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>
42 #include <scsi/scsi_eh.h>
44 #include "scsi_priv.h"
45 #include "scsi_logging.h"
47 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
48 " SCSI scanning, some SCSI devices might not be configured\n"
53 #define SCSI_TIMEOUT (2*HZ)
56 * Prefix values for the SCSI id's (stored in driverfs name field)
58 #define SCSI_UID_SER_NUM 'S'
59 #define SCSI_UID_UNKNOWN 'Z'
62 * Return values of some of the scanning functions.
64 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
65 * includes allocation or general failures preventing IO from being sent.
67 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
70 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
73 #define SCSI_SCAN_NO_RESPONSE 0
74 #define SCSI_SCAN_TARGET_PRESENT 1
75 #define SCSI_SCAN_LUN_PRESENT 2
77 static char *scsi_null_device_strs
= "nullnullnullnull";
79 #define MAX_SCSI_LUNS 512
81 #ifdef CONFIG_SCSI_MULTI_LUN
82 static unsigned int max_scsi_luns
= MAX_SCSI_LUNS
;
84 static unsigned int max_scsi_luns
= 1;
87 module_param_named(max_luns
, max_scsi_luns
, int, S_IRUGO
|S_IWUSR
);
88 MODULE_PARM_DESC(max_luns
,
89 "last scsi LUN (should be between 1 and 2^32-1)");
92 * max_scsi_report_luns: the maximum number of LUNS that will be
93 * returned from the REPORT LUNS command. 8 times this value must
94 * be allocated. In theory this could be up to an 8 byte value, but
95 * in practice, the maximum number of LUNs suppored by any device
98 static unsigned int max_scsi_report_luns
= 511;
100 module_param_named(max_report_luns
, max_scsi_report_luns
, int, S_IRUGO
|S_IWUSR
);
101 MODULE_PARM_DESC(max_report_luns
,
102 "REPORT LUNS maximum number of LUNS received (should be"
103 " between 1 and 16384)");
105 static unsigned int scsi_inq_timeout
= SCSI_TIMEOUT
/HZ
+3;
107 module_param_named(inq_timeout
, scsi_inq_timeout
, int, S_IRUGO
|S_IWUSR
);
108 MODULE_PARM_DESC(inq_timeout
,
109 "Timeout (in seconds) waiting for devices to answer INQUIRY."
110 " Default is 5. Some non-compliant devices need more.");
113 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
114 * @sreq: used to send the command
115 * @result: area to store the result of the MODE SENSE
118 * Send a vendor specific MODE SENSE (not a MODE SELECT) command using
119 * @sreq to unlock a device, storing the (unused) results into result.
120 * Called for BLIST_KEY devices.
122 static void scsi_unlock_floptical(struct scsi_request
*sreq
,
123 unsigned char *result
)
125 unsigned char scsi_cmd
[MAX_COMMAND_SIZE
];
127 printk(KERN_NOTICE
"scsi: unlocking floptical drive\n");
128 scsi_cmd
[0] = MODE_SENSE
;
132 scsi_cmd
[4] = 0x2a; /* size */
134 sreq
->sr_cmd_len
= 0;
135 sreq
->sr_data_direction
= DMA_FROM_DEVICE
;
136 scsi_wait_req(sreq
, scsi_cmd
, result
, 0x2a /* size */, SCSI_TIMEOUT
, 3);
140 * print_inquiry - printk the inquiry information
141 * @inq_result: printk this SCSI INQUIRY
144 * printk the vendor, model, and other information found in the
145 * INQUIRY data in @inq_result.
148 * Remove this, and replace with a hotplug event that logs any
149 * relevant information.
151 static void print_inquiry(unsigned char *inq_result
)
155 printk(KERN_NOTICE
" Vendor: ");
156 for (i
= 8; i
< 16; i
++)
157 if (inq_result
[i
] >= 0x20 && i
< inq_result
[4] + 5)
158 printk("%c", inq_result
[i
]);
163 for (i
= 16; i
< 32; i
++)
164 if (inq_result
[i
] >= 0x20 && i
< inq_result
[4] + 5)
165 printk("%c", inq_result
[i
]);
170 for (i
= 32; i
< 36; i
++)
171 if (inq_result
[i
] >= 0x20 && i
< inq_result
[4] + 5)
172 printk("%c", inq_result
[i
]);
178 i
= inq_result
[0] & 0x1f;
180 printk(KERN_NOTICE
" Type: %s ",
182 MAX_SCSI_DEVICE_CODE
? scsi_device_types
[i
] :
184 printk(" ANSI SCSI revision: %02x",
185 inq_result
[2] & 0x07);
186 if ((inq_result
[2] & 0x07) == 1 && (inq_result
[3] & 0x0f) == 1)
193 * scsi_alloc_sdev - allocate and setup a scsi_Device
196 * Allocate, initialize for io, and return a pointer to a scsi_Device.
197 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
198 * adds scsi_Device to the appropriate list.
201 * scsi_Device pointer, or NULL on failure.
