Commit | Line | Data |
---|---|---|
3dcf60bc | 1 | // SPDX-License-Identifier: GPL-2.0 |
75bb4625 JA |
2 | /* |
3 | * Block multiqueue core code | |
4 | * | |
5 | * Copyright (C) 2013-2014 Jens Axboe | |
6 | * Copyright (C) 2013-2014 Christoph Hellwig | |
7 | */ | |
320ae51f JA |
8 | #include <linux/kernel.h> |
9 | #include <linux/module.h> | |
10 | #include <linux/backing-dev.h> | |
11 | #include <linux/bio.h> | |
12 | #include <linux/blkdev.h> | |
fe45e630 | 13 | #include <linux/blk-integrity.h> |
f75782e4 | 14 | #include <linux/kmemleak.h> |
320ae51f JA |
15 | #include <linux/mm.h> |
16 | #include <linux/init.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/workqueue.h> | |
19 | #include <linux/smp.h> | |
e41d12f5 | 20 | #include <linux/interrupt.h> |
320ae51f | 21 | #include <linux/llist.h> |
320ae51f JA |
22 | #include <linux/cpu.h> |
23 | #include <linux/cache.h> | |
24 | #include <linux/sched/sysctl.h> | |
105ab3d8 | 25 | #include <linux/sched/topology.h> |
174cd4b1 | 26 | #include <linux/sched/signal.h> |
320ae51f | 27 | #include <linux/delay.h> |
aedcd72f | 28 | #include <linux/crash_dump.h> |
88c7b2b7 | 29 | #include <linux/prefetch.h> |
a892c8d5 | 30 | #include <linux/blk-crypto.h> |
82d981d4 | 31 | #include <linux/part_stat.h> |
320ae51f JA |
32 | |
33 | #include <trace/events/block.h> | |
34 | ||
54d4e6ab | 35 | #include <linux/t10-pi.h> |
320ae51f JA |
36 | #include "blk.h" |
37 | #include "blk-mq.h" | |
9c1051aa | 38 | #include "blk-mq-debugfs.h" |
986d413b | 39 | #include "blk-pm.h" |
cf43e6be | 40 | #include "blk-stat.h" |
bd166ef1 | 41 | #include "blk-mq-sched.h" |
c1c80384 | 42 | #include "blk-rq-qos.h" |
82b74cac | 43 | #include "blk-ioprio.h" |
320ae51f | 44 | |
f9ab4918 | 45 | static DEFINE_PER_CPU(struct llist_head, blk_cpu_done); |
c3077b5d | 46 | |
710fa378 | 47 | static void blk_mq_insert_request(struct request *rq, blk_insert_t flags); |
360f2648 CH |
48 | static void blk_mq_request_bypass_insert(struct request *rq, |
49 | blk_insert_t flags); | |
94aa228c CH |
50 | static void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, |
51 | struct list_head *list); | |
f6c80cff KB |
52 | static int blk_hctx_poll(struct request_queue *q, struct blk_mq_hw_ctx *hctx, |
53 | struct io_comp_batch *iob, unsigned int flags); | |
3e08773c | 54 | |
320ae51f | 55 | /* |
85fae294 YY |
56 | * Check if any of the ctx, dispatch list or elevator |
57 | * have pending work in this hardware queue. | |
320ae51f | 58 | */ |
79f720a7 | 59 | static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx) |
320ae51f | 60 | { |
79f720a7 JA |
61 | return !list_empty_careful(&hctx->dispatch) || |
62 | sbitmap_any_bit_set(&hctx->ctx_map) || | |
bd166ef1 | 63 | blk_mq_sched_has_work(hctx); |
1429d7c9 JA |
64 | } |
65 | ||
320ae51f JA |
66 | /* |
67 | * Mark this ctx as having pending work in this hardware queue | |
68 | */ | |
69 | static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, | |
70 | struct blk_mq_ctx *ctx) | |
71 | { | |
f31967f0 JA |
72 | const int bit = ctx->index_hw[hctx->type]; |
73 | ||
74 | if (!sbitmap_test_bit(&hctx->ctx_map, bit)) | |
75 | sbitmap_set_bit(&hctx->ctx_map, bit); | |
1429d7c9 JA |
76 | } |
77 | ||
78 | static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, | |
79 | struct blk_mq_ctx *ctx) | |
80 | { | |
f31967f0 JA |
81 | const int bit = ctx->index_hw[hctx->type]; |
82 | ||
83 | sbitmap_clear_bit(&hctx->ctx_map, bit); | |
320ae51f JA |
84 | } |
85 | ||
f299b7c7 | 86 | struct mq_inflight { |
8446fe92 | 87 | struct block_device *part; |
a2e80f6f | 88 | unsigned int inflight[2]; |
f299b7c7 JA |
89 | }; |
90 | ||
2dd6532e | 91 | static bool blk_mq_check_inflight(struct request *rq, void *priv) |
f299b7c7 JA |
92 | { |
93 | struct mq_inflight *mi = priv; | |
94 | ||
b81c14ca HW |
95 | if (rq->part && blk_do_io_stat(rq) && |
96 | (!mi->part->bd_partno || rq->part == mi->part) && | |
b0d97557 | 97 | blk_mq_rq_state(rq) == MQ_RQ_IN_FLIGHT) |
bb4e6b14 | 98 | mi->inflight[rq_data_dir(rq)]++; |
7baa8572 JA |
99 | |
100 | return true; | |
f299b7c7 JA |
101 | } |
102 | ||
8446fe92 CH |
103 | unsigned int blk_mq_in_flight(struct request_queue *q, |
104 | struct block_device *part) | |
f299b7c7 | 105 | { |
a2e80f6f | 106 | struct mq_inflight mi = { .part = part }; |
f299b7c7 | 107 | |
f299b7c7 | 108 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi); |
e016b782 | 109 | |
a2e80f6f | 110 | return mi.inflight[0] + mi.inflight[1]; |
bf0ddaba OS |
111 | } |
112 | ||
8446fe92 CH |
113 | void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part, |
114 | unsigned int inflight[2]) | |
bf0ddaba | 115 | { |
a2e80f6f | 116 | struct mq_inflight mi = { .part = part }; |
bf0ddaba | 117 | |
bb4e6b14 | 118 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi); |
a2e80f6f PB |
119 | inflight[0] = mi.inflight[0]; |
120 | inflight[1] = mi.inflight[1]; | |
bf0ddaba OS |
121 | } |
122 | ||
1671d522 | 123 | void blk_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 124 | { |
7996a8b5 BL |
125 | mutex_lock(&q->mq_freeze_lock); |
126 | if (++q->mq_freeze_depth == 1) { | |
3ef28e83 | 127 | percpu_ref_kill(&q->q_usage_counter); |
7996a8b5 | 128 | mutex_unlock(&q->mq_freeze_lock); |
344e9ffc | 129 | if (queue_is_mq(q)) |
055f6e18 | 130 | blk_mq_run_hw_queues(q, false); |
7996a8b5 BL |
131 | } else { |
132 | mutex_unlock(&q->mq_freeze_lock); | |
cddd5d17 | 133 | } |
f3af020b | 134 | } |
1671d522 | 135 | EXPORT_SYMBOL_GPL(blk_freeze_queue_start); |
f3af020b | 136 | |
6bae363e | 137 | void blk_mq_freeze_queue_wait(struct request_queue *q) |
f3af020b | 138 | { |
3ef28e83 | 139 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter)); |
43a5e4e2 | 140 | } |
6bae363e | 141 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait); |
43a5e4e2 | 142 | |
f91328c4 KB |
143 | int blk_mq_freeze_queue_wait_timeout(struct request_queue *q, |
144 | unsigned long timeout) | |
145 | { | |
146 | return wait_event_timeout(q->mq_freeze_wq, | |
147 | percpu_ref_is_zero(&q->q_usage_counter), | |
148 | timeout); | |
149 | } | |
150 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait_timeout); | |
43a5e4e2 | 151 | |
f3af020b TH |
152 | /* |
153 | * Guarantee no request is in use, so we can change any data structure of | |
154 | * the queue afterward. | |
155 | */ | |
3ef28e83 | 156 | void blk_freeze_queue(struct request_queue *q) |
f3af020b | 157 | { |
3ef28e83 DW |
158 | /* |
159 | * In the !blk_mq case we are only calling this to kill the | |
160 | * q_usage_counter, otherwise this increases the freeze depth | |
161 | * and waits for it to return to zero. For this reason there is | |
162 | * no blk_unfreeze_queue(), and blk_freeze_queue() is not | |
163 | * exported to drivers as the only user for unfreeze is blk_mq. | |
164 | */ | |
1671d522 | 165 | blk_freeze_queue_start(q); |
f3af020b TH |
166 | blk_mq_freeze_queue_wait(q); |
167 | } | |
3ef28e83 DW |
168 | |
169 | void blk_mq_freeze_queue(struct request_queue *q) | |
170 | { | |
171 | /* | |
172 | * ...just an alias to keep freeze and unfreeze actions balanced | |
173 | * in the blk_mq_* namespace | |
174 | */ | |
175 | blk_freeze_queue(q); | |
176 | } | |
c761d96b | 177 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue); |
f3af020b | 178 | |
aec89dc5 | 179 | void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic) |
320ae51f | 180 | { |
7996a8b5 | 181 | mutex_lock(&q->mq_freeze_lock); |
aec89dc5 CH |
182 | if (force_atomic) |
183 | q->q_usage_counter.data->force_atomic = true; | |
7996a8b5 BL |
184 | q->mq_freeze_depth--; |
185 | WARN_ON_ONCE(q->mq_freeze_depth < 0); | |
186 | if (!q->mq_freeze_depth) { | |
bdd63160 | 187 | percpu_ref_resurrect(&q->q_usage_counter); |
320ae51f | 188 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 189 | } |
7996a8b5 | 190 | mutex_unlock(&q->mq_freeze_lock); |
320ae51f | 191 | } |
aec89dc5 CH |
192 | |
193 | void blk_mq_unfreeze_queue(struct request_queue *q) | |
194 | { | |
195 | __blk_mq_unfreeze_queue(q, false); | |
196 | } | |
b4c6a028 | 197 | EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
320ae51f | 198 | |
852ec809 BVA |
199 | /* |
200 | * FIXME: replace the scsi_internal_device_*block_nowait() calls in the | |
201 | * mpt3sas driver such that this function can be removed. | |
202 | */ | |
203 | void blk_mq_quiesce_queue_nowait(struct request_queue *q) | |
204 | { | |
e70feb8b ML |
205 | unsigned long flags; |
206 | ||
207 | spin_lock_irqsave(&q->queue_lock, flags); | |
208 | if (!q->quiesce_depth++) | |
209 | blk_queue_flag_set(QUEUE_FLAG_QUIESCED, q); | |
210 | spin_unlock_irqrestore(&q->queue_lock, flags); | |
852ec809 BVA |
211 | } |
212 | EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue_nowait); | |
213 | ||
6a83e74d | 214 | /** |
9ef4d020 | 215 | * blk_mq_wait_quiesce_done() - wait until in-progress quiesce is done |
483239c7 | 216 | * @set: tag_set to wait on |
6a83e74d | 217 | * |
9ef4d020 | 218 | * Note: it is driver's responsibility for making sure that quiesce has |
483239c7 CH |
219 | * been started on or more of the request_queues of the tag_set. This |
220 | * function only waits for the quiesce on those request_queues that had | |
221 | * the quiesce flag set using blk_mq_quiesce_queue_nowait. | |
6a83e74d | 222 | */ |
483239c7 | 223 | void blk_mq_wait_quiesce_done(struct blk_mq_tag_set *set) |
6a83e74d | 224 | { |
483239c7 CH |
225 | if (set->flags & BLK_MQ_F_BLOCKING) |
226 | synchronize_srcu(set->srcu); | |
704b914f | 227 | else |
6a83e74d BVA |
228 | synchronize_rcu(); |
229 | } | |
9ef4d020 ML |
230 | EXPORT_SYMBOL_GPL(blk_mq_wait_quiesce_done); |
231 | ||
232 | /** | |
233 | * blk_mq_quiesce_queue() - wait until all ongoing dispatches have finished | |
234 | * @q: request queue. | |
235 | * | |
236 | * Note: this function does not prevent that the struct request end_io() | |
237 | * callback function is invoked. Once this function is returned, we make | |
238 | * sure no dispatch can happen until the queue is unquiesced via | |
239 | * blk_mq_unquiesce_queue(). | |
240 | */ | |
241 | void blk_mq_quiesce_queue(struct request_queue *q) | |
242 | { | |
243 | blk_mq_quiesce_queue_nowait(q); | |
8537380b CH |
244 | /* nothing to wait for non-mq queues */ |
245 | if (queue_is_mq(q)) | |
483239c7 | 246 | blk_mq_wait_quiesce_done(q->tag_set); |
9ef4d020 | 247 | } |
6a83e74d BVA |
248 | EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue); |
249 | ||
e4e73913 ML |
250 | /* |
251 | * blk_mq_unquiesce_queue() - counterpart of blk_mq_quiesce_queue() | |
252 | * @q: request queue. | |
253 | * | |
254 | * This function recovers queue into the state before quiescing | |
255 | * which is done by blk_mq_quiesce_queue. | |
256 | */ | |
257 | void blk_mq_unquiesce_queue(struct request_queue *q) | |
258 | { | |
e70feb8b ML |
259 | unsigned long flags; |
260 | bool run_queue = false; | |
261 | ||
262 | spin_lock_irqsave(&q->queue_lock, flags); | |
263 | if (WARN_ON_ONCE(q->quiesce_depth <= 0)) { | |
264 | ; | |
265 | } else if (!--q->quiesce_depth) { | |
266 | blk_queue_flag_clear(QUEUE_FLAG_QUIESCED, q); | |
267 | run_queue = true; | |
268 | } | |
269 | spin_unlock_irqrestore(&q->queue_lock, flags); | |
f4560ffe | 270 | |
1d9e9bc6 | 271 | /* dispatch requests which are inserted during quiescing */ |
e70feb8b ML |
272 | if (run_queue) |
273 | blk_mq_run_hw_queues(q, true); | |
e4e73913 ML |
274 | } |
275 | EXPORT_SYMBOL_GPL(blk_mq_unquiesce_queue); | |
276 | ||
414dd48e CL |
277 | void blk_mq_quiesce_tagset(struct blk_mq_tag_set *set) |
278 | { | |
279 | struct request_queue *q; | |
280 | ||
281 | mutex_lock(&set->tag_list_lock); | |
282 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
283 | if (!blk_queue_skip_tagset_quiesce(q)) | |
284 | blk_mq_quiesce_queue_nowait(q); | |
285 | } | |
286 | blk_mq_wait_quiesce_done(set); | |
287 | mutex_unlock(&set->tag_list_lock); | |
288 | } | |
289 | EXPORT_SYMBOL_GPL(blk_mq_quiesce_tagset); | |
290 | ||
291 | void blk_mq_unquiesce_tagset(struct blk_mq_tag_set *set) | |
292 | { | |
293 | struct request_queue *q; | |
294 | ||
295 | mutex_lock(&set->tag_list_lock); | |
296 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
297 | if (!blk_queue_skip_tagset_quiesce(q)) | |
298 | blk_mq_unquiesce_queue(q); | |
299 | } | |
300 | mutex_unlock(&set->tag_list_lock); | |
301 | } | |
302 | EXPORT_SYMBOL_GPL(blk_mq_unquiesce_tagset); | |
303 | ||
aed3ea94 JA |
304 | void blk_mq_wake_waiters(struct request_queue *q) |
305 | { | |
306 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 307 | unsigned long i; |
aed3ea94 JA |
308 | |
309 | queue_for_each_hw_ctx(q, hctx, i) | |
310 | if (blk_mq_hw_queue_mapped(hctx)) | |
311 | blk_mq_tag_wakeup_all(hctx->tags, true); | |
312 | } | |
313 | ||
52fdbbcc CH |
314 | void blk_rq_init(struct request_queue *q, struct request *rq) |
315 | { | |
316 | memset(rq, 0, sizeof(*rq)); | |
317 | ||
318 | INIT_LIST_HEAD(&rq->queuelist); | |
319 | rq->q = q; | |
320 | rq->__sector = (sector_t) -1; | |
321 | INIT_HLIST_NODE(&rq->hash); | |
322 | RB_CLEAR_NODE(&rq->rb_node); | |
323 | rq->tag = BLK_MQ_NO_TAG; | |
324 | rq->internal_tag = BLK_MQ_NO_TAG; | |
325 | rq->start_time_ns = ktime_get_ns(); | |
326 | rq->part = NULL; | |
327 | blk_crypto_rq_set_defaults(rq); | |
328 | } | |
329 | EXPORT_SYMBOL(blk_rq_init); | |
330 | ||
e4cdf1a1 | 331 | static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, |
fe6134f6 | 332 | struct blk_mq_tags *tags, unsigned int tag, u64 alloc_time_ns) |
320ae51f | 333 | { |
605f784e PB |
334 | struct blk_mq_ctx *ctx = data->ctx; |
335 | struct blk_mq_hw_ctx *hctx = data->hctx; | |
336 | struct request_queue *q = data->q; | |
e4cdf1a1 | 337 | struct request *rq = tags->static_rqs[tag]; |
c3a148d2 | 338 | |
c7b84d42 JA |
339 | rq->q = q; |
340 | rq->mq_ctx = ctx; | |
341 | rq->mq_hctx = hctx; | |
342 | rq->cmd_flags = data->cmd_flags; | |
343 | ||
344 | if (data->flags & BLK_MQ_REQ_PM) | |
345 | data->rq_flags |= RQF_PM; | |
346 | if (blk_queue_io_stat(q)) | |
347 | data->rq_flags |= RQF_IO_STAT; | |
348 | rq->rq_flags = data->rq_flags; | |
349 | ||
dd6216bb | 350 | if (data->rq_flags & RQF_SCHED_TAGS) { |
56f8da64 JA |
351 | rq->tag = BLK_MQ_NO_TAG; |
352 | rq->internal_tag = tag; | |
dd6216bb CH |
353 | } else { |
354 | rq->tag = tag; | |
355 | rq->internal_tag = BLK_MQ_NO_TAG; | |
e4cdf1a1 | 356 | } |
c7b84d42 | 357 | rq->timeout = 0; |
e4cdf1a1 | 358 | |
4f266f2b PB |
359 | if (blk_mq_need_time_stamp(rq)) |
360 | rq->start_time_ns = ktime_get_ns(); | |
361 | else | |
362 | rq->start_time_ns = 0; | |
af76e555 | 363 | rq->part = NULL; |
6f816b4b TH |
364 | #ifdef CONFIG_BLK_RQ_ALLOC_TIME |
365 | rq->alloc_time_ns = alloc_time_ns; | |
366 | #endif | |
544ccc8d | 367 | rq->io_start_time_ns = 0; |
3d244306 | 368 | rq->stats_sectors = 0; |
af76e555 CH |
369 | rq->nr_phys_segments = 0; |
370 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
371 | rq->nr_integrity_segments = 0; | |
372 | #endif | |
af76e555 CH |
373 | rq->end_io = NULL; |
374 | rq->end_io_data = NULL; | |
af76e555 | 375 | |
4f266f2b PB |
376 | blk_crypto_rq_set_defaults(rq); |
377 | INIT_LIST_HEAD(&rq->queuelist); | |
378 | /* tag was already set */ | |
379 | WRITE_ONCE(rq->deadline, 0); | |
0a467d0f | 380 | req_ref_set(rq, 1); |
7ea4d8a4 | 381 | |
dd6216bb | 382 | if (rq->rq_flags & RQF_USE_SCHED) { |
7ea4d8a4 CH |
383 | struct elevator_queue *e = data->q->elevator; |
384 | ||
4f266f2b PB |
385 | INIT_HLIST_NODE(&rq->hash); |
386 | RB_CLEAR_NODE(&rq->rb_node); | |
387 | ||
dd6216bb | 388 | if (e->type->ops.prepare_request) |
7ea4d8a4 | 389 | e->type->ops.prepare_request(rq); |
7ea4d8a4 CH |
390 | } |
391 | ||
e4cdf1a1 | 392 | return rq; |
5dee8577 CH |
393 | } |
394 | ||
349302da JA |
395 | static inline struct request * |
396 | __blk_mq_alloc_requests_batch(struct blk_mq_alloc_data *data, | |
397 | u64 alloc_time_ns) | |
398 | { | |
399 | unsigned int tag, tag_offset; | |
fe6134f6 | 400 | struct blk_mq_tags *tags; |
349302da | 401 | struct request *rq; |
fe6134f6 | 402 | unsigned long tag_mask; |
349302da JA |
403 | int i, nr = 0; |
404 | ||
fe6134f6 JA |
405 | tag_mask = blk_mq_get_tags(data, data->nr_tags, &tag_offset); |
406 | if (unlikely(!tag_mask)) | |
349302da JA |
407 | return NULL; |
408 | ||
fe6134f6 JA |
409 | tags = blk_mq_tags_from_data(data); |
410 | for (i = 0; tag_mask; i++) { | |
411 | if (!(tag_mask & (1UL << i))) | |
349302da JA |
412 | continue; |
413 | tag = tag_offset + i; | |
a22c00be | 414 | prefetch(tags->static_rqs[tag]); |
fe6134f6 JA |
415 | tag_mask &= ~(1UL << i); |
416 | rq = blk_mq_rq_ctx_init(data, tags, tag, alloc_time_ns); | |
013a7f95 | 417 | rq_list_add(data->cached_rq, rq); |
c5fc7b93 | 418 | nr++; |
349302da | 419 | } |
c5fc7b93 JA |
420 | /* caller already holds a reference, add for remainder */ |
421 | percpu_ref_get_many(&data->q->q_usage_counter, nr - 1); | |
349302da JA |
422 | data->nr_tags -= nr; |
423 | ||
013a7f95 | 424 | return rq_list_pop(data->cached_rq); |
349302da JA |
425 | } |
426 | ||
b90cfaed | 427 | static struct request *__blk_mq_alloc_requests(struct blk_mq_alloc_data *data) |
d2c0d383 | 428 | { |
e6e7abff | 429 | struct request_queue *q = data->q; |
6f816b4b | 430 | u64 alloc_time_ns = 0; |
47c122e3 | 431 | struct request *rq; |
600c3b0c | 432 | unsigned int tag; |
d2c0d383 | 433 | |
6f816b4b TH |
434 | /* alloc_time includes depth and tag waits */ |
435 | if (blk_queue_rq_alloc_time(q)) | |
436 | alloc_time_ns = ktime_get_ns(); | |
437 | ||
f9afca4d | 438 | if (data->cmd_flags & REQ_NOWAIT) |
03a07c92 | 439 | data->flags |= BLK_MQ_REQ_NOWAIT; |
d2c0d383 | 440 | |
781dd830 | 441 | if (q->elevator) { |
dd6216bb CH |
442 | /* |
443 | * All requests use scheduler tags when an I/O scheduler is | |
444 | * enabled for the queue. | |
445 | */ | |
446 | data->rq_flags |= RQF_SCHED_TAGS; | |
781dd830 | 447 | |
d2c0d383 | 448 | /* |
8d663f34 | 449 | * Flush/passthrough requests are special and go directly to the |
dd6216bb | 450 | * dispatch list. |
d2c0d383 | 451 | */ |
be4c4278 | 452 | if ((data->cmd_flags & REQ_OP_MASK) != REQ_OP_FLUSH && |
dd6216bb CH |
453 | !blk_op_is_passthrough(data->cmd_flags)) { |
454 | struct elevator_mq_ops *ops = &q->elevator->type->ops; | |
455 | ||
456 | WARN_ON_ONCE(data->flags & BLK_MQ_REQ_RESERVED); | |
457 | ||
458 | data->rq_flags |= RQF_USE_SCHED; | |
459 | if (ops->limit_depth) | |
460 | ops->limit_depth(data->cmd_flags, data); | |
461 | } | |
d2c0d383 CH |
462 | } |
463 | ||
bf0beec0 | 464 | retry: |
600c3b0c CH |
465 | data->ctx = blk_mq_get_ctx(q); |
466 | data->hctx = blk_mq_map_queue(q, data->cmd_flags, data->ctx); | |
dd6216bb | 467 | if (!(data->rq_flags & RQF_SCHED_TAGS)) |
