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_driver.h>
36 #include <scsi/scsi_devinfo.h>
37 #include <scsi/scsi_host.h>
38 #include <scsi/scsi_transport.h>
41 #include "scsi_priv.h"
42 #include "scsi_logging.h"
44 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
45 " SCSI scanning, some SCSI devices might not be configured\n"
48 * Prefix values for the SCSI id's (stored in driverfs name field)
50 #define SCSI_UID_SER_NUM 'S'
51 #define SCSI_UID_UNKNOWN 'Z'
54 * Return values of some of the scanning functions.
56 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
57 * includes allocation or general failures preventing IO from being sent.
59 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
62 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
65 #define SCSI_SCAN_NO_RESPONSE 0
66 #define SCSI_SCAN_TARGET_PRESENT 1
67 #define SCSI_SCAN_LUN_PRESENT 2
69 static char *scsi_null_device_strs = "nullnullnullnull";
71 #define MAX_SCSI_LUNS 512
73 #ifdef CONFIG_SCSI_MULTI_LUN
74 static unsigned int max_scsi_luns = MAX_SCSI_LUNS;
76 static unsigned int max_scsi_luns = 1;
79 module_param_named(max_luns, max_scsi_luns, int, S_IRUGO|S_IWUSR);
80 MODULE_PARM_DESC(max_luns,
81 "last scsi LUN (should be between 1 and 2^32-1)");
83 #ifdef CONFIG_SCSI_REPORT_LUNS
85 * max_scsi_report_luns: the maximum number of LUNS that will be
86 * returned from the REPORT LUNS command. 8 times this value must
87 * be allocated. In theory this could be up to an 8 byte value, but
88 * in practice, the maximum number of LUNs suppored by any device
91 static unsigned int max_scsi_report_luns = 128;
93 module_param_named(max_report_luns, max_scsi_report_luns, int, S_IRUGO|S_IWUSR);
94 MODULE_PARM_DESC(max_report_luns,
95 "REPORT LUNS maximum number of LUNS received (should be"
96 " between 1 and 16384)");
100 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
101 * @sreq: used to send the command
102 * @result: area to store the result of the MODE SENSE
105 * Send a vendor specific MODE SENSE (not a MODE SELECT) command using
106 * @sreq to unlock a device, storing the (unused) results into result.
107 * Called for BLIST_KEY devices.
109 static void scsi_unlock_floptical(struct scsi_request *sreq,
110 unsigned char *result)
112 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
114 printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
115 scsi_cmd[0] = MODE_SENSE;
119 scsi_cmd[4] = 0x2a; /* size */
121 sreq->sr_cmd_len = 0;
122 sreq->sr_data_direction = DMA_FROM_DEVICE;
123 scsi_wait_req(sreq, scsi_cmd, result, 0x2a /* size */, SCSI_TIMEOUT, 3);
127 * print_inquiry - printk the inquiry information
128 * @inq_result: printk this SCSI INQUIRY
131 * printk the vendor, model, and other information found in the
132 * INQUIRY data in @inq_result.
135 * Remove this, and replace with a hotplug event that logs any
136 * relevant information.
138 static void print_inquiry(unsigned char *inq_result)
142 printk(KERN_NOTICE " Vendor: ");
143 for (i = 8; i < 16; i++)
144 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
145 printk("%c", inq_result[i]);
150 for (i = 16; i < 32; i++)
151 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
152 printk("%c", inq_result[i]);
157 for (i = 32; i < 36; i++)
158 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
159 printk("%c", inq_result[i]);
165 i = inq_result[0] & 0x1f;
167 printk(KERN_NOTICE " Type: %s ",
169 MAX_SCSI_DEVICE_CODE ? scsi_device_types[i] :
171 printk(" ANSI SCSI revision: %02x",
172 inq_result[2] & 0x07);
173 if ((inq_result[2] & 0x07) == 1 && (inq_result[3] & 0x0f) == 1)
180 * scsi_alloc_sdev - allocate and setup a scsi_Device
183 * Allocate, initialize for io, and return a pointer to a scsi_Device.
184 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
185 * adds scsi_Device to the appropriate list.
188 * scsi_Device pointer, or NULL on failure.
