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/config.h>
29 #include <linux/module.h>
30 #include <linux/moduleparam.h>
31 #include <linux/init.h>
32 #include <linux/blkdev.h>
33 #include <asm/semaphore.h>
35 #include <scsi/scsi.h>
36 #include <scsi/scsi_device.h>
37 #include <scsi/scsi_driver.h>
38 #include <scsi/scsi_devinfo.h>
39 #include <scsi/scsi_host.h>
40 #include <scsi/scsi_request.h>
41 #include <scsi/scsi_transport.h>
43 #include "scsi_priv.h"
44 #include "scsi_logging.h"
46 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
47 " SCSI scanning, some SCSI devices might not be configured\n"
52 #define SCSI_TIMEOUT (2*HZ)
55 * Prefix values for the SCSI id's (stored in driverfs name field)
57 #define SCSI_UID_SER_NUM 'S'
58 #define SCSI_UID_UNKNOWN 'Z'
61 * Return values of some of the scanning functions.
63 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
64 * includes allocation or general failures preventing IO from being sent.
66 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
69 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
72 #define SCSI_SCAN_NO_RESPONSE 0
73 #define SCSI_SCAN_TARGET_PRESENT 1
74 #define SCSI_SCAN_LUN_PRESENT 2
76 static char *scsi_null_device_strs = "nullnullnullnull";
78 #define MAX_SCSI_LUNS 512
80 #ifdef CONFIG_SCSI_MULTI_LUN
81 static unsigned int max_scsi_luns = MAX_SCSI_LUNS;
83 static unsigned int max_scsi_luns = 1;
86 module_param_named(max_luns, max_scsi_luns, int, S_IRUGO|S_IWUSR);
87 MODULE_PARM_DESC(max_luns,
88 "last scsi LUN (should be between 1 and 2^32-1)");
91 * max_scsi_report_luns: the maximum number of LUNS that will be
92 * returned from the REPORT LUNS command. 8 times this value must
93 * be allocated. In theory this could be up to an 8 byte value, but
94 * in practice, the maximum number of LUNs suppored by any device
97 static unsigned int max_scsi_report_luns = 511;
99 module_param_named(max_report_luns, max_scsi_report_luns, int, S_IRUGO|S_IWUSR);
100 MODULE_PARM_DESC(max_report_luns,
101 "REPORT LUNS maximum number of LUNS received (should be"
102 " between 1 and 16384)");
104 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ+3;
106 module_param_named(inq_timeout, scsi_inq_timeout, int, S_IRUGO|S_IWUSR);
107 MODULE_PARM_DESC(inq_timeout,
108 "Timeout (in seconds) waiting for devices to answer INQUIRY."
109 " Default is 5. Some non-compliant devices need more.");
112 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
113 * @sreq: used to send the command
114 * @result: area to store the result of the MODE SENSE
117 * Send a vendor specific MODE SENSE (not a MODE SELECT) command using
118 * @sreq to unlock a device, storing the (unused) results into result.
119 * Called for BLIST_KEY devices.
121 static void scsi_unlock_floptical(struct scsi_request *sreq,
122 unsigned char *result)
124 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
126 printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
127 scsi_cmd[0] = MODE_SENSE;
131 scsi_cmd[4] = 0x2a; /* size */
133 sreq->sr_cmd_len = 0;
134 sreq->sr_data_direction = DMA_FROM_DEVICE;
135 scsi_wait_req(sreq, scsi_cmd, result, 0x2a /* size */, SCSI_TIMEOUT, 3);
139 * print_inquiry - printk the inquiry information
140 * @inq_result: printk this SCSI INQUIRY
143 * printk the vendor, model, and other information found in the
144 * INQUIRY data in @inq_result.
147 * Remove this, and replace with a hotplug event that logs any
148 * relevant information.
150 static void print_inquiry(unsigned char *inq_result)
154 printk(KERN_NOTICE " Vendor: ");
155 for (i = 8; i < 16; i++)
156 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
157 printk("%c", inq_result[i]);
162 for (i = 16; i < 32; i++)
163 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
164 printk("%c", inq_result[i]);
169 for (i = 32; i < 36; i++)
170 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
171 printk("%c", inq_result[i]);
177 i = inq_result[0] & 0x1f;
179 printk(KERN_NOTICE " Type: %s ",
181 MAX_SCSI_DEVICE_CODE ? scsi_device_types[i] :
183 printk(" ANSI SCSI revision: %02x",
184 inq_result[2] & 0x07);
185 if ((inq_result[2] & 0x07) == 1 && (inq_result[3] & 0x0f) == 1)
192 * scsi_alloc_sdev - allocate and setup a scsi_Device
195 * Allocate, initialize for io, and return a pointer to a scsi_Device.
196 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
197 * adds scsi_Device to the appropriate list.