203 static struct scsi_device
*scsi_alloc_sdev(struct scsi_target
*starget
,
204 unsigned int lun
, void *hostdata
)
206 struct scsi_device
*sdev
;
207 int display_failure_msg
= 1, ret
;
208 struct Scsi_Host
*shost
= dev_to_shost(starget
->dev
.parent
);
210 sdev
= kmalloc(sizeof(*sdev
) + shost
->transportt
->device_size
,
215 memset(sdev
, 0, sizeof(*sdev
));
216 sdev
->vendor
= scsi_null_device_strs
;
217 sdev
->model
= scsi_null_device_strs
;
218 sdev
->rev
= scsi_null_device_strs
;
220 sdev
->id
= starget
->id
;
222 sdev
->channel
= starget
->channel
;
223 sdev
->sdev_state
= SDEV_CREATED
;
224 INIT_LIST_HEAD(&sdev
->siblings
);
225 INIT_LIST_HEAD(&sdev
->same_target_siblings
);
226 INIT_LIST_HEAD(&sdev
->cmd_list
);
227 INIT_LIST_HEAD(&sdev
->starved_entry
);
228 spin_lock_init(&sdev
->list_lock
);
230 sdev
->sdev_gendev
.parent
= get_device(&starget
->dev
);
231 sdev
->sdev_target
= starget
;
233 /* usually NULL and set by ->slave_alloc instead */
234 sdev
->hostdata
= hostdata
;
236 /* if the device needs this changing, it may do so in the
237 * slave_configure function */
238 sdev
->max_device_blocked
= SCSI_DEFAULT_DEVICE_BLOCKED
;
241 * Some low level driver could use device->type
246 * Assume that the device will have handshaking problems,
247 * and then fix this field later if it turns out it
252 spin_lock_init(&sdev
->sdev_lock
);
253 sdev
->request_queue
= scsi_alloc_queue(sdev
);
254 if (!sdev
->request_queue
) {
255 /* release fn is set up in scsi_sysfs_device_initialise, so
256 * have to free and put manually here */
257 put_device(&starget
->dev
);
261 sdev
->request_queue
->queuedata
= sdev
;
262 scsi_adjust_queue_depth(sdev
, 0, sdev
->host
->cmd_per_lun
);
264 scsi_sysfs_device_initialize(sdev
);
266 if (shost
->hostt
->slave_alloc
) {
267 ret
= shost
->hostt
->slave_alloc(sdev
);
270 * if LLDD reports slave not present, don't clutter
271 * console with alloc failure messages
276 display_failure_msg
= 0;
277 goto out_device_destroy
;
284 transport_destroy_device(&sdev
->sdev_gendev
);
285 scsi_free_queue(sdev
->request_queue
);
286 put_device(&sdev
->sdev_gendev
);
288 if (display_failure_msg
)
289 printk(ALLOC_FAILURE_MSG
, __FUNCTION__
);
293 static void scsi_target_dev_release(struct device
*dev
)
295 struct device
*parent
= dev
->parent
;
296 struct scsi_target
*starget
= to_scsi_target(dev
);
301 int scsi_is_target_device(const struct device
*dev
)
303 return dev
->release
== scsi_target_dev_release
;
305 EXPORT_SYMBOL(scsi_is_target_device
);
307 static struct scsi_target
*__scsi_find_target(struct device
*parent
,
308 int channel
, uint id
)
310 struct scsi_target
*starget
, *found_starget
= NULL
;
311 struct Scsi_Host
*shost
= dev_to_shost(parent
);
313 * Search for an existing target for this sdev.
315 list_for_each_entry(starget
, &shost
->__targets
, siblings
) {
316 if (starget
->id
== id
&&
317 starget
->channel
== channel
) {
318 found_starget
= starget
;
323 get_device(&found_starget
->dev
);
325 return found_starget
;
328 static struct scsi_target
*scsi_alloc_target(struct device
*parent
,
329 int channel
, uint id
)
331 struct Scsi_Host
*shost
= dev_to_shost(parent
);
332 struct device
*dev
= NULL
;
334 const int size
= sizeof(struct scsi_target
)
335 + shost
->transportt
->target_size
;
336 struct scsi_target
*starget
= kmalloc(size
, GFP_ATOMIC
);
337 struct scsi_target
*found_target
;
340 printk(KERN_ERR
"%s: allocation failure\n", __FUNCTION__
);
343 memset(starget
, 0, size
);
345 device_initialize(dev
);
346 starget
->reap_ref
= 1;
347 dev
->parent
= get_device(parent
);
348 dev
->release
= scsi_target_dev_release
;
349 sprintf(dev
->bus_id
, "target%d:%d:%d",
350 shost
->host_no
, channel
, id
);
352 starget
->channel
= channel
;
353 INIT_LIST_HEAD(&starget
->siblings
);
354 INIT_LIST_HEAD(&starget
->devices
);
355 spin_lock_irqsave(shost
->host_lock
, flags
);
357 found_target
= __scsi_find_target(parent
, channel
, id
);
361 list_add_tail(&starget
->siblings
, &shost
->__targets
);
362 spin_unlock_irqrestore(shost
->host_lock
, flags
);
363 /* allocate and add */
364 transport_setup_device(&starget
->dev
);
365 device_add(&starget
->dev
);
366 transport_add_device(&starget
->dev
);
370 found_target
->reap_ref
++;
371 spin_unlock_irqrestore(shost
->host_lock
, flags
);
378 * scsi_target_reap - check to see if target is in use and destroy if not
380 * @starget: target to be checked
382 * This is used after removing a LUN or doing a last put of the target
383 * it checks atomically that nothing is using the target and removes
386 void scsi_target_reap(struct scsi_target
*starget
)
388 struct Scsi_Host
*shost
= dev_to_shost(starget
->dev
.parent
);
390 spin_lock_irqsave(shost
->host_lock
, flags
);
392 if (--starget
->reap_ref
== 0 && list_empty(&starget
->devices
)) {
393 list_del_init(&starget
->siblings
);
394 spin_unlock_irqrestore(shost
->host_lock
, flags
);
395 device_del(&starget
->dev
);
396 transport_unregister_device(&starget
->dev
);
397 put_device(&starget
->dev
);
400 spin_unlock_irqrestore(shost
->host_lock
, flags
);
404 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
405 * @sreq: used to send the INQUIRY
406 * @inq_result: area to store the INQUIRY result
407 * @bflags: store any bflags found here
410 * Probe the lun associated with @sreq using a standard SCSI INQUIRY;
412 * If the INQUIRY is successful, sreq->sr_result is zero and: the
413 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
414 * are copied to the Scsi_Device at @sreq->sr_device (sdev);
415 * any flags value is stored in *@bflags.