190 static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
191 uint channel, uint id, uint lun)
193 struct scsi_device *sdev, *device;
196 sdev = kmalloc(sizeof(*sdev) + shost->transportt->size, GFP_ATOMIC);
200 memset(sdev, 0, sizeof(*sdev));
201 sdev->vendor = scsi_null_device_strs;
202 sdev->model = scsi_null_device_strs;
203 sdev->rev = scsi_null_device_strs;
207 sdev->channel = channel;
208 sdev->sdev_state = SDEV_CREATED;
209 INIT_LIST_HEAD(&sdev->siblings);
210 INIT_LIST_HEAD(&sdev->same_target_siblings);
211 INIT_LIST_HEAD(&sdev->cmd_list);
212 INIT_LIST_HEAD(&sdev->starved_entry);
213 spin_lock_init(&sdev->list_lock);
216 * Some low level driver could use device->type
221 * Assume that the device will have handshaking problems,
222 * and then fix this field later if it turns out it
227 spin_lock_init(&sdev->sdev_lock);
228 sdev->request_queue = scsi_alloc_queue(sdev);
229 if (!sdev->request_queue)
232 sdev->request_queue->queuedata = sdev;
233 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
235 if (shost->hostt->slave_alloc) {
236 if (shost->hostt->slave_alloc(sdev))
240 if (shost->transportt->setup) {
241 if (shost->transportt->setup(sdev))
242 goto out_cleanup_slave;
245 if (get_device(&sdev->host->shost_gendev)) {
247 device_initialize(&sdev->sdev_gendev);
248 sdev->sdev_gendev.parent = &sdev->host->shost_gendev;
249 sdev->sdev_gendev.bus = &scsi_bus_type;
250 sdev->sdev_gendev.release = scsi_device_dev_release;
251 sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
252 sdev->host->host_no, sdev->channel, sdev->id,
255 class_device_initialize(&sdev->sdev_classdev);
256 sdev->sdev_classdev.dev = &sdev->sdev_gendev;
257 sdev->sdev_classdev.class = &sdev_class;
258 snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
259 "%d:%d:%d:%d", sdev->host->host_no,
260 sdev->channel, sdev->id, sdev->lun);
262 class_device_initialize(&sdev->transport_classdev);
263 sdev->transport_classdev.dev = &sdev->sdev_gendev;
264 sdev->transport_classdev.class = sdev->host->transportt->class;
265 snprintf(sdev->transport_classdev.class_id, BUS_ID_SIZE,
266 "%d:%d:%d:%d", sdev->host->host_no,
267 sdev->channel, sdev->id, sdev->lun);
269 goto out_cleanup_transport;
272 * If there are any same target siblings, add this to the
275 spin_lock_irqsave(shost->host_lock, flags);
276 list_for_each_entry(device, &shost->__devices, siblings) {
277 if (device->id == sdev->id &&
278 device->channel == sdev->channel) {
279 list_add_tail(&sdev->same_target_siblings,
280 &device->same_target_siblings);
281 sdev->scsi_level = device->scsi_level;
287 * If there wasn't another lun already configured at this
288 * target, then default this device to SCSI_2 until we
291 if (!sdev->scsi_level)
292 sdev->scsi_level = SCSI_2;
294 list_add_tail(&sdev->siblings, &shost->__devices);
295 spin_unlock_irqrestore(shost->host_lock, flags);
298 out_cleanup_transport:
299 if (shost->transportt->cleanup)
300 shost->transportt->cleanup(sdev);
302 if (shost->hostt->slave_destroy)
303 shost->hostt->slave_destroy(sdev);
305 scsi_free_queue(sdev->request_queue);
309 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
314 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
315 * @sreq: used to send the INQUIRY
316 * @inq_result: area to store the INQUIRY result
317 * @bflags: store any bflags found here
320 * Probe the lun associated with @sreq using a standard SCSI INQUIRY;
322 * If the INQUIRY is successful, sreq->sr_result is zero and: the
323 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
324 * are copied to the Scsi_Device at @sreq->sr_device (sdev);
325 * any flags value is stored in *@bflags.
327 static void scsi_probe_lun(struct scsi_request *sreq, char *inq_result,
330 struct scsi_device *sdev = sreq->sr_device; /* a bit ugly */
331 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
332 int possible_inq_resp_len;
336 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY to host %d"
337 " channel %d id %d lun %d\n", sdev->host->host_no,
338 sdev->channel, sdev->id, sdev->lun));
340 memset(scsi_cmd, 0, 6);
341 scsi_cmd[0] = INQUIRY;
342 scsi_cmd[4] = 36; /* issue conservative alloc_length */
343 sreq->sr_cmd_len = 0;
344 sreq->sr_data_direction = DMA_FROM_DEVICE;
346 memset(inq_result, 0, 36);
347 scsi_wait_req(sreq, (void *) scsi_cmd, (void *) inq_result, 36,
348 SCSI_TIMEOUT + 4 * HZ, 3);
350 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: 1st INQUIRY %s with"
351 " code 0x%x\n", sreq->sr_result ?