200 * scsi_Device pointer, or NULL on failure.
202 static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
203 uint channel, uint id, uint lun)
205 struct scsi_device *sdev, *device;
208 sdev = kmalloc(sizeof(*sdev) + shost->transportt->size, GFP_ATOMIC);
212 memset(sdev, 0, sizeof(*sdev));
213 sdev->vendor = scsi_null_device_strs;
214 sdev->model = scsi_null_device_strs;
215 sdev->rev = scsi_null_device_strs;
219 sdev->channel = channel;
220 sdev->sdev_state = SDEV_CREATED;
221 INIT_LIST_HEAD(&sdev->siblings);
222 INIT_LIST_HEAD(&sdev->same_target_siblings);
223 INIT_LIST_HEAD(&sdev->cmd_list);
224 INIT_LIST_HEAD(&sdev->starved_entry);
225 spin_lock_init(&sdev->list_lock);
228 /* if the device needs this changing, it may do so in the
229 * slave_configure function */
230 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
233 * Some low level driver could use device->type
238 * Assume that the device will have handshaking problems,
239 * and then fix this field later if it turns out it
244 spin_lock_init(&sdev->sdev_lock);
245 sdev->request_queue = scsi_alloc_queue(sdev);
246 if (!sdev->request_queue)
249 sdev->request_queue->queuedata = sdev;
250 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
252 if (shost->hostt->slave_alloc) {
253 if (shost->hostt->slave_alloc(sdev))
257 if (shost->transportt->setup) {
258 if (shost->transportt->setup(sdev))
259 goto out_cleanup_slave;
262 if (get_device(&sdev->host->shost_gendev)) {
264 device_initialize(&sdev->sdev_gendev);
265 sdev->sdev_gendev.parent = &sdev->host->shost_gendev;
266 sdev->sdev_gendev.bus = &scsi_bus_type;
267 sdev->sdev_gendev.release = scsi_device_dev_release;
268 sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
269 sdev->host->host_no, sdev->channel, sdev->id,
272 class_device_initialize(&sdev->sdev_classdev);
273 sdev->sdev_classdev.dev = &sdev->sdev_gendev;
274 sdev->sdev_classdev.class = &sdev_class;
275 snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
276 "%d:%d:%d:%d", sdev->host->host_no,
277 sdev->channel, sdev->id, sdev->lun);
279 class_device_initialize(&sdev->transport_classdev);
280 sdev->transport_classdev.dev = &sdev->sdev_gendev;
281 sdev->transport_classdev.class = sdev->host->transportt->class;
282 snprintf(sdev->transport_classdev.class_id, BUS_ID_SIZE,
283 "%d:%d:%d:%d", sdev->host->host_no,
284 sdev->channel, sdev->id, sdev->lun);
286 goto out_cleanup_transport;
289 * If there are any same target siblings, add this to the
292 spin_lock_irqsave(shost->host_lock, flags);
293 list_for_each_entry(device, &shost->__devices, siblings) {
294 if (device->id == sdev->id &&
295 device->channel == sdev->channel) {
296 list_add_tail(&sdev->same_target_siblings,
297 &device->same_target_siblings);
298 sdev->scsi_level = device->scsi_level;
304 * If there wasn't another lun already configured at this
305 * target, then default this device to SCSI_2 until we
308 if (!sdev->scsi_level)
309 sdev->scsi_level = SCSI_2;
311 list_add_tail(&sdev->siblings, &shost->__devices);
312 spin_unlock_irqrestore(shost->host_lock, flags);
315 out_cleanup_transport:
316 if (shost->transportt->cleanup)
317 shost->transportt->cleanup(sdev);
319 if (shost->hostt->slave_destroy)
320 shost->hostt->slave_destroy(sdev);
322 scsi_free_queue(sdev->request_queue);
326 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
331 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
332 * @sreq: used to send the INQUIRY
333 * @inq_result: area to store the INQUIRY result
334 * @bflags: store any bflags found here
337 * Probe the lun associated with @sreq using a standard SCSI INQUIRY;
339 * If the INQUIRY is successful, sreq->sr_result is zero and: the
340 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
341 * are copied to the Scsi_Device at @sreq->sr_device (sdev);
342 * any flags value is stored in *@bflags.
344 static void scsi_probe_lun(struct scsi_request *sreq, char *inq_result,
347 struct scsi_device *sdev = sreq->sr_device; /* a bit ugly */
348 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
349 int possible_inq_resp_len;
354 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY to host %d"
355 " channel %d id %d lun %d\n", sdev->host->host_no,
356 sdev->channel, sdev->id, sdev->lun));
358 memset(scsi_cmd, 0, 6);
359 scsi_cmd[0] = INQUIRY;
360 scsi_cmd[4] = 36; /* issue conservative alloc_length */
361 sreq->sr_cmd_len = 0;
362 sreq->sr_data_direction = DMA_FROM_DEVICE;
364 memset(inq_result, 0, 36);
365 scsi_wait_req(sreq, (void *) scsi_cmd, (void *) inq_result, 36,
366 HZ/2 + HZ*scsi_inq_timeout, 3);
368 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: 1st INQUIRY %s with"
369 " code 0x%x\n", sreq->sr_result ?
