Line data Source code
1 : /*
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/module.h>
29 : #include <linux/moduleparam.h>
30 : #include <linux/init.h>
31 : #include <linux/blkdev.h>
32 : #include <linux/delay.h>
33 : #include <linux/kthread.h>
34 : #include <linux/spinlock.h>
35 : #include <linux/async.h>
36 :
37 : #include <scsi/scsi.h>
38 : #include <scsi/scsi_cmnd.h>
39 : #include <scsi/scsi_device.h>
40 : #include <scsi/scsi_driver.h>
41 : #include <scsi/scsi_devinfo.h>
42 : #include <scsi/scsi_host.h>
43 : #include <scsi/scsi_transport.h>
44 : #include <scsi/scsi_eh.h>
45 :
46 : #include "scsi_priv.h"
47 : #include "scsi_logging.h"
48 :
49 : #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
50 : " SCSI scanning, some SCSI devices might not be configured\n"
51 :
52 : /*
53 : * Default timeout
54 : */
55 : #define SCSI_TIMEOUT (2*HZ)
56 :
57 : /*
58 : * Prefix values for the SCSI id's (stored in sysfs name field)
59 : */
60 : #define SCSI_UID_SER_NUM 'S'
61 : #define SCSI_UID_UNKNOWN 'Z'
62 :
63 : /*
64 : * Return values of some of the scanning functions.
65 : *
66 : * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
67 : * includes allocation or general failures preventing IO from being sent.
68 : *
69 : * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
70 : * on the given LUN.
71 : *
72 : * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
73 : * given LUN.
74 : */
75 : #define SCSI_SCAN_NO_RESPONSE 0
76 : #define SCSI_SCAN_TARGET_PRESENT 1
77 : #define SCSI_SCAN_LUN_PRESENT 2
78 :
79 1 : static const char *scsi_null_device_strs = "nullnullnullnull";
80 :
81 : #define MAX_SCSI_LUNS 512
82 :
83 : #ifdef CONFIG_SCSI_MULTI_LUN
84 1 : static unsigned int max_scsi_luns = MAX_SCSI_LUNS;
85 : #else
86 : static unsigned int max_scsi_luns = 1;
87 : #endif
88 :
89 : module_param_named(max_luns, max_scsi_luns, uint, S_IRUGO|S_IWUSR);
90 : MODULE_PARM_DESC(max_luns,
91 : "last scsi LUN (should be between 1 and 2^32-1)");
92 :
93 : #ifdef CONFIG_SCSI_SCAN_ASYNC
94 : #define SCSI_SCAN_TYPE_DEFAULT "async"
95 : #else
96 : #define SCSI_SCAN_TYPE_DEFAULT "sync"
97 : #endif
98 :
99 1 : static char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT;
100 :
101 : module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
102 : MODULE_PARM_DESC(scan, "sync, async or none");
103 :
104 : /*
105 : * max_scsi_report_luns: the maximum number of LUNS that will be
106 : * returned from the REPORT LUNS command. 8 times this value must
107 : * be allocated. In theory this could be up to an 8 byte value, but
108 : * in practice, the maximum number of LUNs suppored by any device
109 : * is about 16k.
110 : */
111 1 : static unsigned int max_scsi_report_luns = 511;
112 :
113 : module_param_named(max_report_luns, max_scsi_report_luns, uint, S_IRUGO|S_IWUSR);
114 : MODULE_PARM_DESC(max_report_luns,
115 : "REPORT LUNS maximum number of LUNS received (should be"
116 : " between 1 and 16384)");
117 :
118 1 : static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
119 :
120 : module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
121 : MODULE_PARM_DESC(inq_timeout,
122 : "Timeout (in seconds) waiting for devices to answer INQUIRY."
123 : " Default is 20. Some devices may need more; most need less.");
124 :
125 : /* This lock protects only this list */
126 1 : static DEFINE_SPINLOCK(async_scan_lock);
127 1 : static LIST_HEAD(scanning_hosts);
128 1 :
129 : struct async_scan_data {
130 : struct list_head list;
131 : struct Scsi_Host *shost;
132 : struct completion prev_finished;
133 : };
134 :
135 : /**
136 : * scsi_complete_async_scans - Wait for asynchronous scans to complete
137 : *
138 : * When this function returns, any host which started scanning before
139 : * this function was called will have finished its scan. Hosts which
140 : * started scanning after this function was called may or may not have
141 : * finished.
142 : */
143 : int scsi_complete_async_scans(void)
144 : {
145 3 : struct async_scan_data *data;
146 3 :
147 3 : do {
148 15 : if (list_empty(&scanning_hosts))
149 6 : return 0;
150 3 : /* If we can't get memory immediately, that's OK. Just
151 3 : * sleep a little. Even if we never get memory, the async
152 : * scans will finish eventually.
153 : */
154 12 : data = kmalloc(sizeof(*data), GFP_KERNEL);
155 6 : if (!data)
156 3 : msleep(1);
157 6 : } while (!data);
158 :
159 6 : data->shost = NULL;
160 6 : init_completion(&data->prev_finished);
161 :
162 6 : spin_lock(&async_scan_lock);
163 : /* Check that there's still somebody else on the list */
164 12 : if (list_empty(&scanning_hosts))
165 3 : goto done;
166 6 : list_add_tail(&data->list, &scanning_hosts);
167 6 : spin_unlock(&async_scan_lock);
168 :
169 3 : printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
170 3 : wait_for_completion(&data->prev_finished);
171 :
172 6 : spin_lock(&async_scan_lock);
173 6 : list_del(&data->list);
174 12 : if (!list_empty(&scanning_hosts)) {
175 6 : struct async_scan_data *next = list_entry(scanning_hosts.next,
176 : struct async_scan_data, list);
177 3 : complete(&next->prev_finished);
178 : }
179 : done:
180 12 : spin_unlock(&async_scan_lock);
181 :
182 6 : kfree(data);
183 3 : return 0;
184 : }
185 :
186 : /* Only exported for the benefit of scsi_wait_scan */
187 : EXPORT_SYMBOL_GPL(scsi_complete_async_scans);
188 :
189 : #ifndef MODULE
190 : /*
191 : * For async scanning we need to wait for all the scans to complete before
192 : * trying to mount the root fs. Otherwise non-modular drivers may not be ready
193 : * yet.
194 : */
195 : late_initcall(scsi_complete_async_scans);
196 : #endif
197 :
198 : /**
199 : * scsi_unlock_floptical - unlock device via a special MODE SENSE command
200 : * @sdev: scsi device to send command to
201 : * @result: area to store the result of the MODE SENSE
202 : *
203 : * Description:
204 : * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
205 : * Called for BLIST_KEY devices.
206 : **/
207 : static void scsi_unlock_floptical(struct scsi_device *sdev,
208 : unsigned char *result)
209 32 : {
210 : unsigned char scsi_cmd[MAX_COMMAND_SIZE];
211 :
212 32 : printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
213 32 : scsi_cmd[0] = MODE_SENSE;
214 32 : scsi_cmd[1] = 0;
215 32 : scsi_cmd[2] = 0x2e;
216 32 : scsi_cmd[3] = 0;
217 32 : scsi_cmd[4] = 0x2a; /* size */
218 32 : scsi_cmd[5] = 0;
219 128 : scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
220 32 : SCSI_TIMEOUT, 3, NULL);
221 : }
222 :
223 : /**
224 : * scsi_alloc_sdev - allocate and setup a scsi_Device
225 : * @starget: which target to allocate a &scsi_device for
226 : * @lun: which lun
227 : * @hostdata: usually NULL and set by ->slave_alloc instead
228 : *
229 : * Description:
230 : * Allocate, initialize for io, and return a pointer to a scsi_Device.
231 : * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
232 : * adds scsi_Device to the appropriate list.
233 : *
234 : * Return value:
235 : * scsi_Device pointer, or NULL on failure.