600c3b0c CH |
468 | blk_mq_tag_busy(data->hctx); |
469 | ||
99e48cd6 JG |
470 | if (data->flags & BLK_MQ_REQ_RESERVED) |
471 | data->rq_flags |= RQF_RESV; | |
472 | ||
349302da JA |
473 | /* |
474 | * Try batched alloc if we want more than 1 tag. | |
475 | */ | |
476 | if (data->nr_tags > 1) { | |
477 | rq = __blk_mq_alloc_requests_batch(data, alloc_time_ns); | |
478 | if (rq) | |
479 | return rq; | |
480 | data->nr_tags = 1; | |
481 | } | |
482 | ||
bf0beec0 ML |
483 | /* |
484 | * Waiting allocations only fail because of an inactive hctx. In that | |
485 | * case just retry the hctx assignment and tag allocation as CPU hotplug | |
486 | * should have migrated us to an online CPU by now. | |
487 | */ | |
e4cdf1a1 | 488 | tag = blk_mq_get_tag(data); |
bf0beec0 ML |
489 | if (tag == BLK_MQ_NO_TAG) { |
490 | if (data->flags & BLK_MQ_REQ_NOWAIT) | |
491 | return NULL; | |
bf0beec0 | 492 | /* |
349302da JA |
493 | * Give up the CPU and sleep for a random short time to |
494 | * ensure that thread using a realtime scheduling class | |
495 | * are migrated off the CPU, and thus off the hctx that | |
496 | * is going away. | |
bf0beec0 ML |
497 | */ |
498 | msleep(3); | |
499 | goto retry; | |
500 | } | |
47c122e3 | 501 | |
fe6134f6 JA |
502 | return blk_mq_rq_ctx_init(data, blk_mq_tags_from_data(data), tag, |
503 | alloc_time_ns); | |
d2c0d383 CH |
504 | } |
505 | ||
4b6a5d9c JA |
506 | static struct request *blk_mq_rq_cache_fill(struct request_queue *q, |
507 | struct blk_plug *plug, | |
508 | blk_opf_t opf, | |
509 | blk_mq_req_flags_t flags) | |
320ae51f | 510 | { |
e6e7abff CH |
511 | struct blk_mq_alloc_data data = { |
512 | .q = q, | |
513 | .flags = flags, | |
16458cf3 | 514 | .cmd_flags = opf, |
4b6a5d9c JA |
515 | .nr_tags = plug->nr_ios, |
516 | .cached_rq = &plug->cached_rq, | |
e6e7abff | 517 | }; |
bd166ef1 | 518 | struct request *rq; |
320ae51f | 519 | |
4b6a5d9c JA |
520 | if (blk_queue_enter(q, flags)) |
521 | return NULL; | |
522 | ||
523 | plug->nr_ios = 1; | |
320ae51f | 524 | |
b90cfaed | 525 | rq = __blk_mq_alloc_requests(&data); |
4b6a5d9c JA |
526 | if (unlikely(!rq)) |
527 | blk_queue_exit(q); | |
528 | return rq; | |
529 | } | |
530 | ||
531 | static struct request *blk_mq_alloc_cached_request(struct request_queue *q, | |
532 | blk_opf_t opf, | |
533 | blk_mq_req_flags_t flags) | |
534 | { | |
535 | struct blk_plug *plug = current->plug; | |
536 | struct request *rq; | |
537 | ||
538 | if (!plug) | |
539 | return NULL; | |
40467282 | 540 | |
4b6a5d9c JA |
541 | if (rq_list_empty(plug->cached_rq)) { |
542 | if (plug->nr_ios == 1) | |
543 | return NULL; | |
544 | rq = blk_mq_rq_cache_fill(q, plug, opf, flags); | |
40467282 JC |
545 | if (!rq) |
546 | return NULL; | |
547 | } else { | |
548 | rq = rq_list_peek(&plug->cached_rq); | |
549 | if (!rq || rq->q != q) | |
550 | return NULL; | |
4b6a5d9c | 551 | |
40467282 JC |
552 | if (blk_mq_get_hctx_type(opf) != rq->mq_hctx->type) |
553 | return NULL; | |
554 | if (op_is_flush(rq->cmd_flags) != op_is_flush(opf)) | |
555 | return NULL; | |
556 | ||
557 | plug->cached_rq = rq_list_next(rq); | |
558 | } | |
4b6a5d9c | 559 | |
4b6a5d9c JA |
560 | rq->cmd_flags = opf; |
561 | INIT_LIST_HEAD(&rq->queuelist); | |
562 | return rq; | |
563 | } | |
564 | ||
565 | struct request *blk_mq_alloc_request(struct request_queue *q, blk_opf_t opf, | |
566 | blk_mq_req_flags_t flags) | |
567 | { | |
568 | struct request *rq; | |
569 | ||
570 | rq = blk_mq_alloc_cached_request(q, opf, flags); | |
571 | if (!rq) { | |
572 | struct blk_mq_alloc_data data = { | |
573 | .q = q, | |
574 | .flags = flags, | |
575 | .cmd_flags = opf, | |
576 | .nr_tags = 1, | |
577 | }; | |
578 | int ret; | |
579 | ||
580 | ret = blk_queue_enter(q, flags); | |
581 | if (ret) | |
582 | return ERR_PTR(ret); | |
583 | ||
584 | rq = __blk_mq_alloc_requests(&data); | |
585 | if (!rq) | |
586 | goto out_queue_exit; | |
587 | } | |
0c4de0f3 CH |
588 | rq->__data_len = 0; |
589 | rq->__sector = (sector_t) -1; | |
590 | rq->bio = rq->biotail = NULL; | |
320ae51f | 591 | return rq; |
a5ea5811 CH |
592 | out_queue_exit: |
593 | blk_queue_exit(q); | |
594 | return ERR_PTR(-EWOULDBLOCK); | |
320ae51f | 595 | } |
4bb659b1 | 596 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 597 | |
cd6ce148 | 598 | struct request *blk_mq_alloc_request_hctx(struct request_queue *q, |
16458cf3 | 599 | blk_opf_t opf, blk_mq_req_flags_t flags, unsigned int hctx_idx) |
1f5bd336 | 600 | { |
e6e7abff CH |
601 | struct blk_mq_alloc_data data = { |
602 | .q = q, | |
603 | .flags = flags, | |
16458cf3 | 604 | .cmd_flags = opf, |
47c122e3 | 605 | .nr_tags = 1, |
e6e7abff | 606 | }; |
600c3b0c | 607 | u64 alloc_time_ns = 0; |
e3c5a78c | 608 | struct request *rq; |
6d2809d5 | 609 | unsigned int cpu; |
600c3b0c | 610 | unsigned int tag; |
1f5bd336 ML |
611 | int ret; |
612 | ||
600c3b0c CH |
613 | /* alloc_time includes depth and tag waits */ |
614 | if (blk_queue_rq_alloc_time(q)) | |
615 | alloc_time_ns = ktime_get_ns(); | |
616 | ||
1f5bd336 ML |
617 | /* |
618 | * If the tag allocator sleeps we could get an allocation for a | |
619 | * different hardware context. No need to complicate the low level | |
620 | * allocator for this for the rare use case of a command tied to | |
621 | * a specific queue. | |
622 | */ | |
6ee858a3 KS |
623 | if (WARN_ON_ONCE(!(flags & BLK_MQ_REQ_NOWAIT)) || |
624 | WARN_ON_ONCE(!(flags & BLK_MQ_REQ_RESERVED))) | |
1f5bd336 ML |
625 | return ERR_PTR(-EINVAL); |
626 | ||
627 | if (hctx_idx >= q->nr_hw_queues) | |
628 | return ERR_PTR(-EIO); | |
629 | ||
3a0a5299 | 630 | ret = blk_queue_enter(q, flags); |
1f5bd336 ML |
631 | if (ret) |
632 | return ERR_PTR(ret); | |
633 | ||
c8712c6a CH |
634 | /* |
635 | * Check if the hardware context is actually mapped to anything. | |
636 | * If not tell the caller that it should skip this queue. | |
637 | */ | |
a5ea5811 | 638 | ret = -EXDEV; |
4e5cc99e | 639 | data.hctx = xa_load(&q->hctx_table, hctx_idx); |
e6e7abff | 640 | if (!blk_mq_hw_queue_mapped(data.hctx)) |
a5ea5811 | 641 | goto out_queue_exit; |
e6e7abff | 642 | cpu = cpumask_first_and(data.hctx->cpumask, cpu_online_mask); |
14dc7a18 BVA |
643 | if (cpu >= nr_cpu_ids) |
644 | goto out_queue_exit; | |
e6e7abff | 645 | data.ctx = __blk_mq_get_ctx(q, cpu); |
1f5bd336 | 646 | |
dd6216bb CH |
647 | if (q->elevator) |
648 | data.rq_flags |= RQF_SCHED_TAGS; | |
781dd830 | 649 | else |
dd6216bb | 650 | blk_mq_tag_busy(data.hctx); |
600c3b0c | 651 | |
99e48cd6 JG |
652 | if (flags & BLK_MQ_REQ_RESERVED) |
653 | data.rq_flags |= RQF_RESV; | |
654 | ||
a5ea5811 | 655 | ret = -EWOULDBLOCK; |
600c3b0c CH |
656 | tag = blk_mq_get_tag(&data); |
657 | if (tag == BLK_MQ_NO_TAG) | |
a5ea5811 | 658 | goto out_queue_exit; |
e3c5a78c | 659 | rq = blk_mq_rq_ctx_init(&data, blk_mq_tags_from_data(&data), tag, |
fe6134f6 | 660 | alloc_time_ns); |
e3c5a78c JG |
661 | rq->__data_len = 0; |
662 | rq->__sector = (sector_t) -1; | |
663 | rq->bio = rq->biotail = NULL; | |
664 | return rq; | |
600c3b0c | 665 | |
a5ea5811 CH |
666 | out_queue_exit: |
667 | blk_queue_exit(q); | |
668 | return ERR_PTR(ret); | |
1f5bd336 ML |
669 | } |
670 | EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx); | |
671 | ||
12f5b931 KB |
672 | static void __blk_mq_free_request(struct request *rq) |
673 | { | |
674 | struct request_queue *q = rq->q; | |
675 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
ea4f995e | 676 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
12f5b931 KB |
677 | const int sched_tag = rq->internal_tag; |
678 | ||
a892c8d5 | 679 | blk_crypto_free_request(rq); |
986d413b | 680 | blk_pm_mark_last_busy(rq); |
ea4f995e | 681 | rq->mq_hctx = NULL; |
ddad5933 TL |
682 | |
683 | if (rq->rq_flags & RQF_MQ_INFLIGHT) | |
684 | __blk_mq_dec_active_requests(hctx); | |
685 | ||
76647368 | 686 | if (rq->tag != BLK_MQ_NO_TAG) |
cae740a0 | 687 | blk_mq_put_tag(hctx->tags, ctx, rq->tag); |
76647368 | 688 | if (sched_tag != BLK_MQ_NO_TAG) |
cae740a0 | 689 | blk_mq_put_tag(hctx->sched_tags, ctx, sched_tag); |
12f5b931 KB |
690 | blk_mq_sched_restart(hctx); |
691 | blk_queue_exit(q); | |
692 | } | |
693 | ||
6af54051 | 694 | void blk_mq_free_request(struct request *rq) |
320ae51f | 695 | { |
320ae51f | 696 | struct request_queue *q = rq->q; |
6af54051 | 697 | |
dd6216bb | 698 | if ((rq->rq_flags & RQF_USE_SCHED) && |
222ee581 CH |
699 | q->elevator->type->ops.finish_request) |
700 | q->elevator->type->ops.finish_request(rq); | |
320ae51f | 701 | |
7beb2f84 | 702 | if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq))) |
d152c682 | 703 | laptop_io_completion(q->disk->bdi); |
7beb2f84 | 704 | |
a7905043 | 705 | rq_qos_done(q, rq); |
0d2602ca | 706 | |
12f5b931 | 707 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); |
0a467d0f | 708 | if (req_ref_put_and_test(rq)) |
12f5b931 | 709 | __blk_mq_free_request(rq); |
320ae51f | 710 | } |
1a3b595a | 711 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 712 | |
47c122e3 | 713 | void blk_mq_free_plug_rqs(struct blk_plug *plug) |
320ae51f | 714 | { |
013a7f95 | 715 | struct request *rq; |
fe1f4526 | 716 | |
c5fc7b93 | 717 | while ((rq = rq_list_pop(&plug->cached_rq)) != NULL) |
47c122e3 | 718 | blk_mq_free_request(rq); |
47c122e3 | 719 | } |
522a7775 | 720 | |
22350ad7 CH |
721 | void blk_dump_rq_flags(struct request *rq, char *msg) |
722 | { | |
723 | printk(KERN_INFO "%s: dev %s: flags=%llx\n", msg, | |
f3fa33ac | 724 | rq->q->disk ? rq->q->disk->disk_name : "?", |
16458cf3 | 725 | (__force unsigned long long) rq->cmd_flags); |
22350ad7 CH |
726 | |
727 | printk(KERN_INFO " sector %llu, nr/cnr %u/%u\n", | |
728 | (unsigned long long)blk_rq_pos(rq), | |
729 | blk_rq_sectors(rq), blk_rq_cur_sectors(rq)); | |
730 | printk(KERN_INFO " bio %p, biotail %p, len %u\n", | |
731 | rq->bio, rq->biotail, blk_rq_bytes(rq)); | |
732 | } | |
733 | EXPORT_SYMBOL(blk_dump_rq_flags); | |
734 | ||
9be3e06f JA |
735 | static void req_bio_endio(struct request *rq, struct bio *bio, |
736 | unsigned int nbytes, blk_status_t error) | |
737 | { | |
478eb72b | 738 | if (unlikely(error)) { |
9be3e06f | 739 | bio->bi_status = error; |
478eb72b | 740 | } else if (req_op(rq) == REQ_OP_ZONE_APPEND) { |
9be3e06f JA |
741 | /* |
742 | * Partial zone append completions cannot be supported as the | |
743 | * BIO fragments may end up not being written sequentially. | |
744 | */ | |
297db731 | 745 | if (bio->bi_iter.bi_size != nbytes) |
9be3e06f JA |
746 | bio->bi_status = BLK_STS_IOERR; |
747 | else | |
748 | bio->bi_iter.bi_sector = rq->__sector; | |
749 | } | |
750 | ||
478eb72b PB |
751 | bio_advance(bio, nbytes); |
752 | ||
753 | if (unlikely(rq->rq_flags & RQF_QUIET)) | |
754 | bio_set_flag(bio, BIO_QUIET); | |
9be3e06f JA |
755 | /* don't actually finish bio if it's part of flush sequence */ |
756 | if (bio->bi_iter.bi_size == 0 && !(rq->rq_flags & RQF_FLUSH_SEQ)) | |
757 | bio_endio(bio); | |
758 | } | |
759 | ||
760 | static void blk_account_io_completion(struct request *req, unsigned int bytes) | |
761 | { | |
762 | if (req->part && blk_do_io_stat(req)) { | |
763 | const int sgrp = op_stat_group(req_op(req)); | |
764 | ||
765 | part_stat_lock(); | |
766 | part_stat_add(req->part, sectors[sgrp], bytes >> 9); | |
767 | part_stat_unlock(); | |
768 | } | |
769 | } | |
770 | ||
0d7a29a2 CH |
771 | static void blk_print_req_error(struct request *req, blk_status_t status) |
772 | { | |
773 | printk_ratelimited(KERN_ERR | |
774 | "%s error, dev %s, sector %llu op 0x%x:(%s) flags 0x%x " | |
775 | "phys_seg %u prio class %u\n", | |
776 | blk_status_to_str(status), | |
f3fa33ac | 777 | req->q->disk ? req->q->disk->disk_name : "?", |
16458cf3 BVA |
778 | blk_rq_pos(req), (__force u32)req_op(req), |
779 | blk_op_str(req_op(req)), | |
780 | (__force u32)(req->cmd_flags & ~REQ_OP_MASK), | |
0d7a29a2 CH |
781 | req->nr_phys_segments, |
782 | IOPRIO_PRIO_CLASS(req->ioprio)); | |
783 | } | |
784 | ||
5581a5dd JA |
785 | /* |
786 | * Fully end IO on a request. Does not support partial completions, or | |
787 | * errors. | |
788 | */ | |
789 | static void blk_complete_request(struct request *req) | |
790 | { | |
791 | const bool is_flush = (req->rq_flags & RQF_FLUSH_SEQ) != 0; | |
792 | int total_bytes = blk_rq_bytes(req); | |
793 | struct bio *bio = req->bio; | |
794 | ||
795 | trace_block_rq_complete(req, BLK_STS_OK, total_bytes); | |
796 | ||
797 | if (!bio) | |
798 | return; | |
799 | ||
800 | #ifdef CONFIG_BLK_DEV_INTEGRITY | |
801 | if (blk_integrity_rq(req) && req_op(req) == REQ_OP_READ) | |
802 | req->q->integrity.profile->complete_fn(req, total_bytes); | |
803 | #endif | |
804 | ||
9cd1e566 EB |
805 | /* |
806 | * Upper layers may call blk_crypto_evict_key() anytime after the last | |
807 | * bio_endio(). Therefore, the keyslot must be released before that. | |
808 | */ | |
809 | blk_crypto_rq_put_keyslot(req); | |
810 | ||
5581a5dd JA |
811 | blk_account_io_completion(req, total_bytes); |
812 | ||
813 | do { | |
814 | struct bio *next = bio->bi_next; | |
815 | ||
816 | /* Completion has already been traced */ | |
817 | bio_clear_flag(bio, BIO_TRACE_COMPLETION); | |
a12821d5 PR |
818 | |
819 | if (req_op(req) == REQ_OP_ZONE_APPEND) | |
820 | bio->bi_iter.bi_sector = req->__sector; | |
821 | ||
5581a5dd JA |
822 | if (!is_flush) |
823 | bio_endio(bio); | |
824 | bio = next; | |
825 | } while (bio); | |
826 | ||
827 | /* | |
828 | * Reset counters so that the request stacking driver | |
829 | * can find how many bytes remain in the request | |
830 | * later. | |
831 | */ | |
ab3e1d3b JA |
832 | if (!req->end_io) { |
833 | req->bio = NULL; | |
834 | req->__data_len = 0; | |
835 | } | |
5581a5dd JA |
836 | } |
837 | ||
9be3e06f JA |
838 | /** |
839 | * blk_update_request - Complete multiple bytes without completing the request | |
840 | * @req: the request being processed | |
841 | * @error: block status code | |
842 | * @nr_bytes: number of bytes to complete for @req | |
843 | * | |
844 | * Description: | |
845 | * Ends I/O on a number of bytes attached to @req, but doesn't complete | |
846 | * the request structure even if @req doesn't have leftover. | |
847 | * If @req has leftover, sets it up for the next range of segments. | |
848 | * | |
849 | * Passing the result of blk_rq_bytes() as @nr_bytes guarantees | |
850 | * %false return from this function. | |
851 | * | |
852 | * Note: | |
853 | * The RQF_SPECIAL_PAYLOAD flag is ignored on purpose in this function | |
854 | * except in the consistency check at the end of this function. | |
855 | * | |
856 | * Return: | |
857 | * %false - this request doesn't have any more data | |
858 | * %true - this request has more data | |
859 | **/ | |
860 | bool blk_update_request(struct request *req, blk_status_t error, | |
861 | unsigned int nr_bytes) | |
862 | { | |
863 | int total_bytes; | |
864 | ||
8a7d267b | 865 | trace_block_rq_complete(req, error, nr_bytes); |
9be3e06f JA |
866 | |
867 | if (!req->bio) | |
868 | return false; | |
869 | ||
870 | #ifdef CONFIG_BLK_DEV_INTEGRITY | |
871 | if (blk_integrity_rq(req) && req_op(req) == REQ_OP_READ && | |
872 | error == BLK_STS_OK) | |
873 | req->q->integrity.profile->complete_fn(req, nr_bytes); | |
874 | #endif | |
875 | ||
9cd1e566 EB |
876 | /* |
877 | * Upper layers may call blk_crypto_evict_key() anytime after the last | |
878 | * bio_endio(). Therefore, the keyslot must be released before that. | |
879 | */ | |
880 | if (blk_crypto_rq_has_keyslot(req) && nr_bytes >= blk_rq_bytes(req)) | |
881 | __blk_crypto_rq_put_keyslot(req); | |
882 | ||
9be3e06f | 883 | if (unlikely(error && !blk_rq_is_passthrough(req) && |
3d973a76 CH |
884 | !(req->rq_flags & RQF_QUIET)) && |
885 | !test_bit(GD_DEAD, &req->q->disk->state)) { | |
9be3e06f | 886 | blk_print_req_error(req, error); |
d5869fdc YS |
887 | trace_block_rq_error(req, error, nr_bytes); |
888 | } | |
9be3e06f JA |
889 | |
890 | blk_account_io_completion(req, nr_bytes); | |
891 | ||
892 | total_bytes = 0; | |
893 | while (req->bio) { | |
894 | struct bio *bio = req->bio; | |
895 | unsigned bio_bytes = min(bio->bi_iter.bi_size, nr_bytes); | |
896 | ||
897 | if (bio_bytes == bio->bi_iter.bi_size) | |
898 | req->bio = bio->bi_next; | |
899 | ||
900 | /* Completion has already been traced */ | |
901 | bio_clear_flag(bio, BIO_TRACE_COMPLETION); | |
902 | req_bio_endio(req, bio, bio_bytes, error); | |
903 | ||
904 | total_bytes += bio_bytes; | |
905 | nr_bytes -= bio_bytes; | |
906 | ||
907 | if (!nr_bytes) | |
908 | break; | |
909 | } | |
910 | ||
911 | /* | |
912 | * completely done | |
913 | */ | |
914 | if (!req->bio) { | |
915 | /* | |
916 | * Reset counters so that the request stacking driver | |
917 | * can find how many bytes remain in the request | |
918 | * later. | |
919 | */ | |
920 | req->__data_len = 0; | |
921 | return false; | |
922 | } | |
923 | ||
924 | req->__data_len -= total_bytes; | |
925 | ||
926 | /* update sector only for requests with clear definition of sector */ | |
927 | if (!blk_rq_is_passthrough(req)) | |
928 | req->__sector += total_bytes >> 9; | |
929 | ||
930 | /* mixed attributes always follow the first bio */ | |
931 | if (req->rq_flags & RQF_MIXED_MERGE) { | |
932 | req->cmd_flags &= ~REQ_FAILFAST_MASK; | |
933 | req->cmd_flags |= req->bio->bi_opf & REQ_FAILFAST_MASK; | |
934 | } | |
935 | ||
936 | if (!(req->rq_flags & RQF_SPECIAL_PAYLOAD)) { | |
937 | /* | |
938 | * If total number of sectors is less than the first segment | |
939 | * size, something has gone terribly wrong. | |
940 | */ | |
941 | if (blk_rq_bytes(req) < blk_rq_cur_bytes(req)) { | |
942 | blk_dump_rq_flags(req, "request botched"); | |
943 | req->__data_len = blk_rq_cur_bytes(req); | |
944 | } | |
945 | ||
946 | /* recalculate the number of segments */ | |
947 | req->nr_phys_segments = blk_recalc_rq_segments(req); | |
948 | } | |
949 | ||
950 | return true; | |
951 | } | |
952 | EXPORT_SYMBOL_GPL(blk_update_request); | |
953 | ||
450b7879 CH |
954 | static inline void blk_account_io_done(struct request *req, u64 now) |
955 | { | |
5a80bd07 HC |
956 | trace_block_io_done(req); |
957 | ||
450b7879 CH |
958 | /* |
959 | * Account IO completion. flush_rq isn't accounted as a | |
960 | * normal IO on queueing nor completion. Accounting the | |
961 | * containing request is enough. | |
962 | */ | |
963 | if (blk_do_io_stat(req) && req->part && | |
06965037 CK |
964 | !(req->rq_flags & RQF_FLUSH_SEQ)) { |
965 | const int sgrp = op_stat_group(req_op(req)); | |
450b7879 | 966 | |
06965037 CK |
967 | part_stat_lock(); |
968 | update_io_ticks(req->part, jiffies, true); | |
969 | part_stat_inc(req->part, ios[sgrp]); | |