352 "failed" : "successful", sreq->sr_result));
354 if (sreq->sr_result) {
355 if ((driver_byte(sreq->sr_result) & DRIVER_SENSE) != 0 &&
356 (sreq->sr_sense_buffer[2] & 0xf) == UNIT_ATTENTION &&
357 sreq->sr_sense_buffer[12] == 0x28 &&
358 sreq->sr_sense_buffer[13] == 0) {
359 /* not-ready to ready transition - good */
360 /* dpg: bogus? INQUIRY never returns UNIT_ATTENTION */
363 * assume no peripheral if any other sort of error
369 * Get any flags for this device.
371 * XXX add a bflags to Scsi_Device, and replace the corresponding
372 * bit fields in Scsi_Device, so bflags need not be passed as an
375 *bflags |= scsi_get_device_flags(sdev, &inq_result[8], &inq_result[16]);
377 possible_inq_resp_len = (unsigned char) inq_result[4] + 5;
378 if (BLIST_INQUIRY_36 & *bflags)
379 possible_inq_resp_len = 36;
380 else if (BLIST_INQUIRY_58 & *bflags)
381 possible_inq_resp_len = 58;
382 else if (possible_inq_resp_len > 255)
383 possible_inq_resp_len = 36; /* sanity */
385 if (possible_inq_resp_len > 36) { /* do additional INQUIRY */
386 memset(scsi_cmd, 0, 6);
387 scsi_cmd[0] = INQUIRY;
388 scsi_cmd[4] = (unsigned char) possible_inq_resp_len;
389 sreq->sr_cmd_len = 0;
390 sreq->sr_data_direction = DMA_FROM_DEVICE;
392 * re-zero inq_result just to be safe.
394 memset(inq_result, 0, possible_inq_resp_len);
395 scsi_wait_req(sreq, (void *) scsi_cmd,
397 possible_inq_resp_len, SCSI_TIMEOUT + 4 * HZ, 3);
398 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: 2nd INQUIRY"
399 " %s with code 0x%x\n", sreq->sr_result ?
400 "failed" : "successful", sreq->sr_result));
401 if (sreq->sr_result) {
402 /* if the longer inquiry has failed, flag the device
403 * as only accepting 36 byte inquiries and retry the
405 printk(KERN_INFO "scsi scan: %d byte inquiry failed"
406 " with code %d. Consider BLIST_INQUIRY_36 for"
407 " this device\n", possible_inq_resp_len,
409 *bflags = BLIST_INQUIRY_36;
414 * The INQUIRY can change, this means the length can change.
416 possible_inq_resp_len = (unsigned char) inq_result[4] + 5;
417 if (BLIST_INQUIRY_58 & *bflags)
418 possible_inq_resp_len = 58;
419 else if (possible_inq_resp_len > 255)
420 possible_inq_resp_len = 36; /* sanity */
423 sdev->inquiry_len = possible_inq_resp_len;
426 * XXX Abort if the response length is less than 36? If less than
427 * 32, the lookup of the device flags (above) could be invalid,
428 * and it would be possible to take an incorrect action - we do
429 * not want to hang because of a short INQUIRY. On the flip side,
430 * if the device is spun down or becoming ready (and so it gives a
431 * short INQUIRY), an abort here prevents any further use of the
432 * device, including spin up.
434 * Related to the above issue:
436 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
437 * and if not ready, sent a START_STOP to start (maybe spin up) and
438 * then send the INQUIRY again, since the INQUIRY can change after
439 * a device is initialized.
441 * Ideally, start a device if explicitly asked to do so. This
442 * assumes that a device is spun up on power on, spun down on
443 * request, and then spun up on request.
447 * The scanning code needs to know the scsi_level, even if no
448 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
449 * non-zero LUNs can be scanned.
451 sdev->scsi_level = inq_result[2] & 0x07;
452 if (sdev->scsi_level >= 2 ||
453 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
460 * scsi_add_lun - allocate and fully initialze a Scsi_Device
461 * @sdevscan: holds information to be stored in the new Scsi_Device
462 * @sdevnew: store the address of the newly allocated Scsi_Device
463 * @inq_result: holds the result of a previous INQUIRY to the LUN
464 * @bflags: black/white list flag
467 * Allocate and initialize a Scsi_Device matching sdevscan. Optionally
468 * set fields based on values in *@bflags. If @sdevnew is not
469 * NULL, store the address of the new Scsi_Device in *@sdevnew (needed
470 * when scanning a particular LUN).
473 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
474 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
476 static int scsi_add_lun(struct scsi_device *sdev, char *inq_result, int *bflags)
478 struct scsi_device *sdev_sibling;
479 struct scsi_target *starget;
483 * XXX do not save the inquiry, since it can change underneath us,
484 * save just vendor/model/rev.
