blob: cca772624ae701ea8278ce770c10c8617e710c5e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * scsi_scan.c
3 *
4 * Copyright (C) 2000 Eric Youngdale,
5 * Copyright (C) 2002 Patrick Mansfield
6 *
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.
10 *
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.
13 *
14 * For every id of every channel on the given host:
15 *
16 * Scan LUN 0; if the target responds to LUN 0 (even if there is no
17 * device or storage attached to LUN 0):
18 *
19 * If LUN 0 has a device attached, allocate and setup a
20 * Scsi_Device for it.
21 *
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.
26 */
27
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>
34
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>
43
44#include "scsi_priv.h"
45#include "scsi_logging.h"
46
47#define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
48 " SCSI scanning, some SCSI devices might not be configured\n"
49
50/*
51 * Default timeout
52 */
53#define SCSI_TIMEOUT (2*HZ)
54
55/*
56 * Prefix values for the SCSI id's (stored in driverfs name field)
57 */
58#define SCSI_UID_SER_NUM 'S'
59#define SCSI_UID_UNKNOWN 'Z'
60
61/*
62 * Return values of some of the scanning functions.
63 *
64 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
65 * includes allocation or general failures preventing IO from being sent.
66 *
67 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
68 * on the given LUN.
69 *
70 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
71 * given LUN.
72 */
73#define SCSI_SCAN_NO_RESPONSE 0
74#define SCSI_SCAN_TARGET_PRESENT 1
75#define SCSI_SCAN_LUN_PRESENT 2
76
77static char *scsi_null_device_strs = "nullnullnullnull";
78
79#define MAX_SCSI_LUNS 512
80
81#ifdef CONFIG_SCSI_MULTI_LUN
82static unsigned int max_scsi_luns = MAX_SCSI_LUNS;
83#else
84static unsigned int max_scsi_luns = 1;
85#endif
86
87module_param_named(max_luns, max_scsi_luns, int, S_IRUGO|S_IWUSR);
88MODULE_PARM_DESC(max_luns,
89 "last scsi LUN (should be between 1 and 2^32-1)");
90
91/*
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
96 * is about 16k.
97 */
98static unsigned int max_scsi_report_luns = 511;
99
100module_param_named(max_report_luns, max_scsi_report_luns, int, S_IRUGO|S_IWUSR);
101MODULE_PARM_DESC(max_report_luns,
102 "REPORT LUNS maximum number of LUNS received (should be"
103 " between 1 and 16384)");
104
105static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ+3;
106
107module_param_named(inq_timeout, scsi_inq_timeout, int, S_IRUGO|S_IWUSR);
108MODULE_PARM_DESC(inq_timeout,
109 "Timeout (in seconds) waiting for devices to answer INQUIRY."
110 " Default is 5. Some non-compliant devices need more.");
111
112/**
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
116 *
117 * Description:
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.
121 **/
122static void scsi_unlock_floptical(struct scsi_request *sreq,
123 unsigned char *result)
124{
125 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
126
127 printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
128 scsi_cmd[0] = MODE_SENSE;
129 scsi_cmd[1] = 0;
130 scsi_cmd[2] = 0x2e;
131 scsi_cmd[3] = 0;
132 scsi_cmd[4] = 0x2a; /* size */
133 scsi_cmd[5] = 0;
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);
137}
138
139/**
140 * print_inquiry - printk the inquiry information
141 * @inq_result: printk this SCSI INQUIRY
142 *
143 * Description:
144 * printk the vendor, model, and other information found in the
145 * INQUIRY data in @inq_result.
146 *
147 * Notes:
148 * Remove this, and replace with a hotplug event that logs any
149 * relevant information.
150 **/
151static void print_inquiry(unsigned char *inq_result)
152{
153 int i;
154
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]);
159 else
160 printk(" ");
161
162 printk(" Model: ");
163 for (i = 16; i < 32; i++)
164 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
165 printk("%c", inq_result[i]);
166 else
167 printk(" ");
168
169 printk(" Rev: ");
170 for (i = 32; i < 36; i++)
171 if (inq_result[i] >= 0x20 && i < inq_result[4] + 5)
172 printk("%c", inq_result[i]);
173 else
174 printk(" ");
175
176 printk("\n");
177
178 i = inq_result[0] & 0x1f;
179
180 printk(KERN_NOTICE " Type: %s ",
181 i <
182 MAX_SCSI_DEVICE_CODE ? scsi_device_types[i] :
183 "Unknown ");
184 printk(" ANSI SCSI revision: %02x",
185 inq_result[2] & 0x07);
186 if ((inq_result[2] & 0x07) == 1 && (inq_result[3] & 0x0f) == 1)
187 printk(" CCS\n");
188 else
189 printk("\n");
190}
191
192/**
193 * scsi_alloc_sdev - allocate and setup a scsi_Device
194 *
195 * Description:
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.
199 *
200 * Return value:
201 * scsi_Device pointer, or NULL on failure.