970 | part_stat_add(req->part, nsecs[sgrp], now - req->start_time_ns); | |
971 | part_stat_unlock(); | |
972 | } | |
450b7879 CH |
973 | } |
974 | ||
975 | static inline void blk_account_io_start(struct request *req) | |
976 | { | |
5a80bd07 HC |
977 | trace_block_io_start(req); |
978 | ||
e165fb4d CK |
979 | if (blk_do_io_stat(req)) { |
980 | /* | |
981 | * All non-passthrough requests are created from a bio with one | |
982 | * exception: when a flush command that is part of a flush sequence | |
983 | * generated by the state machine in blk-flush.c is cloned onto the | |
984 | * lower device by dm-multipath we can get here without a bio. | |
985 | */ | |
986 | if (req->bio) | |
987 | req->part = req->bio->bi_bdev; | |
988 | else | |
989 | req->part = req->q->disk->part0; | |
990 | ||
991 | part_stat_lock(); | |
992 | update_io_ticks(req->part, jiffies, false); | |
993 | part_stat_unlock(); | |
994 | } | |
450b7879 CH |
995 | } |
996 | ||
f794f335 | 997 | static inline void __blk_mq_end_request_acct(struct request *rq, u64 now) |
320ae51f | 998 | { |
54bdd67d | 999 | if (rq->rq_flags & RQF_STATS) |
522a7775 | 1000 | blk_stat_add(rq, now); |
4bc6339a | 1001 | |
87890092 | 1002 | blk_mq_sched_completed_request(rq, now); |
522a7775 | 1003 | blk_account_io_done(rq, now); |
f794f335 | 1004 | } |
522a7775 | 1005 | |
f794f335 JA |
1006 | inline void __blk_mq_end_request(struct request *rq, blk_status_t error) |
1007 | { | |
1008 | if (blk_mq_need_time_stamp(rq)) | |
1009 | __blk_mq_end_request_acct(rq, ktime_get_ns()); | |
0d11e6ac | 1010 | |
91b63639 | 1011 | if (rq->end_io) { |
a7905043 | 1012 | rq_qos_done(rq->q, rq); |
de671d61 JA |
1013 | if (rq->end_io(rq, error) == RQ_END_IO_FREE) |
1014 | blk_mq_free_request(rq); | |
91b63639 | 1015 | } else { |
320ae51f | 1016 | blk_mq_free_request(rq); |
91b63639 | 1017 | } |
320ae51f | 1018 | } |
c8a446ad | 1019 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 1020 | |
2a842aca | 1021 | void blk_mq_end_request(struct request *rq, blk_status_t error) |
63151a44 CH |
1022 | { |
1023 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
1024 | BUG(); | |
c8a446ad | 1025 | __blk_mq_end_request(rq, error); |
63151a44 | 1026 | } |
c8a446ad | 1027 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 1028 | |
f794f335 JA |
1029 | #define TAG_COMP_BATCH 32 |
1030 | ||
1031 | static inline void blk_mq_flush_tag_batch(struct blk_mq_hw_ctx *hctx, | |
1032 | int *tag_array, int nr_tags) | |
1033 | { | |
1034 | struct request_queue *q = hctx->queue; | |
1035 | ||
3b87c6ea ML |
1036 | /* |
1037 | * All requests should have been marked as RQF_MQ_INFLIGHT, so | |
1038 | * update hctx->nr_active in batch | |
1039 | */ | |
1040 | if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) | |
1041 | __blk_mq_sub_active_requests(hctx, nr_tags); | |
1042 | ||
f794f335 JA |
1043 | blk_mq_put_tags(hctx->tags, tag_array, nr_tags); |
1044 | percpu_ref_put_many(&q->q_usage_counter, nr_tags); | |
1045 | } | |
1046 | ||
1047 | void blk_mq_end_request_batch(struct io_comp_batch *iob) | |
1048 | { | |
1049 | int tags[TAG_COMP_BATCH], nr_tags = 0; | |
02f7eab0 | 1050 | struct blk_mq_hw_ctx *cur_hctx = NULL; |
f794f335 JA |
1051 | struct request *rq; |
1052 | u64 now = 0; | |
1053 | ||
1054 | if (iob->need_ts) | |
1055 | now = ktime_get_ns(); | |
1056 | ||
1057 | while ((rq = rq_list_pop(&iob->req_list)) != NULL) { | |
1058 | prefetch(rq->bio); | |
1059 | prefetch(rq->rq_next); | |
1060 | ||
5581a5dd | 1061 | blk_complete_request(rq); |
f794f335 JA |
1062 | if (iob->need_ts) |
1063 | __blk_mq_end_request_acct(rq, now); | |
1064 | ||
98b26a0e JA |
1065 | rq_qos_done(rq->q, rq); |
1066 | ||
ab3e1d3b JA |
1067 | /* |
1068 | * If end_io handler returns NONE, then it still has | |
1069 | * ownership of the request. | |
1070 | */ | |
1071 | if (rq->end_io && rq->end_io(rq, 0) == RQ_END_IO_NONE) | |
1072 | continue; | |
1073 | ||
f794f335 | 1074 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); |
0a467d0f | 1075 | if (!req_ref_put_and_test(rq)) |
f794f335 JA |
1076 | continue; |
1077 | ||
1078 | blk_crypto_free_request(rq); | |
1079 | blk_pm_mark_last_busy(rq); | |
f794f335 | 1080 | |
02f7eab0 JA |
1081 | if (nr_tags == TAG_COMP_BATCH || cur_hctx != rq->mq_hctx) { |
1082 | if (cur_hctx) | |
1083 | blk_mq_flush_tag_batch(cur_hctx, tags, nr_tags); | |
f794f335 | 1084 | nr_tags = 0; |
02f7eab0 | 1085 | cur_hctx = rq->mq_hctx; |
f794f335 JA |
1086 | } |
1087 | tags[nr_tags++] = rq->tag; | |
f794f335 JA |
1088 | } |
1089 | ||
1090 | if (nr_tags) | |
02f7eab0 | 1091 | blk_mq_flush_tag_batch(cur_hctx, tags, nr_tags); |
f794f335 JA |
1092 | } |
1093 | EXPORT_SYMBOL_GPL(blk_mq_end_request_batch); | |
1094 | ||
f9ab4918 | 1095 | static void blk_complete_reqs(struct llist_head *list) |
320ae51f | 1096 | { |
f9ab4918 SAS |
1097 | struct llist_node *entry = llist_reverse_order(llist_del_all(list)); |
1098 | struct request *rq, *next; | |
c3077b5d | 1099 | |
f9ab4918 | 1100 | llist_for_each_entry_safe(rq, next, entry, ipi_list) |
c3077b5d | 1101 | rq->q->mq_ops->complete(rq); |
320ae51f | 1102 | } |
320ae51f | 1103 | |
f9ab4918 | 1104 | static __latent_entropy void blk_done_softirq(struct softirq_action *h) |
320ae51f | 1105 | { |
f9ab4918 | 1106 | blk_complete_reqs(this_cpu_ptr(&blk_cpu_done)); |
115243f5 CH |
1107 | } |
1108 | ||
c3077b5d CH |
1109 | static int blk_softirq_cpu_dead(unsigned int cpu) |
1110 | { | |
f9ab4918 | 1111 | blk_complete_reqs(&per_cpu(blk_cpu_done, cpu)); |
c3077b5d CH |
1112 | return 0; |
1113 | } | |
1114 | ||
40d09b53 | 1115 | static void __blk_mq_complete_request_remote(void *data) |
c3077b5d | 1116 | { |
f9ab4918 | 1117 | __raise_softirq_irqoff(BLOCK_SOFTIRQ); |
c3077b5d CH |
1118 | } |
1119 | ||
96339526 CH |
1120 | static inline bool blk_mq_complete_need_ipi(struct request *rq) |
1121 | { | |
1122 | int cpu = raw_smp_processor_id(); | |
1123 | ||
1124 | if (!IS_ENABLED(CONFIG_SMP) || | |
1125 | !test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) | |
1126 | return false; | |
71425189 SAS |
1127 | /* |
1128 | * With force threaded interrupts enabled, raising softirq from an SMP | |
1129 | * function call will always result in waking the ksoftirqd thread. | |
1130 | * This is probably worse than completing the request on a different | |
1131 | * cache domain. | |
1132 | */ | |
91cc470e | 1133 | if (force_irqthreads()) |
71425189 | 1134 | return false; |
96339526 CH |
1135 | |
1136 | /* same CPU or cache domain? Complete locally */ | |
1137 | if (cpu == rq->mq_ctx->cpu || | |
1138 | (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags) && | |
1139 | cpus_share_cache(cpu, rq->mq_ctx->cpu))) | |
1140 | return false; | |
1141 | ||
1142 | /* don't try to IPI to an offline CPU */ | |
1143 | return cpu_online(rq->mq_ctx->cpu); | |
1144 | } | |
1145 | ||
f9ab4918 SAS |
1146 | static void blk_mq_complete_send_ipi(struct request *rq) |
1147 | { | |
1148 | struct llist_head *list; | |
1149 | unsigned int cpu; | |
1150 | ||
1151 | cpu = rq->mq_ctx->cpu; | |
1152 | list = &per_cpu(blk_cpu_done, cpu); | |
1153 | if (llist_add(&rq->ipi_list, list)) { | |
1154 | INIT_CSD(&rq->csd, __blk_mq_complete_request_remote, rq); | |
1155 | smp_call_function_single_async(cpu, &rq->csd); | |
1156 | } | |
1157 | } | |
1158 | ||
1159 | static void blk_mq_raise_softirq(struct request *rq) | |
1160 | { | |
1161 | struct llist_head *list; | |
1162 | ||
1163 | preempt_disable(); | |
1164 | list = this_cpu_ptr(&blk_cpu_done); | |
1165 | if (llist_add(&rq->ipi_list, list)) | |
1166 | raise_softirq(BLOCK_SOFTIRQ); | |
1167 | preempt_enable(); | |
1168 | } | |
1169 | ||
40d09b53 | 1170 | bool blk_mq_complete_request_remote(struct request *rq) |
320ae51f | 1171 | { |
af78ff7c | 1172 | WRITE_ONCE(rq->state, MQ_RQ_COMPLETE); |
36e76539 | 1173 | |
4ab32bf3 | 1174 | /* |
f168420c LS |
1175 | * For request which hctx has only one ctx mapping, |
1176 | * or a polled request, always complete locally, | |
1177 | * it's pointless to redirect the completion. | |
4ab32bf3 | 1178 | */ |
30654614 ET |
1179 | if ((rq->mq_hctx->nr_ctx == 1 && |
1180 | rq->mq_ctx->cpu == raw_smp_processor_id()) || | |
1181 | rq->cmd_flags & REQ_POLLED) | |
40d09b53 | 1182 | return false; |
38535201 | 1183 | |
96339526 | 1184 | if (blk_mq_complete_need_ipi(rq)) { |
f9ab4918 SAS |
1185 | blk_mq_complete_send_ipi(rq); |
1186 | return true; | |
3d6efbf6 | 1187 | } |
40d09b53 | 1188 | |
f9ab4918 SAS |
1189 | if (rq->q->nr_hw_queues == 1) { |
1190 | blk_mq_raise_softirq(rq); | |
1191 | return true; | |
1192 | } | |
1193 | return false; | |
40d09b53 CH |
1194 | } |
1195 | EXPORT_SYMBOL_GPL(blk_mq_complete_request_remote); | |
1196 | ||
1197 | /** | |
1198 | * blk_mq_complete_request - end I/O on a request | |
1199 | * @rq: the request being processed | |
1200 | * | |
1201 | * Description: | |
1202 | * Complete a request by scheduling the ->complete_rq operation. | |
1203 | **/ | |
1204 | void blk_mq_complete_request(struct request *rq) | |
1205 | { | |
1206 | if (!blk_mq_complete_request_remote(rq)) | |
1207 | rq->q->mq_ops->complete(rq); | |
320ae51f | 1208 | } |
15f73f5b | 1209 | EXPORT_SYMBOL(blk_mq_complete_request); |
30a91cb4 | 1210 | |
105663f7 AA |
1211 | /** |
1212 | * blk_mq_start_request - Start processing a request | |
1213 | * @rq: Pointer to request to be started | |
1214 | * | |
1215 | * Function used by device drivers to notify the block layer that a request | |
1216 | * is going to be processed now, so blk layer can do proper initializations | |
1217 | * such as starting the timeout timer. | |
1218 | */ | |
e2490073 | 1219 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
1220 | { |
1221 | struct request_queue *q = rq->q; | |
1222 | ||
a54895fa | 1223 | trace_block_rq_issue(rq); |
320ae51f | 1224 | |
cf43e6be | 1225 | if (test_bit(QUEUE_FLAG_STATS, &q->queue_flags)) { |
4cddeaca | 1226 | rq->io_start_time_ns = ktime_get_ns(); |
3d244306 | 1227 | rq->stats_sectors = blk_rq_sectors(rq); |
cf43e6be | 1228 | rq->rq_flags |= RQF_STATS; |
a7905043 | 1229 | rq_qos_issue(q, rq); |
cf43e6be JA |
1230 | } |
1231 | ||
1d9bd516 | 1232 | WARN_ON_ONCE(blk_mq_rq_state(rq) != MQ_RQ_IDLE); |
538b7534 | 1233 | |
1d9bd516 | 1234 | blk_add_timer(rq); |
12f5b931 | 1235 | WRITE_ONCE(rq->state, MQ_RQ_IN_FLIGHT); |
49f5baa5 | 1236 | |
54d4e6ab MG |
1237 | #ifdef CONFIG_BLK_DEV_INTEGRITY |
1238 | if (blk_integrity_rq(rq) && req_op(rq) == REQ_OP_WRITE) | |
1239 | q->integrity.profile->prepare_fn(rq); | |
1240 | #endif | |
3e08773c | 1241 | if (rq->bio && rq->bio->bi_opf & REQ_POLLED) |
f6c80cff | 1242 | WRITE_ONCE(rq->bio->bi_cookie, rq->mq_hctx->queue_num); |
320ae51f | 1243 | } |
e2490073 | 1244 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 1245 | |
a327c341 ML |
1246 | /* |
1247 | * Allow 2x BLK_MAX_REQUEST_COUNT requests on plug queue for multiple | |
1248 | * queues. This is important for md arrays to benefit from merging | |
1249 | * requests. | |
1250 | */ | |
1251 | static inline unsigned short blk_plug_max_rq_count(struct blk_plug *plug) | |
1252 | { | |
1253 | if (plug->multiple_queues) | |
1254 | return BLK_MAX_REQUEST_COUNT * 2; | |
1255 | return BLK_MAX_REQUEST_COUNT; | |
1256 | } | |
1257 | ||
1258 | static void blk_add_rq_to_plug(struct blk_plug *plug, struct request *rq) | |
1259 | { | |
1260 | struct request *last = rq_list_peek(&plug->mq_list); | |
1261 | ||
1262 | if (!plug->rq_count) { | |
1263 | trace_block_plug(rq->q); | |
1264 | } else if (plug->rq_count >= blk_plug_max_rq_count(plug) || | |
1265 | (!blk_queue_nomerges(rq->q) && | |
1266 | blk_rq_bytes(last) >= BLK_PLUG_FLUSH_SIZE)) { | |
1267 | blk_mq_flush_plug_list(plug, false); | |
878eb6e4 | 1268 | last = NULL; |
a327c341 ML |
1269 | trace_block_plug(rq->q); |
1270 | } | |
1271 | ||
1272 | if (!plug->multiple_queues && last && last->q != rq->q) | |
1273 | plug->multiple_queues = true; | |
c6b7a3a2 ML |
1274 | /* |
1275 | * Any request allocated from sched tags can't be issued to | |
1276 | * ->queue_rqs() directly | |
1277 | */ | |
1278 | if (!plug->has_elevator && (rq->rq_flags & RQF_SCHED_TAGS)) | |
a327c341 ML |
1279 | plug->has_elevator = true; |
1280 | rq->rq_next = NULL; | |
1281 | rq_list_add(&plug->mq_list, rq); | |
1282 | plug->rq_count++; | |
1283 | } | |
1284 | ||
4054cff9 CH |
1285 | /** |
1286 | * blk_execute_rq_nowait - insert a request to I/O scheduler for execution | |
4054cff9 CH |
1287 | * @rq: request to insert |
1288 | * @at_head: insert request at head or tail of queue | |
4054cff9 CH |
1289 | * |
1290 | * Description: | |
1291 | * Insert a fully prepared request at the back of the I/O scheduler queue | |
1292 | * for execution. Don't wait for completion. | |
1293 | * | |
1294 | * Note: | |
1295 | * This function will invoke @done directly if the queue is dead. | |
1296 | */ | |
e2e53086 | 1297 | void blk_execute_rq_nowait(struct request *rq, bool at_head) |
4054cff9 | 1298 | { |
f0dbe6e8 CH |
1299 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
1300 | ||
ae948fd6 CH |
1301 | WARN_ON(irqs_disabled()); |
1302 | WARN_ON(!blk_rq_is_passthrough(rq)); | |
4054cff9 | 1303 | |
ae948fd6 | 1304 | blk_account_io_start(rq); |
110fdb44 PR |
1305 | |
1306 | /* | |
1307 | * As plugging can be enabled for passthrough requests on a zoned | |
1308 | * device, directly accessing the plug instead of using blk_mq_plug() | |
1309 | * should not have any consequences. | |
1310 | */ | |
f0dbe6e8 | 1311 | if (current->plug && !at_head) { |
ae948fd6 | 1312 | blk_add_rq_to_plug(current->plug, rq); |
f0dbe6e8 CH |
1313 | return; |
1314 | } | |
1315 | ||
710fa378 | 1316 | blk_mq_insert_request(rq, at_head ? BLK_MQ_INSERT_AT_HEAD : 0); |
f0dbe6e8 | 1317 | blk_mq_run_hw_queue(hctx, false); |
4054cff9 CH |
1318 | } |
1319 | EXPORT_SYMBOL_GPL(blk_execute_rq_nowait); | |
1320 | ||
32ac5a9b CH |
1321 | struct blk_rq_wait { |
1322 | struct completion done; | |
1323 | blk_status_t ret; | |
1324 | }; | |
1325 | ||
de671d61 | 1326 | static enum rq_end_io_ret blk_end_sync_rq(struct request *rq, blk_status_t ret) |
32ac5a9b CH |
1327 | { |
1328 | struct blk_rq_wait *wait = rq->end_io_data; | |
1329 | ||
1330 | wait->ret = ret; | |
1331 | complete(&wait->done); | |
de671d61 | 1332 | return RQ_END_IO_NONE; |
32ac5a9b CH |
1333 | } |
1334 | ||
c6e99ea4 | 1335 | bool blk_rq_is_poll(struct request *rq) |
4054cff9 CH |
1336 | { |
1337 | if (!rq->mq_hctx) | |
1338 | return false; | |
1339 | if (rq->mq_hctx->type != HCTX_TYPE_POLL) | |
1340 | return false; | |
4054cff9 CH |
1341 | return true; |
1342 | } | |
c6e99ea4 | 1343 | EXPORT_SYMBOL_GPL(blk_rq_is_poll); |
4054cff9 CH |
1344 | |
1345 | static void blk_rq_poll_completion(struct request *rq, struct completion *wait) | |
1346 | { | |
1347 | do { | |
f6c80cff | 1348 | blk_hctx_poll(rq->q, rq->mq_hctx, NULL, 0); |
4054cff9 CH |
1349 | cond_resched(); |
1350 | } while (!completion_done(wait)); | |
1351 | } | |
1352 | ||
1353 | /** | |
1354 | * blk_execute_rq - insert a request into queue for execution | |
4054cff9 CH |
1355 | * @rq: request to insert |
1356 | * @at_head: insert request at head or tail of queue | |
1357 | * | |
1358 | * Description: | |
1359 | * Insert a fully prepared request at the back of the I/O scheduler queue | |
1360 | * for execution and wait for completion. | |
1361 | * Return: The blk_status_t result provided to blk_mq_end_request(). | |
1362 | */ | |
b84ba30b | 1363 | blk_status_t blk_execute_rq(struct request *rq, bool at_head) |
4054cff9 | 1364 | { |
f0dbe6e8 | 1365 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
32ac5a9b CH |
1366 | struct blk_rq_wait wait = { |
1367 | .done = COMPLETION_INITIALIZER_ONSTACK(wait.done), | |
1368 | }; | |
4054cff9 | 1369 | |
ae948fd6 CH |
1370 | WARN_ON(irqs_disabled()); |
1371 | WARN_ON(!blk_rq_is_passthrough(rq)); | |
4054cff9 CH |
1372 | |
1373 | rq->end_io_data = &wait; | |
ae948fd6 | 1374 | rq->end_io = blk_end_sync_rq; |
4054cff9 | 1375 | |
ae948fd6 | 1376 | blk_account_io_start(rq); |
710fa378 | 1377 | blk_mq_insert_request(rq, at_head ? BLK_MQ_INSERT_AT_HEAD : 0); |
f0dbe6e8 | 1378 | blk_mq_run_hw_queue(hctx, false); |
4054cff9 | 1379 | |
ae948fd6 | 1380 | if (blk_rq_is_poll(rq)) { |
32ac5a9b | 1381 | blk_rq_poll_completion(rq, &wait.done); |
ae948fd6 CH |
1382 | } else { |
1383 | /* | |
1384 | * Prevent hang_check timer from firing at us during very long | |
1385 | * I/O | |
1386 | */ | |
1387 | unsigned long hang_check = sysctl_hung_task_timeout_secs; | |
1388 | ||
1389 | if (hang_check) | |
32ac5a9b | 1390 | while (!wait_for_completion_io_timeout(&wait.done, |
ae948fd6 CH |
1391 | hang_check * (HZ/2))) |
1392 | ; | |
1393 | else | |
32ac5a9b | 1394 | wait_for_completion_io(&wait.done); |
ae948fd6 | 1395 | } |
4054cff9 | 1396 | |
32ac5a9b | 1397 | return wait.ret; |
4054cff9 CH |
1398 | } |
1399 | EXPORT_SYMBOL(blk_execute_rq); | |
1400 | ||
ed0791b2 | 1401 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
1402 | { |
1403 | struct request_queue *q = rq->q; | |
1404 | ||
923218f6 ML |
1405 | blk_mq_put_driver_tag(rq); |
1406 | ||
a54895fa | 1407 | trace_block_rq_requeue(rq); |
a7905043 | 1408 | rq_qos_requeue(q, rq); |
49f5baa5 | 1409 | |
12f5b931 KB |
1410 | if (blk_mq_request_started(rq)) { |
1411 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); | |
da661267 | 1412 | rq->rq_flags &= ~RQF_TIMED_OUT; |
e2490073 | 1413 | } |
320ae51f JA |
1414 | } |
1415 | ||
2b053aca | 1416 | void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list) |
ed0791b2 | 1417 | { |
214a4418 | 1418 | struct request_queue *q = rq->q; |
9a67aa52 | 1419 | unsigned long flags; |
214a4418 | 1420 | |
ed0791b2 | 1421 | __blk_mq_requeue_request(rq); |
ed0791b2 | 1422 | |
105976f5 ML |
1423 | /* this request will be re-inserted to io scheduler queue */ |
1424 | blk_mq_sched_requeue_request(rq); | |
1425 | ||
9a67aa52 CH |
1426 | spin_lock_irqsave(&q->requeue_lock, flags); |
1427 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
1428 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
214a4418 CH |
1429 | |
1430 | if (kick_requeue_list) | |
1431 | blk_mq_kick_requeue_list(q); | |
ed0791b2 CH |
1432 | } |
1433 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
1434 | ||
6fca6a61 CH |
1435 | static void blk_mq_requeue_work(struct work_struct *work) |
1436 | { | |
1437 | struct request_queue *q = | |
2849450a | 1438 | container_of(work, struct request_queue, requeue_work.work); |
6fca6a61 | 1439 | LIST_HEAD(rq_list); |
9a67aa52 CH |
1440 | LIST_HEAD(flush_list); |
1441 | struct request *rq; | |
6fca6a61 | 1442 | |
18e9781d | 1443 | spin_lock_irq(&q->requeue_lock); |
6fca6a61 | 1444 | list_splice_init(&q->requeue_list, &rq_list); |
9a67aa52 | 1445 | list_splice_init(&q->flush_list, &flush_list); |
