167 list_add_tail(&data->list, &scanning_hosts);
168 spin_unlock(&async_scan_lock);
170 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
171 wait_for_completion(&data->prev_finished);
173 spin_lock(&async_scan_lock);
174 list_del(&data->list);
175 if (!list_empty(&scanning_hosts)) {
176 struct async_scan_data *next = list_entry(scanning_hosts.next,
177 struct async_scan_data, list);
178 complete(&next->prev_finished);
180 done:
181 spin_unlock(&async_scan_lock);
183 kfree(data);
184 return 0;
187 /* Only exported for the benefit of scsi_wait_scan */
188 EXPORT_SYMBOL_GPL(scsi_complete_async_scans);
190 #ifndef MODULE
192 * For async scanning we need to wait for all the scans to complete before
193 * trying to mount the root fs. Otherwise non-modular drivers may not be ready
194 * yet.
196 late_initcall(scsi_complete_async_scans);
197 #endif
200 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
201 * @sdev: scsi device to send command to
202 * @result: area to store the result of the MODE SENSE
204 * Description:
205 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
206 * Called for BLIST_KEY devices.
208 static void scsi_unlock_floptical(struct scsi_device *sdev,
209 unsigned char *result)
211 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
213 printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
214 scsi_cmd[0] = MODE_SENSE;
215 scsi_cmd[1] = 0;
216 scsi_cmd[2] = 0x2e;
217 scsi_cmd[3] = 0;
218 scsi_cmd[4] = 0x2a; /* size */
219 scsi_cmd[5] = 0;
220 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
221 SCSI_TIMEOUT, 3, NULL);
225 * scsi_alloc_sdev - allocate and setup a scsi_Device
226 * @starget: which target to allocate a &scsi_device for
227 * @lun: which lun
228 * @hostdata: usually NULL and set by ->slave_alloc instead
230 * Description:
231 * Allocate, initialize for io, and return a pointer to a scsi_Device.
232 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
233 * adds scsi_Device to the appropriate list.
235 * Return value:
236 * scsi_Device pointer, or NULL on failure.
238 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
239 unsigned int lun, void *hostdata)
241 struct scsi_device *sdev;
242 int display_failure_msg = 1, ret;
243 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
244 extern void scsi_evt_thread(struct work_struct *work);
246 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
247 GFP_ATOMIC);
248 if (!sdev)
249 goto out;
251 sdev->vendor = scsi_null_device_strs;
252 sdev->model = scsi_null_device_strs;
253 sdev->rev = scsi_null_device_strs;
254 sdev->host = shost;
255 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
256 sdev->id = starget->id;
257 sdev->lun = lun;
258 sdev->channel = starget->channel;
259 sdev->sdev_state = SDEV_CREATED;
260 INIT_LIST_HEAD(&sdev->siblings);
261 INIT_LIST_HEAD(&sdev->same_target_siblings);
262 INIT_LIST_HEAD(&sdev->cmd_list);
263 INIT_LIST_HEAD(&sdev->starved_entry);
264 INIT_LIST_HEAD(&sdev->event_list);
265 spin_lock_init(&sdev->list_lock);
266 INIT_WORK(&sdev->event_work, scsi_evt_thread);
268 sdev->sdev_gendev.parent = get_device(&starget->dev);
269 sdev->sdev_target = starget;
271 /* usually NULL and set by ->slave_alloc instead */
272 sdev->hostdata = hostdata;
274 /* if the device needs this changing, it may do so in the
275 * slave_configure function */
276 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
279 * Some low level driver could use device->type
281 sdev->type = -1;
284 * Assume that the device will have handshaking problems,
285 * and then fix this field later if it turns out it
286 * doesn't
288 sdev->borken = 1;
290 sdev->request_queue = scsi_alloc_queue(sdev);
291 if (!sdev->request_queue) {
292 /* release fn is set up in scsi_sysfs_device_initialise, so
293 * have to free and put manually here */
294 put_device(&starget->dev);
295 kfree(sdev);
296 goto out;
299 sdev->request_queue->queuedata = sdev;
300 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
302 scsi_sysfs_device_initialize(sdev);
304 if (shost->hostt->slave_alloc) {
305 ret = shost->hostt->slave_alloc(sdev);
306 if (ret) {
308 * if LLDD reports slave not present, don't clutter
309 * console with alloc failure messages
311 if (ret == -ENXIO)
312 display_failure_msg = 0;
313 goto out_device_destroy;
317 return sdev;
319 out_device_destroy:
320 scsi_device_set_state(sdev, SDEV_DEL);
321 transport_destroy_device(&sdev->sdev_gendev);
322 put_device(&sdev->sdev_dev);
323 put_device(&sdev->sdev_gendev);
324 out:
325 if (display_failure_msg)
326 printk(ALLOC_FAILURE_MSG, __func__);
327 return NULL;
330 static void scsi_target_destroy(struct scsi_target *starget)
332 struct device *dev = &starget->dev;
333 struct Scsi_Host *shost = dev_to_shost(dev->parent);
334 unsigned long flags;
336 transport_destroy_device(dev);
337 spin_lock_irqsave(shost->host_lock, flags);
338 if (shost->hostt->target_destroy)
339 shost->hostt->target_destroy(starget);
340 list_del_init(&starget->siblings);
341 spin_unlock_irqrestore(shost->host_lock, flags);
342 put_device(dev);
345 static void scsi_target_dev_release(struct device *dev)
347 struct device *parent = dev->parent;
348 struct scsi_target *starget = to_scsi_target(dev);
350 kfree(starget);
351 put_device(parent);
354 static struct device_type scsi_target_type = {
355 .name = "scsi_target",
356 .release = scsi_target_dev_release,
359 int scsi_is_target_device(const struct device *dev)
361 return dev->type == &scsi_target_type;
363 EXPORT_SYMBOL(scsi_is_target_device);
365 static struct scsi_target *__scsi_find_target(struct device *parent,
366 int channel, uint id)
368 struct scsi_target *starget, *found_starget = NULL;
369 struct Scsi_Host *shost = dev_to_shost(parent);
371 * Search for an existing target for this sdev.
373 list_for_each_entry(starget, &shost->__targets, siblings) {
374 if (starget->id == id &&
375 starget->channel == channel) {
376 found_starget = starget;
377 break;
380 if (found_starget)
381 get_device(&found_starget->dev);
383 return found_starget;
387 * scsi_alloc_target - allocate a new or find an existing target
388 * @parent: parent of the target (need not be a scsi host)
389 * @channel: target channel number (zero if no channels)
390 * @id: target id number
392 * Return an existing target if one exists, provided it hasn't already
393 * gone into STARGET_DEL state, otherwise allocate a new target.