417 static void scsi_probe_lun(struct scsi_request
*sreq
, char *inq_result
,
420 struct scsi_device
*sdev
= sreq
->sr_device
; /* a bit ugly */
421 unsigned char scsi_cmd
[MAX_COMMAND_SIZE
];
422 int first_inquiry_len
, try_inquiry_len
, next_inquiry_len
;
423 int response_len
= 0;
425 struct scsi_sense_hdr sshdr
;
429 /* Perform up to 3 passes. The first pass uses a conservative
430 * transfer length of 36 unless sdev->inquiry_len specifies a
431 * different value. */
432 first_inquiry_len
= sdev
->inquiry_len
? sdev
->inquiry_len
: 36;
433 try_inquiry_len
= first_inquiry_len
;
437 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
"scsi scan: INQUIRY pass %d "
438 "to host %d channel %d id %d lun %d, length %d\n",
439 pass
, sdev
->host
->host_no
, sdev
->channel
,
440 sdev
->id
, sdev
->lun
, try_inquiry_len
));
442 /* Each pass gets up to three chances to ignore Unit Attention */
443 for (count
= 0; count
< 3; ++count
) {
444 memset(scsi_cmd
, 0, 6);
445 scsi_cmd
[0] = INQUIRY
;
446 scsi_cmd
[4] = (unsigned char) try_inquiry_len
;
447 sreq
->sr_cmd_len
= 0;
448 sreq
->sr_data_direction
= DMA_FROM_DEVICE
;
450 memset(inq_result
, 0, try_inquiry_len
);
451 scsi_wait_req(sreq
, (void *) scsi_cmd
, (void *) inq_result
,
453 HZ
/2 + HZ
*scsi_inq_timeout
, 3);
455 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
"scsi scan: INQUIRY %s "
457 sreq
->sr_result
? "failed" : "successful",
460 if (sreq
->sr_result
) {
462 * not-ready to ready transition [asc/ascq=0x28/0x0]
463 * or power-on, reset [asc/ascq=0x29/0x0], continue.
464 * INQUIRY should not yield UNIT_ATTENTION
465 * but many buggy devices do so anyway.
467 if ((driver_byte(sreq
->sr_result
) & DRIVER_SENSE
) &&
468 scsi_request_normalize_sense(sreq
, &sshdr
)) {
469 if ((sshdr
.sense_key
== UNIT_ATTENTION
) &&
470 ((sshdr
.asc
== 0x28) ||
471 (sshdr
.asc
== 0x29)) &&
479 if (sreq
->sr_result
== 0) {
480 response_len
= (unsigned char) inq_result
[4] + 5;
481 if (response_len
> 255)
482 response_len
= first_inquiry_len
; /* sanity */
485 * Get any flags for this device.
487 * XXX add a bflags to Scsi_Device, and replace the
488 * corresponding bit fields in Scsi_Device, so bflags
489 * need not be passed as an argument.
491 *bflags
= scsi_get_device_flags(sdev
, &inq_result
[8],
494 /* When the first pass succeeds we gain information about
495 * what larger transfer lengths might work. */
497 if (BLIST_INQUIRY_36
& *bflags
)
498 next_inquiry_len
= 36;
499 else if (BLIST_INQUIRY_58
& *bflags
)
500 next_inquiry_len
= 58;
501 else if (sdev
->inquiry_len
)
502 next_inquiry_len
= sdev
->inquiry_len
;
504 next_inquiry_len
= response_len
;
506 /* If more data is available perform the second pass */
507 if (next_inquiry_len
> try_inquiry_len
) {
508 try_inquiry_len
= next_inquiry_len
;
514 } else if (pass
== 2) {
515 printk(KERN_INFO
"scsi scan: %d byte inquiry failed. "
516 "Consider BLIST_INQUIRY_36 for this device\n",
519 /* If this pass failed, the third pass goes back and transfers
520 * the same amount as we successfully got in the first pass. */
521 try_inquiry_len
= first_inquiry_len
;
526 /* If the last transfer attempt got an error, assume the
527 * peripheral doesn't exist or is dead. */
531 /* Don't report any more data than the device says is valid */
532 sdev
->inquiry_len
= min(try_inquiry_len
, response_len
);
535 * XXX Abort if the response length is less than 36? If less than
536 * 32, the lookup of the device flags (above) could be invalid,
537 * and it would be possible to take an incorrect action - we do
538 * not want to hang because of a short INQUIRY. On the flip side,
539 * if the device is spun down or becoming ready (and so it gives a
540 * short INQUIRY), an abort here prevents any further use of the
541 * device, including spin up.
543 * Related to the above issue:
545 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
546 * and if not ready, sent a START_STOP to start (maybe spin up) and
547 * then send the INQUIRY again, since the INQUIRY can change after
548 * a device is initialized.
550 * Ideally, start a device if explicitly asked to do so. This
551 * assumes that a device is spun up on power on, spun down on
552 * request, and then spun up on request.
556 * The scanning code needs to know the scsi_level, even if no
557 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
558 * non-zero LUNs can be scanned.
560 sdev
->scsi_level
= inq_result
[2] & 0x07;
561 if (sdev
->scsi_level
>= 2 ||
562 (sdev
->scsi_level
== 1 && (inq_result
[3] & 0x0f) == 1))
569 * scsi_add_lun - allocate and fully initialze a Scsi_Device
570 * @sdevscan: holds information to be stored in the new Scsi_Device
571 * @sdevnew: store the address of the newly allocated Scsi_Device
572 * @inq_result: holds the result of a previous INQUIRY to the LUN
573 * @bflags: black/white list flag
576 * Allocate and initialize a Scsi_Device matching sdevscan. Optionally
577 * set fields based on values in *@bflags. If @sdevnew is not
578 * NULL, store the address of the new Scsi_Device in *@sdevnew (needed
579 * when scanning a particular LUN).