370 "failed" : "successful", sreq->sr_result));
373 if (sreq->sr_result) {
374 if ((driver_byte(sreq->sr_result) & DRIVER_SENSE) != 0 &&
375 (sreq->sr_sense_buffer[2] & 0xf) == UNIT_ATTENTION &&
376 (sreq->sr_sense_buffer[12] == 0x28 ||
377 sreq->sr_sense_buffer[12] == 0x29) &&
378 sreq->sr_sense_buffer[13] == 0) {
379 /* not-ready to ready transition or power-on - good */
380 /* dpg: bogus? INQUIRY never returns UNIT_ATTENTION */
381 /* Supposedly, but many buggy devices do so anyway */
386 * assume no peripheral if any other sort of error
392 * Get any flags for this device.
394 * XXX add a bflags to Scsi_Device, and replace the corresponding
395 * bit fields in Scsi_Device, so bflags need not be passed as an
398 *bflags |= scsi_get_device_flags(sdev, &inq_result[8], &inq_result[16]);
400 possible_inq_resp_len = (unsigned char) inq_result[4] + 5;
401 if (BLIST_INQUIRY_36 & *bflags)
402 possible_inq_resp_len = 36;
403 else if (BLIST_INQUIRY_58 & *bflags)
404 possible_inq_resp_len = 58;
405 else if (possible_inq_resp_len > 255)
406 possible_inq_resp_len = 36; /* sanity */
408 if (possible_inq_resp_len > 36) { /* do additional INQUIRY */
409 memset(scsi_cmd, 0, 6);
410 scsi_cmd[0] = INQUIRY;
411 scsi_cmd[4] = (unsigned char) possible_inq_resp_len;
412 sreq->sr_cmd_len = 0;
413 sreq->sr_data_direction = DMA_FROM_DEVICE;
415 * re-zero inq_result just to be safe.
417 memset(inq_result, 0, possible_inq_resp_len);
418 scsi_wait_req(sreq, (void *) scsi_cmd,
420 possible_inq_resp_len, (1+scsi_inq_timeout)*(HZ/2), 3);
421 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: 2nd INQUIRY"
422 " %s with code 0x%x\n", sreq->sr_result ?
423 "failed" : "successful", sreq->sr_result));
424 if (sreq->sr_result) {
425 /* if the longer inquiry has failed, flag the device
426 * as only accepting 36 byte inquiries and retry the
428 printk(KERN_INFO "scsi scan: %d byte inquiry failed"
429 " with code %d. Consider BLIST_INQUIRY_36 for"
430 " this device\n", possible_inq_resp_len,
432 *bflags = BLIST_INQUIRY_36;
437 * The INQUIRY can change, this means the length can change.
439 possible_inq_resp_len = (unsigned char) inq_result[4] + 5;
440 if (BLIST_INQUIRY_58 & *bflags)
441 possible_inq_resp_len = 58;
442 else if (possible_inq_resp_len > 255)
443 possible_inq_resp_len = 36; /* sanity */
446 sdev->inquiry_len = possible_inq_resp_len;
449 * XXX Abort if the response length is less than 36? If less than
450 * 32, the lookup of the device flags (above) could be invalid,
451 * and it would be possible to take an incorrect action - we do
452 * not want to hang because of a short INQUIRY. On the flip side,
453 * if the device is spun down or becoming ready (and so it gives a
454 * short INQUIRY), an abort here prevents any further use of the
455 * device, including spin up.
457 * Related to the above issue:
459 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
460 * and if not ready, sent a START_STOP to start (maybe spin up) and
461 * then send the INQUIRY again, since the INQUIRY can change after
462 * a device is initialized.
464 * Ideally, start a device if explicitly asked to do so. This
465 * assumes that a device is spun up on power on, spun down on
466 * request, and then spun up on request.
470 * The scanning code needs to know the scsi_level, even if no
471 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
472 * non-zero LUNs can be scanned.
474 sdev->scsi_level = inq_result[2] & 0x07;
475 if (sdev->scsi_level >= 2 ||
476 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
483 * scsi_add_lun - allocate and fully initialze a Scsi_Device
484 * @sdevscan: holds information to be stored in the new Scsi_Device
485 * @sdevnew: store the address of the newly allocated Scsi_Device
486 * @inq_result: holds the result of a previous INQUIRY to the LUN
487 * @bflags: black/white list flag
490 * Allocate and initialize a Scsi_Device matching sdevscan. Optionally
491 * set fields based on values in *@bflags. If @sdevnew is not
492 * NULL, store the address of the new Scsi_Device in *@sdevnew (needed
493 * when scanning a particular LUN).