202 **/
203static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
204 unsigned int lun, void *hostdata)
205{
206 struct scsi_device *sdev;
207 int display_failure_msg = 1, ret;
208 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
209
210 sdev = kmalloc(sizeof(*sdev) + shost->transportt->device_size,
211 GFP_ATOMIC);
212 if (!sdev)
213 goto out;
214
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;
219 sdev->host = shost;
220 sdev->id = starget->id;
221 sdev->lun = lun;
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);
229
230 sdev->sdev_gendev.parent = get_device(&starget->dev);
231 sdev->sdev_target = starget;
232
233 /* usually NULL and set by ->slave_alloc instead */
234 sdev->hostdata = hostdata;
235
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;
239
240 /*
241 * Some low level driver could use device->type
242 */
243 sdev->type = -1;
244
245 /*
246 * Assume that the device will have handshaking problems,
247 * and then fix this field later if it turns out it
248 * doesn't
249 */
250 sdev->borken = 1;
251
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 sdev->request_queue = scsi_alloc_queue(sdev);
253 if (!sdev->request_queue) {
254 /* release fn is set up in scsi_sysfs_device_initialise, so
255 * have to free and put manually here */
256 put_device(&starget->dev);
257 goto out;
258 }
259
260 sdev->request_queue->queuedata = sdev;
261 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
262
263 scsi_sysfs_device_initialize(sdev);
264
265 if (shost->hostt->slave_alloc) {
266 ret = shost->hostt->slave_alloc(sdev);
267 if (ret) {
268 /*
269 * if LLDD reports slave not present, don't clutter
270 * console with alloc failure messages
271
272
273 */
274 if (ret == -ENXIO)
275 display_failure_msg = 0;
276 goto out_device_destroy;
277 }
278 }
279
280 return sdev;
281
282out_device_destroy:
283 transport_destroy_device(&sdev->sdev_gendev);
284 scsi_free_queue(sdev->request_queue);
285 put_device(&sdev->sdev_gendev);
286out:
287 if (display_failure_msg)
288 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
289 return NULL;
290}
291
292static void scsi_target_dev_release(struct device *dev)
293{
294 struct device *parent = dev->parent;
295 struct scsi_target *starget = to_scsi_target(dev);
296 kfree(starget);
297 put_device(parent);
298}
299
300int scsi_is_target_device(const struct device *dev)
301{
302 return dev->release == scsi_target_dev_release;
303}
304EXPORT_SYMBOL(scsi_is_target_device);
305
306static struct scsi_target *__scsi_find_target(struct device *parent,
307 int channel, uint id)
308{
309 struct scsi_target *starget, *found_starget = NULL;
310 struct Scsi_Host *shost = dev_to_shost(parent);
311 /*
312 * Search for an existing target for this sdev.
313 */
314 list_for_each_entry(starget, &shost->__targets, siblings) {
315 if (starget->id == id &&
316 starget->channel == channel) {
317 found_starget = starget;
318 break;
319 }
320 }
321 if (found_starget)
322 get_device(&found_starget->dev);
323
324 return found_starget;
325}
326
327static struct scsi_target *scsi_alloc_target(struct device *parent,
328 int channel, uint id)
329{
330 struct Scsi_Host *shost = dev_to_shost(parent);
331 struct device *dev = NULL;
332 unsigned long flags;
333 const int size = sizeof(struct scsi_target)
334 + shost->transportt->target_size;
335 struct scsi_target *starget = kmalloc(size, GFP_ATOMIC);
336 struct scsi_target *found_target;
337
338 if (!starget) {
339 printk(KERN_ERR "%s: allocation failure\n", __FUNCTION__);
340 return NULL;
341 }
342 memset(starget, 0, size);
343 dev = &starget->dev;
344 device_initialize(dev);
345 starget->reap_ref = 1;
346 dev->parent = get_device(parent);
347 dev->release = scsi_target_dev_release;
348 sprintf(dev->bus_id, "target%d:%d:%d",
349 shost->host_no, channel, id);
350 starget->id = id;
351 starget->channel = channel;
352 INIT_LIST_HEAD(&starget->siblings);
353 INIT_LIST_HEAD(&starget->devices);
354 spin_lock_irqsave(shost->host_lock, flags);
355
356 found_target = __scsi_find_target(parent, channel, id);
357 if (found_target)
358 goto found;
359
360 list_add_tail(&starget->siblings, &shost->__targets);
361 spin_unlock_irqrestore(shost->host_lock, flags);
362 /* allocate and add */
363 transport_setup_device(&starget->dev);
364 device_add(&starget->dev);
365 transport_add_device(&starget->dev);
366 return starget;
367
368 found:
369 found_target->reap_ref++;
370 spin_unlock_irqrestore(shost->host_lock, flags);
371 put_device(parent);
372 kfree(starget);
373 return found_target;
374}
375
376/**
377 * scsi_target_reap - check to see if target is in use and destroy if not
378 *
379 * @starget: target to be checked
380 *
381 * This is used after removing a LUN or doing a last put of the target
382 * it checks atomically that nothing is using the target and removes
383 * it if so.
384 */
385void scsi_target_reap(struct scsi_target *starget)
386{
387 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
388 unsigned long flags;
389 spin_lock_irqsave(shost->host_lock, flags);
390
391 if (--starget->reap_ref == 0 && list_empty(&starget->devices)) {
392 list_del_init(&starget->siblings);
393 spin_unlock_irqrestore(shost->host_lock, flags);
394 device_del(&starget->dev);
395 transport_unregister_device(&starget->dev);
396 put_device(&starget->dev);
397 return;
398 }
399 spin_unlock_irqrestore(shost->host_lock, flags);
400}
401
402/**
403 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
404 * @sreq: used to send the INQUIRY
405 * @inq_result: area to store the INQUIRY result
406 * @bflags: store any bflags found here
407 *
408 * Description:
409 * Probe the lun associated with @sreq using a standard SCSI INQUIRY;
410 *
411 * If the INQUIRY is successful, sreq->sr_result is zero and: the
412 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
413 * are copied to the Scsi_Device at @sreq->sr_device (sdev);
414 * any flags value is stored in *@bflags.