236 : **/
237 : static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
238 : unsigned int lun, void *hostdata)
239 : {
240 40 : struct scsi_device *sdev;
241 80 : int display_failure_msg = 1, ret;
242 160 : struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
243 40 : extern void scsi_evt_thread(struct work_struct *work);
244 40 :
245 200 : sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
246 40 : GFP_ATOMIC);
247 120 : if (!sdev)
248 40 : goto out;
249 :
250 40 : sdev->vendor = scsi_null_device_strs;
251 40 : sdev->model = scsi_null_device_strs;
252 40 : sdev->rev = scsi_null_device_strs;
253 40 : sdev->host = shost;
254 40 : sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
255 40 : sdev->id = starget->id;
256 40 : sdev->lun = lun;
257 40 : sdev->channel = starget->channel;
258 40 : sdev->sdev_state = SDEV_CREATED;
259 80 : INIT_LIST_HEAD(&sdev->siblings);
260 80 : INIT_LIST_HEAD(&sdev->same_target_siblings);
261 80 : INIT_LIST_HEAD(&sdev->cmd_list);
262 80 : INIT_LIST_HEAD(&sdev->starved_entry);
263 80 : INIT_LIST_HEAD(&sdev->event_list);
264 160 : spin_lock_init(&sdev->list_lock);
265 280 : INIT_WORK(&sdev->event_work, scsi_evt_thread);
266 :
267 40 : sdev->sdev_gendev.parent = get_device(&starget->dev);
268 40 : sdev->sdev_target = starget;
269 :
270 : /* usually NULL and set by ->slave_alloc instead */
271 40 : sdev->hostdata = hostdata;
272 :
273 : /* if the device needs this changing, it may do so in the
274 : * slave_configure function */
275 40 : sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
276 :
277 : /*
278 : * Some low level driver could use device->type
279 : */
280 40 : sdev->type = -1;
281 :
282 : /*
283 : * Assume that the device will have handshaking problems,
284 : * and then fix this field later if it turns out it
285 : * doesn't
286 : */
287 40 : sdev->borken = 1;
288 :
289 80 : sdev->request_queue = scsi_alloc_queue(sdev);
290 120 : if (!sdev->request_queue) {
291 : /* release fn is set up in scsi_sysfs_device_initialise, so
292 : * have to free and put manually here */
293 40 : put_device(&starget->dev);
294 40 : kfree(sdev);
295 40 : goto out;
296 : }
297 40 : blk_get_queue(sdev->request_queue);
298 40 : sdev->request_queue->queuedata = sdev;
299 160 : scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
300 :
301 80 : scsi_sysfs_device_initialize(sdev);
302 :
303 120 : if (shost->hostt->slave_alloc) {
304 120 : ret = shost->hostt->slave_alloc(sdev);
305 80 : if (ret) {
306 : /*
307 : * if LLDD reports slave not present, don't clutter
308 : * console with alloc failure messages
309 : */
310 80 : if (ret == -ENXIO)
311 40 : display_failure_msg = 0;
312 40 : goto out_device_destroy;
313 : }
314 : }
315 :
316 40 : return sdev;
317 40 :
318 : out_device_destroy:
319 80 : scsi_device_set_state(sdev, SDEV_DEL);
320 40 : transport_destroy_device(&sdev->sdev_gendev);
321 40 : put_device(&sdev->sdev_dev);
322 40 : put_device(&sdev->sdev_gendev);
323 : out:
324 280 : if (display_failure_msg)
325 120 : printk(ALLOC_FAILURE_MSG, __func__);
326 120 : return NULL;
327 : }
328 :
329 : static void scsi_target_destroy(struct scsi_target *starget)
330 : {
331 336 : struct device *dev = &starget->dev;
332 672 : struct Scsi_Host *shost = dev_to_shost(dev->parent);
333 168 : unsigned long flags;
334 168 :
335 336 : transport_destroy_device(dev);
336 504 : spin_lock_irqsave(shost->host_lock, flags);
337 504 : if (shost->hostt->target_destroy)
338 168 : shost->hostt->target_destroy(starget);
339 336 : list_del_init(&starget->siblings);
340 336 : spin_unlock_irqrestore(shost->host_lock, flags);
341 168 : put_device(dev);
342 168 : }
343 :
344 : static void scsi_target_dev_release(struct device *dev)
345 : {
346 2 : struct device *parent = dev->parent;
347 3 : struct scsi_target *starget = to_scsi_target(dev);
348 1 :
349 1 : kfree(starget);
350 1 : put_device(parent);
351 1 : }
352 :
353 1 : static struct device_type scsi_target_type = {
354 : .name = "scsi_target",
355 : .release = scsi_target_dev_release,
356 : };
357 :
358 : int scsi_is_target_device(const struct device *dev)
359 : {
360 0 : return dev->type == &scsi_target_type;
361 : }
362 : EXPORT_SYMBOL(scsi_is_target_device);
363 :
364 : static struct scsi_target *__scsi_find_target(struct device *parent,
365 : int channel, uint id)
366 : {
367 16 : struct scsi_target *starget, *found_starget = NULL;
368 32 : struct Scsi_Host *shost = dev_to_shost(parent);
369 8 : /*
370 8 : * Search for an existing target for this sdev.
371 8 : */
372 72 : list_for_each_entry(starget, &shost->__targets, siblings) {
373 48 : if (starget->id == id &&
374 8 : starget->channel == channel) {
375 8 : found_starget = starget;
376 8 : break;
377 : }
378 8 : }
379 16 : if (found_starget)
380 8 : get_device(&found_starget->dev);
381 :
382 8 : return found_starget;
383 : }
384 :
385 : /**
386 : * scsi_alloc_target - allocate a new or find an existing target
387 : * @parent: parent of the target (need not be a scsi host)
388 : * @channel: target channel number (zero if no channels)
389 : * @id: target id number
390 : *
391 : * Return an existing target if one exists, provided it hasn't already
392 : * gone into STARGET_DEL state, otherwise allocate a new target.
393 : *
394 : * The target is returned with an incremented reference, so the caller
395 : * is responsible for both reaping and doing a last put
396 : */
397 : static struct scsi_target *scsi_alloc_target(struct device *parent,
398 : int channel, uint id)
399 : {
400 32 : struct Scsi_Host *shost = dev_to_shost(parent);
401 16 : struct device *dev = NULL;
402 8 : unsigned long flags;
403 24 : const int size = sizeof(struct scsi_target)
404 8 : + shost->transportt->target_size;
405 8 : struct scsi_target *starget;
406 8 : struct scsi_target *found_target;
407 8 : int error;
408 8 :
409 32 : starget = kzalloc(size, GFP_KERNEL);
410 24 : if (!starget) {
411 16 : printk(KERN_ERR "%s: allocation failure\n", __func__);
412 8 : return NULL;
413 : }
414 8 : dev = &starget->dev;
415 8 : device_initialize(dev);
416 8 : starget->reap_ref = 1;
417 8 : dev->parent = get_device(parent);
418 8 : dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
419 : #ifndef CONFIG_SYSFS_DEPRECATED
420 8 : dev->bus = &scsi_bus_type;
421 : #endif
422 8 : dev->type = &scsi_target_type;
423 8 : starget->id = id;
424 8 : starget->channel = channel;
425 8 : starget->can_queue = 0;
426 16 : INIT_LIST_HEAD(&starget->siblings);
427 16 : INIT_LIST_HEAD(&starget->devices);
428 8 : starget->state = STARGET_CREATED;
429 8 : starget->scsi_level = SCSI_2;
430 8 : starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
431 : retry:
432 32 : spin_lock_irqsave(shost->host_lock, flags);
433 :
434 16 : found_target = __scsi_find_target(parent, channel, id);
435 16 : if (found_target)
436 8 : goto found;
437 :
438 16 : list_add_tail(&starget->siblings, &shost->__targets);
439 16 : spin_unlock_irqrestore(shost->host_lock, flags);
440 : /* allocate and add */
441 8 : transport_setup_device(dev);
442 24 : if (shost->hostt->target_alloc) {
443 24 : error = shost->hostt->target_alloc(starget);
444 :
445 16 : if(error) {
446 32 : dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
447 : /* don't want scsi_target_reap to do the final
448 : * put because it will be under the host lock */
449 16 : scsi_target_destroy(starget);
450 8 : return NULL;
451 : }
452 : }
453 8 : get_device(dev);
454 :
455 8 : return starget;
456 8 :
457 : found:
458 8 : found_target->reap_ref++;
459 16 : spin_unlock_irqrestore(shost->host_lock, flags);
460 24 : if (found_target->state != STARGET_DEL) {
461 8 : put_device(parent);
462 8 : kfree(starget);
463 8 : return found_target;
464 : }
465 : /* Unfortunately, we found a dying target; need to
466 : * wait until it's dead before we can get a new one */
467 8 : put_device(&found_target->dev);
468 8 : flush_scheduled_work();
469 8 : goto retry;
470 : }
471 :
472 : static void scsi_target_reap_usercontext(struct work_struct *work)
473 : {
474 0 : struct scsi_target *starget =
475 0 : container_of(work, struct scsi_target, ew.work);
476 :
477 0 : transport_remove_device(&starget->dev);
478 0 : device_del(&starget->dev);
479 0 : scsi_target_destroy(starget);
480 0 : }
481 :
482 : /**
483 : * scsi_target_reap - check to see if target is in use and destroy if not
484 : * @starget: target to be checked
485 : *
486 : * This is used after removing a LUN or doing a last put of the target
487 : * it checks atomically that nothing is using the target and removes
488 : * it if so.
489 : */
490 : void scsi_target_reap(struct scsi_target *starget)
491 : {
492 640 : struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
493 160 : unsigned long flags;
494 160 : enum scsi_target_state state;
495 160 : int empty;
496 160 :
497 640 : spin_lock_irqsave(shost->host_lock, flags);
498 320 : state = starget->state;
499 2080 : empty = --starget->reap_ref == 0 &&
500 160 : list_empty(&starget->devices) ? 1 : 0;
501 640 : spin_unlock_irqrestore(shost->host_lock, flags);
502 :
503 320 : if (!empty)
504 160 : return;
505 :
506 960 : BUG_ON(state == STARGET_DEL);
507 160 : starget->state = STARGET_DEL;
508 320 : if (state == STARGET_CREATED)
509 320 : scsi_target_destroy(starget);
510 : else
511 160 : execute_in_process_context(scsi_target_reap_usercontext,
512 : &starget->ew);
513 320 : }
514 :
515 : /**
516 : * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string
517 : * @s: INQUIRY result string to sanitize
518 : * @len: length of the string
519 : *
520 : * Description:
521 : * The SCSI spec says that INQUIRY vendor, product, and revision
522 : * strings must consist entirely of graphic ASCII characters,
523 : * padded on the right with spaces. Since not all devices obey
524 : * this rule, we will replace non-graphic or non-ASCII characters
525 : * with spaces. Exception: a NUL character is interpreted as a
526 : * string terminator, so all the following characters are set to
527 : * spaces.