496 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
497 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
499 static int scsi_add_lun(struct scsi_device *sdev, char *inq_result, int *bflags)
501 struct scsi_device *sdev_sibling;
502 struct scsi_target *starget;
506 * XXX do not save the inquiry, since it can change underneath us,
507 * save just vendor/model/rev.
509 * Rather than save it and have an ioctl that retrieves the saved
510 * value, have an ioctl that executes the same INQUIRY code used
511 * in scsi_probe_lun, let user level programs doing INQUIRY
512 * scanning run at their own risk, or supply a user level program
513 * that can correctly scan.
515 sdev->inquiry = kmalloc(sdev->inquiry_len, GFP_ATOMIC);
516 if (sdev->inquiry == NULL) {
517 return SCSI_SCAN_NO_RESPONSE;
520 memcpy(sdev->inquiry, inq_result, sdev->inquiry_len);
521 sdev->vendor = (char *) (sdev->inquiry + 8);
522 sdev->model = (char *) (sdev->inquiry + 16);
523 sdev->rev = (char *) (sdev->inquiry + 32);
525 if (*bflags & BLIST_ISROM) {
527 * It would be better to modify sdev->type, and set
528 * sdev->removable, but then the print_inquiry() output
529 * would not show TYPE_ROM; if print_inquiry() is removed
530 * the issue goes away.
532 inq_result[0] = TYPE_ROM;
533 inq_result[1] |= 0x80; /* removable */
536 switch (sdev->type = (inq_result[0] & 0x1f)) {
543 case TYPE_MEDIUM_CHANGER:
553 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
556 print_inquiry(inq_result);
559 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
560 * spec says: The device server is capable of supporting the
561 * specified peripheral device type on this logical unit. However,
562 * the physical device is not currently connected to this logical
565 * The above is vague, as it implies that we could treat 001 and
566 * 011 the same. Stay compatible with previous code, and create a
567 * Scsi_Device for a PQ of 1
569 * Don't set the device offline here; rather let the upper
570 * level drivers eval the PQ to decide whether they should
571 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
574 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
575 sdev->removable = (0x80 & inq_result[1]) >> 7;
576 sdev->lockable = sdev->removable;
577 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
579 if (sdev->scsi_level >= SCSI_3 || (sdev->inquiry_len > 56 &&
580 inq_result[56] & 0x04))
582 if (inq_result[7] & 0x60)
584 if (inq_result[7] & 0x10)
587 sprintf(sdev->devfs_name, "scsi/host%d/bus%d/target%d/lun%d",
588 sdev->host->host_no, sdev->channel,
589 sdev->id, sdev->lun);
592 * End driverfs/devfs code.
595 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
596 !(*bflags & BLIST_NOTQ))
597 sdev->tagged_supported = 1;
599 * Some devices (Texel CD ROM drives) have handshaking problems
600 * when used with the Seagate controllers. borken is initialized
601 * to 1, and then set it to 0 here.
603 if ((*bflags & BLIST_BORKEN) == 0)
607 * Some devices may not want to have a start command automatically
608 * issued when a device is added.
610 if (*bflags & BLIST_NOSTARTONADD)
611 sdev->no_start_on_add = 1;
614 * If we need to allow I/O to only one of the luns attached to
615 * this target id at a time set single_lun, and allocate or modify
618 if (*bflags & BLIST_SINGLELUN) {
619 sdev->single_lun = 1;
620 spin_lock_irqsave(sdev->host->host_lock, flags);
623 * Search for an existing target for this sdev.
625 list_for_each_entry(sdev_sibling, &sdev->same_target_siblings,
626 same_target_siblings) {
627 if (sdev_sibling->sdev_target != NULL) {
628 starget = sdev_sibling->sdev_target;
633 starget = kmalloc(sizeof(*starget), GFP_ATOMIC);
635 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
636 spin_unlock_irqrestore(sdev->host->host_lock,
638 return SCSI_SCAN_NO_RESPONSE;
640 starget->starget_refcnt = 0;
641 starget->starget_sdev_user = NULL;
643 starget->starget_refcnt++;
644 sdev->sdev_target = starget;
645 spin_unlock_irqrestore(sdev->host->host_lock, flags);
648 sdev->use_10_for_rw = 1;
650 if (*bflags & BLIST_MS_SKIP_PAGE_08)
651 sdev->skip_ms_page_8 = 1;
653 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
654 sdev->skip_ms_page_3f = 1;
656 if (*bflags & BLIST_USE_10_BYTE_MS)
657 sdev->use_10_for_ms = 1;
659 /* set the device running here so that slave configure
661 scsi_device_set_state(sdev, SDEV_RUNNING);
663 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
664 sdev->use_192_bytes_for_3f = 1;
666 if (*bflags & BLIST_NOT_LOCKABLE)
669 if(sdev->host->hostt->slave_configure)
670 sdev->host->hostt->slave_configure(sdev);
673 * Ok, the device is now all set up, we can
674 * register it and tell the rest of the kernel
677 scsi_sysfs_add_sdev(sdev);
679 return SCSI_SCAN_LUN_PRESENT;
683 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
684 * @sdevscan: probe the LUN corresponding to this Scsi_Device
685 * @sdevnew: store the value of any new Scsi_Device allocated
686 * @bflagsp: store bflags here if not NULL
689 * Call scsi_probe_lun, if a LUN with an attached device is found,
690 * allocate and set it up by calling scsi_add_lun.