415 **/
416static void scsi_probe_lun(struct scsi_request *sreq, char *inq_result,
417 int *bflags)
418{
419 struct scsi_device *sdev = sreq->sr_device; /* a bit ugly */
420 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
421 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
422 int response_len = 0;
423 int pass, count;
424 struct scsi_sense_hdr sshdr;
425
426 *bflags = 0;
427
428 /* Perform up to 3 passes. The first pass uses a conservative
429 * transfer length of 36 unless sdev->inquiry_len specifies a
430 * different value. */
431 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
432 try_inquiry_len = first_inquiry_len;
433 pass = 1;
434
435 next_pass:
436 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY pass %d "
437 "to host %d channel %d id %d lun %d, length %d\n",
438 pass, sdev->host->host_no, sdev->channel,
439 sdev->id, sdev->lun, try_inquiry_len));
440
441 /* Each pass gets up to three chances to ignore Unit Attention */
442 for (count = 0; count < 3; ++count) {
443 memset(scsi_cmd, 0, 6);
444 scsi_cmd[0] = INQUIRY;
445 scsi_cmd[4] = (unsigned char) try_inquiry_len;
446 sreq->sr_cmd_len = 0;
447 sreq->sr_data_direction = DMA_FROM_DEVICE;
448
449 memset(inq_result, 0, try_inquiry_len);
450 scsi_wait_req(sreq, (void *) scsi_cmd, (void *) inq_result,
451 try_inquiry_len,
452 HZ/2 + HZ*scsi_inq_timeout, 3);
453
454 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s "
455 "with code 0x%x\n",
456 sreq->sr_result ? "failed" : "successful",
457 sreq->sr_result));
458
459 if (sreq->sr_result) {
460 /*
461 * not-ready to ready transition [asc/ascq=0x28/0x0]
462 * or power-on, reset [asc/ascq=0x29/0x0], continue.
463 * INQUIRY should not yield UNIT_ATTENTION
464 * but many buggy devices do so anyway.
465 */
466 if ((driver_byte(sreq->sr_result) & DRIVER_SENSE) &&
467 scsi_request_normalize_sense(sreq, &sshdr)) {
468 if ((sshdr.sense_key == UNIT_ATTENTION) &&
469 ((sshdr.asc == 0x28) ||
470 (sshdr.asc == 0x29)) &&
471 (sshdr.ascq == 0))
472 continue;
473 }
474 }
475 break;
476 }
477
478 if (sreq->sr_result == 0) {
479 response_len = (unsigned char) inq_result[4] + 5;
480 if (response_len > 255)
481 response_len = first_inquiry_len; /* sanity */
482
483 /*
484 * Get any flags for this device.
485 *
486 * XXX add a bflags to Scsi_Device, and replace the
487 * corresponding bit fields in Scsi_Device, so bflags
488 * need not be passed as an argument.
489 */
490 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
491 &inq_result[16]);
492
493 /* When the first pass succeeds we gain information about
494 * what larger transfer lengths might work. */
495 if (pass == 1) {
496 if (BLIST_INQUIRY_36 & *bflags)
497 next_inquiry_len = 36;
498 else if (BLIST_INQUIRY_58 & *bflags)
499 next_inquiry_len = 58;
500 else if (sdev->inquiry_len)
501 next_inquiry_len = sdev->inquiry_len;
502 else
503 next_inquiry_len = response_len;
504
505 /* If more data is available perform the second pass */
506 if (next_inquiry_len > try_inquiry_len) {
507 try_inquiry_len = next_inquiry_len;
508 pass = 2;
509 goto next_pass;
510 }
511 }
512
513 } else if (pass == 2) {
514 printk(KERN_INFO "scsi scan: %d byte inquiry failed. "
515 "Consider BLIST_INQUIRY_36 for this device\n",
516 try_inquiry_len);
517
518 /* If this pass failed, the third pass goes back and transfers
519 * the same amount as we successfully got in the first pass. */
520 try_inquiry_len = first_inquiry_len;
521 pass = 3;
522 goto next_pass;
523 }
524
525 /* If the last transfer attempt got an error, assume the
526 * peripheral doesn't exist or is dead. */
527 if (sreq->sr_result)
528 return;
529
530 /* Don't report any more data than the device says is valid */
531 sdev->inquiry_len = min(try_inquiry_len, response_len);
532
533 /*
534 * XXX Abort if the response length is less than 36? If less than
535 * 32, the lookup of the device flags (above) could be invalid,
536 * and it would be possible to take an incorrect action - we do
537 * not want to hang because of a short INQUIRY. On the flip side,
538 * if the device is spun down or becoming ready (and so it gives a
539 * short INQUIRY), an abort here prevents any further use of the
540 * device, including spin up.
541 *
542 * Related to the above issue:
543 *
544 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
545 * and if not ready, sent a START_STOP to start (maybe spin up) and
546 * then send the INQUIRY again, since the INQUIRY can change after
547 * a device is initialized.
548 *
549 * Ideally, start a device if explicitly asked to do so. This
550 * assumes that a device is spun up on power on, spun down on
551 * request, and then spun up on request.
552 */
553
554 /*
555 * The scanning code needs to know the scsi_level, even if no
556 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
557 * non-zero LUNs can be scanned.
558 */
559 sdev->scsi_level = inq_result[2] & 0x07;
560 if (sdev->scsi_level >= 2 ||
561 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
562 sdev->scsi_level++;
563
564 return;
565}
566
567/**
568 * scsi_add_lun - allocate and fully initialze a Scsi_Device
569 * @sdevscan: holds information to be stored in the new Scsi_Device
570 * @sdevnew: store the address of the newly allocated Scsi_Device
571 * @inq_result: holds the result of a previous INQUIRY to the LUN
572 * @bflags: black/white list flag
573 *
574 * Description:
575 * Allocate and initialize a Scsi_Device matching sdevscan. Optionally
576 * set fields based on values in *@bflags. If @sdevnew is not
577 * NULL, store the address of the new Scsi_Device in *@sdevnew (needed
578 * when scanning a particular LUN).
579 *
580 * Return:
581 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
582 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
583 **/
584static int scsi_add_lun(struct scsi_device *sdev, char *inq_result, int *bflags)
585{
586 /*
587 * XXX do not save the inquiry, since it can change underneath us,
588 * save just vendor/model/rev.
589 *
590 * Rather than save it and have an ioctl that retrieves the saved
591 * value, have an ioctl that executes the same INQUIRY code used
592 * in scsi_probe_lun, let user level programs doing INQUIRY
593 * scanning run at their own risk, or supply a user level program
594 * that can correctly scan.