528 : **/
529 : static void sanitize_inquiry_string(unsigned char *s, int len)
530 : {
531 320 : int terminated = 0;
532 :
533 800 : for (; len > 0; (--len, ++s)) {
534 640 : if (*s == 0)
535 320 : terminated = 1;
536 960 : if (terminated || *s < 0x20 || *s > 0x7e)
537 160 : *s = ' ';
538 : }
539 : }
540 160 :
541 : /**
542 : * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
543 : * @sdev: scsi_device to probe
544 : * @inq_result: area to store the INQUIRY result
545 : * @result_len: len of inq_result
546 : * @bflags: store any bflags found here
547 : *
548 : * Description:
549 : * Probe the lun associated with @req using a standard SCSI INQUIRY;
550 : *
551 : * If the INQUIRY is successful, zero is returned and the
552 : * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
553 : * are copied to the scsi_device any flags value is stored in *@bflags.
554 : **/
555 : static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
556 : int result_len, int *bflags)
557 : {
558 32 : unsigned char scsi_cmd[MAX_COMMAND_SIZE];
559 32 : int first_inquiry_len, try_inquiry_len, next_inquiry_len;
560 64 : int response_len = 0;
561 32 : int pass, count, result;
562 32 : struct scsi_sense_hdr sshdr;
563 32 :
564 64 : *bflags = 0;
565 32 :
566 32 : /* Perform up to 3 passes. The first pass uses a conservative
567 32 : * transfer length of 36 unless sdev->inquiry_len specifies a
568 32 : * different value. */
569 288 : first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
570 64 : try_inquiry_len = first_inquiry_len;
571 32 : pass = 1;
572 32 :
573 : next_pass:
574 : SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
575 : "scsi scan: INQUIRY pass %d length %d\n",
576 : pass, try_inquiry_len));
577 :
578 : /* Each pass gets up to three chances to ignore Unit Attention */
579 192 : for (count = 0; count < 3; ++count) {
580 96 : int resid;
581 32 :
582 32 : memset(scsi_cmd, 0, 6);
583 32 : scsi_cmd[0] = INQUIRY;
584 32 : scsi_cmd[4] = (unsigned char) try_inquiry_len;
585 32 :
586 32 : memset(inq_result, 0, try_inquiry_len);
587 :
588 128 : result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
589 : inq_result, try_inquiry_len, &sshdr,
590 : HZ / 2 + HZ * scsi_inq_timeout, 3,
591 : &resid);
592 :
593 : SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s "
594 : "with code 0x%x\n",
595 : result ? "failed" : "successful", result));
596 :
597 64 : if (result) {
598 : /*
599 : * not-ready to ready transition [asc/ascq=0x28/0x0]
600 : * or power-on, reset [asc/ascq=0x29/0x0], continue.
601 : * INQUIRY should not yield UNIT_ATTENTION
602 : * but many buggy devices do so anyway.
603 : */
604 192 : if ((driver_byte(result) & DRIVER_SENSE) &&
605 : scsi_sense_valid(&sshdr)) {
606 192 : if ((sshdr.sense_key == UNIT_ATTENTION) &&
607 : ((sshdr.asc == 0x28) ||
608 : (sshdr.asc == 0x29)) &&
609 : (sshdr.ascq == 0))
610 32 : continue;
611 : }
612 : } else {
613 : /*
614 : * if nothing was transferred, we try
615 : * again. It's a workaround for some USB
616 : * devices.
617 : */
618 64 : if (resid == try_inquiry_len)
619 32 : continue;
620 : }
621 64 : break;
622 64 : }
623 :
624 192 : if (result == 0) {
625 192 : sanitize_inquiry_string(&inq_result[8], 8);
626 64 : sanitize_inquiry_string(&inq_result[16], 16);
627 64 : sanitize_inquiry_string(&inq_result[32], 4);
628 :
629 32 : response_len = inq_result[4] + 5;
630 64 : if (response_len > 255)
631 32 : response_len = first_inquiry_len; /* sanity */
632 :
633 : /*
634 : * Get any flags for this device.
635 : *
636 : * XXX add a bflags to scsi_device, and replace the
637 : * corresponding bit fields in scsi_device, so bflags
638 : * need not be passed as an argument.
639 : */
640 64 : *bflags = scsi_get_device_flags(sdev, &inq_result[8],
641 : &inq_result[16]);
642 :
643 : /* When the first pass succeeds we gain information about
644 : * what larger transfer lengths might work. */
645 64 : if (pass == 1) {
646 64 : if (BLIST_INQUIRY_36 & *bflags)
647 32 : next_inquiry_len = 36;
648 64 : else if (BLIST_INQUIRY_58 & *bflags)
649 32 : next_inquiry_len = 58;
650 96 : else if (sdev->inquiry_len)
651 64 : next_inquiry_len = sdev->inquiry_len;
652 : else
653 32 : next_inquiry_len = response_len;
654 :
655 : /* If more data is available perform the second pass */
656 64 : if (next_inquiry_len > try_inquiry_len) {
657 32 : try_inquiry_len = next_inquiry_len;
658 32 : pass = 2;
659 32 : goto next_pass;
660 : }
661 : }
662 :
663 192 : } else if (pass == 2) {
664 96 : printk(KERN_INFO "scsi scan: %d byte inquiry failed. "
665 : "Consider BLIST_INQUIRY_36 for this device\n",
666 : try_inquiry_len);
667 :
668 : /* If this pass failed, the third pass goes back and transfers
669 : * the same amount as we successfully got in the first pass. */
670 96 : try_inquiry_len = first_inquiry_len;
671 96 : pass = 3;
672 96 : goto next_pass;
673 : }
674 :
675 : /* If the last transfer attempt got an error, assume the
676 : * peripheral doesn't exist or is dead. */
677 256 : if (result)
678 128 : return -EIO;
679 :
680 : /* Don't report any more data than the device says is valid */
681 1024 : sdev->inquiry_len = min(try_inquiry_len, response_len);
682 :
683 : /*
684 : * XXX Abort if the response length is less than 36? If less than
685 : * 32, the lookup of the device flags (above) could be invalid,
686 : * and it would be possible to take an incorrect action - we do
687 : * not want to hang because of a short INQUIRY. On the flip side,
688 : * if the device is spun down or becoming ready (and so it gives a
689 : * short INQUIRY), an abort here prevents any further use of the
690 : * device, including spin up.
691 : *
692 : * On the whole, the best approach seems to be to assume the first
693 : * 36 bytes are valid no matter what the device says. That's
694 : * better than copying < 36 bytes to the inquiry-result buffer
695 : * and displaying garbage for the Vendor, Product, or Revision
696 : * strings.
697 : */
698 384 : if (sdev->inquiry_len < 36) {
699 256 : printk(KERN_INFO "scsi scan: INQUIRY result too short (%d),"
700 : " using 36\n", sdev->inquiry_len);
701 128 : sdev->inquiry_len = 36;
702 : }
703 :
704 : /*
705 : * Related to the above issue:
706 : *
707 : * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
708 : * and if not ready, sent a START_STOP to start (maybe spin up) and
709 : * then send the INQUIRY again, since the INQUIRY can change after
710 : * a device is initialized.
711 : *
712 : * Ideally, start a device if explicitly asked to do so. This
713 : * assumes that a device is spun up on power on, spun down on
714 : * request, and then spun up on request.
715 : */
716 :
717 : /*
718 : * The scanning code needs to know the scsi_level, even if no
719 : * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
720 : * non-zero LUNs can be scanned.
721 : */
722 128 : sdev->scsi_level = inq_result[2] & 0x07;
723 1024 : if (sdev->scsi_level >= 2 ||
724 : (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
725 256 : sdev->scsi_level++;
726 128 : sdev->sdev_target->scsi_level = sdev->scsi_level;
727 :
728 128 : return 0;
729 : }
730 :
731 : /**
732 : * scsi_add_lun - allocate and fully initialze a scsi_device
733 : * @sdev: holds information to be stored in the new scsi_device
734 : * @inq_result: holds the result of a previous INQUIRY to the LUN
735 : * @bflags: black/white list flag
736 : * @async: 1 if this device is being scanned asynchronously
737 : *
738 : * Description:
739 : * Initialize the scsi_device @sdev. Optionally set fields based
740 : * on values in *@bflags.
741 : *
742 : * Return:
743 : * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
744 : * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
745 : **/
746 : static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
747 : int *bflags, int async)
748 : {
749 64 : int ret;
750 64 :
751 64 : /*
752 64 : * XXX do not save the inquiry, since it can change underneath us,
753 64 : * save just vendor/model/rev.