486 * Rather than save it and have an ioctl that retrieves the saved
487 * value, have an ioctl that executes the same INQUIRY code used
488 * in scsi_probe_lun, let user level programs doing INQUIRY
489 * scanning run at their own risk, or supply a user level program
490 * that can correctly scan.
492 sdev->inquiry = kmalloc(sdev->inquiry_len, GFP_ATOMIC);
493 if (sdev->inquiry == NULL) {
494 return SCSI_SCAN_NO_RESPONSE;
497 memcpy(sdev->inquiry, inq_result, sdev->inquiry_len);
498 sdev->vendor = (char *) (sdev->inquiry + 8);
499 sdev->model = (char *) (sdev->inquiry + 16);
500 sdev->rev = (char *) (sdev->inquiry + 32);
502 if (*bflags & BLIST_ISROM) {
504 * It would be better to modify sdev->type, and set
505 * sdev->removable, but then the print_inquiry() output
506 * would not show TYPE_ROM; if print_inquiry() is removed
507 * the issue goes away.
509 inq_result[0] = TYPE_ROM;
510 inq_result[1] |= 0x80; /* removable */
513 switch (sdev->type = (inq_result[0] & 0x1f)) {
520 case TYPE_MEDIUM_CHANGER:
530 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
533 print_inquiry(inq_result);
536 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
537 * spec says: The device server is capable of supporting the
538 * specified peripheral device type on this logical unit. However,
539 * the physical device is not currently connected to this logical
542 * The above is vague, as it implies that we could treat 001 and
543 * 011 the same. Stay compatible with previous code, and create a
544 * Scsi_Device for a PQ of 1
546 * XXX Save the PQ field let the upper layers figure out if they
547 * want to attach or not to this device, do not set online FALSE;
548 * otherwise, offline devices still get an sd allocated, and they
551 if (((inq_result[0] >> 5) & 7) == 1) {
552 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: peripheral"
553 " qualifier of 1, device offlined\n"));
554 scsi_device_set_state(sdev, SDEV_OFFLINE);
557 sdev->removable = (0x80 & inq_result[1]) >> 7;
558 sdev->lockable = sdev->removable;
559 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
561 if (sdev->scsi_level >= SCSI_3 || (sdev->inquiry_len > 56 &&
562 inq_result[56] & 0x04))
564 if (inq_result[7] & 0x60)
566 if (inq_result[7] & 0x10)
569 sprintf(sdev->devfs_name, "scsi/host%d/bus%d/target%d/lun%d",
570 sdev->host->host_no, sdev->channel,
571 sdev->id, sdev->lun);
574 * End driverfs/devfs code.
577 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
578 !(*bflags & BLIST_NOTQ))
579 sdev->tagged_supported = 1;
581 * Some devices (Texel CD ROM drives) have handshaking problems
582 * when used with the Seagate controllers. borken is initialized
583 * to 1, and then set it to 0 here.
585 if ((*bflags & BLIST_BORKEN) == 0)
589 * Some devices may not want to have a start command automatically
590 * issued when a device is added.
592 if (*bflags & BLIST_NOSTARTONADD)
593 sdev->no_start_on_add = 1;
596 * If we need to allow I/O to only one of the luns attached to
597 * this target id at a time set single_lun, and allocate or modify
600 if (*bflags & BLIST_SINGLELUN) {
601 sdev->single_lun = 1;
602 spin_lock_irqsave(sdev->host->host_lock, flags);
605 * Search for an existing target for this sdev.
607 list_for_each_entry(sdev_sibling, &sdev->same_target_siblings,
608 same_target_siblings) {
609 if (sdev_sibling->sdev_target != NULL) {
610 starget = sdev_sibling->sdev_target;
615 starget = kmalloc(sizeof(*starget), GFP_ATOMIC);
617 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
618 spin_unlock_irqrestore(sdev->host->host_lock,
620 return SCSI_SCAN_NO_RESPONSE;
622 starget->starget_refcnt = 0;
623 starget->starget_sdev_user = NULL;
625 starget->starget_refcnt++;
626 sdev->sdev_target = starget;
627 spin_unlock_irqrestore(sdev->host->host_lock, flags);
630 /* if the device needs this changing, it may do so in the detect
632 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
634 sdev->use_10_for_rw = 1;
636 if (*bflags & BLIST_MS_SKIP_PAGE_08)
637 sdev->skip_ms_page_8 = 1;
639 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
640 sdev->skip_ms_page_3f = 1;
642 if (*bflags & BLIST_USE_10_BYTE_MS)
643 sdev->use_10_for_ms = 1;
645 /* set the device running here so that slave configure
647 scsi_device_set_state(sdev, SDEV_RUNNING);
649 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
650 sdev->use_192_bytes_for_3f = 1;
652 if(sdev->host->hostt->slave_configure)
653 sdev->host->hostt->slave_configure(sdev);
656 * Ok, the device is now all set up, we can
657 * register it and tell the rest of the kernel
660 scsi_sysfs_add_sdev(sdev);
662 return SCSI_SCAN_LUN_PRESENT;
666 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
667 * @sdevscan: probe the LUN corresponding to this Scsi_Device
668 * @sdevnew: store the value of any new Scsi_Device allocated
669 * @bflagsp: store bflags here if not NULL
672 * Call scsi_probe_lun, if a LUN with an attached device is found,
673 * allocate and set it up by calling scsi_add_lun.
