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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 | 2 | /* |
d285203c CH |
3 | * Copyright (C) 1999 Eric Youngdale |
4 | * Copyright (C) 2014 Christoph Hellwig | |
1da177e4 LT |
5 | * |
6 | * SCSI queueing library. | |
7 | * Initial versions: Eric Youngdale (eric@andante.org). | |
8 | * Based upon conversations with large numbers | |
9 | * of people at Linux Expo. | |
10 | */ | |
11 | ||
12 | #include <linux/bio.h> | |
d3f46f39 | 13 | #include <linux/bitops.h> |
1da177e4 LT |
14 | #include <linux/blkdev.h> |
15 | #include <linux/completion.h> | |
16 | #include <linux/kernel.h> | |
09703660 | 17 | #include <linux/export.h> |
1da177e4 LT |
18 | #include <linux/init.h> |
19 | #include <linux/pci.h> | |
20 | #include <linux/delay.h> | |
faead26d | 21 | #include <linux/hardirq.h> |
c6132da1 | 22 | #include <linux/scatterlist.h> |
d285203c | 23 | #include <linux/blk-mq.h> |
fe45e630 | 24 | #include <linux/blk-integrity.h> |
f1569ff1 | 25 | #include <linux/ratelimit.h> |
a8aa3978 | 26 | #include <asm/unaligned.h> |
1da177e4 LT |
27 | |
28 | #include <scsi/scsi.h> | |
beb40487 | 29 | #include <scsi/scsi_cmnd.h> |
1da177e4 LT |
30 | #include <scsi/scsi_dbg.h> |
31 | #include <scsi/scsi_device.h> | |
32 | #include <scsi/scsi_driver.h> | |
33 | #include <scsi/scsi_eh.h> | |
34 | #include <scsi/scsi_host.h> | |
7aa686d3 | 35 | #include <scsi/scsi_transport.h> /* __scsi_init_queue() */ |
ee14c674 | 36 | #include <scsi/scsi_dh.h> |
1da177e4 | 37 | |
3b5382c4 CH |
38 | #include <trace/events/scsi.h> |
39 | ||
0eebd005 | 40 | #include "scsi_debugfs.h" |
1da177e4 LT |
41 | #include "scsi_priv.h" |
42 | #include "scsi_logging.h" | |
43 | ||
92524fa1 ML |
44 | /* |
45 | * Size of integrity metadata is usually small, 1 inline sg should | |
46 | * cover normal cases. | |
47 | */ | |
3e99b3b1 ML |
48 | #ifdef CONFIG_ARCH_NO_SG_CHAIN |
49 | #define SCSI_INLINE_PROT_SG_CNT 0 | |
50 | #define SCSI_INLINE_SG_CNT 0 | |
51 | #else | |
92524fa1 | 52 | #define SCSI_INLINE_PROT_SG_CNT 1 |
3dccdf53 | 53 | #define SCSI_INLINE_SG_CNT 2 |
3e99b3b1 | 54 | #endif |
3dccdf53 | 55 | |
0a6ac4ee | 56 | static struct kmem_cache *scsi_sense_cache; |
0a6ac4ee | 57 | static DEFINE_MUTEX(scsi_sense_cache_mutex); |
1da177e4 | 58 | |
a45a1f36 BVA |
59 | static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd); |
60 | ||
0a6ac4ee CH |
61 | int scsi_init_sense_cache(struct Scsi_Host *shost) |
62 | { | |
0a6ac4ee CH |
63 | int ret = 0; |
64 | ||
f9b0530f | 65 | mutex_lock(&scsi_sense_cache_mutex); |
aaff5eba | 66 | if (!scsi_sense_cache) { |
0a6ac4ee | 67 | scsi_sense_cache = |
0afe76e8 DW |
68 | kmem_cache_create_usercopy("scsi_sense_cache", |
69 | SCSI_SENSE_BUFFERSIZE, 0, SLAB_HWCACHE_ALIGN, | |
70 | 0, SCSI_SENSE_BUFFERSIZE, NULL); | |
0a6ac4ee CH |
71 | if (!scsi_sense_cache) |
72 | ret = -ENOMEM; | |
73 | } | |
0a6ac4ee CH |
74 | mutex_unlock(&scsi_sense_cache_mutex); |
75 | return ret; | |
76 | } | |
6f9a35e2 | 77 | |
de3e8bf3 CH |
78 | static void |
79 | scsi_set_blocked(struct scsi_cmnd *cmd, int reason) | |
1da177e4 LT |
80 | { |
81 | struct Scsi_Host *host = cmd->device->host; | |
82 | struct scsi_device *device = cmd->device; | |
f0c0a376 | 83 | struct scsi_target *starget = scsi_target(device); |
1da177e4 LT |
84 | |
85 | /* | |
d8c37e7b | 86 | * Set the appropriate busy bit for the device/host. |
1da177e4 LT |
87 | * |
88 | * If the host/device isn't busy, assume that something actually | |
89 | * completed, and that we should be able to queue a command now. | |
90 | * | |
91 | * Note that the prior mid-layer assumption that any host could | |
92 | * always queue at least one command is now broken. The mid-layer | |
93 | * will implement a user specifiable stall (see | |
94 | * scsi_host.max_host_blocked and scsi_device.max_device_blocked) | |
95 | * if a command is requeued with no other commands outstanding | |
96 | * either for the device or for the host. | |
97 | */ | |
f0c0a376 MC |
98 | switch (reason) { |
99 | case SCSI_MLQUEUE_HOST_BUSY: | |
cd9070c9 | 100 | atomic_set(&host->host_blocked, host->max_host_blocked); |
f0c0a376 MC |
101 | break; |
102 | case SCSI_MLQUEUE_DEVICE_BUSY: | |
573e5913 | 103 | case SCSI_MLQUEUE_EH_RETRY: |
cd9070c9 CH |
104 | atomic_set(&device->device_blocked, |
105 | device->max_device_blocked); | |
f0c0a376 MC |
106 | break; |
107 | case SCSI_MLQUEUE_TARGET_BUSY: | |
cd9070c9 CH |
108 | atomic_set(&starget->target_blocked, |
109 | starget->max_target_blocked); | |
f0c0a376 MC |
110 | break; |
111 | } | |
de3e8bf3 CH |
112 | } |
113 | ||
54249306 | 114 | static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd, unsigned long msecs) |
d285203c | 115 | { |
aa8e25e5 BVA |
116 | struct request *rq = scsi_cmd_to_rq(cmd); |
117 | ||
118 | if (rq->rq_flags & RQF_DONTPREP) { | |
119 | rq->rq_flags &= ~RQF_DONTPREP; | |
a45a1f36 BVA |
120 | scsi_mq_uninit_cmd(cmd); |
121 | } else { | |
122 | WARN_ON_ONCE(true); | |
123 | } | |
54249306 | 124 | |
8b566edb BVA |
125 | blk_mq_requeue_request(rq, false); |
126 | if (!scsi_host_in_recovery(cmd->device->host)) | |
54249306 | 127 | blk_mq_delay_kick_requeue_list(rq->q, msecs); |
d285203c CH |
128 | } |
129 | ||
de3e8bf3 CH |
130 | /** |
131 | * __scsi_queue_insert - private queue insertion | |
132 | * @cmd: The SCSI command being requeued | |
133 | * @reason: The reason for the requeue | |
134 | * @unbusy: Whether the queue should be unbusied | |
135 | * | |
136 | * This is a private queue insertion. The public interface | |
137 | * scsi_queue_insert() always assumes the queue should be unbusied | |
138 | * because it's always called before the completion. This function is | |
139 | * for a requeue after completion, which should only occur in this | |
140 | * file. | |
141 | */ | |
08640e81 | 142 | static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy) |
de3e8bf3 CH |
143 | { |
144 | struct scsi_device *device = cmd->device; | |
de3e8bf3 CH |
145 | |
146 | SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd, | |
147 | "Inserting command %p into mlqueue\n", cmd)); | |
148 | ||
149 | scsi_set_blocked(cmd, reason); | |
1da177e4 | 150 | |
1da177e4 LT |
151 | /* |
152 | * Decrement the counters, since these commands are no longer | |
153 | * active on the host/device. | |
154 | */ | |
4f5299ac | 155 | if (unbusy) |
6eb045e0 | 156 | scsi_device_unbusy(device, cmd); |
1da177e4 LT |
157 | |
158 | /* | |
a1bf9d1d | 159 | * Requeue this command. It will go before all other commands |
b485462a BVA |
160 | * that are already in the queue. Schedule requeue work under |
161 | * lock such that the kblockd_schedule_work() call happens | |
6f8191fd | 162 | * before blk_mq_destroy_queue() finishes. |
a488e749 | 163 | */ |
644373a4 | 164 | cmd->result = 0; |
f664a3cc | 165 | |
8b566edb BVA |
166 | blk_mq_requeue_request(scsi_cmd_to_rq(cmd), |
167 | !scsi_host_in_recovery(cmd->device->host)); | |
1da177e4 LT |
168 | } |
169 | ||
ea941016 AA |
170 | /** |
171 | * scsi_queue_insert - Reinsert a command in the queue. | |
172 | * @cmd: command that we are adding to queue. | |
173 | * @reason: why we are inserting command to queue. | |
4f5299ac | 174 | * |
ea941016 AA |
175 | * We do this for one of two cases. Either the host is busy and it cannot accept |
176 | * any more commands for the time being, or the device returned QUEUE_FULL and | |
177 | * can accept no more commands. | |
4f5299ac | 178 | * |
ea941016 AA |
179 | * Context: This could be called either from an interrupt context or a normal |
180 | * process context. | |
4f5299ac | 181 | */ |
84feb166 | 182 | void scsi_queue_insert(struct scsi_cmnd *cmd, int reason) |
4f5299ac | 183 | { |
08640e81 | 184 | __scsi_queue_insert(cmd, reason, true); |
4f5299ac | 185 | } |
e8064021 | 186 | |
76aaf87b | 187 | /** |
d0949565 MC |
188 | * scsi_execute_cmd - insert request and wait for the result |
189 | * @sdev: scsi_device | |
76aaf87b | 190 | * @cmd: scsi command |
d0949565 | 191 | * @opf: block layer request cmd_flags |
76aaf87b CH |
192 | * @buffer: data buffer |
193 | * @bufflen: len of buffer | |
422969bb | 194 | * @timeout: request timeout in HZ |
76aaf87b | 195 | * @retries: number of times to retry request |
d0949565 | 196 | * @args: Optional args. See struct definition for field descriptions |
76aaf87b | 197 | * |
17d5363b CH |
198 | * Returns the scsi_cmnd result field if a command was executed, or a negative |
199 | * Linux error code if we didn't get that far. | |
76aaf87b | 200 | */ |
d0949565 MC |
201 | int scsi_execute_cmd(struct scsi_device *sdev, const unsigned char *cmd, |
202 | blk_opf_t opf, void *buffer, unsigned int bufflen, | |
203 | int timeout, int retries, | |
204 | const struct scsi_exec_args *args) | |
39216033 | 205 | { |
d0949565 | 206 | static const struct scsi_exec_args default_args; |
39216033 | 207 | struct request *req; |
ce70fd9a | 208 | struct scsi_cmnd *scmd; |
ced202f7 | 209 | int ret; |
39216033 | 210 | |
d0949565 MC |
211 | if (!args) |
212 | args = &default_args; | |
213 | else if (WARN_ON_ONCE(args->sense && | |
214 | args->sense_len != SCSI_SENSE_BUFFERSIZE)) | |
215 | return -EINVAL; | |
216 | ||
217 | req = scsi_alloc_request(sdev->request_queue, opf, args->req_flags); | |
a492f075 | 218 | if (IS_ERR(req)) |
ced202f7 | 219 | return PTR_ERR(req); |
39216033 | 220 | |
ced202f7 HR |
221 | if (bufflen) { |
222 | ret = blk_rq_map_kern(sdev->request_queue, req, | |
223 | buffer, bufflen, GFP_NOIO); | |
224 | if (ret) | |
225 | goto out; | |
226 | } | |
ce70fd9a CH |
227 | scmd = blk_mq_rq_to_pdu(req); |
228 | scmd->cmd_len = COMMAND_SIZE(cmd[0]); | |
229 | memcpy(scmd->cmnd, cmd, scmd->cmd_len); | |
6aded12b | 230 | scmd->allowed = retries; |
35cd2f55 | 231 | scmd->flags |= args->scmd_flags; |
39216033 | 232 | req->timeout = timeout; |
d0949565 | 233 | req->rq_flags |= RQF_QUIET; |
39216033 JB |
234 | |
235 | /* | |
236 | * head injection *required* here otherwise quiesce won't work | |
237 | */ | |
b84ba30b | 238 | blk_execute_rq(req, true); |
39216033 | 239 | |
bdb2b8ca AS |
240 | /* |
241 | * Some devices (USB mass-storage in particular) may transfer | |
242 | * garbage data together with a residue indicating that the data | |
243 | * is invalid. Prevent the garbage from being misinterpreted | |
244 | * and prevent security leaks by zeroing out the excess data. | |
245 | */ | |
a9a4ea11 CH |
246 | if (unlikely(scmd->resid_len > 0 && scmd->resid_len <= bufflen)) |
247 | memset(buffer + bufflen - scmd->resid_len, 0, scmd->resid_len); | |
bdb2b8ca | 248 | |
d0949565 MC |
249 | if (args->resid) |
250 | *args->resid = scmd->resid_len; | |
251 | if (args->sense) | |
252 | memcpy(args->sense, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE); | |
253 | if (args->sshdr) | |
5b794f98 | 254 | scsi_normalize_sense(scmd->sense_buffer, scmd->sense_len, |
d0949565 MC |
255 | args->sshdr); |
256 | ||
dbb4c84d | 257 | ret = scmd->result; |
39216033 | 258 | out: |
0bf6d96c | 259 | blk_mq_free_request(req); |
39216033 JB |
260 | |
261 | return ret; | |
262 | } | |
d0949565 | 263 | EXPORT_SYMBOL(scsi_execute_cmd); |
39216033 | 264 | |
3bd6f43f | 265 | /* |
6eb045e0 ML |
266 | * Wake up the error handler if necessary. Avoid as follows that the error |
267 | * handler is not woken up if host in-flight requests number == | |
268 | * shost->host_failed: use call_rcu() in scsi_eh_scmd_add() in combination | |
269 | * with an RCU read lock in this function to ensure that this function in | |
270 | * its entirety either finishes before scsi_eh_scmd_add() increases the | |
3bd6f43f BVA |
271 | * host_failed counter or that it notices the shost state change made by |
272 | * scsi_eh_scmd_add(). | |
273 | */ | |
6eb045e0 | 274 | static void scsi_dec_host_busy(struct Scsi_Host *shost, struct scsi_cmnd *cmd) |
1da177e4 | 275 | { |
1da177e4 LT |
276 | unsigned long flags; |
277 | ||
3bd6f43f | 278 | rcu_read_lock(); |
6eb045e0 | 279 | __clear_bit(SCMD_STATE_INFLIGHT, &cmd->state); |
3bd6f43f | 280 | if (unlikely(scsi_host_in_recovery(shost))) { |
74665016 | 281 | spin_lock_irqsave(shost->host_lock, flags); |
3bd6f43f BVA |
282 | if (shost->host_failed || shost->host_eh_scheduled) |
283 | scsi_eh_wakeup(shost); | |
74665016 CH |
284 | spin_unlock_irqrestore(shost->host_lock, flags); |
285 | } | |
3bd6f43f BVA |
286 | rcu_read_unlock(); |
287 | } | |
288 | ||
6eb045e0 | 289 | void scsi_device_unbusy(struct scsi_device *sdev, struct scsi_cmnd *cmd) |
3bd6f43f BVA |
290 | { |
291 | struct Scsi_Host *shost = sdev->host; | |
292 | struct scsi_target *starget = scsi_target(sdev); | |
293 | ||
6eb045e0 | 294 | scsi_dec_host_busy(shost, cmd); |
3bd6f43f BVA |
295 | |
296 | if (starget->can_queue > 0) | |
297 | atomic_dec(&starget->target_busy); | |
74665016 | 298 | |
020b0f0a | 299 | sbitmap_put(&sdev->budget_map, cmd->budget_token); |
2a5a24aa | 300 | cmd->budget_token = -1; |
1da177e4 LT |
301 | } |
302 | ||
d460f624 BVA |
303 | /* |
304 | * Kick the queue of SCSI device @sdev if @sdev != current_sdev. Called with | |
305 | * interrupts disabled. | |
306 | */ | |
307 | static void scsi_kick_sdev_queue(struct scsi_device *sdev, void *data) | |
308 | { | |
309 | struct scsi_device *current_sdev = data; | |
310 | ||
311 | if (sdev != current_sdev) | |
312 | blk_mq_run_hw_queues(sdev->request_queue, true); | |
313 | } | |
314 | ||
1da177e4 LT |
315 | /* |
316 | * Called for single_lun devices on IO completion. Clear starget_sdev_user, | |
317 | * and call blk_run_queue for all the scsi_devices on the target - | |
318 | * including current_sdev first. | |
319 | * | |
320 | * Called with *no* scsi locks held. | |
321 | */ | |
322 | static void scsi_single_lun_run(struct scsi_device *current_sdev) | |
323 | { | |
324 | struct Scsi_Host *shost = current_sdev->host; | |
1da177e4 LT |
325 | struct scsi_target *starget = scsi_target(current_sdev); |
326 | unsigned long flags; | |
327 | ||
328 | spin_lock_irqsave(shost->host_lock, flags); | |
329 | starget->starget_sdev_user = NULL; | |
330 | spin_unlock_irqrestore(shost->host_lock, flags); | |
331 | ||
332 | /* | |
333 | * Call blk_run_queue for all LUNs on the target, starting with | |
334 | * current_sdev. We race with others (to set starget_sdev_user), | |
335 | * but in most cases, we will be first. Ideally, each LU on the | |
336 | * target would get some limited time or requests on the target. | |
337 | */ | |
65a558f6 BVA |
338 | blk_mq_run_hw_queues(current_sdev->request_queue, |
339 | shost->queuecommand_may_block); | |
1da177e4 LT |
340 | |
341 | spin_lock_irqsave(shost->host_lock, flags); | |
d460f624 BVA |
342 | if (!starget->starget_sdev_user) |
343 | __starget_for_each_device(starget, current_sdev, | |
344 | scsi_kick_sdev_queue); | |
1da177e4 LT |
345 | spin_unlock_irqrestore(shost->host_lock, flags); |
346 | } | |
347 | ||
cd9070c9 | 348 | static inline bool scsi_device_is_busy(struct scsi_device *sdev) |
9d112517 | 349 | { |
8278807a | 350 | if (scsi_device_busy(sdev) >= sdev->queue_depth) |
cd9070c9 CH |
351 | return true; |
352 | if (atomic_read(&sdev->device_blocked) > 0) | |
353 | return true; | |
354 | return false; | |
9d112517 KU |
355 | } |
356 | ||
cd9070c9 | 357 | static inline bool scsi_target_is_busy(struct scsi_target *starget) |
f0c0a376 | 358 | { |
2ccbb008 CH |
359 | if (starget->can_queue > 0) { |
360 | if (atomic_read(&starget->target_busy) >= starget->can_queue) | |
361 | return true; | |
362 | if (atomic_read(&starget->target_blocked) > 0) | |
363 | return true; | |
364 | } | |
cd9070c9 | 365 | return false; |
f0c0a376 MC |
366 | } |
367 | ||
cd9070c9 | 368 | static inline bool scsi_host_is_busy(struct Scsi_Host *shost) |
9d112517 | 369 | { |
cd9070c9 CH |
370 | if (atomic_read(&shost->host_blocked) > 0) |
371 | return true; | |
372 | if (shost->host_self_blocked) | |
373 | return true; | |
374 | return false; | |
9d112517 KU |
375 | } |
376 | ||
21a05df5 | 377 | static void scsi_starved_list_run(struct Scsi_Host *shost) |
1da177e4 | 378 | { |
2a3a59e5 | 379 | LIST_HEAD(starved_list); |
21a05df5 | 380 | struct scsi_device *sdev; |
1da177e4 LT |
381 | unsigned long flags; |
382 | ||
1da177e4 | 383 | spin_lock_irqsave(shost->host_lock, flags); |
2a3a59e5 MC |
384 | list_splice_init(&shost->starved_list, &starved_list); |
385 | ||
386 | while (!list_empty(&starved_list)) { | |
e2eb7244 JB |
387 | struct request_queue *slq; |
388 | ||
1da177e4 LT |
389 | /* |
390 | * As long as shost is accepting commands and we have | |
391 | * starved queues, call blk_run_queue. scsi_request_fn | |
392 | * drops the queue_lock and can add us back to the | |
393 | * starved_list. | |
394 | * | |
395 | * host_lock protects the starved_list and starved_entry. | |