395 * The target is returned with an incremented reference, so the caller
396 * is responsible for both reaping and doing a last put
398 static struct scsi_target *scsi_alloc_target(struct device *parent,
399 int channel, uint id)
401 struct Scsi_Host *shost = dev_to_shost(parent);
402 struct device *dev = NULL;
403 unsigned long flags;
404 const int size = sizeof(struct scsi_target)
405 + shost->transportt->target_size;
406 struct scsi_target *starget;
407 struct scsi_target *found_target;
408 int error;
410 starget = kzalloc(size, GFP_KERNEL);
411 if (!starget) {
412 printk(KERN_ERR "%s: allocation failure\n", __func__);
413 return NULL;
415 dev = &starget->dev;
416 device_initialize(dev);
417 starget->reap_ref = 1;
418 dev->parent = get_device(parent);
419 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
420 #ifndef CONFIG_SYSFS_DEPRECATED
421 dev->bus = &scsi_bus_type;
422 #endif
423 dev->type = &scsi_target_type;
424 starget->id = id;
425 starget->channel = channel;
426 starget->can_queue = 0;
427 INIT_LIST_HEAD(&starget->siblings);
428 INIT_LIST_HEAD(&starget->devices);
429 starget->state = STARGET_CREATED;
430 starget->scsi_level = SCSI_2;
431 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
432 retry:
433 spin_lock_irqsave(shost->host_lock, flags);
435 found_target = __scsi_find_target(parent, channel, id);
436 if (found_target)
437 goto found;
439 list_add_tail(&starget->siblings, &shost->__targets);
440 spin_unlock_irqrestore(shost->host_lock, flags);
441 /* allocate and add */
442 transport_setup_device(dev);
443 if (shost->hostt->target_alloc) {
444 error = shost->hostt->target_alloc(starget);
446 if(error) {
447 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
448 /* don't want scsi_target_reap to do the final
449 * put because it will be under the host lock */
450 scsi_target_destroy(starget);
451 return NULL;
454 get_device(dev);
456 return starget;
458 found:
459 found_target->reap_ref++;
460 spin_unlock_irqrestore(shost->host_lock, flags);
461 if (found_target->state != STARGET_DEL) {
462 put_device(parent);
463 kfree(starget);
464 return found_target;
466 /* Unfortunately, we found a dying target; need to
467 * wait until it's dead before we can get a new one */
468 put_device(&found_target->dev);
469 flush_scheduled_work();
470 goto retry;
473 static void scsi_target_reap_usercontext(struct work_struct *work)
475 struct scsi_target *starget =
476 container_of(work, struct scsi_target, ew.work);
478 transport_remove_device(&starget->dev);
479 device_del(&starget->dev);
480 scsi_target_destroy(starget);
484 * scsi_target_reap - check to see if target is in use and destroy if not
485 * @starget: target to be checked
487 * This is used after removing a LUN or doing a last put of the target
488 * it checks atomically that nothing is using the target and removes
489 * it if so.
491 void scsi_target_reap(struct scsi_target *starget)
493 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
494 unsigned long flags;
495 enum scsi_target_state state;
496 int empty;
498 spin_lock_irqsave(shost->host_lock, flags);
499 state = starget->state;
500 empty = --starget->reap_ref == 0 &&
501 list_empty(&starget->devices) ? 1 : 0;
502 spin_unlock_irqrestore(shost->host_lock, flags);
504 if (!empty)
505 return;
507 BUG_ON(state == STARGET_DEL);
508 starget->state = STARGET_DEL;
509 if (state == STARGET_CREATED)
510 scsi_target_destroy(starget);
511 else
512 execute_in_process_context(scsi_target_reap_usercontext,
513 &starget->ew);
517 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string
518 * @s: INQUIRY result string to sanitize
519 * @len: length of the string
521 * Description:
522 * The SCSI spec says that INQUIRY vendor, product, and revision
523 * strings must consist entirely of graphic ASCII characters,
524 * padded on the right with spaces. Since not all devices obey
525 * this rule, we will replace non-graphic or non-ASCII characters
526 * with spaces. Exception: a NUL character is interpreted as a
527 * string terminator, so all the following characters are set to
528 * spaces.
530 static void sanitize_inquiry_string(unsigned char *s, int len)
532 int terminated = 0;
534 for (; len > 0; (--len, ++s)) {
535 if (*s == 0)
536 terminated = 1;
537 if (terminated || *s < 0x20 || *s > 0x7e)
538 *s = ' ';
543 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
544 * @sdev: scsi_device to probe
545 * @inq_result: area to store the INQUIRY result
546 * @result_len: len of inq_result
547 * @bflags: store any bflags found here
549 * Description:
550 * Probe the lun associated with @req using a standard SCSI INQUIRY;
552 * If the INQUIRY is successful, zero is returned and the
553 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
554 * are copied to the scsi_device any flags value is stored in *@bflags.
556 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
557 int result_len, int *bflags)
559 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
560 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
561 int response_len = 0;
562 int pass, count, result;
563 struct scsi_sense_hdr sshdr;
565 *bflags = 0;
567 /* Perform up to 3 passes. The first pass uses a conservative
568 * transfer length of 36 unless sdev->inquiry_len specifies a
569 * different value. */
570 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
571 try_inquiry_len = first_inquiry_len;
572 pass = 1;
574 next_pass:
575 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
576 "scsi scan: INQUIRY pass %d length %d\n",
577 pass, try_inquiry_len));
579 /* Each pass gets up to three chances to ignore Unit Attention */
580 for (count = 0; count < 3; ++count) {
581 int resid;
583 memset(scsi_cmd, 0, 6);
584 scsi_cmd[0] = INQUIRY;
585 scsi_cmd[4] = (unsigned char) try_inquiry_len;
587 memset(inq_result, 0, try_inquiry_len);
589 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
590 inq_result, try_inquiry_len, &sshdr,
591 HZ / 2 + HZ * scsi_inq_timeout, 3,
592 &resid);
594 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s "
595 "with code 0x%x\n",
596 result ? "failed" : "successful", result));
598 if (result) {
600 * not-ready to ready transition [asc/ascq=0x28/0x0]
601 * or power-on, reset [asc/ascq=0x29/0x0], continue.
602 * INQUIRY should not yield UNIT_ATTENTION
603 * but many buggy devices do so anyway.