676 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
677 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
678 * attached at the LUN
679 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
681 static int scsi_probe_and_add_lun(struct Scsi_Host *host,
682 uint channel, uint id, uint lun, int *bflagsp,
683 struct scsi_device **sdevp, int rescan)
685 struct scsi_device *sdev;
686 struct scsi_request *sreq;
687 unsigned char *result;
688 int bflags, res = SCSI_SCAN_NO_RESPONSE;
691 * The rescan flag is used as an optimization, the first scan of a
692 * host adapter calls into here with rescan == 0.
695 sdev = scsi_device_lookup(host, channel, id, lun);
697 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
698 "scsi scan: device exists on <%d:%d:%d:%d>\n",
699 host->host_no, channel, id, lun));
703 *bflagsp = scsi_get_device_flags(sdev,
706 /* XXX: bandaid until callers do refcounting */
707 scsi_device_put(sdev);
708 return SCSI_SCAN_LUN_PRESENT;
712 sdev = scsi_alloc_sdev(host, channel, id, lun);
715 sreq = scsi_allocate_request(sdev, GFP_ATOMIC);
718 result = kmalloc(256, GFP_ATOMIC |
719 (host->unchecked_isa_dma) ? __GFP_DMA : 0);
723 scsi_probe_lun(sreq, result, &bflags);
725 goto out_free_result;
728 * result contains valid SCSI INQUIRY data.
730 if ((result[0] >> 5) == 3) {
732 * For a Peripheral qualifier 3 (011b), the SCSI
733 * spec says: The device server is not capable of
734 * supporting a physical device on this logical
737 * For disks, this implies that there is no
738 * logical disk configured at sdev->lun, but there
739 * is a target id responding.
741 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
742 "scsi scan: peripheral qualifier of 3,"
743 " no device added\n"));
744 res = SCSI_SCAN_TARGET_PRESENT;
745 goto out_free_result;
748 res = scsi_add_lun(sdev, result, &bflags);
749 if (res == SCSI_SCAN_LUN_PRESENT) {
750 if (bflags & BLIST_KEY) {
752 scsi_unlock_floptical(sreq, result);
761 scsi_release_request(sreq);
763 if (res == SCSI_SCAN_LUN_PRESENT) {
767 if (sdev->host->hostt->slave_destroy)
768 sdev->host->hostt->slave_destroy(sdev);
769 if (sdev->host->transportt->cleanup)
770 sdev->host->transportt->cleanup(sdev);
771 put_device(&sdev->sdev_gendev);
778 * scsi_sequential_lun_scan - sequentially scan a SCSI target
779 * @sdevscan: scan the host, channel, and id of this Scsi_Device
780 * @bflags: black/white list flag for LUN 0
781 * @lun0_res: result of scanning LUN 0
784 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
785 * scanned) to some maximum lun until a LUN is found with no device
786 * attached. Use the bflags to figure out any oddities.
788 * Modifies sdevscan->lun.
790 static void scsi_sequential_lun_scan(struct Scsi_Host *shost, uint channel,
791 uint id, int bflags, int lun0_res, int scsi_level, int rescan)
793 unsigned int sparse_lun, lun, max_dev_lun;
795 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
796 " host %d channel %d id %d\n", shost->host_no,
799 max_dev_lun = min(max_scsi_luns, shost->max_lun);
801 * If this device is known to support sparse multiple units,
802 * override the other settings, and scan all of them. Normally,
803 * SCSI-3 devices should be scanned via the REPORT LUNS.
805 if (bflags & BLIST_SPARSELUN) {
806 max_dev_lun = shost->max_lun;
812 * If not sparse lun and no device attached at LUN 0 do not scan
815 if (!sparse_lun && (lun0_res != SCSI_SCAN_LUN_PRESENT))
819 * If less than SCSI_1_CSS, and no special lun scaning, stop
820 * scanning; this matches 2.4 behaviour, but could just be a bug
821 * (to continue scanning a SCSI_1_CSS device).