754 64 : *
755 64 : * Rather than save it and have an ioctl that retrieves the saved
756 64 : * value, have an ioctl that executes the same INQUIRY code used
757 64 : * in scsi_probe_lun, let user level programs doing INQUIRY
758 64 : * scanning run at their own risk, or supply a user level program
759 64 : * that can correctly scan.
760 64 : */
761 64 :
762 64 : /*
763 : * Copy at least 36 bytes of INQUIRY data, so that we don't
764 : * dereference unallocated memory when accessing the Vendor,
765 : * Product, and Revision strings. Badly behaved devices may set
766 : * the INQUIRY Additional Length byte to a small value, indicating
767 : * these strings are invalid, but often they contain plausible data
768 : * nonetheless. It doesn't matter if the device sent < 36 bytes
769 : * total, since scsi_probe_lun() initializes inq_result with 0s.
770 : */
771 : sdev->inquiry = kmemdup(inq_result,
772 640 : max_t(size_t, sdev->inquiry_len, 36),
773 : GFP_ATOMIC);
774 192 : if (sdev->inquiry == NULL)
775 64 : return SCSI_SCAN_NO_RESPONSE;
776 :
777 64 : sdev->vendor = (char *) (sdev->inquiry + 8);
778 64 : sdev->model = (char *) (sdev->inquiry + 16);
779 64 : sdev->rev = (char *) (sdev->inquiry + 32);
780 :
781 128 : if (*bflags & BLIST_ISROM) {
782 64 : sdev->type = TYPE_ROM;
783 64 : sdev->removable = 1;
784 : } else {
785 64 : sdev->type = (inq_result[0] & 0x1f);
786 64 : sdev->removable = (inq_result[1] & 0x80) >> 7;
787 : }
788 :
789 : switch (sdev->type) {
790 256 : case TYPE_RBC:
791 256 : case TYPE_TAPE:
792 256 : case TYPE_DISK:
793 256 : case TYPE_PRINTER:
794 256 : case TYPE_MOD:
795 256 : case TYPE_PROCESSOR:
796 256 : case TYPE_SCANNER:
797 256 : case TYPE_MEDIUM_CHANGER:
798 256 : case TYPE_ENCLOSURE:
799 256 : case TYPE_COMM:
800 256 : case TYPE_RAID:
801 256 : case TYPE_OSD:
802 64 : sdev->writeable = 1;
803 64 : break;
804 320 : case TYPE_ROM:
805 320 : case TYPE_WORM:
806 64 : sdev->writeable = 0;
807 64 : break;
808 128 : default:
809 192 : printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
810 64 : }
811 128 :
812 448 : if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
813 128 : /* RBC and MMC devices can return SCSI-3 compliance and yet
814 64 : * still not support REPORT LUNS, so make them act as
815 64 : * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
816 64 : * specifically set */
817 192 : if ((*bflags & BLIST_REPORTLUN2) == 0)
818 128 : *bflags |= BLIST_NOREPORTLUN;
819 64 : }
820 64 :
821 : /*
822 : * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
823 : * spec says: The device server is capable of supporting the
824 : * specified peripheral device type on this logical unit. However,
825 : * the physical device is not currently connected to this logical
826 : * unit.
827 : *
828 : * The above is vague, as it implies that we could treat 001 and
829 : * 011 the same. Stay compatible with previous code, and create a
830 : * scsi_device for a PQ of 1
831 : *
832 : * Don't set the device offline here; rather let the upper
833 : * level drivers eval the PQ to decide whether they should
834 : * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
835 : */
836 :
837 64 : sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
838 64 : sdev->lockable = sdev->removable;
839 384 : sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
840 :
841 512 : if (sdev->scsi_level >= SCSI_3 ||
842 : (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
843 64 : sdev->ppr = 1;
844 128 : if (inq_result[7] & 0x60)
845 64 : sdev->wdtr = 1;
846 128 : if (inq_result[7] & 0x10)
847 64 : sdev->sdtr = 1;
848 :
849 576 : sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
850 : "ANSI: %d%s\n", scsi_device_type(sdev->type),
851 256 : sdev->vendor, sdev->model, sdev->rev,
852 : sdev->inq_periph_qual, inq_result[2] & 0x07,
853 : (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
854 :
855 448 : if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
856 : !(*bflags & BLIST_NOTQ))
857 64 : sdev->tagged_supported = 1;
858 :
859 : /*
860 : * Some devices (Texel CD ROM drives) have handshaking problems
861 : * when used with the Seagate controllers. borken is initialized
862 : * to 1, and then set it to 0 here.
863 : */
864 128 : if ((*bflags & BLIST_BORKEN) == 0)
865 64 : sdev->borken = 0;
866 :
867 128 : if (*bflags & BLIST_NO_ULD_ATTACH)
868 64 : sdev->no_uld_attach = 1;
869 :
870 : /*
871 : * Apparently some really broken devices (contrary to the SCSI
872 : * standards) need to be selected without asserting ATN
873 : */
874 128 : if (*bflags & BLIST_SELECT_NO_ATN)
875 64 : sdev->select_no_atn = 1;
876 :
877 : /*
878 : * Maximum 512 sector transfer length
879 : * broken RA4x00 Compaq Disk Array
880 : */
881 128 : if (*bflags & BLIST_MAX_512)
882 64 : blk_queue_max_sectors(sdev->request_queue, 512);
883 :
884 : /*
885 : * Some devices may not want to have a start command automatically
886 : * issued when a device is added.
887 : */
888 128 : if (*bflags & BLIST_NOSTARTONADD)
889 64 : sdev->no_start_on_add = 1;
890 :
891 128 : if (*bflags & BLIST_SINGLELUN)
892 192 : scsi_target(sdev)->single_lun = 1;
893 :
894 128 : sdev->use_10_for_rw = 1;
895 :
896 256 : if (*bflags & BLIST_MS_SKIP_PAGE_08)
897 128 : sdev->skip_ms_page_8 = 1;
898 :
899 256 : if (*bflags & BLIST_MS_SKIP_PAGE_3F)
900 128 : sdev->skip_ms_page_3f = 1;
901 :
902 256 : if (*bflags & BLIST_USE_10_BYTE_MS)
903 128 : sdev->use_10_for_ms = 1;
904 :
905 : /* set the device running here so that slave configure
906 : * may do I/O */
907 256 : ret = scsi_device_set_state(sdev, SDEV_RUNNING);
908 128 : if (ret) {
909 128 : ret = scsi_device_set_state(sdev, SDEV_BLOCK);
910 :
911 128 : if (ret) {
912 384 : sdev_printk(KERN_ERR, sdev,
913 : "in wrong state %s to complete scan\n",
914 : scsi_device_state_name(sdev->sdev_state));
915 64 : return SCSI_SCAN_NO_RESPONSE;
916 : }
917 : }
918 :
919 256 : if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
920 128 : sdev->use_192_bytes_for_3f = 1;
921 :
922 256 : if (*bflags & BLIST_NOT_LOCKABLE)
923 128 : sdev->lockable = 0;
924 :
925 256 : if (*bflags & BLIST_RETRY_HWERROR)
926 128 : sdev->retry_hwerror = 1;
927 :
928 128 : transport_configure_device(&sdev->sdev_gendev);
929 :
930 384 : if (sdev->host->hostt->slave_configure) {
931 384 : ret = sdev->host->hostt->slave_configure(sdev);
932 256 : if (ret) {
933 : /*
934 : * if LLDD reports slave not present, don't clutter
935 : * console with alloc failure messages
936 : */
937 256 : if (ret != -ENXIO) {
938 384 : sdev_printk(KERN_ERR, sdev,
939 : "failed to configure device\n");
940 : }
941 192 : return SCSI_SCAN_NO_RESPONSE;
942 : }
943 : }
944 :
945 128 : sdev->max_queue_depth = sdev->queue_depth;
946 :
947 : /*
948 : * Ok, the device is now all set up, we can
949 : * register it and tell the rest of the kernel
950 : * about it.
951 : */
952 1024 : if (!async && scsi_sysfs_add_sdev(sdev) != 0)
953 64 : return SCSI_SCAN_NO_RESPONSE;
954 :
955 192 : return SCSI_SCAN_LUN_PRESENT;
956 : }
957 :
958 : #ifdef CONFIG_SCSI_LOGGING
959 : /**
960 : * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
961 : * @buf: Output buffer with at least end-first+1 bytes of space
962 : * @inq: Inquiry buffer (input)
963 : * @first: Offset of string into inq
964 : * @end: Index after last character in inq
965 : */
966 : static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
967 : unsigned first, unsigned end)
968 : {
969 : unsigned term = 0, idx;
970 :
971 : for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
972 : if (inq[idx+first] > ' ') {
973 : buf[idx] = inq[idx+first];
974 : term = idx+1;
975 : } else {
976 : buf[idx] = ' ';
977 : }
978 : }
979 : buf[term] = 0;
980 : return buf;
981 : }
982 : #endif
983 :
984 : /**
985 : * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
986 : * @starget: pointer to target device structure
987 : * @lun: LUN of target device
988 : * @bflagsp: store bflags here if not NULL
989 : * @sdevp: probe the LUN corresponding to this scsi_device
990 : * @rescan: if nonzero skip some code only needed on first scan
991 : * @hostdata: passed to scsi_alloc_sdev()
992 : *
993 : * Description:
994 : * Call scsi_probe_lun, if a LUN with an attached device is found,
995 : * allocate and set it up by calling scsi_add_lun.