605 if ((driver_byte(result) & DRIVER_SENSE) &&
606 scsi_sense_valid(&sshdr)) {
607 if ((sshdr.sense_key == UNIT_ATTENTION) &&
608 ((sshdr.asc == 0x28) ||
609 (sshdr.asc == 0x29)) &&
610 (sshdr.ascq == 0))
611 continue;
613 } else {
615 * if nothing was transferred, we try
616 * again. It's a workaround for some USB
617 * devices.
619 if (resid == try_inquiry_len)
620 continue;
622 break;
625 if (result == 0) {
626 sanitize_inquiry_string(&inq_result[8], 8);
627 sanitize_inquiry_string(&inq_result[16], 16);
628 sanitize_inquiry_string(&inq_result[32], 4);
630 response_len = inq_result[4] + 5;
631 if (response_len > 255)
632 response_len = first_inquiry_len; /* sanity */
635 * Get any flags for this device.
637 * XXX add a bflags to scsi_device, and replace the
638 * corresponding bit fields in scsi_device, so bflags
639 * need not be passed as an argument.
641 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
642 &inq_result[16]);
644 /* When the first pass succeeds we gain information about
645 * what larger transfer lengths might work. */
646 if (pass == 1) {
647 if (BLIST_INQUIRY_36 & *bflags)
648 next_inquiry_len = 36;
649 else if (BLIST_INQUIRY_58 & *bflags)
650 next_inquiry_len = 58;
651 else if (sdev->inquiry_len)
652 next_inquiry_len = sdev->inquiry_len;
653 else
654 next_inquiry_len = response_len;
656 /* If more data is available perform the second pass */
657 if (next_inquiry_len > try_inquiry_len) {
658 try_inquiry_len = next_inquiry_len;
659 pass = 2;
660 goto next_pass;
664 } else if (pass == 2) {
665 printk(KERN_INFO "scsi scan: %d byte inquiry failed. "
666 "Consider BLIST_INQUIRY_36 for this device\n",
667 try_inquiry_len);
669 /* If this pass failed, the third pass goes back and transfers
670 * the same amount as we successfully got in the first pass. */
671 try_inquiry_len = first_inquiry_len;
672 pass = 3;
673 goto next_pass;
676 /* If the last transfer attempt got an error, assume the
677 * peripheral doesn't exist or is dead. */
678 if (result)
679 return -EIO;
681 /* Don't report any more data than the device says is valid */
682 sdev->inquiry_len = min(try_inquiry_len, response_len);
685 * XXX Abort if the response length is less than 36? If less than
686 * 32, the lookup of the device flags (above) could be invalid,
687 * and it would be possible to take an incorrect action - we do
688 * not want to hang because of a short INQUIRY. On the flip side,
689 * if the device is spun down or becoming ready (and so it gives a
690 * short INQUIRY), an abort here prevents any further use of the
691 * device, including spin up.
693 * On the whole, the best approach seems to be to assume the first
694 * 36 bytes are valid no matter what the device says. That's
695 * better than copying < 36 bytes to the inquiry-result buffer
696 * and displaying garbage for the Vendor, Product, or Revision
697 * strings.
699 if (sdev->inquiry_len < 36) {
700 printk(KERN_INFO "scsi scan: INQUIRY result too short (%d),"
701 " using 36\n", sdev->inquiry_len);
702 sdev->inquiry_len = 36;
706 * Related to the above issue:
708 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
709 * and if not ready, sent a START_STOP to start (maybe spin up) and
710 * then send the INQUIRY again, since the INQUIRY can change after
711 * a device is initialized.
713 * Ideally, start a device if explicitly asked to do so. This
714 * assumes that a device is spun up on power on, spun down on
715 * request, and then spun up on request.
719 * The scanning code needs to know the scsi_level, even if no
720 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
721 * non-zero LUNs can be scanned.
723 sdev->scsi_level = inq_result[2] & 0x07;
724 if (sdev->scsi_level >= 2 ||
725 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
726 sdev->scsi_level++;
727 sdev->sdev_target->scsi_level = sdev->scsi_level;
729 return 0;
733 * scsi_add_lun - allocate and fully initialze a scsi_device
734 * @sdev: holds information to be stored in the new scsi_device
735 * @inq_result: holds the result of a previous INQUIRY to the LUN
736 * @bflags: black/white list flag
737 * @async: 1 if this device is being scanned asynchronously
739 * Description:
740 * Initialize the scsi_device @sdev. Optionally set fields based
741 * on values in *@bflags.
743 * Return:
744 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
745 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
747 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
748 int *bflags, int async)
750 int ret;
753 * XXX do not save the inquiry, since it can change underneath us,
754 * save just vendor/model/rev.
756 * Rather than save it and have an ioctl that retrieves the saved
757 * value, have an ioctl that executes the same INQUIRY code used
758 * in scsi_probe_lun, let user level programs doing INQUIRY
759 * scanning run at their own risk, or supply a user level program
760 * that can correctly scan.
764 * Copy at least 36 bytes of INQUIRY data, so that we don't
765 * dereference unallocated memory when accessing the Vendor,
766 * Product, and Revision strings. Badly behaved devices may set
767 * the INQUIRY Additional Length byte to a small value, indicating
768 * these strings are invalid, but often they contain plausible data
769 * nonetheless. It doesn't matter if the device sent < 36 bytes
770 * total, since scsi_probe_lun() initializes inq_result with 0s.
772 sdev->inquiry = kmemdup(inq_result,
773 max_t(size_t, sdev->inquiry_len, 36),
774 GFP_ATOMIC);
775 if (sdev->inquiry == NULL)
776 return SCSI_SCAN_NO_RESPONSE;
778 sdev->vendor = (char *) (sdev->inquiry + 8);
779 sdev->model = (char *) (sdev->inquiry + 16);
780 sdev->rev = (char *) (sdev->inquiry + 32);
782 if (*bflags & BLIST_ISROM) {
783 sdev->type = TYPE_ROM;
784 sdev->removable = 1;
785 } else {
786 sdev->type = (inq_result[0] & 0x1f);
787 sdev->removable = (inq_result[1] & 0x80) >> 7;
790 switch (sdev->type) {
791 case TYPE_RBC:
792 case TYPE_TAPE:
793 case TYPE_DISK:
794 case TYPE_PRINTER:
795 case TYPE_MOD:
796 case TYPE_PROCESSOR:
797 case TYPE_SCANNER:
798 case TYPE_MEDIUM_CHANGER:
799 case TYPE_ENCLOSURE:
800 case TYPE_COMM:
801 case TYPE_RAID:
802 case TYPE_OSD:
803 sdev->writeable = 1;
804 break;
805 case TYPE_ROM:
806 case TYPE_WORM:
807 sdev->writeable = 0;
808 break;
809 default:
810 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
813 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
814 /* RBC and MMC devices can return SCSI-3 compliance and yet
815 * still not support REPORT LUNS, so make them act as
816 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
817 * specifically set */
818 if ((*bflags & BLIST_REPORTLUN2) == 0)
819 *bflags |= BLIST_NOREPORTLUN;
823 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
824 * spec says: The device server is capable of supporting the
825 * specified peripheral device type on this logical unit. However,
826 * the physical device is not currently connected to this logical
827 * unit.