582 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
583 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
585 static int scsi_add_lun(struct scsi_device
*sdev
, char *inq_result
, int *bflags
)
588 * XXX do not save the inquiry, since it can change underneath us,
589 * save just vendor/model/rev.
591 * Rather than save it and have an ioctl that retrieves the saved
592 * value, have an ioctl that executes the same INQUIRY code used
593 * in scsi_probe_lun, let user level programs doing INQUIRY
594 * scanning run at their own risk, or supply a user level program
595 * that can correctly scan.
597 sdev
->inquiry
= kmalloc(sdev
->inquiry_len
, GFP_ATOMIC
);
598 if (sdev
->inquiry
== NULL
) {
599 return SCSI_SCAN_NO_RESPONSE
;
602 memcpy(sdev
->inquiry
, inq_result
, sdev
->inquiry_len
);
603 sdev
->vendor
= (char *) (sdev
->inquiry
+ 8);
604 sdev
->model
= (char *) (sdev
->inquiry
+ 16);
605 sdev
->rev
= (char *) (sdev
->inquiry
+ 32);
607 if (*bflags
& BLIST_ISROM
) {
609 * It would be better to modify sdev->type, and set
610 * sdev->removable, but then the print_inquiry() output
611 * would not show TYPE_ROM; if print_inquiry() is removed
612 * the issue goes away.
614 inq_result
[0] = TYPE_ROM
;
615 inq_result
[1] |= 0x80; /* removable */
616 } else if (*bflags
& BLIST_NO_ULD_ATTACH
)
617 sdev
->no_uld_attach
= 1;
619 switch (sdev
->type
= (inq_result
[0] & 0x1f)) {
626 case TYPE_MEDIUM_CHANGER
:
636 printk(KERN_INFO
"scsi: unknown device type %d\n", sdev
->type
);
639 print_inquiry(inq_result
);
642 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
643 * spec says: The device server is capable of supporting the
644 * specified peripheral device type on this logical unit. However,
645 * the physical device is not currently connected to this logical
648 * The above is vague, as it implies that we could treat 001 and
649 * 011 the same. Stay compatible with previous code, and create a
650 * Scsi_Device for a PQ of 1
652 * Don't set the device offline here; rather let the upper
653 * level drivers eval the PQ to decide whether they should
654 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
657 sdev
->inq_periph_qual
= (inq_result
[0] >> 5) & 7;
658 sdev
->removable
= (0x80 & inq_result
[1]) >> 7;
659 sdev
->lockable
= sdev
->removable
;
660 sdev
->soft_reset
= (inq_result
[7] & 1) && ((inq_result
[3] & 7) == 2);
662 if (sdev
->scsi_level
>= SCSI_3
|| (sdev
->inquiry_len
> 56 &&
663 inq_result
[56] & 0x04))
665 if (inq_result
[7] & 0x60)
667 if (inq_result
[7] & 0x10)
670 sprintf(sdev
->devfs_name
, "scsi/host%d/bus%d/target%d/lun%d",
671 sdev
->host
->host_no
, sdev
->channel
,
672 sdev
->id
, sdev
->lun
);
675 * End driverfs/devfs code.
678 if ((sdev
->scsi_level
>= SCSI_2
) && (inq_result
[7] & 2) &&
679 !(*bflags
& BLIST_NOTQ
))
680 sdev
->tagged_supported
= 1;
682 * Some devices (Texel CD ROM drives) have handshaking problems
683 * when used with the Seagate controllers. borken is initialized
684 * to 1, and then set it to 0 here.
686 if ((*bflags
& BLIST_BORKEN
) == 0)
690 * Apparently some really broken devices (contrary to the SCSI
691 * standards) need to be selected without asserting ATN
693 if (*bflags
& BLIST_SELECT_NO_ATN
)
694 sdev
->select_no_atn
= 1;
697 * Some devices may not want to have a start command automatically
698 * issued when a device is added.
700 if (*bflags
& BLIST_NOSTARTONADD
)
701 sdev
->no_start_on_add
= 1;
703 if (*bflags
& BLIST_SINGLELUN
)
704 sdev
->single_lun
= 1;
707 sdev
->use_10_for_rw
= 1;
709 if (*bflags
& BLIST_MS_SKIP_PAGE_08
)
710 sdev
->skip_ms_page_8
= 1;
712 if (*bflags
& BLIST_MS_SKIP_PAGE_3F
)
713 sdev
->skip_ms_page_3f
= 1;
715 if (*bflags
& BLIST_USE_10_BYTE_MS
)
716 sdev
->use_10_for_ms
= 1;
718 /* set the device running here so that slave configure
720 scsi_device_set_state(sdev
, SDEV_RUNNING
);
722 if (*bflags
& BLIST_MS_192_BYTES_FOR_3F
)
723 sdev
->use_192_bytes_for_3f
= 1;
725 if (*bflags
& BLIST_NOT_LOCKABLE
)
728 if (*bflags
& BLIST_RETRY_HWERROR
)
729 sdev
->retry_hwerror
= 1;
731 transport_configure_device(&sdev
->sdev_gendev
);
733 if (sdev
->host
->hostt
->slave_configure
)
734 sdev
->host
->hostt
->slave_configure(sdev
);
737 * Ok, the device is now all set up, we can
738 * register it and tell the rest of the kernel
741 scsi_sysfs_add_sdev(sdev
);
743 return SCSI_SCAN_LUN_PRESENT
;
747 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
748 * @starget: pointer to target device structure
749 * @lun: LUN of target device
750 * @sdevscan: probe the LUN corresponding to this Scsi_Device
751 * @sdevnew: store the value of any new Scsi_Device allocated
752 * @bflagsp: store bflags here if not NULL
755 * Call scsi_probe_lun, if a LUN with an attached device is found,
756 * allocate and set it up by calling scsi_add_lun.