823 * This test is broken. We might not have any device on lun0 for
824 * a sparselun device, and if that's the case then how would we
825 * know the real scsi_level, eh? It might make sense to just not
826 * scan any SCSI_1 device for non-0 luns, but that check would best
827 * go into scsi_alloc_sdev() and just have it return null when asked
828 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
830 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
831 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
836 * If this device is known to support multiple units, override
837 * the other settings, and scan all of them.
839 if (bflags & BLIST_FORCELUN)
840 max_dev_lun = shost->max_lun;
842 * REGAL CDC-4X: avoid hang after LUN 4
844 if (bflags & BLIST_MAX5LUN)
845 max_dev_lun = min(5U, max_dev_lun);
847 * Do not scan SCSI-2 or lower device past LUN 7, unless
850 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
851 max_dev_lun = min(8U, max_dev_lun);
854 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
855 * until we reach the max, or no LUN is found and we are not
858 for (lun = 1; lun < max_dev_lun; ++lun)
859 if ((scsi_probe_and_add_lun(shost, channel, id, lun,
860 NULL, NULL, rescan) != SCSI_SCAN_LUN_PRESENT) &&
865 #ifdef CONFIG_SCSI_REPORT_LUNS
867 * scsilun_to_int: convert a scsi_lun to an int
868 * @scsilun: struct scsi_lun to be converted.
871 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
872 * integer, and return the result. The caller must check for
873 * truncation before using this function.
876 * The struct scsi_lun is assumed to be four levels, with each level
877 * effectively containing a SCSI byte-ordered (big endian) short; the
878 * addressing bits of each level are ignored (the highest two bits).
879 * For a description of the LUN format, post SCSI-3 see the SCSI
880 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
882 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
883 * the integer: 0x0b030a04
885 static int scsilun_to_int(struct scsi_lun *scsilun)
891 for (i = 0; i < sizeof(lun); i += 2)
892 lun = lun | (((scsilun->scsi_lun[i] << 8) |
893 scsilun->scsi_lun[i + 1]) << (i * 8));
898 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
899 * @sdevscan: scan the host, channel, and id of this Scsi_Device
902 * If @sdevscan is for a SCSI-3 or up device, send a REPORT LUN
903 * command, and scan the resulting list of LUNs by calling
904 * scsi_probe_and_add_lun.
906 * Modifies sdevscan->lun.
909 * 0: scan completed (or no memory, so further scanning is futile)
910 * 1: no report lun scan, or not configured
912 static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
916 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
919 unsigned int num_luns;
920 unsigned int retries;
921 struct scsi_lun *lunp, *lun_data;
922 struct scsi_request *sreq;
926 * Only support SCSI-3 and up devices.
928 if (sdev->scsi_level < SCSI_3)
930 if (bflags & BLIST_NOLUN)
933 sreq = scsi_allocate_request(sdev, GFP_ATOMIC);
937 sprintf(devname, "host %d channel %d id %d",
938 sdev->host->host_no, sdev->channel, sdev->id);
941 * Allocate enough to hold the header (the same size as one scsi_lun)
942 * plus the max number of luns we are requesting.
944 * Reallocating and trying again (with the exact amount we need)
945 * would be nice, but then we need to somehow limit the size
946 * allocated based on the available memory and the limits of
947 * kmalloc - we don't want a kmalloc() failure of a huge value to
948 * prevent us from finding any LUNs on this target.
950 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
951 lun_data = kmalloc(length, GFP_ATOMIC |
952 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
954 goto out_release_request;
956 scsi_cmd[0] = REPORT_LUNS;
959 * bytes 1 - 5: reserved, set to zero.
961 memset(&scsi_cmd[1], 0, 5);
964 * bytes 6 - 9: length of the command.
966 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
967 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
968 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
969 scsi_cmd[9] = (unsigned char) length & 0xff;
971 scsi_cmd[10] = 0; /* reserved */
972 scsi_cmd[11] = 0; /* control */
973 sreq->sr_cmd_len = 0;
974 sreq->sr_data_direction = DMA_FROM_DEVICE;
977 * We can get a UNIT ATTENTION, for example a power on/reset, so
978 * retry a few times (like sd.c does for TEST UNIT READY).
979 * Experience shows some combinations of adapter/devices get at
980 * least two power on/resets.
982 * Illegal requests (for devices that do not support REPORT LUNS)
983 * should come through as a check condition, and will not generate
986 for (retries = 0; retries < 3; retries++) {
987 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
988 " REPORT LUNS to %s (try %d)\n", devname,
990 scsi_wait_req(sreq, scsi_cmd, lun_data, length,
991 SCSI_TIMEOUT + 4*HZ, 3);
992 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
993 " %s (try %d) result 0x%x\n", sreq->sr_result
994 ? "failed" : "successful", retries,
996 if (sreq->sr_result == 0 ||
997 sreq->sr_sense_buffer[2] != UNIT_ATTENTION)
1001 if (sreq->sr_result) {
1003 * The device probably does not support a REPORT LUN command
1006 scsi_release_request(sreq);
1009 scsi_release_request(sreq);
1012 * Get the length from the first four bytes of lun_data.