18e9781d | 1446 | spin_unlock_irq(&q->requeue_lock); |
6fca6a61 | 1447 | |
9a67aa52 CH |
1448 | while (!list_empty(&rq_list)) { |
1449 | rq = list_entry(rq_list.next, struct request, queuelist); | |
aef1897c | 1450 | /* |
a1e948b8 CH |
1451 | * If RQF_DONTPREP ist set, the request has been started by the |
1452 | * driver already and might have driver-specific data allocated | |
1453 | * already. Insert it into the hctx dispatch list to avoid | |
1454 | * block layer merges for the request. | |
aef1897c | 1455 | */ |
a1e948b8 | 1456 | if (rq->rq_flags & RQF_DONTPREP) { |
a1e948b8 | 1457 | list_del_init(&rq->queuelist); |
2b597613 | 1458 | blk_mq_request_bypass_insert(rq, 0); |
9a67aa52 | 1459 | } else { |
a1e948b8 | 1460 | list_del_init(&rq->queuelist); |
710fa378 | 1461 | blk_mq_insert_request(rq, BLK_MQ_INSERT_AT_HEAD); |
a1e948b8 | 1462 | } |
6fca6a61 CH |
1463 | } |
1464 | ||
9a67aa52 CH |
1465 | while (!list_empty(&flush_list)) { |
1466 | rq = list_entry(flush_list.next, struct request, queuelist); | |
6fca6a61 | 1467 | list_del_init(&rq->queuelist); |
710fa378 | 1468 | blk_mq_insert_request(rq, 0); |
6fca6a61 CH |
1469 | } |
1470 | ||
52d7f1b5 | 1471 | blk_mq_run_hw_queues(q, false); |
6fca6a61 CH |
1472 | } |
1473 | ||
6fca6a61 CH |
1474 | void blk_mq_kick_requeue_list(struct request_queue *q) |
1475 | { | |
ae943d20 | 1476 | kblockd_mod_delayed_work_on(WORK_CPU_UNBOUND, &q->requeue_work, 0); |
6fca6a61 CH |
1477 | } |
1478 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
1479 | ||
2849450a MS |
1480 | void blk_mq_delay_kick_requeue_list(struct request_queue *q, |
1481 | unsigned long msecs) | |
1482 | { | |
d4acf365 BVA |
1483 | kblockd_mod_delayed_work_on(WORK_CPU_UNBOUND, &q->requeue_work, |
1484 | msecs_to_jiffies(msecs)); | |
2849450a MS |
1485 | } |
1486 | EXPORT_SYMBOL(blk_mq_delay_kick_requeue_list); | |
1487 | ||
2dd6532e | 1488 | static bool blk_mq_rq_inflight(struct request *rq, void *priv) |
ae879912 JA |
1489 | { |
1490 | /* | |
8ab30a33 JG |
1491 | * If we find a request that isn't idle we know the queue is busy |
1492 | * as it's checked in the iter. | |
1493 | * Return false to stop the iteration. | |
ae879912 | 1494 | */ |
8ab30a33 | 1495 | if (blk_mq_request_started(rq)) { |
ae879912 JA |
1496 | bool *busy = priv; |
1497 | ||
1498 | *busy = true; | |
1499 | return false; | |
1500 | } | |
1501 | ||
1502 | return true; | |
1503 | } | |
1504 | ||
3c94d83c | 1505 | bool blk_mq_queue_inflight(struct request_queue *q) |
ae879912 JA |
1506 | { |
1507 | bool busy = false; | |
1508 | ||
3c94d83c | 1509 | blk_mq_queue_tag_busy_iter(q, blk_mq_rq_inflight, &busy); |
ae879912 JA |
1510 | return busy; |
1511 | } | |
3c94d83c | 1512 | EXPORT_SYMBOL_GPL(blk_mq_queue_inflight); |
ae879912 | 1513 | |
9bdb4833 | 1514 | static void blk_mq_rq_timed_out(struct request *req) |
320ae51f | 1515 | { |
da661267 | 1516 | req->rq_flags |= RQF_TIMED_OUT; |
d1210d5a CH |
1517 | if (req->q->mq_ops->timeout) { |
1518 | enum blk_eh_timer_return ret; | |
1519 | ||
9bdb4833 | 1520 | ret = req->q->mq_ops->timeout(req); |
d1210d5a CH |
1521 | if (ret == BLK_EH_DONE) |
1522 | return; | |
1523 | WARN_ON_ONCE(ret != BLK_EH_RESET_TIMER); | |
46f92d42 | 1524 | } |
d1210d5a CH |
1525 | |
1526 | blk_add_timer(req); | |
87ee7b11 | 1527 | } |
5b3f25fc | 1528 | |
82c22947 DJ |
1529 | struct blk_expired_data { |
1530 | bool has_timedout_rq; | |
1531 | unsigned long next; | |
1532 | unsigned long timeout_start; | |
1533 | }; | |
1534 | ||
1535 | static bool blk_mq_req_expired(struct request *rq, struct blk_expired_data *expired) | |
81481eb4 | 1536 | { |
12f5b931 | 1537 | unsigned long deadline; |
87ee7b11 | 1538 | |
12f5b931 KB |
1539 | if (blk_mq_rq_state(rq) != MQ_RQ_IN_FLIGHT) |
1540 | return false; | |
da661267 CH |
1541 | if (rq->rq_flags & RQF_TIMED_OUT) |
1542 | return false; | |
a7af0af3 | 1543 | |
079076b3 | 1544 | deadline = READ_ONCE(rq->deadline); |
82c22947 | 1545 | if (time_after_eq(expired->timeout_start, deadline)) |
12f5b931 | 1546 | return true; |
a7af0af3 | 1547 | |
82c22947 DJ |
1548 | if (expired->next == 0) |
1549 | expired->next = deadline; | |
1550 | else if (time_after(expired->next, deadline)) | |
1551 | expired->next = deadline; | |
12f5b931 | 1552 | return false; |
87ee7b11 JA |
1553 | } |
1554 | ||
2e315dc0 ML |
1555 | void blk_mq_put_rq_ref(struct request *rq) |
1556 | { | |
de671d61 JA |
1557 | if (is_flush_rq(rq)) { |
1558 | if (rq->end_io(rq, 0) == RQ_END_IO_FREE) | |
1559 | blk_mq_free_request(rq); | |
1560 | } else if (req_ref_put_and_test(rq)) { | |
2e315dc0 | 1561 | __blk_mq_free_request(rq); |
de671d61 | 1562 | } |
2e315dc0 ML |
1563 | } |
1564 | ||
2dd6532e | 1565 | static bool blk_mq_check_expired(struct request *rq, void *priv) |
1d9bd516 | 1566 | { |
82c22947 | 1567 | struct blk_expired_data *expired = priv; |
12f5b931 KB |
1568 | |
1569 | /* | |
c797b40c ML |
1570 | * blk_mq_queue_tag_busy_iter() has locked the request, so it cannot |
1571 | * be reallocated underneath the timeout handler's processing, then | |
1572 | * the expire check is reliable. If the request is not expired, then | |
1573 | * it was completed and reallocated as a new request after returning | |
1574 | * from blk_mq_check_expired(). | |
1d9bd516 | 1575 | */ |
82c22947 DJ |
1576 | if (blk_mq_req_expired(rq, expired)) { |
1577 | expired->has_timedout_rq = true; | |
1578 | return false; | |
1579 | } | |
1580 | return true; | |
1581 | } | |
1582 | ||
1583 | static bool blk_mq_handle_expired(struct request *rq, void *priv) | |
1584 | { | |
1585 | struct blk_expired_data *expired = priv; | |
1586 | ||
1587 | if (blk_mq_req_expired(rq, expired)) | |
9bdb4833 | 1588 | blk_mq_rq_timed_out(rq); |
7baa8572 | 1589 | return true; |
1d9bd516 TH |
1590 | } |
1591 | ||
287922eb | 1592 | static void blk_mq_timeout_work(struct work_struct *work) |
320ae51f | 1593 | { |
287922eb CH |
1594 | struct request_queue *q = |
1595 | container_of(work, struct request_queue, timeout_work); | |
82c22947 DJ |
1596 | struct blk_expired_data expired = { |
1597 | .timeout_start = jiffies, | |
1598 | }; | |
1d9bd516 | 1599 | struct blk_mq_hw_ctx *hctx; |
4f481208 | 1600 | unsigned long i; |
320ae51f | 1601 | |
71f79fb3 GKB |
1602 | /* A deadlock might occur if a request is stuck requiring a |
1603 | * timeout at the same time a queue freeze is waiting | |
1604 | * completion, since the timeout code would not be able to | |
1605 | * acquire the queue reference here. | |
1606 | * | |
1607 | * That's why we don't use blk_queue_enter here; instead, we use | |
1608 | * percpu_ref_tryget directly, because we need to be able to | |
1609 | * obtain a reference even in the short window between the queue | |
1610 | * starting to freeze, by dropping the first reference in | |
1671d522 | 1611 | * blk_freeze_queue_start, and the moment the last request is |
71f79fb3 GKB |
1612 | * consumed, marked by the instant q_usage_counter reaches |
1613 | * zero. | |
1614 | */ | |
1615 | if (!percpu_ref_tryget(&q->q_usage_counter)) | |
287922eb CH |
1616 | return; |
1617 | ||
82c22947 DJ |
1618 | /* check if there is any timed-out request */ |
1619 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &expired); | |
1620 | if (expired.has_timedout_rq) { | |
1621 | /* | |
1622 | * Before walking tags, we must ensure any submit started | |
1623 | * before the current time has finished. Since the submit | |
1624 | * uses srcu or rcu, wait for a synchronization point to | |
1625 | * ensure all running submits have finished | |
1626 | */ | |
483239c7 | 1627 | blk_mq_wait_quiesce_done(q->tag_set); |
82c22947 DJ |
1628 | |
1629 | expired.next = 0; | |
1630 | blk_mq_queue_tag_busy_iter(q, blk_mq_handle_expired, &expired); | |
1631 | } | |
320ae51f | 1632 | |
82c22947 DJ |
1633 | if (expired.next != 0) { |
1634 | mod_timer(&q->timeout, expired.next); | |
0d2602ca | 1635 | } else { |
fcd36c36 BVA |
1636 | /* |
1637 | * Request timeouts are handled as a forward rolling timer. If | |
1638 | * we end up here it means that no requests are pending and | |
1639 | * also that no request has been pending for a while. Mark | |
1640 | * each hctx as idle. | |
1641 | */ | |
f054b56c ML |
1642 | queue_for_each_hw_ctx(q, hctx, i) { |
1643 | /* the hctx may be unmapped, so check it here */ | |
1644 | if (blk_mq_hw_queue_mapped(hctx)) | |
1645 | blk_mq_tag_idle(hctx); | |
1646 | } | |
0d2602ca | 1647 | } |
287922eb | 1648 | blk_queue_exit(q); |
320ae51f JA |
1649 | } |
1650 | ||
88459642 OS |
1651 | struct flush_busy_ctx_data { |
1652 | struct blk_mq_hw_ctx *hctx; | |
1653 | struct list_head *list; | |
1654 | }; | |
1655 | ||
1656 | static bool flush_busy_ctx(struct sbitmap *sb, unsigned int bitnr, void *data) | |
1657 | { | |
1658 | struct flush_busy_ctx_data *flush_data = data; | |
1659 | struct blk_mq_hw_ctx *hctx = flush_data->hctx; | |
1660 | struct blk_mq_ctx *ctx = hctx->ctxs[bitnr]; | |
c16d6b5a | 1661 | enum hctx_type type = hctx->type; |
88459642 | 1662 | |
88459642 | 1663 | spin_lock(&ctx->lock); |
c16d6b5a | 1664 | list_splice_tail_init(&ctx->rq_lists[type], flush_data->list); |
e9a99a63 | 1665 | sbitmap_clear_bit(sb, bitnr); |
88459642 OS |
1666 | spin_unlock(&ctx->lock); |
1667 | return true; | |
1668 | } | |
1669 | ||
1429d7c9 JA |
1670 | /* |
1671 | * Process software queues that have been marked busy, splicing them | |
1672 | * to the for-dispatch | |
1673 | */ | |
2c3ad667 | 1674 | void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) |
1429d7c9 | 1675 | { |
88459642 OS |
1676 | struct flush_busy_ctx_data data = { |
1677 | .hctx = hctx, | |
1678 | .list = list, | |
1679 | }; | |
1429d7c9 | 1680 | |
88459642 | 1681 | sbitmap_for_each_set(&hctx->ctx_map, flush_busy_ctx, &data); |
1429d7c9 | 1682 | } |
2c3ad667 | 1683 | EXPORT_SYMBOL_GPL(blk_mq_flush_busy_ctxs); |
1429d7c9 | 1684 | |
b347689f ML |
1685 | struct dispatch_rq_data { |
1686 | struct blk_mq_hw_ctx *hctx; | |
1687 | struct request *rq; | |
1688 | }; | |
1689 | ||
1690 | static bool dispatch_rq_from_ctx(struct sbitmap *sb, unsigned int bitnr, | |
1691 | void *data) | |
1692 | { | |
1693 | struct dispatch_rq_data *dispatch_data = data; | |
1694 | struct blk_mq_hw_ctx *hctx = dispatch_data->hctx; | |
1695 | struct blk_mq_ctx *ctx = hctx->ctxs[bitnr]; | |
c16d6b5a | 1696 | enum hctx_type type = hctx->type; |
b347689f ML |
1697 | |
1698 | spin_lock(&ctx->lock); | |
c16d6b5a ML |
1699 | if (!list_empty(&ctx->rq_lists[type])) { |
1700 | dispatch_data->rq = list_entry_rq(ctx->rq_lists[type].next); | |
b347689f | 1701 | list_del_init(&dispatch_data->rq->queuelist); |
c16d6b5a | 1702 | if (list_empty(&ctx->rq_lists[type])) |
b347689f ML |
1703 | sbitmap_clear_bit(sb, bitnr); |
1704 | } | |
1705 | spin_unlock(&ctx->lock); | |
1706 | ||
1707 | return !dispatch_data->rq; | |
1708 | } | |
1709 | ||
1710 | struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx, | |
1711 | struct blk_mq_ctx *start) | |
1712 | { | |
f31967f0 | 1713 | unsigned off = start ? start->index_hw[hctx->type] : 0; |
b347689f ML |
1714 | struct dispatch_rq_data data = { |
1715 | .hctx = hctx, | |
1716 | .rq = NULL, | |
1717 | }; | |
1718 | ||
1719 | __sbitmap_for_each_set(&hctx->ctx_map, off, | |
1720 | dispatch_rq_from_ctx, &data); | |
1721 | ||
1722 | return data.rq; | |
1723 | } | |
1724 | ||
a808a9d5 | 1725 | static bool __blk_mq_alloc_driver_tag(struct request *rq) |
570e9b73 | 1726 | { |
ae0f1a73 | 1727 | struct sbitmap_queue *bt = &rq->mq_hctx->tags->bitmap_tags; |
570e9b73 | 1728 | unsigned int tag_offset = rq->mq_hctx->tags->nr_reserved_tags; |
570e9b73 ML |
1729 | int tag; |
1730 | ||
568f2700 ML |
1731 | blk_mq_tag_busy(rq->mq_hctx); |
1732 | ||
570e9b73 | 1733 | if (blk_mq_tag_is_reserved(rq->mq_hctx->sched_tags, rq->internal_tag)) { |
ae0f1a73 | 1734 | bt = &rq->mq_hctx->tags->breserved_tags; |
570e9b73 | 1735 | tag_offset = 0; |
28500850 ML |
1736 | } else { |
1737 | if (!hctx_may_queue(rq->mq_hctx, bt)) | |
1738 | return false; | |
570e9b73 ML |
1739 | } |
1740 | ||
570e9b73 ML |
1741 | tag = __sbitmap_queue_get(bt); |
1742 | if (tag == BLK_MQ_NO_TAG) | |
1743 | return false; | |
1744 | ||
1745 | rq->tag = tag + tag_offset; | |
570e9b73 ML |
1746 | return true; |
1747 | } | |
1748 | ||
a808a9d5 | 1749 | bool __blk_mq_get_driver_tag(struct blk_mq_hw_ctx *hctx, struct request *rq) |
570e9b73 | 1750 | { |
a808a9d5 | 1751 | if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_alloc_driver_tag(rq)) |
568f2700 ML |
1752 | return false; |
1753 | ||
51db1c37 | 1754 | if ((hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) && |
568f2700 ML |
1755 | !(rq->rq_flags & RQF_MQ_INFLIGHT)) { |
1756 | rq->rq_flags |= RQF_MQ_INFLIGHT; | |
bccf5e26 | 1757 | __blk_mq_inc_active_requests(hctx); |
568f2700 ML |
1758 | } |
1759 | hctx->tags->rqs[rq->tag] = rq; | |
1760 | return true; | |
570e9b73 ML |
1761 | } |
1762 | ||
eb619fdb JA |
1763 | static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, |
1764 | int flags, void *key) | |
da55f2cc OS |
1765 | { |
1766 | struct blk_mq_hw_ctx *hctx; | |
1767 | ||
1768 | hctx = container_of(wait, struct blk_mq_hw_ctx, dispatch_wait); | |
1769 | ||
5815839b | 1770 | spin_lock(&hctx->dispatch_wait_lock); |
e8618575 JA |
1771 | if (!list_empty(&wait->entry)) { |
1772 | struct sbitmap_queue *sbq; | |
1773 | ||
1774 | list_del_init(&wait->entry); | |
ae0f1a73 | 1775 | sbq = &hctx->tags->bitmap_tags; |
e8618575 JA |
1776 | atomic_dec(&sbq->ws_active); |
1777 | } | |
5815839b ML |
1778 | spin_unlock(&hctx->dispatch_wait_lock); |
1779 | ||
da55f2cc OS |
1780 | blk_mq_run_hw_queue(hctx, true); |
1781 | return 1; | |
1782 | } | |
1783 | ||
f906a6a0 JA |
1784 | /* |
1785 | * Mark us waiting for a tag. For shared tags, this involves hooking us into | |
ee3e4de5 BVA |
1786 | * the tag wakeups. For non-shared tags, we can simply mark us needing a |
1787 | * restart. For both cases, take care to check the condition again after | |
f906a6a0 JA |
1788 | * marking us as waiting. |
1789 | */ | |
2278d69f | 1790 | static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx, |
f906a6a0 | 1791 | struct request *rq) |
da55f2cc | 1792 | { |
98b99e94 | 1793 | struct sbitmap_queue *sbq; |
5815839b | 1794 | struct wait_queue_head *wq; |
f906a6a0 JA |
1795 | wait_queue_entry_t *wait; |
1796 | bool ret; | |
da55f2cc | 1797 | |
47df9ce9 KS |
1798 | if (!(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) && |
1799 | !(blk_mq_is_shared_tags(hctx->flags))) { | |
684b7324 | 1800 | blk_mq_sched_mark_restart_hctx(hctx); |
f906a6a0 | 1801 | |
c27d53fb BVA |
1802 | /* |
1803 | * It's possible that a tag was freed in the window between the | |
1804 | * allocation failure and adding the hardware queue to the wait | |
1805 | * queue. | |
1806 | * | |
1807 | * Don't clear RESTART here, someone else could have set it. | |
1808 | * At most this will cost an extra queue run. | |
1809 | */ | |
8ab6bb9e | 1810 | return blk_mq_get_driver_tag(rq); |
eb619fdb | 1811 | } |
eb619fdb | 1812 | |
2278d69f | 1813 | wait = &hctx->dispatch_wait; |
c27d53fb BVA |
1814 | if (!list_empty_careful(&wait->entry)) |
1815 | return false; | |
1816 | ||
98b99e94 KS |
1817 | if (blk_mq_tag_is_reserved(rq->mq_hctx->sched_tags, rq->internal_tag)) |
1818 | sbq = &hctx->tags->breserved_tags; | |
1819 | else | |
1820 | sbq = &hctx->tags->bitmap_tags; | |
e8618575 | 1821 | wq = &bt_wait_ptr(sbq, hctx)->wait; |
5815839b ML |
1822 | |
1823 | spin_lock_irq(&wq->lock); | |
1824 | spin_lock(&hctx->dispatch_wait_lock); | |
c27d53fb | 1825 | if (!list_empty(&wait->entry)) { |
5815839b ML |
1826 | spin_unlock(&hctx->dispatch_wait_lock); |
1827 | spin_unlock_irq(&wq->lock); | |
c27d53fb | 1828 | return false; |
eb619fdb JA |
1829 | } |
1830 | ||
e8618575 | 1831 | atomic_inc(&sbq->ws_active); |
5815839b ML |
1832 | wait->flags &= ~WQ_FLAG_EXCLUSIVE; |
1833 | __add_wait_queue(wq, wait); | |
c27d53fb | 1834 | |
da55f2cc | 1835 | /* |
eb619fdb JA |
1836 | * It's possible that a tag was freed in the window between the |
1837 | * allocation failure and adding the hardware queue to the wait | |
1838 | * queue. | |
da55f2cc | 1839 | */ |
8ab6bb9e | 1840 | ret = blk_mq_get_driver_tag(rq); |
c27d53fb | 1841 | if (!ret) { |
5815839b ML |
1842 | spin_unlock(&hctx->dispatch_wait_lock); |
1843 | spin_unlock_irq(&wq->lock); | |
c27d53fb | 1844 | return false; |
eb619fdb | 1845 | } |
c27d53fb BVA |
1846 | |
1847 | /* | |
1848 | * We got a tag, remove ourselves from the wait queue to ensure | |
1849 | * someone else gets the wakeup. | |
1850 | */ | |
c27d53fb | 1851 | list_del_init(&wait->entry); |
e8618575 | 1852 | atomic_dec(&sbq->ws_active); |
5815839b ML |
1853 | spin_unlock(&hctx->dispatch_wait_lock); |
1854 | spin_unlock_irq(&wq->lock); | |
c27d53fb BVA |
1855 | |
1856 | return true; | |
da55f2cc OS |
1857 | } |
1858 | ||
6e768717 ML |
1859 | #define BLK_MQ_DISPATCH_BUSY_EWMA_WEIGHT 8 |
1860 | #define BLK_MQ_DISPATCH_BUSY_EWMA_FACTOR 4 | |
1861 | /* | |
1862 | * Update dispatch busy with the Exponential Weighted Moving Average(EWMA): | |
1863 | * - EWMA is one simple way to compute running average value | |
1864 | * - weight(7/8 and 1/8) is applied so that it can decrease exponentially | |
1865 | * - take 4 as factor for avoiding to get too small(0) result, and this | |
1866 | * factor doesn't matter because EWMA decreases exponentially | |
1867 | */ | |
1868 | static void blk_mq_update_dispatch_busy(struct blk_mq_hw_ctx *hctx, bool busy) | |
1869 | { | |
1870 | unsigned int ewma; | |
1871 | ||
6e768717 ML |
1872 | ewma = hctx->dispatch_busy; |
1873 | ||
1874 | if (!ewma && !busy) | |
1875 | return; | |
1876 | ||
1877 | ewma *= BLK_MQ_DISPATCH_BUSY_EWMA_WEIGHT - 1; | |
1878 | if (busy) | |
1879 | ewma += 1 << BLK_MQ_DISPATCH_BUSY_EWMA_FACTOR; | |
1880 | ewma /= BLK_MQ_DISPATCH_BUSY_EWMA_WEIGHT; | |
1881 | ||
1882 | hctx->dispatch_busy = ewma; | |
1883 | } | |
1884 | ||
86ff7c2a ML |
1885 | #define BLK_MQ_RESOURCE_DELAY 3 /* ms units */ |
1886 | ||
c92a4103 JT |
1887 | static void blk_mq_handle_dev_resource(struct request *rq, |
1888 | struct list_head *list) | |
1889 | { | |
c92a4103 JT |
1890 | list_add(&rq->queuelist, list); |
1891 | __blk_mq_requeue_request(rq); | |
1892 | } | |
1893 | ||
0512a75b KB |
1894 | static void blk_mq_handle_zone_resource(struct request *rq, |
1895 | struct list_head *zone_list) | |
1896 | { | |
1897 | /* | |
1898 | * If we end up here it is because we cannot dispatch a request to a | |
1899 | * specific zone due to LLD level zone-write locking or other zone | |
1900 | * related resource not being available. In this case, set the request | |
1901 | * aside in zone_list for retrying it later. | |