759 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
760 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
761 * attached at the LUN
762 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
764 static int scsi_probe_and_add_lun(struct scsi_target
*starget
,
765 uint lun
, int *bflagsp
,
766 struct scsi_device
**sdevp
, int rescan
,
769 struct scsi_device
*sdev
;
770 struct scsi_request
*sreq
;
771 unsigned char *result
;
772 int bflags
, res
= SCSI_SCAN_NO_RESPONSE
;
773 struct Scsi_Host
*shost
= dev_to_shost(starget
->dev
.parent
);
776 * The rescan flag is used as an optimization, the first scan of a
777 * host adapter calls into here with rescan == 0.
780 sdev
= scsi_device_lookup_by_target(starget
, lun
);
782 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
783 "scsi scan: device exists on %s\n",
784 sdev
->sdev_gendev
.bus_id
));
788 scsi_device_put(sdev
);
791 *bflagsp
= scsi_get_device_flags(sdev
,
794 return SCSI_SCAN_LUN_PRESENT
;
798 sdev
= scsi_alloc_sdev(starget
, lun
, hostdata
);
801 sreq
= scsi_allocate_request(sdev
, GFP_ATOMIC
);
804 result
= kmalloc(256, GFP_ATOMIC
|
805 (shost
->unchecked_isa_dma
) ? __GFP_DMA
: 0);
809 scsi_probe_lun(sreq
, result
, &bflags
);
811 goto out_free_result
;
814 * result contains valid SCSI INQUIRY data.
816 if ((result
[0] >> 5) == 3) {
818 * For a Peripheral qualifier 3 (011b), the SCSI
819 * spec says: The device server is not capable of
820 * supporting a physical device on this logical
823 * For disks, this implies that there is no
824 * logical disk configured at sdev->lun, but there
825 * is a target id responding.
827 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
828 "scsi scan: peripheral qualifier of 3,"
829 " no device added\n"));
830 res
= SCSI_SCAN_TARGET_PRESENT
;
831 goto out_free_result
;
834 res
= scsi_add_lun(sdev
, result
, &bflags
);
835 if (res
== SCSI_SCAN_LUN_PRESENT
) {
836 if (bflags
& BLIST_KEY
) {
838 scsi_unlock_floptical(sreq
, result
);
847 scsi_release_request(sreq
);
849 if (res
== SCSI_SCAN_LUN_PRESENT
) {
851 scsi_device_get(sdev
);
855 if (sdev
->host
->hostt
->slave_destroy
)
856 sdev
->host
->hostt
->slave_destroy(sdev
);
857 transport_destroy_device(&sdev
->sdev_gendev
);
858 put_device(&sdev
->sdev_gendev
);
865 * scsi_sequential_lun_scan - sequentially scan a SCSI target
866 * @starget: pointer to target structure to scan
867 * @bflags: black/white list flag for LUN 0
868 * @lun0_res: result of scanning LUN 0
871 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
872 * scanned) to some maximum lun until a LUN is found with no device
873 * attached. Use the bflags to figure out any oddities.
875 * Modifies sdevscan->lun.
877 static void scsi_sequential_lun_scan(struct scsi_target
*starget
,
878 int bflags
, int lun0_res
, int scsi_level
,
881 unsigned int sparse_lun
, lun
, max_dev_lun
;
882 struct Scsi_Host
*shost
= dev_to_shost(starget
->dev
.parent
);
884 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
"scsi scan: Sequential scan of"
885 "%s\n", starget
->dev
.bus_id
));
887 max_dev_lun
= min(max_scsi_luns
, shost
->max_lun
);
889 * If this device is known to support sparse multiple units,
890 * override the other settings, and scan all of them. Normally,
891 * SCSI-3 devices should be scanned via the REPORT LUNS.
893 if (bflags
& BLIST_SPARSELUN
) {
894 max_dev_lun
= shost
->max_lun
;
900 * If not sparse lun and no device attached at LUN 0 do not scan
903 if (!sparse_lun
&& (lun0_res
!= SCSI_SCAN_LUN_PRESENT
))
907 * If less than SCSI_1_CSS, and no special lun scaning, stop
908 * scanning; this matches 2.4 behaviour, but could just be a bug
909 * (to continue scanning a SCSI_1_CSS device).
911 * This test is broken. We might not have any device on lun0 for
912 * a sparselun device, and if that's the case then how would we
913 * know the real scsi_level, eh? It might make sense to just not
914 * scan any SCSI_1 device for non-0 luns, but that check would best
915 * go into scsi_alloc_sdev() and just have it return null when asked
916 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
918 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
919 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
924 * If this device is known to support multiple units, override
925 * the other settings, and scan all of them.
927 if (bflags
& BLIST_FORCELUN
)
928 max_dev_lun
= shost
->max_lun
;
930 * REGAL CDC-4X: avoid hang after LUN 4
932 if (bflags
& BLIST_MAX5LUN
)
933 max_dev_lun
= min(5U, max_dev_lun
);
935 * Do not scan SCSI-2 or lower device past LUN 7, unless
938 if (scsi_level
< SCSI_3
&& !(bflags
& BLIST_LARGELUN
))
939 max_dev_lun
= min(8U, max_dev_lun
);
942 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
943 * until we reach the max, or no LUN is found and we are not
946 for (lun
= 1; lun
< max_dev_lun
; ++lun
)
947 if ((scsi_probe_and_add_lun(starget
, lun
, NULL
, NULL
, rescan
,
948 NULL
) != SCSI_SCAN_LUN_PRESENT
) &&
954 * scsilun_to_int: convert a scsi_lun to an int
955 * @scsilun: struct scsi_lun to be converted.
958 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
959 * integer, and return the result. The caller must check for
960 * truncation before using this function.