693 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
694 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
695 * attached at the LUN
696 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
698 static int scsi_probe_and_add_lun(struct Scsi_Host *host,
699 uint channel, uint id, uint lun, int *bflagsp,
700 struct scsi_device **sdevp, int rescan)
702 struct scsi_device *sdev;
703 struct scsi_request *sreq;
704 unsigned char *result;
705 int bflags, res = SCSI_SCAN_NO_RESPONSE;
708 * The rescan flag is used as an optimization, the first scan of a
709 * host adapter calls into here with rescan == 0.
712 sdev = scsi_device_lookup(host, channel, id, lun);
714 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
715 "scsi scan: device exists on <%d:%d:%d:%d>\n",
716 host->host_no, channel, id, lun));
720 *bflagsp = scsi_get_device_flags(sdev,
723 /* XXX: bandaid until callers do refcounting */
724 scsi_device_put(sdev);
725 return SCSI_SCAN_LUN_PRESENT;
729 sdev = scsi_alloc_sdev(host, channel, id, lun);
732 sreq = scsi_allocate_request(sdev, GFP_ATOMIC);
735 result = kmalloc(256, GFP_ATOMIC |
736 (host->unchecked_isa_dma) ? __GFP_DMA : 0);
740 scsi_probe_lun(sreq, result, &bflags);
742 goto out_free_result;
745 * result contains valid SCSI INQUIRY data.
747 if ((result[0] >> 5) == 3) {
749 * For a Peripheral qualifier 3 (011b), the SCSI
750 * spec says: The device server is not capable of
751 * supporting a physical device on this logical
754 * For disks, this implies that there is no
755 * logical disk configured at sdev->lun, but there
756 * is a target id responding.
758 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
759 "scsi scan: peripheral qualifier of 3,"
760 " no device added\n"));
761 res = SCSI_SCAN_TARGET_PRESENT;
762 goto out_free_result;
765 res = scsi_add_lun(sdev, result, &bflags);
766 if (res == SCSI_SCAN_LUN_PRESENT) {
767 if (bflags & BLIST_KEY) {
769 scsi_unlock_floptical(sreq, result);
778 scsi_release_request(sreq);
780 if (res == SCSI_SCAN_LUN_PRESENT) {
784 if (sdev->host->hostt->slave_destroy)
785 sdev->host->hostt->slave_destroy(sdev);
786 if (sdev->host->transportt->cleanup)
787 sdev->host->transportt->cleanup(sdev);
788 put_device(&sdev->sdev_gendev);
795 * scsi_sequential_lun_scan - sequentially scan a SCSI target
796 * @sdevscan: scan the host, channel, and id of this Scsi_Device
797 * @bflags: black/white list flag for LUN 0
798 * @lun0_res: result of scanning LUN 0
801 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
802 * scanned) to some maximum lun until a LUN is found with no device
803 * attached. Use the bflags to figure out any oddities.
805 * Modifies sdevscan->lun.
807 static void scsi_sequential_lun_scan(struct Scsi_Host *shost, uint channel,
808 uint id, int bflags, int lun0_res, int scsi_level, int rescan)
810 unsigned int sparse_lun, lun, max_dev_lun;
812 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
813 " host %d channel %d id %d\n", shost->host_no,
816 max_dev_lun = min(max_scsi_luns, shost->max_lun);
818 * If this device is known to support sparse multiple units,
819 * override the other settings, and scan all of them. Normally,
820 * SCSI-3 devices should be scanned via the REPORT LUNS.
822 if (bflags & BLIST_SPARSELUN) {
823 max_dev_lun = shost->max_lun;
829 * If not sparse lun and no device attached at LUN 0 do not scan
832 if (!sparse_lun && (lun0_res != SCSI_SCAN_LUN_PRESENT))
836 * If less than SCSI_1_CSS, and no special lun scaning, stop
837 * scanning; this matches 2.4 behaviour, but could just be a bug
838 * (to continue scanning a SCSI_1_CSS device).