996 : *
997 : * Return:
998 : * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
999 : * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1000 : * attached at the LUN
1001 : * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1002 : **/
1003 : static int scsi_probe_and_add_lun(struct scsi_target *starget,
1004 : uint lun, int *bflagsp,
1005 : struct scsi_device **sdevp, int rescan,
1006 32 : void *hostdata)
1007 32 : {
1008 32 : struct scsi_device *sdev;
1009 32 : unsigned char *result;
1010 96 : int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1011 128 : struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1012 32 :
1013 32 : /*
1014 32 : * The rescan flag is used as an optimization, the first scan of a
1015 32 : * host adapter calls into here with rescan == 0.
1016 32 : */
1017 96 : sdev = scsi_device_lookup_by_target(starget, lun);
1018 64 : if (sdev) {
1019 224 : if (rescan || !scsi_device_created(sdev)) {
1020 32 : SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1021 : "scsi scan: device exists on %s\n",
1022 : dev_name(&sdev->sdev_gendev)));
1023 128 : if (sdevp)
1024 64 : *sdevp = sdev;
1025 : else
1026 128 : scsi_device_put(sdev);
1027 :
1028 192 : if (bflagsp)
1029 384 : *bflagsp = scsi_get_device_flags(sdev,
1030 : sdev->vendor,
1031 : sdev->model);
1032 128 : return SCSI_SCAN_LUN_PRESENT;
1033 : }
1034 64 : scsi_device_put(sdev);
1035 : } else
1036 160 : sdev = scsi_alloc_sdev(starget, lun, hostdata);
1037 128 : if (!sdev)
1038 64 : goto out;
1039 :
1040 480 : result = kmalloc(result_len, GFP_ATOMIC |
1041 : ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
1042 64 : if (!result)
1043 32 : goto out_free_sdev;
1044 :
1045 224 : if (scsi_probe_lun(sdev, result, result_len, &bflags))
1046 32 : goto out_free_result;
1047 :
1048 64 : if (bflagsp)
1049 32 : *bflagsp = bflags;
1050 : /*
1051 : * result contains valid SCSI INQUIRY data.
1052 : */
1053 128 : if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
1054 : /*
1055 : * For a Peripheral qualifier 3 (011b), the SCSI
1056 : * spec says: The device server is not capable of
1057 : * supporting a physical device on this logical
1058 : * unit.
1059 : *
1060 : * For disks, this implies that there is no
1061 : * logical disk configured at sdev->lun, but there
1062 : * is a target id responding.
1063 : */
1064 : SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1065 : " peripheral qualifier of 3, device not"
1066 : " added\n"))
1067 : if (lun == 0) {
1068 : SCSI_LOG_SCAN_BUS(1, {
1069 : unsigned char vend[9];
1070 : unsigned char mod[17];
1071 :
1072 : sdev_printk(KERN_INFO, sdev,
1073 : "scsi scan: consider passing scsi_mod."
1074 : "dev_flags=%s:%s:0x240 or 0x1000240\n",
1075 : scsi_inq_str(vend, result, 8, 16),
1076 : scsi_inq_str(mod, result, 16, 32));
1077 : });
1078 :
1079 : }
1080 :
1081 32 : res = SCSI_SCAN_TARGET_PRESENT;
1082 32 : goto out_free_result;
1083 : }
1084 :
1085 : /*
1086 : * Some targets may set slight variations of PQ and PDT to signal
1087 : * that no LUN is present, so don't add sdev in these cases.
1088 : * Two specific examples are:
1089 : * 1) NetApp targets: return PQ=1, PDT=0x1f
1090 : * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1091 : * in the UFI 1.0 spec (we cannot rely on reserved bits).
1092 : *
1093 : * References:
1094 : * 1) SCSI SPC-3, pp. 145-146
1095 : * PQ=1: "A peripheral device having the specified peripheral
1096 : * device type is not connected to this logical unit. However, the
1097 : * device server is capable of supporting the specified peripheral
1098 : * device type on this logical unit."
1099 : * PDT=0x1f: "Unknown or no device type"
1100 : * 2) USB UFI 1.0, p. 20
1101 : * PDT=00h Direct-access device (floppy)
1102 : * PDT=1Fh none (no FDD connected to the requested logical unit)
1103 : */
1104 320 : if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1105 : (result[0] & 0x1f) == 0x1f &&
1106 : !scsi_is_wlun(lun)) {
1107 : SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1108 : "scsi scan: peripheral device type"
1109 : " of 31, no device added\n"));
1110 32 : res = SCSI_SCAN_TARGET_PRESENT;
1111 32 : goto out_free_result;
1112 : }
1113 :
1114 512 : res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1115 64 : if (res == SCSI_SCAN_LUN_PRESENT) {
1116 64 : if (bflags & BLIST_KEY) {
1117 32 : sdev->lockable = 0;
1118 64 : scsi_unlock_floptical(sdev, result);
1119 : }
1120 : }
1121 :
1122 : out_free_result:
1123 128 : kfree(result);
1124 : out_free_sdev:
1125 448 : if (res == SCSI_SCAN_LUN_PRESENT) {
1126 384 : if (sdevp) {
1127 544 : if (scsi_device_get(sdev) == 0) {
1128 32 : *sdevp = sdev;
1129 : } else {
1130 96 : __scsi_remove_device(sdev);
1131 32 : res = SCSI_SCAN_NO_RESPONSE;
1132 : }
1133 : }
1134 : } else
1135 480 : __scsi_remove_device(sdev);
1136 : out:
1137 320 : return res;
1138 256 : }
1139 :
1140 : /**
1141 : * scsi_sequential_lun_scan - sequentially scan a SCSI target
1142 : * @starget: pointer to target structure to scan
1143 : * @bflags: black/white list flag for LUN 0
1144 : * @scsi_level: Which version of the standard does this device adhere to
1145 : * @rescan: passed to scsi_probe_add_lun()
1146 : *
1147 : * Description:
1148 : * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1149 : * scanned) to some maximum lun until a LUN is found with no device
1150 : * attached. Use the bflags to figure out any oddities.
1151 : *
1152 : * Modifies sdevscan->lun.
1153 : **/
1154 : static void scsi_sequential_lun_scan(struct scsi_target *starget,
1155 : int bflags, int scsi_level, int rescan)
1156 : {
1157 8 : unsigned int sparse_lun, lun, max_dev_lun;
1158 32 : struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1159 8 :
1160 8 : SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
1161 8 : "%s\n", dev_name(&starget->dev)));
1162 8 :
1163 72 : max_dev_lun = min(max_scsi_luns, shost->max_lun);
1164 8 : /*
1165 8 : * If this device is known to support sparse multiple units,
1166 8 : * override the other settings, and scan all of them. Normally,
1167 8 : * SCSI-3 devices should be scanned via the REPORT LUNS.
1168 8 : */
1169 16 : if (bflags & BLIST_SPARSELUN) {
1170 8 : max_dev_lun = shost->max_lun;
1171 8 : sparse_lun = 1;
1172 : } else
1173 8 : sparse_lun = 0;
1174 :
1175 : /*
1176 : * If less than SCSI_1_CSS, and no special lun scaning, stop
1177 : * scanning; this matches 2.4 behaviour, but could just be a bug
1178 : * (to continue scanning a SCSI_1_CSS device).
1179 : *
1180 : * This test is broken. We might not have any device on lun0 for
1181 : * a sparselun device, and if that's the case then how would we
1182 : * know the real scsi_level, eh? It might make sense to just not
1183 : * scan any SCSI_1 device for non-0 luns, but that check would best
1184 : * go into scsi_alloc_sdev() and just have it return null when asked
1185 : * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1186 : *
1187 : if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1188 : ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1189 : == 0))
1190 : return;
1191 : */
1192 : /*
1193 : * If this device is known to support multiple units, override
1194 : * the other settings, and scan all of them.
1195 : */
1196 16 : if (bflags & BLIST_FORCELUN)
1197 8 : max_dev_lun = shost->max_lun;
1198 : /*
1199 : * REGAL CDC-4X: avoid hang after LUN 4
1200 : */
1201 16 : if (bflags & BLIST_MAX5LUN)
1202 64 : max_dev_lun = min(5U, max_dev_lun);
1203 : /*
1204 : * Do not scan SCSI-2 or lower device past LUN 7, unless
1205 : * BLIST_LARGELUN.
1206 : */
1207 32 : if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1208 64 : max_dev_lun = min(8U, max_dev_lun);
1209 :
1210 : /*
1211 : * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1212 : * until we reach the max, or no LUN is found and we are not
1213 : * sparse_lun.