963 * The struct scsi_lun is assumed to be four levels, with each level
964 * effectively containing a SCSI byte-ordered (big endian) short; the
965 * addressing bits of each level are ignored (the highest two bits).
966 * For a description of the LUN format, post SCSI-3 see the SCSI
967 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
969 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
970 * the integer: 0x0b030a04
972 static int scsilun_to_int(struct scsi_lun
*scsilun
)
978 for (i
= 0; i
< sizeof(lun
); i
+= 2)
979 lun
= lun
| (((scsilun
->scsi_lun
[i
] << 8) |
980 scsilun
->scsi_lun
[i
+ 1]) << (i
* 8));
985 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
986 * @sdevscan: scan the host, channel, and id of this Scsi_Device
989 * If @sdevscan is for a SCSI-3 or up device, send a REPORT LUN
990 * command, and scan the resulting list of LUNs by calling
991 * scsi_probe_and_add_lun.
993 * Modifies sdevscan->lun.
996 * 0: scan completed (or no memory, so further scanning is futile)
997 * 1: no report lun scan, or not configured
999 static int scsi_report_lun_scan(struct scsi_device
*sdev
, int bflags
,
1003 unsigned char scsi_cmd
[MAX_COMMAND_SIZE
];
1004 unsigned int length
;
1006 unsigned int num_luns
;
1007 unsigned int retries
;
1008 struct scsi_lun
*lunp
, *lun_data
;
1009 struct scsi_request
*sreq
;
1011 struct scsi_sense_hdr sshdr
;
1012 struct scsi_target
*starget
= scsi_target(sdev
);
1015 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1016 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1017 * support more than 8 LUNs.
1019 if ((bflags
& BLIST_NOREPORTLUN
) ||
1020 sdev
->scsi_level
< SCSI_2
||
1021 (sdev
->scsi_level
< SCSI_3
&&
1022 (!(bflags
& BLIST_REPORTLUN2
) || sdev
->host
->max_lun
<= 8)) )
1024 if (bflags
& BLIST_NOLUN
)
1027 sreq
= scsi_allocate_request(sdev
, GFP_ATOMIC
);
1031 sprintf(devname
, "host %d channel %d id %d",
1032 sdev
->host
->host_no
, sdev
->channel
, sdev
->id
);
1035 * Allocate enough to hold the header (the same size as one scsi_lun)
1036 * plus the max number of luns we are requesting.
1038 * Reallocating and trying again (with the exact amount we need)
1039 * would be nice, but then we need to somehow limit the size
1040 * allocated based on the available memory and the limits of
1041 * kmalloc - we don't want a kmalloc() failure of a huge value to
1042 * prevent us from finding any LUNs on this target.
1044 length
= (max_scsi_report_luns
+ 1) * sizeof(struct scsi_lun
);
1045 lun_data
= kmalloc(length
, GFP_ATOMIC
|
1046 (sdev
->host
->unchecked_isa_dma
? __GFP_DMA
: 0));
1048 goto out_release_request
;
1050 scsi_cmd
[0] = REPORT_LUNS
;
1053 * bytes 1 - 5: reserved, set to zero.
1055 memset(&scsi_cmd
[1], 0, 5);
1058 * bytes 6 - 9: length of the command.
1060 scsi_cmd
[6] = (unsigned char) (length
>> 24) & 0xff;
1061 scsi_cmd
[7] = (unsigned char) (length
>> 16) & 0xff;
1062 scsi_cmd
[8] = (unsigned char) (length
>> 8) & 0xff;
1063 scsi_cmd
[9] = (unsigned char) length
& 0xff;
1065 scsi_cmd
[10] = 0; /* reserved */
1066 scsi_cmd
[11] = 0; /* control */
1067 sreq
->sr_cmd_len
= 0;
1068 sreq
->sr_data_direction
= DMA_FROM_DEVICE
;
1071 * We can get a UNIT ATTENTION, for example a power on/reset, so
1072 * retry a few times (like sd.c does for TEST UNIT READY).
1073 * Experience shows some combinations of adapter/devices get at
1074 * least two power on/resets.
1076 * Illegal requests (for devices that do not support REPORT LUNS)
1077 * should come through as a check condition, and will not generate
1080 for (retries
= 0; retries
< 3; retries
++) {
1081 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO
"scsi scan: Sending"
1082 " REPORT LUNS to %s (try %d)\n", devname
,
1084 scsi_wait_req(sreq
, scsi_cmd
, lun_data
, length
,
1085 SCSI_TIMEOUT
+ 4*HZ
, 3);
1086 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO
"scsi scan: REPORT LUNS"
1087 " %s (try %d) result 0x%x\n", sreq
->sr_result
1088 ? "failed" : "successful", retries
,
1090 if (sreq
->sr_result
== 0)
1092 else if (scsi_request_normalize_sense(sreq
, &sshdr
)) {
1093 if (sshdr
.sense_key
!= UNIT_ATTENTION
)
1098 if (sreq
->sr_result
) {
1100 * The device probably does not support a REPORT LUN command
1103 scsi_release_request(sreq
);
1106 scsi_release_request(sreq
);
1109 * Get the length from the first four bytes of lun_data.
1111 data
= (u8
*) lun_data
->scsi_lun
;
1112 length
= ((data
[0] << 24) | (data
[1] << 16) |
1113 (data
[2] << 8) | (data
[3] << 0));
1115 num_luns
= (length
/ sizeof(struct scsi_lun
));
1116 if (num_luns
> max_scsi_report_luns
) {
1117 printk(KERN_WARNING
"scsi: On %s only %d (max_scsi_report_luns)"
1118 " of %d luns reported, try increasing"
1119 " max_scsi_report_luns.\n", devname
,
1120 max_scsi_report_luns
, num_luns
);
1121 num_luns
= max_scsi_report_luns
;
1124 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO
"scsi scan: REPORT LUN scan of"
1125 " host %d channel %d id %d\n", sdev
->host
->host_no
,
1126 sdev
->channel
, sdev
->id
));
1129 * Scan the luns in lun_data. The entry at offset 0 is really
1130 * the header, so start at 1 and go up to and including num_luns.