1902 | */ | |
1903 | list_add(&rq->queuelist, zone_list); | |
1904 | __blk_mq_requeue_request(rq); | |
1905 | } | |
1906 | ||
75383524 ML |
1907 | enum prep_dispatch { |
1908 | PREP_DISPATCH_OK, | |
1909 | PREP_DISPATCH_NO_TAG, | |
1910 | PREP_DISPATCH_NO_BUDGET, | |
1911 | }; | |
1912 | ||
1913 | static enum prep_dispatch blk_mq_prep_dispatch_rq(struct request *rq, | |
1914 | bool need_budget) | |
1915 | { | |
1916 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; | |
2a5a24aa | 1917 | int budget_token = -1; |
75383524 | 1918 | |
2a5a24aa ML |
1919 | if (need_budget) { |
1920 | budget_token = blk_mq_get_dispatch_budget(rq->q); | |
1921 | if (budget_token < 0) { | |
1922 | blk_mq_put_driver_tag(rq); | |
1923 | return PREP_DISPATCH_NO_BUDGET; | |
1924 | } | |
1925 | blk_mq_set_rq_budget_token(rq, budget_token); | |
75383524 ML |
1926 | } |
1927 | ||
1928 | if (!blk_mq_get_driver_tag(rq)) { | |
1929 | /* | |
1930 | * The initial allocation attempt failed, so we need to | |
1931 | * rerun the hardware queue when a tag is freed. The | |
1932 | * waitqueue takes care of that. If the queue is run | |
1933 | * before we add this entry back on the dispatch list, | |
1934 | * we'll re-run it below. | |
1935 | */ | |
1936 | if (!blk_mq_mark_tag_wait(hctx, rq)) { | |
1fd40b5e ML |
1937 | /* |
1938 | * All budgets not got from this function will be put | |
1939 | * together during handling partial dispatch | |
1940 | */ | |
1941 | if (need_budget) | |
2a5a24aa | 1942 | blk_mq_put_dispatch_budget(rq->q, budget_token); |
75383524 ML |
1943 | return PREP_DISPATCH_NO_TAG; |
1944 | } | |
1945 | } | |
1946 | ||
1947 | return PREP_DISPATCH_OK; | |
1948 | } | |
1949 | ||
1fd40b5e ML |
1950 | /* release all allocated budgets before calling to blk_mq_dispatch_rq_list */ |
1951 | static void blk_mq_release_budgets(struct request_queue *q, | |
2a5a24aa | 1952 | struct list_head *list) |
1fd40b5e | 1953 | { |
2a5a24aa | 1954 | struct request *rq; |
1fd40b5e | 1955 | |
2a5a24aa ML |
1956 | list_for_each_entry(rq, list, queuelist) { |
1957 | int budget_token = blk_mq_get_rq_budget_token(rq); | |
1fd40b5e | 1958 | |
2a5a24aa ML |
1959 | if (budget_token >= 0) |
1960 | blk_mq_put_dispatch_budget(q, budget_token); | |
1961 | } | |
1fd40b5e ML |
1962 | } |
1963 | ||
34c9f547 KS |
1964 | /* |
1965 | * blk_mq_commit_rqs will notify driver using bd->last that there is no | |
1966 | * more requests. (See comment in struct blk_mq_ops for commit_rqs for | |
1967 | * details) | |
1968 | * Attention, we should explicitly call this in unusual cases: | |
1969 | * 1) did not queue everything initially scheduled to queue | |
1970 | * 2) the last attempt to queue a request failed | |
1971 | */ | |
1972 | static void blk_mq_commit_rqs(struct blk_mq_hw_ctx *hctx, int queued, | |
1973 | bool from_schedule) | |
1974 | { | |
1975 | if (hctx->queue->mq_ops->commit_rqs && queued) { | |
1976 | trace_block_unplug(hctx->queue, queued, !from_schedule); | |
1977 | hctx->queue->mq_ops->commit_rqs(hctx); | |
1978 | } | |
1979 | } | |
1980 | ||
1f57f8d4 JA |
1981 | /* |
1982 | * Returns true if we did some work AND can potentially do more. | |
1983 | */ | |
445874e8 | 1984 | bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, |
1fd40b5e | 1985 | unsigned int nr_budgets) |
320ae51f | 1986 | { |
75383524 | 1987 | enum prep_dispatch prep; |
445874e8 | 1988 | struct request_queue *q = hctx->queue; |
f1ce99f7 | 1989 | struct request *rq; |
4ea58fe4 | 1990 | int queued; |
86ff7c2a | 1991 | blk_status_t ret = BLK_STS_OK; |
0512a75b | 1992 | LIST_HEAD(zone_list); |
9586e67b | 1993 | bool needs_resource = false; |
320ae51f | 1994 | |
81380ca1 OS |
1995 | if (list_empty(list)) |
1996 | return false; | |
1997 | ||
320ae51f JA |
1998 | /* |
1999 | * Now process all the entries, sending them to the driver. | |
2000 | */ | |
4ea58fe4 | 2001 | queued = 0; |
81380ca1 | 2002 | do { |
74c45052 | 2003 | struct blk_mq_queue_data bd; |
320ae51f | 2004 | |
f04c3df3 | 2005 | rq = list_first_entry(list, struct request, queuelist); |
0bca799b | 2006 | |
445874e8 | 2007 | WARN_ON_ONCE(hctx != rq->mq_hctx); |
1fd40b5e | 2008 | prep = blk_mq_prep_dispatch_rq(rq, !nr_budgets); |
75383524 | 2009 | if (prep != PREP_DISPATCH_OK) |
0bca799b | 2010 | break; |
de148297 | 2011 | |
320ae51f | 2012 | list_del_init(&rq->queuelist); |
320ae51f | 2013 | |
74c45052 | 2014 | bd.rq = rq; |
f1ce99f7 | 2015 | bd.last = list_empty(list); |
74c45052 | 2016 | |
1fd40b5e ML |
2017 | /* |
2018 | * once the request is queued to lld, no need to cover the | |
2019 | * budget any more | |
2020 | */ | |
2021 | if (nr_budgets) | |
2022 | nr_budgets--; | |
74c45052 | 2023 | ret = q->mq_ops->queue_rq(hctx, &bd); |
7bf13729 ML |
2024 | switch (ret) { |
2025 | case BLK_STS_OK: | |
2026 | queued++; | |
320ae51f | 2027 | break; |
7bf13729 | 2028 | case BLK_STS_RESOURCE: |
9586e67b NA |
2029 | needs_resource = true; |
2030 | fallthrough; | |
7bf13729 ML |
2031 | case BLK_STS_DEV_RESOURCE: |
2032 | blk_mq_handle_dev_resource(rq, list); | |
2033 | goto out; | |
2034 | case BLK_STS_ZONE_RESOURCE: | |
0512a75b KB |
2035 | /* |
2036 | * Move the request to zone_list and keep going through | |
2037 | * the dispatch list to find more requests the drive can | |
2038 | * accept. | |
2039 | */ | |
2040 | blk_mq_handle_zone_resource(rq, &zone_list); | |
9586e67b | 2041 | needs_resource = true; |
7bf13729 ML |
2042 | break; |
2043 | default: | |
e21ee5a6 | 2044 | blk_mq_end_request(rq, ret); |
320ae51f | 2045 | } |
81380ca1 | 2046 | } while (!list_empty(list)); |
7bf13729 | 2047 | out: |
0512a75b KB |
2048 | if (!list_empty(&zone_list)) |
2049 | list_splice_tail_init(&zone_list, list); | |
2050 | ||
632bfb63 | 2051 | /* If we didn't flush the entire list, we could have told the driver |
2052 | * there was more coming, but that turned out to be a lie. | |
2053 | */ | |
e4ef2e05 KS |
2054 | if (!list_empty(list) || ret != BLK_STS_OK) |
2055 | blk_mq_commit_rqs(hctx, queued, false); | |
2056 | ||
320ae51f JA |
2057 | /* |
2058 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
2059 | * that is where we will continue on next queue run. | |
2060 | */ | |
f04c3df3 | 2061 | if (!list_empty(list)) { |
86ff7c2a | 2062 | bool needs_restart; |
75383524 ML |
2063 | /* For non-shared tags, the RESTART check will suffice */ |
2064 | bool no_tag = prep == PREP_DISPATCH_NO_TAG && | |
47df9ce9 KS |
2065 | ((hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) || |
2066 | blk_mq_is_shared_tags(hctx->flags)); | |
86ff7c2a | 2067 | |
2a5a24aa ML |
2068 | if (nr_budgets) |
2069 | blk_mq_release_budgets(q, list); | |
86ff7c2a | 2070 | |
320ae51f | 2071 | spin_lock(&hctx->lock); |
01e99aec | 2072 | list_splice_tail_init(list, &hctx->dispatch); |
320ae51f | 2073 | spin_unlock(&hctx->lock); |
f04c3df3 | 2074 | |
d7d8535f ML |
2075 | /* |
2076 | * Order adding requests to hctx->dispatch and checking | |
2077 | * SCHED_RESTART flag. The pair of this smp_mb() is the one | |
2078 | * in blk_mq_sched_restart(). Avoid restart code path to | |
2079 | * miss the new added requests to hctx->dispatch, meantime | |
2080 | * SCHED_RESTART is observed here. | |
2081 | */ | |
2082 | smp_mb(); | |
2083 | ||
9ba52e58 | 2084 | /* |
710c785f BVA |
2085 | * If SCHED_RESTART was set by the caller of this function and |
2086 | * it is no longer set that means that it was cleared by another | |
2087 | * thread and hence that a queue rerun is needed. | |
9ba52e58 | 2088 | * |
eb619fdb JA |
2089 | * If 'no_tag' is set, that means that we failed getting |
2090 | * a driver tag with an I/O scheduler attached. If our dispatch | |
2091 | * waitqueue is no longer active, ensure that we run the queue | |
2092 | * AFTER adding our entries back to the list. | |
bd166ef1 | 2093 | * |
710c785f BVA |
2094 | * If no I/O scheduler has been configured it is possible that |
2095 | * the hardware queue got stopped and restarted before requests | |
2096 | * were pushed back onto the dispatch list. Rerun the queue to | |
2097 | * avoid starvation. Notes: | |
2098 | * - blk_mq_run_hw_queue() checks whether or not a queue has | |
2099 | * been stopped before rerunning a queue. | |
2100 | * - Some but not all block drivers stop a queue before | |
fc17b653 | 2101 | * returning BLK_STS_RESOURCE. Two exceptions are scsi-mq |
710c785f | 2102 | * and dm-rq. |
86ff7c2a ML |
2103 | * |
2104 | * If driver returns BLK_STS_RESOURCE and SCHED_RESTART | |
2105 | * bit is set, run queue after a delay to avoid IO stalls | |
ab3cee37 | 2106 | * that could otherwise occur if the queue is idle. We'll do |
9586e67b NA |
2107 | * similar if we couldn't get budget or couldn't lock a zone |
2108 | * and SCHED_RESTART is set. | |
bd166ef1 | 2109 | */ |
86ff7c2a | 2110 | needs_restart = blk_mq_sched_needs_restart(hctx); |
9586e67b NA |
2111 | if (prep == PREP_DISPATCH_NO_BUDGET) |
2112 | needs_resource = true; | |
86ff7c2a | 2113 | if (!needs_restart || |
eb619fdb | 2114 | (no_tag && list_empty_careful(&hctx->dispatch_wait.entry))) |
bd166ef1 | 2115 | blk_mq_run_hw_queue(hctx, true); |
6d5e8d21 | 2116 | else if (needs_resource) |
86ff7c2a | 2117 | blk_mq_delay_run_hw_queue(hctx, BLK_MQ_RESOURCE_DELAY); |
1f57f8d4 | 2118 | |
6e768717 | 2119 | blk_mq_update_dispatch_busy(hctx, true); |
1f57f8d4 | 2120 | return false; |
4ea58fe4 | 2121 | } |
f04c3df3 | 2122 | |
4ea58fe4 KS |
2123 | blk_mq_update_dispatch_busy(hctx, false); |
2124 | return true; | |
f04c3df3 JA |
2125 | } |
2126 | ||
f82ddf19 ML |
2127 | static inline int blk_mq_first_mapped_cpu(struct blk_mq_hw_ctx *hctx) |
2128 | { | |
2129 | int cpu = cpumask_first_and(hctx->cpumask, cpu_online_mask); | |
2130 | ||
2131 | if (cpu >= nr_cpu_ids) | |
2132 | cpu = cpumask_first(hctx->cpumask); | |
2133 | return cpu; | |
2134 | } | |
2135 | ||
506e931f JA |
2136 | /* |
2137 | * It'd be great if the workqueue API had a way to pass | |
2138 | * in a mask and had some smarts for more clever placement. | |
2139 | * For now we just round-robin here, switching for every | |
2140 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
2141 | */ | |
2142 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
2143 | { | |
7bed4595 | 2144 | bool tried = false; |
476f8c98 | 2145 | int next_cpu = hctx->next_cpu; |
7bed4595 | 2146 | |
b657d7e6 CH |
2147 | if (hctx->queue->nr_hw_queues == 1) |
2148 | return WORK_CPU_UNBOUND; | |
506e931f JA |
2149 | |
2150 | if (--hctx->next_cpu_batch <= 0) { | |
7bed4595 | 2151 | select_cpu: |
476f8c98 | 2152 | next_cpu = cpumask_next_and(next_cpu, hctx->cpumask, |
20e4d813 | 2153 | cpu_online_mask); |
506e931f | 2154 | if (next_cpu >= nr_cpu_ids) |
f82ddf19 | 2155 | next_cpu = blk_mq_first_mapped_cpu(hctx); |
506e931f JA |
2156 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; |
2157 | } | |
2158 | ||
7bed4595 ML |
2159 | /* |
2160 | * Do unbound schedule if we can't find a online CPU for this hctx, | |
2161 | * and it should only happen in the path of handling CPU DEAD. | |
2162 | */ | |
476f8c98 | 2163 | if (!cpu_online(next_cpu)) { |
7bed4595 ML |
2164 | if (!tried) { |
2165 | tried = true; | |
2166 | goto select_cpu; | |
2167 | } | |
2168 | ||
2169 | /* | |
2170 | * Make sure to re-select CPU next time once after CPUs | |
2171 | * in hctx->cpumask become online again. | |
2172 | */ | |
476f8c98 | 2173 | hctx->next_cpu = next_cpu; |
7bed4595 ML |
2174 | hctx->next_cpu_batch = 1; |
2175 | return WORK_CPU_UNBOUND; | |
2176 | } | |
476f8c98 ML |
2177 | |
2178 | hctx->next_cpu = next_cpu; | |
2179 | return next_cpu; | |
506e931f JA |
2180 | } |
2181 | ||
105663f7 | 2182 | /** |
1aa8d875 | 2183 | * blk_mq_delay_run_hw_queue - Run a hardware queue asynchronously. |
105663f7 | 2184 | * @hctx: Pointer to the hardware queue to run. |
fa94ba8a | 2185 | * @msecs: Milliseconds of delay to wait before running the queue. |
105663f7 | 2186 | * |
1aa8d875 | 2187 | * Run a hardware queue asynchronously with a delay of @msecs. |
105663f7 | 2188 | */ |
1aa8d875 | 2189 | void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) |
320ae51f | 2190 | { |
5435c023 | 2191 | if (unlikely(blk_mq_hctx_stopped(hctx))) |
320ae51f | 2192 | return; |
ae943d20 BVA |
2193 | kblockd_mod_delayed_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work, |
2194 | msecs_to_jiffies(msecs)); | |
7587a5ae | 2195 | } |
7587a5ae BVA |
2196 | EXPORT_SYMBOL(blk_mq_delay_run_hw_queue); |
2197 | ||
105663f7 AA |
2198 | /** |
2199 | * blk_mq_run_hw_queue - Start to run a hardware queue. | |
2200 | * @hctx: Pointer to the hardware queue to run. | |
2201 | * @async: If we want to run the queue asynchronously. | |
2202 | * | |
2203 | * Check if the request queue is not in a quiesced state and if there are | |
2204 | * pending requests to be sent. If this is true, run the queue to send requests | |
2205 | * to hardware. | |
2206 | */ | |
626fb735 | 2207 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
7587a5ae | 2208 | { |
24f5a90f ML |
2209 | bool need_run; |
2210 | ||
4d5bba5b CH |
2211 | /* |
2212 | * We can't run the queue inline with interrupts disabled. | |
2213 | */ | |
2214 | WARN_ON_ONCE(!async && in_interrupt()); | |
2215 | ||
24f5a90f ML |
2216 | /* |
2217 | * When queue is quiesced, we may be switching io scheduler, or | |
2218 | * updating nr_hw_queues, or other things, and we can't run queue | |
2219 | * any more, even __blk_mq_hctx_has_pending() can't be called safely. | |
2220 | * | |
2221 | * And queue will be rerun in blk_mq_unquiesce_queue() if it is | |
2222 | * quiesced. | |
2223 | */ | |
41adf531 | 2224 | __blk_mq_run_dispatch_ops(hctx->queue, false, |
2a904d00 ML |
2225 | need_run = !blk_queue_quiesced(hctx->queue) && |
2226 | blk_mq_hctx_has_pending(hctx)); | |
24f5a90f | 2227 | |
1aa8d875 CH |
2228 | if (!need_run) |
2229 | return; | |
2230 | ||
2231 | if (async || (hctx->flags & BLK_MQ_F_BLOCKING) || | |
2232 | !cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)) { | |
2233 | blk_mq_delay_run_hw_queue(hctx, 0); | |
2234 | return; | |
2235 | } | |
2236 | ||
4d5bba5b CH |
2237 | blk_mq_run_dispatch_ops(hctx->queue, |
2238 | blk_mq_sched_dispatch_requests(hctx)); | |
320ae51f | 2239 | } |
5b727272 | 2240 | EXPORT_SYMBOL(blk_mq_run_hw_queue); |
320ae51f | 2241 | |
b6e68ee8 JK |
2242 | /* |
2243 | * Return prefered queue to dispatch from (if any) for non-mq aware IO | |
2244 | * scheduler. | |
2245 | */ | |
2246 | static struct blk_mq_hw_ctx *blk_mq_get_sq_hctx(struct request_queue *q) | |
2247 | { | |
5d05426e | 2248 | struct blk_mq_ctx *ctx = blk_mq_get_ctx(q); |
b6e68ee8 JK |
2249 | /* |
2250 | * If the IO scheduler does not respect hardware queues when | |
2251 | * dispatching, we just don't bother with multiple HW queues and | |
2252 | * dispatch from hctx for the current CPU since running multiple queues | |
2253 | * just causes lock contention inside the scheduler and pointless cache | |
2254 | * bouncing. | |
2255 | */ | |
51ab80f0 | 2256 | struct blk_mq_hw_ctx *hctx = ctx->hctxs[HCTX_TYPE_DEFAULT]; |
5d05426e | 2257 | |
b6e68ee8 JK |
2258 | if (!blk_mq_hctx_stopped(hctx)) |
2259 | return hctx; | |
2260 | return NULL; | |
2261 | } | |
2262 | ||
105663f7 | 2263 | /** |
24f7bb88 | 2264 | * blk_mq_run_hw_queues - Run all hardware queues in a request queue. |
105663f7 AA |
2265 | * @q: Pointer to the request queue to run. |
2266 | * @async: If we want to run the queue asynchronously. | |
2267 | */ | |
b94ec296 | 2268 | void blk_mq_run_hw_queues(struct request_queue *q, bool async) |
320ae51f | 2269 | { |
b6e68ee8 | 2270 | struct blk_mq_hw_ctx *hctx, *sq_hctx; |
4f481208 | 2271 | unsigned long i; |
320ae51f | 2272 | |
b6e68ee8 | 2273 | sq_hctx = NULL; |
4d337ceb | 2274 | if (blk_queue_sq_sched(q)) |
b6e68ee8 | 2275 | sq_hctx = blk_mq_get_sq_hctx(q); |
320ae51f | 2276 | queue_for_each_hw_ctx(q, hctx, i) { |
79f720a7 | 2277 | if (blk_mq_hctx_stopped(hctx)) |
320ae51f | 2278 | continue; |
b6e68ee8 JK |
2279 | /* |
2280 | * Dispatch from this hctx either if there's no hctx preferred | |
2281 | * by IO scheduler or if it has requests that bypass the | |
2282 | * scheduler. | |
2283 | */ | |
2284 | if (!sq_hctx || sq_hctx == hctx || | |
2285 | !list_empty_careful(&hctx->dispatch)) | |
2286 | blk_mq_run_hw_queue(hctx, async); | |
320ae51f JA |
2287 | } |
2288 | } | |
b94ec296 | 2289 | EXPORT_SYMBOL(blk_mq_run_hw_queues); |
320ae51f | 2290 | |
b9151e7b DA |
2291 | /** |
2292 | * blk_mq_delay_run_hw_queues - Run all hardware queues asynchronously. | |
2293 | * @q: Pointer to the request queue to run. | |
fa94ba8a | 2294 | * @msecs: Milliseconds of delay to wait before running the queues. |
b9151e7b DA |
2295 | */ |
2296 | void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs) | |
2297 | { | |
b6e68ee8 | 2298 | struct blk_mq_hw_ctx *hctx, *sq_hctx; |
4f481208 | 2299 | unsigned long i; |
b9151e7b | 2300 | |
b6e68ee8 | 2301 | sq_hctx = NULL; |
4d337ceb | 2302 | if (blk_queue_sq_sched(q)) |
b6e68ee8 | 2303 | sq_hctx = blk_mq_get_sq_hctx(q); |
b9151e7b DA |
2304 | queue_for_each_hw_ctx(q, hctx, i) { |
2305 | if (blk_mq_hctx_stopped(hctx)) | |
2306 | continue; | |
8f5fea65 DJ |
2307 | /* |
2308 | * If there is already a run_work pending, leave the | |
2309 | * pending delay untouched. Otherwise, a hctx can stall | |
2310 | * if another hctx is re-delaying the other's work | |
2311 | * before the work executes. | |
2312 | */ | |
2313 | if (delayed_work_pending(&hctx->run_work)) | |
2314 | continue; | |
b6e68ee8 JK |
2315 | /* |
2316 | * Dispatch from this hctx either if there's no hctx preferred | |
2317 | * by IO scheduler or if it has requests that bypass the | |
2318 | * scheduler. | |
2319 | */ | |
2320 | if (!sq_hctx || sq_hctx == hctx || | |
2321 | !list_empty_careful(&hctx->dispatch)) | |
2322 | blk_mq_delay_run_hw_queue(hctx, msecs); | |
b9151e7b DA |
2323 | } |
2324 | } | |
2325 | EXPORT_SYMBOL(blk_mq_delay_run_hw_queues); | |
2326 | ||
39a70c76 ML |
2327 | /* |
2328 | * This function is often used for pausing .queue_rq() by driver when | |
2329 | * there isn't enough resource or some conditions aren't satisfied, and | |
4d606219 | 2330 | * BLK_STS_RESOURCE is usually returned. |
39a70c76 ML |
2331 | * |
2332 | * We do not guarantee that dispatch can be drained or blocked | |
2333 | * after blk_mq_stop_hw_queue() returns. Please use | |
2334 | * blk_mq_quiesce_queue() for that requirement. | |
2335 | */ | |
2719aa21 JA |
2336 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) |
2337 | { | |
641a9ed6 | 2338 | cancel_delayed_work(&hctx->run_work); |
280d45f6 | 2339 | |
641a9ed6 | 2340 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
2719aa21 | 2341 | } |
641a9ed6 | 2342 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); |