840 * This test is broken. We might not have any device on lun0 for
841 * a sparselun device, and if that's the case then how would we
842 * know the real scsi_level, eh? It might make sense to just not
843 * scan any SCSI_1 device for non-0 luns, but that check would best
844 * go into scsi_alloc_sdev() and just have it return null when asked
845 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
847 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
848 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
853 * If this device is known to support multiple units, override
854 * the other settings, and scan all of them.
856 if (bflags & BLIST_FORCELUN)
857 max_dev_lun = shost->max_lun;
859 * REGAL CDC-4X: avoid hang after LUN 4
861 if (bflags & BLIST_MAX5LUN)
862 max_dev_lun = min(5U, max_dev_lun);
864 * Do not scan SCSI-2 or lower device past LUN 7, unless
867 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
868 max_dev_lun = min(8U, max_dev_lun);
871 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
872 * until we reach the max, or no LUN is found and we are not
875 for (lun = 1; lun < max_dev_lun; ++lun)
876 if ((scsi_probe_and_add_lun(shost, channel, id, lun,
877 NULL, NULL, rescan) != SCSI_SCAN_LUN_PRESENT) &&
883 * scsilun_to_int: convert a scsi_lun to an int
884 * @scsilun: struct scsi_lun to be converted.
887 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
888 * integer, and return the result. The caller must check for
889 * truncation before using this function.
892 * The struct scsi_lun is assumed to be four levels, with each level
893 * effectively containing a SCSI byte-ordered (big endian) short; the
894 * addressing bits of each level are ignored (the highest two bits).
895 * For a description of the LUN format, post SCSI-3 see the SCSI
896 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
898 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
899 * the integer: 0x0b030a04
901 static int scsilun_to_int(struct scsi_lun *scsilun)
907 for (i = 0; i < sizeof(lun); i += 2)
908 lun = lun | (((scsilun->scsi_lun[i] << 8) |
909 scsilun->scsi_lun[i + 1]) << (i * 8));
914 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
915 * @sdevscan: scan the host, channel, and id of this Scsi_Device
918 * If @sdevscan is for a SCSI-3 or up device, send a REPORT LUN
919 * command, and scan the resulting list of LUNs by calling
920 * scsi_probe_and_add_lun.
922 * Modifies sdevscan->lun.
925 * 0: scan completed (or no memory, so further scanning is futile)
926 * 1: no report lun scan, or not configured
928 static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
932 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
935 unsigned int num_luns;
936 unsigned int retries;
937 struct scsi_lun *lunp, *lun_data;
938 struct scsi_request *sreq;
942 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
943 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
944 * support more than 8 LUNs.
946 if ((bflags & BLIST_NOREPORTLUN) ||
947 sdev->scsi_level < SCSI_2 ||
948 (sdev->scsi_level < SCSI_3 &&
949 (!(bflags & BLIST_REPORTLUN2) || sdev->host->max_lun <= 8)) )
951 if (bflags & BLIST_NOLUN)
954 sreq = scsi_allocate_request(sdev, GFP_ATOMIC);
958 sprintf(devname, "host %d channel %d id %d",
959 sdev->host->host_no, sdev->channel, sdev->id);
962 * Allocate enough to hold the header (the same size as one scsi_lun)
963 * plus the max number of luns we are requesting.
965 * Reallocating and trying again (with the exact amount we need)
966 * would be nice, but then we need to somehow limit the size
967 * allocated based on the available memory and the limits of
968 * kmalloc - we don't want a kmalloc() failure of a huge value to
969 * prevent us from finding any LUNs on this target.
971 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
972 lun_data = kmalloc(length, GFP_ATOMIC |
973 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
975 goto out_release_request;
977 scsi_cmd[0] = REPORT_LUNS;
980 * bytes 1 - 5: reserved, set to zero.
982 memset(&scsi_cmd[1], 0, 5);
985 * bytes 6 - 9: length of the command.
987 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
988 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
989 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
990 scsi_cmd[9] = (unsigned char) length & 0xff;
992 scsi_cmd[10] = 0; /* reserved */
993 scsi_cmd[11] = 0; /* control */
994 sreq->sr_cmd_len = 0;
995 sreq->sr_data_direction = DMA_FROM_DEVICE;
998 * We can get a UNIT ATTENTION, for example a power on/reset, so
999 * retry a few times (like sd.c does for TEST UNIT READY).
1000 * Experience shows some combinations of adapter/devices get at
1001 * least two power on/resets.