1132 for (lunp
= &lun_data
[1]; lunp
<= &lun_data
[num_luns
]; lunp
++) {
1133 lun
= scsilun_to_int(lunp
);
1136 * Check if the unused part of lunp is non-zero, and so
1137 * does not fit in lun.
1139 if (memcmp(&lunp
->scsi_lun
[sizeof(lun
)], "\0\0\0\0", 4)) {
1143 * Output an error displaying the LUN in byte order,
1144 * this differs from what linux would print for the
1145 * integer LUN value.
1147 printk(KERN_WARNING
"scsi: %s lun 0x", devname
);
1148 data
= (char *)lunp
->scsi_lun
;
1149 for (i
= 0; i
< sizeof(struct scsi_lun
); i
++)
1150 printk("%02x", data
[i
]);
1151 printk(" has a LUN larger than currently supported.\n");
1152 } else if (lun
== 0) {
1154 * LUN 0 has already been scanned.
1156 } else if (lun
> sdev
->host
->max_lun
) {
1157 printk(KERN_WARNING
"scsi: %s lun%d has a LUN larger"
1158 " than allowed by the host adapter\n",
1163 res
= scsi_probe_and_add_lun(starget
,
1164 lun
, NULL
, NULL
, rescan
, NULL
);
1165 if (res
== SCSI_SCAN_NO_RESPONSE
) {
1167 * Got some results, but now none, abort.
1169 printk(KERN_ERR
"scsi: Unexpected response"
1170 " from %s lun %d while scanning, scan"
1171 " aborted\n", devname
, lun
);
1180 out_release_request
:
1181 scsi_release_request(sreq
);
1184 * We are out of memory, don't try scanning any further.
1186 printk(ALLOC_FAILURE_MSG
, __FUNCTION__
);
1190 struct scsi_device
*__scsi_add_device(struct Scsi_Host
*shost
, uint channel
,
1191 uint id
, uint lun
, void *hostdata
)
1193 struct scsi_device
*sdev
;
1194 struct device
*parent
= &shost
->shost_gendev
;
1196 struct scsi_target
*starget
= scsi_alloc_target(parent
, channel
, id
);
1199 return ERR_PTR(-ENOMEM
);
1201 down(&shost
->scan_mutex
);
1202 res
= scsi_probe_and_add_lun(starget
, lun
, NULL
, &sdev
, 1, hostdata
);
1203 if (res
!= SCSI_SCAN_LUN_PRESENT
)
1204 sdev
= ERR_PTR(-ENODEV
);
1205 up(&shost
->scan_mutex
);
1206 scsi_target_reap(starget
);
1207 put_device(&starget
->dev
);
1211 EXPORT_SYMBOL(__scsi_add_device
);
1213 void scsi_rescan_device(struct device
*dev
)
1215 struct scsi_driver
*drv
;
1220 drv
= to_scsi_driver(dev
->driver
);
1221 if (try_module_get(drv
->owner
)) {
1224 module_put(drv
->owner
);
1227 EXPORT_SYMBOL(scsi_rescan_device
);
1230 * scsi_scan_target - scan a target id, possibly including all LUNs on the
1232 * @sdevsca: Scsi_Device handle for scanning
1233 * @shost: host to scan
1234 * @channel: channel to scan
1235 * @id: target id to scan
1238 * Scan the target id on @shost, @channel, and @id. Scan at least LUN
1239 * 0, and possibly all LUNs on the target id.
1241 * Use the pre-allocated @sdevscan as a handle for the scanning. This
1242 * function sets sdevscan->host, sdevscan->id and sdevscan->lun; the
1243 * scanning functions modify sdevscan->lun.
1245 * First try a REPORT LUN scan, if that does not scan the target, do a
1246 * sequential scan of LUNs on the target id.
1248 void scsi_scan_target(struct device
*parent
, unsigned int channel
,
1249 unsigned int id
, unsigned int lun
, int rescan
)
1251 struct Scsi_Host
*shost
= dev_to_shost(parent
);
1254 struct scsi_device
*sdev
= NULL
;
1255 struct scsi_target
*starget
;
1257 if (shost
->this_id
== id
)
1259 * Don't scan the host adapter
1264 starget
= scsi_alloc_target(parent
, channel
, id
);
1269 get_device(&starget
->dev
);
1270 if (lun
!= SCAN_WILD_CARD
) {
1272 * Scan for a specific host/chan/id/lun.
1274 scsi_probe_and_add_lun(starget
, lun
, NULL
, NULL
, rescan
, NULL
);
1279 * Scan LUN 0, if there is some response, scan further. Ideally, we
1280 * would not configure LUN 0 until all LUNs are scanned.
1282 res
= scsi_probe_and_add_lun(starget
, 0, &bflags
, &sdev
, rescan
, NULL
);
1283 if (res
== SCSI_SCAN_LUN_PRESENT
) {
1284 if (scsi_report_lun_scan(sdev
, bflags
, rescan
) != 0)
1286 * The REPORT LUN did not scan the target,
1287 * do a sequential scan.
