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1da177e4 | 1 | /* |
d285203c CH |
2 | * Copyright (C) 1999 Eric Youngdale |
3 | * Copyright (C) 2014 Christoph Hellwig | |
1da177e4 LT |
4 | * |
5 | * SCSI queueing library. | |
6 | * Initial versions: Eric Youngdale (eric@andante.org). | |
7 | * Based upon conversations with large numbers | |
8 | * of people at Linux Expo. | |
9 | */ | |
10 | ||
11 | #include <linux/bio.h> | |
d3f46f39 | 12 | #include <linux/bitops.h> |
1da177e4 LT |
13 | #include <linux/blkdev.h> |
14 | #include <linux/completion.h> | |
15 | #include <linux/kernel.h> | |
09703660 | 16 | #include <linux/export.h> |
1da177e4 LT |
17 | #include <linux/init.h> |
18 | #include <linux/pci.h> | |
19 | #include <linux/delay.h> | |
faead26d | 20 | #include <linux/hardirq.h> |
c6132da1 | 21 | #include <linux/scatterlist.h> |
d285203c | 22 | #include <linux/blk-mq.h> |
f1569ff1 | 23 | #include <linux/ratelimit.h> |
a8aa3978 | 24 | #include <asm/unaligned.h> |
1da177e4 LT |
25 | |
26 | #include <scsi/scsi.h> | |
beb40487 | 27 | #include <scsi/scsi_cmnd.h> |
1da177e4 LT |
28 | #include <scsi/scsi_dbg.h> |
29 | #include <scsi/scsi_device.h> | |
30 | #include <scsi/scsi_driver.h> | |
31 | #include <scsi/scsi_eh.h> | |
32 | #include <scsi/scsi_host.h> | |
7aa686d3 | 33 | #include <scsi/scsi_transport.h> /* __scsi_init_queue() */ |
ee14c674 | 34 | #include <scsi/scsi_dh.h> |
1da177e4 | 35 | |
3b5382c4 CH |
36 | #include <trace/events/scsi.h> |
37 | ||
0eebd005 | 38 | #include "scsi_debugfs.h" |
1da177e4 LT |
39 | #include "scsi_priv.h" |
40 | #include "scsi_logging.h" | |
41 | ||
e9c787e6 | 42 | static struct kmem_cache *scsi_sdb_cache; |
0a6ac4ee CH |
43 | static struct kmem_cache *scsi_sense_cache; |
44 | static struct kmem_cache *scsi_sense_isadma_cache; | |
45 | static DEFINE_MUTEX(scsi_sense_cache_mutex); | |
1da177e4 | 46 | |
a45a1f36 BVA |
47 | static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd); |
48 | ||
0a6ac4ee | 49 | static inline struct kmem_cache * |
8e688254 | 50 | scsi_select_sense_cache(bool unchecked_isa_dma) |
0a6ac4ee | 51 | { |
8e688254 | 52 | return unchecked_isa_dma ? scsi_sense_isadma_cache : scsi_sense_cache; |
0a6ac4ee CH |
53 | } |
54 | ||
8e688254 BVA |
55 | static void scsi_free_sense_buffer(bool unchecked_isa_dma, |
56 | unsigned char *sense_buffer) | |
0a6ac4ee | 57 | { |
8e688254 BVA |
58 | kmem_cache_free(scsi_select_sense_cache(unchecked_isa_dma), |
59 | sense_buffer); | |
0a6ac4ee CH |
60 | } |
61 | ||
8e688254 | 62 | static unsigned char *scsi_alloc_sense_buffer(bool unchecked_isa_dma, |
e9c787e6 | 63 | gfp_t gfp_mask, int numa_node) |
0a6ac4ee | 64 | { |
8e688254 BVA |
65 | return kmem_cache_alloc_node(scsi_select_sense_cache(unchecked_isa_dma), |
66 | gfp_mask, numa_node); | |
0a6ac4ee CH |
67 | } |
68 | ||
69 | int scsi_init_sense_cache(struct Scsi_Host *shost) | |
70 | { | |
71 | struct kmem_cache *cache; | |
72 | int ret = 0; | |
73 | ||
8e688254 | 74 | cache = scsi_select_sense_cache(shost->unchecked_isa_dma); |
0a6ac4ee CH |
75 | if (cache) |
76 | return 0; | |
77 | ||
78 | mutex_lock(&scsi_sense_cache_mutex); | |
79 | if (shost->unchecked_isa_dma) { | |
80 | scsi_sense_isadma_cache = | |
81 | kmem_cache_create("scsi_sense_cache(DMA)", | |
82 | SCSI_SENSE_BUFFERSIZE, 0, | |
83 | SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA, NULL); | |
84 | if (!scsi_sense_isadma_cache) | |
85 | ret = -ENOMEM; | |
86 | } else { | |
87 | scsi_sense_cache = | |
88 | kmem_cache_create("scsi_sense_cache", | |
89 | SCSI_SENSE_BUFFERSIZE, 0, SLAB_HWCACHE_ALIGN, NULL); | |
90 | if (!scsi_sense_cache) | |
91 | ret = -ENOMEM; | |
92 | } | |
93 | ||
94 | mutex_unlock(&scsi_sense_cache_mutex); | |
95 | return ret; | |
96 | } | |
6f9a35e2 | 97 | |
a488e749 JA |
98 | /* |
99 | * When to reinvoke queueing after a resource shortage. It's 3 msecs to | |
100 | * not change behaviour from the previous unplug mechanism, experimentation | |
101 | * may prove this needs changing. | |
102 | */ | |
103 | #define SCSI_QUEUE_DELAY 3 | |
104 | ||
de3e8bf3 CH |
105 | static void |
106 | scsi_set_blocked(struct scsi_cmnd *cmd, int reason) | |
1da177e4 LT |
107 | { |
108 | struct Scsi_Host *host = cmd->device->host; | |
109 | struct scsi_device *device = cmd->device; | |
f0c0a376 | 110 | struct scsi_target *starget = scsi_target(device); |
1da177e4 LT |
111 | |
112 | /* | |
d8c37e7b | 113 | * Set the appropriate busy bit for the device/host. |
1da177e4 LT |
114 | * |
115 | * If the host/device isn't busy, assume that something actually | |
116 | * completed, and that we should be able to queue a command now. | |
117 | * | |
118 | * Note that the prior mid-layer assumption that any host could | |
119 | * always queue at least one command is now broken. The mid-layer | |
120 | * will implement a user specifiable stall (see | |
121 | * scsi_host.max_host_blocked and scsi_device.max_device_blocked) | |
122 | * if a command is requeued with no other commands outstanding | |
123 | * either for the device or for the host. | |
124 | */ | |
f0c0a376 MC |
125 | switch (reason) { |
126 | case SCSI_MLQUEUE_HOST_BUSY: | |
cd9070c9 | 127 | atomic_set(&host->host_blocked, host->max_host_blocked); |
f0c0a376 MC |
128 | break; |
129 | case SCSI_MLQUEUE_DEVICE_BUSY: | |
573e5913 | 130 | case SCSI_MLQUEUE_EH_RETRY: |
cd9070c9 CH |
131 | atomic_set(&device->device_blocked, |
132 | device->max_device_blocked); | |
f0c0a376 MC |
133 | break; |
134 | case SCSI_MLQUEUE_TARGET_BUSY: | |
cd9070c9 CH |
135 | atomic_set(&starget->target_blocked, |
136 | starget->max_target_blocked); | |
f0c0a376 MC |
137 | break; |
138 | } | |
de3e8bf3 CH |
139 | } |
140 | ||
d285203c CH |
141 | static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd) |
142 | { | |
143 | struct scsi_device *sdev = cmd->device; | |
d285203c | 144 | |
a45a1f36 BVA |
145 | if (cmd->request->rq_flags & RQF_DONTPREP) { |
146 | cmd->request->rq_flags &= ~RQF_DONTPREP; | |
147 | scsi_mq_uninit_cmd(cmd); | |
148 | } else { | |
149 | WARN_ON_ONCE(true); | |
150 | } | |
2b053aca | 151 | blk_mq_requeue_request(cmd->request, true); |
d285203c CH |
152 | put_device(&sdev->sdev_gendev); |
153 | } | |
154 | ||
de3e8bf3 CH |
155 | /** |
156 | * __scsi_queue_insert - private queue insertion | |
157 | * @cmd: The SCSI command being requeued | |
158 | * @reason: The reason for the requeue | |
159 | * @unbusy: Whether the queue should be unbusied | |
160 | * | |
161 | * This is a private queue insertion. The public interface | |
162 | * scsi_queue_insert() always assumes the queue should be unbusied | |
163 | * because it's always called before the completion. This function is | |
164 | * for a requeue after completion, which should only occur in this | |
165 | * file. | |
166 | */ | |
167 | static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, int unbusy) | |
168 | { | |
169 | struct scsi_device *device = cmd->device; | |
170 | struct request_queue *q = device->request_queue; | |
171 | unsigned long flags; | |
172 | ||
173 | SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd, | |
174 | "Inserting command %p into mlqueue\n", cmd)); | |
175 | ||
176 | scsi_set_blocked(cmd, reason); | |
1da177e4 | 177 | |
1da177e4 LT |
178 | /* |
179 | * Decrement the counters, since these commands are no longer | |
180 | * active on the host/device. | |
181 | */ | |
4f5299ac JB |
182 | if (unbusy) |
183 | scsi_device_unbusy(device); | |
1da177e4 LT |
184 | |
185 | /* | |
a1bf9d1d | 186 | * Requeue this command. It will go before all other commands |
b485462a BVA |
187 | * that are already in the queue. Schedule requeue work under |
188 | * lock such that the kblockd_schedule_work() call happens | |
189 | * before blk_cleanup_queue() finishes. | |
a488e749 | 190 | */ |
644373a4 | 191 | cmd->result = 0; |
d285203c CH |
192 | if (q->mq_ops) { |
193 | scsi_mq_requeue_cmd(cmd); | |
194 | return; | |
195 | } | |
a1bf9d1d | 196 | spin_lock_irqsave(q->queue_lock, flags); |
59897dad | 197 | blk_requeue_request(q, cmd->request); |
59c3d45e | 198 | kblockd_schedule_work(&device->requeue_work); |
b485462a | 199 | spin_unlock_irqrestore(q->queue_lock, flags); |
1da177e4 LT |
200 | } |
201 | ||
4f5299ac JB |
202 | /* |
203 | * Function: scsi_queue_insert() | |
204 | * | |
205 | * Purpose: Insert a command in the midlevel queue. | |
206 | * | |
207 | * Arguments: cmd - command that we are adding to queue. | |
208 | * reason - why we are inserting command to queue. | |
209 | * | |
210 | * Lock status: Assumed that lock is not held upon entry. | |
211 | * | |
212 | * Returns: Nothing. | |
213 | * | |
214 | * Notes: We do this for one of two cases. Either the host is busy | |
215 | * and it cannot accept any more commands for the time being, | |
216 | * or the device returned QUEUE_FULL and can accept no more | |
217 | * commands. | |
218 | * Notes: This could be called either from an interrupt context or a | |
219 | * normal process context. | |
220 | */ | |
84feb166 | 221 | void scsi_queue_insert(struct scsi_cmnd *cmd, int reason) |
4f5299ac | 222 | { |
84feb166 | 223 | __scsi_queue_insert(cmd, reason, 1); |
4f5299ac | 224 | } |
e8064021 | 225 | |
76aaf87b CH |
226 | |
227 | /** | |
228 | * scsi_execute - insert request and wait for the result | |
229 | * @sdev: scsi device | |
230 | * @cmd: scsi command | |
231 | * @data_direction: data direction | |
232 | * @buffer: data buffer | |
233 | * @bufflen: len of buffer | |
234 | * @sense: optional sense buffer | |
235 | * @sshdr: optional decoded sense header | |
236 | * @timeout: request timeout in seconds | |
237 | * @retries: number of times to retry request | |
238 | * @flags: flags for ->cmd_flags | |
239 | * @rq_flags: flags for ->rq_flags | |
240 | * @resid: optional residual length | |
241 | * | |
17d5363b CH |
242 | * Returns the scsi_cmnd result field if a command was executed, or a negative |
243 | * Linux error code if we didn't get that far. | |
76aaf87b CH |
244 | */ |
245 | int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd, | |
33aa687d | 246 | int data_direction, void *buffer, unsigned bufflen, |
3949e2f0 CH |
247 | unsigned char *sense, struct scsi_sense_hdr *sshdr, |
248 | int timeout, int retries, u64 flags, req_flags_t rq_flags, | |
249 | int *resid) | |
39216033 JB |
250 | { |
251 | struct request *req; | |
82ed4db4 | 252 | struct scsi_request *rq; |
39216033 JB |
253 | int ret = DRIVER_ERROR << 24; |
254 | ||
039c635f | 255 | req = blk_get_request_flags(sdev->request_queue, |
aebf526b | 256 | data_direction == DMA_TO_DEVICE ? |
039c635f | 257 | REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, BLK_MQ_REQ_PREEMPT); |
a492f075 | 258 | if (IS_ERR(req)) |
bfe159a5 | 259 | return ret; |
82ed4db4 | 260 | rq = scsi_req(req); |
39216033 JB |
261 | |
262 | if (bufflen && blk_rq_map_kern(sdev->request_queue, req, | |
71baba4b | 263 | buffer, bufflen, __GFP_RECLAIM)) |
39216033 JB |
264 | goto out; |
265 | ||
82ed4db4 CH |
266 | rq->cmd_len = COMMAND_SIZE(cmd[0]); |
267 | memcpy(rq->cmd, cmd, rq->cmd_len); | |
64c7f1d1 | 268 | rq->retries = retries; |
39216033 | 269 | req->timeout = timeout; |
e8064021 | 270 | req->cmd_flags |= flags; |
039c635f | 271 | req->rq_flags |= rq_flags | RQF_QUIET; |
39216033 JB |
272 | |
273 | /* | |
274 | * head injection *required* here otherwise quiesce won't work | |
275 | */ | |
276 | blk_execute_rq(req->q, NULL, req, 1); | |
277 | ||
bdb2b8ca AS |
278 | /* |
279 | * Some devices (USB mass-storage in particular) may transfer | |
280 | * garbage data together with a residue indicating that the data | |
281 | * is invalid. Prevent the garbage from being misinterpreted | |
282 | * and prevent security leaks by zeroing out the excess data. | |
283 | */ | |
82ed4db4 CH |
284 | if (unlikely(rq->resid_len > 0 && rq->resid_len <= bufflen)) |
285 | memset(buffer + (bufflen - rq->resid_len), 0, rq->resid_len); | |
bdb2b8ca | 286 | |
f4f4e47e | 287 | if (resid) |
82ed4db4 CH |
288 | *resid = rq->resid_len; |
289 | if (sense && rq->sense_len) | |
290 | memcpy(sense, rq->sense, SCSI_SENSE_BUFFERSIZE); | |
3949e2f0 CH |
291 | if (sshdr) |
292 | scsi_normalize_sense(rq->sense, rq->sense_len, sshdr); | |
17d5363b | 293 | ret = rq->result; |
39216033 JB |
294 | out: |
295 | blk_put_request(req); | |
296 | ||
297 | return ret; | |
298 | } | |
33aa687d | 299 | EXPORT_SYMBOL(scsi_execute); |
39216033 | 300 | |
1da177e4 LT |
301 | /* |
302 | * Function: scsi_init_cmd_errh() | |
303 | * | |
304 | * Purpose: Initialize cmd fields related to error handling. | |
305 | * | |
306 | * Arguments: cmd - command that is ready to be queued. | |
307 | * | |
1da177e4 LT |
308 | * Notes: This function has the job of initializing a number of |
309 | * fields related to error handling. Typically this will | |
310 | * be called once for each command, as required. | |
311 | */ | |
631c228c | 312 | static void scsi_init_cmd_errh(struct scsi_cmnd *cmd) |
1da177e4 | 313 | { |
1da177e4 | 314 | cmd->serial_number = 0; |
30b0c37b | 315 | scsi_set_resid(cmd, 0); |
b80ca4f7 | 316 | memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); |
1da177e4 | 317 | if (cmd->cmd_len == 0) |
db4742dd | 318 | cmd->cmd_len = scsi_command_size(cmd->cmnd); |
1da177e4 LT |
319 | } |
320 | ||
321 | void scsi_device_unbusy(struct scsi_device *sdev) | |
322 | { | |
323 | struct Scsi_Host *shost = sdev->host; | |
f0c0a376 | 324 | struct scsi_target *starget = scsi_target(sdev); |
1da177e4 LT |
325 | unsigned long flags; |
326 | ||
74665016 | 327 | atomic_dec(&shost->host_busy); |
2ccbb008 CH |
328 | if (starget->can_queue > 0) |
329 | atomic_dec(&starget->target_busy); | |
74665016 | 330 | |
939647ee | 331 | if (unlikely(scsi_host_in_recovery(shost) && |
74665016 CH |
332 | (shost->host_failed || shost->host_eh_scheduled))) { |
333 | spin_lock_irqsave(shost->host_lock, flags); | |
1da177e4 | 334 | scsi_eh_wakeup(shost); |
74665016 CH |
335 | spin_unlock_irqrestore(shost->host_lock, flags); |
336 | } | |
337 | ||
71e75c97 | 338 | atomic_dec(&sdev->device_busy); |
1da177e4 LT |
339 | } |
340 | ||
d285203c CH |
341 | static void scsi_kick_queue(struct request_queue *q) |
342 | { | |
343 | if (q->mq_ops) | |
344 | blk_mq_start_hw_queues(q); | |
345 | else | |
346 | blk_run_queue(q); | |
347 | } | |
348 | ||
1da177e4 LT |
349 | /* |
350 | * Called for single_lun devices on IO completion. Clear starget_sdev_user, | |
351 | * and call blk_run_queue for all the scsi_devices on the target - | |
352 | * including current_sdev first. | |
353 | * | |
354 | * Called with *no* scsi locks held. | |
355 | */ | |
356 | static void scsi_single_lun_run(struct scsi_device *current_sdev) | |
357 | { | |
358 | struct Scsi_Host *shost = current_sdev->host; | |
359 | struct scsi_device *sdev, *tmp; | |
360 | struct scsi_target *starget = scsi_target(current_sdev); | |
361 | unsigned long flags; | |
362 | ||
363 | spin_lock_irqsave(shost->host_lock, flags); | |
364 | starget->starget_sdev_user = NULL; | |
365 | spin_unlock_irqrestore(shost->host_lock, flags); | |
366 | ||
367 | /* | |
368 | * Call blk_run_queue for all LUNs on the target, starting with | |
369 | * current_sdev. We race with others (to set starget_sdev_user), | |
370 | * but in most cases, we will be first. Ideally, each LU on the | |
371 | * target would get some limited time or requests on the target. | |
372 | */ | |
d285203c | 373 | scsi_kick_queue(current_sdev->request_queue); |
1da177e4 LT |
374 | |
375 | spin_lock_irqsave(shost->host_lock, flags); | |
376 | if (starget->starget_sdev_user) | |
377 | goto out; | |
378 | list_for_each_entry_safe(sdev, tmp, &starget->devices, | |
379 | same_target_siblings) { | |
380 | if (sdev == current_sdev) | |
381 | continue; | |
382 | if (scsi_device_get(sdev)) | |
383 | continue; | |
384 | ||
385 | spin_unlock_irqrestore(shost->host_lock, flags); | |
d285203c | 386 | scsi_kick_queue(sdev->request_queue); |
1da177e4 LT |
387 | spin_lock_irqsave(shost->host_lock, flags); |
388 | ||
389 | scsi_device_put(sdev); | |
390 | } | |
391 | out: | |
392 | spin_unlock_irqrestore(shost->host_lock, flags); | |
393 | } | |
394 | ||
cd9070c9 | 395 | static inline bool scsi_device_is_busy(struct scsi_device *sdev) |
9d112517 | 396 | { |
cd9070c9 CH |
397 | if (atomic_read(&sdev->device_busy) >= sdev->queue_depth) |
398 | return true; | |
399 | if (atomic_read(&sdev->device_blocked) > 0) | |
400 | return true; | |
401 | return false; | |
9d112517 KU |
402 | } |
403 | ||
cd9070c9 | 404 | static inline bool scsi_target_is_busy(struct scsi_target *starget) |
f0c0a376 | 405 | { |
2ccbb008 CH |
406 | if (starget->can_queue > 0) { |
407 | if (atomic_read(&starget->target_busy) >= starget->can_queue) | |
408 | return true; | |
409 | if (atomic_read(&starget->target_blocked) > 0) | |
410 | return true; | |
411 | } | |
cd9070c9 | 412 | return false; |
f0c0a376 MC |
413 | } |
414 | ||
cd9070c9 | 415 | static inline bool scsi_host_is_busy(struct Scsi_Host *shost) |
9d112517 | 416 | { |
cd9070c9 CH |
417 | if (shost->can_queue > 0 && |
418 | atomic_read(&shost->host_busy) >= shost->can_queue) | |
419 | return true; | |
420 | if (atomic_read(&shost->host_blocked) > 0) | |
421 | return true; | |
422 | if (shost->host_self_blocked) | |