829 * The above is vague, as it implies that we could treat 001 and
830 * 011 the same. Stay compatible with previous code, and create a
831 * scsi_device for a PQ of 1
833 * Don't set the device offline here; rather let the upper
834 * level drivers eval the PQ to decide whether they should
835 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
838 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
839 sdev->lockable = sdev->removable;
840 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
842 if (sdev->scsi_level >= SCSI_3 ||
843 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
844 sdev->ppr = 1;
845 if (inq_result[7] & 0x60)
846 sdev->wdtr = 1;
847 if (inq_result[7] & 0x10)
848 sdev->sdtr = 1;
850 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
851 "ANSI: %d%s\n", scsi_device_type(sdev->type),
852 sdev->vendor, sdev->model, sdev->rev,
853 sdev->inq_periph_qual, inq_result[2] & 0x07,
854 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
856 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
857 !(*bflags & BLIST_NOTQ))
858 sdev->tagged_supported = 1;
861 * Some devices (Texel CD ROM drives) have handshaking problems
862 * when used with the Seagate controllers. borken is initialized
863 * to 1, and then set it to 0 here.
865 if ((*bflags & BLIST_BORKEN) == 0)
866 sdev->borken = 0;
868 if (*bflags & BLIST_NO_ULD_ATTACH)
869 sdev->no_uld_attach = 1;
872 * Apparently some really broken devices (contrary to the SCSI
873 * standards) need to be selected without asserting ATN
875 if (*bflags & BLIST_SELECT_NO_ATN)
876 sdev->select_no_atn = 1;
879 * Maximum 512 sector transfer length
880 * broken RA4x00 Compaq Disk Array
882 if (*bflags & BLIST_MAX_512)
883 blk_queue_max_hw_sectors(sdev->request_queue, 512);
886 * Some devices may not want to have a start command automatically
887 * issued when a device is added.
889 if (*bflags & BLIST_NOSTARTONADD)
890 sdev->no_start_on_add = 1;
892 if (*bflags & BLIST_SINGLELUN)
893 scsi_target(sdev)->single_lun = 1;
895 sdev->use_10_for_rw = 1;
897 if (*bflags & BLIST_MS_SKIP_PAGE_08)
898 sdev->skip_ms_page_8 = 1;
900 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
901 sdev->skip_ms_page_3f = 1;
903 if (*bflags & BLIST_USE_10_BYTE_MS)
904 sdev->use_10_for_ms = 1;
906 /* set the device running here so that slave configure
907 * may do I/O */
908 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
909 if (ret) {
910 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
912 if (ret) {
913 sdev_printk(KERN_ERR, sdev,
914 "in wrong state %s to complete scan\n",
915 scsi_device_state_name(sdev->sdev_state));
916 return SCSI_SCAN_NO_RESPONSE;
920 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
921 sdev->use_192_bytes_for_3f = 1;
923 if (*bflags & BLIST_NOT_LOCKABLE)
924 sdev->lockable = 0;
926 if (*bflags & BLIST_RETRY_HWERROR)
927 sdev->retry_hwerror = 1;
929 transport_configure_device(&sdev->sdev_gendev);
931 if (sdev->host->hostt->slave_configure) {
932 ret = sdev->host->hostt->slave_configure(sdev);
933 if (ret) {
935 * if LLDD reports slave not present, don't clutter
936 * console with alloc failure messages
938 if (ret != -ENXIO) {
939 sdev_printk(KERN_ERR, sdev,
940 "failed to configure device\n");
942 return SCSI_SCAN_NO_RESPONSE;
946 sdev->max_queue_depth = sdev->queue_depth;
949 * Ok, the device is now all set up, we can
950 * register it and tell the rest of the kernel
951 * about it.
953 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
954 return SCSI_SCAN_NO_RESPONSE;
956 return SCSI_SCAN_LUN_PRESENT;
959 #ifdef CONFIG_SCSI_LOGGING
960 /**
961 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
962 * @buf: Output buffer with at least end-first+1 bytes of space
963 * @inq: Inquiry buffer (input)
964 * @first: Offset of string into inq
965 * @end: Index after last character in inq
967 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
968 unsigned first, unsigned end)
970 unsigned term = 0, idx;
972 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
973 if (inq[idx+first] > ' ') {
974 buf[idx] = inq[idx+first];
975 term = idx+1;
976 } else {
977 buf[idx] = ' ';
980 buf[term] = 0;
981 return buf;
983 #endif
986 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
987 * @starget: pointer to target device structure
988 * @lun: LUN of target device
989 * @bflagsp: store bflags here if not NULL
990 * @sdevp: probe the LUN corresponding to this scsi_device
991 * @rescan: if nonzero skip some code only needed on first scan
992 * @hostdata: passed to scsi_alloc_sdev()
994 * Description:
995 * Call scsi_probe_lun, if a LUN with an attached device is found,
996 * allocate and set it up by calling scsi_add_lun.
998 * Return:
999 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1000 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1001 * attached at the LUN
1002 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1004 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1005 uint lun, int *bflagsp,
1006 struct scsi_device **sdevp, int rescan,
1007 void *hostdata)
1009 struct scsi_device *sdev;
1010 unsigned char *result;
1011 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1012 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1015 * The rescan flag is used as an optimization, the first scan of a
1016 * host adapter calls into here with rescan == 0.
1018 sdev = scsi_device_lookup_by_target(starget, lun);
1019 if (sdev) {
1020 if (rescan || !scsi_device_created(sdev)) {
1021 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1022 "scsi scan: device exists on %s\n",
1023 dev_name(&sdev->sdev_gendev)));
1024 if (sdevp)
1025 *sdevp = sdev;
1026 else
1027 scsi_device_put(sdev);
1029 if (bflagsp)
1030 *bflagsp = scsi_get_device_flags(sdev,
1031 sdev->vendor,
1032 sdev->model);
1033 return SCSI_SCAN_LUN_PRESENT;
1035 scsi_device_put(sdev);
1036 } else
1037 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1038 if (!sdev)
1039 goto out;
1041 result = kmalloc(result_len, GFP_ATOMIC |
1042 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
1043 if (!result)
1044 goto out_free_sdev;
1046 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1047 goto out_free_result;
1049 if (bflagsp)
1050 *bflagsp = bflags;
1052 * result contains valid SCSI INQUIRY data.