595 */
596 sdev->inquiry = kmalloc(sdev->inquiry_len, GFP_ATOMIC);
597 if (sdev->inquiry == NULL) {
598 return SCSI_SCAN_NO_RESPONSE;
599 }
600
601 memcpy(sdev->inquiry, inq_result, sdev->inquiry_len);
602 sdev->vendor = (char *) (sdev->inquiry + 8);
603 sdev->model = (char *) (sdev->inquiry + 16);
604 sdev->rev = (char *) (sdev->inquiry + 32);
605
606 if (*bflags & BLIST_ISROM) {
607 /*
608 * It would be better to modify sdev->type, and set
609 * sdev->removable, but then the print_inquiry() output
610 * would not show TYPE_ROM; if print_inquiry() is removed
611 * the issue goes away.
612 */
613 inq_result[0] = TYPE_ROM;
614 inq_result[1] |= 0x80; /* removable */
615 } else if (*bflags & BLIST_NO_ULD_ATTACH)
616 sdev->no_uld_attach = 1;
617
618 switch (sdev->type = (inq_result[0] & 0x1f)) {
619 case TYPE_TAPE:
620 case TYPE_DISK:
621 case TYPE_PRINTER:
622 case TYPE_MOD:
623 case TYPE_PROCESSOR:
624 case TYPE_SCANNER:
625 case TYPE_MEDIUM_CHANGER:
626 case TYPE_ENCLOSURE:
627 case TYPE_COMM:
628 sdev->writeable = 1;
629 break;
630 case TYPE_WORM:
631 case TYPE_ROM:
632 sdev->writeable = 0;
633 break;
634 default:
635 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
636 }
637
638 print_inquiry(inq_result);
639
640 /*
641 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
642 * spec says: The device server is capable of supporting the
643 * specified peripheral device type on this logical unit. However,
644 * the physical device is not currently connected to this logical
645 * unit.
646 *
647 * The above is vague, as it implies that we could treat 001 and
648 * 011 the same. Stay compatible with previous code, and create a
649 * Scsi_Device for a PQ of 1
650 *
651 * Don't set the device offline here; rather let the upper
652 * level drivers eval the PQ to decide whether they should
653 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
654 */
655
656 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
657 sdev->removable = (0x80 & inq_result[1]) >> 7;
658 sdev->lockable = sdev->removable;
659 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
660
661 if (sdev->scsi_level >= SCSI_3 || (sdev->inquiry_len > 56 &&
662 inq_result[56] & 0x04))
663 sdev->ppr = 1;
664 if (inq_result[7] & 0x60)
665 sdev->wdtr = 1;
666 if (inq_result[7] & 0x10)
667 sdev->sdtr = 1;
668
669 sprintf(sdev->devfs_name, "scsi/host%d/bus%d/target%d/lun%d",
670 sdev->host->host_no, sdev->channel,
671 sdev->id, sdev->lun);
672
673 /*
674 * End driverfs/devfs code.
675 */
676
677 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
678 !(*bflags & BLIST_NOTQ))
679 sdev->tagged_supported = 1;
680 /*
681 * Some devices (Texel CD ROM drives) have handshaking problems
682 * when used with the Seagate controllers. borken is initialized
683 * to 1, and then set it to 0 here.
684 */
685 if ((*bflags & BLIST_BORKEN) == 0)
686 sdev->borken = 0;
687
688 /*
689 * Apparently some really broken devices (contrary to the SCSI
690 * standards) need to be selected without asserting ATN
691 */
692 if (*bflags & BLIST_SELECT_NO_ATN)
693 sdev->select_no_atn = 1;
694
695 /*
696 * Some devices may not want to have a start command automatically
697 * issued when a device is added.
698 */
699 if (*bflags & BLIST_NOSTARTONADD)
700 sdev->no_start_on_add = 1;
701
702 if (*bflags & BLIST_SINGLELUN)
703 sdev->single_lun = 1;
704
705
706 sdev->use_10_for_rw = 1;
707
708 if (*bflags & BLIST_MS_SKIP_PAGE_08)
709 sdev->skip_ms_page_8 = 1;
710
711 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
712 sdev->skip_ms_page_3f = 1;
713
714 if (*bflags & BLIST_USE_10_BYTE_MS)
715 sdev->use_10_for_ms = 1;
716
717 /* set the device running here so that slave configure
718 * may do I/O */
719 scsi_device_set_state(sdev, SDEV_RUNNING);
720
721 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
722 sdev->use_192_bytes_for_3f = 1;
723
724 if (*bflags & BLIST_NOT_LOCKABLE)
725 sdev->lockable = 0;
726
727 if (*bflags & BLIST_RETRY_HWERROR)
728 sdev->retry_hwerror = 1;
729
730 transport_configure_device(&sdev->sdev_gendev);
731
732 if (sdev->host->hostt->slave_configure)
733 sdev->host->hostt->slave_configure(sdev);
734
735 /*
736 * Ok, the device is now all set up, we can
737 * register it and tell the rest of the kernel
738 * about it.
739 */
740 scsi_sysfs_add_sdev(sdev);
741
742 return SCSI_SCAN_LUN_PRESENT;
743}
744
745/**
746 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
747 * @starget: pointer to target device structure
748 * @lun: LUN of target device
749 * @sdevscan: probe the LUN corresponding to this Scsi_Device
750 * @sdevnew: store the value of any new Scsi_Device allocated
751 * @bflagsp: store bflags here if not NULL
752 *
753 * Description:
754 * Call scsi_probe_lun, if a LUN with an attached device is found,
755 * allocate and set it up by calling scsi_add_lun.
756 *
757 * Return:
758 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
759 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
760 * attached at the LUN
761 * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
762 **/
763static int scsi_probe_and_add_lun(struct scsi_target *starget,
764 uint lun, int *bflagsp,
765 struct scsi_device **sdevp, int rescan,
766 void *hostdata)
767{
768 struct scsi_device *sdev;
769 struct scsi_request *sreq;
770 unsigned char *result;
771 int bflags, res = SCSI_SCAN_NO_RESPONSE;
772 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
773
774 /*
775 * The rescan flag is used as an optimization, the first scan of a
776 * host adapter calls into here with rescan == 0.