423 | return true; | |
424 | return false; | |
9d112517 KU |
425 | } |
426 | ||
21a05df5 | 427 | static void scsi_starved_list_run(struct Scsi_Host *shost) |
1da177e4 | 428 | { |
2a3a59e5 | 429 | LIST_HEAD(starved_list); |
21a05df5 | 430 | struct scsi_device *sdev; |
1da177e4 LT |
431 | unsigned long flags; |
432 | ||
1da177e4 | 433 | spin_lock_irqsave(shost->host_lock, flags); |
2a3a59e5 MC |
434 | list_splice_init(&shost->starved_list, &starved_list); |
435 | ||
436 | while (!list_empty(&starved_list)) { | |
e2eb7244 JB |
437 | struct request_queue *slq; |
438 | ||
1da177e4 LT |
439 | /* |
440 | * As long as shost is accepting commands and we have | |
441 | * starved queues, call blk_run_queue. scsi_request_fn | |
442 | * drops the queue_lock and can add us back to the | |
443 | * starved_list. | |
444 | * | |
445 | * host_lock protects the starved_list and starved_entry. | |
446 | * scsi_request_fn must get the host_lock before checking | |
447 | * or modifying starved_list or starved_entry. | |
448 | */ | |
2a3a59e5 | 449 | if (scsi_host_is_busy(shost)) |
f0c0a376 | 450 | break; |
f0c0a376 | 451 | |
2a3a59e5 MC |
452 | sdev = list_entry(starved_list.next, |
453 | struct scsi_device, starved_entry); | |
454 | list_del_init(&sdev->starved_entry); | |
f0c0a376 MC |
455 | if (scsi_target_is_busy(scsi_target(sdev))) { |
456 | list_move_tail(&sdev->starved_entry, | |
457 | &shost->starved_list); | |
458 | continue; | |
459 | } | |
460 | ||
e2eb7244 JB |
461 | /* |
462 | * Once we drop the host lock, a racing scsi_remove_device() | |
463 | * call may remove the sdev from the starved list and destroy | |
464 | * it and the queue. Mitigate by taking a reference to the | |
465 | * queue and never touching the sdev again after we drop the | |
466 | * host lock. Note: if __scsi_remove_device() invokes | |
467 | * blk_cleanup_queue() before the queue is run from this | |
468 | * function then blk_run_queue() will return immediately since | |
469 | * blk_cleanup_queue() marks the queue with QUEUE_FLAG_DYING. | |
470 | */ | |
471 | slq = sdev->request_queue; | |
472 | if (!blk_get_queue(slq)) | |
473 | continue; | |
474 | spin_unlock_irqrestore(shost->host_lock, flags); | |
475 | ||
d285203c | 476 | scsi_kick_queue(slq); |
e2eb7244 JB |
477 | blk_put_queue(slq); |
478 | ||
479 | spin_lock_irqsave(shost->host_lock, flags); | |
1da177e4 | 480 | } |
2a3a59e5 MC |
481 | /* put any unprocessed entries back */ |
482 | list_splice(&starved_list, &shost->starved_list); | |
1da177e4 | 483 | spin_unlock_irqrestore(shost->host_lock, flags); |
21a05df5 CH |
484 | } |
485 | ||
486 | /* | |
487 | * Function: scsi_run_queue() | |
488 | * | |
489 | * Purpose: Select a proper request queue to serve next | |
490 | * | |
491 | * Arguments: q - last request's queue | |
492 | * | |
493 | * Returns: Nothing | |
494 | * | |
495 | * Notes: The previous command was completely finished, start | |
496 | * a new one if possible. | |
497 | */ | |
498 | static void scsi_run_queue(struct request_queue *q) | |
499 | { | |
500 | struct scsi_device *sdev = q->queuedata; | |
501 | ||
502 | if (scsi_target(sdev)->single_lun) | |
503 | scsi_single_lun_run(sdev); | |
504 | if (!list_empty(&sdev->host->starved_list)) | |
505 | scsi_starved_list_run(sdev->host); | |
1da177e4 | 506 | |
d285203c | 507 | if (q->mq_ops) |
36e3cf27 | 508 | blk_mq_run_hw_queues(q, false); |
d285203c CH |
509 | else |
510 | blk_run_queue(q); | |
1da177e4 LT |
511 | } |
512 | ||
9937a5e2 JA |
513 | void scsi_requeue_run_queue(struct work_struct *work) |
514 | { | |
515 | struct scsi_device *sdev; | |
516 | struct request_queue *q; | |
517 | ||
518 | sdev = container_of(work, struct scsi_device, requeue_work); | |
519 | q = sdev->request_queue; | |
520 | scsi_run_queue(q); | |
521 | } | |
522 | ||
1da177e4 LT |
523 | /* |
524 | * Function: scsi_requeue_command() | |
525 | * | |
526 | * Purpose: Handle post-processing of completed commands. | |
527 | * | |
528 | * Arguments: q - queue to operate on | |
529 | * cmd - command that may need to be requeued. | |
530 | * | |
531 | * Returns: Nothing | |
532 | * | |
533 | * Notes: After command completion, there may be blocks left | |
534 | * over which weren't finished by the previous command | |
535 | * this can be for a number of reasons - the main one is | |
536 | * I/O errors in the middle of the request, in which case | |
537 | * we need to request the blocks that come after the bad | |
538 | * sector. | |
e91442b6 | 539 | * Notes: Upon return, cmd is a stale pointer. |
1da177e4 LT |
540 | */ |
541 | static void scsi_requeue_command(struct request_queue *q, struct scsi_cmnd *cmd) | |
542 | { | |
940f5d47 | 543 | struct scsi_device *sdev = cmd->device; |
e91442b6 | 544 | struct request *req = cmd->request; |
283369cc TH |
545 | unsigned long flags; |
546 | ||
283369cc | 547 | spin_lock_irqsave(q->queue_lock, flags); |
134997a0 CH |
548 | blk_unprep_request(req); |
549 | req->special = NULL; | |
550 | scsi_put_command(cmd); | |
e91442b6 | 551 | blk_requeue_request(q, req); |
283369cc | 552 | spin_unlock_irqrestore(q->queue_lock, flags); |
1da177e4 LT |
553 | |
554 | scsi_run_queue(q); | |
940f5d47 BVA |
555 | |
556 | put_device(&sdev->sdev_gendev); | |
1da177e4 LT |
557 | } |
558 | ||
1da177e4 LT |
559 | void scsi_run_host_queues(struct Scsi_Host *shost) |
560 | { | |
561 | struct scsi_device *sdev; | |
562 | ||
563 | shost_for_each_device(sdev, shost) | |
564 | scsi_run_queue(sdev->request_queue); | |
565 | } | |
566 | ||
d285203c CH |
567 | static void scsi_uninit_cmd(struct scsi_cmnd *cmd) |
568 | { | |
57292b58 | 569 | if (!blk_rq_is_passthrough(cmd->request)) { |
d285203c CH |
570 | struct scsi_driver *drv = scsi_cmd_to_driver(cmd); |
571 | ||
572 | if (drv->uninit_command) | |
573 | drv->uninit_command(cmd); | |
574 | } | |
575 | } | |
576 | ||
577 | static void scsi_mq_free_sgtables(struct scsi_cmnd *cmd) | |
578 | { | |
91dbc08d ML |
579 | struct scsi_data_buffer *sdb; |
580 | ||
d285203c | 581 | if (cmd->sdb.table.nents) |
001d63be | 582 | sg_free_table_chained(&cmd->sdb.table, true); |
91dbc08d ML |
583 | if (cmd->request->next_rq) { |
584 | sdb = cmd->request->next_rq->special; | |
585 | if (sdb) | |
001d63be | 586 | sg_free_table_chained(&sdb->table, true); |
91dbc08d | 587 | } |
d285203c | 588 | if (scsi_prot_sg_count(cmd)) |
001d63be | 589 | sg_free_table_chained(&cmd->prot_sdb->table, true); |
d285203c CH |
590 | } |
591 | ||
592 | static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) | |
593 | { | |
d285203c CH |
594 | scsi_mq_free_sgtables(cmd); |
595 | scsi_uninit_cmd(cmd); | |
2dd6fb59 | 596 | scsi_del_cmd_from_list(cmd); |
d285203c CH |
597 | } |
598 | ||
1da177e4 LT |
599 | /* |
600 | * Function: scsi_release_buffers() | |
601 | * | |
c682adf3 | 602 | * Purpose: Free resources allocate for a scsi_command. |
1da177e4 LT |
603 | * |
604 | * Arguments: cmd - command that we are bailing. | |
605 | * | |
606 | * Lock status: Assumed that no lock is held upon entry. | |
607 | * | |
608 | * Returns: Nothing | |
609 | * | |
610 | * Notes: In the event that an upper level driver rejects a | |
611 | * command, we must release resources allocated during | |
612 | * the __init_io() function. Primarily this would involve | |
c682adf3 | 613 | * the scatter-gather table. |
1da177e4 | 614 | */ |
f1bea55d | 615 | static void scsi_release_buffers(struct scsi_cmnd *cmd) |
1da177e4 | 616 | { |
c682adf3 | 617 | if (cmd->sdb.table.nents) |
001d63be | 618 | sg_free_table_chained(&cmd->sdb.table, false); |
c682adf3 CH |
619 | |
620 | memset(&cmd->sdb, 0, sizeof(cmd->sdb)); | |
621 | ||
622 | if (scsi_prot_sg_count(cmd)) | |
001d63be | 623 | sg_free_table_chained(&cmd->prot_sdb->table, false); |
1da177e4 LT |
624 | } |
625 | ||
c682adf3 CH |
626 | static void scsi_release_bidi_buffers(struct scsi_cmnd *cmd) |
627 | { | |
628 | struct scsi_data_buffer *bidi_sdb = cmd->request->next_rq->special; | |
629 | ||
001d63be | 630 | sg_free_table_chained(&bidi_sdb->table, false); |
c682adf3 CH |
631 | kmem_cache_free(scsi_sdb_cache, bidi_sdb); |
632 | cmd->request->next_rq->special = NULL; | |
633 | } | |
634 | ||
2a842aca | 635 | static bool scsi_end_request(struct request *req, blk_status_t error, |
f6d47e74 CH |
636 | unsigned int bytes, unsigned int bidi_bytes) |
637 | { | |
bed2213d | 638 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
f6d47e74 CH |
639 | struct scsi_device *sdev = cmd->device; |
640 | struct request_queue *q = sdev->request_queue; | |
f6d47e74 CH |
641 | |
642 | if (blk_update_request(req, error, bytes)) | |
643 | return true; | |
644 | ||
645 | /* Bidi request must be completed as a whole */ | |
646 | if (unlikely(bidi_bytes) && | |
647 | blk_update_request(req->next_rq, error, bidi_bytes)) | |
648 | return true; | |
649 | ||
650 | if (blk_queue_add_random(q)) | |
651 | add_disk_randomness(req->rq_disk); | |
652 | ||
64104f70 BVA |
653 | if (!blk_rq_is_scsi(req)) { |
654 | WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED)); | |
655 | cmd->flags &= ~SCMD_INITIALIZED; | |
656 | } | |
657 | ||
d285203c CH |
658 | if (req->mq_ctx) { |
659 | /* | |
c8a446ad | 660 | * In the MQ case the command gets freed by __blk_mq_end_request, |
d285203c CH |
661 | * so we have to do all cleanup that depends on it earlier. |
662 | * | |
663 | * We also can't kick the queues from irq context, so we | |
664 | * will have to defer it to a workqueue. | |
665 | */ | |
666 | scsi_mq_uninit_cmd(cmd); | |
667 | ||
c8a446ad | 668 | __blk_mq_end_request(req, error); |
d285203c CH |
669 | |
670 | if (scsi_target(sdev)->single_lun || | |
671 | !list_empty(&sdev->host->starved_list)) | |
672 | kblockd_schedule_work(&sdev->requeue_work); | |
673 | else | |
36e3cf27 | 674 | blk_mq_run_hw_queues(q, true); |
d285203c CH |
675 | } else { |
676 | unsigned long flags; | |
677 | ||
f81426a8 DG |
678 | if (bidi_bytes) |
679 | scsi_release_bidi_buffers(cmd); | |
e9c787e6 CH |
680 | scsi_release_buffers(cmd); |
681 | scsi_put_command(cmd); | |
f81426a8 | 682 | |
d285203c CH |
683 | spin_lock_irqsave(q->queue_lock, flags); |
684 | blk_finish_request(req, error); | |
685 | spin_unlock_irqrestore(q->queue_lock, flags); | |
686 | ||
bb3ec62a | 687 | scsi_run_queue(q); |
d285203c | 688 | } |
f6d47e74 | 689 | |
bb3ec62a | 690 | put_device(&sdev->sdev_gendev); |
f6d47e74 CH |
691 | return false; |
692 | } | |
693 | ||
0f7f6234 HR |
694 | /** |
695 | * __scsi_error_from_host_byte - translate SCSI error code into errno | |
696 | * @cmd: SCSI command (unused) | |
697 | * @result: scsi error code | |
698 | * | |
2a842aca | 699 | * Translate SCSI error code into block errors. |
0f7f6234 | 700 | */ |
2a842aca CH |
701 | static blk_status_t __scsi_error_from_host_byte(struct scsi_cmnd *cmd, |
702 | int result) | |
63583cca | 703 | { |
2a842aca | 704 | switch (host_byte(result)) { |
63583cca | 705 | case DID_TRANSPORT_FAILFAST: |
2a842aca | 706 | return BLK_STS_TRANSPORT; |
63583cca | 707 | case DID_TARGET_FAILURE: |
2082ebc4 | 708 | set_host_byte(cmd, DID_OK); |
2a842aca | 709 | return BLK_STS_TARGET; |
63583cca | 710 | case DID_NEXUS_FAILURE: |
2a842aca | 711 | return BLK_STS_NEXUS; |
a9d6ceb8 HR |
712 | case DID_ALLOC_FAILURE: |
713 | set_host_byte(cmd, DID_OK); | |
2a842aca | 714 | return BLK_STS_NOSPC; |
7e782af5 HR |
715 | case DID_MEDIUM_ERROR: |
716 | set_host_byte(cmd, DID_OK); | |
2a842aca | 717 | return BLK_STS_MEDIUM; |
63583cca | 718 | default: |
2a842aca | 719 | return BLK_STS_IOERR; |
63583cca | 720 | } |
63583cca HR |
721 | } |
722 | ||
1da177e4 LT |
723 | /* |
724 | * Function: scsi_io_completion() | |
725 | * | |
726 | * Purpose: Completion processing for block device I/O requests. | |
727 | * | |
728 | * Arguments: cmd - command that is finished. | |
729 | * | |
730 | * Lock status: Assumed that no lock is held upon entry. | |
731 | * | |
732 | * Returns: Nothing | |
733 | * | |
bc85dc50 CH |
734 | * Notes: We will finish off the specified number of sectors. If we |
735 | * are done, the command block will be released and the queue | |
736 | * function will be goosed. If we are not done then we have to | |
b60af5b0 | 737 | * figure out what to do next: |
1da177e4 | 738 | * |
b60af5b0 AS |
739 | * a) We can call scsi_requeue_command(). The request |
740 | * will be unprepared and put back on the queue. Then | |
741 | * a new command will be created for it. This should | |
742 | * be used if we made forward progress, or if we want | |
743 | * to switch from READ(10) to READ(6) for example. | |
1da177e4 | 744 | * |
bc85dc50 | 745 | * b) We can call __scsi_queue_insert(). The request will |
b60af5b0 AS |
746 | * be put back on the queue and retried using the same |
747 | * command as before, possibly after a delay. | |
748 | * | |
f6d47e74 | 749 | * c) We can call scsi_end_request() with -EIO to fail |
b60af5b0 | 750 | * the remainder of the request. |
1da177e4 | 751 | */ |
03aba2f7 | 752 | void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) |
1da177e4 LT |
753 | { |
754 | int result = cmd->result; | |
165125e1 | 755 | struct request_queue *q = cmd->device->request_queue; |
1da177e4 | 756 | struct request *req = cmd->request; |
2a842aca | 757 | blk_status_t error = BLK_STS_OK; |
1da177e4 | 758 | struct scsi_sense_hdr sshdr; |
4753cbc0 | 759 | bool sense_valid = false; |
c11c004b | 760 | int sense_deferred = 0, level = 0; |
b60af5b0 AS |
761 | enum {ACTION_FAIL, ACTION_REPREP, ACTION_RETRY, |
762 | ACTION_DELAYED_RETRY} action; | |
ee60b2c5 | 763 | unsigned long wait_for = (cmd->allowed + 1) * req->timeout; |
1da177e4 | 764 | |
1da177e4 LT |
765 | if (result) { |
766 | sense_valid = scsi_command_normalize_sense(cmd, &sshdr); | |
767 | if (sense_valid) | |
768 | sense_deferred = scsi_sense_is_deferred(&sshdr); | |
769 | } | |
631c228c | 770 | |
57292b58 | 771 | if (blk_rq_is_passthrough(req)) { |
1da177e4 | 772 | if (result) { |
82ed4db4 | 773 | if (sense_valid) { |
1da177e4 LT |
774 | /* |
775 | * SG_IO wants current and deferred errors | |
776 | */ | |
82ed4db4 CH |
777 | scsi_req(req)->sense_len = |
778 | min(8 + cmd->sense_buffer[7], | |
779 | SCSI_SENSE_BUFFERSIZE); | |
1da177e4 | 780 | } |
fa8e36c3 | 781 | if (!sense_deferred) |
63583cca | 782 | error = __scsi_error_from_host_byte(cmd, result); |
b22f687d | 783 | } |
27c41973 MS |
784 | /* |
785 | * __scsi_error_from_host_byte may have reset the host_byte | |
786 | */ | |
17d5363b | 787 | scsi_req(req)->result = cmd->result; |
82ed4db4 | 788 | scsi_req(req)->resid_len = scsi_get_resid(cmd); |
e6bb7a96 | 789 | |
6f9a35e2 | 790 | if (scsi_bidi_cmnd(cmd)) { |
e6bb7a96 FT |
791 | /* |
792 | * Bidi commands Must be complete as a whole, | |
793 | * both sides at once. | |
794 | */ | |
82ed4db4 | 795 | scsi_req(req->next_rq)->resid_len = scsi_in(cmd)->resid; |
2a842aca | 796 | if (scsi_end_request(req, BLK_STS_OK, blk_rq_bytes(req), |
f6d47e74 CH |
797 | blk_rq_bytes(req->next_rq))) |
798 | BUG(); | |
6f9a35e2 BH |
799 | return; |
800 | } | |
89fb4cd1 JB |
801 | } else if (blk_rq_bytes(req) == 0 && result && !sense_deferred) { |
802 | /* | |
aebf526b | 803 | * Flush commands do not transfers any data, and thus cannot use |
89fb4cd1 JB |
804 | * good_bytes != blk_rq_bytes(req) as the signal for an error. |
805 | * This sets the error explicitly for the problem case. | |
806 | */ | |
807 | error = __scsi_error_from_host_byte(cmd, result); | |
1da177e4 LT |
808 | } |
809 | ||
57292b58 | 810 | /* no bidi support for !blk_rq_is_passthrough yet */ |
33659ebb | 811 | BUG_ON(blk_bidi_rq(req)); |
30b0c37b | 812 | |
1da177e4 LT |
813 | /* |
814 | * Next deal with any sectors which we were able to correctly | |
815 | * handle. | |
816 | */ | |
91921e01 HR |
817 | SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, cmd, |
818 | "%u sectors total, %d bytes done.\n", | |
819 | blk_rq_sectors(req), good_bytes)); | |
d6b0c537 | 820 | |
a9bddd74 | 821 | /* |
aebf526b CH |
822 | * Recovered errors need reporting, but they're always treated as |
823 | * success, so fiddle the result code here. For passthrough requests | |
17d5363b | 824 | * we already took a copy of the original into sreq->result which |
a9bddd74 JB |
825 | * is what gets returned to the user |
826 | */ | |
e7efe593 DG |
827 | if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) { |
828 | /* if ATA PASS-THROUGH INFORMATION AVAILABLE skip | |
829 | * print since caller wants ATA registers. Only occurs on | |
830 | * SCSI ATA PASS_THROUGH commands when CK_COND=1 | |
831 | */ | |
832 | if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d)) | |
833 | ; | |
e8064021 | 834 | else if (!(req->rq_flags & RQF_QUIET)) |
d811b848 | 835 | scsi_print_sense(cmd); |
a9bddd74 | 836 | result = 0; |
aebf526b | 837 | /* for passthrough error may be set */ |
2a842aca | 838 | error = BLK_STS_OK; |
a9bddd74 JB |
839 | } |
840 | ||
841 | /* | |
a621bac3 JB |
842 | * special case: failed zero length commands always need to |
843 | * drop down into the retry code. Otherwise, if we finished | |
844 | * all bytes in the request we are done now. | |
d6b0c537 | 845 | */ |
a621bac3 JB |
846 | if (!(blk_rq_bytes(req) == 0 && error) && |
847 | !scsi_end_request(req, error, good_bytes, 0)) | |
f6d47e74 | 848 | return; |