396 | * scsi_request_fn must get the host_lock before checking | |
397 | * or modifying starved_list or starved_entry. | |
398 | */ | |
2a3a59e5 | 399 | if (scsi_host_is_busy(shost)) |
f0c0a376 | 400 | break; |
f0c0a376 | 401 | |
2a3a59e5 MC |
402 | sdev = list_entry(starved_list.next, |
403 | struct scsi_device, starved_entry); | |
404 | list_del_init(&sdev->starved_entry); | |
f0c0a376 MC |
405 | if (scsi_target_is_busy(scsi_target(sdev))) { |
406 | list_move_tail(&sdev->starved_entry, | |
407 | &shost->starved_list); | |
408 | continue; | |
409 | } | |
410 | ||
e2eb7244 JB |
411 | /* |
412 | * Once we drop the host lock, a racing scsi_remove_device() | |
413 | * call may remove the sdev from the starved list and destroy | |
414 | * it and the queue. Mitigate by taking a reference to the | |
415 | * queue and never touching the sdev again after we drop the | |
416 | * host lock. Note: if __scsi_remove_device() invokes | |
6f8191fd | 417 | * blk_mq_destroy_queue() before the queue is run from this |
e2eb7244 | 418 | * function then blk_run_queue() will return immediately since |
6f8191fd | 419 | * blk_mq_destroy_queue() marks the queue with QUEUE_FLAG_DYING. |
e2eb7244 JB |
420 | */ |
421 | slq = sdev->request_queue; | |
422 | if (!blk_get_queue(slq)) | |
423 | continue; | |
424 | spin_unlock_irqrestore(shost->host_lock, flags); | |
425 | ||
b5ca9acf | 426 | blk_mq_run_hw_queues(slq, false); |
e2eb7244 JB |
427 | blk_put_queue(slq); |
428 | ||
429 | spin_lock_irqsave(shost->host_lock, flags); | |
1da177e4 | 430 | } |
2a3a59e5 MC |
431 | /* put any unprocessed entries back */ |
432 | list_splice(&starved_list, &shost->starved_list); | |
1da177e4 | 433 | spin_unlock_irqrestore(shost->host_lock, flags); |
21a05df5 CH |
434 | } |
435 | ||
ea941016 AA |
436 | /** |
437 | * scsi_run_queue - Select a proper request queue to serve next. | |
438 | * @q: last request's queue | |
21a05df5 | 439 | * |
ea941016 | 440 | * The previous command was completely finished, start a new one if possible. |
21a05df5 CH |
441 | */ |
442 | static void scsi_run_queue(struct request_queue *q) | |
443 | { | |
444 | struct scsi_device *sdev = q->queuedata; | |
445 | ||
446 | if (scsi_target(sdev)->single_lun) | |
447 | scsi_single_lun_run(sdev); | |
448 | if (!list_empty(&sdev->host->starved_list)) | |
449 | scsi_starved_list_run(sdev->host); | |
1da177e4 | 450 | |
d42e2e34 | 451 | /* Note: blk_mq_kick_requeue_list() runs the queue asynchronously. */ |
8b566edb | 452 | blk_mq_kick_requeue_list(q); |
1da177e4 LT |
453 | } |
454 | ||
9937a5e2 JA |
455 | void scsi_requeue_run_queue(struct work_struct *work) |
456 | { | |
457 | struct scsi_device *sdev; | |
458 | struct request_queue *q; | |
459 | ||
460 | sdev = container_of(work, struct scsi_device, requeue_work); | |
461 | q = sdev->request_queue; | |
462 | scsi_run_queue(q); | |
463 | } | |
464 | ||
1da177e4 LT |
465 | void scsi_run_host_queues(struct Scsi_Host *shost) |
466 | { | |
467 | struct scsi_device *sdev; | |
468 | ||
469 | shost_for_each_device(sdev, shost) | |
470 | scsi_run_queue(sdev->request_queue); | |
471 | } | |
472 | ||
d285203c CH |
473 | static void scsi_uninit_cmd(struct scsi_cmnd *cmd) |
474 | { | |
aa8e25e5 | 475 | if (!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd))) { |
d285203c CH |
476 | struct scsi_driver *drv = scsi_cmd_to_driver(cmd); |
477 | ||
478 | if (drv->uninit_command) | |
479 | drv->uninit_command(cmd); | |
480 | } | |
481 | } | |
482 | ||
7007e9dd | 483 | void scsi_free_sgtables(struct scsi_cmnd *cmd) |
d285203c CH |
484 | { |
485 | if (cmd->sdb.table.nents) | |
3dccdf53 ML |
486 | sg_free_table_chained(&cmd->sdb.table, |
487 | SCSI_INLINE_SG_CNT); | |
d285203c | 488 | if (scsi_prot_sg_count(cmd)) |
92524fa1 ML |
489 | sg_free_table_chained(&cmd->prot_sdb->table, |
490 | SCSI_INLINE_PROT_SG_CNT); | |
d285203c | 491 | } |
7007e9dd | 492 | EXPORT_SYMBOL_GPL(scsi_free_sgtables); |
d285203c CH |
493 | |
494 | static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) | |
495 | { | |
20a66f2b | 496 | scsi_free_sgtables(cmd); |
d285203c | 497 | scsi_uninit_cmd(cmd); |
d285203c CH |
498 | } |
499 | ||
3f0dcfbc ML |
500 | static void scsi_run_queue_async(struct scsi_device *sdev) |
501 | { | |
8b566edb BVA |
502 | if (scsi_host_in_recovery(sdev->host)) |
503 | return; | |
504 | ||
3f0dcfbc | 505 | if (scsi_target(sdev)->single_lun || |
ed5dd6a6 | 506 | !list_empty(&sdev->host->starved_list)) { |
3f0dcfbc | 507 | kblockd_schedule_work(&sdev->requeue_work); |
ed5dd6a6 ML |
508 | } else { |
509 | /* | |
510 | * smp_mb() present in sbitmap_queue_clear() or implied in | |
511 | * .end_io is for ordering writing .device_busy in | |
512 | * scsi_device_unbusy() and reading sdev->restarts. | |
513 | */ | |
514 | int old = atomic_read(&sdev->restarts); | |
515 | ||
516 | /* | |
517 | * ->restarts has to be kept as non-zero if new budget | |
518 | * contention occurs. | |
519 | * | |
520 | * No need to run queue when either another re-run | |
521 | * queue wins in updating ->restarts or a new budget | |
522 | * contention occurs. | |
523 | */ | |
524 | if (old && atomic_cmpxchg(&sdev->restarts, old, 0) == old) | |
525 | blk_mq_run_hw_queues(sdev->request_queue, true); | |
526 | } | |
3f0dcfbc ML |
527 | } |
528 | ||
7e63b5a4 | 529 | /* Returns false when no more bytes to process, true if there are more */ |
2a842aca | 530 | static bool scsi_end_request(struct request *req, blk_status_t error, |
ae3d56d8 | 531 | unsigned int bytes) |
f6d47e74 | 532 | { |
bed2213d | 533 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
f6d47e74 CH |
534 | struct scsi_device *sdev = cmd->device; |
535 | struct request_queue *q = sdev->request_queue; | |
f6d47e74 CH |
536 | |
537 | if (blk_update_request(req, error, bytes)) | |
538 | return true; | |
539 | ||
f3fa33ac | 540 | // XXX: |
f6d47e74 | 541 | if (blk_queue_add_random(q)) |
f3fa33ac | 542 | add_disk_randomness(req->q->disk); |
f6d47e74 | 543 | |
da6269da | 544 | if (!blk_rq_is_passthrough(req)) { |
64104f70 BVA |
545 | WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED)); |
546 | cmd->flags &= ~SCMD_INITIALIZED; | |
547 | } | |
548 | ||
db983f6e BVA |
549 | /* |
550 | * Calling rcu_barrier() is not necessary here because the | |
551 | * SCSI error handler guarantees that the function called by | |
552 | * call_rcu() has been called before scsi_end_request() is | |
553 | * called. | |
554 | */ | |
555 | destroy_rcu_head(&cmd->rcu); | |
556 | ||
f664a3cc JA |
557 | /* |
558 | * In the MQ case the command gets freed by __blk_mq_end_request, | |
559 | * so we have to do all cleanup that depends on it earlier. | |
560 | * | |
561 | * We also can't kick the queues from irq context, so we | |
562 | * will have to defer it to a workqueue. | |
563 | */ | |
564 | scsi_mq_uninit_cmd(cmd); | |
f81426a8 | 565 | |
a78b03bc JA |
566 | /* |
567 | * queue is still alive, so grab the ref for preventing it | |
568 | * from being cleaned up during running queue. | |
569 | */ | |
570 | percpu_ref_get(&q->q_usage_counter); | |
f81426a8 | 571 | |
f664a3cc | 572 | __blk_mq_end_request(req, error); |
d285203c | 573 | |
3f0dcfbc | 574 | scsi_run_queue_async(sdev); |
f6d47e74 | 575 | |
a78b03bc | 576 | percpu_ref_put(&q->q_usage_counter); |
f6d47e74 CH |
577 | return false; |
578 | } | |
579 | ||
0f7f6234 | 580 | /** |
a77b32d8 | 581 | * scsi_result_to_blk_status - translate a SCSI result code into blk_status_t |
0f7f6234 HR |
582 | * @result: scsi error code |
583 | * | |
7dfaae6a | 584 | * Translate a SCSI result code into a blk_status_t value. |
0f7f6234 | 585 | */ |
7dfaae6a | 586 | static blk_status_t scsi_result_to_blk_status(int result) |
63583cca | 587 | { |
36ebf1e2 MC |
588 | /* |
589 | * Check the scsi-ml byte first in case we converted a host or status | |
590 | * byte. | |
591 | */ | |
73432693 | 592 | switch (scsi_ml_byte(result)) { |
36ebf1e2 MC |
593 | case SCSIML_STAT_OK: |
594 | break; | |
595 | case SCSIML_STAT_RESV_CONFLICT: | |
7ba15083 | 596 | return BLK_STS_RESV_CONFLICT; |
36ebf1e2 MC |
597 | case SCSIML_STAT_NOSPC: |
598 | return BLK_STS_NOSPC; | |
599 | case SCSIML_STAT_MED_ERROR: | |
600 | return BLK_STS_MEDIUM; | |
601 | case SCSIML_STAT_TGT_FAILURE: | |
602 | return BLK_STS_TARGET; | |
390e2d1a NC |
603 | case SCSIML_STAT_DL_TIMEOUT: |
604 | return BLK_STS_DURATION_LIMIT; | |
36ebf1e2 MC |
605 | } |
606 | ||
2a842aca | 607 | switch (host_byte(result)) { |
f4abab3f | 608 | case DID_OK: |
a7479a84 | 609 | if (scsi_status_is_good(result)) |
f4abab3f BVA |
610 | return BLK_STS_OK; |
611 | return BLK_STS_IOERR; | |
63583cca | 612 | case DID_TRANSPORT_FAILFAST: |
962c8dcd | 613 | case DID_TRANSPORT_MARGINAL: |
2a842aca | 614 | return BLK_STS_TRANSPORT; |
63583cca | 615 | default: |
2a842aca | 616 | return BLK_STS_IOERR; |
63583cca | 617 | } |
63583cca HR |
618 | } |
619 | ||
79478bf9 CH |
620 | /** |
621 | * scsi_rq_err_bytes - determine number of bytes till the next failure boundary | |
622 | * @rq: request to examine | |
623 | * | |
624 | * Description: | |
625 | * A request could be merge of IOs which require different failure | |
626 | * handling. This function determines the number of bytes which | |
627 | * can be failed from the beginning of the request without | |
628 | * crossing into area which need to be retried further. | |
629 | * | |
630 | * Return: | |
631 | * The number of bytes to fail. | |
632 | */ | |
633 | static unsigned int scsi_rq_err_bytes(const struct request *rq) | |
634 | { | |
2599cac5 | 635 | blk_opf_t ff = rq->cmd_flags & REQ_FAILFAST_MASK; |
79478bf9 CH |
636 | unsigned int bytes = 0; |
637 | struct bio *bio; | |
638 | ||
639 | if (!(rq->rq_flags & RQF_MIXED_MERGE)) | |
640 | return blk_rq_bytes(rq); | |
641 | ||
642 | /* | |
643 | * Currently the only 'mixing' which can happen is between | |
644 | * different fastfail types. We can safely fail portions | |
645 | * which have all the failfast bits that the first one has - | |
646 | * the ones which are at least as eager to fail as the first | |
647 | * one. | |
648 | */ | |
649 | for (bio = rq->bio; bio; bio = bio->bi_next) { | |
650 | if ((bio->bi_opf & ff) != ff) | |
651 | break; | |
652 | bytes += bio->bi_iter.bi_size; | |
653 | } | |
654 | ||
655 | /* this could lead to infinite loop */ | |
656 | BUG_ON(blk_rq_bytes(rq) && !bytes); | |
657 | return bytes; | |
658 | } | |
659 | ||
2a242d59 MC |
660 | static bool scsi_cmd_runtime_exceeced(struct scsi_cmnd *cmd) |
661 | { | |
aa8e25e5 | 662 | struct request *req = scsi_cmd_to_rq(cmd); |
2a242d59 MC |
663 | unsigned long wait_for; |
664 | ||
665 | if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT) | |
666 | return false; | |
667 | ||
668 | wait_for = (cmd->allowed + 1) * req->timeout; | |
669 | if (time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) { | |
670 | scmd_printk(KERN_ERR, cmd, "timing out command, waited %lus\n", | |
671 | wait_for/HZ); | |
672 | return true; | |
673 | } | |
674 | return false; | |
675 | } | |
676 | ||
54249306 BB |
677 | /* |
678 | * When ALUA transition state is returned, reprep the cmd to | |
679 | * use the ALUA handler's transition timeout. Delay the reprep | |
680 | * 1 sec to avoid aggressive retries of the target in that | |
681 | * state. | |
682 | */ | |
683 | #define ALUA_TRANSITION_REPREP_DELAY 1000 | |
684 | ||
da32baea DG |
685 | /* Helper for scsi_io_completion() when special action required. */ |
686 | static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result) | |
1da177e4 | 687 | { |
aa8e25e5 | 688 | struct request *req = scsi_cmd_to_rq(cmd); |
da32baea | 689 | int level = 0; |
54249306 BB |
690 | enum {ACTION_FAIL, ACTION_REPREP, ACTION_DELAYED_REPREP, |
691 | ACTION_RETRY, ACTION_DELAYED_RETRY} action; | |
da32baea DG |
692 | struct scsi_sense_hdr sshdr; |
693 | bool sense_valid; | |
694 | bool sense_current = true; /* false implies "deferred sense" */ | |
695 | blk_status_t blk_stat; | |
1da177e4 | 696 | |
da32baea DG |
697 | sense_valid = scsi_command_normalize_sense(cmd, &sshdr); |
698 | if (sense_valid) | |
699 | sense_current = !scsi_sense_is_deferred(&sshdr); | |
03aba2f7 | 700 | |
7dfaae6a | 701 | blk_stat = scsi_result_to_blk_status(result); |
3e695f89 | 702 | |
b60af5b0 AS |
703 | if (host_byte(result) == DID_RESET) { |
704 | /* Third party bus reset or reset for error recovery | |
705 | * reasons. Just retry the command and see what | |
706 | * happens. | |
707 | */ | |
708 | action = ACTION_RETRY; | |
da32baea | 709 | } else if (sense_valid && sense_current) { |
1da177e4 LT |
710 | switch (sshdr.sense_key) { |
711 | case UNIT_ATTENTION: | |
712 | if (cmd->device->removable) { | |
03aba2f7 | 713 | /* Detected disc change. Set a bit |
1da177e4 LT |
714 | * and quietly refuse further access. |
715 | */ | |
716 | cmd->device->changed = 1; | |
b60af5b0 | 717 | action = ACTION_FAIL; |
1da177e4 | 718 | } else { |
03aba2f7 LT |
719 | /* Must have been a power glitch, or a |
720 | * bus reset. Could not have been a | |
721 | * media change, so we just retry the | |
b60af5b0 | 722 | * command and see what happens. |
03aba2f7 | 723 | */ |
b60af5b0 | 724 | action = ACTION_RETRY; |
1da177e4 LT |
725 | } |
726 | break; | |
727 | case ILLEGAL_REQUEST: | |
03aba2f7 LT |
728 | /* If we had an ILLEGAL REQUEST returned, then |
729 | * we may have performed an unsupported | |
730 | * command. The only thing this should be | |
731 | * would be a ten byte read where only a six | |
732 | * byte read was supported. Also, on a system | |
733 | * where READ CAPACITY failed, we may have | |
734 | * read past the end of the disk. | |
735 | */ | |
26a68019 JA |
736 | if ((cmd->device->use_10_for_rw && |
737 | sshdr.asc == 0x20 && sshdr.ascq == 0x00) && | |
1da177e4 LT |
738 | (cmd->cmnd[0] == READ_10 || |
739 | cmd->cmnd[0] == WRITE_10)) { | |
b60af5b0 | 740 | /* This will issue a new 6-byte command. */ |
1da177e4 | 741 | cmd->device->use_10_for_rw = 0; |
b60af5b0 | 742 | action = ACTION_REPREP; |
3e695f89 | 743 | } else if (sshdr.asc == 0x10) /* DIX */ { |
3e695f89 | 744 | action = ACTION_FAIL; |
da32baea | 745 | blk_stat = BLK_STS_PROTECTION; |
c98a0eb0 | 746 | /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */ |
5db44863 | 747 | } else if (sshdr.asc == 0x20 || sshdr.asc == 0x24) { |
c98a0eb0 | 748 | action = ACTION_FAIL; |
da32baea | 749 | blk_stat = BLK_STS_TARGET; |
b60af5b0 AS |
750 | } else |
751 | action = ACTION_FAIL; | |
752 | break; | |
511e44f4 | 753 | case ABORTED_COMMAND: |
126c0982 | 754 | action = ACTION_FAIL; |
e6c11dbb | 755 | if (sshdr.asc == 0x10) /* DIF */ |
da32baea | 756 | blk_stat = BLK_STS_PROTECTION; |
1da177e4 LT |
757 | break; |
758 | case NOT_READY: | |
03aba2f7 | 759 | /* If the device is in the process of becoming |
f3e93f73 | 760 | * ready, or has a temporary blockage, retry. |
1da177e4 | 761 | */ |
f3e93f73 JB |
762 | if (sshdr.asc == 0x04) { |
763 | switch (sshdr.ascq) { | |
764 | case 0x01: /* becoming ready */ | |
765 | case 0x04: /* format in progress */ | |
766 | case 0x05: /* rebuild in progress */ | |
767 | case 0x06: /* recalculation in progress */ | |
768 | case 0x07: /* operation in progress */ | |
769 | case 0x08: /* Long write in progress */ | |
770 | case 0x09: /* self test in progress */ | |
104739ac | 771 | case 0x11: /* notify (enable spinup) required */ |
d8705f11 | 772 | case 0x14: /* space allocation in progress */ |
e37c7d9a DG |
773 | case 0x1a: /* start stop unit in progress */ |
774 | case 0x1b: /* sanitize in progress */ | |
775 | case 0x1d: /* configuration in progress */ | |
776 | case 0x24: /* depopulation in progress */ | |
b60af5b0 | 777 | action = ACTION_DELAYED_RETRY; |
f3e93f73 | 778 | break; |
0d882320 | 779 | case 0x0a: /* ALUA state transition */ |
54249306 BB |
780 | action = ACTION_DELAYED_REPREP; |
781 | break; | |
3dbf6a54 | 782 | default: |
3dbf6a54 AS |
783 | action = ACTION_FAIL; |
784 | break; | |
f3e93f73 | 785 | } |
e6c11dbb | 786 | } else |
b60af5b0 | 787 | action = ACTION_FAIL; |
b60af5b0 | 788 | break; |
1da177e4 | 789 | case VOLUME_OVERFLOW: |
03aba2f7 | 790 | /* See SSC3rXX or current. */ |
b60af5b0 AS |
791 | action = ACTION_FAIL; |
792 | break; | |
d8f53b0a DLM |
793 | case DATA_PROTECT: |
794 | action = ACTION_FAIL; | |
795 | if ((sshdr.asc == 0x0C && sshdr.ascq == 0x12) || | |
796 | (sshdr.asc == 0x55 && | |
797 | (sshdr.ascq == 0x0E || sshdr.ascq == 0x0F))) { | |
798 | /* Insufficient zone resources */ | |
799 | blk_stat = BLK_STS_ZONE_OPEN_RESOURCE; | |
800 | } | |
801 | break; | |
390e2d1a NC |
802 | case COMPLETED: |
803 | fallthrough; | |
1da177e4 | 804 | default: |
b60af5b0 | 805 | action = ACTION_FAIL; |
1da177e4 LT |
806 | break; |
807 | } | |
e6c11dbb | 808 | } else |