1003 * Illegal requests (for devices that do not support REPORT LUNS)
1004 * should come through as a check condition, and will not generate
1007 for (retries = 0; retries < 3; retries++) {
1008 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
1009 " REPORT LUNS to %s (try %d)\n", devname,
1011 scsi_wait_req(sreq, scsi_cmd, lun_data, length,
1012 SCSI_TIMEOUT + 4*HZ, 3);
1013 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
1014 " %s (try %d) result 0x%x\n", sreq->sr_result
1015 ? "failed" : "successful", retries,
1017 if (sreq->sr_result == 0 ||
1018 sreq->sr_sense_buffer[2] != UNIT_ATTENTION)
1022 if (sreq->sr_result) {
1024 * The device probably does not support a REPORT LUN command
1027 scsi_release_request(sreq);
1030 scsi_release_request(sreq);
1033 * Get the length from the first four bytes of lun_data.
1035 data = (u8 *) lun_data->scsi_lun;
1036 length = ((data[0] << 24) | (data[1] << 16) |
1037 (data[2] << 8) | (data[3] << 0));
1039 num_luns = (length / sizeof(struct scsi_lun));
1040 if (num_luns > max_scsi_report_luns) {
1041 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1042 " of %d luns reported, try increasing"
1043 " max_scsi_report_luns.\n", devname,
1044 max_scsi_report_luns, num_luns);
1045 num_luns = max_scsi_report_luns;
1048 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUN scan of"
1049 " host %d channel %d id %d\n", sdev->host->host_no,
1050 sdev->channel, sdev->id));
1053 * Scan the luns in lun_data. The entry at offset 0 is really
1054 * the header, so start at 1 and go up to and including num_luns.
1056 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1057 lun = scsilun_to_int(lunp);
1060 * Check if the unused part of lunp is non-zero, and so
1061 * does not fit in lun.
1063 if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) {
1067 * Output an error displaying the LUN in byte order,
1068 * this differs from what linux would print for the
1069 * integer LUN value.
1071 printk(KERN_WARNING "scsi: %s lun 0x", devname);
1072 data = (char *)lunp->scsi_lun;
1073 for (i = 0; i < sizeof(struct scsi_lun); i++)
1074 printk("%02x", data[i]);
1075 printk(" has a LUN larger than currently supported.\n");
1076 } else if (lun == 0) {
1078 * LUN 0 has already been scanned.
1080 } else if (lun > sdev->host->max_lun) {
1081 printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
1082 " than allowed by the host adapter\n",
1087 res = scsi_probe_and_add_lun(sdev->host, sdev->channel,
1088 sdev->id, lun, NULL, NULL, rescan);
1089 if (res == SCSI_SCAN_NO_RESPONSE) {
1091 * Got some results, but now none, abort.
1093 printk(KERN_ERR "scsi: Unexpected response"
1094 " from %s lun %d while scanning, scan"
1095 " aborted\n", devname, lun);
1104 out_release_request:
1105 scsi_release_request(sreq);
1108 * We are out of memory, don't try scanning any further.
1110 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
1114 struct scsi_device *scsi_add_device(struct Scsi_Host *shost,
1115 uint channel, uint id, uint lun)
1117 struct scsi_device *sdev;
1120 down(&shost->scan_mutex);
1121 res = scsi_probe_and_add_lun(shost, channel, id, lun, NULL, &sdev, 1);
1122 if (res != SCSI_SCAN_LUN_PRESENT)
1123 sdev = ERR_PTR(-ENODEV);
1124 up(&shost->scan_mutex);
1129 void scsi_rescan_device(struct device *dev)
1131 struct scsi_driver *drv;
1136 drv = to_scsi_driver(dev->driver);
1137 if (try_module_get(drv->owner)) {
1140 module_put(drv->owner);
1145 * scsi_scan_target - scan a target id, possibly including all LUNs on the
1147 * @sdevsca: Scsi_Device handle for scanning
1148 * @shost: host to scan
1149 * @channel: channel to scan
1150 * @id: target id to scan
1153 * Scan the target id on @shost, @channel, and @id. Scan at least LUN
1154 * 0, and possibly all LUNs on the target id.
1156 * Use the pre-allocated @sdevscan as a handle for the scanning. This
1157 * function sets sdevscan->host, sdevscan->id and sdevscan->lun; the
1158 * scanning functions modify sdevscan->lun.
1160 * First try a REPORT LUN scan, if that does not scan the target, do a
1161 * sequential scan of LUNs on the target id.
1163 static void scsi_scan_target(struct Scsi_Host *shost, unsigned int channel,
1164 unsigned int id, unsigned int lun, int rescan)
1168 struct scsi_device *sdev;
1170 if (shost->this_id == id)
1172 * Don't scan the host adapter
1176 if (lun != SCAN_WILD_CARD) {
1178 * Scan for a specific host/chan/id/lun.
1180 scsi_probe_and_add_lun(shost, channel, id, lun, NULL, NULL,
1186 * Scan LUN 0, if there is some response, scan further. Ideally, we
1187 * would not configure LUN 0 until all LUNs are scanned.