1054 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
1056 * For a Peripheral qualifier 3 (011b), the SCSI
1057 * spec says: The device server is not capable of
1058 * supporting a physical device on this logical
1059 * unit.
1061 * For disks, this implies that there is no
1062 * logical disk configured at sdev->lun, but there
1063 * is a target id responding.
1065 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1066 " peripheral qualifier of 3, device not"
1067 " added\n"))
1068 if (lun == 0) {
1069 SCSI_LOG_SCAN_BUS(1, {
1070 unsigned char vend[9];
1071 unsigned char mod[17];
1073 sdev_printk(KERN_INFO, sdev,
1074 "scsi scan: consider passing scsi_mod."
1075 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1076 scsi_inq_str(vend, result, 8, 16),
1077 scsi_inq_str(mod, result, 16, 32));
1082 res = SCSI_SCAN_TARGET_PRESENT;
1083 goto out_free_result;
1087 * Some targets may set slight variations of PQ and PDT to signal
1088 * that no LUN is present, so don't add sdev in these cases.
1089 * Two specific examples are:
1090 * 1) NetApp targets: return PQ=1, PDT=0x1f
1091 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1092 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1094 * References:
1095 * 1) SCSI SPC-3, pp. 145-146
1096 * PQ=1: "A peripheral device having the specified peripheral
1097 * device type is not connected to this logical unit. However, the
1098 * device server is capable of supporting the specified peripheral
1099 * device type on this logical unit."
1100 * PDT=0x1f: "Unknown or no device type"
1101 * 2) USB UFI 1.0, p. 20
1102 * PDT=00h Direct-access device (floppy)
1103 * PDT=1Fh none (no FDD connected to the requested logical unit)
1105 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1106 (result[0] & 0x1f) == 0x1f &&
1107 !scsi_is_wlun(lun)) {
1108 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1109 "scsi scan: peripheral device type"
1110 " of 31, no device added\n"));
1111 res = SCSI_SCAN_TARGET_PRESENT;
1112 goto out_free_result;
1115 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1116 if (res == SCSI_SCAN_LUN_PRESENT) {
1117 if (bflags & BLIST_KEY) {
1118 sdev->lockable = 0;
1119 scsi_unlock_floptical(sdev, result);
1123 out_free_result:
1124 kfree(result);
1125 out_free_sdev:
1126 if (res == SCSI_SCAN_LUN_PRESENT) {
1127 if (sdevp) {
1128 if (scsi_device_get(sdev) == 0) {
1129 *sdevp = sdev;
1130 } else {
1131 __scsi_remove_device(sdev);
1132 res = SCSI_SCAN_NO_RESPONSE;
1135 } else
1136 __scsi_remove_device(sdev);
1137 out:
1138 return res;
1142 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1143 * @starget: pointer to target structure to scan
1144 * @bflags: black/white list flag for LUN 0
1145 * @scsi_level: Which version of the standard does this device adhere to
1146 * @rescan: passed to scsi_probe_add_lun()
1148 * Description:
1149 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1150 * scanned) to some maximum lun until a LUN is found with no device
1151 * attached. Use the bflags to figure out any oddities.
1153 * Modifies sdevscan->lun.
1155 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1156 int bflags, int scsi_level, int rescan)
1158 unsigned int sparse_lun, lun, max_dev_lun;
1159 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1161 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
1162 "%s\n", dev_name(&starget->dev)));
1164 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1166 * If this device is known to support sparse multiple units,
1167 * override the other settings, and scan all of them. Normally,
1168 * SCSI-3 devices should be scanned via the REPORT LUNS.
1170 if (bflags & BLIST_SPARSELUN) {
1171 max_dev_lun = shost->max_lun;
1172 sparse_lun = 1;
1173 } else
1174 sparse_lun = 0;
1177 * If less than SCSI_1_CSS, and no special lun scaning, stop
1178 * scanning; this matches 2.4 behaviour, but could just be a bug
1179 * (to continue scanning a SCSI_1_CSS device).
1181 * This test is broken. We might not have any device on lun0 for
1182 * a sparselun device, and if that's the case then how would we
1183 * know the real scsi_level, eh? It might make sense to just not
1184 * scan any SCSI_1 device for non-0 luns, but that check would best
1185 * go into scsi_alloc_sdev() and just have it return null when asked
1186 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1188 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1189 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1190 == 0))
1191 return;
1194 * If this device is known to support multiple units, override
1195 * the other settings, and scan all of them.
1197 if (bflags & BLIST_FORCELUN)
1198 max_dev_lun = shost->max_lun;
1200 * REGAL CDC-4X: avoid hang after LUN 4
1202 if (bflags & BLIST_MAX5LUN)
1203 max_dev_lun = min(5U, max_dev_lun);
1205 * Do not scan SCSI-2 or lower device past LUN 7, unless
1206 * BLIST_LARGELUN.
1208 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1209 max_dev_lun = min(8U, max_dev_lun);
1212 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1213 * until we reach the max, or no LUN is found and we are not
1214 * sparse_lun.
1216 for (lun = 1; lun < max_dev_lun; ++lun)
1217 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1218 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1219 !sparse_lun)
1220 return;
1224 * scsilun_to_int: convert a scsi_lun to an int
1225 * @scsilun: struct scsi_lun to be converted.
1227 * Description:
1228 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
1229 * integer, and return the result. The caller must check for
1230 * truncation before using this function.
1232 * Notes:
1233 * The struct scsi_lun is assumed to be four levels, with each level
1234 * effectively containing a SCSI byte-ordered (big endian) short; the
1235 * addressing bits of each level are ignored (the highest two bits).
1236 * For a description of the LUN format, post SCSI-3 see the SCSI
1237 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
1239 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
1240 * the integer: 0x0b030a04
1242 int scsilun_to_int(struct scsi_lun *scsilun)
1244 int i;
1245 unsigned int lun;
1247 lun = 0;
1248 for (i = 0; i < sizeof(lun); i += 2)
1249 lun = lun | (((scsilun->scsi_lun[i] << 8) |
1250 scsilun->scsi_lun[i + 1]) << (i * 8));
1251 return lun;
1253 EXPORT_SYMBOL(scsilun_to_int);
1256 * int_to_scsilun: reverts an int into a scsi_lun
1257 * @lun: integer to be reverted
1258 * @scsilun: struct scsi_lun to be set.