777 */
778 if (rescan) {
779 sdev = scsi_device_lookup_by_target(starget, lun);
780 if (sdev) {
781 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
782 "scsi scan: device exists on %s\n",
783 sdev->sdev_gendev.bus_id));
784 if (sdevp)
785 *sdevp = sdev;
786 else
787 scsi_device_put(sdev);
788
789 if (bflagsp)
790 *bflagsp = scsi_get_device_flags(sdev,
791 sdev->vendor,
792 sdev->model);
793 return SCSI_SCAN_LUN_PRESENT;
794 }
795 }
796
797 sdev = scsi_alloc_sdev(starget, lun, hostdata);
798 if (!sdev)
799 goto out;
800 sreq = scsi_allocate_request(sdev, GFP_ATOMIC);
801 if (!sreq)
802 goto out_free_sdev;
803 result = kmalloc(256, GFP_ATOMIC |
Al Virobc861202005-04-24 12:28:34 -0700804 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 if (!result)
806 goto out_free_sreq;
807
808 scsi_probe_lun(sreq, result, &bflags);
809 if (sreq->sr_result)
810 goto out_free_result;
811
812 /*
813 * result contains valid SCSI INQUIRY data.
814 */
815 if ((result[0] >> 5) == 3) {
816 /*
817 * For a Peripheral qualifier 3 (011b), the SCSI
818 * spec says: The device server is not capable of
819 * supporting a physical device on this logical
820 * unit.
821 *
822 * For disks, this implies that there is no
823 * logical disk configured at sdev->lun, but there
824 * is a target id responding.
825 */
826 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
827 "scsi scan: peripheral qualifier of 3,"
828 " no device added\n"));
829 res = SCSI_SCAN_TARGET_PRESENT;
830 goto out_free_result;
831 }
832
833 res = scsi_add_lun(sdev, result, &bflags);
834 if (res == SCSI_SCAN_LUN_PRESENT) {
835 if (bflags & BLIST_KEY) {
836 sdev->lockable = 0;
837 scsi_unlock_floptical(sreq, result);
838 }
839 if (bflagsp)
840 *bflagsp = bflags;
841 }
842
843 out_free_result:
844 kfree(result);
845 out_free_sreq:
846 scsi_release_request(sreq);
847 out_free_sdev:
848 if (res == SCSI_SCAN_LUN_PRESENT) {
849 if (sdevp) {
850 scsi_device_get(sdev);
851 *sdevp = sdev;
852 }
853 } else {
854 if (sdev->host->hostt->slave_destroy)
855 sdev->host->hostt->slave_destroy(sdev);
856 transport_destroy_device(&sdev->sdev_gendev);
857 put_device(&sdev->sdev_gendev);
858 }
859 out:
860 return res;
861}
862
863/**
864 * scsi_sequential_lun_scan - sequentially scan a SCSI target
865 * @starget: pointer to target structure to scan
866 * @bflags: black/white list flag for LUN 0
867 * @lun0_res: result of scanning LUN 0
868 *
869 * Description:
870 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
871 * scanned) to some maximum lun until a LUN is found with no device
872 * attached. Use the bflags to figure out any oddities.
873 *
874 * Modifies sdevscan->lun.
875 **/
876static void scsi_sequential_lun_scan(struct scsi_target *starget,
877 int bflags, int lun0_res, int scsi_level,
878 int rescan)
879{
880 unsigned int sparse_lun, lun, max_dev_lun;
881 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
882
883 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
884 "%s\n", starget->dev.bus_id));
885
886 max_dev_lun = min(max_scsi_luns, shost->max_lun);
887 /*
888 * If this device is known to support sparse multiple units,
889 * override the other settings, and scan all of them. Normally,
890 * SCSI-3 devices should be scanned via the REPORT LUNS.
891 */
892 if (bflags & BLIST_SPARSELUN) {
893 max_dev_lun = shost->max_lun;
894 sparse_lun = 1;
895 } else
896 sparse_lun = 0;
897
898 /*
899 * If not sparse lun and no device attached at LUN 0 do not scan
900 * any further.
901 */
902 if (!sparse_lun && (lun0_res != SCSI_SCAN_LUN_PRESENT))
903 return;
904
905 /*
906 * If less than SCSI_1_CSS, and no special lun scaning, stop
907 * scanning; this matches 2.4 behaviour, but could just be a bug
908 * (to continue scanning a SCSI_1_CSS device).
909 *
910 * This test is broken. We might not have any device on lun0 for
911 * a sparselun device, and if that's the case then how would we
912 * know the real scsi_level, eh? It might make sense to just not
913 * scan any SCSI_1 device for non-0 luns, but that check would best
914 * go into scsi_alloc_sdev() and just have it return null when asked
915 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
916 *
917 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
918 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
919 == 0))
920 return;
921 */
922 /*
923 * If this device is known to support multiple units, override
924 * the other settings, and scan all of them.
925 */
926 if (bflags & BLIST_FORCELUN)
927 max_dev_lun = shost->max_lun;
928 /*
929 * REGAL CDC-4X: avoid hang after LUN 4
930 */
931 if (bflags & BLIST_MAX5LUN)
932 max_dev_lun = min(5U, max_dev_lun);
933 /*
934 * Do not scan SCSI-2 or lower device past LUN 7, unless
935 * BLIST_LARGELUN.
936 */
937 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
938 max_dev_lun = min(8U, max_dev_lun);
939
940 /*
941 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
942 * until we reach the max, or no LUN is found and we are not
943 * sparse_lun.
944 */
945 for (lun = 1; lun < max_dev_lun; ++lun)
946 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
947 NULL) != SCSI_SCAN_LUN_PRESENT) &&
948 !sparse_lun)
949 return;
950}
951
952/**
953 * scsilun_to_int: convert a scsi_lun to an int
954 * @scsilun: struct scsi_lun to be converted.
955 *
956 * Description:
957 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
958 * integer, and return the result. The caller must check for
959 * truncation before using this function.