1214 : */
1215 40 : for (lun = 1; lun < max_dev_lun; ++lun)
1216 168 : if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1217 8 : NULL) != SCSI_SCAN_LUN_PRESENT) &&
1218 : !sparse_lun)
1219 8 : return;
1220 : }
1221 :
1222 8 : /**
1223 : * scsilun_to_int: convert a scsi_lun to an int
1224 : * @scsilun: struct scsi_lun to be converted.
1225 : *
1226 : * Description:
1227 : * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
1228 : * integer, and return the result. The caller must check for
1229 : * truncation before using this function.
1230 : *
1231 : * Notes:
1232 : * The struct scsi_lun is assumed to be four levels, with each level
1233 : * effectively containing a SCSI byte-ordered (big endian) short; the
1234 : * addressing bits of each level are ignored (the highest two bits).
1235 : * For a description of the LUN format, post SCSI-3 see the SCSI
1236 : * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
1237 : *
1238 : * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
1239 : * the integer: 0x0b030a04
1240 : **/
1241 : int scsilun_to_int(struct scsi_lun *scsilun)
1242 : {
1243 8 : int i;
1244 8 : unsigned int lun;
1245 :
1246 8 : lun = 0;
1247 40 : for (i = 0; i < sizeof(lun); i += 2)
1248 24 : lun = lun | (((scsilun->scsi_lun[i] << 8) |
1249 8 : scsilun->scsi_lun[i + 1]) << (i * 8));
1250 8 : return lun;
1251 : }
1252 : EXPORT_SYMBOL(scsilun_to_int);
1253 :
1254 : /**
1255 : * int_to_scsilun: reverts an int into a scsi_lun
1256 : * @lun: integer to be reverted
1257 : * @scsilun: struct scsi_lun to be set.
1258 : *
1259 : * Description:
1260 : * Reverts the functionality of the scsilun_to_int, which packed
1261 : * an 8-byte lun value into an int. This routine unpacks the int
1262 : * back into the lun value.
1263 : * Note: the scsilun_to_int() routine does not truly handle all
1264 : * 8bytes of the lun value. This functions restores only as much
1265 : * as was set by the routine.
1266 : *
1267 : * Notes:
1268 : * Given an integer : 0x0b030a04, this function returns a
1269 : * scsi_lun of : struct scsi_lun of: 0a 04 0b 03 00 00 00 00
1270 : *
1271 : **/
1272 : void int_to_scsilun(unsigned int lun, struct scsi_lun *scsilun)
1273 : {
1274 0 : int i;
1275 :
1276 0 : memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
1277 :
1278 0 : for (i = 0; i < sizeof(lun); i += 2) {
1279 0 : scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
1280 0 : scsilun->scsi_lun[i+1] = lun & 0xFF;
1281 0 : lun = lun >> 16;
1282 : }
1283 : }
1284 : EXPORT_SYMBOL(int_to_scsilun);
1285 0 :
1286 : /**
1287 : * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1288 : * @starget: which target
1289 : * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1290 : * @rescan: nonzero if we can skip code only needed on first scan
1291 : *
1292 : * Description:
1293 : * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1294 : * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1295 : *
1296 : * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1297 : * LUNs even if it's older than SCSI-3.
1298 : * If BLIST_NOREPORTLUN is set, return 1 always.
1299 : * If BLIST_NOLUN is set, return 0 always.
1300 : *
1301 : * Return:
1302 : * 0: scan completed (or no memory, so further scanning is futile)
1303 : * 1: could not scan with REPORT LUN
1304 : **/
1305 : static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1306 : int rescan)
1307 8 : {
1308 8 : char devname[64];
1309 8 : unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1310 8 : unsigned int length;
1311 8 : unsigned int lun;
1312 8 : unsigned int num_luns;
1313 8 : unsigned int retries;
1314 8 : int result;
1315 8 : struct scsi_lun *lunp, *lun_data;
1316 8 : u8 *data;
1317 8 : struct scsi_sense_hdr sshdr;
1318 8 : struct scsi_device *sdev;
1319 32 : struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1320 16 : int ret = 0;
1321 8 :
1322 8 : /*
1323 8 : * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1324 8 : * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1325 8 : * support more than 8 LUNs.
1326 8 : */
1327 24 : if (bflags & BLIST_NOREPORTLUN)
1328 16 : return 1;
1329 56 : if (starget->scsi_level < SCSI_2 &&
1330 8 : starget->scsi_level != SCSI_UNKNOWN)
1331 16 : return 1;
1332 56 : if (starget->scsi_level < SCSI_3 &&
1333 : (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1334 8 : return 1;
1335 16 : if (bflags & BLIST_NOLUN)
1336 8 : return 0;
1337 :
1338 32 : if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1339 40 : sdev = scsi_alloc_sdev(starget, 0, NULL);
1340 16 : if (!sdev)
1341 8 : return 0;
1342 40 : if (scsi_device_get(sdev)) {
1343 24 : __scsi_remove_device(sdev);
1344 8 : return 0;
1345 : }
1346 : }
1347 :
1348 16 : sprintf(devname, "host %d channel %d id %d",
1349 : shost->host_no, sdev->channel, sdev->id);
1350 :
1351 : /*
1352 : * Allocate enough to hold the header (the same size as one scsi_lun)
1353 : * plus the max number of luns we are requesting.
1354 : *
1355 : * Reallocating and trying again (with the exact amount we need)
1356 : * would be nice, but then we need to somehow limit the size
1357 : * allocated based on the available memory and the limits of
1358 : * kmalloc - we don't want a kmalloc() failure of a huge value to
1359 : * prevent us from finding any LUNs on this target.
1360 : */
1361 16 : length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
1362 136 : lun_data = kmalloc(length, GFP_ATOMIC |
1363 : (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1364 16 : if (!lun_data) {
1365 8 : printk(ALLOC_FAILURE_MSG, __func__);
1366 8 : goto out;
1367 : }
1368 :
1369 8 : scsi_cmd[0] = REPORT_LUNS;
1370 :
1371 : /*
1372 : * bytes 1 - 5: reserved, set to zero.
1373 : */
1374 8 : memset(&scsi_cmd[1], 0, 5);
1375 :
1376 : /*
1377 : * bytes 6 - 9: length of the command.
1378 : */
1379 8 : scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
1380 8 : scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
1381 8 : scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
1382 8 : scsi_cmd[9] = (unsigned char) length & 0xff;
1383 :
1384 8 : scsi_cmd[10] = 0; /* reserved */
1385 8 : scsi_cmd[11] = 0; /* control */
1386 :
1387 : /*
1388 : * We can get a UNIT ATTENTION, for example a power on/reset, so
1389 : * retry a few times (like sd.c does for TEST UNIT READY).
1390 : * Experience shows some combinations of adapter/devices get at
1391 : * least two power on/resets.
1392 : *
1393 : * Illegal requests (for devices that do not support REPORT LUNS)
1394 : * should come through as a check condition, and will not generate
1395 : * a retry.
1396 : */
1397 40 : for (retries = 0; retries < 3; retries++) {
1398 16 : SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
1399 8 : " REPORT LUNS to %s (try %d)\n", devname,
1400 : retries));
1401 :
1402 32 : result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1403 8 : lun_data, length, &sshdr,
1404 : SCSI_TIMEOUT + 4 * HZ, 3, NULL);
1405 :
1406 : SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
1407 : " %s (try %d) result 0x%x\n", result
1408 : ? "failed" : "successful", retries, result));
1409 16 : if (result == 0)
1410 8 : break;
1411 32 : else if (scsi_sense_valid(&sshdr)) {
1412 16 : if (sshdr.sense_key != UNIT_ATTENTION)
1413 8 : break;
1414 : }
1415 : }
1416 :
1417 48 : if (result) {
1418 : /*
1419 : * The device probably does not support a REPORT LUN command
1420 : */
1421 24 : ret = 1;
1422 24 : goto out_err;
1423 : }
1424 :
1425 : /*
1426 : * Get the length from the first four bytes of lun_data.
1427 : */
1428 24 : data = (u8 *) lun_data->scsi_lun;
1429 24 : length = ((data[0] << 24) | (data[1] << 16) |
1430 : (data[2] << 8) | (data[3] << 0));
1431 :
1432 24 : num_luns = (length / sizeof(struct scsi_lun));
1433 48 : if (num_luns > max_scsi_report_luns) {
1434 24 : printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1435 : " of %d luns reported, try increasing"
1436 : " max_scsi_report_luns.\n", devname,
1437 : max_scsi_report_luns, num_luns);
1438 24 : num_luns = max_scsi_report_luns;
1439 : }
1440 :
1441 : SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1442 : "scsi scan: REPORT LUN scan\n"));
1443 :
1444 : /*
1445 : * Scan the luns in lun_data. The entry at offset 0 is really
1446 : * the header, so start at 1 and go up to and including num_luns.
1447 : */
1448 88 : for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1449 56 : lun = scsilun_to_int(lunp);
1450 8 :
1451 : /*
1452 : * Check if the unused part of lunp is non-zero, and so
1453 : * does not fit in lun.