1260 * Description:
1261 * Reverts the functionality of the scsilun_to_int, which packed
1262 * an 8-byte lun value into an int. This routine unpacks the int
1263 * back into the lun value.
1264 * Note: the scsilun_to_int() routine does not truly handle all
1265 * 8bytes of the lun value. This functions restores only as much
1266 * as was set by the routine.
1268 * Notes:
1269 * Given an integer : 0x0b030a04, this function returns a
1270 * scsi_lun of : struct scsi_lun of: 0a 04 0b 03 00 00 00 00
1273 void int_to_scsilun(unsigned int lun, struct scsi_lun *scsilun)
1275 int i;
1277 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
1279 for (i = 0; i < sizeof(lun); i += 2) {
1280 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
1281 scsilun->scsi_lun[i+1] = lun & 0xFF;
1282 lun = lun >> 16;
1285 EXPORT_SYMBOL(int_to_scsilun);
1288 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1289 * @starget: which target
1290 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1291 * @rescan: nonzero if we can skip code only needed on first scan
1293 * Description:
1294 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1295 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1297 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1298 * LUNs even if it's older than SCSI-3.
1299 * If BLIST_NOREPORTLUN is set, return 1 always.
1300 * If BLIST_NOLUN is set, return 0 always.
1302 * Return:
1303 * 0: scan completed (or no memory, so further scanning is futile)
1304 * 1: could not scan with REPORT LUN
1306 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1307 int rescan)
1309 char devname[64];
1310 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1311 unsigned int length;
1312 unsigned int lun;
1313 unsigned int num_luns;
1314 unsigned int retries;
1315 int result;
1316 struct scsi_lun *lunp, *lun_data;
1317 u8 *data;
1318 struct scsi_sense_hdr sshdr;
1319 struct scsi_device *sdev;
1320 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1321 int ret = 0;
1324 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1325 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1326 * support more than 8 LUNs.
1328 if (bflags & BLIST_NOREPORTLUN)
1329 return 1;
1330 if (starget->scsi_level < SCSI_2 &&
1331 starget->scsi_level != SCSI_UNKNOWN)
1332 return 1;
1333 if (starget->scsi_level < SCSI_3 &&
1334 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1335 return 1;
1336 if (bflags & BLIST_NOLUN)
1337 return 0;
1339 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1340 sdev = scsi_alloc_sdev(starget, 0, NULL);
1341 if (!sdev)
1342 return 0;
1343 if (scsi_device_get(sdev)) {
1344 __scsi_remove_device(sdev);
1345 return 0;
1349 sprintf(devname, "host %d channel %d id %d",
1350 shost->host_no, sdev->channel, sdev->id);
1353 * Allocate enough to hold the header (the same size as one scsi_lun)
1354 * plus the max number of luns we are requesting.
1356 * Reallocating and trying again (with the exact amount we need)
1357 * would be nice, but then we need to somehow limit the size
1358 * allocated based on the available memory and the limits of
1359 * kmalloc - we don't want a kmalloc() failure of a huge value to
1360 * prevent us from finding any LUNs on this target.
1362 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
1363 lun_data = kmalloc(length, GFP_ATOMIC |
1364 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1365 if (!lun_data) {
1366 printk(ALLOC_FAILURE_MSG, __func__);
1367 goto out;
1370 scsi_cmd[0] = REPORT_LUNS;
1373 * bytes 1 - 5: reserved, set to zero.
1375 memset(&scsi_cmd[1], 0, 5);
1378 * bytes 6 - 9: length of the command.
1380 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
1381 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
1382 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
1383 scsi_cmd[9] = (unsigned char) length & 0xff;
1385 scsi_cmd[10] = 0; /* reserved */
1386 scsi_cmd[11] = 0; /* control */
1389 * We can get a UNIT ATTENTION, for example a power on/reset, so
1390 * retry a few times (like sd.c does for TEST UNIT READY).
1391 * Experience shows some combinations of adapter/devices get at
1392 * least two power on/resets.
1394 * Illegal requests (for devices that do not support REPORT LUNS)
1395 * should come through as a check condition, and will not generate
1396 * a retry.
1398 for (retries = 0; retries < 3; retries++) {
1399 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
1400 " REPORT LUNS to %s (try %d)\n", devname,
1401 retries));
1403 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1404 lun_data, length, &sshdr,
1405 SCSI_TIMEOUT + 4 * HZ, 3, NULL);
1407 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
1408 " %s (try %d) result 0x%x\n", result
1409 ? "failed" : "successful", retries, result));
1410 if (result == 0)
1411 break;
1412 else if (scsi_sense_valid(&sshdr)) {
1413 if (sshdr.sense_key != UNIT_ATTENTION)
1414 break;
1418 if (result) {
1420 * The device probably does not support a REPORT LUN command
1422 ret = 1;
1423 goto out_err;
1427 * Get the length from the first four bytes of lun_data.
1429 data = (u8 *) lun_data->scsi_lun;
1430 length = ((data[0] << 24) | (data[1] << 16) |
1431 (data[2] << 8) | (data[3] << 0));
1433 num_luns = (length / sizeof(struct scsi_lun));
1434 if (num_luns > max_scsi_report_luns) {
1435 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1436 " of %d luns reported, try increasing"
1437 " max_scsi_report_luns.\n", devname,
1438 max_scsi_report_luns, num_luns);
1439 num_luns = max_scsi_report_luns;
1442 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1443 "scsi scan: REPORT LUN scan\n"));
1446 * Scan the luns in lun_data. The entry at offset 0 is really
1447 * the header, so start at 1 and go up to and including num_luns.
1449 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1450 lun = scsilun_to_int(lunp);
1453 * Check if the unused part of lunp is non-zero, and so
1454 * does not fit in lun.
1456 if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) {
1457 int i;
1460 * Output an error displaying the LUN in byte order,
1461 * this differs from what linux would print for the
1462 * integer LUN value.
1464 printk(KERN_WARNING "scsi: %s lun 0x", devname);
1465 data = (char *)lunp->scsi_lun;
1466 for (i = 0; i < sizeof(struct scsi_lun); i++)
1467 printk("%02x", data[i]);
1468 printk(" has a LUN larger than currently supported.\n");
1469 } else if (lun > sdev->host->max_lun) {
1470 printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
1471 " than allowed by the host adapter\n",
1472 devname, lun);
1473 } else {
1474 int res;
1476 res = scsi_probe_and_add_lun(starget,
1477 lun, NULL, NULL, rescan, NULL);
1478 if (res == SCSI_SCAN_NO_RESPONSE) {
1480 * Got some results, but now none, abort.