2719aa21 | 2343 | |
39a70c76 ML |
2344 | /* |
2345 | * This function is often used for pausing .queue_rq() by driver when | |
2346 | * there isn't enough resource or some conditions aren't satisfied, and | |
4d606219 | 2347 | * BLK_STS_RESOURCE is usually returned. |
39a70c76 ML |
2348 | * |
2349 | * We do not guarantee that dispatch can be drained or blocked | |
2350 | * after blk_mq_stop_hw_queues() returns. Please use | |
2351 | * blk_mq_quiesce_queue() for that requirement. | |
2352 | */ | |
2719aa21 JA |
2353 | void blk_mq_stop_hw_queues(struct request_queue *q) |
2354 | { | |
641a9ed6 | 2355 | struct blk_mq_hw_ctx *hctx; |
4f481208 | 2356 | unsigned long i; |
641a9ed6 ML |
2357 | |
2358 | queue_for_each_hw_ctx(q, hctx, i) | |
2359 | blk_mq_stop_hw_queue(hctx); | |
280d45f6 CH |
2360 | } |
2361 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
2362 | ||
320ae51f JA |
2363 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
2364 | { | |
2365 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 2366 | |
0ffbce80 | 2367 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
2368 | } |
2369 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
2370 | ||
2f268556 CH |
2371 | void blk_mq_start_hw_queues(struct request_queue *q) |
2372 | { | |
2373 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 2374 | unsigned long i; |
2f268556 CH |
2375 | |
2376 | queue_for_each_hw_ctx(q, hctx, i) | |
2377 | blk_mq_start_hw_queue(hctx); | |
2378 | } | |
2379 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
2380 | ||
ae911c5e JA |
2381 | void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
2382 | { | |
2383 | if (!blk_mq_hctx_stopped(hctx)) | |
2384 | return; | |
2385 | ||
2386 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
2387 | blk_mq_run_hw_queue(hctx, async); | |
2388 | } | |
2389 | EXPORT_SYMBOL_GPL(blk_mq_start_stopped_hw_queue); | |
2390 | ||
1b4a3258 | 2391 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
2392 | { |
2393 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 2394 | unsigned long i; |
320ae51f | 2395 | |
ae911c5e JA |
2396 | queue_for_each_hw_ctx(q, hctx, i) |
2397 | blk_mq_start_stopped_hw_queue(hctx, async); | |
320ae51f JA |
2398 | } |
2399 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
2400 | ||
70f4db63 | 2401 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f | 2402 | { |
c20a1a2c CH |
2403 | struct blk_mq_hw_ctx *hctx = |
2404 | container_of(work, struct blk_mq_hw_ctx, run_work.work); | |
7b607814 | 2405 | |
4d5bba5b CH |
2406 | blk_mq_run_dispatch_ops(hctx->queue, |
2407 | blk_mq_sched_dispatch_requests(hctx)); | |
320ae51f JA |
2408 | } |
2409 | ||
105663f7 AA |
2410 | /** |
2411 | * blk_mq_request_bypass_insert - Insert a request at dispatch list. | |
2412 | * @rq: Pointer to request to be inserted. | |
2b597613 | 2413 | * @flags: BLK_MQ_INSERT_* |
105663f7 | 2414 | * |
157f377b JA |
2415 | * Should only be used carefully, when the caller knows we want to |
2416 | * bypass a potential IO scheduler on the target device. | |
2417 | */ | |
360f2648 | 2418 | static void blk_mq_request_bypass_insert(struct request *rq, blk_insert_t flags) |
157f377b | 2419 | { |
ea4f995e | 2420 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
157f377b JA |
2421 | |
2422 | spin_lock(&hctx->lock); | |
2b597613 | 2423 | if (flags & BLK_MQ_INSERT_AT_HEAD) |
01e99aec ML |
2424 | list_add(&rq->queuelist, &hctx->dispatch); |
2425 | else | |
2426 | list_add_tail(&rq->queuelist, &hctx->dispatch); | |
157f377b | 2427 | spin_unlock(&hctx->lock); |
157f377b JA |
2428 | } |
2429 | ||
05a93117 CH |
2430 | static void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, |
2431 | struct blk_mq_ctx *ctx, struct list_head *list, | |
2432 | bool run_queue_async) | |
320ae51f | 2433 | { |
3f0cedc7 | 2434 | struct request *rq; |
c16d6b5a | 2435 | enum hctx_type type = hctx->type; |
3f0cedc7 | 2436 | |
94aa228c CH |
2437 | /* |
2438 | * Try to issue requests directly if the hw queue isn't busy to save an | |
2439 | * extra enqueue & dequeue to the sw queue. | |
2440 | */ | |
2441 | if (!hctx->dispatch_busy && !run_queue_async) { | |
2442 | blk_mq_run_dispatch_ops(hctx->queue, | |
2443 | blk_mq_try_issue_list_directly(hctx, list)); | |
2444 | if (list_empty(list)) | |
2445 | goto out; | |
2446 | } | |
2447 | ||
320ae51f JA |
2448 | /* |
2449 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
2450 | * offline now | |
2451 | */ | |
3f0cedc7 | 2452 | list_for_each_entry(rq, list, queuelist) { |
e57690fe | 2453 | BUG_ON(rq->mq_ctx != ctx); |
a54895fa | 2454 | trace_block_rq_insert(rq); |
320ae51f | 2455 | } |
3f0cedc7 ML |
2456 | |
2457 | spin_lock(&ctx->lock); | |
c16d6b5a | 2458 | list_splice_tail_init(list, &ctx->rq_lists[type]); |
cfd0c552 | 2459 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f | 2460 | spin_unlock(&ctx->lock); |
94aa228c CH |
2461 | out: |
2462 | blk_mq_run_hw_queue(hctx, run_queue_async); | |
320ae51f JA |
2463 | } |
2464 | ||
710fa378 | 2465 | static void blk_mq_insert_request(struct request *rq, blk_insert_t flags) |
2bd215df CH |
2466 | { |
2467 | struct request_queue *q = rq->q; | |
2bd215df CH |
2468 | struct blk_mq_ctx *ctx = rq->mq_ctx; |
2469 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; | |
2470 | ||
53548d2a CH |
2471 | if (blk_rq_is_passthrough(rq)) { |
2472 | /* | |
2473 | * Passthrough request have to be added to hctx->dispatch | |
2474 | * directly. The device may be in a situation where it can't | |
2475 | * handle FS request, and always returns BLK_STS_RESOURCE for | |
2476 | * them, which gets them added to hctx->dispatch. | |
2477 | * | |
2478 | * If a passthrough request is required to unblock the queues, | |
2479 | * and it is added to the scheduler queue, there is no chance to | |
2480 | * dispatch it given we prioritize requests in hctx->dispatch. | |
2481 | */ | |
2b597613 | 2482 | blk_mq_request_bypass_insert(rq, flags); |
be4c4278 | 2483 | } else if (req_op(rq) == REQ_OP_FLUSH) { |
2bd215df CH |
2484 | /* |
2485 | * Firstly normal IO request is inserted to scheduler queue or | |
2486 | * sw queue, meantime we add flush request to dispatch queue( | |
2487 | * hctx->dispatch) directly and there is at most one in-flight | |
2488 | * flush request for each hw queue, so it doesn't matter to add | |
2489 | * flush request to tail or front of the dispatch queue. | |
2490 | * | |
2491 | * Secondly in case of NCQ, flush request belongs to non-NCQ | |
2492 | * command, and queueing it will fail when there is any | |
2493 | * in-flight normal IO request(NCQ command). When adding flush | |
2494 | * rq to the front of hctx->dispatch, it is easier to introduce | |
2495 | * extra time to flush rq's latency because of S_SCHED_RESTART | |
2496 | * compared with adding to the tail of dispatch queue, then | |
2497 | * chance of flush merge is increased, and less flush requests | |
2498 | * will be issued to controller. It is observed that ~10% time | |
2499 | * is saved in blktests block/004 on disk attached to AHCI/NCQ | |
2500 | * drive when adding flush rq to the front of hctx->dispatch. | |
2501 | * | |
2502 | * Simply queue flush rq to the front of hctx->dispatch so that | |
2503 | * intensive flush workloads can benefit in case of NCQ HW. | |
2504 | */ | |
2b597613 | 2505 | blk_mq_request_bypass_insert(rq, BLK_MQ_INSERT_AT_HEAD); |
53548d2a | 2506 | } else if (q->elevator) { |
2bd215df CH |
2507 | LIST_HEAD(list); |
2508 | ||
53548d2a CH |
2509 | WARN_ON_ONCE(rq->tag != BLK_MQ_NO_TAG); |
2510 | ||
2bd215df | 2511 | list_add(&rq->queuelist, &list); |
93fffe16 | 2512 | q->elevator->type->ops.insert_requests(hctx, &list, flags); |
2bd215df | 2513 | } else { |
4ec5c055 CH |
2514 | trace_block_rq_insert(rq); |
2515 | ||
2bd215df | 2516 | spin_lock(&ctx->lock); |
710fa378 | 2517 | if (flags & BLK_MQ_INSERT_AT_HEAD) |
4ec5c055 CH |
2518 | list_add(&rq->queuelist, &ctx->rq_lists[hctx->type]); |
2519 | else | |
2520 | list_add_tail(&rq->queuelist, | |
2521 | &ctx->rq_lists[hctx->type]); | |
a88db1e0 | 2522 | blk_mq_hctx_mark_pending(hctx, ctx); |
2bd215df CH |
2523 | spin_unlock(&ctx->lock); |
2524 | } | |
320ae51f JA |
2525 | } |
2526 | ||
14ccb66b CH |
2527 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio, |
2528 | unsigned int nr_segs) | |
320ae51f | 2529 | { |
93f221ae EB |
2530 | int err; |
2531 | ||
f924cdde CH |
2532 | if (bio->bi_opf & REQ_RAHEAD) |
2533 | rq->cmd_flags |= REQ_FAILFAST_MASK; | |
2534 | ||
2535 | rq->__sector = bio->bi_iter.bi_sector; | |
14ccb66b | 2536 | blk_rq_bio_prep(rq, bio, nr_segs); |
93f221ae EB |
2537 | |
2538 | /* This can't fail, since GFP_NOIO includes __GFP_DIRECT_RECLAIM. */ | |
2539 | err = blk_crypto_rq_bio_prep(rq, bio, GFP_NOIO); | |
2540 | WARN_ON_ONCE(err); | |
4b570521 | 2541 | |
b5af37ab | 2542 | blk_account_io_start(rq); |
320ae51f JA |
2543 | } |
2544 | ||
0f95549c | 2545 | static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx, |
3e08773c | 2546 | struct request *rq, bool last) |
f984df1f | 2547 | { |
f984df1f | 2548 | struct request_queue *q = rq->q; |
f984df1f SL |
2549 | struct blk_mq_queue_data bd = { |
2550 | .rq = rq, | |
be94f058 | 2551 | .last = last, |
f984df1f | 2552 | }; |
f06345ad | 2553 | blk_status_t ret; |
0f95549c | 2554 | |
0f95549c MS |
2555 | /* |
2556 | * For OK queue, we are done. For error, caller may kill it. | |
2557 | * Any other error (busy), just add it to our list as we | |
2558 | * previously would have done. | |
2559 | */ | |
2560 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
2561 | switch (ret) { | |
2562 | case BLK_STS_OK: | |
6ce3dd6e | 2563 | blk_mq_update_dispatch_busy(hctx, false); |
0f95549c MS |
2564 | break; |
2565 | case BLK_STS_RESOURCE: | |
86ff7c2a | 2566 | case BLK_STS_DEV_RESOURCE: |
6ce3dd6e | 2567 | blk_mq_update_dispatch_busy(hctx, true); |
0f95549c MS |
2568 | __blk_mq_requeue_request(rq); |
2569 | break; | |
2570 | default: | |
6ce3dd6e | 2571 | blk_mq_update_dispatch_busy(hctx, false); |
0f95549c MS |
2572 | break; |
2573 | } | |
2574 | ||
2575 | return ret; | |
2576 | } | |
2577 | ||
2b71b877 | 2578 | static bool blk_mq_get_budget_and_tag(struct request *rq) |
0f95549c | 2579 | { |
2a5a24aa | 2580 | int budget_token; |
d964f04a | 2581 | |
2b71b877 | 2582 | budget_token = blk_mq_get_dispatch_budget(rq->q); |
2a5a24aa | 2583 | if (budget_token < 0) |
2b71b877 | 2584 | return false; |
2a5a24aa | 2585 | blk_mq_set_rq_budget_token(rq, budget_token); |
8ab6bb9e | 2586 | if (!blk_mq_get_driver_tag(rq)) { |
2b71b877 CH |
2587 | blk_mq_put_dispatch_budget(rq->q, budget_token); |
2588 | return false; | |
88022d72 | 2589 | } |
2b71b877 | 2590 | return true; |
fd9c40f6 BVA |
2591 | } |
2592 | ||
105663f7 AA |
2593 | /** |
2594 | * blk_mq_try_issue_directly - Try to send a request directly to device driver. | |
2595 | * @hctx: Pointer of the associated hardware queue. | |
2596 | * @rq: Pointer to request to be sent. | |
105663f7 AA |
2597 | * |
2598 | * If the device has enough resources to accept a new request now, send the | |
2599 | * request directly to device driver. Else, insert at hctx->dispatch queue, so | |
2600 | * we can try send it another time in the future. Requests inserted at this | |
2601 | * queue have higher priority. | |
2602 | */ | |
fd9c40f6 | 2603 | static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, |
3e08773c | 2604 | struct request *rq) |
fd9c40f6 | 2605 | { |
e1f44ac0 CH |
2606 | blk_status_t ret; |
2607 | ||
2608 | if (blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(rq->q)) { | |
710fa378 | 2609 | blk_mq_insert_request(rq, 0); |
e1f44ac0 CH |
2610 | return; |
2611 | } | |
2612 | ||
dd6216bb | 2613 | if ((rq->rq_flags & RQF_USE_SCHED) || !blk_mq_get_budget_and_tag(rq)) { |
710fa378 | 2614 | blk_mq_insert_request(rq, 0); |
f0dbe6e8 | 2615 | blk_mq_run_hw_queue(hctx, false); |
e1f44ac0 CH |
2616 | return; |
2617 | } | |
fd9c40f6 | 2618 | |
e1f44ac0 CH |
2619 | ret = __blk_mq_issue_directly(hctx, rq, true); |
2620 | switch (ret) { | |
2621 | case BLK_STS_OK: | |
2622 | break; | |
2623 | case BLK_STS_RESOURCE: | |
2624 | case BLK_STS_DEV_RESOURCE: | |
2b597613 | 2625 | blk_mq_request_bypass_insert(rq, 0); |
2394395c | 2626 | blk_mq_run_hw_queue(hctx, false); |
e1f44ac0 CH |
2627 | break; |
2628 | default: | |
fd9c40f6 | 2629 | blk_mq_end_request(rq, ret); |
e1f44ac0 CH |
2630 | break; |
2631 | } | |
fd9c40f6 BVA |
2632 | } |
2633 | ||
06c8c691 | 2634 | static blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last) |
fd9c40f6 | 2635 | { |
e1f44ac0 CH |
2636 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
2637 | ||
2638 | if (blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(rq->q)) { | |
710fa378 | 2639 | blk_mq_insert_request(rq, 0); |
e1f44ac0 CH |
2640 | return BLK_STS_OK; |
2641 | } | |
2642 | ||
2643 | if (!blk_mq_get_budget_and_tag(rq)) | |
2644 | return BLK_STS_RESOURCE; | |
2645 | return __blk_mq_issue_directly(hctx, rq, last); | |
5eb6126e CH |
2646 | } |
2647 | ||
3e368fb0 | 2648 | static void blk_mq_plug_issue_direct(struct blk_plug *plug) |
b84c5b50 CH |
2649 | { |
2650 | struct blk_mq_hw_ctx *hctx = NULL; | |
2651 | struct request *rq; | |
2652 | int queued = 0; | |
0d617a83 | 2653 | blk_status_t ret = BLK_STS_OK; |
b84c5b50 CH |
2654 | |
2655 | while ((rq = rq_list_pop(&plug->mq_list))) { | |
2656 | bool last = rq_list_empty(plug->mq_list); | |
b84c5b50 CH |
2657 | |
2658 | if (hctx != rq->mq_hctx) { | |
34c9f547 KS |
2659 | if (hctx) { |
2660 | blk_mq_commit_rqs(hctx, queued, false); | |
2661 | queued = 0; | |
2662 | } | |
b84c5b50 CH |
2663 | hctx = rq->mq_hctx; |
2664 | } | |
2665 | ||
2666 | ret = blk_mq_request_issue_directly(rq, last); | |
2667 | switch (ret) { | |
2668 | case BLK_STS_OK: | |
2669 | queued++; | |
2670 | break; | |
2671 | case BLK_STS_RESOURCE: | |
2672 | case BLK_STS_DEV_RESOURCE: | |
2b597613 | 2673 | blk_mq_request_bypass_insert(rq, 0); |
2394395c | 2674 | blk_mq_run_hw_queue(hctx, false); |
0d617a83 | 2675 | goto out; |
b84c5b50 CH |
2676 | default: |
2677 | blk_mq_end_request(rq, ret); | |
b84c5b50 CH |
2678 | break; |
2679 | } | |
2680 | } | |
2681 | ||
0d617a83 KS |
2682 | out: |
2683 | if (ret != BLK_STS_OK) | |
34c9f547 | 2684 | blk_mq_commit_rqs(hctx, queued, false); |
b84c5b50 CH |
2685 | } |
2686 | ||
518579a9 KB |
2687 | static void __blk_mq_flush_plug_list(struct request_queue *q, |
2688 | struct blk_plug *plug) | |
2689 | { | |
2690 | if (blk_queue_quiesced(q)) | |
2691 | return; | |
2692 | q->mq_ops->queue_rqs(&plug->mq_list); | |
2693 | } | |
2694 | ||
26fed4ac JA |
2695 | static void blk_mq_dispatch_plug_list(struct blk_plug *plug, bool from_sched) |
2696 | { | |
2697 | struct blk_mq_hw_ctx *this_hctx = NULL; | |
2698 | struct blk_mq_ctx *this_ctx = NULL; | |
2699 | struct request *requeue_list = NULL; | |
34e0a279 | 2700 | struct request **requeue_lastp = &requeue_list; |
26fed4ac | 2701 | unsigned int depth = 0; |
d97217e7 | 2702 | bool is_passthrough = false; |
26fed4ac JA |
2703 | LIST_HEAD(list); |
2704 | ||
2705 | do { | |
2706 | struct request *rq = rq_list_pop(&plug->mq_list); | |
2707 | ||
2708 | if (!this_hctx) { | |
2709 | this_hctx = rq->mq_hctx; | |
2710 | this_ctx = rq->mq_ctx; | |
d97217e7 ML |
2711 | is_passthrough = blk_rq_is_passthrough(rq); |
2712 | } else if (this_hctx != rq->mq_hctx || this_ctx != rq->mq_ctx || | |
2713 | is_passthrough != blk_rq_is_passthrough(rq)) { | |
34e0a279 | 2714 | rq_list_add_tail(&requeue_lastp, rq); |
26fed4ac JA |
2715 | continue; |
2716 | } | |
34e0a279 | 2717 | list_add(&rq->queuelist, &list); |
26fed4ac JA |
2718 | depth++; |
2719 | } while (!rq_list_empty(plug->mq_list)); | |
2720 | ||
2721 | plug->mq_list = requeue_list; | |
2722 | trace_block_unplug(this_hctx->queue, depth, !from_sched); | |
05a93117 CH |
2723 | |
2724 | percpu_ref_get(&this_hctx->queue->q_usage_counter); | |
d97217e7 | 2725 | /* passthrough requests should never be issued to the I/O scheduler */ |
2293cae7 ML |
2726 | if (is_passthrough) { |
2727 | spin_lock(&this_hctx->lock); | |
2728 | list_splice_tail_init(&list, &this_hctx->dispatch); | |
2729 | spin_unlock(&this_hctx->lock); | |
2730 | blk_mq_run_hw_queue(this_hctx, from_sched); | |
2731 | } else if (this_hctx->queue->elevator) { | |
05a93117 | 2732 | this_hctx->queue->elevator->type->ops.insert_requests(this_hctx, |
93fffe16 | 2733 | &list, 0); |
05a93117 CH |
2734 | blk_mq_run_hw_queue(this_hctx, from_sched); |
2735 | } else { | |
2736 | blk_mq_insert_requests(this_hctx, this_ctx, &list, from_sched); | |
2737 | } | |
2738 | percpu_ref_put(&this_hctx->queue->q_usage_counter); | |
26fed4ac JA |
2739 | } |
2740 | ||
b84c5b50 CH |
2741 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) |
2742 | { | |
3c67d44d | 2743 | struct request *rq; |
b84c5b50 CH |
2744 | |
2745 | if (rq_list_empty(plug->mq_list)) | |
2746 | return; | |
2747 | plug->rq_count = 0; | |
2748 | ||
2749 | if (!plug->multiple_queues && !plug->has_elevator && !from_schedule) { | |
3c67d44d JA |
2750 | struct request_queue *q; |
2751 | ||
2752 | rq = rq_list_peek(&plug->mq_list); | |
2753 | q = rq->q; | |
2754 | ||
2755 | /* | |
2756 | * Peek first request and see if we have a ->queue_rqs() hook. | |
2757 | * If we do, we can dispatch the whole plug list in one go. We | |
2758 | * already know at this point that all requests belong to the | |
2759 | * same queue, caller must ensure that's the case. | |
2760 | * | |
2761 | * Since we pass off the full list to the driver at this point, | |
2762 | * we do not increment the active request count for the queue. | |
2763 | * Bypass shared tags for now because of that. | |
2764 | */ | |
2765 | if (q->mq_ops->queue_rqs && | |
2766 | !(rq->mq_hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) { | |
2767 | blk_mq_run_dispatch_ops(q, | |
518579a9 | 2768 | __blk_mq_flush_plug_list(q, plug)); |
3c67d44d JA |
2769 | if (rq_list_empty(plug->mq_list)) |
2770 | return; | |
2771 | } | |
73f3760e ML |
2772 | |
2773 | blk_mq_run_dispatch_ops(q, | |
3e368fb0 | 2774 | blk_mq_plug_issue_direct(plug)); |
b84c5b50 CH |
2775 | if (rq_list_empty(plug->mq_list)) |
2776 | return; | |
2777 | } | |
2778 | ||
b84c5b50 | 2779 | do { |
26fed4ac | 2780 | blk_mq_dispatch_plug_list(plug, from_schedule); |
b84c5b50 | 2781 | } while (!rq_list_empty(plug->mq_list)); |
b84c5b50 CH |
2782 | } |
2783 | ||
94aa228c | 2784 | static void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, |
6ce3dd6e ML |
2785 | struct list_head *list) |
2786 | { | |
536167d4 | 2787 | int queued = 0; |
984ce0a7 | 2788 | blk_status_t ret = BLK_STS_OK; |
536167d4 | 2789 | |
6ce3dd6e | 2790 | while (!list_empty(list)) { |
6ce3dd6e ML |