960 *
961 * Notes:
962 * The struct scsi_lun is assumed to be four levels, with each level
963 * effectively containing a SCSI byte-ordered (big endian) short; the
964 * addressing bits of each level are ignored (the highest two bits).
965 * For a description of the LUN format, post SCSI-3 see the SCSI
966 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
967 *
968 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
969 * the integer: 0x0b030a04
970 **/
971static int scsilun_to_int(struct scsi_lun *scsilun)
972{
973 int i;
974 unsigned int lun;
975
976 lun = 0;
977 for (i = 0; i < sizeof(lun); i += 2)
978 lun = lun | (((scsilun->scsi_lun[i] << 8) |
979 scsilun->scsi_lun[i + 1]) << (i * 8));
980 return lun;
981}
982
983/**
984 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
985 * @sdevscan: scan the host, channel, and id of this Scsi_Device
986 *
987 * Description:
988 * If @sdevscan is for a SCSI-3 or up device, send a REPORT LUN
989 * command, and scan the resulting list of LUNs by calling
990 * scsi_probe_and_add_lun.
991 *
992 * Modifies sdevscan->lun.
993 *
994 * Return:
995 * 0: scan completed (or no memory, so further scanning is futile)
996 * 1: no report lun scan, or not configured
997 **/
998static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
999 int rescan)
1000{
1001 char devname[64];
1002 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1003 unsigned int length;
1004 unsigned int lun;
1005 unsigned int num_luns;
1006 unsigned int retries;
1007 struct scsi_lun *lunp, *lun_data;
1008 struct scsi_request *sreq;
1009 u8 *data;
1010 struct scsi_sense_hdr sshdr;
1011 struct scsi_target *starget = scsi_target(sdev);
1012
1013 /*
1014 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1015 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1016 * support more than 8 LUNs.
1017 */
1018 if ((bflags & BLIST_NOREPORTLUN) ||
1019 sdev->scsi_level < SCSI_2 ||
1020 (sdev->scsi_level < SCSI_3 &&
1021 (!(bflags & BLIST_REPORTLUN2) || sdev->host->max_lun <= 8)) )
1022 return 1;
1023 if (bflags & BLIST_NOLUN)
1024 return 0;
1025
1026 sreq = scsi_allocate_request(sdev, GFP_ATOMIC);
1027 if (!sreq)
1028 goto out;
1029
1030 sprintf(devname, "host %d channel %d id %d",
1031 sdev->host->host_no, sdev->channel, sdev->id);
1032
1033 /*
1034 * Allocate enough to hold the header (the same size as one scsi_lun)
1035 * plus the max number of luns we are requesting.
1036 *
1037 * Reallocating and trying again (with the exact amount we need)
1038 * would be nice, but then we need to somehow limit the size
1039 * allocated based on the available memory and the limits of
1040 * kmalloc - we don't want a kmalloc() failure of a huge value to
1041 * prevent us from finding any LUNs on this target.
1042 */
1043 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
1044 lun_data = kmalloc(length, GFP_ATOMIC |
1045 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1046 if (!lun_data)
1047 goto out_release_request;
1048
1049 scsi_cmd[0] = REPORT_LUNS;
1050
1051 /*
1052 * bytes 1 - 5: reserved, set to zero.
1053 */
1054 memset(&scsi_cmd[1], 0, 5);
1055
1056 /*
1057 * bytes 6 - 9: length of the command.
1058 */
1059 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
1060 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
1061 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
1062 scsi_cmd[9] = (unsigned char) length & 0xff;
1063
1064 scsi_cmd[10] = 0; /* reserved */
1065 scsi_cmd[11] = 0; /* control */
1066 sreq->sr_cmd_len = 0;
1067 sreq->sr_data_direction = DMA_FROM_DEVICE;
1068
1069 /*
1070 * We can get a UNIT ATTENTION, for example a power on/reset, so
1071 * retry a few times (like sd.c does for TEST UNIT READY).
1072 * Experience shows some combinations of adapter/devices get at
1073 * least two power on/resets.
1074 *
1075 * Illegal requests (for devices that do not support REPORT LUNS)
1076 * should come through as a check condition, and will not generate
1077 * a retry.
1078 */
1079 for (retries = 0; retries < 3; retries++) {
1080 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
1081 " REPORT LUNS to %s (try %d)\n", devname,
1082 retries));
1083 scsi_wait_req(sreq, scsi_cmd, lun_data, length,
1084 SCSI_TIMEOUT + 4*HZ, 3);
1085 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
1086 " %s (try %d) result 0x%x\n", sreq->sr_result
1087 ? "failed" : "successful", retries,
1088 sreq->sr_result));
1089 if (sreq->sr_result == 0)
1090 break;
1091 else if (scsi_request_normalize_sense(sreq, &sshdr)) {
1092 if (sshdr.sense_key != UNIT_ATTENTION)
1093 break;
1094 }
1095 }
1096
1097 if (sreq->sr_result) {
1098 /*
1099 * The device probably does not support a REPORT LUN command
1100 */
1101 kfree(lun_data);
1102 scsi_release_request(sreq);
1103 return 1;
1104 }
1105 scsi_release_request(sreq);
1106
1107 /*
1108 * Get the length from the first four bytes of lun_data.
1109 */
1110 data = (u8 *) lun_data->scsi_lun;
1111 length = ((data[0] << 24) | (data[1] << 16) |
1112 (data[2] << 8) | (data[3] << 0));
1113
1114 num_luns = (length / sizeof(struct scsi_lun));
1115 if (num_luns > max_scsi_report_luns) {
1116 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1117 " of %d luns reported, try increasing"
1118 " max_scsi_report_luns.\n", devname,
1119 max_scsi_report_luns, num_luns);
1120 num_luns = max_scsi_report_luns;
1121 }
1122
1123 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUN scan of"
1124 " host %d channel %d id %d\n", sdev->host->host_no,
1125 sdev->channel, sdev->id));
1126
1127 /*
1128 * Scan the luns in lun_data. The entry at offset 0 is really
1129 * the header, so start at 1 and go up to and including num_luns.