1289 scsi_sequential_lun_scan(starget
, bflags
,
1290 res
, sdev
->scsi_level
, rescan
);
1291 } else if (res
== SCSI_SCAN_TARGET_PRESENT
) {
1293 * There's a target here, but lun 0 is offline so we
1294 * can't use the report_lun scan. Fall back to a
1295 * sequential lun scan with a bflags of SPARSELUN and
1296 * a default scsi level of SCSI_2
1298 scsi_sequential_lun_scan(starget
, BLIST_SPARSELUN
,
1299 SCSI_SCAN_TARGET_PRESENT
, SCSI_2
, rescan
);
1302 scsi_device_put(sdev
);
1305 /* now determine if the target has any children at all
1306 * and if not, nuke it */
1307 scsi_target_reap(starget
);
1309 put_device(&starget
->dev
);
1311 EXPORT_SYMBOL(scsi_scan_target
);
1313 static void scsi_scan_channel(struct Scsi_Host
*shost
, unsigned int channel
,
1314 unsigned int id
, unsigned int lun
, int rescan
)
1318 if (id
== SCAN_WILD_CARD
)
1319 for (id
= 0; id
< shost
->max_id
; ++id
) {
1321 * XXX adapter drivers when possible (FCP, iSCSI)
1322 * could modify max_id to match the current max,
1323 * not the absolute max.
1325 * XXX add a shost id iterator, so for example,
1326 * the FC ID can be the same as a target id
1327 * without a huge overhead of sparse id's.
1329 if (shost
->reverse_ordering
)
1331 * Scan from high to low id.
1333 order_id
= shost
->max_id
- id
- 1;
1336 scsi_scan_target(&shost
->shost_gendev
, channel
, order_id
, lun
, rescan
);
1339 scsi_scan_target(&shost
->shost_gendev
, channel
, id
, lun
, rescan
);
1342 int scsi_scan_host_selected(struct Scsi_Host
*shost
, unsigned int channel
,
1343 unsigned int id
, unsigned int lun
, int rescan
)
1345 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO
"%s: <%u:%u:%u:%u>\n",
1346 __FUNCTION__
, shost
->host_no
, channel
, id
, lun
));
1348 if (((channel
!= SCAN_WILD_CARD
) && (channel
> shost
->max_channel
)) ||
1349 ((id
!= SCAN_WILD_CARD
) && (id
> shost
->max_id
)) ||
1350 ((lun
!= SCAN_WILD_CARD
) && (lun
> shost
->max_lun
)))
1353 down(&shost
->scan_mutex
);
1354 if (channel
== SCAN_WILD_CARD
)
1355 for (channel
= 0; channel
<= shost
->max_channel
; channel
++)
1356 scsi_scan_channel(shost
, channel
, id
, lun
, rescan
);
1358 scsi_scan_channel(shost
, channel
, id
, lun
, rescan
);
1359 up(&shost
->scan_mutex
);
1365 * scsi_scan_host - scan the given adapter
1366 * @shost: adapter to scan
1368 void scsi_scan_host(struct Scsi_Host
*shost
)
1370 scsi_scan_host_selected(shost
, SCAN_WILD_CARD
, SCAN_WILD_CARD
,
1373 EXPORT_SYMBOL(scsi_scan_host
);
1376 * scsi_scan_single_target - scan the given SCSI target
1377 * @shost: adapter to scan
1378 * @chan: channel to scan
1379 * @id: target id to scan
1381 void scsi_scan_single_target(struct Scsi_Host
*shost
,
1382 unsigned int chan
, unsigned int id
)
1384 scsi_scan_host_selected(shost
, chan
, id
, SCAN_WILD_CARD
, 1);
1386 EXPORT_SYMBOL(scsi_scan_single_target
);
1388 void scsi_forget_host(struct Scsi_Host
*shost
)
1390 struct scsi_target
*starget
, *tmp
;
1391 unsigned long flags
;
1394 * Ok, this look a bit strange. We always look for the first device
1395 * on the list as scsi_remove_device removes them from it - thus we
1396 * also have to release the lock.
1397 * We don't need to get another reference to the device before
1398 * releasing the lock as we already own the reference from
1399 * scsi_register_device that's release in scsi_remove_device. And
1400 * after that we don't look at sdev anymore.
1402 spin_lock_irqsave(shost
->host_lock
, flags
);
1403 list_for_each_entry_safe(starget
, tmp
, &shost
->__targets
, siblings
) {
1404 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1405 scsi_remove_target(&starget
->dev
);
1406 spin_lock_irqsave(shost
->host_lock
, flags
);
1408 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1412 * Function: scsi_get_host_dev()
1414 * Purpose: Create a Scsi_Device that points to the host adapter itself.
1416 * Arguments: SHpnt - Host that needs a Scsi_Device
1418 * Lock status: None assumed.
1420 * Returns: The Scsi_Device or NULL
1423 * Attach a single Scsi_Device to the Scsi_Host - this should
1424 * be made to look like a "pseudo-device" that points to the
1427 * Note - this device is not accessible from any high-level
1428 * drivers (including generics), which is probably not
1429 * optimal. We can add hooks later to attach
1431 struct scsi_device
*scsi_get_host_dev(struct Scsi_Host
*shost
)
1433 struct scsi_device
*sdev
;
1434 struct scsi_target
*starget
;
1436 starget
= scsi_alloc_target(&shost
->shost_gendev
, 0, shost
->this_id
);
1440 sdev
= scsi_alloc_sdev(starget
, 0, NULL
);
1442 sdev
->sdev_gendev
.parent
= get_device(&starget
->dev
);
1445 put_device(&starget
->dev
);
1448 EXPORT_SYMBOL(scsi_get_host_dev
);
1451 * Function: scsi_free_host_dev()
1453 * Purpose: Free a scsi_device that points to the host adapter itself.
1455 * Arguments: SHpnt - Host that needs a Scsi_Device
1457 * Lock status: None assumed.
1463 void scsi_free_host_dev(struct scsi_device
*sdev
)
1465 BUG_ON(sdev
->id
!= sdev
->host
->this_id
);
1467 if (sdev
->host
->hostt
->slave_destroy
)
1468 sdev
->host
->hostt
->slave_destroy(sdev
);
1469 transport_destroy_device(&sdev
->sdev_gendev
);
1470 put_device(&sdev
->sdev_gendev
);
1472 EXPORT_SYMBOL(scsi_free_host_dev
);