1454 8 : */
1455 40 : if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) {
1456 : int i;
1457 :
1458 : /*
1459 : * Output an error displaying the LUN in byte order,
1460 : * this differs from what linux would print for the
1461 : * integer LUN value.
1462 : */
1463 8 : printk(KERN_WARNING "scsi: %s lun 0x", devname);
1464 8 : data = (char *)lunp->scsi_lun;
1465 40 : for (i = 0; i < sizeof(struct scsi_lun); i++)
1466 16 : printk("%02x", data[i]);
1467 24 : printk(" has a LUN larger than currently supported.\n");
1468 16 : } else if (lun > sdev->host->max_lun) {
1469 8 : printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
1470 : " than allowed by the host adapter\n",
1471 : devname, lun);
1472 : } else {
1473 : int res;
1474 :
1475 120 : res = scsi_probe_and_add_lun(starget,
1476 : lun, NULL, NULL, rescan, NULL);
1477 16 : if (res == SCSI_SCAN_NO_RESPONSE) {
1478 : /*
1479 : * Got some results, but now none, abort.
1480 : */
1481 32 : sdev_printk(KERN_ERR, sdev,
1482 : "Unexpected response"
1483 : " from lun %d while scanning, scan"
1484 : " aborted\n", lun);
1485 8 : break;
1486 : }
1487 : }
1488 : }
1489 :
1490 : out_err:
1491 40 : kfree(lun_data);
1492 : out:
1493 136 : scsi_device_put(sdev);
1494 32 : if (scsi_device_created(sdev))
1495 : /*
1496 : * the sdev we used didn't appear in the report luns scan
1497 : */
1498 24 : __scsi_remove_device(sdev);
1499 16 : return ret;
1500 : }
1501 :
1502 : struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1503 : uint id, uint lun, void *hostdata)
1504 : {
1505 0 : struct scsi_device *sdev = ERR_PTR(-ENODEV);
1506 0 : struct device *parent = &shost->shost_gendev;
1507 0 : struct scsi_target *starget;
1508 0 :
1509 0 : if (strncmp(scsi_scan_type, "none", 4) == 0)
1510 0 : return ERR_PTR(-ENODEV);
1511 0 :
1512 0 : starget = scsi_alloc_target(parent, channel, id);
1513 0 : if (!starget)
1514 0 : return ERR_PTR(-ENOMEM);
1515 :
1516 0 : mutex_lock(&shost->scan_mutex);
1517 0 : if (!shost->async_scan)
1518 0 : scsi_complete_async_scans();
1519 :
1520 0 : if (scsi_host_scan_allowed(shost))
1521 0 : scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1522 0 : mutex_unlock(&shost->scan_mutex);
1523 0 : scsi_target_reap(starget);
1524 0 : put_device(&starget->dev);
1525 :
1526 0 : return sdev;
1527 : }
1528 : EXPORT_SYMBOL(__scsi_add_device);
1529 :
1530 : int scsi_add_device(struct Scsi_Host *host, uint channel,
1531 : uint target, uint lun)
1532 0 : {
1533 0 : struct scsi_device *sdev =
1534 0 : __scsi_add_device(host, channel, target, lun, NULL);
1535 0 : if (IS_ERR(sdev))
1536 0 : return PTR_ERR(sdev);
1537 :
1538 0 : scsi_device_put(sdev);
1539 0 : return 0;
1540 : }
1541 : EXPORT_SYMBOL(scsi_add_device);
1542 :
1543 : void scsi_rescan_device(struct device *dev)
1544 : {
1545 1 : struct scsi_driver *drv;
1546 1 :
1547 4 : if (!dev->driver)
1548 1 : return;
1549 :
1550 3 : drv = to_scsi_driver(dev->driver);
1551 4 : if (try_module_get(drv->owner)) {
1552 3 : if (drv->rescan)
1553 7 : drv->rescan(dev);
1554 2 : module_put(drv->owner);
1555 : }
1556 2 : }
1557 : EXPORT_SYMBOL(scsi_rescan_device);
1558 :
1559 : static void __scsi_scan_target(struct device *parent, unsigned int channel,
1560 : unsigned int id, unsigned int lun, int rescan)
1561 : {
1562 32 : struct Scsi_Host *shost = dev_to_shost(parent);
1563 16 : int bflags = 0;
1564 8 : int res;
1565 8 : struct scsi_target *starget;
1566 8 :
1567 32 : if (shost->this_id == id)
1568 : /*
1569 : * Don't scan the host adapter
1570 : */
1571 8 : return;
1572 :
1573 40 : starget = scsi_alloc_target(parent, channel, id);
1574 16 : if (!starget)
1575 8 : return;
1576 :
1577 16 : if (lun != SCAN_WILD_CARD) {
1578 : /*
1579 : * Scan for a specific host/chan/id/lun.
1580 : */
1581 120 : scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1582 8 : goto out_reap;
1583 : }
1584 :
1585 : /*
1586 : * Scan LUN 0, if there is some response, scan further. Ideally, we
1587 : * would not configure LUN 0 until all LUNs are scanned.
1588 : */
1589 120 : res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1590 16 : if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1591 64 : if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1592 : /*
1593 : * The REPORT LUN did not scan the target,
1594 : * do a sequential scan.
1595 : */
1596 32 : scsi_sequential_lun_scan(starget, bflags,
1597 : starget->scsi_level, rescan);
1598 : }
1599 :
1600 : out_reap:
1601 : /* now determine if the target has any children at all
1602 : * and if not, nuke it */
1603 128 : scsi_target_reap(starget);
1604 24 :
1605 8 : put_device(&starget->dev);
1606 8 : }
1607 :
1608 : /**
1609 : * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1610 : * @parent: host to scan
1611 : * @channel: channel to scan
1612 : * @id: target id to scan
1613 : * @lun: Specific LUN to scan or SCAN_WILD_CARD
1614 : * @rescan: passed to LUN scanning routines
1615 : *
1616 : * Description:
1617 : * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1618 : * and possibly all LUNs on the target id.
1619 : *
1620 : * First try a REPORT LUN scan, if that does not scan the target, do a
1621 : * sequential scan of LUNs on the target id.
1622 : **/
1623 : void scsi_scan_target(struct device *parent, unsigned int channel,
1624 : unsigned int id, unsigned int lun, int rescan)
1625 : {
1626 0 : struct Scsi_Host *shost = dev_to_shost(parent);
1627 0 :
1628 0 : if (strncmp(scsi_scan_type, "none", 4) == 0)
1629 0 : return;
1630 :
1631 0 : mutex_lock(&shost->scan_mutex);
1632 0 : if (!shost->async_scan)
1633 0 : scsi_complete_async_scans();
1634 :
1635 0 : if (scsi_host_scan_allowed(shost))
1636 0 : __scsi_scan_target(parent, channel, id, lun, rescan);
1637 0 : mutex_unlock(&shost->scan_mutex);
1638 0 : }
1639 : EXPORT_SYMBOL(scsi_scan_target);
1640 :
1641 : static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1642 : unsigned int id, unsigned int lun, int rescan)
1643 : {
1644 4 : uint order_id;
1645 :
1646 8 : if (id == SCAN_WILD_CARD)
1647 20 : for (id = 0; id < shost->max_id; ++id) {
1648 4 : /*
1649 8 : * XXX adapter drivers when possible (FCP, iSCSI)
1650 : * could modify max_id to match the current max,
1651 : * not the absolute max.
1652 : *
1653 : * XXX add a shost id iterator, so for example,
1654 : * the FC ID can be the same as a target id
1655 : * without a huge overhead of sparse id's.
1656 : */
1657 8 : if (shost->reverse_ordering)
1658 : /*
1659 : * Scan from high to low id.
1660 : */
1661 4 : order_id = shost->max_id - id - 1;
1662 : else
1663 4 : order_id = id;
1664 16 : __scsi_scan_target(&shost->shost_gendev, channel,
1665 : order_id, lun, rescan);
1666 : }
1667 : else
1668 16 : __scsi_scan_target(&shost->shost_gendev, channel,
1669 8 : id, lun, rescan);
1670 : }
1671 :
1672 : int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1673 : unsigned int id, unsigned int lun, int rescan)
1674 : {
1675 2 : SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1676 : "%s: <%u:%u:%u>\n",
1677 : __func__, channel, id, lun));
1678 :
1679 24 : if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1680 : ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1681 : ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1682 2 : return -EINVAL;
1683 :
1684 2 : mutex_lock(&shost->scan_mutex);
1685 4 : if (!shost->async_scan)
1686 6 : scsi_complete_async_scans();
1687 :
1688 12 : if (scsi_host_scan_allowed(shost)) {
1689 4 : if (channel == SCAN_WILD_CARD)
1690 8 : for (channel = 0; channel <= shost->max_channel;
1691 4 : channel++)
1692 8 : scsi_scan_channel(shost, channel, id, lun,
1693 2 : rescan);
1694 : else
1695 6 : scsi_scan_channel(shost, channel, id, lun, rescan);
1696 : }
1697 6 : mutex_unlock(&shost->scan_mutex);
1698 :
1699 6 : return 0;
1700 : }
1701 :
1702 : static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1703 : {
1704 0 : struct scsi_device *sdev;
1705 0 : shost_for_each_device(sdev, shost) {
1706 0 : if (!scsi_host_scan_allowed(shost) ||
1707 0 : scsi_sysfs_add_sdev(sdev) != 0)
1708 0 : __scsi_remove_device(sdev);
1709 : }
1710 : }
1711 :
1712 0 : /**
1713 : * scsi_prep_async_scan - prepare for an async scan
1714 : * @shost: the host which will be scanned
1715 : * Returns: a cookie to be passed to scsi_finish_async_scan()
1716 : *
1717 : * Tells the midlayer this host is going to do an asynchronous scan.