b60af5b0 | 809 | action = ACTION_FAIL; |
b60af5b0 | 810 | |
2a242d59 | 811 | if (action != ACTION_FAIL && scsi_cmd_runtime_exceeced(cmd)) |
ee60b2c5 | 812 | action = ACTION_FAIL; |
ee60b2c5 | 813 | |
b60af5b0 AS |
814 | switch (action) { |
815 | case ACTION_FAIL: | |
816 | /* Give up and fail the remainder of the request */ | |
e8064021 | 817 | if (!(req->rq_flags & RQF_QUIET)) { |
f1569ff1 HR |
818 | static DEFINE_RATELIMIT_STATE(_rs, |
819 | DEFAULT_RATELIMIT_INTERVAL, | |
820 | DEFAULT_RATELIMIT_BURST); | |
821 | ||
822 | if (unlikely(scsi_logging_level)) | |
da32baea DG |
823 | level = |
824 | SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, | |
825 | SCSI_LOG_MLCOMPLETE_BITS); | |
f1569ff1 HR |
826 | |
827 | /* | |
828 | * if logging is enabled the failure will be printed | |
829 | * in scsi_log_completion(), so avoid duplicate messages | |
830 | */ | |
831 | if (!level && __ratelimit(&_rs)) { | |
832 | scsi_print_result(cmd, NULL, FAILED); | |
464a00c9 | 833 | if (sense_valid) |
f1569ff1 HR |
834 | scsi_print_sense(cmd); |
835 | scsi_print_command(cmd); | |
836 | } | |
3173d8c3 | 837 | } |
79478bf9 | 838 | if (!scsi_end_request(req, blk_stat, scsi_rq_err_bytes(req))) |
f6d47e74 | 839 | return; |
df561f66 | 840 | fallthrough; |
b60af5b0 | 841 | case ACTION_REPREP: |
54249306 BB |
842 | scsi_mq_requeue_cmd(cmd, 0); |
843 | break; | |
844 | case ACTION_DELAYED_REPREP: | |
845 | scsi_mq_requeue_cmd(cmd, ALUA_TRANSITION_REPREP_DELAY); | |
b60af5b0 AS |
846 | break; |
847 | case ACTION_RETRY: | |
848 | /* Retry the same command immediately */ | |
08640e81 | 849 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY, false); |
b60af5b0 AS |
850 | break; |
851 | case ACTION_DELAYED_RETRY: | |
852 | /* Retry the same command after a delay */ | |
08640e81 | 853 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, false); |
b60af5b0 | 854 | break; |
1da177e4 LT |
855 | } |
856 | } | |
1da177e4 | 857 | |
ab831084 DG |
858 | /* |
859 | * Helper for scsi_io_completion() when cmd->result is non-zero. Returns a | |
860 | * new result that may suppress further error checking. Also modifies | |
861 | * *blk_statp in some cases. | |
862 | */ | |
863 | static int scsi_io_completion_nz_result(struct scsi_cmnd *cmd, int result, | |
864 | blk_status_t *blk_statp) | |
865 | { | |
866 | bool sense_valid; | |
867 | bool sense_current = true; /* false implies "deferred sense" */ | |
aa8e25e5 | 868 | struct request *req = scsi_cmd_to_rq(cmd); |
ab831084 DG |
869 | struct scsi_sense_hdr sshdr; |
870 | ||
871 | sense_valid = scsi_command_normalize_sense(cmd, &sshdr); | |
872 | if (sense_valid) | |
873 | sense_current = !scsi_sense_is_deferred(&sshdr); | |
874 | ||
875 | if (blk_rq_is_passthrough(req)) { | |
876 | if (sense_valid) { | |
877 | /* | |
878 | * SG_IO wants current and deferred errors | |
879 | */ | |
5b794f98 CH |
880 | cmd->sense_len = min(8 + cmd->sense_buffer[7], |
881 | SCSI_SENSE_BUFFERSIZE); | |
ab831084 DG |
882 | } |
883 | if (sense_current) | |
7dfaae6a | 884 | *blk_statp = scsi_result_to_blk_status(result); |
ab831084 DG |
885 | } else if (blk_rq_bytes(req) == 0 && sense_current) { |
886 | /* | |
887 | * Flush commands do not transfers any data, and thus cannot use | |
888 | * good_bytes != blk_rq_bytes(req) as the signal for an error. | |
889 | * This sets *blk_statp explicitly for the problem case. | |
890 | */ | |
7dfaae6a | 891 | *blk_statp = scsi_result_to_blk_status(result); |
ab831084 DG |
892 | } |
893 | /* | |
894 | * Recovered errors need reporting, but they're always treated as | |
895 | * success, so fiddle the result code here. For passthrough requests | |
896 | * we already took a copy of the original into sreq->result which | |
897 | * is what gets returned to the user | |
898 | */ | |
899 | if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) { | |
900 | bool do_print = true; | |
901 | /* | |
902 | * if ATA PASS-THROUGH INFORMATION AVAILABLE [0x0, 0x1d] | |
903 | * skip print since caller wants ATA registers. Only occurs | |
904 | * on SCSI ATA PASS_THROUGH commands when CK_COND=1 | |
905 | */ | |
906 | if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d)) | |
907 | do_print = false; | |
908 | else if (req->rq_flags & RQF_QUIET) | |
909 | do_print = false; | |
910 | if (do_print) | |
911 | scsi_print_sense(cmd); | |
912 | result = 0; | |
913 | /* for passthrough, *blk_statp may be set */ | |
914 | *blk_statp = BLK_STS_OK; | |
915 | } | |
916 | /* | |
917 | * Another corner case: the SCSI status byte is non-zero but 'good'. | |
918 | * Example: PRE-FETCH command returns SAM_STAT_CONDITION_MET when | |
919 | * it is able to fit nominated LBs in its cache (and SAM_STAT_GOOD | |
920 | * if it can't fit). Treat SAM_STAT_CONDITION_MET and the related | |
921 | * intermediate statuses (both obsolete in SAM-4) as good. | |
922 | */ | |
3d45cefc | 923 | if ((result & 0xff) && scsi_status_is_good(result)) { |
ab831084 DG |
924 | result = 0; |
925 | *blk_statp = BLK_STS_OK; | |
926 | } | |
927 | return result; | |
928 | } | |
929 | ||
ea941016 AA |
930 | /** |
931 | * scsi_io_completion - Completion processing for SCSI commands. | |
932 | * @cmd: command that is finished. | |
933 | * @good_bytes: number of processed bytes. | |
1da177e4 | 934 | * |
ea941016 AA |
935 | * We will finish off the specified number of sectors. If we are done, the |
936 | * command block will be released and the queue function will be goosed. If we | |
937 | * are not done then we have to figure out what to do next: | |
1da177e4 | 938 | * |
54249306 | 939 | * a) We can call scsi_mq_requeue_cmd(). The request will be |
ea941016 AA |
940 | * unprepared and put back on the queue. Then a new command will |
941 | * be created for it. This should be used if we made forward | |
942 | * progress, or if we want to switch from READ(10) to READ(6) for | |
943 | * example. | |
1da177e4 | 944 | * |
ea941016 AA |
945 | * b) We can call scsi_io_completion_action(). The request will be |
946 | * put back on the queue and retried using the same command as | |
947 | * before, possibly after a delay. | |
b60af5b0 | 948 | * |
ea941016 AA |
949 | * c) We can call scsi_end_request() with blk_stat other than |
950 | * BLK_STS_OK, to fail the remainder of the request. | |
1da177e4 | 951 | */ |
03aba2f7 | 952 | void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) |
1da177e4 LT |
953 | { |
954 | int result = cmd->result; | |
aa8e25e5 | 955 | struct request *req = scsi_cmd_to_rq(cmd); |
1f7cbb8e | 956 | blk_status_t blk_stat = BLK_STS_OK; |
1da177e4 | 957 | |
0d437906 | 958 | if (unlikely(result)) /* a nz result may or may not be an error */ |
ab831084 | 959 | result = scsi_io_completion_nz_result(cmd, result, &blk_stat); |
631c228c | 960 | |
1da177e4 LT |
961 | /* |
962 | * Next deal with any sectors which we were able to correctly | |
963 | * handle. | |
964 | */ | |
91921e01 HR |
965 | SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, cmd, |
966 | "%u sectors total, %d bytes done.\n", | |
967 | blk_rq_sectors(req), good_bytes)); | |
d6b0c537 | 968 | |
a9bddd74 | 969 | /* |
ea941016 | 970 | * Failed, zero length commands always need to drop down |
1f7cbb8e | 971 | * to retry code. Fast path should return in this block. |
d6b0c537 | 972 | */ |
0d437906 | 973 | if (likely(blk_rq_bytes(req) > 0 || blk_stat == BLK_STS_OK)) { |
ae3d56d8 | 974 | if (likely(!scsi_end_request(req, blk_stat, good_bytes))) |
1f7cbb8e DG |
975 | return; /* no bytes remaining */ |
976 | } | |
bc85dc50 | 977 | |
0d437906 DG |
978 | /* Kill remainder if no retries. */ |
979 | if (unlikely(blk_stat && scsi_noretry_cmd(cmd))) { | |
ae3d56d8 | 980 | if (scsi_end_request(req, blk_stat, blk_rq_bytes(req))) |
8e1695a0 DG |
981 | WARN_ONCE(true, |
982 | "Bytes remaining after failed, no-retry command"); | |
f6d47e74 | 983 | return; |
bc85dc50 CH |
984 | } |
985 | ||
986 | /* | |
987 | * If there had been no error, but we have leftover bytes in the | |
e9076e7f | 988 | * request just queue the command up again. |
d6b0c537 | 989 | */ |
0d437906 | 990 | if (likely(result == 0)) |
54249306 | 991 | scsi_mq_requeue_cmd(cmd, 0); |
4ae61c68 | 992 | else |
da32baea | 993 | scsi_io_completion_action(cmd, result); |
1da177e4 | 994 | } |
1da177e4 | 995 | |
cc97923a CH |
996 | static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev, |
997 | struct request *rq) | |
1da177e4 | 998 | { |
cc97923a CH |
999 | return sdev->dma_drain_len && blk_rq_is_passthrough(rq) && |
1000 | !op_is_write(req_op(rq)) && | |
1001 | sdev->host->hostt->dma_need_drain(rq); | |
1da177e4 | 1002 | } |
6f9a35e2 | 1003 | |
ea941016 | 1004 | /** |
76fc0df9 BVA |
1005 | * scsi_alloc_sgtables - Allocate and initialize data and integrity scatterlists |
1006 | * @cmd: SCSI command data structure to initialize. | |
1007 | * | |
1008 | * Initializes @cmd->sdb and also @cmd->prot_sdb if data integrity is enabled | |
1009 | * for @cmd. | |
6f9a35e2 | 1010 | * |
ea941016 AA |
1011 | * Returns: |
1012 | * * BLK_STS_OK - on success | |
1013 | * * BLK_STS_RESOURCE - if the failure is retryable | |
1014 | * * BLK_STS_IOERR - if the failure is fatal | |
6f9a35e2 | 1015 | */ |
7007e9dd | 1016 | blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd) |
6f9a35e2 | 1017 | { |
cc97923a | 1018 | struct scsi_device *sdev = cmd->device; |
aa8e25e5 | 1019 | struct request *rq = scsi_cmd_to_rq(cmd); |
cc97923a CH |
1020 | unsigned short nr_segs = blk_rq_nr_phys_segments(rq); |
1021 | struct scatterlist *last_sg = NULL; | |
159b2cbf | 1022 | blk_status_t ret; |
cc97923a | 1023 | bool need_drain = scsi_cmd_needs_dma_drain(sdev, rq); |
0475bd6c | 1024 | int count; |
13f05c8d | 1025 | |
cc97923a | 1026 | if (WARN_ON_ONCE(!nr_segs)) |
159b2cbf | 1027 | return BLK_STS_IOERR; |
635d98b1 | 1028 | |
cc97923a CH |
1029 | /* |
1030 | * Make sure there is space for the drain. The driver must adjust | |
1031 | * max_hw_segments to be prepared for this. | |
1032 | */ | |
1033 | if (need_drain) | |
1034 | nr_segs++; | |
1035 | ||
0475bd6c CH |
1036 | /* |
1037 | * If sg table allocation fails, requeue request later. | |
1038 | */ | |
cc97923a CH |
1039 | if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, nr_segs, |
1040 | cmd->sdb.table.sgl, SCSI_INLINE_SG_CNT))) | |
0475bd6c CH |
1041 | return BLK_STS_RESOURCE; |
1042 | ||
1043 | /* | |
1044 | * Next, walk the list, and fill in the addresses and sizes of | |
1045 | * each segment. | |
1046 | */ | |
cc97923a CH |
1047 | count = __blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl, &last_sg); |
1048 | ||
bdf8710d CH |
1049 | if (blk_rq_bytes(rq) & rq->q->dma_pad_mask) { |
1050 | unsigned int pad_len = | |
1051 | (rq->q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1; | |
1052 | ||
1053 | last_sg->length += pad_len; | |
1054 | cmd->extra_len += pad_len; | |
1055 | } | |
1056 | ||
cc97923a CH |
1057 | if (need_drain) { |
1058 | sg_unmark_end(last_sg); | |
1059 | last_sg = sg_next(last_sg); | |
1060 | sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len); | |
1061 | sg_mark_end(last_sg); | |
1062 | ||
bdf8710d | 1063 | cmd->extra_len += sdev->dma_drain_len; |
cc97923a CH |
1064 | count++; |
1065 | } | |
1066 | ||
0475bd6c CH |
1067 | BUG_ON(count > cmd->sdb.table.nents); |
1068 | cmd->sdb.table.nents = count; | |
1069 | cmd->sdb.length = blk_rq_payload_bytes(rq); | |
6f9a35e2 | 1070 | |
13f05c8d | 1071 | if (blk_integrity_rq(rq)) { |
7027ad72 | 1072 | struct scsi_data_buffer *prot_sdb = cmd->prot_sdb; |
0475bd6c | 1073 | int ivecs; |
7027ad72 | 1074 | |
14784565 | 1075 | if (WARN_ON_ONCE(!prot_sdb)) { |
91724c20 EM |
1076 | /* |
1077 | * This can happen if someone (e.g. multipath) | |
1078 | * queues a command to a device on an adapter | |
1079 | * that does not support DIX. | |
1080 | */ | |
159b2cbf | 1081 | ret = BLK_STS_IOERR; |
14784565 | 1082 | goto out_free_sgtables; |
91724c20 EM |
1083 | } |
1084 | ||
13f05c8d | 1085 | ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio); |
7027ad72 | 1086 | |
001d63be | 1087 | if (sg_alloc_table_chained(&prot_sdb->table, ivecs, |
4635873c | 1088 | prot_sdb->table.sgl, |
92524fa1 | 1089 | SCSI_INLINE_PROT_SG_CNT)) { |
159b2cbf | 1090 | ret = BLK_STS_RESOURCE; |
14784565 | 1091 | goto out_free_sgtables; |
7027ad72 MP |
1092 | } |
1093 | ||
13f05c8d | 1094 | count = blk_rq_map_integrity_sg(rq->q, rq->bio, |
7027ad72 | 1095 | prot_sdb->table.sgl); |
6f1d8a53 IS |
1096 | BUG_ON(count > ivecs); |
1097 | BUG_ON(count > queue_max_integrity_segments(rq->q)); | |
7027ad72 MP |
1098 | |
1099 | cmd->prot_sdb = prot_sdb; | |
1100 | cmd->prot_sdb->table.nents = count; | |
1101 | } | |
1102 | ||
159b2cbf | 1103 | return BLK_STS_OK; |
14784565 | 1104 | out_free_sgtables: |
20a66f2b | 1105 | scsi_free_sgtables(cmd); |
159b2cbf | 1106 | return ret; |
6f9a35e2 | 1107 | } |
7007e9dd | 1108 | EXPORT_SYMBOL(scsi_alloc_sgtables); |
1da177e4 | 1109 | |
ca18d6f7 | 1110 | /** |
832889f5 | 1111 | * scsi_initialize_rq - initialize struct scsi_cmnd partially |
35c0506f | 1112 | * @rq: Request associated with the SCSI command to be initialized. |
ca18d6f7 | 1113 | * |
832889f5 BVA |
1114 | * This function initializes the members of struct scsi_cmnd that must be |
1115 | * initialized before request processing starts and that won't be | |
1116 | * reinitialized if a SCSI command is requeued. | |
ca18d6f7 | 1117 | */ |
e4c9470b | 1118 | static void scsi_initialize_rq(struct request *rq) |
ca18d6f7 | 1119 | { |
c8d9cf22 BVA |
1120 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
1121 | ||
ce70fd9a CH |
1122 | memset(cmd->cmnd, 0, sizeof(cmd->cmnd)); |
1123 | cmd->cmd_len = MAX_COMMAND_SIZE; | |
5b794f98 | 1124 | cmd->sense_len = 0; |
3be8828f | 1125 | init_rcu_head(&cmd->rcu); |
832889f5 BVA |
1126 | cmd->jiffies_at_alloc = jiffies; |
1127 | cmd->retries = 0; | |
ca18d6f7 | 1128 | } |
ca18d6f7 | 1129 | |
ea957547 BVA |
1130 | struct request *scsi_alloc_request(struct request_queue *q, blk_opf_t opf, |
1131 | blk_mq_req_flags_t flags) | |
68ec3b81 CH |
1132 | { |
1133 | struct request *rq; | |
1134 | ||
ea957547 | 1135 | rq = blk_mq_alloc_request(q, opf, flags); |
68ec3b81 CH |
1136 | if (!IS_ERR(rq)) |
1137 | scsi_initialize_rq(rq); | |
1138 | return rq; | |
1139 | } | |
1140 | EXPORT_SYMBOL_GPL(scsi_alloc_request); | |
1141 | ||
b7e9e1fb ML |
1142 | /* |
1143 | * Only called when the request isn't completed by SCSI, and not freed by | |
1144 | * SCSI | |
1145 | */ | |
1146 | static void scsi_cleanup_rq(struct request *rq) | |
1147 | { | |
1148 | if (rq->rq_flags & RQF_DONTPREP) { | |
1149 | scsi_mq_uninit_cmd(blk_mq_rq_to_pdu(rq)); | |
1150 | rq->rq_flags &= ~RQF_DONTPREP; | |
1151 | } | |
1152 | } | |
1153 | ||
65ca846a | 1154 | /* Called before a request is prepared. See also scsi_mq_prep_fn(). */ |
e9c787e6 | 1155 | void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd) |
3b003157 | 1156 | { |
aa8e25e5 | 1157 | struct request *rq = scsi_cmd_to_rq(cmd); |
71bada34 CH |
1158 | |
1159 | if (!blk_rq_is_passthrough(rq) && !(cmd->flags & SCMD_INITIALIZED)) { | |
1160 | cmd->flags |= SCMD_INITIALIZED; | |
64104f70 BVA |
1161 | scsi_initialize_rq(rq); |
1162 | } | |
3b003157 | 1163 | |
e9c787e6 | 1164 | cmd->device = dev; |
5ae17501 | 1165 | INIT_LIST_HEAD(&cmd->eh_entry); |
e9c787e6 | 1166 | INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler); |
3b003157 CH |
1167 | } |
1168 | ||
785ba83b CH |
1169 | static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev, |
1170 | struct request *req) | |
7b16318d | 1171 | { |
bed2213d | 1172 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); |
3b003157 CH |
1173 | |
1174 | /* | |
aebf526b | 1175 | * Passthrough requests may transfer data, in which case they must |
3b003157 CH |
1176 | * a bio attached to them. Or they might contain a SCSI command |
1177 | * that does not transfer data, in which case they may optionally | |
1178 | * submit a request without an attached bio. | |
1179 | */ | |
1180 | if (req->bio) { | |
7007e9dd | 1181 | blk_status_t ret = scsi_alloc_sgtables(cmd); |
159b2cbf CH |
1182 | if (unlikely(ret != BLK_STS_OK)) |
1183 | return ret; | |
3b003157 | 1184 | } else { |
b0790410 | 1185 | BUG_ON(blk_rq_bytes(req)); |
3b003157 | 1186 | |
30b0c37b | 1187 | memset(&cmd->sdb, 0, sizeof(cmd->sdb)); |
3b003157 | 1188 | } |
7b16318d | 1189 | |
b0790410 | 1190 | cmd->transfersize = blk_rq_bytes(req); |
785ba83b | 1191 | return BLK_STS_OK; |
7b16318d | 1192 | } |
7b16318d | 1193 | |
c092d4ec | 1194 | static blk_status_t |
822bd2db | 1195 | scsi_device_state_check(struct scsi_device *sdev, struct request *req) |
3b003157 | 1196 | { |
c092d4ec | 1197 | switch (sdev->sdev_state) { |
e6044f71 BVA |
1198 | case SDEV_CREATED: |
1199 | return BLK_STS_OK; | |
c092d4ec CH |