1130 */
1131 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1132 lun = scsilun_to_int(lunp);
1133
1134 /*
1135 * Check if the unused part of lunp is non-zero, and so
1136 * does not fit in lun.
1137 */
1138 if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) {
1139 int i;
1140
1141 /*
1142 * Output an error displaying the LUN in byte order,
1143 * this differs from what linux would print for the
1144 * integer LUN value.
1145 */
1146 printk(KERN_WARNING "scsi: %s lun 0x", devname);
1147 data = (char *)lunp->scsi_lun;
1148 for (i = 0; i < sizeof(struct scsi_lun); i++)
1149 printk("%02x", data[i]);
1150 printk(" has a LUN larger than currently supported.\n");
1151 } else if (lun == 0) {
1152 /*
1153 * LUN 0 has already been scanned.
1154 */
1155 } else if (lun > sdev->host->max_lun) {
1156 printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
1157 " than allowed by the host adapter\n",
1158 devname, lun);
1159 } else {
1160 int res;
1161
1162 res = scsi_probe_and_add_lun(starget,
1163 lun, NULL, NULL, rescan, NULL);
1164 if (res == SCSI_SCAN_NO_RESPONSE) {
1165 /*
1166 * Got some results, but now none, abort.
1167 */
1168 printk(KERN_ERR "scsi: Unexpected response"
1169 " from %s lun %d while scanning, scan"
1170 " aborted\n", devname, lun);
1171 break;
1172 }
1173 }
1174 }
1175
1176 kfree(lun_data);
1177 return 0;
1178
1179 out_release_request:
1180 scsi_release_request(sreq);
1181 out:
1182 /*
1183 * We are out of memory, don't try scanning any further.
1184 */
1185 printk(ALLOC_FAILURE_MSG, __FUNCTION__);
1186 return 0;
1187}
1188
1189struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1190 uint id, uint lun, void *hostdata)
1191{
1192 struct scsi_device *sdev;
1193 struct device *parent = &shost->shost_gendev;
1194 int res;
1195 struct scsi_target *starget = scsi_alloc_target(parent, channel, id);
1196
1197 if (!starget)
1198 return ERR_PTR(-ENOMEM);
1199
1200 down(&shost->scan_mutex);
1201 res = scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1202 if (res != SCSI_SCAN_LUN_PRESENT)
1203 sdev = ERR_PTR(-ENODEV);
1204 up(&shost->scan_mutex);
1205 scsi_target_reap(starget);
1206 put_device(&starget->dev);
1207
1208 return sdev;
1209}
1210EXPORT_SYMBOL(__scsi_add_device);
1211
1212void scsi_rescan_device(struct device *dev)
1213{
1214 struct scsi_driver *drv;
1215
1216 if (!dev->driver)
1217 return;
1218
1219 drv = to_scsi_driver(dev->driver);
1220 if (try_module_get(drv->owner)) {
1221 if (drv->rescan)
1222 drv->rescan(dev);
1223 module_put(drv->owner);
1224 }
1225}
1226EXPORT_SYMBOL(scsi_rescan_device);
1227
1228/**
1229 * scsi_scan_target - scan a target id, possibly including all LUNs on the
1230 * target.
1231 * @sdevsca: Scsi_Device handle for scanning
1232 * @shost: host to scan
1233 * @channel: channel to scan
1234 * @id: target id to scan
1235 *
1236 * Description:
1237 * Scan the target id on @shost, @channel, and @id. Scan at least LUN
1238 * 0, and possibly all LUNs on the target id.
1239 *
1240 * Use the pre-allocated @sdevscan as a handle for the scanning. This
1241 * function sets sdevscan->host, sdevscan->id and sdevscan->lun; the
1242 * scanning functions modify sdevscan->lun.
1243 *
1244 * First try a REPORT LUN scan, if that does not scan the target, do a
1245 * sequential scan of LUNs on the target id.
1246 **/
1247void scsi_scan_target(struct device *parent, unsigned int channel,
1248 unsigned int id, unsigned int lun, int rescan)
1249{
1250 struct Scsi_Host *shost = dev_to_shost(parent);
1251 int bflags = 0;
1252 int res;
1253 struct scsi_device *sdev = NULL;
1254 struct scsi_target *starget;
1255
1256 if (shost->this_id == id)
1257 /*
1258 * Don't scan the host adapter
1259 */
1260 return;
1261
1262
1263 starget = scsi_alloc_target(parent, channel, id);
1264
1265 if (!starget)
1266 return;
1267
1268 get_device(&starget->dev);
1269 if (lun != SCAN_WILD_CARD) {
1270 /*
1271 * Scan for a specific host/chan/id/lun.
1272 */
1273 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1274 goto out_reap;
1275 }
1276
1277 /*
1278 * Scan LUN 0, if there is some response, scan further. Ideally, we
1279 * would not configure LUN 0 until all LUNs are scanned.
1280 */
1281 res = scsi_probe_and_add_lun(starget, 0, &bflags, &sdev, rescan, NULL);
1282 if (res == SCSI_SCAN_LUN_PRESENT) {
1283 if (scsi_report_lun_scan(sdev, bflags, rescan) != 0)
1284 /*
1285 * The REPORT LUN did not scan the target,
1286 * do a sequential scan.