1014 data = (u8 *) lun_data->scsi_lun;
1015 length = ((data[0] << 24) | (data[1] << 16) |
1016 (data[2] << 8) | (data[3] << 0));
1018 num_luns = (length / sizeof(struct scsi_lun));
1019 if (num_luns > max_scsi_report_luns) {
1020 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1021 " of %d luns reported, try increasing"
1022 " max_scsi_report_luns.\n", devname,
1023 max_scsi_report_luns, num_luns);
1024 num_luns = max_scsi_report_luns;
1027 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUN scan of"
1028 " host %d channel %d id %d\n", sdev->host->host_no,
1029 sdev->channel, sdev->id));
1032 * Scan the luns in lun_data. The entry at offset 0 is really
1033 * the header, so start at 1 and go up to and including num_luns.
1035 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1036 lun = scsilun_to_int(lunp);
1039 * Check if the unused part of lunp is non-zero, and so
1040 * does not fit in lun.
1042 if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) {
1046 * Output an error displaying the LUN in byte order,
1047 * this differs from what linux would print for the
1048 * integer LUN value.
1050 printk(KERN_WARNING "scsi: %s lun 0x", devname);
1051 data = (char *)lunp->scsi_lun;
1052 for (i = 0; i < sizeof(struct scsi_lun); i++)
1053 printk("%02x", data[i]);
1054 printk(" has a LUN larger than currently supported.\n");
1055 } else if (lun == 0) {
1057 * LUN 0 has already been scanned.
1059 } else if (lun > sdev->host->max_lun) {
1060 printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
1061 " than allowed by the host adapter\n",
1066 res = scsi_probe_and_add_lun(sdev->host, sdev->channel,
1067 sdev->id, lun, NULL, NULL, rescan);
1068 if (res == SCSI_SCAN_NO_RESPONSE) {
1070 * Got some results, but now none, abort.
1072 printk(KERN_ERR "scsi: Unexpected response"
1073 " from %s lun %d while scanning, scan"
1074 " aborted\n", devname, lun);
1083 out_release_request:
1084 scsi_release_request(sreq);
1087 * We are out of memory, don't try scanning any further.
1089 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
1093 # define scsi_report_lun_scan(sdev, blags, rescan) (1)
1094 #endif /* CONFIG_SCSI_REPORT_LUNS */
1096 struct scsi_device *scsi_add_device(struct Scsi_Host *shost,
1097 uint channel, uint id, uint lun)
1099 struct scsi_device *sdev;
1102 down(&shost->scan_mutex);
1103 res = scsi_probe_and_add_lun(shost, channel, id, lun, NULL, &sdev, 1);
1104 if (res != SCSI_SCAN_LUN_PRESENT)
1105 sdev = ERR_PTR(-ENODEV);
1106 up(&shost->scan_mutex);
1111 void scsi_rescan_device(struct device *dev)
1113 struct scsi_driver *drv;
1118 drv = to_scsi_driver(dev->driver);
1119 if (try_module_get(drv->owner)) {
1122 module_put(drv->owner);
1127 * scsi_scan_target - scan a target id, possibly including all LUNs on the
1129 * @sdevsca: Scsi_Device handle for scanning
1130 * @shost: host to scan
1131 * @channel: channel to scan
1132 * @id: target id to scan
1135 * Scan the target id on @shost, @channel, and @id. Scan at least LUN
1136 * 0, and possibly all LUNs on the target id.
1138 * Use the pre-allocated @sdevscan as a handle for the scanning. This
1139 * function sets sdevscan->host, sdevscan->id and sdevscan->lun; the
1140 * scanning functions modify sdevscan->lun.
1142 * First try a REPORT LUN scan, if that does not scan the target, do a
1143 * sequential scan of LUNs on the target id.
1145 static void scsi_scan_target(struct Scsi_Host *shost, unsigned int channel,
1146 unsigned int id, unsigned int lun, int rescan)
1150 struct scsi_device *sdev;
1152 if (shost->this_id == id)
1154 * Don't scan the host adapter
1158 if (lun != SCAN_WILD_CARD) {
1160 * Scan for a specific host/chan/id/lun.
1162 scsi_probe_and_add_lun(shost, channel, id, lun, NULL, NULL,
1168 * Scan LUN 0, if there is some response, scan further. Ideally, we
1169 * would not configure LUN 0 until all LUNs are scanned.