1200 | case SDEV_OFFLINE: |
1201 | case SDEV_TRANSPORT_OFFLINE: | |
1202 | /* | |
1203 | * If the device is offline we refuse to process any | |
1204 | * commands. The device must be brought online | |
1205 | * before trying any recovery commands. | |
1206 | */ | |
b0962c53 EM |
1207 | if (!sdev->offline_already) { |
1208 | sdev->offline_already = true; | |
1209 | sdev_printk(KERN_ERR, sdev, | |
1210 | "rejecting I/O to offline device\n"); | |
1211 | } | |
c092d4ec CH |
1212 | return BLK_STS_IOERR; |
1213 | case SDEV_DEL: | |
1214 | /* | |
1215 | * If the device is fully deleted, we refuse to | |
1216 | * process any commands as well. | |
1217 | */ | |
1218 | sdev_printk(KERN_ERR, sdev, | |
1219 | "rejecting I/O to dead device\n"); | |
1220 | return BLK_STS_IOERR; | |
1221 | case SDEV_BLOCK: | |
1222 | case SDEV_CREATED_BLOCK: | |
1223 | return BLK_STS_RESOURCE; | |
1224 | case SDEV_QUIESCE: | |
1225 | /* | |
e6044f71 BVA |
1226 | * If the device is blocked we only accept power management |
1227 | * commands. | |
c092d4ec | 1228 | */ |
e6044f71 | 1229 | if (req && WARN_ON_ONCE(!(req->rq_flags & RQF_PM))) |
c092d4ec CH |
1230 | return BLK_STS_RESOURCE; |
1231 | return BLK_STS_OK; | |
1232 | default: | |
1233 | /* | |
1234 | * For any other not fully online state we only allow | |
e6044f71 | 1235 | * power management commands. |
c092d4ec | 1236 | */ |
e6044f71 | 1237 | if (req && !(req->rq_flags & RQF_PM)) |
9574d434 | 1238 | return BLK_STS_OFFLINE; |
c092d4ec | 1239 | return BLK_STS_OK; |
1da177e4 | 1240 | } |
7f9a6bc4 | 1241 | } |
1da177e4 | 1242 | |
1da177e4 | 1243 | /* |
020b0f0a ML |
1244 | * scsi_dev_queue_ready: if we can send requests to sdev, assign one token |
1245 | * and return the token else return -1. | |
1da177e4 LT |
1246 | */ |
1247 | static inline int scsi_dev_queue_ready(struct request_queue *q, | |
1248 | struct scsi_device *sdev) | |
1249 | { | |
020b0f0a | 1250 | int token; |
71e75c97 | 1251 | |
020b0f0a | 1252 | token = sbitmap_get(&sdev->budget_map); |
cd9070c9 | 1253 | if (atomic_read(&sdev->device_blocked)) { |
020b0f0a ML |
1254 | if (token < 0) |
1255 | goto out; | |
1256 | ||
1257 | if (scsi_device_busy(sdev) > 1) | |
71e75c97 CH |
1258 | goto out_dec; |
1259 | ||
1da177e4 LT |
1260 | /* |
1261 | * unblock after device_blocked iterates to zero | |
1262 | */ | |
f664a3cc | 1263 | if (atomic_dec_return(&sdev->device_blocked) > 0) |
71e75c97 | 1264 | goto out_dec; |
71e75c97 CH |
1265 | SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev, |
1266 | "unblocking device at zero depth\n")); | |
1da177e4 | 1267 | } |
71e75c97 | 1268 | |
020b0f0a | 1269 | return token; |
71e75c97 | 1270 | out_dec: |
020b0f0a ML |
1271 | if (token >= 0) |
1272 | sbitmap_put(&sdev->budget_map, token); | |
1273 | out: | |
1274 | return -1; | |
1da177e4 LT |
1275 | } |
1276 | ||
f0c0a376 MC |
1277 | /* |
1278 | * scsi_target_queue_ready: checks if there we can send commands to target | |
1279 | * @sdev: scsi device on starget to check. | |
f0c0a376 MC |
1280 | */ |
1281 | static inline int scsi_target_queue_ready(struct Scsi_Host *shost, | |
1282 | struct scsi_device *sdev) | |
1283 | { | |
1284 | struct scsi_target *starget = scsi_target(sdev); | |
7ae65c0f | 1285 | unsigned int busy; |
f0c0a376 MC |
1286 | |
1287 | if (starget->single_lun) { | |
7ae65c0f | 1288 | spin_lock_irq(shost->host_lock); |
f0c0a376 | 1289 | if (starget->starget_sdev_user && |
7ae65c0f CH |
1290 | starget->starget_sdev_user != sdev) { |
1291 | spin_unlock_irq(shost->host_lock); | |
1292 | return 0; | |
1293 | } | |
f0c0a376 | 1294 | starget->starget_sdev_user = sdev; |
7ae65c0f | 1295 | spin_unlock_irq(shost->host_lock); |
f0c0a376 MC |
1296 | } |
1297 | ||
2ccbb008 CH |
1298 | if (starget->can_queue <= 0) |
1299 | return 1; | |
1300 | ||
7ae65c0f | 1301 | busy = atomic_inc_return(&starget->target_busy) - 1; |
cd9070c9 | 1302 | if (atomic_read(&starget->target_blocked) > 0) { |
7ae65c0f CH |
1303 | if (busy) |
1304 | goto starved; | |
1305 | ||
f0c0a376 MC |
1306 | /* |
1307 | * unblock after target_blocked iterates to zero | |
1308 | */ | |
cd9070c9 | 1309 | if (atomic_dec_return(&starget->target_blocked) > 0) |
7ae65c0f | 1310 | goto out_dec; |
cf68d334 CH |
1311 | |
1312 | SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget, | |
1313 | "unblocking target at zero depth\n")); | |
f0c0a376 MC |
1314 | } |
1315 | ||
2ccbb008 | 1316 | if (busy >= starget->can_queue) |
7ae65c0f | 1317 | goto starved; |
f0c0a376 | 1318 | |
7ae65c0f CH |
1319 | return 1; |
1320 | ||
1321 | starved: | |
1322 | spin_lock_irq(shost->host_lock); | |
1323 | list_move_tail(&sdev->starved_entry, &shost->starved_list); | |
cf68d334 | 1324 | spin_unlock_irq(shost->host_lock); |
7ae65c0f | 1325 | out_dec: |
2ccbb008 CH |
1326 | if (starget->can_queue > 0) |
1327 | atomic_dec(&starget->target_busy); | |
7ae65c0f | 1328 | return 0; |
f0c0a376 MC |
1329 | } |
1330 | ||
1da177e4 LT |
1331 | /* |
1332 | * scsi_host_queue_ready: if we can send requests to shost, return 1 else | |
1333 | * return 0. We must end up running the queue again whenever 0 is | |
1334 | * returned, else IO can hang. | |
1da177e4 LT |
1335 | */ |
1336 | static inline int scsi_host_queue_ready(struct request_queue *q, | |
1337 | struct Scsi_Host *shost, | |
6eb045e0 ML |
1338 | struct scsi_device *sdev, |
1339 | struct scsi_cmnd *cmd) | |
1da177e4 | 1340 | { |
cd9070c9 | 1341 | if (atomic_read(&shost->host_blocked) > 0) { |
6eb045e0 | 1342 | if (scsi_host_busy(shost) > 0) |
74665016 CH |
1343 | goto starved; |
1344 | ||
1da177e4 LT |
1345 | /* |
1346 | * unblock after host_blocked iterates to zero | |
1347 | */ | |
cd9070c9 | 1348 | if (atomic_dec_return(&shost->host_blocked) > 0) |
74665016 | 1349 | goto out_dec; |
cf68d334 CH |
1350 | |
1351 | SCSI_LOG_MLQUEUE(3, | |
1352 | shost_printk(KERN_INFO, shost, | |
1353 | "unblocking host at zero depth\n")); | |
1da177e4 | 1354 | } |
74665016 | 1355 | |
74665016 CH |
1356 | if (shost->host_self_blocked) |
1357 | goto starved; | |
1da177e4 LT |
1358 | |
1359 | /* We're OK to process the command, so we can't be starved */ | |
74665016 CH |
1360 | if (!list_empty(&sdev->starved_entry)) { |
1361 | spin_lock_irq(shost->host_lock); | |
1362 | if (!list_empty(&sdev->starved_entry)) | |
1363 | list_del_init(&sdev->starved_entry); | |
1364 | spin_unlock_irq(shost->host_lock); | |
1365 | } | |
1da177e4 | 1366 | |
6eb045e0 ML |
1367 | __set_bit(SCMD_STATE_INFLIGHT, &cmd->state); |
1368 | ||
74665016 CH |
1369 | return 1; |
1370 | ||
1371 | starved: | |
1372 | spin_lock_irq(shost->host_lock); | |
1373 | if (list_empty(&sdev->starved_entry)) | |
1374 | list_add_tail(&sdev->starved_entry, &shost->starved_list); | |
cf68d334 | 1375 | spin_unlock_irq(shost->host_lock); |
74665016 | 1376 | out_dec: |
6eb045e0 | 1377 | scsi_dec_host_busy(shost, cmd); |
74665016 | 1378 | return 0; |
1da177e4 LT |
1379 | } |
1380 | ||
6c5121b7 KU |
1381 | /* |
1382 | * Busy state exporting function for request stacking drivers. | |
1383 | * | |
1384 | * For efficiency, no lock is taken to check the busy state of | |
1385 | * shost/starget/sdev, since the returned value is not guaranteed and | |
1386 | * may be changed after request stacking drivers call the function, | |
1387 | * regardless of taking lock or not. | |
1388 | * | |
67bd9413 BVA |
1389 | * When scsi can't dispatch I/Os anymore and needs to kill I/Os scsi |
1390 | * needs to return 'not busy'. Otherwise, request stacking drivers | |
1391 | * may hold requests forever. | |
6c5121b7 | 1392 | */ |
f664a3cc | 1393 | static bool scsi_mq_lld_busy(struct request_queue *q) |
6c5121b7 KU |
1394 | { |
1395 | struct scsi_device *sdev = q->queuedata; | |
1396 | struct Scsi_Host *shost; | |
6c5121b7 | 1397 | |
3f3299d5 | 1398 | if (blk_queue_dying(q)) |
f664a3cc | 1399 | return false; |
6c5121b7 KU |
1400 | |
1401 | shost = sdev->host; | |
6c5121b7 | 1402 | |
b7e94a16 JN |
1403 | /* |
1404 | * Ignore host/starget busy state. | |
1405 | * Since block layer does not have a concept of fairness across | |
1406 | * multiple queues, congestion of host/starget needs to be handled | |
1407 | * in SCSI layer. | |
1408 | */ | |
1409 | if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev)) | |
f664a3cc | 1410 | return true; |
e36e0c80 | 1411 | |
f664a3cc | 1412 | return false; |
1da177e4 LT |
1413 | } |
1414 | ||
0d2810cd BVA |
1415 | /* |
1416 | * Block layer request completion callback. May be called from interrupt | |
1417 | * context. | |
1418 | */ | |
1419 | static void scsi_complete(struct request *rq) | |
1aea6434 | 1420 | { |
bed2213d | 1421 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
b8e162f9 | 1422 | enum scsi_disposition disposition; |
1aea6434 JA |
1423 | |
1424 | INIT_LIST_HEAD(&cmd->eh_entry); | |
1425 | ||
242f9dcb JA |
1426 | atomic_inc(&cmd->device->iodone_cnt); |
1427 | if (cmd->result) | |
1428 | atomic_inc(&cmd->device->ioerr_cnt); | |
1429 | ||
1aea6434 | 1430 | disposition = scsi_decide_disposition(cmd); |
2a242d59 | 1431 | if (disposition != SUCCESS && scsi_cmd_runtime_exceeced(cmd)) |
1aea6434 | 1432 | disposition = SUCCESS; |
91921e01 | 1433 | |
1aea6434 JA |
1434 | scsi_log_completion(cmd, disposition); |
1435 | ||
1436 | switch (disposition) { | |
4c7b4d63 BH |
1437 | case SUCCESS: |
1438 | scsi_finish_command(cmd); | |
1439 | break; | |
1440 | case NEEDS_RETRY: | |
1441 | scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY); | |
1442 | break; | |
1443 | case ADD_TO_MLQUEUE: | |
1444 | scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); | |
1445 | break; | |
1446 | default: | |
1447 | scsi_eh_scmd_add(cmd); | |
1448 | break; | |
1aea6434 JA |
1449 | } |
1450 | } | |
1451 | ||
82042a2c | 1452 | /** |
ae6b4e69 | 1453 | * scsi_dispatch_cmd - Dispatch a command to the low-level driver. |
82042a2c CH |
1454 | * @cmd: command block we are dispatching. |
1455 | * | |
1456 | * Return: nonzero return request was rejected and device's queue needs to be | |
1457 | * plugged. | |
1458 | */ | |
1459 | static int scsi_dispatch_cmd(struct scsi_cmnd *cmd) | |
1460 | { | |
1461 | struct Scsi_Host *host = cmd->device->host; | |
1462 | int rtn = 0; | |
1463 | ||
6ca9818d WH |
1464 | atomic_inc(&cmd->device->iorequest_cnt); |
1465 | ||
82042a2c CH |
1466 | /* check if the device is still usable */ |
1467 | if (unlikely(cmd->device->sdev_state == SDEV_DEL)) { | |
1468 | /* in SDEV_DEL we error all commands. DID_NO_CONNECT | |
1469 | * returns an immediate error upwards, and signals | |
1470 | * that the device is no longer present */ | |
1471 | cmd->result = DID_NO_CONNECT << 16; | |
1472 | goto done; | |
1473 | } | |
1474 | ||
1475 | /* Check to see if the scsi lld made this device blocked. */ | |
1476 | if (unlikely(scsi_device_blocked(cmd->device))) { | |
1477 | /* | |
1478 | * in blocked state, the command is just put back on | |
1479 | * the device queue. The suspend state has already | |
1480 | * blocked the queue so future requests should not | |
1481 | * occur until the device transitions out of the | |
1482 | * suspend state. | |
1483 | */ | |
1484 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd, | |
1485 | "queuecommand : device blocked\n")); | |
09e797c8 | 1486 | atomic_dec(&cmd->device->iorequest_cnt); |
82042a2c CH |
1487 | return SCSI_MLQUEUE_DEVICE_BUSY; |
1488 | } | |
1489 | ||
1490 | /* Store the LUN value in cmnd, if needed. */ | |
1491 | if (cmd->device->lun_in_cdb) | |
1492 | cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) | | |
1493 | (cmd->device->lun << 5 & 0xe0); | |
1494 | ||
1495 | scsi_log_send(cmd); | |
1496 | ||
1497 | /* | |
1498 | * Before we queue this command, check if the command | |
1499 | * length exceeds what the host adapter can handle. | |
1500 | */ | |
1501 | if (cmd->cmd_len > cmd->device->host->max_cmd_len) { | |
1502 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd, | |
1503 | "queuecommand : command too long. " | |
1504 | "cdb_size=%d host->max_cmd_len=%d\n", | |
1505 | cmd->cmd_len, cmd->device->host->max_cmd_len)); | |
1506 | cmd->result = (DID_ABORT << 16); | |
1507 | goto done; | |
1508 | } | |
1509 | ||
1510 | if (unlikely(host->shost_state == SHOST_DEL)) { | |
1511 | cmd->result = (DID_NO_CONNECT << 16); | |
1512 | goto done; | |
1513 | ||
1514 | } | |
1515 | ||
1516 | trace_scsi_dispatch_cmd_start(cmd); | |
1517 | rtn = host->hostt->queuecommand(host, cmd); | |
1518 | if (rtn) { | |
09e797c8 | 1519 | atomic_dec(&cmd->device->iorequest_cnt); |
82042a2c CH |
1520 | trace_scsi_dispatch_cmd_error(cmd, rtn); |
1521 | if (rtn != SCSI_MLQUEUE_DEVICE_BUSY && | |
1522 | rtn != SCSI_MLQUEUE_TARGET_BUSY) | |
1523 | rtn = SCSI_MLQUEUE_HOST_BUSY; | |
1524 | ||
1525 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd, | |
1526 | "queuecommand : request rejected\n")); | |
1527 | } | |
1528 | ||
1529 | return rtn; | |
1530 | done: | |
11b68e36 | 1531 | scsi_done(cmd); |
82042a2c CH |
1532 | return 0; |
1533 | } | |
1534 | ||
be4c186c | 1535 | /* Size in bytes of the sg-list stored in the scsi-mq command-private data. */ |
3dccdf53 | 1536 | static unsigned int scsi_mq_inline_sgl_size(struct Scsi_Host *shost) |
be4c186c | 1537 | { |
3dccdf53 | 1538 | return min_t(unsigned int, shost->sg_tablesize, SCSI_INLINE_SG_CNT) * |
be4c186c BVA |
1539 | sizeof(struct scatterlist); |
1540 | } | |
1541 | ||
5843cc3d | 1542 | static blk_status_t scsi_prepare_cmd(struct request *req) |
d285203c CH |
1543 | { |
1544 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); | |
1545 | struct scsi_device *sdev = req->q->queuedata; | |
1546 | struct Scsi_Host *shost = sdev->host; | |
71bada34 | 1547 | bool in_flight = test_bit(SCMD_STATE_INFLIGHT, &cmd->state); |
d285203c CH |
1548 | struct scatterlist *sg; |
1549 | ||
08f78436 | 1550 | scsi_init_command(sdev, cmd); |
d285203c | 1551 | |
71bada34 | 1552 | cmd->eh_eflags = 0; |
71bada34 CH |
1553 | cmd->prot_type = 0; |
1554 | cmd->prot_flags = 0; | |
1555 | cmd->submitter = 0; | |
71bada34 CH |
1556 | memset(&cmd->sdb, 0, sizeof(cmd->sdb)); |
1557 | cmd->underflow = 0; | |
1558 | cmd->transfersize = 0; | |
1559 | cmd->host_scribble = NULL; | |
1560 | cmd->result = 0; | |
1561 | cmd->extra_len = 0; | |
1562 | cmd->state = 0; | |
1563 | if (in_flight) | |
1564 | __set_bit(SCMD_STATE_INFLIGHT, &cmd->state); | |
1565 | ||
1566 | /* | |
1567 | * Only clear the driver-private command data if the LLD does not supply | |
1568 | * a function to initialize that data. | |
1569 | */ | |
1570 | if (!shost->hostt->init_cmd_priv) | |
1571 | memset(cmd + 1, 0, shost->hostt->cmd_size); | |
1572 | ||
d285203c | 1573 | cmd->prot_op = SCSI_PROT_NORMAL; |
b6ba9b0e CH |
1574 | if (blk_rq_bytes(req)) |
1575 | cmd->sc_data_direction = rq_dma_dir(req); | |
1576 | else | |
1577 | cmd->sc_data_direction = DMA_NONE; | |
d285203c | 1578 | |
d285203c CH |
1579 | sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size; |
1580 | cmd->sdb.table.sgl = sg; | |
1581 | ||
1582 | if (scsi_host_get_prot(shost)) { | |
d285203c CH |
1583 | memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer)); |
1584 | ||
1585 | cmd->prot_sdb->table.sgl = | |
1586 | (struct scatterlist *)(cmd->prot_sdb + 1); | |
1587 | } | |
1588 | ||
74e5e6c1 CH |
1589 | /* |
1590 | * Special handling for passthrough commands, which don't go to the ULP | |
1591 | * at all: | |
1592 | */ | |
da6269da | 1593 | if (blk_rq_is_passthrough(req)) |
74e5e6c1 CH |
1594 | return scsi_setup_scsi_cmnd(sdev, req); |
1595 | ||
1596 | if (sdev->handler && sdev->handler->prep_fn) { | |
1597 | blk_status_t ret = sdev->handler->prep_fn(sdev, req); | |
fe052529 | 1598 | |
74e5e6c1 CH |
1599 | if (ret != BLK_STS_OK) |
1600 | return ret; | |
1601 | } | |
1602 | ||
fac8e558 MC |
1603 | /* Usually overridden by the ULP */ |
1604 | cmd->allowed = 0; | |
ce70fd9a | 1605 | memset(cmd->cmnd, 0, sizeof(cmd->cmnd)); |
74e5e6c1 | 1606 | return scsi_cmd_to_driver(cmd)->init_command(cmd); |
d285203c CH |
1607 | } |
1608 | ||
b84b6ec0 | 1609 | static void scsi_done_internal(struct scsi_cmnd *cmd, bool complete_directly) |
d285203c | 1610 | { |
b84b6ec0 SAS |
1611 | struct request *req = scsi_cmd_to_rq(cmd); |
1612 | ||
bf23e619 BVA |
1613 | switch (cmd->submitter) { |
1614 | case SUBMITTED_BY_BLOCK_LAYER: | |
1615 | break; | |
1616 | case SUBMITTED_BY_SCSI_ERROR_HANDLER: | |
1617 | return scsi_eh_done(cmd); | |
1618 | case SUBMITTED_BY_SCSI_RESET_IOCTL: | |
1619 | return; | |
1620 | } | |
1621 | ||
aa8e25e5 | 1622 | if (unlikely(blk_should_fake_timeout(scsi_cmd_to_rq(cmd)->q))) |
15f73f5b | 1623 | return; |
f1342709 KB |
1624 | if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state))) |
1625 | return; | |
d285203c | 1626 | trace_scsi_dispatch_cmd_done(cmd); |