bc85dc50 CH |
849 | |
850 | /* | |
851 | * Kill remainder if no retrys. | |
852 | */ | |
853 | if (error && scsi_noretry_cmd(cmd)) { | |
f6d47e74 CH |
854 | if (scsi_end_request(req, error, blk_rq_bytes(req), 0)) |
855 | BUG(); | |
856 | return; | |
bc85dc50 CH |
857 | } |
858 | ||
859 | /* | |
860 | * If there had been no error, but we have leftover bytes in the | |
861 | * requeues just queue the command up again. | |
d6b0c537 | 862 | */ |
bc85dc50 CH |
863 | if (result == 0) |
864 | goto requeue; | |
03aba2f7 | 865 | |
63583cca | 866 | error = __scsi_error_from_host_byte(cmd, result); |
3e695f89 | 867 | |
b60af5b0 AS |
868 | if (host_byte(result) == DID_RESET) { |
869 | /* Third party bus reset or reset for error recovery | |
870 | * reasons. Just retry the command and see what | |
871 | * happens. | |
872 | */ | |
873 | action = ACTION_RETRY; | |
874 | } else if (sense_valid && !sense_deferred) { | |
1da177e4 LT |
875 | switch (sshdr.sense_key) { |
876 | case UNIT_ATTENTION: | |
877 | if (cmd->device->removable) { | |
03aba2f7 | 878 | /* Detected disc change. Set a bit |
1da177e4 LT |
879 | * and quietly refuse further access. |
880 | */ | |
881 | cmd->device->changed = 1; | |
b60af5b0 | 882 | action = ACTION_FAIL; |
1da177e4 | 883 | } else { |
03aba2f7 LT |
884 | /* Must have been a power glitch, or a |
885 | * bus reset. Could not have been a | |
886 | * media change, so we just retry the | |
b60af5b0 | 887 | * command and see what happens. |
03aba2f7 | 888 | */ |
b60af5b0 | 889 | action = ACTION_RETRY; |
1da177e4 LT |
890 | } |
891 | break; | |
892 | case ILLEGAL_REQUEST: | |
03aba2f7 LT |
893 | /* If we had an ILLEGAL REQUEST returned, then |
894 | * we may have performed an unsupported | |
895 | * command. The only thing this should be | |
896 | * would be a ten byte read where only a six | |
897 | * byte read was supported. Also, on a system | |
898 | * where READ CAPACITY failed, we may have | |
899 | * read past the end of the disk. | |
900 | */ | |
26a68019 JA |
901 | if ((cmd->device->use_10_for_rw && |
902 | sshdr.asc == 0x20 && sshdr.ascq == 0x00) && | |
1da177e4 LT |
903 | (cmd->cmnd[0] == READ_10 || |
904 | cmd->cmnd[0] == WRITE_10)) { | |
b60af5b0 | 905 | /* This will issue a new 6-byte command. */ |
1da177e4 | 906 | cmd->device->use_10_for_rw = 0; |
b60af5b0 | 907 | action = ACTION_REPREP; |
3e695f89 | 908 | } else if (sshdr.asc == 0x10) /* DIX */ { |
3e695f89 | 909 | action = ACTION_FAIL; |
2a842aca | 910 | error = BLK_STS_PROTECTION; |
c98a0eb0 | 911 | /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */ |
5db44863 | 912 | } else if (sshdr.asc == 0x20 || sshdr.asc == 0x24) { |
c98a0eb0 | 913 | action = ACTION_FAIL; |
2a842aca | 914 | error = BLK_STS_TARGET; |
b60af5b0 AS |
915 | } else |
916 | action = ACTION_FAIL; | |
917 | break; | |
511e44f4 | 918 | case ABORTED_COMMAND: |
126c0982 | 919 | action = ACTION_FAIL; |
e6c11dbb | 920 | if (sshdr.asc == 0x10) /* DIF */ |
2a842aca | 921 | error = BLK_STS_PROTECTION; |
1da177e4 LT |
922 | break; |
923 | case NOT_READY: | |
03aba2f7 | 924 | /* If the device is in the process of becoming |
f3e93f73 | 925 | * ready, or has a temporary blockage, retry. |
1da177e4 | 926 | */ |
f3e93f73 JB |
927 | if (sshdr.asc == 0x04) { |
928 | switch (sshdr.ascq) { | |
929 | case 0x01: /* becoming ready */ | |
930 | case 0x04: /* format in progress */ | |
931 | case 0x05: /* rebuild in progress */ | |
932 | case 0x06: /* recalculation in progress */ | |
933 | case 0x07: /* operation in progress */ | |
934 | case 0x08: /* Long write in progress */ | |
935 | case 0x09: /* self test in progress */ | |
d8705f11 | 936 | case 0x14: /* space allocation in progress */ |
b60af5b0 | 937 | action = ACTION_DELAYED_RETRY; |
f3e93f73 | 938 | break; |
3dbf6a54 | 939 | default: |
3dbf6a54 AS |
940 | action = ACTION_FAIL; |
941 | break; | |
f3e93f73 | 942 | } |
e6c11dbb | 943 | } else |
b60af5b0 | 944 | action = ACTION_FAIL; |
b60af5b0 | 945 | break; |
1da177e4 | 946 | case VOLUME_OVERFLOW: |
03aba2f7 | 947 | /* See SSC3rXX or current. */ |
b60af5b0 AS |
948 | action = ACTION_FAIL; |
949 | break; | |
1da177e4 | 950 | default: |
b60af5b0 | 951 | action = ACTION_FAIL; |
1da177e4 LT |
952 | break; |
953 | } | |
e6c11dbb | 954 | } else |
b60af5b0 | 955 | action = ACTION_FAIL; |
b60af5b0 | 956 | |
ee60b2c5 | 957 | if (action != ACTION_FAIL && |
e6c11dbb | 958 | time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) |
ee60b2c5 | 959 | action = ACTION_FAIL; |
ee60b2c5 | 960 | |
b60af5b0 AS |
961 | switch (action) { |
962 | case ACTION_FAIL: | |
963 | /* Give up and fail the remainder of the request */ | |
e8064021 | 964 | if (!(req->rq_flags & RQF_QUIET)) { |
f1569ff1 HR |
965 | static DEFINE_RATELIMIT_STATE(_rs, |
966 | DEFAULT_RATELIMIT_INTERVAL, | |
967 | DEFAULT_RATELIMIT_BURST); | |
968 | ||
969 | if (unlikely(scsi_logging_level)) | |
970 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, | |
971 | SCSI_LOG_MLCOMPLETE_BITS); | |
972 | ||
973 | /* | |
974 | * if logging is enabled the failure will be printed | |
975 | * in scsi_log_completion(), so avoid duplicate messages | |
976 | */ | |
977 | if (!level && __ratelimit(&_rs)) { | |
978 | scsi_print_result(cmd, NULL, FAILED); | |
979 | if (driver_byte(result) & DRIVER_SENSE) | |
980 | scsi_print_sense(cmd); | |
981 | scsi_print_command(cmd); | |
982 | } | |
3173d8c3 | 983 | } |
f6d47e74 CH |
984 | if (!scsi_end_request(req, error, blk_rq_err_bytes(req), 0)) |
985 | return; | |
bc85dc50 | 986 | /*FALLTHRU*/ |
b60af5b0 | 987 | case ACTION_REPREP: |
bc85dc50 | 988 | requeue: |
b60af5b0 AS |
989 | /* Unprep the request and put it back at the head of the queue. |
990 | * A new command will be prepared and issued. | |
991 | */ | |
d285203c | 992 | if (q->mq_ops) { |
d285203c CH |
993 | scsi_mq_requeue_cmd(cmd); |
994 | } else { | |
995 | scsi_release_buffers(cmd); | |
996 | scsi_requeue_command(q, cmd); | |
997 | } | |
b60af5b0 AS |
998 | break; |
999 | case ACTION_RETRY: | |
1000 | /* Retry the same command immediately */ | |
4f5299ac | 1001 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY, 0); |
b60af5b0 AS |
1002 | break; |
1003 | case ACTION_DELAYED_RETRY: | |
1004 | /* Retry the same command after a delay */ | |
4f5299ac | 1005 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, 0); |
b60af5b0 | 1006 | break; |
1da177e4 LT |
1007 | } |
1008 | } | |
1da177e4 | 1009 | |
3c356bde | 1010 | static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb) |
1da177e4 | 1011 | { |
6f9a35e2 | 1012 | int count; |
1da177e4 LT |
1013 | |
1014 | /* | |
3b003157 | 1015 | * If sg table allocation fails, requeue request later. |
1da177e4 | 1016 | */ |
f9d03f96 CH |
1017 | if (unlikely(sg_alloc_table_chained(&sdb->table, |
1018 | blk_rq_nr_phys_segments(req), sdb->table.sgl))) | |
1da177e4 | 1019 | return BLKPREP_DEFER; |
1da177e4 | 1020 | |
1da177e4 LT |
1021 | /* |
1022 | * Next, walk the list, and fill in the addresses and sizes of | |
1023 | * each segment. | |
1024 | */ | |
30b0c37b BH |
1025 | count = blk_rq_map_sg(req->q, req, sdb->table.sgl); |
1026 | BUG_ON(count > sdb->table.nents); | |
1027 | sdb->table.nents = count; | |
fd102b12 | 1028 | sdb->length = blk_rq_payload_bytes(req); |
4a03d90e | 1029 | return BLKPREP_OK; |
1da177e4 | 1030 | } |
6f9a35e2 BH |
1031 | |
1032 | /* | |
1033 | * Function: scsi_init_io() | |
1034 | * | |
1035 | * Purpose: SCSI I/O initialize function. | |
1036 | * | |
1037 | * Arguments: cmd - Command descriptor we wish to initialize | |
1038 | * | |
1039 | * Returns: 0 on success | |
1040 | * BLKPREP_DEFER if the failure is retryable | |
1041 | * BLKPREP_KILL if the failure is fatal | |
1042 | */ | |
3c356bde | 1043 | int scsi_init_io(struct scsi_cmnd *cmd) |
6f9a35e2 | 1044 | { |
5e012aad | 1045 | struct scsi_device *sdev = cmd->device; |
13f05c8d | 1046 | struct request *rq = cmd->request; |
d285203c | 1047 | bool is_mq = (rq->mq_ctx != NULL); |
e7661a8e | 1048 | int error = BLKPREP_KILL; |
13f05c8d | 1049 | |
fd3fc0b4 | 1050 | if (WARN_ON_ONCE(!blk_rq_nr_phys_segments(rq))) |
e7661a8e | 1051 | goto err_exit; |
635d98b1 | 1052 | |
3c356bde | 1053 | error = scsi_init_sgtable(rq, &cmd->sdb); |
6f9a35e2 BH |
1054 | if (error) |
1055 | goto err_exit; | |
1056 | ||
13f05c8d | 1057 | if (blk_bidi_rq(rq)) { |
d285203c CH |
1058 | if (!rq->q->mq_ops) { |
1059 | struct scsi_data_buffer *bidi_sdb = | |
1060 | kmem_cache_zalloc(scsi_sdb_cache, GFP_ATOMIC); | |
1061 | if (!bidi_sdb) { | |
1062 | error = BLKPREP_DEFER; | |
1063 | goto err_exit; | |
1064 | } | |
1065 | ||
1066 | rq->next_rq->special = bidi_sdb; | |
6f9a35e2 BH |
1067 | } |
1068 | ||
3c356bde | 1069 | error = scsi_init_sgtable(rq->next_rq, rq->next_rq->special); |
6f9a35e2 BH |
1070 | if (error) |
1071 | goto err_exit; | |
1072 | } | |
1073 | ||
13f05c8d | 1074 | if (blk_integrity_rq(rq)) { |
7027ad72 MP |
1075 | struct scsi_data_buffer *prot_sdb = cmd->prot_sdb; |
1076 | int ivecs, count; | |
1077 | ||
91724c20 EM |
1078 | if (prot_sdb == NULL) { |
1079 | /* | |
1080 | * This can happen if someone (e.g. multipath) | |
1081 | * queues a command to a device on an adapter | |
1082 | * that does not support DIX. | |
1083 | */ | |
1084 | WARN_ON_ONCE(1); | |
1085 | error = BLKPREP_KILL; | |
1086 | goto err_exit; | |
1087 | } | |
1088 | ||
13f05c8d | 1089 | ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio); |
7027ad72 | 1090 | |
001d63be | 1091 | if (sg_alloc_table_chained(&prot_sdb->table, ivecs, |
22cc3d4c | 1092 | prot_sdb->table.sgl)) { |
7027ad72 MP |
1093 | error = BLKPREP_DEFER; |
1094 | goto err_exit; | |
1095 | } | |
1096 | ||
13f05c8d | 1097 | count = blk_rq_map_integrity_sg(rq->q, rq->bio, |
7027ad72 MP |
1098 | prot_sdb->table.sgl); |
1099 | BUG_ON(unlikely(count > ivecs)); | |
13f05c8d | 1100 | BUG_ON(unlikely(count > queue_max_integrity_segments(rq->q))); |
7027ad72 MP |
1101 | |
1102 | cmd->prot_sdb = prot_sdb; | |
1103 | cmd->prot_sdb->table.nents = count; | |
1104 | } | |
1105 | ||
d285203c | 1106 | return BLKPREP_OK; |
6f9a35e2 | 1107 | err_exit: |
d285203c CH |
1108 | if (is_mq) { |
1109 | scsi_mq_free_sgtables(cmd); | |
1110 | } else { | |
1111 | scsi_release_buffers(cmd); | |
1112 | cmd->request->special = NULL; | |
1113 | scsi_put_command(cmd); | |
1114 | put_device(&sdev->sdev_gendev); | |
1115 | } | |
6f9a35e2 BH |
1116 | return error; |
1117 | } | |
bb52d82f | 1118 | EXPORT_SYMBOL(scsi_init_io); |
1da177e4 | 1119 | |
ca18d6f7 | 1120 | /** |
832889f5 | 1121 | * scsi_initialize_rq - initialize struct scsi_cmnd partially |
35c0506f | 1122 | * @rq: Request associated with the SCSI command to be initialized. |
ca18d6f7 | 1123 | * |
832889f5 BVA |
1124 | * This function initializes the members of struct scsi_cmnd that must be |
1125 | * initialized before request processing starts and that won't be | |
1126 | * reinitialized if a SCSI command is requeued. | |
1127 | * | |
64104f70 BVA |
1128 | * Called from inside blk_get_request() for pass-through requests and from |
1129 | * inside scsi_init_command() for filesystem requests. | |
ca18d6f7 BVA |
1130 | */ |
1131 | void scsi_initialize_rq(struct request *rq) | |
1132 | { | |
c8d9cf22 BVA |
1133 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
1134 | ||
1135 | scsi_req_init(&cmd->req); | |
832889f5 BVA |
1136 | cmd->jiffies_at_alloc = jiffies; |
1137 | cmd->retries = 0; | |
ca18d6f7 BVA |
1138 | } |
1139 | EXPORT_SYMBOL(scsi_initialize_rq); | |
1140 | ||
2dd6fb59 BVA |
1141 | /* Add a command to the list used by the aacraid and dpt_i2o drivers */ |
1142 | void scsi_add_cmd_to_list(struct scsi_cmnd *cmd) | |
1143 | { | |
1144 | struct scsi_device *sdev = cmd->device; | |
1145 | struct Scsi_Host *shost = sdev->host; | |
1146 | unsigned long flags; | |
1147 | ||
1148 | if (shost->use_cmd_list) { | |
1149 | spin_lock_irqsave(&sdev->list_lock, flags); | |
1150 | list_add_tail(&cmd->list, &sdev->cmd_list); | |
1151 | spin_unlock_irqrestore(&sdev->list_lock, flags); | |
1152 | } | |
1153 | } | |
1154 | ||
1155 | /* Remove a command from the list used by the aacraid and dpt_i2o drivers */ | |
1156 | void scsi_del_cmd_from_list(struct scsi_cmnd *cmd) | |
1157 | { | |
1158 | struct scsi_device *sdev = cmd->device; | |
1159 | struct Scsi_Host *shost = sdev->host; | |
1160 | unsigned long flags; | |
1161 | ||
1162 | if (shost->use_cmd_list) { | |
1163 | spin_lock_irqsave(&sdev->list_lock, flags); | |
1164 | BUG_ON(list_empty(&cmd->list)); | |
1165 | list_del_init(&cmd->list); | |
1166 | spin_unlock_irqrestore(&sdev->list_lock, flags); | |
1167 | } | |
1168 | } | |
1169 | ||
ca18d6f7 | 1170 | /* Called after a request has been started. */ |
e9c787e6 | 1171 | void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd) |
3b003157 | 1172 | { |
e9c787e6 CH |
1173 | void *buf = cmd->sense_buffer; |
1174 | void *prot = cmd->prot_sdb; | |
64104f70 BVA |
1175 | struct request *rq = blk_mq_rq_from_pdu(cmd); |
1176 | unsigned int flags = cmd->flags & SCMD_PRESERVED_FLAGS; | |
832889f5 BVA |
1177 | unsigned long jiffies_at_alloc; |
1178 | int retries; | |
64104f70 BVA |
1179 | |
1180 | if (!blk_rq_is_scsi(rq) && !(flags & SCMD_INITIALIZED)) { | |
1181 | flags |= SCMD_INITIALIZED; | |
1182 | scsi_initialize_rq(rq); | |
1183 | } | |
3b003157 | 1184 | |
832889f5 BVA |
1185 | jiffies_at_alloc = cmd->jiffies_at_alloc; |
1186 | retries = cmd->retries; | |
82ed4db4 CH |
1187 | /* zero out the cmd, except for the embedded scsi_request */ |
1188 | memset((char *)cmd + sizeof(cmd->req), 0, | |
ee524236 | 1189 | sizeof(*cmd) - sizeof(cmd->req) + dev->host->hostt->cmd_size); |
3b003157 | 1190 | |
e9c787e6 CH |
1191 | cmd->device = dev; |
1192 | cmd->sense_buffer = buf; | |
1193 | cmd->prot_sdb = prot; | |
64104f70 | 1194 | cmd->flags = flags; |
e9c787e6 | 1195 | INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler); |
832889f5 BVA |
1196 | cmd->jiffies_at_alloc = jiffies_at_alloc; |
1197 | cmd->retries = retries; | |
64a87b24 | 1198 | |
2dd6fb59 | 1199 | scsi_add_cmd_to_list(cmd); |
3b003157 CH |
1200 | } |
1201 | ||
aebf526b | 1202 | static int scsi_setup_scsi_cmnd(struct scsi_device *sdev, struct request *req) |
7b16318d | 1203 | { |
bed2213d | 1204 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
3b003157 CH |
1205 | |
1206 | /* | |
aebf526b | 1207 | * Passthrough requests may transfer data, in which case they must |
3b003157 CH |
1208 | * a bio attached to them. Or they might contain a SCSI command |
1209 | * that does not transfer data, in which case they may optionally | |
1210 | * submit a request without an attached bio. | |
1211 | */ | |
1212 | if (req->bio) { | |
3c356bde | 1213 | int ret = scsi_init_io(cmd); |
3b003157 CH |
1214 | if (unlikely(ret)) |
1215 | return ret; | |
1216 | } else { | |
b0790410 | 1217 | BUG_ON(blk_rq_bytes(req)); |
3b003157 | 1218 | |
30b0c37b | 1219 | memset(&cmd->sdb, 0, sizeof(cmd->sdb)); |
3b003157 | 1220 | } |
7b16318d | 1221 | |
82ed4db4 CH |
1222 | cmd->cmd_len = scsi_req(req)->cmd_len; |
1223 | cmd->cmnd = scsi_req(req)->cmd; | |
b0790410 | 1224 | cmd->transfersize = blk_rq_bytes(req); |
64c7f1d1 | 1225 | cmd->allowed = scsi_req(req)->retries; |
3b003157 | 1226 | return BLKPREP_OK; |
7b16318d | 1227 | } |
7b16318d | 1228 | |
3b003157 | 1229 | /* |
aebf526b | 1230 | * Setup a normal block command. These are simple request from filesystems |
3868cf8e | 1231 | * that still need to be translated to SCSI CDBs from the ULD. |
3b003157 | 1232 | */ |
3868cf8e | 1233 | static int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req) |
1da177e4 | 1234 | { |
bed2213d | 1235 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
a6a8d9f8 | 1236 | |
ee14c674 CH |
1237 | if (unlikely(sdev->handler && sdev->handler->prep_fn)) { |
1238 | int ret = sdev->handler->prep_fn(sdev, req); | |
a6a8d9f8 CS |
1239 | if (ret != BLKPREP_OK) |
1240 | return ret; | |
1241 | } | |
1242 | ||
82ed4db4 | 1243 | cmd->cmnd = scsi_req(req)->cmd = scsi_req(req)->__cmd; |
64a87b24 | 1244 | memset(cmd->cmnd, 0, BLK_MAX_CDB); |
3868cf8e | 1245 | return scsi_cmd_to_driver(cmd)->init_command(cmd); |
3b003157 CH |
1246 | } |
1247 | ||
6af7a4ff CH |
1248 | static int scsi_setup_cmnd(struct scsi_device *sdev, struct request *req) |
1249 | { | |
bed2213d | 1250 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
6af7a4ff CH |
1251 | |
1252 | if (!blk_rq_bytes(req)) | |
1253 | cmd->sc_data_direction = DMA_NONE; | |
1254 | else if (rq_data_dir(req) == WRITE) | |
1255 | cmd->sc_data_direction = DMA_TO_DEVICE; | |
1256 | else | |
1257 | cmd->sc_data_direction = DMA_FROM_DEVICE; | |
1258 | ||
aebf526b CH |
1259 | if (blk_rq_is_scsi(req)) |
1260 | return scsi_setup_scsi_cmnd(sdev, req); | |
1261 | else | |
6af7a4ff | 1262 | return scsi_setup_fs_cmnd(sdev, req); |
6af7a4ff CH |
1263 | } |
1264 | ||
a1b73fc1 CH |
1265 | static int |
1266 | scsi_prep_state_check(struct scsi_device *sdev, struct request *req) | |
3b003157 | 1267 | { |
3b003157 CH |
1268 | int ret = BLKPREP_OK; |
1269 | ||
1da177e4 | 1270 | /* |
3b003157 CH |
1271 | * If the device is not in running state we will reject some |
1272 | * or all commands. | |
1da177e4 | 1273 | */ |
3b003157 CH |
1274 | if (unlikely(sdev->sdev_state != SDEV_RUNNING)) { |
1275 | switch (sdev->sdev_state) { | |