1171 res = scsi_probe_and_add_lun(shost, channel, id, 0, &bflags, &sdev,
1173 if (res == SCSI_SCAN_LUN_PRESENT) {
1174 if (scsi_report_lun_scan(sdev, bflags, rescan) != 0)
1176 * The REPORT LUN did not scan the target,
1177 * do a sequential scan.
1179 scsi_sequential_lun_scan(shost, channel, id, bflags,
1180 res, sdev->scsi_level, rescan);
1181 } else if (res == SCSI_SCAN_TARGET_PRESENT) {
1183 * There's a target here, but lun 0 is offline so we
1184 * can't use the report_lun scan. Fall back to a
1185 * sequential lun scan with a bflags of SPARSELUN and
1186 * a default scsi level of SCSI_2
1188 scsi_sequential_lun_scan(shost, channel, id, BLIST_SPARSELUN,
1189 SCSI_SCAN_TARGET_PRESENT, SCSI_2, rescan);
1193 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1194 unsigned int id, unsigned int lun, int rescan)
1198 if (id == SCAN_WILD_CARD)
1199 for (id = 0; id < shost->max_id; ++id) {
1201 * XXX adapter drivers when possible (FCP, iSCSI)
1202 * could modify max_id to match the current max,
1203 * not the absolute max.
1205 * XXX add a shost id iterator, so for example,
1206 * the FC ID can be the same as a target id
1207 * without a huge overhead of sparse id's.
1209 if (shost->reverse_ordering)
1211 * Scan from high to low id.
1213 order_id = shost->max_id - id - 1;
1216 scsi_scan_target(shost, channel, order_id, lun, rescan);
1219 scsi_scan_target(shost, channel, id, lun, rescan);
1222 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1223 unsigned int id, unsigned int lun, int rescan)
1225 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "%s: <%u:%u:%u:%u>\n",
1226 __FUNCTION__, shost->host_no, channel, id, lun));
1228 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1229 ((id != SCAN_WILD_CARD) && (id > shost->max_id)) ||
1230 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1233 down(&shost->scan_mutex);
1234 if (channel == SCAN_WILD_CARD)
1235 for (channel = 0; channel <= shost->max_channel; channel++)
1236 scsi_scan_channel(shost, channel, id, lun, rescan);
1238 scsi_scan_channel(shost, channel, id, lun, rescan);
1239 up(&shost->scan_mutex);
1245 * scsi_scan_host - scan the given adapter
1246 * @shost: adapter to scan
1248 void scsi_scan_host(struct Scsi_Host *shost)
1250 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1254 void scsi_forget_host(struct Scsi_Host *shost)
1256 struct scsi_device *sdev, *tmp;
1257 unsigned long flags;
1260 * Ok, this look a bit strange. We always look for the first device
1261 * on the list as scsi_remove_device removes them from it - thus we
1262 * also have to release the lock.
1263 * We don't need to get another reference to the device before
1264 * releasing the lock as we already own the reference from
1265 * scsi_register_device that's release in scsi_remove_device. And
1266 * after that we don't look at sdev anymore.
1268 spin_lock_irqsave(shost->host_lock, flags);
1269 list_for_each_entry_safe(sdev, tmp, &shost->__devices, siblings) {
1270 spin_unlock_irqrestore(shost->host_lock, flags);
1271 scsi_remove_device(sdev);
1272 spin_lock_irqsave(shost->host_lock, flags);
1274 spin_unlock_irqrestore(shost->host_lock, flags);
1278 * Function: scsi_get_host_dev()
1280 * Purpose: Create a Scsi_Device that points to the host adapter itself.
1282 * Arguments: SHpnt - Host that needs a Scsi_Device
1284 * Lock status: None assumed.
1286 * Returns: The Scsi_Device or NULL
1289 * Attach a single Scsi_Device to the Scsi_Host - this should
1290 * be made to look like a "pseudo-device" that points to the
1293 * Note - this device is not accessible from any high-level
1294 * drivers (including generics), which is probably not
1295 * optimal. We can add hooks later to attach
1297 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1299 struct scsi_device *sdev;
1301 sdev = scsi_alloc_sdev(shost, 0, shost->this_id, 0);
1309 * Function: scsi_free_host_dev()
1311 * Purpose: Free a scsi_device that points to the host adapter itself.
1313 * Arguments: SHpnt - Host that needs a Scsi_Device
1315 * Lock status: None assumed.
1321 void scsi_free_host_dev(struct scsi_device *sdev)
1323 BUG_ON(sdev->id != sdev->host->this_id);
1325 if (sdev->host->hostt->slave_destroy)
1326 sdev->host->hostt->slave_destroy(sdev);
1327 if (sdev->host->transportt->cleanup)
1328 sdev->host->transportt->cleanup(sdev);
1329 put_device(&sdev->sdev_gendev);