b84b6ec0 SAS |
1627 | |
1628 | if (complete_directly) | |
1629 | blk_mq_complete_request_direct(req, scsi_complete); | |
1630 | else | |
1631 | blk_mq_complete_request(req); | |
1632 | } | |
1633 | ||
1634 | void scsi_done(struct scsi_cmnd *cmd) | |
1635 | { | |
1636 | scsi_done_internal(cmd, false); | |
d285203c | 1637 | } |
a710eacb | 1638 | EXPORT_SYMBOL(scsi_done); |
d285203c | 1639 | |
b84b6ec0 SAS |
1640 | void scsi_done_direct(struct scsi_cmnd *cmd) |
1641 | { | |
1642 | scsi_done_internal(cmd, true); | |
1643 | } | |
1644 | EXPORT_SYMBOL(scsi_done_direct); | |
1645 | ||
2a5a24aa | 1646 | static void scsi_mq_put_budget(struct request_queue *q, int budget_token) |
d285203c | 1647 | { |
0df21c86 | 1648 | struct scsi_device *sdev = q->queuedata; |
0df21c86 | 1649 | |
020b0f0a | 1650 | sbitmap_put(&sdev->budget_map, budget_token); |
0df21c86 ML |
1651 | } |
1652 | ||
90552cd2 BVA |
1653 | /* |
1654 | * When to reinvoke queueing after a resource shortage. It's 3 msecs to | |
1655 | * not change behaviour from the previous unplug mechanism, experimentation | |
1656 | * may prove this needs changing. | |
1657 | */ | |
1658 | #define SCSI_QUEUE_DELAY 3 | |
1659 | ||
2a5a24aa | 1660 | static int scsi_mq_get_budget(struct request_queue *q) |
0df21c86 | 1661 | { |
d285203c | 1662 | struct scsi_device *sdev = q->queuedata; |
020b0f0a | 1663 | int token = scsi_dev_queue_ready(q, sdev); |
d285203c | 1664 | |
020b0f0a ML |
1665 | if (token >= 0) |
1666 | return token; | |
ed5dd6a6 ML |
1667 | |
1668 | atomic_inc(&sdev->restarts); | |
1669 | ||
1670 | /* | |
1671 | * Orders atomic_inc(&sdev->restarts) and atomic_read(&sdev->device_busy). | |
1672 | * .restarts must be incremented before .device_busy is read because the | |
1673 | * code in scsi_run_queue_async() depends on the order of these operations. | |
1674 | */ | |
1675 | smp_mb__after_atomic(); | |
1676 | ||
1677 | /* | |
1678 | * If all in-flight requests originated from this LUN are completed | |
1679 | * before reading .device_busy, sdev->device_busy will be observed as | |
1680 | * zero, then blk_mq_delay_run_hw_queues() will dispatch this request | |
1681 | * soon. Otherwise, completion of one of these requests will observe | |
1682 | * the .restarts flag, and the request queue will be run for handling | |
1683 | * this request, see scsi_end_request(). | |
1684 | */ | |
8278807a | 1685 | if (unlikely(scsi_device_busy(sdev) == 0 && |
ed5dd6a6 ML |
1686 | !scsi_device_blocked(sdev))) |
1687 | blk_mq_delay_run_hw_queues(sdev->request_queue, SCSI_QUEUE_DELAY); | |
2a5a24aa | 1688 | return -1; |
0df21c86 ML |
1689 | } |
1690 | ||
d022d18c ML |
1691 | static void scsi_mq_set_rq_budget_token(struct request *req, int token) |
1692 | { | |
1693 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); | |
1694 | ||
1695 | cmd->budget_token = token; | |
1696 | } | |
1697 | ||
1698 | static int scsi_mq_get_rq_budget_token(struct request *req) | |
1699 | { | |
1700 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); | |
1701 | ||
1702 | return cmd->budget_token; | |
0df21c86 ML |
1703 | } |
1704 | ||
fc17b653 | 1705 | static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, |
74c45052 | 1706 | const struct blk_mq_queue_data *bd) |
d285203c | 1707 | { |
74c45052 | 1708 | struct request *req = bd->rq; |
d285203c CH |
1709 | struct request_queue *q = req->q; |
1710 | struct scsi_device *sdev = q->queuedata; | |
1711 | struct Scsi_Host *shost = sdev->host; | |
1712 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); | |
fc17b653 | 1713 | blk_status_t ret; |
d285203c CH |
1714 | int reason; |
1715 | ||
2a5a24aa ML |
1716 | WARN_ON_ONCE(cmd->budget_token < 0); |
1717 | ||
c092d4ec CH |
1718 | /* |
1719 | * If the device is not in running state we will reject some or all | |
1720 | * commands. | |
1721 | */ | |
1722 | if (unlikely(sdev->sdev_state != SDEV_RUNNING)) { | |
822bd2db | 1723 | ret = scsi_device_state_check(sdev, req); |
c092d4ec CH |
1724 | if (ret != BLK_STS_OK) |
1725 | goto out_put_budget; | |
1726 | } | |
d285203c | 1727 | |
fc17b653 | 1728 | ret = BLK_STS_RESOURCE; |
d285203c | 1729 | if (!scsi_target_queue_ready(shost, sdev)) |
826a70a0 | 1730 | goto out_put_budget; |
310bcaef BVA |
1731 | if (unlikely(scsi_host_in_recovery(shost))) { |
1732 | if (cmd->flags & SCMD_FAIL_IF_RECOVERING) | |
1733 | ret = BLK_STS_OFFLINE; | |
1734 | goto out_dec_target_busy; | |
1735 | } | |
6eb045e0 | 1736 | if (!scsi_host_queue_ready(q, shost, sdev, cmd)) |
d285203c CH |
1737 | goto out_dec_target_busy; |
1738 | ||
e8064021 | 1739 | if (!(req->rq_flags & RQF_DONTPREP)) { |
5843cc3d | 1740 | ret = scsi_prepare_cmd(req); |
fc17b653 | 1741 | if (ret != BLK_STS_OK) |
d285203c | 1742 | goto out_dec_host_busy; |
e8064021 | 1743 | req->rq_flags |= RQF_DONTPREP; |
fe052529 | 1744 | } else { |
cd464d83 | 1745 | clear_bit(SCMD_STATE_COMPLETE, &cmd->state); |
d285203c CH |
1746 | } |
1747 | ||
8930a6c2 | 1748 | cmd->flags &= SCMD_PRESERVED_FLAGS; |
125c99bc CH |
1749 | if (sdev->simple_tags) |
1750 | cmd->flags |= SCMD_TAGGED; | |
8930a6c2 PB |
1751 | if (bd->last) |
1752 | cmd->flags |= SCMD_LAST; | |
b1dd2aac | 1753 | |
3a8dc5bb CH |
1754 | scsi_set_resid(cmd, 0); |
1755 | memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); | |
bf23e619 | 1756 | cmd->submitter = SUBMITTED_BY_BLOCK_LAYER; |
d285203c | 1757 | |
ed7fb2d0 | 1758 | blk_mq_start_request(req); |
d285203c CH |
1759 | reason = scsi_dispatch_cmd(cmd); |
1760 | if (reason) { | |
1761 | scsi_set_blocked(cmd, reason); | |
fc17b653 | 1762 | ret = BLK_STS_RESOURCE; |
d285203c CH |
1763 | goto out_dec_host_busy; |
1764 | } | |
1765 | ||
fc17b653 | 1766 | return BLK_STS_OK; |
d285203c CH |
1767 | |
1768 | out_dec_host_busy: | |
6eb045e0 | 1769 | scsi_dec_host_busy(shost, cmd); |
d285203c CH |
1770 | out_dec_target_busy: |
1771 | if (scsi_target(sdev)->can_queue > 0) | |
1772 | atomic_dec(&scsi_target(sdev)->target_busy); | |
0df21c86 | 1773 | out_put_budget: |
2a5a24aa ML |
1774 | scsi_mq_put_budget(q, cmd->budget_token); |
1775 | cmd->budget_token = -1; | |
d285203c | 1776 | switch (ret) { |
fc17b653 CH |
1777 | case BLK_STS_OK: |
1778 | break; | |
1779 | case BLK_STS_RESOURCE: | |
0512a75b | 1780 | case BLK_STS_ZONE_RESOURCE: |
673235f9 | 1781 | if (scsi_device_blocked(sdev)) |
86ff7c2a | 1782 | ret = BLK_STS_DEV_RESOURCE; |
d285203c | 1783 | break; |
268940b8 | 1784 | case BLK_STS_AGAIN: |
dbb4c84d | 1785 | cmd->result = DID_BUS_BUSY << 16; |
268940b8 HR |
1786 | if (req->rq_flags & RQF_DONTPREP) |
1787 | scsi_mq_uninit_cmd(cmd); | |
1788 | break; | |
fc17b653 | 1789 | default: |
be549d49 | 1790 | if (unlikely(!scsi_device_online(sdev))) |
dbb4c84d | 1791 | cmd->result = DID_NO_CONNECT << 16; |
be549d49 | 1792 | else |
dbb4c84d | 1793 | cmd->result = DID_ERROR << 16; |
d285203c | 1794 | /* |
be549d49 | 1795 | * Make sure to release all allocated resources when |
d285203c CH |
1796 | * we hit an error, as we will never see this command |
1797 | * again. | |
1798 | */ | |
e8064021 | 1799 | if (req->rq_flags & RQF_DONTPREP) |
d285203c | 1800 | scsi_mq_uninit_cmd(cmd); |
3f0dcfbc | 1801 | scsi_run_queue_async(sdev); |
d285203c | 1802 | break; |
d285203c CH |
1803 | } |
1804 | return ret; | |
1805 | } | |
1806 | ||
e7008ff5 BVA |
1807 | static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq, |
1808 | unsigned int hctx_idx, unsigned int numa_node) | |
d285203c | 1809 | { |
d6296d39 | 1810 | struct Scsi_Host *shost = set->driver_data; |
d285203c | 1811 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
08f78436 | 1812 | struct scatterlist *sg; |
65ca846a | 1813 | int ret = 0; |
d285203c | 1814 | |
aaff5eba CH |
1815 | cmd->sense_buffer = |
1816 | kmem_cache_alloc_node(scsi_sense_cache, GFP_KERNEL, numa_node); | |
d285203c CH |
1817 | if (!cmd->sense_buffer) |
1818 | return -ENOMEM; | |
08f78436 BVA |
1819 | |
1820 | if (scsi_host_get_prot(shost)) { | |
1821 | sg = (void *)cmd + sizeof(struct scsi_cmnd) + | |
1822 | shost->hostt->cmd_size; | |
3dccdf53 | 1823 | cmd->prot_sdb = (void *)sg + scsi_mq_inline_sgl_size(shost); |
08f78436 BVA |
1824 | } |
1825 | ||
65ca846a BVA |
1826 | if (shost->hostt->init_cmd_priv) { |
1827 | ret = shost->hostt->init_cmd_priv(shost, cmd); | |
1828 | if (ret < 0) | |
aaff5eba | 1829 | kmem_cache_free(scsi_sense_cache, cmd->sense_buffer); |
65ca846a BVA |
1830 | } |
1831 | ||
1832 | return ret; | |
d285203c CH |
1833 | } |
1834 | ||
e7008ff5 BVA |
1835 | static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq, |
1836 | unsigned int hctx_idx) | |
d285203c | 1837 | { |
65ca846a | 1838 | struct Scsi_Host *shost = set->driver_data; |
d285203c CH |
1839 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); |
1840 | ||
65ca846a BVA |
1841 | if (shost->hostt->exit_cmd_priv) |
1842 | shost->hostt->exit_cmd_priv(shost, cmd); | |
aaff5eba | 1843 | kmem_cache_free(scsi_sense_cache, cmd->sense_buffer); |
d285203c CH |
1844 | } |
1845 | ||
af183095 | 1846 | |
5a72e899 | 1847 | static int scsi_mq_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) |
af183095 | 1848 | { |
4309ea74 | 1849 | struct Scsi_Host *shost = hctx->driver_data; |
af183095 KD |
1850 | |
1851 | if (shost->hostt->mq_poll) | |
1852 | return shost->hostt->mq_poll(shost, hctx->queue_num); | |
1853 | ||
1854 | return 0; | |
1855 | } | |
1856 | ||
4309ea74 KD |
1857 | static int scsi_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, |
1858 | unsigned int hctx_idx) | |
1859 | { | |
1860 | struct Scsi_Host *shost = data; | |
1861 | ||
1862 | hctx->driver_data = shost; | |
1863 | return 0; | |
1864 | } | |
1865 | ||
a4e1d0b7 | 1866 | static void scsi_map_queues(struct blk_mq_tag_set *set) |
2d9c5c20 CH |
1867 | { |
1868 | struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set); | |
1869 | ||
1870 | if (shost->hostt->map_queues) | |
1871 | return shost->hostt->map_queues(shost); | |
a4e1d0b7 | 1872 | blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]); |
2d9c5c20 CH |
1873 | } |
1874 | ||
d48777a6 | 1875 | void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) |
1da177e4 | 1876 | { |
6f381fa3 | 1877 | struct device *dev = shost->dma_dev; |
1da177e4 | 1878 | |
a8474ce2 JA |
1879 | /* |
1880 | * this limit is imposed by hardware restrictions | |
1881 | */ | |
8a78362c | 1882 | blk_queue_max_segments(q, min_t(unsigned short, shost->sg_tablesize, |
65e8617f | 1883 | SG_MAX_SEGMENTS)); |
a8474ce2 | 1884 | |
13f05c8d MP |
1885 | if (scsi_host_prot_dma(shost)) { |
1886 | shost->sg_prot_tablesize = | |
1887 | min_not_zero(shost->sg_prot_tablesize, | |
1888 | (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS); | |
1889 | BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize); | |
1890 | blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize); | |
1891 | } | |
1892 | ||
086fa5ff | 1893 | blk_queue_max_hw_sectors(q, shost->max_sectors); |
1da177e4 | 1894 | blk_queue_segment_boundary(q, shost->dma_boundary); |
99c84dbd | 1895 | dma_set_seg_boundary(dev, shost->dma_boundary); |
1da177e4 | 1896 | |
a8cf59a6 | 1897 | blk_queue_max_segment_size(q, shost->max_segment_size); |
7ad388d8 CH |
1898 | blk_queue_virt_boundary(q, shost->virt_boundary_mask); |
1899 | dma_set_max_seg_size(dev, queue_max_segment_size(q)); | |
465ff318 JB |
1900 | |
1901 | /* | |
90addc6b HC |
1902 | * Set a reasonable default alignment: The larger of 32-byte (dword), |
1903 | * which is a common minimum for HBAs, and the minimum DMA alignment, | |
1904 | * which is set by the platform. | |
1905 | * | |
1906 | * Devices that require a bigger alignment can increase it later. | |
465ff318 | 1907 | */ |
90addc6b | 1908 | blk_queue_dma_alignment(q, max(4, dma_get_cache_alignment()) - 1); |
d285203c | 1909 | } |
d48777a6 | 1910 | EXPORT_SYMBOL_GPL(__scsi_init_queue); |
465ff318 | 1911 | |
8930a6c2 PB |
1912 | static const struct blk_mq_ops scsi_mq_ops_no_commit = { |
1913 | .get_budget = scsi_mq_get_budget, | |
1914 | .put_budget = scsi_mq_put_budget, | |
1915 | .queue_rq = scsi_queue_rq, | |
0d2810cd | 1916 | .complete = scsi_complete, |
8930a6c2 PB |
1917 | .timeout = scsi_timeout, |
1918 | #ifdef CONFIG_BLK_DEBUG_FS | |
1919 | .show_rq = scsi_show_rq, | |
1920 | #endif | |
1921 | .init_request = scsi_mq_init_request, | |
1922 | .exit_request = scsi_mq_exit_request, | |
82a9ac71 | 1923 | .cleanup_rq = scsi_cleanup_rq, |
8930a6c2 PB |
1924 | .busy = scsi_mq_lld_busy, |
1925 | .map_queues = scsi_map_queues, | |
4309ea74 | 1926 | .init_hctx = scsi_init_hctx, |
af183095 | 1927 | .poll = scsi_mq_poll, |
d022d18c ML |
1928 | .set_rq_budget_token = scsi_mq_set_rq_budget_token, |
1929 | .get_rq_budget_token = scsi_mq_get_rq_budget_token, | |
8930a6c2 PB |
1930 | }; |
1931 | ||
1932 | ||
1933 | static void scsi_commit_rqs(struct blk_mq_hw_ctx *hctx) | |
1934 | { | |
4309ea74 | 1935 | struct Scsi_Host *shost = hctx->driver_data; |
8930a6c2 PB |
1936 | |
1937 | shost->hostt->commit_rqs(shost, hctx->queue_num); | |
1938 | } | |
1939 | ||
f363b089 | 1940 | static const struct blk_mq_ops scsi_mq_ops = { |
0df21c86 ML |
1941 | .get_budget = scsi_mq_get_budget, |
1942 | .put_budget = scsi_mq_put_budget, | |
d285203c | 1943 | .queue_rq = scsi_queue_rq, |
8930a6c2 | 1944 | .commit_rqs = scsi_commit_rqs, |
0d2810cd | 1945 | .complete = scsi_complete, |
0152fb6b | 1946 | .timeout = scsi_timeout, |
0eebd005 BVA |
1947 | #ifdef CONFIG_BLK_DEBUG_FS |
1948 | .show_rq = scsi_show_rq, | |
1949 | #endif | |
e7008ff5 BVA |
1950 | .init_request = scsi_mq_init_request, |
1951 | .exit_request = scsi_mq_exit_request, | |
b7e9e1fb | 1952 | .cleanup_rq = scsi_cleanup_rq, |
3a7ea2c4 | 1953 | .busy = scsi_mq_lld_busy, |
2d9c5c20 | 1954 | .map_queues = scsi_map_queues, |
4309ea74 | 1955 | .init_hctx = scsi_init_hctx, |
af183095 | 1956 | .poll = scsi_mq_poll, |
d022d18c ML |
1957 | .set_rq_budget_token = scsi_mq_set_rq_budget_token, |
1958 | .get_rq_budget_token = scsi_mq_get_rq_budget_token, | |
d285203c CH |
1959 | }; |
1960 | ||
d285203c CH |
1961 | int scsi_mq_setup_tags(struct Scsi_Host *shost) |
1962 | { | |
be4c186c | 1963 | unsigned int cmd_size, sgl_size; |
840e1b55 | 1964 | struct blk_mq_tag_set *tag_set = &shost->tag_set; |
d285203c | 1965 | |
9393c8de MS |
1966 | sgl_size = max_t(unsigned int, sizeof(struct scatterlist), |
1967 | scsi_mq_inline_sgl_size(shost)); | |
d285203c CH |
1968 | cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size; |
1969 | if (scsi_host_get_prot(shost)) | |
92524fa1 ML |
1970 | cmd_size += sizeof(struct scsi_data_buffer) + |
1971 | sizeof(struct scatterlist) * SCSI_INLINE_PROT_SG_CNT; | |
d285203c | 1972 | |
840e1b55 | 1973 | memset(tag_set, 0, sizeof(*tag_set)); |
8930a6c2 | 1974 | if (shost->hostt->commit_rqs) |
840e1b55 | 1975 | tag_set->ops = &scsi_mq_ops; |
8930a6c2 | 1976 | else |
840e1b55 YB |
1977 | tag_set->ops = &scsi_mq_ops_no_commit; |
1978 | tag_set->nr_hw_queues = shost->nr_hw_queues ? : 1; | |
af183095 | 1979 | tag_set->nr_maps = shost->nr_maps ? : 1; |
840e1b55 YB |
1980 | tag_set->queue_depth = shost->can_queue; |
1981 | tag_set->cmd_size = cmd_size; | |
973dac8a | 1982 | tag_set->numa_node = dev_to_node(shost->dma_dev); |
840e1b55 YB |
1983 | tag_set->flags = BLK_MQ_F_SHOULD_MERGE; |
1984 | tag_set->flags |= | |
24391c0d | 1985 | BLK_ALLOC_POLICY_TO_MQ_FLAG(shost->hostt->tag_alloc_policy); |
b125bb99 BVA |
1986 | if (shost->queuecommand_may_block) |
1987 | tag_set->flags |= BLK_MQ_F_BLOCKING; | |
840e1b55 | 1988 | tag_set->driver_data = shost; |
bdb01301 HR |
1989 | if (shost->host_tagset) |
1990 | tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED; | |
d285203c | 1991 | |
840e1b55 | 1992 | return blk_mq_alloc_tag_set(tag_set); |
d285203c CH |
1993 | } |
1994 | ||
8fe4ce58 | 1995 | void scsi_mq_free_tags(struct kref *kref) |
d285203c | 1996 | { |
8fe4ce58 BVA |
1997 | struct Scsi_Host *shost = container_of(kref, typeof(*shost), |
1998 | tagset_refcnt); | |
1999 | ||
d285203c | 2000 | blk_mq_free_tag_set(&shost->tag_set); |
8fe4ce58 | 2001 | complete(&shost->tagset_freed); |
d285203c CH |
2002 | } |
2003 | ||
857de6e0 HR |
2004 | /** |
2005 | * scsi_device_from_queue - return sdev associated with a request_queue | |
2006 | * @q: The request queue to return the sdev from | |
2007 | * | |
2008 | * Return the sdev associated with a request queue or NULL if the | |
2009 | * request_queue does not reference a SCSI device. | |
2010 | */ | |
2011 | struct scsi_device *scsi_device_from_queue(struct request_queue *q) | |
2012 | { | |
2013 | struct scsi_device *sdev = NULL; | |
2014 | ||
6b6fa7a5 SM |
2015 | if (q->mq_ops == &scsi_mq_ops_no_commit || |
2016 | q->mq_ops == &scsi_mq_ops) | |
857de6e0 HR |
2017 | sdev = q->queuedata; |
2018 | if (!sdev || !get_device(&sdev->sdev_gendev)) | |