1482 sdev_printk(KERN_ERR, sdev,
1483 "Unexpected response"
1484 " from lun %d while scanning, scan"
1485 " aborted\n", lun);
1486 break;
1491 out_err:
1492 kfree(lun_data);
1493 out:
1494 scsi_device_put(sdev);
1495 if (scsi_device_created(sdev))
1497 * the sdev we used didn't appear in the report luns scan
1499 __scsi_remove_device(sdev);
1500 return ret;
1503 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1504 uint id, uint lun, void *hostdata)
1506 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1507 struct device *parent = &shost->shost_gendev;
1508 struct scsi_target *starget;
1510 if (strncmp(scsi_scan_type, "none", 4) == 0)
1511 return ERR_PTR(-ENODEV);
1513 starget = scsi_alloc_target(parent, channel, id);
1514 if (!starget)
1515 return ERR_PTR(-ENOMEM);
1517 mutex_lock(&shost->scan_mutex);
1518 if (!shost->async_scan)
1519 scsi_complete_async_scans();
1521 if (scsi_host_scan_allowed(shost))
1522 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1523 mutex_unlock(&shost->scan_mutex);
1524 scsi_target_reap(starget);
1525 put_device(&starget->dev);
1527 return sdev;
1529 EXPORT_SYMBOL(__scsi_add_device);
1531 int scsi_add_device(struct Scsi_Host *host, uint channel,
1532 uint target, uint lun)
1534 struct scsi_device *sdev =
1535 __scsi_add_device(host, channel, target, lun, NULL);
1536 if (IS_ERR(sdev))
1537 return PTR_ERR(sdev);
1539 scsi_device_put(sdev);
1540 return 0;
1542 EXPORT_SYMBOL(scsi_add_device);
1544 void scsi_rescan_device(struct device *dev)
1546 struct scsi_driver *drv;
1548 if (!dev->driver)
1549 return;
1551 drv = to_scsi_driver(dev->driver);
1552 if (try_module_get(drv->owner)) {
1553 if (drv->rescan)
1554 drv->rescan(dev);
1555 module_put(drv->owner);
1558 EXPORT_SYMBOL(scsi_rescan_device);
1560 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1561 unsigned int id, unsigned int lun, int rescan)
1563 struct Scsi_Host *shost = dev_to_shost(parent);
1564 int bflags = 0;
1565 int res;
1566 struct scsi_target *starget;
1568 if (shost->this_id == id)
1570 * Don't scan the host adapter
1572 return;
1574 starget = scsi_alloc_target(parent, channel, id);
1575 if (!starget)
1576 return;
1578 if (lun != SCAN_WILD_CARD) {
1580 * Scan for a specific host/chan/id/lun.
1582 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1583 goto out_reap;
1587 * Scan LUN 0, if there is some response, scan further. Ideally, we
1588 * would not configure LUN 0 until all LUNs are scanned.
1590 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1591 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1592 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1594 * The REPORT LUN did not scan the target,
1595 * do a sequential scan.
1597 scsi_sequential_lun_scan(starget, bflags,
1598 starget->scsi_level, rescan);
1601 out_reap:
1602 /* now determine if the target has any children at all
1603 * and if not, nuke it */
1604 scsi_target_reap(starget);
1606 put_device(&starget->dev);
1610 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1611 * @parent: host to scan
1612 * @channel: channel to scan
1613 * @id: target id to scan
1614 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1615 * @rescan: passed to LUN scanning routines
1617 * Description:
1618 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1619 * and possibly all LUNs on the target id.
1621 * First try a REPORT LUN scan, if that does not scan the target, do a
1622 * sequential scan of LUNs on the target id.
1624 void scsi_scan_target(struct device *parent, unsigned int channel,
1625 unsigned int id, unsigned int lun, int rescan)
1627 struct Scsi_Host *shost = dev_to_shost(parent);
1629 if (strncmp(scsi_scan_type, "none", 4) == 0)
1630 return;
1632 mutex_lock(&shost->scan_mutex);
1633 if (!shost->async_scan)
1634 scsi_complete_async_scans();
1636 if (scsi_host_scan_allowed(shost))
1637 __scsi_scan_target(parent, channel, id, lun, rescan);
1638 mutex_unlock(&shost->scan_mutex);
1640 EXPORT_SYMBOL(scsi_scan_target);
1642 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1643 unsigned int id, unsigned int lun, int rescan)
1645 uint order_id;
1647 if (id == SCAN_WILD_CARD)
1648 for (id = 0; id < shost->max_id; ++id) {
1650 * XXX adapter drivers when possible (FCP, iSCSI)
1651 * could modify max_id to match the current max,
1652 * not the absolute max.
1654 * XXX add a shost id iterator, so for example,
1655 * the FC ID can be the same as a target id
1656 * without a huge overhead of sparse id's.
1658 if (shost->reverse_ordering)
1660 * Scan from high to low id.
1662 order_id = shost->max_id - id - 1;
1663 else
1664 order_id = id;
1665 __scsi_scan_target(&shost->shost_gendev, channel,
1666 order_id, lun, rescan);
1668 else
1669 __scsi_scan_target(&shost->shost_gendev, channel,
1670 id, lun, rescan);
1673 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1674 unsigned int id, unsigned int lun, int rescan)
1676 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1677 "%s: <%u:%u:%u>\n",
1678 __func__, channel, id, lun));
1680 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1681 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1682 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1683 return -EINVAL;
1685 mutex_lock(&shost->scan_mutex);
1686 if (!shost->async_scan)
1687 scsi_complete_async_scans();
1689 if (scsi_host_scan_allowed(shost)) {
1690 if (channel == SCAN_WILD_CARD)
1691 for (channel = 0; channel <= shost->max_channel;
1692 channel++)
1693 scsi_scan_channel(shost, channel, id, lun,
1694 rescan);
1695 else
1696 scsi_scan_channel(shost, channel, id, lun, rescan);
1698 mutex_unlock(&shost->scan_mutex);
1700 return 0;
1703 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1705 struct scsi_device *sdev;
1706 shost_for_each_device(sdev, shost) {
1707 if (!scsi_host_scan_allowed(shost) ||
1708 scsi_sysfs_add_sdev(sdev) != 0)
1709 __scsi_remove_device(sdev);
1714 * scsi_prep_async_scan - prepare for an async scan
1715 * @shost: the host which will be scanned
1716 * Returns: a cookie to be passed to scsi_finish_async_scan()
1718 * Tells the midlayer this host is going to do an asynchronous scan.