1276 | case SDEV_OFFLINE: | |
1b8d2620 | 1277 | case SDEV_TRANSPORT_OFFLINE: |
3b003157 CH |
1278 | /* |
1279 | * If the device is offline we refuse to process any | |
1280 | * commands. The device must be brought online | |
1281 | * before trying any recovery commands. | |
1282 | */ | |
1283 | sdev_printk(KERN_ERR, sdev, | |
1284 | "rejecting I/O to offline device\n"); | |
1285 | ret = BLKPREP_KILL; | |
1286 | break; | |
1287 | case SDEV_DEL: | |
1288 | /* | |
1289 | * If the device is fully deleted, we refuse to | |
1290 | * process any commands as well. | |
1291 | */ | |
9ccfc756 | 1292 | sdev_printk(KERN_ERR, sdev, |
3b003157 CH |
1293 | "rejecting I/O to dead device\n"); |
1294 | ret = BLKPREP_KILL; | |
1295 | break; | |
3b003157 | 1296 | case SDEV_BLOCK: |
6f4267e3 | 1297 | case SDEV_CREATED_BLOCK: |
bba0bdd7 BVA |
1298 | ret = BLKPREP_DEFER; |
1299 | break; | |
1300 | case SDEV_QUIESCE: | |
3b003157 CH |
1301 | /* |
1302 | * If the devices is blocked we defer normal commands. | |
1303 | */ | |
aeec7762 | 1304 | if (req && !(req->rq_flags & RQF_PREEMPT)) |
3b003157 CH |
1305 | ret = BLKPREP_DEFER; |
1306 | break; | |
1307 | default: | |
1308 | /* | |
1309 | * For any other not fully online state we only allow | |
1310 | * special commands. In particular any user initiated | |
1311 | * command is not allowed. | |
1312 | */ | |
aeec7762 | 1313 | if (req && !(req->rq_flags & RQF_PREEMPT)) |
3b003157 CH |
1314 | ret = BLKPREP_KILL; |
1315 | break; | |
1da177e4 | 1316 | } |
1da177e4 | 1317 | } |
7f9a6bc4 JB |
1318 | return ret; |
1319 | } | |
1da177e4 | 1320 | |
a1b73fc1 CH |
1321 | static int |
1322 | scsi_prep_return(struct request_queue *q, struct request *req, int ret) | |
7f9a6bc4 JB |
1323 | { |
1324 | struct scsi_device *sdev = q->queuedata; | |
1da177e4 | 1325 | |
3b003157 CH |
1326 | switch (ret) { |
1327 | case BLKPREP_KILL: | |
e1cd3911 | 1328 | case BLKPREP_INVALID: |
17d5363b | 1329 | scsi_req(req)->result = DID_NO_CONNECT << 16; |
7f9a6bc4 JB |
1330 | /* release the command and kill it */ |
1331 | if (req->special) { | |
1332 | struct scsi_cmnd *cmd = req->special; | |
1333 | scsi_release_buffers(cmd); | |
1334 | scsi_put_command(cmd); | |
68c03d91 | 1335 | put_device(&sdev->sdev_gendev); |
7f9a6bc4 JB |
1336 | req->special = NULL; |
1337 | } | |
3b003157 CH |
1338 | break; |
1339 | case BLKPREP_DEFER: | |
1da177e4 | 1340 | /* |
9934c8c0 | 1341 | * If we defer, the blk_peek_request() returns NULL, but the |
a488e749 JA |
1342 | * queue must be restarted, so we schedule a callback to happen |
1343 | * shortly. | |
1da177e4 | 1344 | */ |
71e75c97 | 1345 | if (atomic_read(&sdev->device_busy) == 0) |
a488e749 | 1346 | blk_delay_queue(q, SCSI_QUEUE_DELAY); |
3b003157 CH |
1347 | break; |
1348 | default: | |
e8064021 | 1349 | req->rq_flags |= RQF_DONTPREP; |
1da177e4 LT |
1350 | } |
1351 | ||
3b003157 | 1352 | return ret; |
1da177e4 | 1353 | } |
7f9a6bc4 | 1354 | |
a1b73fc1 | 1355 | static int scsi_prep_fn(struct request_queue *q, struct request *req) |
7f9a6bc4 JB |
1356 | { |
1357 | struct scsi_device *sdev = q->queuedata; | |
e9c787e6 | 1358 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
a1b73fc1 CH |
1359 | int ret; |
1360 | ||
1361 | ret = scsi_prep_state_check(sdev, req); | |
1362 | if (ret != BLKPREP_OK) | |
1363 | goto out; | |
1364 | ||
e9c787e6 CH |
1365 | if (!req->special) { |
1366 | /* Bail if we can't get a reference to the device */ | |
1367 | if (unlikely(!get_device(&sdev->sdev_gendev))) { | |
1368 | ret = BLKPREP_DEFER; | |
1369 | goto out; | |
1370 | } | |
1371 | ||
1372 | scsi_init_command(sdev, cmd); | |
1373 | req->special = cmd; | |
a1b73fc1 | 1374 | } |
7f9a6bc4 | 1375 | |
e9c787e6 CH |
1376 | cmd->tag = req->tag; |
1377 | cmd->request = req; | |
e9c787e6 CH |
1378 | cmd->prot_op = SCSI_PROT_NORMAL; |
1379 | ||
6af7a4ff | 1380 | ret = scsi_setup_cmnd(sdev, req); |
a1b73fc1 | 1381 | out: |
7f9a6bc4 JB |
1382 | return scsi_prep_return(q, req, ret); |
1383 | } | |
a1b73fc1 CH |
1384 | |
1385 | static void scsi_unprep_fn(struct request_queue *q, struct request *req) | |
1386 | { | |
bed2213d | 1387 | scsi_uninit_cmd(blk_mq_rq_to_pdu(req)); |
a1b73fc1 | 1388 | } |
1da177e4 LT |
1389 | |
1390 | /* | |
1391 | * scsi_dev_queue_ready: if we can send requests to sdev, return 1 else | |
1392 | * return 0. | |
1393 | * | |
1394 | * Called with the queue_lock held. | |
1395 | */ | |
1396 | static inline int scsi_dev_queue_ready(struct request_queue *q, | |
1397 | struct scsi_device *sdev) | |
1398 | { | |
71e75c97 CH |
1399 | unsigned int busy; |
1400 | ||
1401 | busy = atomic_inc_return(&sdev->device_busy) - 1; | |
cd9070c9 | 1402 | if (atomic_read(&sdev->device_blocked)) { |
71e75c97 CH |
1403 | if (busy) |
1404 | goto out_dec; | |
1405 | ||
1da177e4 LT |
1406 | /* |
1407 | * unblock after device_blocked iterates to zero | |
1408 | */ | |
cd9070c9 | 1409 | if (atomic_dec_return(&sdev->device_blocked) > 0) { |
d285203c CH |
1410 | /* |
1411 | * For the MQ case we take care of this in the caller. | |
1412 | */ | |
1413 | if (!q->mq_ops) | |
1414 | blk_delay_queue(q, SCSI_QUEUE_DELAY); | |
71e75c97 | 1415 | goto out_dec; |
1da177e4 | 1416 | } |
71e75c97 CH |
1417 | SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev, |
1418 | "unblocking device at zero depth\n")); | |
1da177e4 | 1419 | } |
71e75c97 CH |
1420 | |
1421 | if (busy >= sdev->queue_depth) | |
1422 | goto out_dec; | |
1da177e4 LT |
1423 | |
1424 | return 1; | |
71e75c97 CH |
1425 | out_dec: |
1426 | atomic_dec(&sdev->device_busy); | |
1427 | return 0; | |
1da177e4 LT |
1428 | } |
1429 | ||
f0c0a376 MC |
1430 | /* |
1431 | * scsi_target_queue_ready: checks if there we can send commands to target | |
1432 | * @sdev: scsi device on starget to check. | |
f0c0a376 MC |
1433 | */ |
1434 | static inline int scsi_target_queue_ready(struct Scsi_Host *shost, | |
1435 | struct scsi_device *sdev) | |
1436 | { | |
1437 | struct scsi_target *starget = scsi_target(sdev); | |
7ae65c0f | 1438 | unsigned int busy; |
f0c0a376 MC |
1439 | |
1440 | if (starget->single_lun) { | |
7ae65c0f | 1441 | spin_lock_irq(shost->host_lock); |
f0c0a376 | 1442 | if (starget->starget_sdev_user && |
7ae65c0f CH |
1443 | starget->starget_sdev_user != sdev) { |
1444 | spin_unlock_irq(shost->host_lock); | |
1445 | return 0; | |
1446 | } | |
f0c0a376 | 1447 | starget->starget_sdev_user = sdev; |
7ae65c0f | 1448 | spin_unlock_irq(shost->host_lock); |
f0c0a376 MC |
1449 | } |
1450 | ||
2ccbb008 CH |
1451 | if (starget->can_queue <= 0) |
1452 | return 1; | |
1453 | ||
7ae65c0f | 1454 | busy = atomic_inc_return(&starget->target_busy) - 1; |
cd9070c9 | 1455 | if (atomic_read(&starget->target_blocked) > 0) { |
7ae65c0f CH |
1456 | if (busy) |
1457 | goto starved; | |
1458 | ||
f0c0a376 MC |
1459 | /* |
1460 | * unblock after target_blocked iterates to zero | |
1461 | */ | |
cd9070c9 | 1462 | if (atomic_dec_return(&starget->target_blocked) > 0) |
7ae65c0f | 1463 | goto out_dec; |
cf68d334 CH |
1464 | |
1465 | SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget, | |
1466 | "unblocking target at zero depth\n")); | |
f0c0a376 MC |
1467 | } |
1468 | ||
2ccbb008 | 1469 | if (busy >= starget->can_queue) |
7ae65c0f | 1470 | goto starved; |
f0c0a376 | 1471 | |
7ae65c0f CH |
1472 | return 1; |
1473 | ||
1474 | starved: | |
1475 | spin_lock_irq(shost->host_lock); | |
1476 | list_move_tail(&sdev->starved_entry, &shost->starved_list); | |
cf68d334 | 1477 | spin_unlock_irq(shost->host_lock); |
7ae65c0f | 1478 | out_dec: |
2ccbb008 CH |
1479 | if (starget->can_queue > 0) |
1480 | atomic_dec(&starget->target_busy); | |
7ae65c0f | 1481 | return 0; |
f0c0a376 MC |
1482 | } |
1483 | ||
1da177e4 LT |
1484 | /* |
1485 | * scsi_host_queue_ready: if we can send requests to shost, return 1 else | |
1486 | * return 0. We must end up running the queue again whenever 0 is | |
1487 | * returned, else IO can hang. | |
1da177e4 LT |
1488 | */ |
1489 | static inline int scsi_host_queue_ready(struct request_queue *q, | |
1490 | struct Scsi_Host *shost, | |
1491 | struct scsi_device *sdev) | |
1492 | { | |
74665016 | 1493 | unsigned int busy; |
cf68d334 | 1494 | |
939647ee | 1495 | if (scsi_host_in_recovery(shost)) |
74665016 CH |
1496 | return 0; |
1497 | ||
1498 | busy = atomic_inc_return(&shost->host_busy) - 1; | |
cd9070c9 | 1499 | if (atomic_read(&shost->host_blocked) > 0) { |
74665016 CH |
1500 | if (busy) |
1501 | goto starved; | |
1502 | ||
1da177e4 LT |
1503 | /* |
1504 | * unblock after host_blocked iterates to zero | |
1505 | */ | |
cd9070c9 | 1506 | if (atomic_dec_return(&shost->host_blocked) > 0) |
74665016 | 1507 | goto out_dec; |
cf68d334 CH |
1508 | |
1509 | SCSI_LOG_MLQUEUE(3, | |
1510 | shost_printk(KERN_INFO, shost, | |
1511 | "unblocking host at zero depth\n")); | |
1da177e4 | 1512 | } |
74665016 CH |
1513 | |
1514 | if (shost->can_queue > 0 && busy >= shost->can_queue) | |
1515 | goto starved; | |
1516 | if (shost->host_self_blocked) | |
1517 | goto starved; | |
1da177e4 LT |
1518 | |
1519 | /* We're OK to process the command, so we can't be starved */ | |
74665016 CH |
1520 | if (!list_empty(&sdev->starved_entry)) { |
1521 | spin_lock_irq(shost->host_lock); | |
1522 | if (!list_empty(&sdev->starved_entry)) | |
1523 | list_del_init(&sdev->starved_entry); | |
1524 | spin_unlock_irq(shost->host_lock); | |
1525 | } | |
1da177e4 | 1526 | |
74665016 CH |
1527 | return 1; |
1528 | ||
1529 | starved: | |
1530 | spin_lock_irq(shost->host_lock); | |
1531 | if (list_empty(&sdev->starved_entry)) | |
1532 | list_add_tail(&sdev->starved_entry, &shost->starved_list); | |
cf68d334 | 1533 | spin_unlock_irq(shost->host_lock); |
74665016 CH |
1534 | out_dec: |
1535 | atomic_dec(&shost->host_busy); | |
1536 | return 0; | |
1da177e4 LT |
1537 | } |
1538 | ||
6c5121b7 KU |
1539 | /* |
1540 | * Busy state exporting function for request stacking drivers. | |
1541 | * | |
1542 | * For efficiency, no lock is taken to check the busy state of | |
1543 | * shost/starget/sdev, since the returned value is not guaranteed and | |
1544 | * may be changed after request stacking drivers call the function, | |
1545 | * regardless of taking lock or not. | |
1546 | * | |
67bd9413 BVA |
1547 | * When scsi can't dispatch I/Os anymore and needs to kill I/Os scsi |
1548 | * needs to return 'not busy'. Otherwise, request stacking drivers | |
1549 | * may hold requests forever. | |
6c5121b7 KU |
1550 | */ |
1551 | static int scsi_lld_busy(struct request_queue *q) | |
1552 | { | |
1553 | struct scsi_device *sdev = q->queuedata; | |
1554 | struct Scsi_Host *shost; | |
6c5121b7 | 1555 | |
3f3299d5 | 1556 | if (blk_queue_dying(q)) |
6c5121b7 KU |
1557 | return 0; |
1558 | ||
1559 | shost = sdev->host; | |
6c5121b7 | 1560 | |
b7e94a16 JN |
1561 | /* |
1562 | * Ignore host/starget busy state. | |
1563 | * Since block layer does not have a concept of fairness across | |
1564 | * multiple queues, congestion of host/starget needs to be handled | |
1565 | * in SCSI layer. | |
1566 | */ | |
1567 | if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev)) | |
6c5121b7 KU |
1568 | return 1; |
1569 | ||
1570 | return 0; | |
1571 | } | |
1572 | ||
1da177e4 | 1573 | /* |
e91442b6 | 1574 | * Kill a request for a dead device |
1da177e4 | 1575 | */ |
165125e1 | 1576 | static void scsi_kill_request(struct request *req, struct request_queue *q) |
1da177e4 | 1577 | { |
bed2213d | 1578 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
03b14708 JS |
1579 | struct scsi_device *sdev; |
1580 | struct scsi_target *starget; | |
1581 | struct Scsi_Host *shost; | |
1da177e4 | 1582 | |
9934c8c0 | 1583 | blk_start_request(req); |
788ce43a | 1584 | |
74571813 HR |
1585 | scmd_printk(KERN_INFO, cmd, "killing request\n"); |
1586 | ||
03b14708 JS |
1587 | sdev = cmd->device; |
1588 | starget = scsi_target(sdev); | |
1589 | shost = sdev->host; | |
e91442b6 JB |
1590 | scsi_init_cmd_errh(cmd); |
1591 | cmd->result = DID_NO_CONNECT << 16; | |
1592 | atomic_inc(&cmd->device->iorequest_cnt); | |
e36e0c80 TH |
1593 | |
1594 | /* | |
1595 | * SCSI request completion path will do scsi_device_unbusy(), | |
1596 | * bump busy counts. To bump the counters, we need to dance | |
1597 | * with the locks as normal issue path does. | |
1598 | */ | |
71e75c97 | 1599 | atomic_inc(&sdev->device_busy); |
74665016 | 1600 | atomic_inc(&shost->host_busy); |
2ccbb008 CH |
1601 | if (starget->can_queue > 0) |
1602 | atomic_inc(&starget->target_busy); | |
e36e0c80 | 1603 | |
242f9dcb | 1604 | blk_complete_request(req); |
1da177e4 LT |
1605 | } |
1606 | ||
1aea6434 JA |
1607 | static void scsi_softirq_done(struct request *rq) |
1608 | { | |
bed2213d | 1609 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
242f9dcb | 1610 | unsigned long wait_for = (cmd->allowed + 1) * rq->timeout; |
1aea6434 JA |
1611 | int disposition; |
1612 | ||
1613 | INIT_LIST_HEAD(&cmd->eh_entry); | |
1614 | ||
242f9dcb JA |
1615 | atomic_inc(&cmd->device->iodone_cnt); |
1616 | if (cmd->result) | |
1617 | atomic_inc(&cmd->device->ioerr_cnt); | |
1618 | ||
1aea6434 JA |
1619 | disposition = scsi_decide_disposition(cmd); |
1620 | if (disposition != SUCCESS && | |
1621 | time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) { | |
1622 | sdev_printk(KERN_ERR, cmd->device, | |
1623 | "timing out command, waited %lus\n", | |
1624 | wait_for/HZ); | |
1625 | disposition = SUCCESS; | |
1626 | } | |
91921e01 | 1627 | |
1aea6434 JA |
1628 | scsi_log_completion(cmd, disposition); |
1629 | ||
1630 | switch (disposition) { | |
1631 | case SUCCESS: | |
1632 | scsi_finish_command(cmd); | |
1633 | break; | |
1634 | case NEEDS_RETRY: | |
596f482a | 1635 | scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY); |
1aea6434 JA |
1636 | break; |
1637 | case ADD_TO_MLQUEUE: | |
1638 | scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); | |
1639 | break; | |
1640 | default: | |
a0658632 | 1641 | scsi_eh_scmd_add(cmd); |
2171b6d0 | 1642 | break; |
1aea6434 JA |
1643 | } |
1644 | } | |
1645 | ||
82042a2c CH |
1646 | /** |
1647 | * scsi_dispatch_command - Dispatch a command to the low-level driver. | |
1648 | * @cmd: command block we are dispatching. | |
1649 | * | |
1650 | * Return: nonzero return request was rejected and device's queue needs to be | |
1651 | * plugged. | |
1652 | */ | |
1653 | static int scsi_dispatch_cmd(struct scsi_cmnd *cmd) | |
1654 | { | |
1655 | struct Scsi_Host *host = cmd->device->host; | |
1656 | int rtn = 0; | |
1657 | ||
1658 | atomic_inc(&cmd->device->iorequest_cnt); | |
1659 | ||
1660 | /* check if the device is still usable */ | |
1661 | if (unlikely(cmd->device->sdev_state == SDEV_DEL)) { | |
1662 | /* in SDEV_DEL we error all commands. DID_NO_CONNECT | |
1663 | * returns an immediate error upwards, and signals | |
1664 | * that the device is no longer present */ | |
1665 | cmd->result = DID_NO_CONNECT << 16; | |
1666 | goto done; | |
1667 | } | |
1668 | ||
1669 | /* Check to see if the scsi lld made this device blocked. */ | |
1670 | if (unlikely(scsi_device_blocked(cmd->device))) { | |
1671 | /* | |
1672 | * in blocked state, the command is just put back on | |
1673 | * the device queue. The suspend state has already | |
1674 | * blocked the queue so future requests should not | |
1675 | * occur until the device transitions out of the | |
1676 | * suspend state. | |
1677 | */ | |
1678 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd, | |
1679 | "queuecommand : device blocked\n")); | |
1680 | return SCSI_MLQUEUE_DEVICE_BUSY; | |
1681 | } | |
1682 | ||
1683 | /* Store the LUN value in cmnd, if needed. */ | |
1684 | if (cmd->device->lun_in_cdb) | |
1685 | cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) | | |
1686 | (cmd->device->lun << 5 & 0xe0); | |
1687 | ||
1688 | scsi_log_send(cmd); | |
1689 | ||
1690 | /* | |
1691 | * Before we queue this command, check if the command | |
1692 | * length exceeds what the host adapter can handle. | |
1693 | */ | |
1694 | if (cmd->cmd_len > cmd->device->host->max_cmd_len) { | |
1695 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd, | |
1696 | "queuecommand : command too long. " | |
1697 | "cdb_size=%d host->max_cmd_len=%d\n", | |
1698 | cmd->cmd_len, cmd->device->host->max_cmd_len)); | |
1699 | cmd->result = (DID_ABORT << 16); | |
1700 | goto done; | |
1701 | } | |
1702 | ||
1703 | if (unlikely(host->shost_state == SHOST_DEL)) { | |
1704 | cmd->result = (DID_NO_CONNECT << 16); | |
1705 | goto done; | |
1706 | ||
1707 | } | |
1708 | ||
1709 | trace_scsi_dispatch_cmd_start(cmd); | |
1710 | rtn = host->hostt->queuecommand(host, cmd); | |
1711 | if (rtn) { | |
1712 | trace_scsi_dispatch_cmd_error(cmd, rtn); | |
1713 | if (rtn != SCSI_MLQUEUE_DEVICE_BUSY && | |
1714 | rtn != SCSI_MLQUEUE_TARGET_BUSY) | |
1715 | rtn = SCSI_MLQUEUE_HOST_BUSY; | |
1716 | ||
1717 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd, | |
1718 | "queuecommand : request rejected\n")); | |
1719 | } | |
1720 | ||
1721 | return rtn; | |
1722 | done: | |
1723 | cmd->scsi_done(cmd); | |
1724 | return 0; | |
1725 | } | |
1726 | ||
3b5382c4 CH |
1727 | /** |
1728 | * scsi_done - Invoke completion on finished SCSI command. | |
1729 | * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives | |
1730 | * ownership back to SCSI Core -- i.e. the LLDD has finished with it. | |
1731 | * | |
1732 | * Description: This function is the mid-level's (SCSI Core) interrupt routine, | |
1733 | * which regains ownership of the SCSI command (de facto) from a LLDD, and | |
1734 | * calls blk_complete_request() for further processing. | |
1735 | * | |
1736 | * This function is interrupt context safe. | |
1737 | */ | |
1738 | static void scsi_done(struct scsi_cmnd *cmd) | |
1739 | { | |
1740 | trace_scsi_dispatch_cmd_done(cmd); | |
1741 | blk_complete_request(cmd->request); | |
1742 | } | |
1743 | ||
1da177e4 LT |
1744 | /* |
1745 | * Function: scsi_request_fn() | |
1746 | * | |
1747 | * Purpose: Main strategy routine for SCSI. | |
1748 | * | |
1749 | * Arguments: q - Pointer to actual queue. | |
1750 | * | |
1751 | * Returns: Nothing | |
1752 | * | |
e98f42bc DLM |
1753 | * Lock status: request queue lock assumed to be held when called. |
1754 | * | |
1755 | * Note: See sd_zbc.c sd_zbc_write_lock_zone() for write order | |
1756 | * protection for ZBC disks. | |
1da177e4 LT |
1757 | */ |
1758 | static void scsi_request_fn(struct request_queue *q) | |
613be1f6 BVA |
1759 | __releases(q->queue_lock) |
1760 | __acquires(q->queue_lock) | |
1da177e4 LT |
1761 | { |
1762 | struct scsi_device *sdev = q->queuedata; | |
1763 | struct Scsi_Host *shost; | |
1764 | struct scsi_cmnd *cmd; | |
1765 | struct request *req; | |
1766 | ||
1da177e4 LT |
1767 | /* |
1768 | * To start with, we keep looping until the queue is empty, or until | |
1769 | * the host is no longer able to accept any more requests. | |
1770 | */ | |
1771 | shost = sdev->host; | |
a488e749 | 1772 | for (;;) { |
1da177e4 LT |
1773 | int rtn; |
1774 | /* | |
1775 | * get next queueable request. We do this early to make sure | |
91921e01 | 1776 | * that the request is fully prepared even if we cannot |
1da177e4 LT |
1777 | * accept it. |
1778 | */ | |
9934c8c0 | 1779 | req = blk_peek_request(q); |
71e75c97 | 1780 | if (!req) |
1da177e4 LT |
1781 | break; |
1782 | ||
1783 | if (unlikely(!scsi_device_online(sdev))) { | |
9ccfc756 JB |
1784 | sdev_printk(KERN_ERR, sdev, |
1785 | "rejecting I/O to offline device\n"); | |
e91442b6 | 1786 | scsi_kill_request(req, q); |
1da177e4 LT |
1787 | continue; |
1788 | } | |
1789 | ||
71e75c97 CH |
1790 | if (!scsi_dev_queue_ready(q, sdev)) |
1791 | break; | |
1da177e4 LT |
1792 | |
1793 | /* | |
1794 | * Remove the request from the request list. | |
1795 | */ | |
1796 | if (!(blk_queue_tagged(q) && !blk_queue_start_tag(q, req))) | |
9934c8c0 | 1797 | blk_start_request(req); |
1da177e4 | 1798 | |
cf68d334 | 1799 | spin_unlock_irq(q->queue_lock); |
bed2213d BVA |
1800 | cmd = blk_mq_rq_to_pdu(req); |
1801 | if (cmd != req->special) { | |
e91442b6 JB |
1802 | printk(KERN_CRIT "impossible request in %s.\n" |
1803 | "please mail a stack trace to " | |
4aff5e23 | 1804 | "linux-scsi@vger.kernel.org\n", |
cadbd4a5 | 1805 | __func__); |
4aff5e23 | 1806 | blk_dump_rq_flags(req, "foo"); |
e91442b6 JB |
1807 | BUG(); |
1808 | } | |
1da177e4 | 1809 | |
ecefe8a9 MC |
1810 | /* |
1811 | * We hit this when the driver is using a host wide | |
1812 | * tag map. For device level tag maps the queue_depth check | |
1813 | * in the device ready fn would prevent us from trying | |
1814 | * to allocate a tag. Since the map is a shared host resource | |
1815 | * we add the dev to the starved list so it eventually gets | |
1816 | * a run when a tag is freed. | |
1817 | */ | |
e8064021 | 1818 | if (blk_queue_tagged(q) && !(req->rq_flags & RQF_QUEUED)) { |
cf68d334 | 1819 | spin_lock_irq(shost->host_lock); |
ecefe8a9 MC |
1820 | if (list_empty(&sdev->starved_entry)) |
1821 | list_add_tail(&sdev->starved_entry, | |
1822 | &shost->starved_list); | |
cf68d334 | 1823 | spin_unlock_irq(shost->host_lock); |
ecefe8a9 MC |
1824 | goto not_ready; |
1825 | } | |
1826 | ||
f0c0a376 MC |
1827 | if (!scsi_target_queue_ready(shost, sdev)) |
1828 | goto not_ready; | |
1829 | ||
1da177e4 | 1830 | if (!scsi_host_queue_ready(q, shost, sdev)) |
cf68d334 | 1831 | goto host_not_ready; |
125c99bc CH |
1832 | |
1833 | if (sdev->simple_tags) | |
1834 | cmd->flags |= SCMD_TAGGED; | |
1835 | else | |
1836 | cmd->flags &= ~SCMD_TAGGED; | |
1da177e4 | 1837 | |
1da177e4 LT |
1838 | /* |
1839 | * Finally, initialize any error handling parameters, and set up | |
1840 | * the timers for timeouts. | |
1841 | */ | |
1842 | scsi_init_cmd_errh(cmd); | |
1843 | ||
1844 | /* | |
1845 | * Dispatch the command to the low-level driver. | |
1846 | */ | |
3b5382c4 | 1847 | cmd->scsi_done = scsi_done; |
1da177e4 | 1848 | rtn = scsi_dispatch_cmd(cmd); |
d0d3bbf9 CH |
1849 | if (rtn) { |
1850 | scsi_queue_insert(cmd, rtn); | |
1851 | spin_lock_irq(q->queue_lock); | |
a488e749 | 1852 | goto out_delay; |
d0d3bbf9 CH |
1853 | } |
1854 | spin_lock_irq(q->queue_lock); | |
1da177e4 LT |
1855 | } |
1856 | ||
613be1f6 | 1857 | return; |
1da177e4 | 1858 | |
cf68d334 | 1859 | host_not_ready: |
2ccbb008 CH |
1860 | if (scsi_target(sdev)->can_queue > 0) |
1861 | atomic_dec(&scsi_target(sdev)->target_busy); | |
cf68d334 | 1862 | not_ready: |
1da177e4 LT |
1863 | /* |
1864 | * lock q, handle tag, requeue req, and decrement device_busy. We | |
1865 | * must return with queue_lock held. | |
1866 | * | |
1867 | * Decrementing device_busy without checking it is OK, as all such | |
1868 | * cases (host limits or settings) should run the queue at some | |
1869 | * later time. | |
1870 | */ | |
1871 | spin_lock_irq(q->queue_lock); | |
1872 | blk_requeue_request(q, req); | |
71e75c97 | 1873 | atomic_dec(&sdev->device_busy); |
a488e749 | 1874 | out_delay: |
480cadc2 | 1875 | if (!atomic_read(&sdev->device_busy) && !scsi_device_blocked(sdev)) |
a488e749 | 1876 | blk_delay_queue(q, SCSI_QUEUE_DELAY); |
1da177e4 LT |
1877 | } |
1878 | ||
fc17b653 | 1879 | static inline blk_status_t prep_to_mq(int ret) |
d285203c CH |
1880 | { |
1881 | switch (ret) { | |
1882 | case BLKPREP_OK: | |
fc17b653 | 1883 | return BLK_STS_OK; |
d285203c | 1884 | case BLKPREP_DEFER: |
fc17b653 | 1885 | return BLK_STS_RESOURCE; |
d285203c | 1886 | default: |
fc17b653 | 1887 | return BLK_STS_IOERR; |
d285203c CH |
1888 | } |
1889 | } | |
1890 | ||
be4c186c BVA |
1891 | /* Size in bytes of the sg-list stored in the scsi-mq command-private data. */ |
1892 | static unsigned int scsi_mq_sgl_size(struct Scsi_Host *shost) | |
1893 | { | |
1894 | return min_t(unsigned int, shost->sg_tablesize, SG_CHUNK_SIZE) * | |
1895 | sizeof(struct scatterlist); | |
1896 | } | |
1897 | ||
d285203c CH |
1898 | static int scsi_mq_prep_fn(struct request *req) |
1899 | { | |
1900 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); | |
1901 | struct scsi_device *sdev = req->q->queuedata; | |
1902 | struct Scsi_Host *shost = sdev->host; | |
d285203c CH |
1903 | struct scatterlist *sg; |
1904 | ||
08f78436 | 1905 | scsi_init_command(sdev, cmd); |
d285203c CH |
1906 | |
1907 | req->special = cmd; | |
1908 | ||
1909 | cmd->request = req; | |
d285203c CH |
1910 | |
1911 | cmd->tag = req->tag; | |
d285203c CH |
1912 | cmd->prot_op = SCSI_PROT_NORMAL; |
1913 | ||
d285203c CH |
1914 | sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size; |
1915 | cmd->sdb.table.sgl = sg; | |
1916 | ||
1917 | if (scsi_host_get_prot(shost)) { | |
d285203c CH |
1918 | memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer)); |
1919 | ||
1920 | cmd->prot_sdb->table.sgl = | |
1921 | (struct scatterlist *)(cmd->prot_sdb + 1); | |
1922 | } | |
1923 | ||
1924 | if (blk_bidi_rq(req)) { | |
1925 | struct request *next_rq = req->next_rq; | |
1926 | struct scsi_data_buffer *bidi_sdb = blk_mq_rq_to_pdu(next_rq); | |
1927 | ||
1928 | memset(bidi_sdb, 0, sizeof(struct scsi_data_buffer)); | |
1929 | bidi_sdb->table.sgl = | |
1930 | (struct scatterlist *)(bidi_sdb + 1); | |
1931 | ||
1932 | next_rq->special = bidi_sdb; | |
1933 | } | |
1934 | ||
fe052529 CH |
1935 | blk_mq_start_request(req); |
1936 | ||
8fe8ffb1 | 1937 | return scsi_setup_cmnd(sdev, req); |
d285203c CH |
1938 | } |
1939 | ||
1940 | static void scsi_mq_done(struct scsi_cmnd *cmd) | |
1941 | { | |
1942 | trace_scsi_dispatch_cmd_done(cmd); | |
08e0029a | 1943 | blk_mq_complete_request(cmd->request); |
d285203c CH |
1944 | } |
1945 | ||
0df21c86 | 1946 | static void scsi_mq_put_budget(struct blk_mq_hw_ctx *hctx) |
d285203c | 1947 | { |
0df21c86 ML |
1948 | struct request_queue *q = hctx->queue; |
1949 | struct scsi_device *sdev = q->queuedata; | |
0df21c86 | 1950 | |
0df21c86 ML |
1951 | atomic_dec(&sdev->device_busy); |
1952 | put_device(&sdev->sdev_gendev); | |
1953 | } | |
1954 | ||
88022d72 | 1955 | static bool scsi_mq_get_budget(struct blk_mq_hw_ctx *hctx) |
0df21c86 ML |
1956 | { |
1957 | struct request_queue *q = hctx->queue; | |
d285203c | 1958 | struct scsi_device *sdev = q->queuedata; |
d285203c | 1959 | |
d285203c CH |
1960 | if (!get_device(&sdev->sdev_gendev)) |
1961 | goto out; | |
d285203c CH |
1962 | if (!scsi_dev_queue_ready(q, sdev)) |
1963 | goto out_put_device; | |
d285203c | 1964 | |
88022d72 | 1965 | return true; |
0df21c86 | 1966 | |
0df21c86 ML |
1967 | out_put_device: |
1968 | put_device(&sdev->sdev_gendev); | |
1969 | out: | |
7e70aa78 ML |
1970 | if (atomic_read(&sdev->device_busy) == 0 && !scsi_device_blocked(sdev)) |
1971 | blk_mq_delay_run_hw_queue(hctx, SCSI_QUEUE_DELAY); | |
88022d72 | 1972 | return false; |
0df21c86 ML |
1973 | } |
1974 | ||
fc17b653 | 1975 | static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, |
74c45052 | 1976 | const struct blk_mq_queue_data *bd) |
d285203c | 1977 | { |
74c45052 | 1978 | struct request *req = bd->rq; |
d285203c CH |
1979 | struct request_queue *q = req->q; |
1980 | struct scsi_device *sdev = q->queuedata; | |
1981 | struct Scsi_Host *shost = sdev->host; | |
1982 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); | |
fc17b653 | 1983 | blk_status_t ret; |
d285203c CH |
1984 | int reason; |
1985 | ||
1986 | ret = prep_to_mq(scsi_prep_state_check(sdev, req)); | |
fc17b653 | 1987 | if (ret != BLK_STS_OK) |
0df21c86 | 1988 | goto out_put_budget; |
d285203c | 1989 | |
fc17b653 | 1990 | ret = BLK_STS_RESOURCE; |
d285203c | 1991 | if (!scsi_target_queue_ready(shost, sdev)) |
826a70a0 | 1992 | goto out_put_budget; |
d285203c CH |
1993 | if (!scsi_host_queue_ready(q, shost, sdev)) |
1994 | goto out_dec_target_busy; | |
1995 | ||
e8064021 | 1996 | if (!(req->rq_flags & RQF_DONTPREP)) { |
d285203c | 1997 | ret = prep_to_mq(scsi_mq_prep_fn(req)); |
fc17b653 | 1998 | if (ret != BLK_STS_OK) |
d285203c | 1999 | goto out_dec_host_busy; |
e8064021 | 2000 | req->rq_flags |= RQF_DONTPREP; |
fe052529 CH |
2001 | } else { |
2002 | blk_mq_start_request(req); | |
d285203c CH |
2003 | } |
2004 | ||
125c99bc CH |
2005 | if (sdev->simple_tags) |
2006 | cmd->flags |= SCMD_TAGGED; | |
b1dd2aac | 2007 | else |
125c99bc | 2008 | cmd->flags &= ~SCMD_TAGGED; |
b1dd2aac | 2009 | |
d285203c CH |
2010 | scsi_init_cmd_errh(cmd); |
2011 | cmd->scsi_done = scsi_mq_done; | |
2012 | ||
2013 | reason = scsi_dispatch_cmd(cmd); | |
2014 | if (reason) { | |
2015 | scsi_set_blocked(cmd, reason); | |
fc17b653 | 2016 | ret = BLK_STS_RESOURCE; |
d285203c CH |
2017 | goto out_dec_host_busy; |
2018 | } | |
2019 | ||
fc17b653 | 2020 | return BLK_STS_OK; |
d285203c CH |
2021 | |
2022 | out_dec_host_busy: | |
826a70a0 | 2023 | atomic_dec(&shost->host_busy); |
d285203c CH |
2024 | out_dec_target_busy: |
2025 | if (scsi_target(sdev)->can_queue > 0) | |
2026 | atomic_dec(&scsi_target(sdev)->target_busy); | |
0df21c86 ML |
2027 | out_put_budget: |
2028 | scsi_mq_put_budget(hctx); | |
d285203c | 2029 | switch (ret) { |
fc17b653 CH |
2030 | case BLK_STS_OK: |
2031 | break; | |
2032 | case BLK_STS_RESOURCE: | |
d285203c CH |
2033 | if (atomic_read(&sdev->device_busy) == 0 && |
2034 | !scsi_device_blocked(sdev)) | |
36e3cf27 | 2035 | blk_mq_delay_run_hw_queue(hctx, SCSI_QUEUE_DELAY); |
d285203c | 2036 | break; |
fc17b653 | 2037 | default: |
d285203c CH |
2038 | /* |
2039 | * Make sure to release all allocated ressources when | |
2040 | * we hit an error, as we will never see this command | |
2041 | * again. | |
2042 | */ | |
e8064021 | 2043 | if (req->rq_flags & RQF_DONTPREP) |
d285203c CH |
2044 | scsi_mq_uninit_cmd(cmd); |
2045 | break; | |
d285203c CH |
2046 | } |
2047 | return ret; | |
2048 | } | |
2049 | ||
0152fb6b CH |
2050 | static enum blk_eh_timer_return scsi_timeout(struct request *req, |
2051 | bool reserved) | |
2052 | { | |
2053 | if (reserved) | |
2054 | return BLK_EH_RESET_TIMER; | |
2055 | return scsi_times_out(req); | |
2056 | } | |
2057 | ||
e7008ff5 BVA |
2058 | static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq, |
2059 | unsigned int hctx_idx, unsigned int numa_node) | |
d285203c | 2060 | { |
d6296d39 | 2061 | struct Scsi_Host *shost = set->driver_data; |
8e688254 | 2062 | const bool unchecked_isa_dma = shost->unchecked_isa_dma; |
d285203c | 2063 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
08f78436 | 2064 | struct scatterlist *sg; |
d285203c | 2065 | |
8e688254 BVA |
2066 | if (unchecked_isa_dma) |
2067 | cmd->flags |= SCMD_UNCHECKED_ISA_DMA; | |
2068 | cmd->sense_buffer = scsi_alloc_sense_buffer(unchecked_isa_dma, | |
2069 | GFP_KERNEL, numa_node); | |
d285203c CH |
2070 | if (!cmd->sense_buffer) |
2071 | return -ENOMEM; | |
82ed4db4 | 2072 | cmd->req.sense = cmd->sense_buffer; |
08f78436 BVA |
2073 | |
2074 | if (scsi_host_get_prot(shost)) { | |
2075 | sg = (void *)cmd + sizeof(struct scsi_cmnd) + | |
2076 | shost->hostt->cmd_size; | |
2077 | cmd->prot_sdb = (void *)sg + scsi_mq_sgl_size(shost); | |
2078 | } | |
2079 | ||
d285203c CH |
2080 | return 0; |
2081 | } | |
2082 | ||
e7008ff5 BVA |
2083 | static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq, |
2084 | unsigned int hctx_idx) | |
d285203c CH |
2085 | { |
2086 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); | |
2087 | ||
8e688254 BVA |
2088 | scsi_free_sense_buffer(cmd->flags & SCMD_UNCHECKED_ISA_DMA, |
2089 | cmd->sense_buffer); | |
d285203c CH |
2090 | } |
2091 | ||
2d9c5c20 CH |
2092 | static int scsi_map_queues(struct blk_mq_tag_set *set) |
2093 | { | |
2094 | struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set); | |
2095 | ||
2096 | if (shost->hostt->map_queues) | |
2097 | return shost->hostt->map_queues(shost); | |
2098 | return blk_mq_map_queues(set); | |
2099 | } | |
2100 | ||
f1bea55d | 2101 | static u64 scsi_calculate_bounce_limit(struct Scsi_Host *shost) |
1da177e4 LT |
2102 | { |
2103 | struct device *host_dev; | |
2104 | u64 bounce_limit = 0xffffffff; | |
2105 | ||
2106 | if (shost->unchecked_isa_dma) | |
2107 | return BLK_BOUNCE_ISA; | |
2108 | /* | |
2109 | * Platforms with virtual-DMA translation | |
2110 | * hardware have no practical limit. | |
2111 | */ | |
2112 | if (!PCI_DMA_BUS_IS_PHYS) | |
2113 | return BLK_BOUNCE_ANY; | |
2114 | ||
2115 | host_dev = scsi_get_device(shost); | |
2116 | if (host_dev && host_dev->dma_mask) | |
e83b3664 | 2117 | bounce_limit = (u64)dma_max_pfn(host_dev) << PAGE_SHIFT; |
1da177e4 LT |
2118 | |
2119 | return bounce_limit; | |
2120 | } | |
1da177e4 | 2121 | |
d48777a6 | 2122 | void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) |
1da177e4 | 2123 | { |
6f381fa3 | 2124 | struct device *dev = shost->dma_dev; |
1da177e4 | 2125 | |
9efc160f BVA |
2126 | queue_flag_set_unlocked(QUEUE_FLAG_SCSI_PASSTHROUGH, q); |
2127 | ||
a8474ce2 JA |
2128 | /* |
2129 | * this limit is imposed by hardware restrictions | |
2130 | */ | |
8a78362c | 2131 | blk_queue_max_segments(q, min_t(unsigned short, shost->sg_tablesize, |
65e8617f | 2132 | SG_MAX_SEGMENTS)); |
a8474ce2 | 2133 | |
13f05c8d MP |
2134 | if (scsi_host_prot_dma(shost)) { |
2135 | shost->sg_prot_tablesize = | |
2136 | min_not_zero(shost->sg_prot_tablesize, | |
2137 | (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS); | |
2138 | BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize); | |
2139 | blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize); | |
2140 | } | |
2141 | ||
086fa5ff | 2142 | blk_queue_max_hw_sectors(q, shost->max_sectors); |
1da177e4 LT |
2143 | blk_queue_bounce_limit(q, scsi_calculate_bounce_limit(shost)); |
2144 | blk_queue_segment_boundary(q, shost->dma_boundary); | |
99c84dbd | 2145 | dma_set_seg_boundary(dev, shost->dma_boundary); |
1da177e4 | 2146 | |
860ac568 FT |
2147 | blk_queue_max_segment_size(q, dma_get_max_seg_size(dev)); |
2148 | ||
1da177e4 | 2149 | if (!shost->use_clustering) |
e692cb66 | 2150 | q->limits.cluster = 0; |
465ff318 JB |
2151 | |
2152 | /* | |
90addc6b HC |
2153 | * Set a reasonable default alignment: The larger of 32-byte (dword), |
2154 | * which is a common minimum for HBAs, and the minimum DMA alignment, | |
2155 | * which is set by the platform. | |
2156 | * | |
2157 | * Devices that require a bigger alignment can increase it later. | |
465ff318 | 2158 | */ |
90addc6b | 2159 | blk_queue_dma_alignment(q, max(4, dma_get_cache_alignment()) - 1); |
d285203c | 2160 | } |
d48777a6 | 2161 | EXPORT_SYMBOL_GPL(__scsi_init_queue); |
465ff318 | 2162 | |
e7008ff5 BVA |
2163 | static int scsi_old_init_rq(struct request_queue *q, struct request *rq, |
2164 | gfp_t gfp) | |
d285203c | 2165 | { |