2019 | sdev = NULL; | |
2020 | ||
2021 | return sdev; | |
2022 | } | |
4845012e CH |
2023 | /* |
2024 | * pktcdvd should have been integrated into the SCSI layers, but for historical | |
2025 | * reasons like the old IDE driver it isn't. This export allows it to safely | |
2026 | * probe if a given device is a SCSI one and only attach to that. | |
2027 | */ | |
2028 | #ifdef CONFIG_CDROM_PKTCDVD_MODULE | |
2029 | EXPORT_SYMBOL_GPL(scsi_device_from_queue); | |
2030 | #endif | |
857de6e0 | 2031 | |
ea941016 AA |
2032 | /** |
2033 | * scsi_block_requests - Utility function used by low-level drivers to prevent | |
2034 | * further commands from being queued to the device. | |
2035 | * @shost: host in question | |
1da177e4 | 2036 | * |
ea941016 AA |
2037 | * There is no timer nor any other means by which the requests get unblocked |
2038 | * other than the low-level driver calling scsi_unblock_requests(). | |
1da177e4 LT |
2039 | */ |
2040 | void scsi_block_requests(struct Scsi_Host *shost) | |
2041 | { | |
2042 | shost->host_self_blocked = 1; | |
2043 | } | |
2044 | EXPORT_SYMBOL(scsi_block_requests); | |
2045 | ||
ea941016 AA |
2046 | /** |
2047 | * scsi_unblock_requests - Utility function used by low-level drivers to allow | |
2048 | * further commands to be queued to the device. | |
2049 | * @shost: host in question | |
1da177e4 | 2050 | * |
ea941016 AA |
2051 | * There is no timer nor any other means by which the requests get unblocked |
2052 | * other than the low-level driver calling scsi_unblock_requests(). This is done | |
2053 | * as an API function so that changes to the internals of the scsi mid-layer | |
2054 | * won't require wholesale changes to drivers that use this feature. | |
1da177e4 LT |
2055 | */ |
2056 | void scsi_unblock_requests(struct Scsi_Host *shost) | |
2057 | { | |
2058 | shost->host_self_blocked = 0; | |
2059 | scsi_run_host_queues(shost); | |
2060 | } | |
2061 | EXPORT_SYMBOL(scsi_unblock_requests); | |
2062 | ||
1da177e4 LT |
2063 | void scsi_exit_queue(void) |
2064 | { | |
0a6ac4ee | 2065 | kmem_cache_destroy(scsi_sense_cache); |
1da177e4 | 2066 | } |
5baba830 JB |
2067 | |
2068 | /** | |
2069 | * scsi_mode_select - issue a mode select | |
2070 | * @sdev: SCSI device to be queried | |
2071 | * @pf: Page format bit (1 == standard, 0 == vendor specific) | |
2072 | * @sp: Save page bit (0 == don't save, 1 == save) | |
5baba830 JB |
2073 | * @buffer: request buffer (may not be smaller than eight bytes) |
2074 | * @len: length of request buffer. | |
2075 | * @timeout: command timeout | |
2076 | * @retries: number of retries before failing | |
2077 | * @data: returns a structure abstracting the mode header data | |
eb44820c | 2078 | * @sshdr: place to put sense data (or NULL if no sense to be collected). |
5baba830 JB |
2079 | * must be SCSI_SENSE_BUFFERSIZE big. |
2080 | * | |
2081 | * Returns zero if successful; negative error number or scsi | |
2082 | * status on error | |
2083 | * | |
2084 | */ | |
81d3f500 DLM |
2085 | int scsi_mode_select(struct scsi_device *sdev, int pf, int sp, |
2086 | unsigned char *buffer, int len, int timeout, int retries, | |
2087 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) | |
5baba830 JB |
2088 | { |
2089 | unsigned char cmd[10]; | |
2090 | unsigned char *real_buffer; | |
7dfe0b5e MC |
2091 | const struct scsi_exec_args exec_args = { |
2092 | .sshdr = sshdr, | |
2093 | }; | |
5baba830 JB |
2094 | int ret; |
2095 | ||
2096 | memset(cmd, 0, sizeof(cmd)); | |
2097 | cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0); | |
2098 | ||
a7d6840b DLM |
2099 | /* |
2100 | * Use MODE SELECT(10) if the device asked for it or if the mode page | |
2101 | * and the mode select header cannot fit within the maximumm 255 bytes | |
2102 | * of the MODE SELECT(6) command. | |
2103 | */ | |
2104 | if (sdev->use_10_for_ms || | |
2105 | len + 4 > 255 || | |
2106 | data->block_descriptor_length > 255) { | |
2107 | if (len > 65535 - 8) | |
5baba830 JB |
2108 | return -EINVAL; |
2109 | real_buffer = kmalloc(8 + len, GFP_KERNEL); | |
2110 | if (!real_buffer) | |
2111 | return -ENOMEM; | |
2112 | memcpy(real_buffer + 8, buffer, len); | |
2113 | len += 8; | |
2114 | real_buffer[0] = 0; | |
2115 | real_buffer[1] = 0; | |
2116 | real_buffer[2] = data->medium_type; | |
2117 | real_buffer[3] = data->device_specific; | |
2118 | real_buffer[4] = data->longlba ? 0x01 : 0; | |
2119 | real_buffer[5] = 0; | |
a7d6840b DLM |
2120 | put_unaligned_be16(data->block_descriptor_length, |
2121 | &real_buffer[6]); | |
5baba830 JB |
2122 | |
2123 | cmd[0] = MODE_SELECT_10; | |
a7d6840b | 2124 | put_unaligned_be16(len, &cmd[7]); |
5baba830 | 2125 | } else { |
a7d6840b | 2126 | if (data->longlba) |
5baba830 JB |
2127 | return -EINVAL; |
2128 | ||
2129 | real_buffer = kmalloc(4 + len, GFP_KERNEL); | |
2130 | if (!real_buffer) | |
2131 | return -ENOMEM; | |
2132 | memcpy(real_buffer + 4, buffer, len); | |
2133 | len += 4; | |
2134 | real_buffer[0] = 0; | |
2135 | real_buffer[1] = data->medium_type; | |
2136 | real_buffer[2] = data->device_specific; | |
2137 | real_buffer[3] = data->block_descriptor_length; | |
5baba830 JB |
2138 | |
2139 | cmd[0] = MODE_SELECT; | |
2140 | cmd[4] = len; | |
2141 | } | |
2142 | ||
7dfe0b5e MC |
2143 | ret = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_OUT, real_buffer, len, |
2144 | timeout, retries, &exec_args); | |
5baba830 JB |
2145 | kfree(real_buffer); |
2146 | return ret; | |
2147 | } | |
2148 | EXPORT_SYMBOL_GPL(scsi_mode_select); | |
2149 | ||
1da177e4 | 2150 | /** |
eb44820c | 2151 | * scsi_mode_sense - issue a mode sense, falling back from 10 to six bytes if necessary. |
1cf72699 | 2152 | * @sdev: SCSI device to be queried |
17b49bcb | 2153 | * @dbd: set to prevent mode sense from returning block descriptors |
1da177e4 | 2154 | * @modepage: mode page being requested |
a6cdc35f | 2155 | * @subpage: sub-page of the mode page being requested |
1da177e4 LT |
2156 | * @buffer: request buffer (may not be smaller than eight bytes) |
2157 | * @len: length of request buffer. | |
2158 | * @timeout: command timeout | |
2159 | * @retries: number of retries before failing | |
2160 | * @data: returns a structure abstracting the mode header data | |
eb44820c | 2161 | * @sshdr: place to put sense data (or NULL if no sense to be collected). |
1cf72699 | 2162 | * must be SCSI_SENSE_BUFFERSIZE big. |
1da177e4 | 2163 | * |
8793613d | 2164 | * Returns zero if successful, or a negative error number on failure |
eb44820c | 2165 | */ |
1da177e4 | 2166 | int |
a6cdc35f | 2167 | scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, int subpage, |
1da177e4 | 2168 | unsigned char *buffer, int len, int timeout, int retries, |
5baba830 JB |
2169 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) |
2170 | { | |
1da177e4 LT |
2171 | unsigned char cmd[12]; |
2172 | int use_10_for_ms; | |
2173 | int header_length; | |
0ae80ba9 | 2174 | int result, retry_count = retries; |
ea73a9f2 | 2175 | struct scsi_sense_hdr my_sshdr; |
7dfe0b5e MC |
2176 | const struct scsi_exec_args exec_args = { |
2177 | /* caller might not be interested in sense, but we need it */ | |
2178 | .sshdr = sshdr ? : &my_sshdr, | |
2179 | }; | |
1da177e4 LT |
2180 | |
2181 | memset(data, 0, sizeof(*data)); | |
2182 | memset(&cmd[0], 0, 12); | |
0ec96913 CG |
2183 | |
2184 | dbd = sdev->set_dbd_for_ms ? 8 : dbd; | |
1da177e4 LT |
2185 | cmd[1] = dbd & 0x18; /* allows DBD and LLBA bits */ |
2186 | cmd[2] = modepage; | |
a6cdc35f | 2187 | cmd[3] = subpage; |
1da177e4 | 2188 | |
7dfe0b5e | 2189 | sshdr = exec_args.sshdr; |
ea73a9f2 | 2190 | |
1da177e4 | 2191 | retry: |
17b49bcb | 2192 | use_10_for_ms = sdev->use_10_for_ms || len > 255; |
1da177e4 LT |
2193 | |
2194 | if (use_10_for_ms) { | |
17b49bcb DLM |
2195 | if (len < 8 || len > 65535) |
2196 | return -EINVAL; | |
1da177e4 LT |
2197 | |
2198 | cmd[0] = MODE_SENSE_10; | |
17b49bcb | 2199 | put_unaligned_be16(len, &cmd[7]); |
1da177e4 LT |
2200 | header_length = 8; |
2201 | } else { | |
2202 | if (len < 4) | |
17b49bcb | 2203 | return -EINVAL; |
1da177e4 LT |
2204 | |
2205 | cmd[0] = MODE_SENSE; | |
2206 | cmd[4] = len; | |
2207 | header_length = 4; | |
2208 | } | |
2209 | ||
1da177e4 LT |
2210 | memset(buffer, 0, len); |
2211 | ||
7dfe0b5e MC |
2212 | result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, buffer, len, |
2213 | timeout, retries, &exec_args); | |
8793613d HR |
2214 | if (result < 0) |
2215 | return result; | |
1da177e4 LT |
2216 | |
2217 | /* This code looks awful: what it's doing is making sure an | |
2218 | * ILLEGAL REQUEST sense return identifies the actual command | |
2219 | * byte as the problem. MODE_SENSE commands can return | |
2220 | * ILLEGAL REQUEST if the code page isn't supported */ | |
2221 | ||
64aaa3dd | 2222 | if (!scsi_status_is_good(result)) { |
464a00c9 | 2223 | if (scsi_sense_valid(sshdr)) { |
ea73a9f2 JB |
2224 | if ((sshdr->sense_key == ILLEGAL_REQUEST) && |
2225 | (sshdr->asc == 0x20) && (sshdr->ascq == 0)) { | |
4c7b4d63 | 2226 | /* |
17b49bcb DLM |
2227 | * Invalid command operation code: retry using |
2228 | * MODE SENSE(6) if this was a MODE SENSE(10) | |
2229 | * request, except if the request mode page is | |
2230 | * too large for MODE SENSE single byte | |
2231 | * allocation length field. | |
1da177e4 | 2232 | */ |
64aaa3dd | 2233 | if (use_10_for_ms) { |
17b49bcb DLM |
2234 | if (len > 255) |
2235 | return -EIO; | |
64aaa3dd HR |
2236 | sdev->use_10_for_ms = 0; |
2237 | goto retry; | |
2238 | } | |
2239 | } | |
d0672a03 | 2240 | if (scsi_status_is_check_condition(result) && |
64aaa3dd HR |
2241 | sshdr->sense_key == UNIT_ATTENTION && |
2242 | retry_count) { | |
2243 | retry_count--; | |
1da177e4 LT |
2244 | goto retry; |
2245 | } | |
2246 | } | |
64aaa3dd | 2247 | return -EIO; |
1da177e4 | 2248 | } |
64aaa3dd HR |
2249 | if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b && |
2250 | (modepage == 6 || modepage == 8))) { | |
2251 | /* Initio breakage? */ | |
2252 | header_length = 0; | |
2253 | data->length = 13; | |
2254 | data->medium_type = 0; | |
2255 | data->device_specific = 0; | |
2256 | data->longlba = 0; | |
2257 | data->block_descriptor_length = 0; | |
2258 | } else if (use_10_for_ms) { | |
17b49bcb | 2259 | data->length = get_unaligned_be16(&buffer[0]) + 2; |
64aaa3dd HR |
2260 | data->medium_type = buffer[2]; |
2261 | data->device_specific = buffer[3]; | |
2262 | data->longlba = buffer[4] & 0x01; | |
17b49bcb | 2263 | data->block_descriptor_length = get_unaligned_be16(&buffer[6]); |
64aaa3dd HR |
2264 | } else { |
2265 | data->length = buffer[0] + 1; | |
2266 | data->medium_type = buffer[1]; | |
2267 | data->device_specific = buffer[2]; | |
2268 | data->block_descriptor_length = buffer[3]; | |
1da177e4 | 2269 | } |
64aaa3dd HR |
2270 | data->header_length = header_length; |
2271 | ||
2272 | return 0; | |
1da177e4 LT |
2273 | } |
2274 | EXPORT_SYMBOL(scsi_mode_sense); | |
2275 | ||
001aac25 JB |
2276 | /** |
2277 | * scsi_test_unit_ready - test if unit is ready | |
2278 | * @sdev: scsi device to change the state of. | |
2279 | * @timeout: command timeout | |
2280 | * @retries: number of retries before failing | |
74a78ebd | 2281 | * @sshdr: outpout pointer for decoded sense information. |
001aac25 JB |
2282 | * |
2283 | * Returns zero if unsuccessful or an error if TUR failed. For | |
9f8a2c23 | 2284 | * removable media, UNIT_ATTENTION sets ->changed flag. |
001aac25 | 2285 | **/ |
1da177e4 | 2286 | int |
001aac25 | 2287 | scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries, |
74a78ebd | 2288 | struct scsi_sense_hdr *sshdr) |
1da177e4 | 2289 | { |
1da177e4 LT |
2290 | char cmd[] = { |
2291 | TEST_UNIT_READY, 0, 0, 0, 0, 0, | |
2292 | }; | |
7dfe0b5e MC |
2293 | const struct scsi_exec_args exec_args = { |
2294 | .sshdr = sshdr, | |
2295 | }; | |
1da177e4 | 2296 | int result; |
001aac25 | 2297 | |
001aac25 JB |
2298 | /* try to eat the UNIT_ATTENTION if there are enough retries */ |
2299 | do { | |
7dfe0b5e MC |
2300 | result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, NULL, 0, |
2301 | timeout, 1, &exec_args); | |
32c356d7 JB |
2302 | if (sdev->removable && scsi_sense_valid(sshdr) && |
2303 | sshdr->sense_key == UNIT_ATTENTION) | |
2304 | sdev->changed = 1; | |
2305 | } while (scsi_sense_valid(sshdr) && | |
2306 | sshdr->sense_key == UNIT_ATTENTION && --retries); | |
001aac25 | 2307 | |
1da177e4 LT |
2308 | return result; |
2309 | } | |
2310 | EXPORT_SYMBOL(scsi_test_unit_ready); | |
2311 | ||
2312 | /** | |
eb44820c | 2313 | * scsi_device_set_state - Take the given device through the device state model. |
1da177e4 LT |
2314 | * @sdev: scsi device to change the state of. |
2315 | * @state: state to change to. | |
2316 | * | |
23cb27fd | 2317 | * Returns zero if successful or an error if the requested |
1da177e4 | 2318 | * transition is illegal. |
eb44820c | 2319 | */ |
1da177e4 LT |
2320 | int |
2321 | scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) | |
2322 | { | |
2323 | enum scsi_device_state oldstate = sdev->sdev_state; | |
2324 | ||
2325 | if (state == oldstate) | |
2326 | return 0; | |
2327 | ||
2328 | switch (state) { | |
2329 | case SDEV_CREATED: | |
6f4267e3 JB |
2330 | switch (oldstate) { |
2331 | case SDEV_CREATED_BLOCK: | |
2332 | break; | |
2333 | default: | |
2334 | goto illegal; | |
2335 | } | |
2336 | break; | |
4c7b4d63 | 2337 | |
1da177e4 LT |
2338 | case SDEV_RUNNING: |
2339 | switch (oldstate) { | |
2340 | case SDEV_CREATED: | |
2341 | case SDEV_OFFLINE: | |
1b8d2620 | 2342 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2343 | case SDEV_QUIESCE: |
2344 | case SDEV_BLOCK: | |
2345 | break; | |
2346 | default: | |
2347 | goto illegal; | |
2348 | } | |
2349 | break; | |
2350 | ||
2351 | case SDEV_QUIESCE: | |
2352 | switch (oldstate) { | |
2353 | case SDEV_RUNNING: | |
2354 | case SDEV_OFFLINE: | |
1b8d2620 | 2355 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2356 | break; |
2357 | default: | |
2358 | goto illegal; | |
2359 | } | |
2360 | break; | |
2361 | ||
2362 | case SDEV_OFFLINE: | |
1b8d2620 | 2363 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2364 | switch (oldstate) { |
2365 | case SDEV_CREATED: | |
2366 | case SDEV_RUNNING: | |
2367 | case SDEV_QUIESCE: | |
2368 | case SDEV_BLOCK: | |
2369 | break; | |
2370 | default: | |
2371 | goto illegal; | |
2372 | } | |
2373 | break; | |
2374 | ||
2375 | case SDEV_BLOCK: | |
2376 | switch (oldstate) { | |
1da177e4 | 2377 | case SDEV_RUNNING: |
6f4267e3 | 2378 | case SDEV_CREATED_BLOCK: |
6cbb7aed | 2379 | case SDEV_QUIESCE: |
a33e5bfb | 2380 | case SDEV_OFFLINE: |
6f4267e3 JB |
2381 | break; |
2382 | default: | |
2383 | goto illegal; | |
2384 | } | |
2385 | break; | |
2386 | ||
2387 | case SDEV_CREATED_BLOCK: | |
2388 | switch (oldstate) { | |
2389 | case SDEV_CREATED: | |
1da177e4 LT |
2390 | break; |
2391 | default: | |
2392 | goto illegal; | |
2393 | } | |
2394 | break; | |
2395 | ||
2396 | case SDEV_CANCEL: | |
2397 | switch (oldstate) { | |
2398 | case SDEV_CREATED: | |
2399 | case SDEV_RUNNING: | |
9ea72909 | 2400 | case SDEV_QUIESCE: |
1da177e4 | 2401 | case SDEV_OFFLINE: |
1b8d2620 | 2402 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 LT |
2403 | break; |
2404 | default: | |
2405 | goto illegal; | |
2406 | } | |
2407 | break; | |
2408 | ||
2409 | case SDEV_DEL: | |
2410 | switch (oldstate) { | |
309bd271 BK |
2411 | case SDEV_CREATED: |
2412 | case SDEV_RUNNING: | |
2413 | case SDEV_OFFLINE: | |
1b8d2620 | 2414 | case SDEV_TRANSPORT_OFFLINE: |
1da177e4 | 2415 | case SDEV_CANCEL: |
255ee932 | 2416 | case SDEV_BLOCK: |
0516c08d | 2417 | case SDEV_CREATED_BLOCK: |
1da177e4 LT |
2418 | break; |
2419 | default: | |
2420 | goto illegal; | |
2421 | } | |
2422 | break; | |
2423 | ||
2424 | } | |
b0962c53 | 2425 | sdev->offline_already = false; |
1da177e4 LT |
2426 | sdev->sdev_state = state; |
2427 | return 0; | |
2428 | ||
2429 | illegal: | |
91921e01 | 2430 | SCSI_LOG_ERROR_RECOVERY(1, |
9ccfc756 | 2431 | sdev_printk(KERN_ERR, sdev, |
91921e01 | 2432 | "Illegal state transition %s->%s", |
9ccfc756 JB |
2433 | scsi_device_state_name(oldstate), |
2434 | scsi_device_state_name(state)) | |
1da177e4 LT |
2435 | ); |
2436 | return -EINVAL; | |
2437 | } | |
2438 | EXPORT_SYMBOL(scsi_device_set_state); | |
2439 | ||
a341cd0f | 2440 | /** |
ae6b4e69 | 2441 | * scsi_evt_emit - emit a single SCSI device uevent |
a341cd0f JG |
2442 | * @sdev: associated SCSI device |
2443 | * @evt: event to emit | |
2444 | * | |
2445 | * Send a single uevent (scsi_event) to the associated scsi_device. | |
2446 | */ | |
2447 | static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt) | |
2448 | { | |
2449 | int idx = 0; | |