1719 * It reserves the host's position in the scanning list and ensures
1720 * that other asynchronous scans started after this one won't affect the
1721 * ordering of the discovered devices.
1723 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1725 struct async_scan_data *data;
1726 unsigned long flags;
1728 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1729 return NULL;
1731 if (shost->async_scan) {
1732 printk("%s called twice for host %d", __func__,
1733 shost->host_no);
1734 dump_stack();
1735 return NULL;
1738 data = kmalloc(sizeof(*data), GFP_KERNEL);
1739 if (!data)
1740 goto err;
1741 data->shost = scsi_host_get(shost);
1742 if (!data->shost)
1743 goto err;
1744 init_completion(&data->prev_finished);
1746 mutex_lock(&shost->scan_mutex);
1747 spin_lock_irqsave(shost->host_lock, flags);
1748 shost->async_scan = 1;
1749 spin_unlock_irqrestore(shost->host_lock, flags);
1750 mutex_unlock(&shost->scan_mutex);
1752 spin_lock(&async_scan_lock);
1753 if (list_empty(&scanning_hosts))
1754 complete(&data->prev_finished);
1755 list_add_tail(&data->list, &scanning_hosts);
1756 spin_unlock(&async_scan_lock);
1758 return data;
1760 err:
1761 kfree(data);
1762 return NULL;
1766 * scsi_finish_async_scan - asynchronous scan has finished
1767 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1769 * All the devices currently attached to this host have been found.
1770 * This function announces all the devices it has found to the rest
1771 * of the system.
1773 static void scsi_finish_async_scan(struct async_scan_data *data)
1775 struct Scsi_Host *shost;
1776 unsigned long flags;
1778 if (!data)
1779 return;
1781 shost = data->shost;
1783 mutex_lock(&shost->scan_mutex);
1785 if (!shost->async_scan) {
1786 printk("%s called twice for host %d", __func__,
1787 shost->host_no);
1788 dump_stack();
1789 mutex_unlock(&shost->scan_mutex);
1790 return;
1793 wait_for_completion(&data->prev_finished);
1795 scsi_sysfs_add_devices(shost);
1797 spin_lock_irqsave(shost->host_lock, flags);
1798 shost->async_scan = 0;
1799 spin_unlock_irqrestore(shost->host_lock, flags);
1801 mutex_unlock(&shost->scan_mutex);
1803 spin_lock(&async_scan_lock);
1804 list_del(&data->list);
1805 if (!list_empty(&scanning_hosts)) {
1806 struct async_scan_data *next = list_entry(scanning_hosts.next,
1807 struct async_scan_data, list);
1808 complete(&next->prev_finished);
1810 spin_unlock(&async_scan_lock);
1812 scsi_host_put(shost);
1813 kfree(data);
1816 static void do_scsi_scan_host(struct Scsi_Host *shost)
1818 if (shost->hostt->scan_finished) {
1819 unsigned long start = jiffies;
1820 if (shost->hostt->scan_start)
1821 shost->hostt->scan_start(shost);
1823 while (!shost->hostt->scan_finished(shost, jiffies - start))
1824 msleep(10);
1825 } else {
1826 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1827 SCAN_WILD_CARD, 0);
1831 static int do_scan_async(void *_data)
1833 struct async_scan_data *data = _data;
1834 do_scsi_scan_host(data->shost);
1835 scsi_finish_async_scan(data);
1836 return 0;
1840 * scsi_scan_host - scan the given adapter
1841 * @shost: adapter to scan
1843 void scsi_scan_host(struct Scsi_Host *shost)
1845 struct task_struct *p;
1846 struct async_scan_data *data;
1848 if (strncmp(scsi_scan_type, "none", 4) == 0)
1849 return;
1851 data = scsi_prep_async_scan(shost);
1852 if (!data) {
1853 do_scsi_scan_host(shost);
1854 return;
1857 p = kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no);
1858 if (IS_ERR(p))
1859 do_scan_async(data);
1861 EXPORT_SYMBOL(scsi_scan_host);
1863 void scsi_forget_host(struct Scsi_Host *shost)
1865 struct scsi_device *sdev;
1866 unsigned long flags;
1868 restart:
1869 spin_lock_irqsave(shost->host_lock, flags);
1870 list_for_each_entry(sdev, &shost->__devices, siblings) {
1871 if (sdev->sdev_state == SDEV_DEL)
1872 continue;
1873 spin_unlock_irqrestore(shost->host_lock, flags);
1874 __scsi_remove_device(sdev);
1875 goto restart;
1877 spin_unlock_irqrestore(shost->host_lock, flags);
1881 * Function: scsi_get_host_dev()
1883 * Purpose: Create a scsi_device that points to the host adapter itself.
1885 * Arguments: SHpnt - Host that needs a scsi_device
1887 * Lock status: None assumed.
1889 * Returns: The scsi_device or NULL
1891 * Notes:
1892 * Attach a single scsi_device to the Scsi_Host - this should
1893 * be made to look like a "pseudo-device" that points to the
1894 * HA itself.
1896 * Note - this device is not accessible from any high-level
1897 * drivers (including generics), which is probably not
1898 * optimal. We can add hooks later to attach
1900 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1902 struct scsi_device *sdev = NULL;
1903 struct scsi_target *starget;
1905 mutex_lock(&shost->scan_mutex);
1906 if (!scsi_host_scan_allowed(shost))
1907 goto out;
1908 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1909 if (!starget)
1910 goto out;
1912 sdev = scsi_alloc_sdev(starget, 0, NULL);
1913 if (sdev)
1914 sdev->borken = 0;
1915 else
1916 scsi_target_reap(starget);
1917 put_device(&starget->dev);
1918 out:
1919 mutex_unlock(&shost->scan_mutex);
1920 return sdev;
1922 EXPORT_SYMBOL(scsi_get_host_dev);
1925 * Function: scsi_free_host_dev()
1927 * Purpose: Free a scsi_device that points to the host adapter itself.
1929 * Arguments: SHpnt - Host that needs a scsi_device
1931 * Lock status: None assumed.
1933 * Returns: Nothing
1935 * Notes:
1937 void scsi_free_host_dev(struct scsi_device *sdev)
1939 BUG_ON(sdev->id != sdev->host->this_id);
1941 __scsi_remove_device(sdev);
1943 EXPORT_SYMBOL(scsi_free_host_dev);