2791 | struct request *rq = list_first_entry(list, struct request, |
2792 | queuelist); | |
2793 | ||
2794 | list_del_init(&rq->queuelist); | |
fd9c40f6 | 2795 | ret = blk_mq_request_issue_directly(rq, list_empty(list)); |
27e8b2bb KS |
2796 | switch (ret) { |
2797 | case BLK_STS_OK: | |
536167d4 | 2798 | queued++; |
27e8b2bb KS |
2799 | break; |
2800 | case BLK_STS_RESOURCE: | |
2801 | case BLK_STS_DEV_RESOURCE: | |
2b597613 | 2802 | blk_mq_request_bypass_insert(rq, 0); |
2394395c CH |
2803 | if (list_empty(list)) |
2804 | blk_mq_run_hw_queue(hctx, false); | |
27e8b2bb KS |
2805 | goto out; |
2806 | default: | |
2807 | blk_mq_end_request(rq, ret); | |
2808 | break; | |
2809 | } | |
6ce3dd6e | 2810 | } |
d666ba98 | 2811 | |
27e8b2bb | 2812 | out: |
984ce0a7 KS |
2813 | if (ret != BLK_STS_OK) |
2814 | blk_mq_commit_rqs(hctx, queued, false); | |
6ce3dd6e ML |
2815 | } |
2816 | ||
b131f201 | 2817 | static bool blk_mq_attempt_bio_merge(struct request_queue *q, |
0c5bcc92 | 2818 | struct bio *bio, unsigned int nr_segs) |
900e0807 JA |
2819 | { |
2820 | if (!blk_queue_nomerges(q) && bio_mergeable(bio)) { | |
0c5bcc92 | 2821 | if (blk_attempt_plug_merge(q, bio, nr_segs)) |
900e0807 JA |
2822 | return true; |
2823 | if (blk_mq_sched_bio_merge(q, bio, nr_segs)) | |
2824 | return true; | |
2825 | } | |
2826 | return false; | |
2827 | } | |
2828 | ||
71539717 JA |
2829 | static struct request *blk_mq_get_new_requests(struct request_queue *q, |
2830 | struct blk_plug *plug, | |
0a5aa8d1 SK |
2831 | struct bio *bio, |
2832 | unsigned int nsegs) | |
71539717 JA |
2833 | { |
2834 | struct blk_mq_alloc_data data = { | |
2835 | .q = q, | |
2836 | .nr_tags = 1, | |
9d497e29 | 2837 | .cmd_flags = bio->bi_opf, |
71539717 JA |
2838 | }; |
2839 | struct request *rq; | |
2840 | ||
5b13bc8a | 2841 | if (unlikely(bio_queue_enter(bio))) |
b637108a | 2842 | return NULL; |
900e0807 | 2843 | |
0a5aa8d1 SK |
2844 | if (blk_mq_attempt_bio_merge(q, bio, nsegs)) |
2845 | goto queue_exit; | |
2846 | ||
2847 | rq_qos_throttle(q, bio); | |
2848 | ||
71539717 JA |
2849 | if (plug) { |
2850 | data.nr_tags = plug->nr_ios; | |
2851 | plug->nr_ios = 1; | |
2852 | data.cached_rq = &plug->cached_rq; | |
2853 | } | |
2854 | ||
2855 | rq = __blk_mq_alloc_requests(&data); | |
373b5416 JA |
2856 | if (rq) |
2857 | return rq; | |
71539717 JA |
2858 | rq_qos_cleanup(q, bio); |
2859 | if (bio->bi_opf & REQ_NOWAIT) | |
2860 | bio_wouldblock_error(bio); | |
0a5aa8d1 | 2861 | queue_exit: |
5b13bc8a | 2862 | blk_queue_exit(q); |
71539717 JA |
2863 | return NULL; |
2864 | } | |
2865 | ||
5b13bc8a | 2866 | static inline struct request *blk_mq_get_cached_request(struct request_queue *q, |
0a5aa8d1 | 2867 | struct blk_plug *plug, struct bio **bio, unsigned int nsegs) |
71539717 | 2868 | { |
b637108a | 2869 | struct request *rq; |
77465647 | 2870 | enum hctx_type type, hctx_type; |
b637108a | 2871 | |
5b13bc8a CH |
2872 | if (!plug) |
2873 | return NULL; | |
81ea1222 ML |
2874 | rq = rq_list_peek(&plug->cached_rq); |
2875 | if (!rq || rq->q != q) | |
2876 | return NULL; | |
71539717 | 2877 | |
0a5aa8d1 SK |
2878 | if (blk_mq_attempt_bio_merge(q, *bio, nsegs)) { |
2879 | *bio = NULL; | |
2880 | return NULL; | |
2881 | } | |
2882 | ||
77465647 PB |
2883 | type = blk_mq_get_hctx_type((*bio)->bi_opf); |
2884 | hctx_type = rq->mq_hctx->type; | |
2885 | if (type != hctx_type && | |
2886 | !(type == HCTX_TYPE_READ && hctx_type == HCTX_TYPE_DEFAULT)) | |
5b13bc8a | 2887 | return NULL; |
0a5aa8d1 | 2888 | if (op_is_flush(rq->cmd_flags) != op_is_flush((*bio)->bi_opf)) |
5b13bc8a CH |
2889 | return NULL; |
2890 | ||
2645672f JA |
2891 | /* |
2892 | * If any qos ->throttle() end up blocking, we will have flushed the | |
2893 | * plug and hence killed the cached_rq list as well. Pop this entry | |
2894 | * before we throttle. | |
2895 | */ | |
5b13bc8a | 2896 | plug->cached_rq = rq_list_next(rq); |
2645672f JA |
2897 | rq_qos_throttle(q, *bio); |
2898 | ||
2899 | rq->cmd_flags = (*bio)->bi_opf; | |
5b13bc8a | 2900 | INIT_LIST_HEAD(&rq->queuelist); |
5b13bc8a | 2901 | return rq; |
71539717 JA |
2902 | } |
2903 | ||
82b74cac JK |
2904 | static void bio_set_ioprio(struct bio *bio) |
2905 | { | |
a78418e6 JK |
2906 | /* Nobody set ioprio so far? Initialize it based on task's nice value */ |
2907 | if (IOPRIO_PRIO_CLASS(bio->bi_ioprio) == IOPRIO_CLASS_NONE) | |
2908 | bio->bi_ioprio = get_current_ioprio(); | |
82b74cac JK |
2909 | blkcg_set_ioprio(bio); |
2910 | } | |
2911 | ||
105663f7 | 2912 | /** |
c62b37d9 | 2913 | * blk_mq_submit_bio - Create and send a request to block device. |
105663f7 AA |
2914 | * @bio: Bio pointer. |
2915 | * | |
2916 | * Builds up a request structure from @q and @bio and send to the device. The | |
2917 | * request may not be queued directly to hardware if: | |
2918 | * * This request can be merged with another one | |
2919 | * * We want to place request at plug queue for possible future merging | |
2920 | * * There is an IO scheduler active at this queue | |
2921 | * | |
2922 | * It will not queue the request if there is an error with the bio, or at the | |
2923 | * request creation. | |
105663f7 | 2924 | */ |
3e08773c | 2925 | void blk_mq_submit_bio(struct bio *bio) |
07068d5b | 2926 | { |
ed6cddef | 2927 | struct request_queue *q = bdev_get_queue(bio->bi_bdev); |
6deacb3b | 2928 | struct blk_plug *plug = blk_mq_plug(bio); |
ef295ecf | 2929 | const int is_sync = op_is_sync(bio->bi_opf); |
f0dbe6e8 | 2930 | struct blk_mq_hw_ctx *hctx; |
07068d5b | 2931 | struct request *rq; |
abd45c15 | 2932 | unsigned int nr_segs = 1; |
a892c8d5 | 2933 | blk_status_t ret; |
07068d5b | 2934 | |
51d798cd | 2935 | bio = blk_queue_bounce(bio, q); |
613b1488 | 2936 | if (bio_may_exceed_limits(bio, &q->limits)) { |
c55ddd90 | 2937 | bio = __bio_split_to_limits(bio, &q->limits, &nr_segs); |
613b1488 JA |
2938 | if (!bio) |
2939 | return; | |
2940 | } | |
f36ea50c | 2941 | |
e23947bd | 2942 | if (!bio_integrity_prep(bio)) |
900e0807 | 2943 | return; |
87760e5e | 2944 | |
9c6227e0 JK |
2945 | bio_set_ioprio(bio); |
2946 | ||
0a5aa8d1 | 2947 | rq = blk_mq_get_cached_request(q, plug, &bio, nr_segs); |
5b13bc8a | 2948 | if (!rq) { |
0a5aa8d1 SK |
2949 | if (!bio) |
2950 | return; | |
2951 | rq = blk_mq_get_new_requests(q, plug, bio, nr_segs); | |
5b13bc8a CH |
2952 | if (unlikely(!rq)) |
2953 | return; | |
2954 | } | |
87760e5e | 2955 | |
e8a676d6 | 2956 | trace_block_getrq(bio); |
d6f1dda2 | 2957 | |
c1c80384 | 2958 | rq_qos_track(q, rq, bio); |
07068d5b | 2959 | |
970d168d BVA |
2960 | blk_mq_bio_to_request(rq, bio, nr_segs); |
2961 | ||
9cd1e566 | 2962 | ret = blk_crypto_rq_get_keyslot(rq); |
a892c8d5 ST |
2963 | if (ret != BLK_STS_OK) { |
2964 | bio->bi_status = ret; | |
2965 | bio_endio(bio); | |
2966 | blk_mq_free_request(rq); | |
3e08773c | 2967 | return; |
a892c8d5 ST |
2968 | } |
2969 | ||
360f2648 | 2970 | if (op_is_flush(bio->bi_opf) && blk_insert_flush(rq)) |
d92ca9d8 CH |
2971 | return; |
2972 | ||
f0dbe6e8 | 2973 | if (plug) { |
ce5b009c | 2974 | blk_add_rq_to_plug(plug, rq); |
f0dbe6e8 CH |
2975 | return; |
2976 | } | |
2977 | ||
2978 | hctx = rq->mq_hctx; | |
dd6216bb | 2979 | if ((rq->rq_flags & RQF_USE_SCHED) || |
f0dbe6e8 | 2980 | (hctx->dispatch_busy && (q->nr_hw_queues == 1 || !is_sync))) { |
710fa378 | 2981 | blk_mq_insert_request(rq, 0); |
f0dbe6e8 CH |
2982 | blk_mq_run_hw_queue(hctx, true); |
2983 | } else { | |
2984 | blk_mq_run_dispatch_ops(q, blk_mq_try_issue_directly(hctx, rq)); | |
2985 | } | |
320ae51f JA |
2986 | } |
2987 | ||
248c7933 | 2988 | #ifdef CONFIG_BLK_MQ_STACKING |
06c8c691 | 2989 | /** |
a5efda3c | 2990 | * blk_insert_cloned_request - Helper for stacking drivers to submit a request |
a5efda3c | 2991 | * @rq: the request being queued |
06c8c691 | 2992 | */ |
28db4711 | 2993 | blk_status_t blk_insert_cloned_request(struct request *rq) |
06c8c691 | 2994 | { |
28db4711 | 2995 | struct request_queue *q = rq->q; |
06c8c691 | 2996 | unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(rq)); |
49d24398 | 2997 | unsigned int max_segments = blk_rq_get_max_segments(rq); |
a5efda3c | 2998 | blk_status_t ret; |
06c8c691 CH |
2999 | |
3000 | if (blk_rq_sectors(rq) > max_sectors) { | |
3001 | /* | |
3002 | * SCSI device does not have a good way to return if | |
3003 | * Write Same/Zero is actually supported. If a device rejects | |
3004 | * a non-read/write command (discard, write same,etc.) the | |
3005 | * low-level device driver will set the relevant queue limit to | |
3006 | * 0 to prevent blk-lib from issuing more of the offending | |
3007 | * operations. Commands queued prior to the queue limit being | |
3008 | * reset need to be completed with BLK_STS_NOTSUPP to avoid I/O | |
3009 | * errors being propagated to upper layers. | |
3010 | */ | |
3011 | if (max_sectors == 0) | |
3012 | return BLK_STS_NOTSUPP; | |
3013 | ||
3014 | printk(KERN_ERR "%s: over max size limit. (%u > %u)\n", | |
3015 | __func__, blk_rq_sectors(rq), max_sectors); | |
3016 | return BLK_STS_IOERR; | |
3017 | } | |
3018 | ||
3019 | /* | |
3020 | * The queue settings related to segment counting may differ from the | |
3021 | * original queue. | |
3022 | */ | |
3023 | rq->nr_phys_segments = blk_recalc_rq_segments(rq); | |
49d24398 US |
3024 | if (rq->nr_phys_segments > max_segments) { |
3025 | printk(KERN_ERR "%s: over max segments limit. (%u > %u)\n", | |
3026 | __func__, rq->nr_phys_segments, max_segments); | |
06c8c691 CH |
3027 | return BLK_STS_IOERR; |
3028 | } | |
3029 | ||
28db4711 | 3030 | if (q->disk && should_fail_request(q->disk->part0, blk_rq_bytes(rq))) |
06c8c691 CH |
3031 | return BLK_STS_IOERR; |
3032 | ||
5b8562f0 EB |
3033 | ret = blk_crypto_rq_get_keyslot(rq); |
3034 | if (ret != BLK_STS_OK) | |
3035 | return ret; | |
06c8c691 CH |
3036 | |
3037 | blk_account_io_start(rq); | |
3038 | ||
3039 | /* | |
3040 | * Since we have a scheduler attached on the top device, | |
3041 | * bypass a potential scheduler on the bottom device for | |
3042 | * insert. | |
3043 | */ | |
28db4711 | 3044 | blk_mq_run_dispatch_ops(q, |
4cafe86c | 3045 | ret = blk_mq_request_issue_directly(rq, true)); |
592ee119 YK |
3046 | if (ret) |
3047 | blk_account_io_done(rq, ktime_get_ns()); | |
4cafe86c | 3048 | return ret; |
06c8c691 CH |
3049 | } |
3050 | EXPORT_SYMBOL_GPL(blk_insert_cloned_request); | |
3051 | ||
3052 | /** | |
3053 | * blk_rq_unprep_clone - Helper function to free all bios in a cloned request | |
3054 | * @rq: the clone request to be cleaned up | |
3055 | * | |
3056 | * Description: | |
3057 | * Free all bios in @rq for a cloned request. | |
3058 | */ | |
3059 | void blk_rq_unprep_clone(struct request *rq) | |
3060 | { | |
3061 | struct bio *bio; | |
3062 | ||
3063 | while ((bio = rq->bio) != NULL) { | |
3064 | rq->bio = bio->bi_next; | |
3065 | ||
3066 | bio_put(bio); | |
3067 | } | |
3068 | } | |
3069 | EXPORT_SYMBOL_GPL(blk_rq_unprep_clone); | |
3070 | ||
3071 | /** | |
3072 | * blk_rq_prep_clone - Helper function to setup clone request | |
3073 | * @rq: the request to be setup | |
3074 | * @rq_src: original request to be cloned | |
3075 | * @bs: bio_set that bios for clone are allocated from | |
3076 | * @gfp_mask: memory allocation mask for bio | |
3077 | * @bio_ctr: setup function to be called for each clone bio. | |
3078 | * Returns %0 for success, non %0 for failure. | |
3079 | * @data: private data to be passed to @bio_ctr | |
3080 | * | |
3081 | * Description: | |
3082 | * Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq. | |
3083 | * Also, pages which the original bios are pointing to are not copied | |
3084 | * and the cloned bios just point same pages. | |
3085 | * So cloned bios must be completed before original bios, which means | |
3086 | * the caller must complete @rq before @rq_src. | |
3087 | */ | |
3088 | int blk_rq_prep_clone(struct request *rq, struct request *rq_src, | |
3089 | struct bio_set *bs, gfp_t gfp_mask, | |
3090 | int (*bio_ctr)(struct bio *, struct bio *, void *), | |
3091 | void *data) | |
3092 | { | |
3093 | struct bio *bio, *bio_src; | |
3094 | ||
3095 | if (!bs) | |
3096 | bs = &fs_bio_set; | |
3097 | ||
3098 | __rq_for_each_bio(bio_src, rq_src) { | |
abfc426d CH |
3099 | bio = bio_alloc_clone(rq->q->disk->part0, bio_src, gfp_mask, |
3100 | bs); | |
06c8c691 CH |
3101 | if (!bio) |
3102 | goto free_and_out; | |
3103 | ||
3104 | if (bio_ctr && bio_ctr(bio, bio_src, data)) | |
3105 | goto free_and_out; | |
3106 | ||
3107 | if (rq->bio) { | |
3108 | rq->biotail->bi_next = bio; | |
3109 | rq->biotail = bio; | |
3110 | } else { | |
3111 | rq->bio = rq->biotail = bio; | |
3112 | } | |
3113 | bio = NULL; | |
3114 | } | |
3115 | ||
3116 | /* Copy attributes of the original request to the clone request. */ | |
3117 | rq->__sector = blk_rq_pos(rq_src); | |
3118 | rq->__data_len = blk_rq_bytes(rq_src); | |
3119 | if (rq_src->rq_flags & RQF_SPECIAL_PAYLOAD) { | |
3120 | rq->rq_flags |= RQF_SPECIAL_PAYLOAD; | |
3121 | rq->special_vec = rq_src->special_vec; | |
3122 | } | |
3123 | rq->nr_phys_segments = rq_src->nr_phys_segments; | |
3124 | rq->ioprio = rq_src->ioprio; | |
3125 | ||
3126 | if (rq->bio && blk_crypto_rq_bio_prep(rq, rq->bio, gfp_mask) < 0) | |
3127 | goto free_and_out; | |
3128 | ||
3129 | return 0; | |
3130 | ||
3131 | free_and_out: | |
3132 | if (bio) | |
3133 | bio_put(bio); | |
3134 | blk_rq_unprep_clone(rq); | |
3135 | ||
3136 | return -ENOMEM; | |
3137 | } | |
3138 | EXPORT_SYMBOL_GPL(blk_rq_prep_clone); | |
248c7933 | 3139 | #endif /* CONFIG_BLK_MQ_STACKING */ |
06c8c691 | 3140 | |
f2b8f3ce CH |
3141 | /* |
3142 | * Steal bios from a request and add them to a bio list. | |
3143 | * The request must not have been partially completed before. | |
3144 | */ | |
3145 | void blk_steal_bios(struct bio_list *list, struct request *rq) | |
3146 | { | |
3147 | if (rq->bio) { | |
3148 | if (list->tail) | |
3149 | list->tail->bi_next = rq->bio; | |
3150 | else | |
3151 | list->head = rq->bio; | |
3152 | list->tail = rq->biotail; | |
3153 | ||
3154 | rq->bio = NULL; | |
3155 | rq->biotail = NULL; | |
3156 | } | |
3157 | ||
3158 | rq->__data_len = 0; | |
3159 | } | |
3160 | EXPORT_SYMBOL_GPL(blk_steal_bios); | |
3161 | ||
bd63141d ML |
3162 | static size_t order_to_size(unsigned int order) |
3163 | { | |
3164 | return (size_t)PAGE_SIZE << order; | |
3165 | } | |
3166 | ||
3167 | /* called before freeing request pool in @tags */ | |
f32e4eaf JG |
3168 | static void blk_mq_clear_rq_mapping(struct blk_mq_tags *drv_tags, |
3169 | struct blk_mq_tags *tags) | |
bd63141d | 3170 | { |
bd63141d ML |
3171 | struct page *page; |
3172 | unsigned long flags; | |
3173 | ||
76dd2980 YK |
3174 | /* |
3175 | * There is no need to clear mapping if driver tags is not initialized | |
3176 | * or the mapping belongs to the driver tags. | |
3177 | */ | |
3178 | if (!drv_tags || drv_tags == tags) | |
4f245d5b JG |
3179 | return; |
3180 | ||
bd63141d ML |
3181 | list_for_each_entry(page, &tags->page_list, lru) { |
3182 | unsigned long start = (unsigned long)page_address(page); | |
3183 | unsigned long end = start + order_to_size(page->private); | |
3184 | int i; | |
3185 | ||
f32e4eaf | 3186 | for (i = 0; i < drv_tags->nr_tags; i++) { |
bd63141d ML |
3187 | struct request *rq = drv_tags->rqs[i]; |
3188 | unsigned long rq_addr = (unsigned long)rq; | |
3189 | ||
3190 | if (rq_addr >= start && rq_addr < end) { | |
0a467d0f | 3191 | WARN_ON_ONCE(req_ref_read(rq) != 0); |
bd63141d ML |
3192 | cmpxchg(&drv_tags->rqs[i], rq, NULL); |
3193 | } | |
3194 | } | |
3195 | } | |
3196 | ||
3197 | /* | |
3198 | * Wait until all pending iteration is done. | |
3199 | * | |
3200 | * Request reference is cleared and it is guaranteed to be observed | |
3201 | * after the ->lock is released. | |
3202 | */ | |
3203 | spin_lock_irqsave(&drv_tags->lock, flags); | |
3204 | spin_unlock_irqrestore(&drv_tags->lock, flags); | |
3205 | } | |
3206 | ||
cc71a6f4 JA |
3207 | void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, |
3208 | unsigned int hctx_idx) | |
95363efd | 3209 | { |
f32e4eaf | 3210 | struct blk_mq_tags *drv_tags; |
e9b267d9 | 3211 | struct page *page; |
320ae51f | 3212 | |
e02657ea ML |
3213 | if (list_empty(&tags->page_list)) |
3214 | return; | |
3215 | ||
079a2e3e JG |
3216 | if (blk_mq_is_shared_tags(set->flags)) |
3217 | drv_tags = set->shared_tags; | |
e155b0c2 JG |
3218 | else |
3219 | drv_tags = set->tags[hctx_idx]; | |
f32e4eaf | 3220 | |
65de57bb | 3221 | if (tags->static_rqs && set->ops->exit_request) { |
e9b267d9 | 3222 | int i; |
320ae51f | 3223 | |
24d2f903 | 3224 | for (i = 0; i < tags->nr_tags; i++) { |
2af8cbe3 JA |
3225 | struct request *rq = tags->static_rqs[i]; |
3226 | ||
3227 | if (!rq) | |
e9b267d9 | 3228 | continue; |
d6296d39 | 3229 | set->ops->exit_request(set, rq, hctx_idx); |
2af8cbe3 | 3230 | tags->static_rqs[i] = NULL; |
e9b267d9 | 3231 | } |
320ae51f | 3232 | } |
320ae51f | 3233 | |
f32e4eaf | 3234 | blk_mq_clear_rq_mapping(drv_tags, tags); |
bd63141d | 3235 | |
24d2f903 CH |
3236 | while (!list_empty(&tags->page_list)) { |
3237 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 3238 | list_del_init(&page->lru); |
f75782e4 CM |
3239 | /* |
3240 | * Remove kmemleak object previously allocated in | |
273938bf | 3241 | * blk_mq_alloc_rqs(). |
f75782e4 CM |
3242 | */ |
3243 | kmemleak_free(page_address(page)); | |
320ae51f JA |
3244 | __free_pages(page, page->private); |
3245 | } | |
cc71a6f4 | 3246 | } |
320ae51f | 3247 | |
e155b0c2 | 3248 | void blk_mq_free_rq_map(struct blk_mq_tags *tags) |
cc71a6f4 | 3249 | { |
24d2f903 | 3250 | kfree(tags->rqs); |
cc71a6f4 | 3251 | tags->rqs = NULL; |
2af8cbe3 JA |
3252 | kfree(tags->static_rqs); |
3253 | tags->static_rqs = NULL; | |
320ae51f | 3254 | |
e155b0c2 | 3255 | blk_mq_free_tags(tags); |
320ae51f JA |
3256 | } |
3257 | ||
4d805131 ML |
3258 | static enum hctx_type hctx_idx_to_type(struct blk_mq_tag_set *set, |
3259 | unsigned int hctx_idx) | |
3260 | { | |
3261 | int i; | |
3262 | ||
3263 | for (i = 0; i < set->nr_maps; i++) { | |
3264 | unsigned int start = set->map[i].queue_offset; | |
3265 | unsigned int end = start + set->map[i].nr_queues; | |
3266 | ||
3267 | if (hctx_idx >= start && hctx_idx < end) | |
3268 | break; | |
3269 | } | |
3270 | ||
3271 | if (i >= set->nr_maps) | |
3272 | i = HCTX_TYPE_DEFAULT; | |
3273 | ||
3274 | return i; | |
3275 | } | |
3276 | ||
3277 | static int blk_mq_get_hctx_node(struct blk_mq_tag_set *set, | |
3278 | unsigned int hctx_idx) | |
3279 | { | |
3280 | enum hctx_type type = hctx_idx_to_type(set, hctx_idx); | |
3281 | ||
3282 | return blk_mq_hw_queue_to_node(&set->map[type], hctx_idx); | |
3283 | } | |
3284 | ||