2450 | char *envp[3]; | |
2451 | ||
2452 | switch (evt->evt_type) { | |
2453 | case SDEV_EVT_MEDIA_CHANGE: | |
2454 | envp[idx++] = "SDEV_MEDIA_CHANGE=1"; | |
2455 | break; | |
279afdfe | 2456 | case SDEV_EVT_INQUIRY_CHANGE_REPORTED: |
d3d32891 | 2457 | scsi_rescan_device(&sdev->sdev_gendev); |
279afdfe EM |
2458 | envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED"; |
2459 | break; | |
2460 | case SDEV_EVT_CAPACITY_CHANGE_REPORTED: | |
2461 | envp[idx++] = "SDEV_UA=CAPACITY_DATA_HAS_CHANGED"; | |
2462 | break; | |
2463 | case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED: | |
2464 | envp[idx++] = "SDEV_UA=THIN_PROVISIONING_SOFT_THRESHOLD_REACHED"; | |
2465 | break; | |
2466 | case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED: | |
2467 | envp[idx++] = "SDEV_UA=MODE_PARAMETERS_CHANGED"; | |
2468 | break; | |
2469 | case SDEV_EVT_LUN_CHANGE_REPORTED: | |
2470 | envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED"; | |
2471 | break; | |
14c3e677 HR |
2472 | case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED: |
2473 | envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED"; | |
2474 | break; | |
cf3431bb HR |
2475 | case SDEV_EVT_POWER_ON_RESET_OCCURRED: |
2476 | envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED"; | |
2477 | break; | |
a341cd0f JG |
2478 | default: |
2479 | /* do nothing */ | |
2480 | break; | |
2481 | } | |
2482 | ||
2483 | envp[idx++] = NULL; | |
2484 | ||
2485 | kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp); | |
2486 | } | |
2487 | ||
2488 | /** | |
ae6b4e69 | 2489 | * scsi_evt_thread - send a uevent for each scsi event |
a341cd0f JG |
2490 | * @work: work struct for scsi_device |
2491 | * | |
2492 | * Dispatch queued events to their associated scsi_device kobjects | |
2493 | * as uevents. | |
2494 | */ | |
2495 | void scsi_evt_thread(struct work_struct *work) | |
2496 | { | |
2497 | struct scsi_device *sdev; | |
279afdfe | 2498 | enum scsi_device_event evt_type; |
a341cd0f JG |
2499 | LIST_HEAD(event_list); |
2500 | ||
2501 | sdev = container_of(work, struct scsi_device, event_work); | |
2502 | ||
279afdfe EM |
2503 | for (evt_type = SDEV_EVT_FIRST; evt_type <= SDEV_EVT_LAST; evt_type++) |
2504 | if (test_and_clear_bit(evt_type, sdev->pending_events)) | |
2505 | sdev_evt_send_simple(sdev, evt_type, GFP_KERNEL); | |
2506 | ||
a341cd0f JG |
2507 | while (1) { |
2508 | struct scsi_event *evt; | |
2509 | struct list_head *this, *tmp; | |
2510 | unsigned long flags; | |
2511 | ||
2512 | spin_lock_irqsave(&sdev->list_lock, flags); | |
2513 | list_splice_init(&sdev->event_list, &event_list); | |
2514 | spin_unlock_irqrestore(&sdev->list_lock, flags); | |
2515 | ||
2516 | if (list_empty(&event_list)) | |
2517 | break; | |
2518 | ||
2519 | list_for_each_safe(this, tmp, &event_list) { | |
2520 | evt = list_entry(this, struct scsi_event, node); | |
2521 | list_del(&evt->node); | |
2522 | scsi_evt_emit(sdev, evt); | |
2523 | kfree(evt); | |
2524 | } | |
2525 | } | |
2526 | } | |
2527 | ||
2528 | /** | |
2529 | * sdev_evt_send - send asserted event to uevent thread | |
2530 | * @sdev: scsi_device event occurred on | |
2531 | * @evt: event to send | |
2532 | * | |
2533 | * Assert scsi device event asynchronously. | |
2534 | */ | |
2535 | void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt) | |
2536 | { | |
2537 | unsigned long flags; | |
2538 | ||
4d1566ed KS |
2539 | #if 0 |
2540 | /* FIXME: currently this check eliminates all media change events | |
2541 | * for polled devices. Need to update to discriminate between AN | |
2542 | * and polled events */ | |
a341cd0f JG |
2543 | if (!test_bit(evt->evt_type, sdev->supported_events)) { |
2544 | kfree(evt); | |
2545 | return; | |
2546 | } | |
4d1566ed | 2547 | #endif |
a341cd0f JG |
2548 | |
2549 | spin_lock_irqsave(&sdev->list_lock, flags); | |
2550 | list_add_tail(&evt->node, &sdev->event_list); | |
2551 | schedule_work(&sdev->event_work); | |
2552 | spin_unlock_irqrestore(&sdev->list_lock, flags); | |
2553 | } | |
2554 | EXPORT_SYMBOL_GPL(sdev_evt_send); | |
2555 | ||
2556 | /** | |
2557 | * sdev_evt_alloc - allocate a new scsi event | |
2558 | * @evt_type: type of event to allocate | |
2559 | * @gfpflags: GFP flags for allocation | |
2560 | * | |
2561 | * Allocates and returns a new scsi_event. | |
2562 | */ | |
2563 | struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type, | |
2564 | gfp_t gfpflags) | |
2565 | { | |
2566 | struct scsi_event *evt = kzalloc(sizeof(struct scsi_event), gfpflags); | |
2567 | if (!evt) | |
2568 | return NULL; | |
2569 | ||
2570 | evt->evt_type = evt_type; | |
2571 | INIT_LIST_HEAD(&evt->node); | |
2572 | ||
2573 | /* evt_type-specific initialization, if any */ | |
2574 | switch (evt_type) { | |
2575 | case SDEV_EVT_MEDIA_CHANGE: | |
279afdfe EM |
2576 | case SDEV_EVT_INQUIRY_CHANGE_REPORTED: |
2577 | case SDEV_EVT_CAPACITY_CHANGE_REPORTED: | |
2578 | case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED: | |
2579 | case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED: | |
2580 | case SDEV_EVT_LUN_CHANGE_REPORTED: | |
14c3e677 | 2581 | case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED: |
cf3431bb | 2582 | case SDEV_EVT_POWER_ON_RESET_OCCURRED: |
a341cd0f JG |
2583 | default: |
2584 | /* do nothing */ | |
2585 | break; | |
2586 | } | |
2587 | ||
2588 | return evt; | |
2589 | } | |
2590 | EXPORT_SYMBOL_GPL(sdev_evt_alloc); | |
2591 | ||
2592 | /** | |
2593 | * sdev_evt_send_simple - send asserted event to uevent thread | |
2594 | * @sdev: scsi_device event occurred on | |
2595 | * @evt_type: type of event to send | |
2596 | * @gfpflags: GFP flags for allocation | |
2597 | * | |
2598 | * Assert scsi device event asynchronously, given an event type. | |
2599 | */ | |
2600 | void sdev_evt_send_simple(struct scsi_device *sdev, | |
2601 | enum scsi_device_event evt_type, gfp_t gfpflags) | |
2602 | { | |
2603 | struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags); | |
2604 | if (!evt) { | |
2605 | sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n", | |
2606 | evt_type); | |
2607 | return; | |
2608 | } | |
2609 | ||
2610 | sdev_evt_send(sdev, evt); | |
2611 | } | |
2612 | EXPORT_SYMBOL_GPL(sdev_evt_send_simple); | |
2613 | ||
1da177e4 | 2614 | /** |
e6044f71 | 2615 | * scsi_device_quiesce - Block all commands except power management. |
1da177e4 LT |
2616 | * @sdev: scsi device to quiesce. |
2617 | * | |
2618 | * This works by trying to transition to the SDEV_QUIESCE state | |
2619 | * (which must be a legal transition). When the device is in this | |
e6044f71 BVA |
2620 | * state, only power management requests will be accepted, all others will |
2621 | * be deferred. | |
1da177e4 LT |
2622 | * |
2623 | * Must be called with user context, may sleep. | |
2624 | * | |
2625 | * Returns zero if unsuccessful or an error if not. | |
eb44820c | 2626 | */ |
1da177e4 LT |
2627 | int |
2628 | scsi_device_quiesce(struct scsi_device *sdev) | |
2629 | { | |
3a0a5299 | 2630 | struct request_queue *q = sdev->request_queue; |
0db6ca8a BVA |
2631 | int err; |
2632 | ||
3a0a5299 BVA |
2633 | /* |
2634 | * It is allowed to call scsi_device_quiesce() multiple times from | |
2635 | * the same context but concurrent scsi_device_quiesce() calls are | |
2636 | * not allowed. | |
2637 | */ | |
2638 | WARN_ON_ONCE(sdev->quiesced_by && sdev->quiesced_by != current); | |
2639 | ||
cd84a62e BVA |
2640 | if (sdev->quiesced_by == current) |
2641 | return 0; | |
2642 | ||
2643 | blk_set_pm_only(q); | |
3a0a5299 BVA |
2644 | |
2645 | blk_mq_freeze_queue(q); | |
2646 | /* | |
cd84a62e | 2647 | * Ensure that the effect of blk_set_pm_only() will be visible |
3a0a5299 BVA |
2648 | * for percpu_ref_tryget() callers that occur after the queue |
2649 | * unfreeze even if the queue was already frozen before this function | |
2650 | * was called. See also https://lwn.net/Articles/573497/. | |
2651 | */ | |
2652 | synchronize_rcu(); | |
2653 | blk_mq_unfreeze_queue(q); | |
2654 | ||
0db6ca8a BVA |
2655 | mutex_lock(&sdev->state_mutex); |
2656 | err = scsi_device_set_state(sdev, SDEV_QUIESCE); | |
3a0a5299 BVA |
2657 | if (err == 0) |
2658 | sdev->quiesced_by = current; | |
2659 | else | |
cd84a62e | 2660 | blk_clear_pm_only(q); |
0db6ca8a BVA |
2661 | mutex_unlock(&sdev->state_mutex); |
2662 | ||
3a0a5299 | 2663 | return err; |
1da177e4 LT |
2664 | } |
2665 | EXPORT_SYMBOL(scsi_device_quiesce); | |
2666 | ||
2667 | /** | |
2668 | * scsi_device_resume - Restart user issued commands to a quiesced device. | |
2669 | * @sdev: scsi device to resume. | |
2670 | * | |
2671 | * Moves the device from quiesced back to running and restarts the | |
2672 | * queues. | |
2673 | * | |
2674 | * Must be called with user context, may sleep. | |
eb44820c | 2675 | */ |
a7a20d10 | 2676 | void scsi_device_resume(struct scsi_device *sdev) |
1da177e4 | 2677 | { |
a7a20d10 DW |
2678 | /* check if the device state was mutated prior to resume, and if |
2679 | * so assume the state is being managed elsewhere (for example | |
2680 | * device deleted during suspend) | |
2681 | */ | |
0db6ca8a | 2682 | mutex_lock(&sdev->state_mutex); |
e6044f71 BVA |
2683 | if (sdev->sdev_state == SDEV_QUIESCE) |
2684 | scsi_device_set_state(sdev, SDEV_RUNNING); | |
17605afa BVA |
2685 | if (sdev->quiesced_by) { |
2686 | sdev->quiesced_by = NULL; | |
2687 | blk_clear_pm_only(sdev->request_queue); | |
2688 | } | |
0db6ca8a | 2689 | mutex_unlock(&sdev->state_mutex); |
1da177e4 LT |
2690 | } |
2691 | EXPORT_SYMBOL(scsi_device_resume); | |
2692 | ||
2693 | static void | |
2694 | device_quiesce_fn(struct scsi_device *sdev, void *data) | |
2695 | { | |
2696 | scsi_device_quiesce(sdev); | |
2697 | } | |
2698 | ||
2699 | void | |
2700 | scsi_target_quiesce(struct scsi_target *starget) | |
2701 | { | |
2702 | starget_for_each_device(starget, NULL, device_quiesce_fn); | |
2703 | } | |
2704 | EXPORT_SYMBOL(scsi_target_quiesce); | |
2705 | ||
2706 | static void | |
2707 | device_resume_fn(struct scsi_device *sdev, void *data) | |
2708 | { | |
2709 | scsi_device_resume(sdev); | |
2710 | } | |
2711 | ||
2712 | void | |
2713 | scsi_target_resume(struct scsi_target *starget) | |
2714 | { | |
2715 | starget_for_each_device(starget, NULL, device_resume_fn); | |
2716 | } | |
2717 | EXPORT_SYMBOL(scsi_target_resume); | |
2718 | ||
d2b9f12b ML |
2719 | static int __scsi_internal_device_block_nowait(struct scsi_device *sdev) |
2720 | { | |
2721 | if (scsi_device_set_state(sdev, SDEV_BLOCK)) | |
2722 | return scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); | |
2723 | ||
2724 | return 0; | |
2725 | } | |
2726 | ||
93542fbf ML |
2727 | void scsi_start_queue(struct scsi_device *sdev) |
2728 | { | |
2729 | if (cmpxchg(&sdev->queue_stopped, 1, 0)) | |
2730 | blk_mq_unquiesce_queue(sdev->request_queue); | |
2731 | } | |
2732 | ||
d7035b73 | 2733 | static void scsi_stop_queue(struct scsi_device *sdev) |
93542fbf ML |
2734 | { |
2735 | /* | |
2736 | * The atomic variable of ->queue_stopped covers that | |
2737 | * blk_mq_quiesce_queue* is balanced with blk_mq_unquiesce_queue. | |
2738 | * | |
d7035b73 | 2739 | * The caller needs to wait until quiesce is done. |
93542fbf | 2740 | */ |
d7035b73 MW |
2741 | if (!cmpxchg(&sdev->queue_stopped, 0, 1)) |
2742 | blk_mq_quiesce_queue_nowait(sdev->request_queue); | |
93542fbf ML |
2743 | } |
2744 | ||
1da177e4 | 2745 | /** |
551eb598 BVA |
2746 | * scsi_internal_device_block_nowait - try to transition to the SDEV_BLOCK state |
2747 | * @sdev: device to block | |
1da177e4 | 2748 | * |
551eb598 | 2749 | * Pause SCSI command processing on the specified device. Does not sleep. |
1da177e4 | 2750 | * |
551eb598 | 2751 | * Returns zero if successful or a negative error code upon failure. |
669f0441 | 2752 | * |
551eb598 BVA |
2753 | * Notes: |
2754 | * This routine transitions the device to the SDEV_BLOCK state (which must be | |
2755 | * a legal transition). When the device is in this state, command processing | |
2756 | * is paused until the device leaves the SDEV_BLOCK state. See also | |
2757 | * scsi_internal_device_unblock_nowait(). | |
eb44820c | 2758 | */ |
551eb598 | 2759 | int scsi_internal_device_block_nowait(struct scsi_device *sdev) |
1da177e4 | 2760 | { |
d2b9f12b | 2761 | int ret = __scsi_internal_device_block_nowait(sdev); |
1da177e4 | 2762 | |
4c7b4d63 | 2763 | /* |
1da177e4 LT |
2764 | * The device has transitioned to SDEV_BLOCK. Stop the |
2765 | * block layer from calling the midlayer with this device's | |
4c7b4d63 | 2766 | * request queue. |
1da177e4 | 2767 | */ |
d2b9f12b | 2768 | if (!ret) |
d7035b73 | 2769 | scsi_stop_queue(sdev); |
d2b9f12b | 2770 | return ret; |
1da177e4 | 2771 | } |
551eb598 BVA |
2772 | EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait); |
2773 | ||
1da177e4 | 2774 | /** |
c5e46f7a | 2775 | * scsi_device_block - try to transition to the SDEV_BLOCK state |
551eb598 | 2776 | * @sdev: device to block |
c5e46f7a | 2777 | * @data: dummy argument, ignored |
551eb598 | 2778 | * |
e20fff8a MW |
2779 | * Pause SCSI command processing on the specified device. Callers must wait |
2780 | * until all ongoing scsi_queue_rq() calls have finished after this function | |
2781 | * returns. | |
1da177e4 | 2782 | * |
551eb598 BVA |
2783 | * Note: |
2784 | * This routine transitions the device to the SDEV_BLOCK state (which must be | |
2785 | * a legal transition). When the device is in this state, command processing | |
2786 | * is paused until the device leaves the SDEV_BLOCK state. See also | |
2787 | * scsi_internal_device_unblock(). | |
eb44820c | 2788 | */ |
c5e46f7a | 2789 | static void scsi_device_block(struct scsi_device *sdev, void *data) |
1da177e4 | 2790 | { |
551eb598 | 2791 | int err; |
6d7160c7 | 2792 | enum scsi_device_state state; |
551eb598 | 2793 | |
0db6ca8a | 2794 | mutex_lock(&sdev->state_mutex); |
d2b9f12b | 2795 | err = __scsi_internal_device_block_nowait(sdev); |
6d7160c7 | 2796 | state = sdev->sdev_state; |
f664a3cc | 2797 | if (err == 0) |
d7035b73 MW |
2798 | /* |
2799 | * scsi_stop_queue() must be called with the state_mutex | |
2800 | * held. Otherwise a simultaneous scsi_start_queue() call | |
2801 | * might unquiesce the queue before we quiesce it. | |
2802 | */ | |
2803 | scsi_stop_queue(sdev); | |
e20fff8a | 2804 | |
0db6ca8a BVA |
2805 | mutex_unlock(&sdev->state_mutex); |
2806 | ||
6d7160c7 MW |
2807 | WARN_ONCE(err, "%s: failed to block %s in state %d\n", |
2808 | __func__, dev_name(&sdev->sdev_gendev), state); | |
551eb598 | 2809 | } |
4c7b4d63 | 2810 | |
1da177e4 | 2811 | /** |
43f7571b | 2812 | * scsi_internal_device_unblock_nowait - resume a device after a block request |
1da177e4 | 2813 | * @sdev: device to resume |
43f7571b | 2814 | * @new_state: state to set the device to after unblocking |
1da177e4 | 2815 | * |
43f7571b BVA |
2816 | * Restart the device queue for a previously suspended SCSI device. Does not |
2817 | * sleep. | |
1da177e4 | 2818 | * |
43f7571b | 2819 | * Returns zero if successful or a negative error code upon failure. |
1da177e4 | 2820 | * |
43f7571b BVA |
2821 | * Notes: |
2822 | * This routine transitions the device to the SDEV_RUNNING state or to one of | |
2823 | * the offline states (which must be a legal transition) allowing the midlayer | |
2824 | * to goose the queue for this device. | |
eb44820c | 2825 | */ |
43f7571b BVA |
2826 | int scsi_internal_device_unblock_nowait(struct scsi_device *sdev, |
2827 | enum scsi_device_state new_state) | |
1da177e4 | 2828 | { |
09addb1d BVA |
2829 | switch (new_state) { |
2830 | case SDEV_RUNNING: | |
2831 | case SDEV_TRANSPORT_OFFLINE: | |
2832 | break; | |
2833 | default: | |
2834 | return -EINVAL; | |
2835 | } | |
2836 | ||
5d9fb5cc MC |
2837 | /* |
2838 | * Try to transition the scsi device to SDEV_RUNNING or one of the | |
2839 | * offlined states and goose the device queue if successful. | |
1da177e4 | 2840 | */ |
8cd1ec78 HR |
2841 | switch (sdev->sdev_state) { |
2842 | case SDEV_BLOCK: | |
2843 | case SDEV_TRANSPORT_OFFLINE: | |
5d9fb5cc | 2844 | sdev->sdev_state = new_state; |
8cd1ec78 HR |
2845 | break; |
2846 | case SDEV_CREATED_BLOCK: | |
5d9fb5cc MC |
2847 | if (new_state == SDEV_TRANSPORT_OFFLINE || |
2848 | new_state == SDEV_OFFLINE) | |
2849 | sdev->sdev_state = new_state; | |
2850 | else | |
2851 | sdev->sdev_state = SDEV_CREATED; | |
8cd1ec78 HR |
2852 | break; |
2853 | case SDEV_CANCEL: | |
2854 | case SDEV_OFFLINE: | |
2855 | break; | |
2856 | default: | |
5c10e63c | 2857 | return -EINVAL; |
8cd1ec78 | 2858 | } |
66483a4a | 2859 | scsi_start_queue(sdev); |
1da177e4 LT |
2860 | |
2861 | return 0; | |
2862 | } | |
43f7571b BVA |
2863 | EXPORT_SYMBOL_GPL(scsi_internal_device_unblock_nowait); |
2864 | ||