e9c787e6 | 2166 | struct Scsi_Host *shost = q->rq_alloc_data; |
8e688254 | 2167 | const bool unchecked_isa_dma = shost->unchecked_isa_dma; |
e9c787e6 | 2168 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
d285203c | 2169 | |
e9c787e6 CH |
2170 | memset(cmd, 0, sizeof(*cmd)); |
2171 | ||
8e688254 BVA |
2172 | if (unchecked_isa_dma) |
2173 | cmd->flags |= SCMD_UNCHECKED_ISA_DMA; | |
2174 | cmd->sense_buffer = scsi_alloc_sense_buffer(unchecked_isa_dma, gfp, | |
2175 | NUMA_NO_NODE); | |
e9c787e6 CH |
2176 | if (!cmd->sense_buffer) |
2177 | goto fail; | |
82ed4db4 | 2178 | cmd->req.sense = cmd->sense_buffer; |
e9c787e6 CH |
2179 | |
2180 | if (scsi_host_get_prot(shost) >= SHOST_DIX_TYPE0_PROTECTION) { | |
2181 | cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp); | |
2182 | if (!cmd->prot_sdb) | |
2183 | goto fail_free_sense; | |
2184 | } | |
2185 | ||
2186 | return 0; | |
2187 | ||
2188 | fail_free_sense: | |
8e688254 | 2189 | scsi_free_sense_buffer(unchecked_isa_dma, cmd->sense_buffer); |
e9c787e6 CH |
2190 | fail: |
2191 | return -ENOMEM; | |
2192 | } | |
2193 | ||
e7008ff5 | 2194 | static void scsi_old_exit_rq(struct request_queue *q, struct request *rq) |
e9c787e6 | 2195 | { |
e9c787e6 CH |
2196 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
2197 | ||
2198 | if (cmd->prot_sdb) | |
2199 | kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb); | |
8e688254 BVA |
2200 | scsi_free_sense_buffer(cmd->flags & SCMD_UNCHECKED_ISA_DMA, |
2201 | cmd->sense_buffer); | |
1da177e4 | 2202 | } |
b58d9154 | 2203 | |
e7008ff5 | 2204 | struct request_queue *scsi_old_alloc_queue(struct scsi_device *sdev) |
b58d9154 | 2205 | { |
e9c787e6 | 2206 | struct Scsi_Host *shost = sdev->host; |
b58d9154 FT |
2207 | struct request_queue *q; |
2208 | ||
e9c787e6 | 2209 | q = blk_alloc_queue_node(GFP_KERNEL, NUMA_NO_NODE); |
b58d9154 FT |
2210 | if (!q) |
2211 | return NULL; | |
e9c787e6 CH |
2212 | q->cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size; |
2213 | q->rq_alloc_data = shost; | |
2214 | q->request_fn = scsi_request_fn; | |
e7008ff5 BVA |
2215 | q->init_rq_fn = scsi_old_init_rq; |
2216 | q->exit_rq_fn = scsi_old_exit_rq; | |
ca18d6f7 | 2217 | q->initialize_rq_fn = scsi_initialize_rq; |
e9c787e6 CH |
2218 | |
2219 | if (blk_init_allocated_queue(q) < 0) { | |
2220 | blk_cleanup_queue(q); | |
2221 | return NULL; | |
2222 | } | |
b58d9154 | 2223 | |
e9c787e6 | 2224 | __scsi_init_queue(shost, q); |
b58d9154 | 2225 | blk_queue_prep_rq(q, scsi_prep_fn); |
a1b73fc1 | 2226 | blk_queue_unprep_rq(q, scsi_unprep_fn); |
b58d9154 | 2227 | blk_queue_softirq_done(q, scsi_softirq_done); |
242f9dcb | 2228 | blk_queue_rq_timed_out(q, scsi_times_out); |
6c5121b7 | 2229 | blk_queue_lld_busy(q, scsi_lld_busy); |
b58d9154 FT |
2230 | return q; |
2231 | } | |
1da177e4 | 2232 | |
f363b089 | 2233 | static const struct blk_mq_ops scsi_mq_ops = { |
0df21c86 ML |
2234 | .get_budget = scsi_mq_get_budget, |
2235 | .put_budget = scsi_mq_put_budget, | |
d285203c CH |
2236 | .queue_rq = scsi_queue_rq, |
2237 | .complete = scsi_softirq_done, | |
0152fb6b | 2238 | .timeout = scsi_timeout, |
0eebd005 BVA |
2239 | #ifdef CONFIG_BLK_DEBUG_FS |
2240 | .show_rq = scsi_show_rq, | |
2241 | #endif | |
e7008ff5 BVA |
2242 | .init_request = scsi_mq_init_request, |
2243 | .exit_request = scsi_mq_exit_request, | |
ca18d6f7 | 2244 | .initialize_rq_fn = scsi_initialize_rq, |
2d9c5c20 | 2245 | .map_queues = scsi_map_queues, |
d285203c CH |
2246 | }; |
2247 | ||
2248 | struct request_queue *scsi_mq_alloc_queue(struct scsi_device *sdev) | |
2249 | { | |
2250 | sdev->request_queue = blk_mq_init_queue(&sdev->host->tag_set); | |
2251 | if (IS_ERR(sdev->request_queue)) | |
2252 | return NULL; | |
2253 | ||
2254 | sdev->request_queue->queuedata = sdev; | |
2255 | __scsi_init_queue(sdev->host, sdev->request_queue); | |
2256 | return sdev->request_queue; | |
2257 | } | |
2258 | ||
2259 | int scsi_mq_setup_tags(struct Scsi_Host *shost) | |
2260 | { | |
be4c186c | 2261 | unsigned int cmd_size, sgl_size; |
d285203c | 2262 | |
be4c186c | 2263 | sgl_size = scsi_mq_sgl_size(shost); |
d285203c CH |
2264 | cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size; |
2265 | if (scsi_host_get_prot(shost)) | |
2266 | cmd_size += sizeof(struct scsi_data_buffer) + sgl_size; | |
2267 | ||
2268 | memset(&shost->tag_set, 0, sizeof(shost->tag_set)); | |
2269 | shost->tag_set.ops = &scsi_mq_ops; | |
efec4b90 | 2270 | shost->tag_set.nr_hw_queues = shost->nr_hw_queues ? : 1; |
d285203c CH |
2271 | shost->tag_set.queue_depth = shost->can_queue; |
2272 | shost->tag_set.cmd_size = cmd_size; | |
2273 | shost->tag_set.numa_node = NUMA_NO_NODE; | |
2274 | shost->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE; | |
24391c0d SL |
2275 | shost->tag_set.flags |= |
2276 | BLK_ALLOC_POLICY_TO_MQ_FLAG(shost->hostt->tag_alloc_policy); | |
d285203c CH |
2277 | shost->tag_set.driver_data = shost; |
2278 | ||
2279 | return blk_mq_alloc_tag_set(&shost->tag_set); | |
2280 | } | |
2281 | ||
2282 | void scsi_mq_destroy_tags(struct Scsi_Host *shost) | |
2283 | { | |
2284 | blk_mq_free_tag_set(&shost->tag_set); | |
2285 | } | |
2286 | ||
857de6e0 HR |
2287 | /** |
2288 | * scsi_device_from_queue - return sdev associated with a request_queue | |
2289 | * @q: The request queue to return the sdev from | |
2290 | * | |
2291 | * Return the sdev associated with a request queue or NULL if the | |
2292 | * request_queue does not reference a SCSI device. | |
2293 | */ | |
2294 | struct scsi_device *scsi_device_from_queue(struct request_queue *q) | |
2295 | { | |
2296 | struct scsi_device *sdev = NULL; | |
2297 | ||
2298 | if (q->mq_ops) { | |
2299 | if (q->mq_ops == &scsi_mq_ops) | |
2300 | sdev = q->queuedata; | |
2301 | } else if (q->request_fn == scsi_request_fn) | |
2302 | sdev = q->queuedata; | |
2303 | if (!sdev || !get_device(&sdev->sdev_gendev)) | |
2304 | sdev = NULL; | |
2305 | ||
2306 | return sdev; | |
2307 | } | |
2308 | EXPORT_SYMBOL_GPL(scsi_device_from_queue); | |
2309 | ||
1da177e4 LT |
2310 | /* |
2311 | * Function: scsi_block_requests() | |
2312 | * | |
2313 | * Purpose: Utility function used by low-level drivers to prevent further | |
2314 | * commands from being queued to the device. | |
2315 | * | |
2316 | * Arguments: shost - Host in question | |
2317 | * | |
2318 | * Returns: Nothing | |
2319 | * | |
2320 | * Lock status: No locks are assumed held. | |
2321 | * | |
2322 | * Notes: There is no timer nor any other means by which the requests | |
2323 | * get unblocked other than the low-level driver calling | |
2324 | * scsi_unblock_requests(). | |
2325 | */ | |
2326 | void scsi_block_requests(struct Scsi_Host *shost) | |
2327 | { | |
2328 | shost->host_self_blocked = 1; | |
2329 | } | |
2330 | EXPORT_SYMBOL(scsi_block_requests); | |
2331 | ||
2332 | /* | |
2333 | * Function: scsi_unblock_requests() | |
2334 | * | |
2335 | * Purpose: Utility function used by low-level drivers to allow further | |
2336 | * commands from being queued to the device. | |
2337 | * | |
2338 | * Arguments: shost - Host in question | |
2339 | * | |
2340 | * Returns: Nothing | |
2341 | * | |
2342 | * Lock status: No locks are assumed held. | |
2343 | * | |
2344 | * Notes: There is no timer nor any other means by which the requests | |
2345 | * get unblocked other than the low-level driver calling | |
2346 | * scsi_unblock_requests(). | |
2347 | * | |
2348 | * This is done as an API function so that changes to the | |
2349 | * internals of the scsi mid-layer won't require wholesale | |
2350 | * changes to drivers that use this feature. | |
2351 | */ | |
2352 | void scsi_unblock_requests(struct Scsi_Host *shost) | |
2353 | { | |
2354 | shost->host_self_blocked = 0; | |
2355 | scsi_run_host_queues(shost); | |
2356 | } | |
2357 | EXPORT_SYMBOL(scsi_unblock_requests); | |
2358 | ||
2359 | int __init scsi_init_queue(void) | |
2360 | { | |
6362abd3 MP |
2361 | scsi_sdb_cache = kmem_cache_create("scsi_data_buffer", |
2362 | sizeof(struct scsi_data_buffer), | |
2363 | 0, 0, NULL); | |
2364 | if (!scsi_sdb_cache) { | |
2365 | printk(KERN_ERR "SCSI: can't init scsi sdb cache\n"); | |
f078727b | 2366 | return -ENOMEM; |
6f9a35e2 BH |
2367 | } |
2368 | ||
1da177e4 LT |
2369 | return 0; |
2370 | } | |
2371 | ||
2372 | void scsi_exit_queue(void) | |
2373 | { | |
0a6ac4ee CH |
2374 | kmem_cache_destroy(scsi_sense_cache); |
2375 | kmem_cache_destroy(scsi_sense_isadma_cache); | |
6362abd3 | 2376 | kmem_cache_destroy(scsi_sdb_cache); |
1da177e4 | 2377 | } |
5baba830 JB |
2378 | |
2379 | /** | |
2380 | * scsi_mode_select - issue a mode select | |
2381 | * @sdev: SCSI device to be queried | |
2382 | * @pf: Page format bit (1 == standard, 0 == vendor specific) | |
2383 | * @sp: Save page bit (0 == don't save, 1 == save) | |
2384 | * @modepage: mode page being requested | |
2385 | * @buffer: request buffer (may not be smaller than eight bytes) | |
2386 | * @len: length of request buffer. | |
2387 | * @timeout: command timeout | |
2388 | * @retries: number of retries before failing | |
2389 | * @data: returns a structure abstracting the mode header data | |
eb44820c | 2390 | * @sshdr: place to put sense data (or NULL if no sense to be collected). |
5baba830 JB |
2391 | * must be SCSI_SENSE_BUFFERSIZE big. |
2392 | * | |
2393 | * Returns zero if successful; negative error number or scsi | |
2394 | * status on error | |
2395 | * | |
2396 | */ | |
2397 | int | |
2398 | scsi_mode_select(struct scsi_device *sdev, int pf, int sp, int modepage, | |
2399 | unsigned char *buffer, int len, int timeout, int retries, | |
2400 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) | |
2401 | { | |
2402 | unsigned char cmd[10]; | |
2403 | unsigned char *real_buffer; | |
2404 | int ret; | |
2405 | ||
2406 | memset(cmd, 0, sizeof(cmd)); | |
2407 | cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0); | |
2408 | ||
2409 | if (sdev->use_10_for_ms) { | |
2410 | if (len > 65535) | |
2411 | return -EINVAL; | |
2412 | real_buffer = kmalloc(8 + len, GFP_KERNEL); | |
2413 | if (!real_buffer) | |
2414 | return -ENOMEM; | |
2415 | memcpy(real_buffer + 8, buffer, len); | |
2416 | len += 8; | |
2417 | real_buffer[0] = 0; | |
2418 | real_buffer[1] = 0; | |
2419 | real_buffer[2] = data->medium_type; | |
2420 | real_buffer[3] = data->device_specific; | |
2421 | real_buffer[4] = data->longlba ? 0x01 : 0; | |
2422 | real_buffer[5] = 0; | |
2423 | real_buffer[6] = data->block_descriptor_length >> 8; | |
2424 | real_buffer[7] = data->block_descriptor_length; | |
2425 | ||
2426 | cmd[0] = MODE_SELECT_10; | |
2427 | cmd[7] = len >> 8; | |
2428 | cmd[8] = len; | |
2429 | } else { | |
2430 | if (len > 255 || data->block_descriptor_length > 255 || | |
2431 | data->longlba) | |
2432 | return -EINVAL; | |
2433 | ||
2434 | real_buffer = kmalloc(4 + len, GFP_KERNEL); | |
2435 | if (!real_buffer) | |
2436 | return -ENOMEM; | |
2437 | memcpy(real_buffer + 4, buffer, len); | |
2438 | len += 4; | |
2439 | real_buffer[0] = 0; | |
2440 | real_buffer[1] = data->medium_type; | |
2441 | real_buffer[2] = data->device_specific; | |
2442 | real_buffer[3] = data->block_descriptor_length; | |
2443 | ||
2444 | ||
2445 | cmd[0] = MODE_SELECT; | |
2446 | cmd[4] = len; | |
2447 | } | |
2448 | ||
2449 | ret = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, real_buffer, len, | |
f4f4e47e | 2450 | sshdr, timeout, retries, NULL); |
5baba830 JB |
2451 | kfree(real_buffer); |
2452 | return ret; | |
2453 | } | |
2454 | EXPORT_SYMBOL_GPL(scsi_mode_select); | |
2455 | ||
1da177e4 | 2456 | /** |
eb44820c | 2457 | * scsi_mode_sense - issue a mode sense, falling back from 10 to six bytes if necessary. |
1cf72699 | 2458 | * @sdev: SCSI device to be queried |
1da177e4 LT |
2459 | * @dbd: set if mode sense will allow block descriptors to be returned |
2460 | * @modepage: mode page being requested | |
2461 | * @buffer: request buffer (may not be smaller than eight bytes) | |
2462 | * @len: length of request buffer. | |
2463 | * @timeout: command timeout | |
2464 | * @retries: number of retries before failing | |
2465 | * @data: returns a structure abstracting the mode header data | |
eb44820c | 2466 | * @sshdr: place to put sense data (or NULL if no sense to be collected). |
1cf72699 | 2467 | * must be SCSI_SENSE_BUFFERSIZE big. |
1da177e4 LT |
2468 | * |
2469 | * Returns zero if unsuccessful, or the header offset (either 4 | |
2470 | * or 8 depending on whether a six or ten byte command was | |
2471 | * issued) if successful. | |
eb44820c | 2472 | */ |
1da177e4 | 2473 | int |
1cf72699 | 2474 | scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, |
1da177e4 | 2475 | unsigned char *buffer, int len, int timeout, int retries, |
5baba830 JB |
2476 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) |
2477 | { | |
1da177e4 LT |
2478 | unsigned char cmd[12]; |
2479 | int use_10_for_ms; | |
2480 | int header_length; | |
0ae80ba9 | 2481 | int result, retry_count = retries; |
ea73a9f2 | 2482 | struct scsi_sense_hdr my_sshdr; |
1da177e4 LT |
2483 | |
2484 | memset(data, 0, sizeof(*data)); | |
2485 | memset(&cmd[0], 0, 12); | |
2486 | cmd[1] = dbd & 0x18; /* allows DBD and LLBA bits */ | |
2487 | cmd[2] = modepage; | |
2488 | ||
ea73a9f2 JB |
2489 | /* caller might not be interested in sense, but we need it */ |
2490 | if (!sshdr) | |
2491 | sshdr = &my_sshdr; | |
2492 | ||
1da177e4 | 2493 | retry: |
1cf72699 | 2494 | use_10_for_ms = sdev->use_10_for_ms; |
1da177e4 LT |
2495 | |
2496 | if (use_10_for_ms) { | |
2497 | if (len < 8) | |
2498 | len = 8; | |
2499 | ||
2500 | cmd[0] = MODE_SENSE_10; | |
2501 | cmd[8] = len; | |
2502 | header_length = 8; | |
2503 | } else { | |
2504 | if (len < 4) | |
2505 | len = 4; | |
2506 | ||
2507 | cmd[0] = MODE_SENSE; | |
2508 | cmd[4] = len; | |
2509 | header_length = 4; | |
2510 | } | |
2511 | ||
1da177e4 LT |
2512 | memset(buffer, 0, len); |
2513 | ||
1cf72699 | 2514 | result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len, |
f4f4e47e | 2515 | sshdr, timeout, retries, NULL); |
1da177e4 LT |
2516 | |
2517 | /* This code looks awful: what it's doing is making sure an | |
2518 | * ILLEGAL REQUEST sense return identifies the actual command | |
2519 | * byte as the problem. MODE_SENSE commands can return | |
2520 | * ILLEGAL REQUEST if the code page isn't supported */ | |
2521 | ||
1cf72699 JB |
2522 | if (use_10_for_ms && !scsi_status_is_good(result) && |
2523 | (driver_byte(result) & DRIVER_SENSE)) { | |
ea73a9f2 JB |
2524 | if (scsi_sense_valid(sshdr)) { |
2525 | if ((sshdr->sense_key == ILLEGAL_REQUEST) && | |
2526 | (sshdr->asc == 0x20) && (sshdr->ascq == 0)) { | |
1da177e4 LT |
2527 | /* |
2528 | * Invalid command operation code | |
2529 | */ | |
1cf72699 | 2530 | sdev->use_10_for_ms = 0; |
1da177e4 LT |
2531 | goto retry; |
2532 | } | |
2533 | } | |
2534 | } | |
2535 | ||
1cf72699 | 2536 | if(scsi_status_is_good(result)) { |
6d73c851 AV |
2537 | if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b && |
2538 | (modepage == 6 || modepage == 8))) { | |
2539 | /* Initio breakage? */ | |
2540 | header_length = 0; | |
2541 | data->length = 13; | |
2542 | data->medium_type = 0; | |
2543 | data->device_specific = 0; | |
2544 | data->longlba = 0; | |
2545 | data->block_descriptor_length = 0; | |
2546 | } else if(use_10_for_ms) { | |
1da177e4 LT |
2547 | data->length = buffer[0]*256 + buffer[1] + 2; |
2548 | data->medium_type = buffer[2]; | |
2549 | data->device_specific = buffer[3]; | |
2550 | data->longlba = buffer[4] & 0x01; | |
2551 | data->block_descriptor_length = buffer[6]*256 | |
2552 | + buffer[7]; | |
2553 | } else { | |
2554 | data->length = buffer[0] + 1; | |
2555 | data->medium_type = buffer[1]; | |
2556 | data->device_specific = buffer[2]; | |
2557 | data->block_descriptor_length = buffer[3]; | |
2558 | } | |
6d73c851 | 2559 | data->header_length = header_length; |
0ae80ba9 HR |
2560 | } else if ((status_byte(result) == CHECK_CONDITION) && |
2561 | scsi_sense_valid(sshdr) && | |
2562 | sshdr->sense_key == UNIT_ATTENTION && retry_count) { | |
2563 | retry_count--; | |
2564 | goto retry; | |
1da177e4 LT |
2565 | } |
2566 | ||
1cf72699 | 2567 | return result; |
1da177e4 LT |
2568 | } |
2569 | EXPORT_SYMBOL(scsi_mode_sense); | |
2570 | ||
001aac25 JB |
2571 | /** |
2572 | * scsi_test_unit_ready - test if unit is ready | |
2573 | * @sdev: scsi device to change the state of. | |
2574 | * @timeout: command timeout | |
2575 | * @retries: number of retries before failing | |
74a78ebd | 2576 | * @sshdr: outpout pointer for decoded sense information. |
001aac25 JB |
2577 | * |
2578 | * Returns zero if unsuccessful or an error if TUR failed. For | |
9f8a2c23 | 2579 | * removable media, UNIT_ATTENTION sets ->changed flag. |
001aac25 | 2580 | **/ |
1da177e4 | 2581 | int |
001aac25 | 2582 | scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries, |
74a78ebd | 2583 | struct scsi_sense_hdr *sshdr) |
1da177e4 | 2584 | { |
1da177e4 LT |
2585 | char cmd[] = { |
2586 | TEST_UNIT_READY, 0, 0, 0, 0, 0, | |
2587 | }; | |
2588 | int result; | |
001aac25 | 2589 | |
001aac25 JB |
2590 | /* try to eat the UNIT_ATTENTION if there are enough retries */ |
2591 | do { | |
2592 | result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, sshdr, | |