1189 res = scsi_probe_and_add_lun(shost, channel, id, 0, &bflags, &sdev,
1191 if (res == SCSI_SCAN_LUN_PRESENT) {
1192 if (scsi_report_lun_scan(sdev, bflags, rescan) != 0)
1194 * The REPORT LUN did not scan the target,
1195 * do a sequential scan.
1197 scsi_sequential_lun_scan(shost, channel, id, bflags,
1198 res, sdev->scsi_level, rescan);
1199 } else if (res == SCSI_SCAN_TARGET_PRESENT) {
1201 * There's a target here, but lun 0 is offline so we
1202 * can't use the report_lun scan. Fall back to a
1203 * sequential lun scan with a bflags of SPARSELUN and
1204 * a default scsi level of SCSI_2
1206 scsi_sequential_lun_scan(shost, channel, id, BLIST_SPARSELUN,
1207 SCSI_SCAN_TARGET_PRESENT, SCSI_2, rescan);
1211 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1212 unsigned int id, unsigned int lun, int rescan)
1216 if (id == SCAN_WILD_CARD)
1217 for (id = 0; id < shost->max_id; ++id) {
1219 * XXX adapter drivers when possible (FCP, iSCSI)
1220 * could modify max_id to match the current max,
1221 * not the absolute max.
1223 * XXX add a shost id iterator, so for example,
1224 * the FC ID can be the same as a target id
1225 * without a huge overhead of sparse id's.
1227 if (shost->reverse_ordering)
1229 * Scan from high to low id.
1231 order_id = shost->max_id - id - 1;
1234 scsi_scan_target(shost, channel, order_id, lun, rescan);
1237 scsi_scan_target(shost, channel, id, lun, rescan);
1240 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1241 unsigned int id, unsigned int lun, int rescan)
1243 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "%s: <%u:%u:%u:%u>\n",
1244 __FUNCTION__, shost->host_no, channel, id, lun));
1246 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1247 ((id != SCAN_WILD_CARD) && (id > shost->max_id)) ||
1248 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1251 down(&shost->scan_mutex);
1252 if (channel == SCAN_WILD_CARD)
1253 for (channel = 0; channel <= shost->max_channel; channel++)
1254 scsi_scan_channel(shost, channel, id, lun, rescan);
1256 scsi_scan_channel(shost, channel, id, lun, rescan);
1257 up(&shost->scan_mutex);
1263 * scsi_scan_host - scan the given adapter
1264 * @shost: adapter to scan
1266 void scsi_scan_host(struct Scsi_Host *shost)
1268 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1272 void scsi_forget_host(struct Scsi_Host *shost)
1274 struct scsi_device *sdev, *tmp;
1275 unsigned long flags;
1278 * Ok, this look a bit strange. We always look for the first device
1279 * on the list as scsi_remove_device removes them from it - thus we
1280 * also have to release the lock.
1281 * We don't need to get another reference to the device before
1282 * releasing the lock as we already own the reference from
1283 * scsi_register_device that's release in scsi_remove_device. And
1284 * after that we don't look at sdev anymore.
1286 spin_lock_irqsave(shost->host_lock, flags);
1287 list_for_each_entry_safe(sdev, tmp, &shost->__devices, siblings) {
1288 spin_unlock_irqrestore(shost->host_lock, flags);
1289 scsi_remove_device(sdev);
1290 spin_lock_irqsave(shost->host_lock, flags);
1292 spin_unlock_irqrestore(shost->host_lock, flags);
1296 * Function: scsi_get_host_dev()
1298 * Purpose: Create a Scsi_Device that points to the host adapter itself.
1300 * Arguments: SHpnt - Host that needs a Scsi_Device
1302 * Lock status: None assumed.
1304 * Returns: The Scsi_Device or NULL
1307 * Attach a single Scsi_Device to the Scsi_Host - this should
1308 * be made to look like a "pseudo-device" that points to the
1311 * Note - this device is not accessible from any high-level
1312 * drivers (including generics), which is probably not
1313 * optimal. We can add hooks later to attach
1315 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1317 struct scsi_device *sdev;
1319 sdev = scsi_alloc_sdev(shost, 0, shost->this_id, 0);
1327 * Function: scsi_free_host_dev()
1329 * Purpose: Free a scsi_device that points to the host adapter itself.
1331 * Arguments: SHpnt - Host that needs a Scsi_Device
1333 * Lock status: None assumed.
1339 void scsi_free_host_dev(struct scsi_device *sdev)
1341 BUG_ON(sdev->id != sdev->host->this_id);
1343 if (sdev->host->hostt->slave_destroy)
1344 sdev->host->hostt->slave_destroy(sdev);
1345 if (sdev->host->transportt->cleanup)
1346 sdev->host->transportt->cleanup(sdev);
1347 put_device(&sdev->sdev_gendev);