1718 : * It reserves the host's position in the scanning list and ensures
1719 : * that other asynchronous scans started after this one won't affect the
1720 : * ordering of the discovered devices.
1721 : */
1722 : static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1723 : {
1724 0 : struct async_scan_data *data;
1725 0 : unsigned long flags;
1726 0 :
1727 0 : if (strncmp(scsi_scan_type, "sync", 4) == 0)
1728 0 : return NULL;
1729 0 :
1730 0 : if (shost->async_scan) {
1731 0 : printk("%s called twice for host %d", __func__,
1732 : shost->host_no);
1733 0 : dump_stack();
1734 0 : return NULL;
1735 : }
1736 :
1737 0 : data = kmalloc(sizeof(*data), GFP_KERNEL);
1738 0 : if (!data)
1739 0 : goto err;
1740 0 : data->shost = scsi_host_get(shost);
1741 0 : if (!data->shost)
1742 0 : goto err;
1743 0 : init_completion(&data->prev_finished);
1744 :
1745 0 : mutex_lock(&shost->scan_mutex);
1746 0 : spin_lock_irqsave(shost->host_lock, flags);
1747 0 : shost->async_scan = 1;
1748 0 : spin_unlock_irqrestore(shost->host_lock, flags);
1749 0 : mutex_unlock(&shost->scan_mutex);
1750 :
1751 0 : spin_lock(&async_scan_lock);
1752 0 : if (list_empty(&scanning_hosts))
1753 0 : complete(&data->prev_finished);
1754 0 : list_add_tail(&data->list, &scanning_hosts);
1755 0 : spin_unlock(&async_scan_lock);
1756 :
1757 0 : return data;
1758 0 :
1759 : err:
1760 0 : kfree(data);
1761 0 : return NULL;
1762 : }
1763 :
1764 : /**
1765 : * scsi_finish_async_scan - asynchronous scan has finished
1766 : * @data: cookie returned from earlier call to scsi_prep_async_scan()
1767 : *
1768 : * All the devices currently attached to this host have been found.
1769 : * This function announces all the devices it has found to the rest
1770 : * of the system.
1771 : */
1772 : static void scsi_finish_async_scan(struct async_scan_data *data)
1773 : {
1774 0 : struct Scsi_Host *shost;
1775 0 : unsigned long flags;
1776 0 :
1777 0 : if (!data)
1778 0 : return;
1779 0 :
1780 0 : shost = data->shost;
1781 :
1782 0 : mutex_lock(&shost->scan_mutex);
1783 :
1784 0 : if (!shost->async_scan) {
1785 0 : printk("%s called twice for host %d", __func__,
1786 : shost->host_no);
1787 0 : dump_stack();
1788 0 : mutex_unlock(&shost->scan_mutex);
1789 0 : return;
1790 : }
1791 :
1792 0 : wait_for_completion(&data->prev_finished);
1793 :
1794 0 : scsi_sysfs_add_devices(shost);
1795 :
1796 0 : spin_lock_irqsave(shost->host_lock, flags);
1797 0 : shost->async_scan = 0;
1798 0 : spin_unlock_irqrestore(shost->host_lock, flags);
1799 :
1800 0 : mutex_unlock(&shost->scan_mutex);
1801 :
1802 0 : spin_lock(&async_scan_lock);
1803 0 : list_del(&data->list);
1804 0 : if (!list_empty(&scanning_hosts)) {
1805 0 : struct async_scan_data *next = list_entry(scanning_hosts.next,
1806 : struct async_scan_data, list);
1807 0 : complete(&next->prev_finished);
1808 : }
1809 0 : spin_unlock(&async_scan_lock);
1810 :
1811 0 : scsi_host_put(shost);
1812 0 : kfree(data);
1813 0 : }
1814 :
1815 : static void do_scsi_scan_host(struct Scsi_Host *shost)
1816 : {
1817 0 : if (shost->hostt->scan_finished) {
1818 0 : unsigned long start = jiffies;
1819 0 : if (shost->hostt->scan_start)
1820 0 : shost->hostt->scan_start(shost);
1821 :
1822 0 : while (!shost->hostt->scan_finished(shost, jiffies - start))
1823 0 : msleep(10);
1824 0 : } else {
1825 0 : scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1826 0 : SCAN_WILD_CARD, 0);
1827 : }
1828 : }
1829 :
1830 : static int do_scan_async(void *_data)
1831 : {
1832 0 : struct async_scan_data *data = _data;
1833 0 : do_scsi_scan_host(data->shost);
1834 0 : scsi_finish_async_scan(data);
1835 0 : return 0;
1836 : }
1837 :
1838 : /**
1839 : * scsi_scan_host - scan the given adapter
1840 : * @shost: adapter to scan
1841 : **/
1842 : void scsi_scan_host(struct Scsi_Host *shost)
1843 : {
1844 0 : struct task_struct *p;
1845 0 : struct async_scan_data *data;
1846 0 :
1847 0 : if (strncmp(scsi_scan_type, "none", 4) == 0)
1848 0 : return;
1849 0 :
1850 0 : data = scsi_prep_async_scan(shost);
1851 0 : if (!data) {
1852 0 : do_scsi_scan_host(shost);
1853 0 : return;
1854 : }
1855 :
1856 0 : p = kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no);
1857 0 : if (IS_ERR(p))
1858 0 : do_scan_async(data);
1859 0 : }
1860 : EXPORT_SYMBOL(scsi_scan_host);
1861 :
1862 : void scsi_forget_host(struct Scsi_Host *shost)
1863 : {
1864 0 : struct scsi_device *sdev;
1865 0 : unsigned long flags;
1866 0 :
1867 0 : restart:
1868 0 : spin_lock_irqsave(shost->host_lock, flags);
1869 0 : list_for_each_entry(sdev, &shost->__devices, siblings) {
1870 0 : if (sdev->sdev_state == SDEV_DEL)
1871 0 : continue;
1872 0 : spin_unlock_irqrestore(shost->host_lock, flags);
1873 0 : __scsi_remove_device(sdev);
1874 0 : goto restart;
1875 0 : }
1876 0 : spin_unlock_irqrestore(shost->host_lock, flags);
1877 0 : }
1878 :
1879 : /*
1880 : * Function: scsi_get_host_dev()
1881 : *
1882 : * Purpose: Create a scsi_device that points to the host adapter itself.
1883 : *
1884 : * Arguments: SHpnt - Host that needs a scsi_device
1885 : *
1886 : * Lock status: None assumed.
1887 : *
1888 : * Returns: The scsi_device or NULL
1889 : *
1890 : * Notes:
1891 : * Attach a single scsi_device to the Scsi_Host - this should
1892 : * be made to look like a "pseudo-device" that points to the
1893 : * HA itself.
1894 : *
1895 : * Note - this device is not accessible from any high-level
1896 : * drivers (including generics), which is probably not
1897 : * optimal. We can add hooks later to attach
1898 : */
1899 : struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1900 : {
1901 0 : struct scsi_device *sdev = NULL;
1902 0 : struct scsi_target *starget;
1903 0 :
1904 0 : mutex_lock(&shost->scan_mutex);
1905 0 : if (!scsi_host_scan_allowed(shost))
1906 0 : goto out;
1907 0 : starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1908 0 : if (!starget)
1909 0 : goto out;
1910 :
1911 0 : sdev = scsi_alloc_sdev(starget, 0, NULL);
1912 0 : if (sdev)
1913 0 : sdev->borken = 0;
1914 : else
1915 0 : scsi_target_reap(starget);
1916 0 : put_device(&starget->dev);
1917 : out:
1918 0 : mutex_unlock(&shost->scan_mutex);
1919 0 : return sdev;
1920 : }
1921 : EXPORT_SYMBOL(scsi_get_host_dev);
1922 :
1923 : /*
1924 : * Function: scsi_free_host_dev()
1925 : *
1926 : * Purpose: Free a scsi_device that points to the host adapter itself.
1927 : *
1928 : * Arguments: SHpnt - Host that needs a scsi_device
1929 : *
1930 : * Lock status: None assumed.
1931 : *
1932 : * Returns: Nothing
1933 : *
1934 : * Notes:
1935 : */
1936 : void scsi_free_host_dev(struct scsi_device *sdev)
1937 : {
1938 0 : BUG_ON(sdev->id != sdev->host->this_id);
1939 :
1940 0 : __scsi_remove_device(sdev);
1941 0 : }
1942 : EXPORT_SYMBOL(scsi_free_host_dev);
1943 :
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