f4f4e47e | 2593 | timeout, retries, NULL); |
32c356d7 JB |
2594 | if (sdev->removable && scsi_sense_valid(sshdr) && |
2595 | sshdr->sense_key == UNIT_ATTENTION) | |
2596 | sdev->changed = 1; | |
2597 | } while (scsi_sense_valid(sshdr) && | |
2598 | sshdr->sense_key == UNIT_ATTENTION && --retries); | |
001aac25 | 2599 | |
1da177e4 LT |
2600 | return result; |
2601 | } | |
2602 | EXPORT_SYMBOL(scsi_test_unit_ready); | |
2603 | ||
2604 | /** | |
eb44820c | 2605 | * scsi_device_set_state - Take the given device through the device state model. |
1da177e4 LT |
2606 | * @sdev: scsi device to change the state of. |
2607 | * @state: state to change to. | |
2608 | * | |
23cb27fd | 2609 | * Returns zero if successful or an error if the requested |
1da177e4 | 2610 | * transition is illegal. |
eb44820c | 2611 | */ |
1da177e4 LT |
2612 | int |
2613 | scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) | |
2614 | { | |
2615 | enum scsi_device_state oldstate = sdev->sdev_state; | |
2616 | ||
2617 | if (state == oldstate) | |
2618 | return 0; | |
2619 | ||
2620 | switch (state) { | |
2621 | case SDEV_CREATED: | |
6f4267e3 JB |
2622 | switch (oldstate) { |
2623 | case SDEV_CREATED_BLOCK: | |
2624 | break; | |
2625 | default: | |
2626 | goto illegal; | |
2627 | } | |
2628 | break; | |
1da177e4 LT |
2629 | |
2630 | case SDEV_RUNNING: | |
2631 | switch (oldstate) { | |
2632 | case SDEV_CREATED: | |
2633 | case SDEV_OFFLINE: | |
1b8d2620 | 2634 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2635 | case SDEV_QUIESCE: |
2636 | case SDEV_BLOCK: | |
2637 | break; | |
2638 | default: | |
2639 | goto illegal; | |
2640 | } | |
2641 | break; | |
2642 | ||
2643 | case SDEV_QUIESCE: | |
2644 | switch (oldstate) { | |
2645 | case SDEV_RUNNING: | |
2646 | case SDEV_OFFLINE: | |
1b8d2620 | 2647 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2648 | break; |
2649 | default: | |
2650 | goto illegal; | |
2651 | } | |
2652 | break; | |
2653 | ||
2654 | case SDEV_OFFLINE: | |
1b8d2620 | 2655 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2656 | switch (oldstate) { |
2657 | case SDEV_CREATED: | |
2658 | case SDEV_RUNNING: | |
2659 | case SDEV_QUIESCE: | |
2660 | case SDEV_BLOCK: | |
2661 | break; | |
2662 | default: | |
2663 | goto illegal; | |
2664 | } | |
2665 | break; | |
2666 | ||
2667 | case SDEV_BLOCK: | |
2668 | switch (oldstate) { | |
1da177e4 | 2669 | case SDEV_RUNNING: |
6f4267e3 JB |
2670 | case SDEV_CREATED_BLOCK: |
2671 | break; | |
2672 | default: | |
2673 | goto illegal; | |
2674 | } | |
2675 | break; | |
2676 | ||
2677 | case SDEV_CREATED_BLOCK: | |
2678 | switch (oldstate) { | |
2679 | case SDEV_CREATED: | |
1da177e4 LT |
2680 | break; |
2681 | default: | |
2682 | goto illegal; | |
2683 | } | |
2684 | break; | |
2685 | ||
2686 | case SDEV_CANCEL: | |
2687 | switch (oldstate) { | |
2688 | case SDEV_CREATED: | |
2689 | case SDEV_RUNNING: | |
9ea72909 | 2690 | case SDEV_QUIESCE: |
1da177e4 | 2691 | case SDEV_OFFLINE: |
1b8d2620 | 2692 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2693 | break; |
2694 | default: | |
2695 | goto illegal; | |
2696 | } | |
2697 | break; | |
2698 | ||
2699 | case SDEV_DEL: | |
2700 | switch (oldstate) { | |
309bd271 BK |
2701 | case SDEV_CREATED: |
2702 | case SDEV_RUNNING: | |
2703 | case SDEV_OFFLINE: | |
1b8d2620 | 2704 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 | 2705 | case SDEV_CANCEL: |
255ee932 | 2706 | case SDEV_BLOCK: |
0516c08d | 2707 | case SDEV_CREATED_BLOCK: |
1da177e4 LT |
2708 | break; |
2709 | default: | |
2710 | goto illegal; | |
2711 | } | |
2712 | break; | |
2713 | ||
2714 | } | |
2715 | sdev->sdev_state = state; | |
2716 | return 0; | |
2717 | ||
2718 | illegal: | |
91921e01 | 2719 | SCSI_LOG_ERROR_RECOVERY(1, |
9ccfc756 | 2720 | sdev_printk(KERN_ERR, sdev, |
91921e01 | 2721 | "Illegal state transition %s->%s", |
9ccfc756 JB |
2722 | scsi_device_state_name(oldstate), |
2723 | scsi_device_state_name(state)) | |
1da177e4 LT |
2724 | ); |
2725 | return -EINVAL; | |
2726 | } | |
2727 | EXPORT_SYMBOL(scsi_device_set_state); | |
2728 | ||
a341cd0f JG |
2729 | /** |
2730 | * sdev_evt_emit - emit a single SCSI device uevent | |
2731 | * @sdev: associated SCSI device | |
2732 | * @evt: event to emit | |
2733 | * | |
2734 | * Send a single uevent (scsi_event) to the associated scsi_device. | |
2735 | */ | |
2736 | static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt) | |
2737 | { | |
2738 | int idx = 0; | |
2739 | char *envp[3]; | |
2740 | ||
2741 | switch (evt->evt_type) { | |
2742 | case SDEV_EVT_MEDIA_CHANGE: | |
2743 | envp[idx++] = "SDEV_MEDIA_CHANGE=1"; | |
2744 | break; | |
279afdfe | 2745 | case SDEV_EVT_INQUIRY_CHANGE_REPORTED: |
d3d32891 | 2746 | scsi_rescan_device(&sdev->sdev_gendev); |
279afdfe EM |
2747 | envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED"; |
2748 | break; | |
2749 | case SDEV_EVT_CAPACITY_CHANGE_REPORTED: | |
2750 | envp[idx++] = "SDEV_UA=CAPACITY_DATA_HAS_CHANGED"; | |
2751 | break; | |
2752 | case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED: | |
2753 | envp[idx++] = "SDEV_UA=THIN_PROVISIONING_SOFT_THRESHOLD_REACHED"; | |
2754 | break; | |
2755 | case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED: | |
2756 | envp[idx++] = "SDEV_UA=MODE_PARAMETERS_CHANGED"; | |
2757 | break; | |
2758 | case SDEV_EVT_LUN_CHANGE_REPORTED: | |
2759 | envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED"; | |
2760 | break; | |
14c3e677 HR |
2761 | case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED: |
2762 | envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED"; | |
2763 | break; | |
cf3431bb HR |
2764 | case SDEV_EVT_POWER_ON_RESET_OCCURRED: |
2765 | envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED"; | |
2766 | break; | |
a341cd0f JG |
2767 | default: |
2768 | /* do nothing */ | |
2769 | break; | |
2770 | } | |
2771 | ||
2772 | envp[idx++] = NULL; | |
2773 | ||
2774 | kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp); | |
2775 | } | |
2776 | ||
2777 | /** | |
2778 | * sdev_evt_thread - send a uevent for each scsi event | |
2779 | * @work: work struct for scsi_device | |
2780 | * | |
2781 | * Dispatch queued events to their associated scsi_device kobjects | |
2782 | * as uevents. | |
2783 | */ | |
2784 | void scsi_evt_thread(struct work_struct *work) | |
2785 | { | |
2786 | struct scsi_device *sdev; | |
279afdfe | 2787 | enum scsi_device_event evt_type; |
a341cd0f JG |
2788 | LIST_HEAD(event_list); |
2789 | ||
2790 | sdev = container_of(work, struct scsi_device, event_work); | |
2791 | ||
279afdfe EM |
2792 | for (evt_type = SDEV_EVT_FIRST; evt_type <= SDEV_EVT_LAST; evt_type++) |
2793 | if (test_and_clear_bit(evt_type, sdev->pending_events)) | |
2794 | sdev_evt_send_simple(sdev, evt_type, GFP_KERNEL); | |
2795 | ||
a341cd0f JG |
2796 | while (1) { |
2797 | struct scsi_event *evt; | |
2798 | struct list_head *this, *tmp; | |
2799 | unsigned long flags; | |
2800 | ||
2801 | spin_lock_irqsave(&sdev->list_lock, flags); | |
2802 | list_splice_init(&sdev->event_list, &event_list); | |
2803 | spin_unlock_irqrestore(&sdev->list_lock, flags); | |
2804 | ||
2805 | if (list_empty(&event_list)) | |
2806 | break; | |
2807 | ||
2808 | list_for_each_safe(this, tmp, &event_list) { | |
2809 | evt = list_entry(this, struct scsi_event, node); | |
2810 | list_del(&evt->node); | |
2811 | scsi_evt_emit(sdev, evt); | |
2812 | kfree(evt); | |
2813 | } | |
2814 | } | |
2815 | } | |
2816 | ||
2817 | /** | |
2818 | * sdev_evt_send - send asserted event to uevent thread | |
2819 | * @sdev: scsi_device event occurred on | |
2820 | * @evt: event to send | |
2821 | * | |
2822 | * Assert scsi device event asynchronously. | |
2823 | */ | |
2824 | void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt) | |
2825 | { | |
2826 | unsigned long flags; | |
2827 | ||
4d1566ed KS |
2828 | #if 0 |
2829 | /* FIXME: currently this check eliminates all media change events | |
2830 | * for polled devices. Need to update to discriminate between AN | |
2831 | * and polled events */ | |
a341cd0f JG |
2832 | if (!test_bit(evt->evt_type, sdev->supported_events)) { |
2833 | kfree(evt); | |
2834 | return; | |
2835 | } | |
4d1566ed | 2836 | #endif |
a341cd0f JG |
2837 | |
2838 | spin_lock_irqsave(&sdev->list_lock, flags); | |
2839 | list_add_tail(&evt->node, &sdev->event_list); | |
2840 | schedule_work(&sdev->event_work); | |
2841 | spin_unlock_irqrestore(&sdev->list_lock, flags); | |
2842 | } | |
2843 | EXPORT_SYMBOL_GPL(sdev_evt_send); | |
2844 | ||
2845 | /** | |
2846 | * sdev_evt_alloc - allocate a new scsi event | |
2847 | * @evt_type: type of event to allocate | |
2848 | * @gfpflags: GFP flags for allocation | |
2849 | * | |
2850 | * Allocates and returns a new scsi_event. | |
2851 | */ | |
2852 | struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type, | |
2853 | gfp_t gfpflags) | |
2854 | { | |
2855 | struct scsi_event *evt = kzalloc(sizeof(struct scsi_event), gfpflags); | |
2856 | if (!evt) | |
2857 | return NULL; | |
2858 | ||
2859 | evt->evt_type = evt_type; | |
2860 | INIT_LIST_HEAD(&evt->node); | |
2861 | ||
2862 | /* evt_type-specific initialization, if any */ | |
2863 | switch (evt_type) { | |
2864 | case SDEV_EVT_MEDIA_CHANGE: | |
279afdfe EM |
2865 | case SDEV_EVT_INQUIRY_CHANGE_REPORTED: |
2866 | case SDEV_EVT_CAPACITY_CHANGE_REPORTED: | |
2867 | case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED: | |
2868 | case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED: | |
2869 | case SDEV_EVT_LUN_CHANGE_REPORTED: | |
14c3e677 | 2870 | case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED: |
cf3431bb | 2871 | case SDEV_EVT_POWER_ON_RESET_OCCURRED: |
a341cd0f JG |
2872 | default: |
2873 | /* do nothing */ | |
2874 | break; | |
2875 | } | |
2876 | ||
2877 | return evt; | |
2878 | } | |
2879 | EXPORT_SYMBOL_GPL(sdev_evt_alloc); | |
2880 | ||
2881 | /** | |
2882 | * sdev_evt_send_simple - send asserted event to uevent thread | |
2883 | * @sdev: scsi_device event occurred on | |
2884 | * @evt_type: type of event to send | |
2885 | * @gfpflags: GFP flags for allocation | |
2886 | * | |
2887 | * Assert scsi device event asynchronously, given an event type. | |
2888 | */ | |
2889 | void sdev_evt_send_simple(struct scsi_device *sdev, | |
2890 | enum scsi_device_event evt_type, gfp_t gfpflags) | |
2891 | { | |
2892 | struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags); | |
2893 | if (!evt) { | |
2894 | sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n", | |
2895 | evt_type); | |
2896 | return; | |
2897 | } | |
2898 | ||
2899 | sdev_evt_send(sdev, evt); | |
2900 | } | |
2901 | EXPORT_SYMBOL_GPL(sdev_evt_send_simple); | |
2902 | ||
669f0441 BVA |
2903 | /** |
2904 | * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn() | |
2905 | * @sdev: SCSI device to count the number of scsi_request_fn() callers for. | |
2906 | */ | |
2907 | static int scsi_request_fn_active(struct scsi_device *sdev) | |
2908 | { | |
2909 | struct request_queue *q = sdev->request_queue; | |
2910 | int request_fn_active; | |
2911 | ||
2912 | WARN_ON_ONCE(sdev->host->use_blk_mq); | |
2913 | ||
2914 | spin_lock_irq(q->queue_lock); | |
2915 | request_fn_active = q->request_fn_active; | |
2916 | spin_unlock_irq(q->queue_lock); | |
2917 | ||
2918 | return request_fn_active; | |
2919 | } | |
2920 | ||
2921 | /** | |
2922 | * scsi_wait_for_queuecommand() - wait for ongoing queuecommand() calls | |
2923 | * @sdev: SCSI device pointer. | |
2924 | * | |
2925 | * Wait until the ongoing shost->hostt->queuecommand() calls that are | |
2926 | * invoked from scsi_request_fn() have finished. | |
2927 | */ | |
2928 | static void scsi_wait_for_queuecommand(struct scsi_device *sdev) | |
2929 | { | |
2930 | WARN_ON_ONCE(sdev->host->use_blk_mq); | |
2931 | ||
2932 | while (scsi_request_fn_active(sdev)) | |
2933 | msleep(20); | |
2934 | } | |
2935 | ||
1da177e4 LT |
2936 | /** |
2937 | * scsi_device_quiesce - Block user issued commands. | |
2938 | * @sdev: scsi device to quiesce. | |
2939 | * | |
2940 | * This works by trying to transition to the SDEV_QUIESCE state | |
2941 | * (which must be a legal transition). When the device is in this | |
2942 | * state, only special requests will be accepted, all others will | |
2943 | * be deferred. Since special requests may also be requeued requests, | |
2944 | * a successful return doesn't guarantee the device will be | |
2945 | * totally quiescent. | |
2946 | * | |
2947 | * Must be called with user context, may sleep. | |
2948 | * | |
2949 | * Returns zero if unsuccessful or an error if not. | |
eb44820c | 2950 | */ |
1da177e4 LT |
2951 | int |
2952 | scsi_device_quiesce(struct scsi_device *sdev) | |
2953 | { | |
3a0a5299 | 2954 | struct request_queue *q = sdev->request_queue; |
0db6ca8a BVA |
2955 | int err; |
2956 | ||
3a0a5299 BVA |
2957 | /* |
2958 | * It is allowed to call scsi_device_quiesce() multiple times from | |
2959 | * the same context but concurrent scsi_device_quiesce() calls are | |
2960 | * not allowed. | |
2961 | */ | |
2962 | WARN_ON_ONCE(sdev->quiesced_by && sdev->quiesced_by != current); | |
2963 | ||
2964 | blk_set_preempt_only(q); | |
2965 | ||
2966 | blk_mq_freeze_queue(q); | |
2967 | /* | |
2968 | * Ensure that the effect of blk_set_preempt_only() will be visible | |
2969 | * for percpu_ref_tryget() callers that occur after the queue | |
2970 | * unfreeze even if the queue was already frozen before this function | |
2971 | * was called. See also https://lwn.net/Articles/573497/. | |
2972 | */ | |
2973 | synchronize_rcu(); | |
2974 | blk_mq_unfreeze_queue(q); | |
2975 | ||
0db6ca8a BVA |
2976 | mutex_lock(&sdev->state_mutex); |
2977 | err = scsi_device_set_state(sdev, SDEV_QUIESCE); | |
3a0a5299 BVA |
2978 | if (err == 0) |
2979 | sdev->quiesced_by = current; | |
2980 | else | |
2981 | blk_clear_preempt_only(q); | |
0db6ca8a BVA |
2982 | mutex_unlock(&sdev->state_mutex); |
2983 | ||
3a0a5299 | 2984 | return err; |
1da177e4 LT |
2985 | } |
2986 | EXPORT_SYMBOL(scsi_device_quiesce); | |
2987 | ||
2988 | /** | |
2989 | * scsi_device_resume - Restart user issued commands to a quiesced device. | |
2990 | * @sdev: scsi device to resume. | |
2991 | * | |
2992 | * Moves the device from quiesced back to running and restarts the | |
2993 | * queues. | |
2994 | * | |
2995 | * Must be called with user context, may sleep. | |
eb44820c | 2996 | */ |
a7a20d10 | 2997 | void scsi_device_resume(struct scsi_device *sdev) |
1da177e4 | 2998 | { |
a7a20d10 DW |
2999 | /* check if the device state was mutated prior to resume, and if |
3000 | * so assume the state is being managed elsewhere (for example | |
3001 | * device deleted during suspend) | |
3002 | */ | |
0db6ca8a | 3003 | mutex_lock(&sdev->state_mutex); |
3a0a5299 BVA |
3004 | WARN_ON_ONCE(!sdev->quiesced_by); |
3005 | sdev->quiesced_by = NULL; | |
3006 | blk_clear_preempt_only(sdev->request_queue); | |
3007 | if (sdev->sdev_state == SDEV_QUIESCE) | |
3008 | scsi_device_set_state(sdev, SDEV_RUNNING); | |
0db6ca8a | 3009 | mutex_unlock(&sdev->state_mutex); |
1da177e4 LT |
3010 | } |
3011 | EXPORT_SYMBOL(scsi_device_resume); | |
3012 | ||
3013 | static void | |
3014 | device_quiesce_fn(struct scsi_device *sdev, void *data) | |
3015 | { | |
3016 | scsi_device_quiesce(sdev); | |
3017 | } | |
3018 | ||
3019 | void | |
3020 | scsi_target_quiesce(struct scsi_target *starget) | |
3021 | { | |
3022 | starget_for_each_device(starget, NULL, device_quiesce_fn); | |
3023 | } | |
3024 | EXPORT_SYMBOL(scsi_target_quiesce); | |
3025 | ||
3026 | static void | |
3027 | device_resume_fn(struct scsi_device *sdev, void *data) | |
3028 | { | |
3029 | scsi_device_resume(sdev); | |
3030 | } | |
3031 | ||
3032 | void | |
3033 | scsi_target_resume(struct scsi_target *starget) | |
3034 | { | |
3035 | starget_for_each_device(starget, NULL, device_resume_fn); | |
3036 | } | |
3037 | EXPORT_SYMBOL(scsi_target_resume); | |
3038 | ||
3039 | /** | |
551eb598 BVA |
3040 | * scsi_internal_device_block_nowait - try to transition to the SDEV_BLOCK state |
3041 | * @sdev: device to block | |
1da177e4 | 3042 | * |
551eb598 | 3043 | * Pause SCSI command processing on the specified device. Does not sleep. |
1da177e4 | 3044 | * |
551eb598 | 3045 | * Returns zero if successful or a negative error code upon failure. |
669f0441 | 3046 | * |
551eb598 BVA |
3047 | * Notes: |
3048 | * This routine transitions the device to the SDEV_BLOCK state (which must be | |
3049 | * a legal transition). When the device is in this state, command processing | |
3050 | * is paused until the device leaves the SDEV_BLOCK state. See also | |
3051 | * scsi_internal_device_unblock_nowait(). | |
eb44820c | 3052 | */ |
551eb598 | 3053 | int scsi_internal_device_block_nowait(struct scsi_device *sdev) |
1da177e4 | 3054 | { |
165125e1 | 3055 | struct request_queue *q = sdev->request_queue; |
1da177e4 LT |
3056 | unsigned long flags; |
3057 | int err = 0; | |
3058 | ||
3059 | err = scsi_device_set_state(sdev, SDEV_BLOCK); | |
6f4267e3 JB |
3060 | if (err) { |
3061 | err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); | |
3062 | ||
3063 | if (err) | |
3064 | return err; | |
3065 | } | |
1da177e4 LT |
3066 | |
3067 | /* | |