2865 | /** | |
2866 | * scsi_internal_device_unblock - resume a device after a block request | |
2867 | * @sdev: device to resume | |
2868 | * @new_state: state to set the device to after unblocking | |
2869 | * | |
2870 | * Restart the device queue for a previously suspended SCSI device. May sleep. | |
2871 | * | |
2872 | * Returns zero if successful or a negative error code upon failure. | |
2873 | * | |
2874 | * Notes: | |
2875 | * This routine transitions the device to the SDEV_RUNNING state or to one of | |
2876 | * the offline states (which must be a legal transition) allowing the midlayer | |
2877 | * to goose the queue for this device. | |
2878 | */ | |
2879 | static int scsi_internal_device_unblock(struct scsi_device *sdev, | |
2880 | enum scsi_device_state new_state) | |
2881 | { | |
0db6ca8a BVA |
2882 | int ret; |
2883 | ||
2884 | mutex_lock(&sdev->state_mutex); | |
2885 | ret = scsi_internal_device_unblock_nowait(sdev, new_state); | |
2886 | mutex_unlock(&sdev->state_mutex); | |
2887 | ||
2888 | return ret; | |
43f7571b | 2889 | } |
1da177e4 | 2890 | |
1da177e4 LT |
2891 | static int |
2892 | target_block(struct device *dev, void *data) | |
2893 | { | |
2894 | if (scsi_is_target_device(dev)) | |
2895 | starget_for_each_device(to_scsi_target(dev), NULL, | |
c5e46f7a | 2896 | scsi_device_block); |
1da177e4 LT |
2897 | return 0; |
2898 | } | |
2899 | ||
31950192 MW |
2900 | /** |
2901 | * scsi_block_targets - transition all SCSI child devices to SDEV_BLOCK state | |
2902 | * @dev: a parent device of one or more scsi_target devices | |
2903 | * @shost: the Scsi_Host to which this device belongs | |
2904 | * | |
2905 | * Iterate over all children of @dev, which should be scsi_target devices, | |
2906 | * and switch all subordinate scsi devices to SDEV_BLOCK state. Wait for | |
2907 | * ongoing scsi_queue_rq() calls to finish. May sleep. | |
2908 | * | |
2909 | * Note: | |
2910 | * @dev must not itself be a scsi_target device. | |
2911 | */ | |
1da177e4 | 2912 | void |
31950192 | 2913 | scsi_block_targets(struct Scsi_Host *shost, struct device *dev) |
1da177e4 | 2914 | { |
31950192 MW |
2915 | WARN_ON_ONCE(scsi_is_target_device(dev)); |
2916 | device_for_each_child(dev, NULL, target_block); | |
e20fff8a | 2917 | blk_mq_wait_quiesce_done(&shost->tag_set); |
1da177e4 | 2918 | } |
31950192 | 2919 | EXPORT_SYMBOL_GPL(scsi_block_targets); |
1da177e4 LT |
2920 | |
2921 | static void | |
2922 | device_unblock(struct scsi_device *sdev, void *data) | |
2923 | { | |
5d9fb5cc | 2924 | scsi_internal_device_unblock(sdev, *(enum scsi_device_state *)data); |
1da177e4 LT |
2925 | } |
2926 | ||
2927 | static int | |
2928 | target_unblock(struct device *dev, void *data) | |
2929 | { | |
2930 | if (scsi_is_target_device(dev)) | |
5d9fb5cc | 2931 | starget_for_each_device(to_scsi_target(dev), data, |
1da177e4 LT |
2932 | device_unblock); |
2933 | return 0; | |
2934 | } | |
2935 | ||
2936 | void | |
5d9fb5cc | 2937 | scsi_target_unblock(struct device *dev, enum scsi_device_state new_state) |
1da177e4 LT |
2938 | { |
2939 | if (scsi_is_target_device(dev)) | |
5d9fb5cc | 2940 | starget_for_each_device(to_scsi_target(dev), &new_state, |
1da177e4 LT |
2941 | device_unblock); |
2942 | else | |
5d9fb5cc | 2943 | device_for_each_child(dev, &new_state, target_unblock); |
1da177e4 LT |
2944 | } |
2945 | EXPORT_SYMBOL_GPL(scsi_target_unblock); | |
cdb8c2a6 | 2946 | |
c854bcdf BVA |
2947 | /** |
2948 | * scsi_host_block - Try to transition all logical units to the SDEV_BLOCK state | |
2949 | * @shost: device to block | |
2950 | * | |
2951 | * Pause SCSI command processing for all logical units associated with the SCSI | |
2952 | * host and wait until pending scsi_queue_rq() calls have finished. | |
2953 | * | |
2954 | * Returns zero if successful or a negative error code upon failure. | |
2955 | */ | |
2bb95584 HR |
2956 | int |
2957 | scsi_host_block(struct Scsi_Host *shost) | |
2958 | { | |
2959 | struct scsi_device *sdev; | |
c854bcdf | 2960 | int ret; |
2bb95584 | 2961 | |
f983622a ML |
2962 | /* |
2963 | * Call scsi_internal_device_block_nowait so we can avoid | |
2964 | * calling synchronize_rcu() for each LUN. | |
2965 | */ | |
2bb95584 | 2966 | shost_for_each_device(sdev, shost) { |
f983622a ML |
2967 | mutex_lock(&sdev->state_mutex); |
2968 | ret = scsi_internal_device_block_nowait(sdev); | |
2969 | mutex_unlock(&sdev->state_mutex); | |
f30785db YB |
2970 | if (ret) { |
2971 | scsi_device_put(sdev); | |
c854bcdf | 2972 | return ret; |
f30785db | 2973 | } |
2bb95584 | 2974 | } |
f983622a | 2975 | |
b125bb99 BVA |
2976 | /* Wait for ongoing scsi_queue_rq() calls to finish. */ |
2977 | blk_mq_wait_quiesce_done(&shost->tag_set); | |
f983622a | 2978 | |
c854bcdf | 2979 | return 0; |
2bb95584 HR |
2980 | } |
2981 | EXPORT_SYMBOL_GPL(scsi_host_block); | |
2982 | ||
2983 | int | |
2984 | scsi_host_unblock(struct Scsi_Host *shost, int new_state) | |
2985 | { | |
2986 | struct scsi_device *sdev; | |
2987 | int ret = 0; | |
2988 | ||
2989 | shost_for_each_device(sdev, shost) { | |
2990 | ret = scsi_internal_device_unblock(sdev, new_state); | |
4dea170f YB |
2991 | if (ret) { |
2992 | scsi_device_put(sdev); | |
2bb95584 | 2993 | break; |
4dea170f | 2994 | } |
2bb95584 HR |
2995 | } |
2996 | return ret; | |
2997 | } | |
2998 | EXPORT_SYMBOL_GPL(scsi_host_unblock); | |
2999 | ||
cdb8c2a6 GL |
3000 | /** |
3001 | * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt | |
eb44820c | 3002 | * @sgl: scatter-gather list |
cdb8c2a6 GL |
3003 | * @sg_count: number of segments in sg |
3004 | * @offset: offset in bytes into sg, on return offset into the mapped area | |
3005 | * @len: bytes to map, on return number of bytes mapped | |
3006 | * | |
3007 | * Returns virtual address of the start of the mapped page | |
3008 | */ | |
c6132da1 | 3009 | void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count, |
cdb8c2a6 GL |
3010 | size_t *offset, size_t *len) |
3011 | { | |
3012 | int i; | |
3013 | size_t sg_len = 0, len_complete = 0; | |
c6132da1 | 3014 | struct scatterlist *sg; |
cdb8c2a6 GL |
3015 | struct page *page; |
3016 | ||
22cfefb5 AM |
3017 | WARN_ON(!irqs_disabled()); |
3018 | ||
c6132da1 | 3019 | for_each_sg(sgl, sg, sg_count, i) { |
cdb8c2a6 | 3020 | len_complete = sg_len; /* Complete sg-entries */ |
c6132da1 | 3021 | sg_len += sg->length; |
cdb8c2a6 GL |
3022 | if (sg_len > *offset) |
3023 | break; | |
3024 | } | |
3025 | ||
3026 | if (unlikely(i == sg_count)) { | |
169e1a2a AM |
3027 | printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, " |
3028 | "elements %d\n", | |
cadbd4a5 | 3029 | __func__, sg_len, *offset, sg_count); |
cdb8c2a6 GL |
3030 | WARN_ON(1); |
3031 | return NULL; | |
3032 | } | |
3033 | ||
3034 | /* Offset starting from the beginning of first page in this sg-entry */ | |
c6132da1 | 3035 | *offset = *offset - len_complete + sg->offset; |
cdb8c2a6 GL |
3036 | |
3037 | /* Assumption: contiguous pages can be accessed as "page + i" */ | |
45711f1a | 3038 | page = nth_page(sg_page(sg), (*offset >> PAGE_SHIFT)); |
cdb8c2a6 GL |
3039 | *offset &= ~PAGE_MASK; |
3040 | ||
3041 | /* Bytes in this sg-entry from *offset to the end of the page */ | |
3042 | sg_len = PAGE_SIZE - *offset; | |
3043 | if (*len > sg_len) | |
3044 | *len = sg_len; | |
3045 | ||
77dfce07 | 3046 | return kmap_atomic(page); |
cdb8c2a6 GL |
3047 | } |
3048 | EXPORT_SYMBOL(scsi_kmap_atomic_sg); | |
3049 | ||
3050 | /** | |
eb44820c | 3051 | * scsi_kunmap_atomic_sg - atomically unmap a virtual address, previously mapped with scsi_kmap_atomic_sg |
cdb8c2a6 GL |
3052 | * @virt: virtual address to be unmapped |
3053 | */ | |
3054 | void scsi_kunmap_atomic_sg(void *virt) | |
3055 | { | |
77dfce07 | 3056 | kunmap_atomic(virt); |
cdb8c2a6 GL |
3057 | } |
3058 | EXPORT_SYMBOL(scsi_kunmap_atomic_sg); | |
6f4c827e AL |
3059 | |
3060 | void sdev_disable_disk_events(struct scsi_device *sdev) | |
3061 | { | |
3062 | atomic_inc(&sdev->disk_events_disable_depth); | |
3063 | } | |
3064 | EXPORT_SYMBOL(sdev_disable_disk_events); | |
3065 | ||
3066 | void sdev_enable_disk_events(struct scsi_device *sdev) | |
3067 | { | |
3068 | if (WARN_ON_ONCE(atomic_read(&sdev->disk_events_disable_depth) <= 0)) | |
3069 | return; | |
3070 | atomic_dec(&sdev->disk_events_disable_depth); | |
3071 | } | |
3072 | EXPORT_SYMBOL(sdev_enable_disk_events); | |
9983bed3 | 3073 | |
2e4209b3 MW |
3074 | static unsigned char designator_prio(const unsigned char *d) |
3075 | { | |
3076 | if (d[1] & 0x30) | |
3077 | /* not associated with LUN */ | |
3078 | return 0; | |
3079 | ||
3080 | if (d[3] == 0) | |
3081 | /* invalid length */ | |
3082 | return 0; | |
3083 | ||
3084 | /* | |
3085 | * Order of preference for lun descriptor: | |
3086 | * - SCSI name string | |
3087 | * - NAA IEEE Registered Extended | |
3088 | * - EUI-64 based 16-byte | |
3089 | * - EUI-64 based 12-byte | |
3090 | * - NAA IEEE Registered | |
3091 | * - NAA IEEE Extended | |
3092 | * - EUI-64 based 8-byte | |
3093 | * - SCSI name string (truncated) | |
3094 | * - T10 Vendor ID | |
3095 | * as longer descriptors reduce the likelyhood | |
3096 | * of identification clashes. | |
3097 | */ | |
3098 | ||
3099 | switch (d[1] & 0xf) { | |
3100 | case 8: | |
3101 | /* SCSI name string, variable-length UTF-8 */ | |
3102 | return 9; | |
3103 | case 3: | |
3104 | switch (d[4] >> 4) { | |
3105 | case 6: | |
3106 | /* NAA registered extended */ | |
3107 | return 8; | |
3108 | case 5: | |
3109 | /* NAA registered */ | |
3110 | return 5; | |
3111 | case 4: | |
3112 | /* NAA extended */ | |
3113 | return 4; | |
3114 | case 3: | |
3115 | /* NAA locally assigned */ | |
3116 | return 1; | |
3117 | default: | |
3118 | break; | |
3119 | } | |
3120 | break; | |
3121 | case 2: | |
3122 | switch (d[3]) { | |
3123 | case 16: | |
3124 | /* EUI64-based, 16 byte */ | |
3125 | return 7; | |
3126 | case 12: | |
3127 | /* EUI64-based, 12 byte */ | |
3128 | return 6; | |
3129 | case 8: | |
3130 | /* EUI64-based, 8 byte */ | |
3131 | return 3; | |
3132 | default: | |
3133 | break; | |
3134 | } | |
3135 | break; | |
3136 | case 1: | |
3137 | /* T10 vendor ID */ | |
3138 | return 1; | |
3139 | default: | |
3140 | break; | |
3141 | } | |
3142 | ||
3143 | return 0; | |
3144 | } | |
3145 | ||
9983bed3 HR |
3146 | /** |
3147 | * scsi_vpd_lun_id - return a unique device identification | |
3148 | * @sdev: SCSI device | |
3149 | * @id: buffer for the identification | |
3150 | * @id_len: length of the buffer | |
3151 | * | |
3152 | * Copies a unique device identification into @id based | |
3153 | * on the information in the VPD page 0x83 of the device. | |
3154 | * The string will be formatted as a SCSI name string. | |
3155 | * | |
3156 | * Returns the length of the identification or error on failure. | |
3157 | * If the identifier is longer than the supplied buffer the actual | |
3158 | * identifier length is returned and the buffer is not zero-padded. | |
3159 | */ | |
3160 | int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len) | |
3161 | { | |
2e4209b3 | 3162 | u8 cur_id_prio = 0; |
9983bed3 | 3163 | u8 cur_id_size = 0; |
ccf1e004 BVA |
3164 | const unsigned char *d, *cur_id_str; |
3165 | const struct scsi_vpd *vpd_pg83; | |
9983bed3 HR |
3166 | int id_size = -EINVAL; |
3167 | ||
3168 | rcu_read_lock(); | |
3169 | vpd_pg83 = rcu_dereference(sdev->vpd_pg83); | |
3170 | if (!vpd_pg83) { | |
3171 | rcu_read_unlock(); | |
3172 | return -ENXIO; | |
3173 | } | |
3174 | ||
9983bed3 HR |
3175 | /* The id string must be at least 20 bytes + terminating NULL byte */ |
3176 | if (id_len < 21) { | |
3177 | rcu_read_unlock(); | |
3178 | return -EINVAL; | |
3179 | } | |
3180 | ||
3181 | memset(id, 0, id_len); | |
16d6317e MW |
3182 | for (d = vpd_pg83->data + 4; |
3183 | d < vpd_pg83->data + vpd_pg83->len; | |
3184 | d += d[3] + 4) { | |
2e4209b3 MW |
3185 | u8 prio = designator_prio(d); |
3186 | ||
3187 | if (prio == 0 || cur_id_prio > prio) | |
16d6317e | 3188 | continue; |
9983bed3 HR |
3189 | |
3190 | switch (d[1] & 0xf) { | |
d230823a HR |
3191 | case 0x1: |
3192 | /* T10 Vendor ID */ | |
3193 | if (cur_id_size > d[3]) | |
3194 | break; | |
2e4209b3 | 3195 | cur_id_prio = prio; |
d230823a HR |
3196 | cur_id_size = d[3]; |
3197 | if (cur_id_size + 4 > id_len) | |
3198 | cur_id_size = id_len - 4; | |
3199 | cur_id_str = d + 4; | |
d230823a HR |
3200 | id_size = snprintf(id, id_len, "t10.%*pE", |
3201 | cur_id_size, cur_id_str); | |
3202 | break; | |
9983bed3 HR |
3203 | case 0x2: |
3204 | /* EUI-64 */ | |
2e4209b3 | 3205 | cur_id_prio = prio; |
9983bed3 HR |
3206 | cur_id_size = d[3]; |
3207 | cur_id_str = d + 4; | |
9983bed3 HR |
3208 | switch (cur_id_size) { |
3209 | case 8: | |
3210 | id_size = snprintf(id, id_len, | |
3211 | "eui.%8phN", | |
3212 | cur_id_str); | |
3213 | break; | |
3214 | case 12: | |
3215 | id_size = snprintf(id, id_len, | |
3216 | "eui.%12phN", | |
3217 | cur_id_str); | |
3218 | break; | |
3219 | case 16: | |
3220 | id_size = snprintf(id, id_len, | |
3221 | "eui.%16phN", | |
3222 | cur_id_str); | |
3223 | break; | |
3224 | default: | |
9983bed3 HR |
3225 | break; |
3226 | } | |
3227 | break; | |
3228 | case 0x3: | |
3229 | /* NAA */ | |
2e4209b3 | 3230 | cur_id_prio = prio; |
9983bed3 HR |
3231 | cur_id_size = d[3]; |
3232 | cur_id_str = d + 4; | |
9983bed3 HR |
3233 | switch (cur_id_size) { |
3234 | case 8: | |
3235 | id_size = snprintf(id, id_len, | |
3236 | "naa.%8phN", | |
3237 | cur_id_str); | |
3238 | break; | |
3239 | case 16: | |
3240 | id_size = snprintf(id, id_len, | |
3241 | "naa.%16phN", | |
3242 | cur_id_str); | |
3243 | break; | |
3244 | default: | |
9983bed3 HR |
3245 | break; |
3246 | } | |
3247 | break; | |
3248 | case 0x8: | |
3249 | /* SCSI name string */ | |
2e4209b3 | 3250 | if (cur_id_size > d[3]) |
9983bed3 HR |
3251 | break; |
3252 | /* Prefer others for truncated descriptor */ | |
2e4209b3 MW |
3253 | if (d[3] > id_len) { |
3254 | prio = 2; | |
3255 | if (cur_id_prio > prio) | |
3256 | break; | |
3257 | } | |
3258 | cur_id_prio = prio; | |
9983bed3 HR |
3259 | cur_id_size = id_size = d[3]; |
3260 | cur_id_str = d + 4; | |
9983bed3 HR |
3261 | if (cur_id_size >= id_len) |
3262 | cur_id_size = id_len - 1; | |
3263 | memcpy(id, cur_id_str, cur_id_size); | |
9983bed3 HR |
3264 | break; |
3265 | default: | |
3266 | break; | |
3267 | } | |
9983bed3 HR |
3268 | } |
3269 | rcu_read_unlock(); | |
3270 | ||
3271 | return id_size; | |
3272 | } | |
3273 | EXPORT_SYMBOL(scsi_vpd_lun_id); | |
a8aa3978 HR |
3274 | |
3275 | /* | |
3276 | * scsi_vpd_tpg_id - return a target port group identifier | |
3277 | * @sdev: SCSI device | |
3278 | * | |
3279 | * Returns the Target Port Group identifier from the information | |
3280 | * froom VPD page 0x83 of the device. | |
3281 | * | |
3282 | * Returns the identifier or error on failure. | |
3283 | */ | |
3284 | int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id) | |
3285 | { | |
ccf1e004 BVA |
3286 | const unsigned char *d; |
3287 | const struct scsi_vpd *vpd_pg83; | |
a8aa3978 HR |
3288 | int group_id = -EAGAIN, rel_port = -1; |
3289 | ||
3290 | rcu_read_lock(); | |
3291 | vpd_pg83 = rcu_dereference(sdev->vpd_pg83); | |
3292 | if (!vpd_pg83) { | |
3293 | rcu_read_unlock(); | |
3294 | return -ENXIO; | |
3295 | } | |
3296 | ||
ccf1e004 BVA |
3297 | d = vpd_pg83->data + 4; |
3298 | while (d < vpd_pg83->data + vpd_pg83->len) { | |
a8aa3978 HR |
3299 | switch (d[1] & 0xf) { |
3300 | case 0x4: | |
3301 | /* Relative target port */ | |
3302 | rel_port = get_unaligned_be16(&d[6]); | |
3303 | break; | |
3304 | case 0x5: | |
3305 | /* Target port group */ | |
3306 | group_id = get_unaligned_be16(&d[6]); | |
3307 | break; | |
3308 | default: | |
3309 | break; | |
3310 | } | |
3311 | d += d[3] + 4; | |
3312 | } | |
3313 | rcu_read_unlock(); | |
3314 | ||
3315 | if (group_id >= 0 && rel_id && rel_port != -1) | |
3316 | *rel_id = rel_port; | |
3317 | ||
3318 | return group_id; | |
3319 | } | |
3320 | EXPORT_SYMBOL(scsi_vpd_tpg_id); | |
f2b1e9c6 HR |
3321 | |
3322 | /** | |
3323 | * scsi_build_sense - build sense data for a command | |
3324 | * @scmd: scsi command for which the sense should be formatted | |
3325 | * @desc: Sense format (non-zero == descriptor format, | |
3326 | * 0 == fixed format) | |
3327 | * @key: Sense key | |
3328 | * @asc: Additional sense code | |
3329 | * @ascq: Additional sense code qualifier | |
3330 | * | |
3331 | **/ | |
3332 | void scsi_build_sense(struct scsi_cmnd *scmd, int desc, u8 key, u8 asc, u8 ascq) | |
3333 | { | |
3334 | scsi_build_sense_buffer(desc, scmd->sense_buffer, key, asc, ascq); | |
464a00c9 | 3335 | scmd->result = SAM_STAT_CHECK_CONDITION; |
f2b1e9c6 HR |
3336 | } |
3337 | EXPORT_SYMBOL_GPL(scsi_build_sense); |