1287 */
1288 scsi_sequential_lun_scan(starget, bflags,
1289 res, sdev->scsi_level, rescan);
1290 } else if (res == SCSI_SCAN_TARGET_PRESENT) {
1291 /*
1292 * There's a target here, but lun 0 is offline so we
1293 * can't use the report_lun scan. Fall back to a
1294 * sequential lun scan with a bflags of SPARSELUN and
1295 * a default scsi level of SCSI_2
1296 */
1297 scsi_sequential_lun_scan(starget, BLIST_SPARSELUN,
1298 SCSI_SCAN_TARGET_PRESENT, SCSI_2, rescan);
1299 }
1300 if (sdev)
1301 scsi_device_put(sdev);
1302
1303 out_reap:
1304 /* now determine if the target has any children at all
1305 * and if not, nuke it */
1306 scsi_target_reap(starget);
1307
1308 put_device(&starget->dev);
1309}
1310EXPORT_SYMBOL(scsi_scan_target);
1311
1312static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1313 unsigned int id, unsigned int lun, int rescan)
1314{
1315 uint order_id;
1316
1317 if (id == SCAN_WILD_CARD)
1318 for (id = 0; id < shost->max_id; ++id) {
1319 /*
1320 * XXX adapter drivers when possible (FCP, iSCSI)
1321 * could modify max_id to match the current max,
1322 * not the absolute max.
1323 *
1324 * XXX add a shost id iterator, so for example,
1325 * the FC ID can be the same as a target id
1326 * without a huge overhead of sparse id's.
1327 */
1328 if (shost->reverse_ordering)
1329 /*
1330 * Scan from high to low id.
1331 */
1332 order_id = shost->max_id - id - 1;
1333 else
1334 order_id = id;
1335 scsi_scan_target(&shost->shost_gendev, channel, order_id, lun, rescan);
1336 }
1337 else
1338 scsi_scan_target(&shost->shost_gendev, channel, id, lun, rescan);
1339}
1340
1341int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1342 unsigned int id, unsigned int lun, int rescan)
1343{
1344 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "%s: <%u:%u:%u:%u>\n",
1345 __FUNCTION__, shost->host_no, channel, id, lun));
1346
1347 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1348 ((id != SCAN_WILD_CARD) && (id > shost->max_id)) ||
1349 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1350 return -EINVAL;
1351
1352 down(&shost->scan_mutex);
1353 if (channel == SCAN_WILD_CARD)
1354 for (channel = 0; channel <= shost->max_channel; channel++)
1355 scsi_scan_channel(shost, channel, id, lun, rescan);
1356 else
1357 scsi_scan_channel(shost, channel, id, lun, rescan);
1358 up(&shost->scan_mutex);
1359
1360 return 0;
1361}
1362
1363/**
1364 * scsi_scan_host - scan the given adapter
1365 * @shost: adapter to scan
1366 **/
1367void scsi_scan_host(struct Scsi_Host *shost)
1368{
1369 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1370 SCAN_WILD_CARD, 0);
1371}
1372EXPORT_SYMBOL(scsi_scan_host);
1373
1374/**
1375 * scsi_scan_single_target - scan the given SCSI target
1376 * @shost: adapter to scan
1377 * @chan: channel to scan
1378 * @id: target id to scan
1379 **/
1380void scsi_scan_single_target(struct Scsi_Host *shost,
1381 unsigned int chan, unsigned int id)
1382{
1383 scsi_scan_host_selected(shost, chan, id, SCAN_WILD_CARD, 1);
1384}
1385EXPORT_SYMBOL(scsi_scan_single_target);
1386
1387void scsi_forget_host(struct Scsi_Host *shost)
1388{
1389 struct scsi_target *starget, *tmp;
1390 unsigned long flags;
1391
1392 /*
1393 * Ok, this look a bit strange. We always look for the first device
1394 * on the list as scsi_remove_device removes them from it - thus we
1395 * also have to release the lock.
1396 * We don't need to get another reference to the device before
1397 * releasing the lock as we already own the reference from
1398 * scsi_register_device that's release in scsi_remove_device. And
1399 * after that we don't look at sdev anymore.
1400 */
1401 spin_lock_irqsave(shost->host_lock, flags);
1402 list_for_each_entry_safe(starget, tmp, &shost->__targets, siblings) {
1403 spin_unlock_irqrestore(shost->host_lock, flags);
1404 scsi_remove_target(&starget->dev);
1405 spin_lock_irqsave(shost->host_lock, flags);
1406 }
1407 spin_unlock_irqrestore(shost->host_lock, flags);
1408}
1409
1410/*
1411 * Function: scsi_get_host_dev()
1412 *
1413 * Purpose: Create a Scsi_Device that points to the host adapter itself.
1414 *
1415 * Arguments: SHpnt - Host that needs a Scsi_Device
1416 *
1417 * Lock status: None assumed.
1418 *
1419 * Returns: The Scsi_Device or NULL
1420 *
1421 * Notes:
1422 * Attach a single Scsi_Device to the Scsi_Host - this should
1423 * be made to look like a "pseudo-device" that points to the
1424 * HA itself.
1425 *
1426 * Note - this device is not accessible from any high-level
1427 * drivers (including generics), which is probably not
1428 * optimal. We can add hooks later to attach
1429 */
1430struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1431{
1432 struct scsi_device *sdev;
1433 struct scsi_target *starget;
1434
1435 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1436 if (!starget)
1437 return NULL;
1438
1439 sdev = scsi_alloc_sdev(starget, 0, NULL);
1440 if (sdev) {
1441 sdev->sdev_gendev.parent = get_device(&starget->dev);
1442 sdev->borken = 0;
1443 }
1444 put_device(&starget->dev);
1445 return sdev;
1446}
1447EXPORT_SYMBOL(scsi_get_host_dev);
1448
1449/*
1450 * Function: scsi_free_host_dev()
1451 *
1452 * Purpose: Free a scsi_device that points to the host adapter itself.
1453 *
1454 * Arguments: SHpnt - Host that needs a Scsi_Device
1455 *
1456 * Lock status: None assumed.
1457 *
1458 * Returns: Nothing
1459 *
1460 * Notes:
1461 */
1462void scsi_free_host_dev(struct scsi_device *sdev)
1463{
1464 BUG_ON(sdev->id != sdev->host->this_id);
1465
1466 if (sdev->host->hostt->slave_destroy)
1467 sdev->host->hostt->slave_destroy(sdev);
1468 transport_destroy_device(&sdev->sdev_gendev);
1469 put_device(&sdev->sdev_gendev);
1470}
1471EXPORT_SYMBOL(scsi_free_host_dev);
1472