3068 | * The device has transitioned to SDEV_BLOCK. Stop the | |
3069 | * block layer from calling the midlayer with this device's | |
3070 | * request queue. | |
3071 | */ | |
d285203c | 3072 | if (q->mq_ops) { |
90311148 | 3073 | blk_mq_quiesce_queue_nowait(q); |
d285203c CH |
3074 | } else { |
3075 | spin_lock_irqsave(q->queue_lock, flags); | |
3076 | blk_stop_queue(q); | |
3077 | spin_unlock_irqrestore(q->queue_lock, flags); | |
3078 | } | |
1da177e4 LT |
3079 | |
3080 | return 0; | |
3081 | } | |
551eb598 BVA |
3082 | EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait); |
3083 | ||
1da177e4 | 3084 | /** |
551eb598 BVA |
3085 | * scsi_internal_device_block - try to transition to the SDEV_BLOCK state |
3086 | * @sdev: device to block | |
3087 | * | |
3088 | * Pause SCSI command processing on the specified device and wait until all | |
3089 | * ongoing scsi_request_fn() / scsi_queue_rq() calls have finished. May sleep. | |
1da177e4 | 3090 | * |
551eb598 | 3091 | * Returns zero if successful or a negative error code upon failure. |
1da177e4 | 3092 | * |
551eb598 BVA |
3093 | * Note: |
3094 | * This routine transitions the device to the SDEV_BLOCK state (which must be | |
3095 | * a legal transition). When the device is in this state, command processing | |
3096 | * is paused until the device leaves the SDEV_BLOCK state. See also | |
3097 | * scsi_internal_device_unblock(). | |
1da177e4 | 3098 | * |
551eb598 BVA |
3099 | * To do: avoid that scsi_send_eh_cmnd() calls queuecommand() after |
3100 | * scsi_internal_device_block() has blocked a SCSI device and also | |
3101 | * remove the rport mutex lock and unlock calls from srp_queuecommand(). | |
eb44820c | 3102 | */ |
551eb598 | 3103 | static int scsi_internal_device_block(struct scsi_device *sdev) |
1da177e4 | 3104 | { |
551eb598 BVA |
3105 | struct request_queue *q = sdev->request_queue; |
3106 | int err; | |
3107 | ||
0db6ca8a | 3108 | mutex_lock(&sdev->state_mutex); |
551eb598 BVA |
3109 | err = scsi_internal_device_block_nowait(sdev); |
3110 | if (err == 0) { | |
3111 | if (q->mq_ops) | |
3112 | blk_mq_quiesce_queue(q); | |
3113 | else | |
3114 | scsi_wait_for_queuecommand(sdev); | |
3115 | } | |
0db6ca8a BVA |
3116 | mutex_unlock(&sdev->state_mutex); |
3117 | ||
551eb598 BVA |
3118 | return err; |
3119 | } | |
1da177e4 | 3120 | |
66483a4a BVA |
3121 | void scsi_start_queue(struct scsi_device *sdev) |
3122 | { | |
3123 | struct request_queue *q = sdev->request_queue; | |
1da177e4 | 3124 | unsigned long flags; |
5d9fb5cc | 3125 | |
66483a4a | 3126 | if (q->mq_ops) { |
90311148 | 3127 | blk_mq_unquiesce_queue(q); |
66483a4a BVA |
3128 | } else { |
3129 | spin_lock_irqsave(q->queue_lock, flags); | |
3130 | blk_start_queue(q); | |
3131 | spin_unlock_irqrestore(q->queue_lock, flags); | |
3132 | } | |
3133 | } | |
3134 | ||
1da177e4 | 3135 | /** |
43f7571b | 3136 | * scsi_internal_device_unblock_nowait - resume a device after a block request |
1da177e4 | 3137 | * @sdev: device to resume |
43f7571b | 3138 | * @new_state: state to set the device to after unblocking |
1da177e4 | 3139 | * |
43f7571b BVA |
3140 | * Restart the device queue for a previously suspended SCSI device. Does not |
3141 | * sleep. | |
1da177e4 | 3142 | * |
43f7571b | 3143 | * Returns zero if successful or a negative error code upon failure. |
1da177e4 | 3144 | * |
43f7571b BVA |
3145 | * Notes: |
3146 | * This routine transitions the device to the SDEV_RUNNING state or to one of | |
3147 | * the offline states (which must be a legal transition) allowing the midlayer | |
3148 | * to goose the queue for this device. | |
eb44820c | 3149 | */ |
43f7571b BVA |
3150 | int scsi_internal_device_unblock_nowait(struct scsi_device *sdev, |
3151 | enum scsi_device_state new_state) | |
1da177e4 | 3152 | { |
5d9fb5cc MC |
3153 | /* |
3154 | * Try to transition the scsi device to SDEV_RUNNING or one of the | |
3155 | * offlined states and goose the device queue if successful. | |
1da177e4 | 3156 | */ |
8cd1ec78 HR |
3157 | switch (sdev->sdev_state) { |
3158 | case SDEV_BLOCK: | |
3159 | case SDEV_TRANSPORT_OFFLINE: | |
5d9fb5cc | 3160 | sdev->sdev_state = new_state; |
8cd1ec78 HR |
3161 | break; |
3162 | case SDEV_CREATED_BLOCK: | |
5d9fb5cc MC |
3163 | if (new_state == SDEV_TRANSPORT_OFFLINE || |
3164 | new_state == SDEV_OFFLINE) | |
3165 | sdev->sdev_state = new_state; | |
3166 | else | |
3167 | sdev->sdev_state = SDEV_CREATED; | |
8cd1ec78 HR |
3168 | break; |
3169 | case SDEV_CANCEL: | |
3170 | case SDEV_OFFLINE: | |
3171 | break; | |
3172 | default: | |
5c10e63c | 3173 | return -EINVAL; |
8cd1ec78 | 3174 | } |
66483a4a | 3175 | scsi_start_queue(sdev); |
1da177e4 LT |
3176 | |
3177 | return 0; | |
3178 | } | |
43f7571b BVA |
3179 | EXPORT_SYMBOL_GPL(scsi_internal_device_unblock_nowait); |
3180 | ||
3181 | /** | |
3182 | * scsi_internal_device_unblock - resume a device after a block request | |
3183 | * @sdev: device to resume | |
3184 | * @new_state: state to set the device to after unblocking | |
3185 | * | |
3186 | * Restart the device queue for a previously suspended SCSI device. May sleep. | |
3187 | * | |
3188 | * Returns zero if successful or a negative error code upon failure. | |
3189 | * | |
3190 | * Notes: | |
3191 | * This routine transitions the device to the SDEV_RUNNING state or to one of | |
3192 | * the offline states (which must be a legal transition) allowing the midlayer | |
3193 | * to goose the queue for this device. | |
3194 | */ | |
3195 | static int scsi_internal_device_unblock(struct scsi_device *sdev, | |
3196 | enum scsi_device_state new_state) | |
3197 | { | |
0db6ca8a BVA |
3198 | int ret; |
3199 | ||
3200 | mutex_lock(&sdev->state_mutex); | |
3201 | ret = scsi_internal_device_unblock_nowait(sdev, new_state); | |
3202 | mutex_unlock(&sdev->state_mutex); | |
3203 | ||
3204 | return ret; | |
43f7571b | 3205 | } |
1da177e4 LT |
3206 | |
3207 | static void | |
3208 | device_block(struct scsi_device *sdev, void *data) | |
3209 | { | |
551eb598 | 3210 | scsi_internal_device_block(sdev); |
1da177e4 LT |
3211 | } |
3212 | ||
3213 | static int | |
3214 | target_block(struct device *dev, void *data) | |
3215 | { | |
3216 | if (scsi_is_target_device(dev)) | |
3217 | starget_for_each_device(to_scsi_target(dev), NULL, | |
3218 | device_block); | |
3219 | return 0; | |
3220 | } | |
3221 | ||
3222 | void | |
3223 | scsi_target_block(struct device *dev) | |
3224 | { | |
3225 | if (scsi_is_target_device(dev)) | |
3226 | starget_for_each_device(to_scsi_target(dev), NULL, | |
3227 | device_block); | |
3228 | else | |
3229 | device_for_each_child(dev, NULL, target_block); | |
3230 | } | |
3231 | EXPORT_SYMBOL_GPL(scsi_target_block); | |
3232 | ||
3233 | static void | |
3234 | device_unblock(struct scsi_device *sdev, void *data) | |
3235 | { | |
5d9fb5cc | 3236 | scsi_internal_device_unblock(sdev, *(enum scsi_device_state *)data); |
1da177e4 LT |
3237 | } |
3238 | ||
3239 | static int | |
3240 | target_unblock(struct device *dev, void *data) | |
3241 | { | |
3242 | if (scsi_is_target_device(dev)) | |
5d9fb5cc | 3243 | starget_for_each_device(to_scsi_target(dev), data, |
1da177e4 LT |
3244 | device_unblock); |
3245 | return 0; | |
3246 | } | |
3247 | ||
3248 | void | |
5d9fb5cc | 3249 | scsi_target_unblock(struct device *dev, enum scsi_device_state new_state) |
1da177e4 LT |
3250 | { |
3251 | if (scsi_is_target_device(dev)) | |
5d9fb5cc | 3252 | starget_for_each_device(to_scsi_target(dev), &new_state, |
1da177e4 LT |
3253 | device_unblock); |
3254 | else | |
5d9fb5cc | 3255 | device_for_each_child(dev, &new_state, target_unblock); |
1da177e4 LT |
3256 | } |
3257 | EXPORT_SYMBOL_GPL(scsi_target_unblock); | |
cdb8c2a6 GL |
3258 | |
3259 | /** | |
3260 | * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt | |
eb44820c | 3261 | * @sgl: scatter-gather list |
cdb8c2a6 GL |
3262 | * @sg_count: number of segments in sg |
3263 | * @offset: offset in bytes into sg, on return offset into the mapped area | |
3264 | * @len: bytes to map, on return number of bytes mapped | |
3265 | * | |
3266 | * Returns virtual address of the start of the mapped page | |
3267 | */ | |
c6132da1 | 3268 | void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count, |
cdb8c2a6 GL |
3269 | size_t *offset, size_t *len) |
3270 | { | |
3271 | int i; | |
3272 | size_t sg_len = 0, len_complete = 0; | |
c6132da1 | 3273 | struct scatterlist *sg; |
cdb8c2a6 GL |
3274 | struct page *page; |
3275 | ||
22cfefb5 AM |
3276 | WARN_ON(!irqs_disabled()); |
3277 | ||
c6132da1 | 3278 | for_each_sg(sgl, sg, sg_count, i) { |
cdb8c2a6 | 3279 | len_complete = sg_len; /* Complete sg-entries */ |
c6132da1 | 3280 | sg_len += sg->length; |
cdb8c2a6 GL |
3281 | if (sg_len > *offset) |
3282 | break; | |
3283 | } | |
3284 | ||
3285 | if (unlikely(i == sg_count)) { | |
169e1a2a AM |
3286 | printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, " |
3287 | "elements %d\n", | |
cadbd4a5 | 3288 | __func__, sg_len, *offset, sg_count); |
cdb8c2a6 GL |
3289 | WARN_ON(1); |
3290 | return NULL; | |
3291 | } | |
3292 | ||
3293 | /* Offset starting from the beginning of first page in this sg-entry */ | |
c6132da1 | 3294 | *offset = *offset - len_complete + sg->offset; |
cdb8c2a6 GL |
3295 | |
3296 | /* Assumption: contiguous pages can be accessed as "page + i" */ | |
45711f1a | 3297 | page = nth_page(sg_page(sg), (*offset >> PAGE_SHIFT)); |
cdb8c2a6 GL |
3298 | *offset &= ~PAGE_MASK; |
3299 | ||
3300 | /* Bytes in this sg-entry from *offset to the end of the page */ | |
3301 | sg_len = PAGE_SIZE - *offset; | |
3302 | if (*len > sg_len) | |
3303 | *len = sg_len; | |
3304 | ||
77dfce07 | 3305 | return kmap_atomic(page); |
cdb8c2a6 GL |
3306 | } |
3307 | EXPORT_SYMBOL(scsi_kmap_atomic_sg); | |
3308 | ||
3309 | /** | |
eb44820c | 3310 | * scsi_kunmap_atomic_sg - atomically unmap a virtual address, previously mapped with scsi_kmap_atomic_sg |
cdb8c2a6 GL |
3311 | * @virt: virtual address to be unmapped |
3312 | */ | |
3313 | void scsi_kunmap_atomic_sg(void *virt) | |
3314 | { | |
77dfce07 | 3315 | kunmap_atomic(virt); |
cdb8c2a6 GL |
3316 | } |
3317 | EXPORT_SYMBOL(scsi_kunmap_atomic_sg); | |
6f4c827e AL |
3318 | |
3319 | void sdev_disable_disk_events(struct scsi_device *sdev) | |
3320 | { | |
3321 | atomic_inc(&sdev->disk_events_disable_depth); | |
3322 | } | |
3323 | EXPORT_SYMBOL(sdev_disable_disk_events); | |
3324 | ||
3325 | void sdev_enable_disk_events(struct scsi_device *sdev) | |
3326 | { | |
3327 | if (WARN_ON_ONCE(atomic_read(&sdev->disk_events_disable_depth) <= 0)) | |
3328 | return; | |
3329 | atomic_dec(&sdev->disk_events_disable_depth); | |
3330 | } | |
3331 | EXPORT_SYMBOL(sdev_enable_disk_events); | |
9983bed3 HR |
3332 | |
3333 | /** | |
3334 | * scsi_vpd_lun_id - return a unique device identification | |
3335 | * @sdev: SCSI device | |
3336 | * @id: buffer for the identification | |
3337 | * @id_len: length of the buffer | |
3338 | * | |
3339 | * Copies a unique device identification into @id based | |
3340 | * on the information in the VPD page 0x83 of the device. | |
3341 | * The string will be formatted as a SCSI name string. | |
3342 | * | |
3343 | * Returns the length of the identification or error on failure. | |
3344 | * If the identifier is longer than the supplied buffer the actual | |
3345 | * identifier length is returned and the buffer is not zero-padded. | |
3346 | */ | |
3347 | int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len) | |
3348 | { | |
3349 | u8 cur_id_type = 0xff; | |
3350 | u8 cur_id_size = 0; | |
ccf1e004 BVA |
3351 | const unsigned char *d, *cur_id_str; |
3352 | const struct scsi_vpd *vpd_pg83; | |
9983bed3 HR |
3353 | int id_size = -EINVAL; |
3354 | ||
3355 | rcu_read_lock(); | |
3356 | vpd_pg83 = rcu_dereference(sdev->vpd_pg83); | |
3357 | if (!vpd_pg83) { | |
3358 | rcu_read_unlock(); | |
3359 | return -ENXIO; | |
3360 | } | |
3361 | ||
3362 | /* | |
3363 | * Look for the correct descriptor. | |
3364 | * Order of preference for lun descriptor: | |
3365 | * - SCSI name string | |
3366 | * - NAA IEEE Registered Extended | |
3367 | * - EUI-64 based 16-byte | |
3368 | * - EUI-64 based 12-byte | |
3369 | * - NAA IEEE Registered | |
3370 | * - NAA IEEE Extended | |
d230823a | 3371 | * - T10 Vendor ID |
9983bed3 HR |
3372 | * as longer descriptors reduce the likelyhood |
3373 | * of identification clashes. | |
3374 | */ | |
3375 | ||
3376 | /* The id string must be at least 20 bytes + terminating NULL byte */ | |
3377 | if (id_len < 21) { | |
3378 | rcu_read_unlock(); | |
3379 | return -EINVAL; | |
3380 | } | |
3381 | ||
3382 | memset(id, 0, id_len); | |
ccf1e004 BVA |
3383 | d = vpd_pg83->data + 4; |
3384 | while (d < vpd_pg83->data + vpd_pg83->len) { | |
9983bed3 HR |
3385 | /* Skip designators not referring to the LUN */ |
3386 | if ((d[1] & 0x30) != 0x00) | |
3387 | goto next_desig; | |
3388 | ||
3389 | switch (d[1] & 0xf) { | |
d230823a HR |
3390 | case 0x1: |
3391 | /* T10 Vendor ID */ | |
3392 | if (cur_id_size > d[3]) | |
3393 | break; | |
3394 | /* Prefer anything */ | |
3395 | if (cur_id_type > 0x01 && cur_id_type != 0xff) | |
3396 | break; | |
3397 | cur_id_size = d[3]; | |
3398 | if (cur_id_size + 4 > id_len) | |
3399 | cur_id_size = id_len - 4; | |
3400 | cur_id_str = d + 4; | |
3401 | cur_id_type = d[1] & 0xf; | |
3402 | id_size = snprintf(id, id_len, "t10.%*pE", | |
3403 | cur_id_size, cur_id_str); | |
3404 | break; | |
9983bed3 HR |
3405 | case 0x2: |
3406 | /* EUI-64 */ | |
3407 | if (cur_id_size > d[3]) | |
3408 | break; | |
3409 | /* Prefer NAA IEEE Registered Extended */ | |
3410 | if (cur_id_type == 0x3 && | |
3411 | cur_id_size == d[3]) | |
3412 | break; | |
3413 | cur_id_size = d[3]; | |
3414 | cur_id_str = d + 4; | |
3415 | cur_id_type = d[1] & 0xf; | |
3416 | switch (cur_id_size) { | |
3417 | case 8: | |
3418 | id_size = snprintf(id, id_len, | |
3419 | "eui.%8phN", | |
3420 | cur_id_str); | |
3421 | break; | |
3422 | case 12: | |
3423 | id_size = snprintf(id, id_len, | |
3424 | "eui.%12phN", | |
3425 | cur_id_str); | |
3426 | break; | |
3427 | case 16: | |
3428 | id_size = snprintf(id, id_len, | |
3429 | "eui.%16phN", | |
3430 | cur_id_str); | |
3431 | break; | |
3432 | default: | |
3433 | cur_id_size = 0; | |
3434 | break; | |
3435 | } | |
3436 | break; | |
3437 | case 0x3: | |
3438 | /* NAA */ | |
3439 | if (cur_id_size > d[3]) | |
3440 | break; | |
3441 | cur_id_size = d[3]; | |
3442 | cur_id_str = d + 4; | |
3443 | cur_id_type = d[1] & 0xf; | |
3444 | switch (cur_id_size) { | |
3445 | case 8: | |
3446 | id_size = snprintf(id, id_len, | |
3447 | "naa.%8phN", | |
3448 | cur_id_str); | |
3449 | break; | |
3450 | case 16: | |
3451 | id_size = snprintf(id, id_len, | |
3452 | "naa.%16phN", | |
3453 | cur_id_str); | |
3454 | break; | |
3455 | default: | |
3456 | cur_id_size = 0; | |
3457 | break; | |
3458 | } | |
3459 | break; | |
3460 | case 0x8: | |
3461 | /* SCSI name string */ | |
3462 | if (cur_id_size + 4 > d[3]) | |
3463 | break; | |
3464 | /* Prefer others for truncated descriptor */ | |
3465 | if (cur_id_size && d[3] > id_len) | |
3466 | break; | |
3467 | cur_id_size = id_size = d[3]; | |
3468 | cur_id_str = d + 4; | |
3469 | cur_id_type = d[1] & 0xf; | |
3470 | if (cur_id_size >= id_len) | |
3471 | cur_id_size = id_len - 1; | |
3472 | memcpy(id, cur_id_str, cur_id_size); | |
3473 | /* Decrease priority for truncated descriptor */ | |
3474 | if (cur_id_size != id_size) | |
3475 | cur_id_size = 6; | |
3476 | break; | |
3477 | default: | |
3478 | break; | |
3479 | } | |
3480 | next_desig: | |
3481 | d += d[3] + 4; | |
3482 | } | |
3483 | rcu_read_unlock(); | |
3484 | ||
3485 | return id_size; | |
3486 | } | |
3487 | EXPORT_SYMBOL(scsi_vpd_lun_id); | |
a8aa3978 HR |
3488 | |
3489 | /* | |
3490 | * scsi_vpd_tpg_id - return a target port group identifier | |
3491 | * @sdev: SCSI device | |
3492 | * | |
3493 | * Returns the Target Port Group identifier from the information | |
3494 | * froom VPD page 0x83 of the device. | |
3495 | * | |
3496 | * Returns the identifier or error on failure. | |
3497 | */ | |
3498 | int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id) | |
3499 | { | |
ccf1e004 BVA |
3500 | const unsigned char *d; |
3501 | const struct scsi_vpd *vpd_pg83; | |
a8aa3978 HR |
3502 | int group_id = -EAGAIN, rel_port = -1; |
3503 | ||
3504 | rcu_read_lock(); | |
3505 | vpd_pg83 = rcu_dereference(sdev->vpd_pg83); | |
3506 | if (!vpd_pg83) { | |
3507 | rcu_read_unlock(); | |
3508 | return -ENXIO; | |
3509 | } | |
3510 | ||
ccf1e004 BVA |
3511 | d = vpd_pg83->data + 4; |
3512 | while (d < vpd_pg83->data + vpd_pg83->len) { | |
a8aa3978 HR |
3513 | switch (d[1] & 0xf) { |
3514 | case 0x4: | |
3515 | /* Relative target port */ | |
3516 | rel_port = get_unaligned_be16(&d[6]); | |
3517 | break; | |
3518 | case 0x5: | |
3519 | /* Target port group */ | |
3520 | group_id = get_unaligned_be16(&d[6]); | |
3521 | break; | |
3522 | default: | |
3523 | break; | |
3524 | } | |
3525 | d += d[3] + 4; | |
3526 | } | |
3527 | rcu_read_unlock(); | |
3528 | ||
3529 | if (group_id >= 0 && rel_id && rel_port != -1) | |
3530 | *rel_id = rel_port; | |
3531 | ||
3532 | return group_id; | |
3533 | } | |
3534 | EXPORT_SYMBOL(scsi_vpd_tpg_id); |