63064be1 JG |
3285 | static struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set, |
3286 | unsigned int hctx_idx, | |
3287 | unsigned int nr_tags, | |
e155b0c2 | 3288 | unsigned int reserved_tags) |
320ae51f | 3289 | { |
4d805131 | 3290 | int node = blk_mq_get_hctx_node(set, hctx_idx); |
24d2f903 | 3291 | struct blk_mq_tags *tags; |
320ae51f | 3292 | |
59f082e4 SL |
3293 | if (node == NUMA_NO_NODE) |
3294 | node = set->numa_node; | |
3295 | ||
e155b0c2 JG |
3296 | tags = blk_mq_init_tags(nr_tags, reserved_tags, node, |
3297 | BLK_MQ_FLAG_TO_ALLOC_POLICY(set->flags)); | |
24d2f903 CH |
3298 | if (!tags) |
3299 | return NULL; | |
320ae51f | 3300 | |
590b5b7d | 3301 | tags->rqs = kcalloc_node(nr_tags, sizeof(struct request *), |
36e1f3d1 | 3302 | GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, |
59f082e4 | 3303 | node); |
7edfd681 JC |
3304 | if (!tags->rqs) |
3305 | goto err_free_tags; | |
320ae51f | 3306 | |
590b5b7d KC |
3307 | tags->static_rqs = kcalloc_node(nr_tags, sizeof(struct request *), |
3308 | GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, | |
3309 | node); | |
7edfd681 JC |
3310 | if (!tags->static_rqs) |
3311 | goto err_free_rqs; | |
2af8cbe3 | 3312 | |
cc71a6f4 | 3313 | return tags; |
7edfd681 JC |
3314 | |
3315 | err_free_rqs: | |
3316 | kfree(tags->rqs); | |
3317 | err_free_tags: | |
3318 | blk_mq_free_tags(tags); | |
3319 | return NULL; | |
cc71a6f4 JA |
3320 | } |
3321 | ||
1d9bd516 TH |
3322 | static int blk_mq_init_request(struct blk_mq_tag_set *set, struct request *rq, |
3323 | unsigned int hctx_idx, int node) | |
3324 | { | |
3325 | int ret; | |
3326 | ||
3327 | if (set->ops->init_request) { | |
3328 | ret = set->ops->init_request(set, rq, hctx_idx, node); | |
3329 | if (ret) | |
3330 | return ret; | |
3331 | } | |
3332 | ||
12f5b931 | 3333 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); |
1d9bd516 TH |
3334 | return 0; |
3335 | } | |
3336 | ||
63064be1 JG |
3337 | static int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, |
3338 | struct blk_mq_tags *tags, | |
3339 | unsigned int hctx_idx, unsigned int depth) | |
cc71a6f4 JA |
3340 | { |
3341 | unsigned int i, j, entries_per_page, max_order = 4; | |
4d805131 | 3342 | int node = blk_mq_get_hctx_node(set, hctx_idx); |
cc71a6f4 | 3343 | size_t rq_size, left; |
59f082e4 | 3344 | |
59f082e4 SL |
3345 | if (node == NUMA_NO_NODE) |
3346 | node = set->numa_node; | |
cc71a6f4 JA |
3347 | |
3348 | INIT_LIST_HEAD(&tags->page_list); | |
3349 | ||
320ae51f JA |
3350 | /* |
3351 | * rq_size is the size of the request plus driver payload, rounded | |
3352 | * to the cacheline size | |
3353 | */ | |
24d2f903 | 3354 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 3355 | cache_line_size()); |
cc71a6f4 | 3356 | left = rq_size * depth; |
320ae51f | 3357 | |
cc71a6f4 | 3358 | for (i = 0; i < depth; ) { |
320ae51f JA |
3359 | int this_order = max_order; |
3360 | struct page *page; | |
3361 | int to_do; | |
3362 | void *p; | |
3363 | ||
b3a834b1 | 3364 | while (this_order && left < order_to_size(this_order - 1)) |
320ae51f JA |
3365 | this_order--; |
3366 | ||
3367 | do { | |
59f082e4 | 3368 | page = alloc_pages_node(node, |
36e1f3d1 | 3369 | GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO, |
a5164405 | 3370 | this_order); |
320ae51f JA |
3371 | if (page) |
3372 | break; | |
3373 | if (!this_order--) | |
3374 | break; | |
3375 | if (order_to_size(this_order) < rq_size) | |
3376 | break; | |
3377 | } while (1); | |
3378 | ||
3379 | if (!page) | |
24d2f903 | 3380 | goto fail; |
320ae51f JA |
3381 | |
3382 | page->private = this_order; | |
24d2f903 | 3383 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
3384 | |
3385 | p = page_address(page); | |
f75782e4 CM |
3386 | /* |
3387 | * Allow kmemleak to scan these pages as they contain pointers | |
3388 | * to additional allocations like via ops->init_request(). | |
3389 | */ | |
36e1f3d1 | 3390 | kmemleak_alloc(p, order_to_size(this_order), 1, GFP_NOIO); |
320ae51f | 3391 | entries_per_page = order_to_size(this_order) / rq_size; |
cc71a6f4 | 3392 | to_do = min(entries_per_page, depth - i); |
320ae51f JA |
3393 | left -= to_do * rq_size; |
3394 | for (j = 0; j < to_do; j++) { | |
2af8cbe3 JA |
3395 | struct request *rq = p; |
3396 | ||
3397 | tags->static_rqs[i] = rq; | |
1d9bd516 TH |
3398 | if (blk_mq_init_request(set, rq, hctx_idx, node)) { |
3399 | tags->static_rqs[i] = NULL; | |
3400 | goto fail; | |
e9b267d9 CH |
3401 | } |
3402 | ||
320ae51f JA |
3403 | p += rq_size; |
3404 | i++; | |
3405 | } | |
3406 | } | |
cc71a6f4 | 3407 | return 0; |
320ae51f | 3408 | |
24d2f903 | 3409 | fail: |
cc71a6f4 JA |
3410 | blk_mq_free_rqs(set, tags, hctx_idx); |
3411 | return -ENOMEM; | |
320ae51f JA |
3412 | } |
3413 | ||
bf0beec0 ML |
3414 | struct rq_iter_data { |
3415 | struct blk_mq_hw_ctx *hctx; | |
3416 | bool has_rq; | |
3417 | }; | |
3418 | ||
2dd6532e | 3419 | static bool blk_mq_has_request(struct request *rq, void *data) |
bf0beec0 ML |
3420 | { |
3421 | struct rq_iter_data *iter_data = data; | |
3422 | ||
3423 | if (rq->mq_hctx != iter_data->hctx) | |
3424 | return true; | |
3425 | iter_data->has_rq = true; | |
3426 | return false; | |
3427 | } | |
3428 | ||
3429 | static bool blk_mq_hctx_has_requests(struct blk_mq_hw_ctx *hctx) | |
3430 | { | |
3431 | struct blk_mq_tags *tags = hctx->sched_tags ? | |
3432 | hctx->sched_tags : hctx->tags; | |
3433 | struct rq_iter_data data = { | |
3434 | .hctx = hctx, | |
3435 | }; | |
3436 | ||
3437 | blk_mq_all_tag_iter(tags, blk_mq_has_request, &data); | |
3438 | return data.has_rq; | |
3439 | } | |
3440 | ||
3441 | static inline bool blk_mq_last_cpu_in_hctx(unsigned int cpu, | |
3442 | struct blk_mq_hw_ctx *hctx) | |
3443 | { | |
9b51d9d8 | 3444 | if (cpumask_first_and(hctx->cpumask, cpu_online_mask) != cpu) |
bf0beec0 ML |
3445 | return false; |
3446 | if (cpumask_next_and(cpu, hctx->cpumask, cpu_online_mask) < nr_cpu_ids) | |
3447 | return false; | |
3448 | return true; | |
3449 | } | |
3450 | ||
3451 | static int blk_mq_hctx_notify_offline(unsigned int cpu, struct hlist_node *node) | |
3452 | { | |
3453 | struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node, | |
3454 | struct blk_mq_hw_ctx, cpuhp_online); | |
3455 | ||
3456 | if (!cpumask_test_cpu(cpu, hctx->cpumask) || | |
3457 | !blk_mq_last_cpu_in_hctx(cpu, hctx)) | |
3458 | return 0; | |
3459 | ||
3460 | /* | |
3461 | * Prevent new request from being allocated on the current hctx. | |
3462 | * | |
3463 | * The smp_mb__after_atomic() Pairs with the implied barrier in | |
3464 | * test_and_set_bit_lock in sbitmap_get(). Ensures the inactive flag is | |
3465 | * seen once we return from the tag allocator. | |
3466 | */ | |
3467 | set_bit(BLK_MQ_S_INACTIVE, &hctx->state); | |
3468 | smp_mb__after_atomic(); | |
3469 | ||
3470 | /* | |
3471 | * Try to grab a reference to the queue and wait for any outstanding | |
3472 | * requests. If we could not grab a reference the queue has been | |
3473 | * frozen and there are no requests. | |
3474 | */ | |
3475 | if (percpu_ref_tryget(&hctx->queue->q_usage_counter)) { | |
3476 | while (blk_mq_hctx_has_requests(hctx)) | |
3477 | msleep(5); | |
3478 | percpu_ref_put(&hctx->queue->q_usage_counter); | |
3479 | } | |
3480 | ||
3481 | return 0; | |
3482 | } | |
3483 | ||
3484 | static int blk_mq_hctx_notify_online(unsigned int cpu, struct hlist_node *node) | |
3485 | { | |
3486 | struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node, | |
3487 | struct blk_mq_hw_ctx, cpuhp_online); | |
3488 | ||
3489 | if (cpumask_test_cpu(cpu, hctx->cpumask)) | |
3490 | clear_bit(BLK_MQ_S_INACTIVE, &hctx->state); | |
3491 | return 0; | |
3492 | } | |
3493 | ||
e57690fe JA |
3494 | /* |
3495 | * 'cpu' is going away. splice any existing rq_list entries from this | |
3496 | * software queue to the hw queue dispatch list, and ensure that it | |
3497 | * gets run. | |
3498 | */ | |
9467f859 | 3499 | static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) |
484b4061 | 3500 | { |
9467f859 | 3501 | struct blk_mq_hw_ctx *hctx; |
484b4061 JA |
3502 | struct blk_mq_ctx *ctx; |
3503 | LIST_HEAD(tmp); | |
c16d6b5a | 3504 | enum hctx_type type; |
484b4061 | 3505 | |
9467f859 | 3506 | hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead); |
bf0beec0 ML |
3507 | if (!cpumask_test_cpu(cpu, hctx->cpumask)) |
3508 | return 0; | |
3509 | ||
e57690fe | 3510 | ctx = __blk_mq_get_ctx(hctx->queue, cpu); |
c16d6b5a | 3511 | type = hctx->type; |
484b4061 JA |
3512 | |
3513 | spin_lock(&ctx->lock); | |
c16d6b5a ML |
3514 | if (!list_empty(&ctx->rq_lists[type])) { |
3515 | list_splice_init(&ctx->rq_lists[type], &tmp); | |
484b4061 JA |
3516 | blk_mq_hctx_clear_pending(hctx, ctx); |
3517 | } | |
3518 | spin_unlock(&ctx->lock); | |
3519 | ||
3520 | if (list_empty(&tmp)) | |
9467f859 | 3521 | return 0; |
484b4061 | 3522 | |
e57690fe JA |
3523 | spin_lock(&hctx->lock); |
3524 | list_splice_tail_init(&tmp, &hctx->dispatch); | |
3525 | spin_unlock(&hctx->lock); | |
484b4061 JA |
3526 | |
3527 | blk_mq_run_hw_queue(hctx, true); | |
9467f859 | 3528 | return 0; |
484b4061 JA |
3529 | } |
3530 | ||
9467f859 | 3531 | static void blk_mq_remove_cpuhp(struct blk_mq_hw_ctx *hctx) |
484b4061 | 3532 | { |
bf0beec0 ML |
3533 | if (!(hctx->flags & BLK_MQ_F_STACKING)) |
3534 | cpuhp_state_remove_instance_nocalls(CPUHP_AP_BLK_MQ_ONLINE, | |
3535 | &hctx->cpuhp_online); | |
9467f859 TG |
3536 | cpuhp_state_remove_instance_nocalls(CPUHP_BLK_MQ_DEAD, |
3537 | &hctx->cpuhp_dead); | |
484b4061 JA |
3538 | } |
3539 | ||
364b6181 ML |
3540 | /* |
3541 | * Before freeing hw queue, clearing the flush request reference in | |
3542 | * tags->rqs[] for avoiding potential UAF. | |
3543 | */ | |
3544 | static void blk_mq_clear_flush_rq_mapping(struct blk_mq_tags *tags, | |
3545 | unsigned int queue_depth, struct request *flush_rq) | |
3546 | { | |
3547 | int i; | |
3548 | unsigned long flags; | |
3549 | ||
3550 | /* The hw queue may not be mapped yet */ | |
3551 | if (!tags) | |
3552 | return; | |
3553 | ||
0a467d0f | 3554 | WARN_ON_ONCE(req_ref_read(flush_rq) != 0); |
364b6181 ML |
3555 | |
3556 | for (i = 0; i < queue_depth; i++) | |
3557 | cmpxchg(&tags->rqs[i], flush_rq, NULL); | |
3558 | ||
3559 | /* | |
3560 | * Wait until all pending iteration is done. | |
3561 | * | |
3562 | * Request reference is cleared and it is guaranteed to be observed | |
3563 | * after the ->lock is released. | |
3564 | */ | |
3565 | spin_lock_irqsave(&tags->lock, flags); | |
3566 | spin_unlock_irqrestore(&tags->lock, flags); | |
3567 | } | |
3568 | ||
c3b4afca | 3569 | /* hctx->ctxs will be freed in queue's release handler */ |
08e98fc6 ML |
3570 | static void blk_mq_exit_hctx(struct request_queue *q, |
3571 | struct blk_mq_tag_set *set, | |
3572 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
3573 | { | |
364b6181 ML |
3574 | struct request *flush_rq = hctx->fq->flush_rq; |
3575 | ||
8ab0b7dc ML |
3576 | if (blk_mq_hw_queue_mapped(hctx)) |
3577 | blk_mq_tag_idle(hctx); | |
08e98fc6 | 3578 | |
6cfeadbf ML |
3579 | if (blk_queue_init_done(q)) |
3580 | blk_mq_clear_flush_rq_mapping(set->tags[hctx_idx], | |
3581 | set->queue_depth, flush_rq); | |
f70ced09 | 3582 | if (set->ops->exit_request) |
364b6181 | 3583 | set->ops->exit_request(set, flush_rq, hctx_idx); |
f70ced09 | 3584 | |
08e98fc6 ML |
3585 | if (set->ops->exit_hctx) |
3586 | set->ops->exit_hctx(hctx, hctx_idx); | |
3587 | ||
9467f859 | 3588 | blk_mq_remove_cpuhp(hctx); |
2f8f1336 | 3589 | |
4e5cc99e ML |
3590 | xa_erase(&q->hctx_table, hctx_idx); |
3591 | ||
2f8f1336 ML |
3592 | spin_lock(&q->unused_hctx_lock); |
3593 | list_add(&hctx->hctx_list, &q->unused_hctx_list); | |
3594 | spin_unlock(&q->unused_hctx_lock); | |
08e98fc6 ML |
3595 | } |
3596 | ||
624dbe47 ML |
3597 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
3598 | struct blk_mq_tag_set *set, int nr_queue) | |
3599 | { | |
3600 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 3601 | unsigned long i; |
624dbe47 ML |
3602 | |
3603 | queue_for_each_hw_ctx(q, hctx, i) { | |
3604 | if (i == nr_queue) | |
3605 | break; | |
08e98fc6 | 3606 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 3607 | } |
624dbe47 ML |
3608 | } |
3609 | ||
08e98fc6 ML |
3610 | static int blk_mq_init_hctx(struct request_queue *q, |
3611 | struct blk_mq_tag_set *set, | |
3612 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 3613 | { |
7c6c5b7c ML |
3614 | hctx->queue_num = hctx_idx; |
3615 | ||
bf0beec0 ML |
3616 | if (!(hctx->flags & BLK_MQ_F_STACKING)) |
3617 | cpuhp_state_add_instance_nocalls(CPUHP_AP_BLK_MQ_ONLINE, | |
3618 | &hctx->cpuhp_online); | |
7c6c5b7c ML |
3619 | cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead); |
3620 | ||
3621 | hctx->tags = set->tags[hctx_idx]; | |
3622 | ||
3623 | if (set->ops->init_hctx && | |
3624 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
3625 | goto unregister_cpu_notifier; | |
08e98fc6 | 3626 | |
7c6c5b7c ML |
3627 | if (blk_mq_init_request(set, hctx->fq->flush_rq, hctx_idx, |
3628 | hctx->numa_node)) | |
3629 | goto exit_hctx; | |
4e5cc99e ML |
3630 | |
3631 | if (xa_insert(&q->hctx_table, hctx_idx, hctx, GFP_KERNEL)) | |
3632 | goto exit_flush_rq; | |
3633 | ||
7c6c5b7c ML |
3634 | return 0; |
3635 | ||
4e5cc99e ML |
3636 | exit_flush_rq: |
3637 | if (set->ops->exit_request) | |
3638 | set->ops->exit_request(set, hctx->fq->flush_rq, hctx_idx); | |
7c6c5b7c ML |
3639 | exit_hctx: |
3640 | if (set->ops->exit_hctx) | |
3641 | set->ops->exit_hctx(hctx, hctx_idx); | |
3642 | unregister_cpu_notifier: | |
3643 | blk_mq_remove_cpuhp(hctx); | |
3644 | return -1; | |
3645 | } | |
3646 | ||
3647 | static struct blk_mq_hw_ctx * | |
3648 | blk_mq_alloc_hctx(struct request_queue *q, struct blk_mq_tag_set *set, | |
3649 | int node) | |
3650 | { | |
3651 | struct blk_mq_hw_ctx *hctx; | |
3652 | gfp_t gfp = GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY; | |
3653 | ||
704b914f | 3654 | hctx = kzalloc_node(sizeof(struct blk_mq_hw_ctx), gfp, node); |
7c6c5b7c ML |
3655 | if (!hctx) |
3656 | goto fail_alloc_hctx; | |
3657 | ||
3658 | if (!zalloc_cpumask_var_node(&hctx->cpumask, gfp, node)) | |
3659 | goto free_hctx; | |
3660 | ||
3661 | atomic_set(&hctx->nr_active, 0); | |
08e98fc6 | 3662 | if (node == NUMA_NO_NODE) |
7c6c5b7c ML |
3663 | node = set->numa_node; |
3664 | hctx->numa_node = node; | |
08e98fc6 | 3665 | |
9f993737 | 3666 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); |
08e98fc6 ML |
3667 | spin_lock_init(&hctx->lock); |
3668 | INIT_LIST_HEAD(&hctx->dispatch); | |
3669 | hctx->queue = q; | |
51db1c37 | 3670 | hctx->flags = set->flags & ~BLK_MQ_F_TAG_QUEUE_SHARED; |
08e98fc6 | 3671 | |
2f8f1336 ML |
3672 | INIT_LIST_HEAD(&hctx->hctx_list); |
3673 | ||
320ae51f | 3674 | /* |
08e98fc6 ML |
3675 | * Allocate space for all possible cpus to avoid allocation at |
3676 | * runtime | |
320ae51f | 3677 | */ |
d904bfa7 | 3678 | hctx->ctxs = kmalloc_array_node(nr_cpu_ids, sizeof(void *), |
7c6c5b7c | 3679 | gfp, node); |
08e98fc6 | 3680 | if (!hctx->ctxs) |
7c6c5b7c | 3681 | goto free_cpumask; |
320ae51f | 3682 | |
5b202853 | 3683 | if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8), |
c548e62b | 3684 | gfp, node, false, false)) |
08e98fc6 | 3685 | goto free_ctxs; |
08e98fc6 | 3686 | hctx->nr_ctx = 0; |
320ae51f | 3687 | |
5815839b | 3688 | spin_lock_init(&hctx->dispatch_wait_lock); |
eb619fdb JA |
3689 | init_waitqueue_func_entry(&hctx->dispatch_wait, blk_mq_dispatch_wake); |
3690 | INIT_LIST_HEAD(&hctx->dispatch_wait.entry); | |
3691 | ||
754a1572 | 3692 | hctx->fq = blk_alloc_flush_queue(hctx->numa_node, set->cmd_size, gfp); |
f70ced09 | 3693 | if (!hctx->fq) |
7c6c5b7c | 3694 | goto free_bitmap; |
320ae51f | 3695 | |
7c6c5b7c | 3696 | blk_mq_hctx_kobj_init(hctx); |
6a83e74d | 3697 | |
7c6c5b7c | 3698 | return hctx; |
320ae51f | 3699 | |
08e98fc6 | 3700 | free_bitmap: |
88459642 | 3701 | sbitmap_free(&hctx->ctx_map); |
08e98fc6 ML |
3702 | free_ctxs: |
3703 | kfree(hctx->ctxs); | |
7c6c5b7c ML |
3704 | free_cpumask: |
3705 | free_cpumask_var(hctx->cpumask); | |
3706 | free_hctx: | |
3707 | kfree(hctx); | |
3708 | fail_alloc_hctx: | |
3709 | return NULL; | |
08e98fc6 | 3710 | } |
320ae51f | 3711 | |
320ae51f JA |
3712 | static void blk_mq_init_cpu_queues(struct request_queue *q, |
3713 | unsigned int nr_hw_queues) | |
3714 | { | |
b3c661b1 JA |
3715 | struct blk_mq_tag_set *set = q->tag_set; |
3716 | unsigned int i, j; | |
320ae51f JA |
3717 | |
3718 | for_each_possible_cpu(i) { | |
3719 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
3720 | struct blk_mq_hw_ctx *hctx; | |
c16d6b5a | 3721 | int k; |
320ae51f | 3722 | |
320ae51f JA |
3723 | __ctx->cpu = i; |
3724 | spin_lock_init(&__ctx->lock); | |
c16d6b5a ML |
3725 | for (k = HCTX_TYPE_DEFAULT; k < HCTX_MAX_TYPES; k++) |
3726 | INIT_LIST_HEAD(&__ctx->rq_lists[k]); | |
3727 | ||
320ae51f JA |
3728 | __ctx->queue = q; |
3729 | ||
320ae51f JA |
3730 | /* |
3731 | * Set local node, IFF we have more than one hw queue. If | |
3732 | * not, we remain on the home node of the device | |
3733 | */ | |
b3c661b1 JA |
3734 | for (j = 0; j < set->nr_maps; j++) { |
3735 | hctx = blk_mq_map_queue_type(q, j, i); | |
3736 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
576e85c5 | 3737 | hctx->numa_node = cpu_to_node(i); |
b3c661b1 | 3738 | } |
320ae51f JA |
3739 | } |
3740 | } | |
3741 | ||
63064be1 JG |
3742 | struct blk_mq_tags *blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set, |
3743 | unsigned int hctx_idx, | |
3744 | unsigned int depth) | |
cc71a6f4 | 3745 | { |
63064be1 JG |
3746 | struct blk_mq_tags *tags; |
3747 | int ret; | |
cc71a6f4 | 3748 | |
e155b0c2 | 3749 | tags = blk_mq_alloc_rq_map(set, hctx_idx, depth, set->reserved_tags); |
63064be1 JG |
3750 | if (!tags) |
3751 | return NULL; | |
cc71a6f4 | 3752 | |
63064be1 JG |
3753 | ret = blk_mq_alloc_rqs(set, tags, hctx_idx, depth); |
3754 | if (ret) { | |
e155b0c2 | 3755 | blk_mq_free_rq_map(tags); |
63064be1 JG |
3756 | return NULL; |
3757 | } | |
cc71a6f4 | 3758 | |
63064be1 | 3759 | return tags; |
cc71a6f4 JA |
3760 | } |
3761 | ||
63064be1 JG |
3762 | static bool __blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set, |
3763 | int hctx_idx) | |
cc71a6f4 | 3764 | { |
079a2e3e JG |
3765 | if (blk_mq_is_shared_tags(set->flags)) { |
3766 | set->tags[hctx_idx] = set->shared_tags; | |
1c0706a7 | 3767 | |
e155b0c2 | 3768 | return true; |
bd166ef1 | 3769 | } |
e155b0c2 | 3770 | |
63064be1 JG |
3771 | set->tags[hctx_idx] = blk_mq_alloc_map_and_rqs(set, hctx_idx, |
3772 | set->queue_depth); | |
3773 | ||
3774 | return set->tags[hctx_idx]; | |
cc71a6f4 JA |
3775 | } |
3776 | ||
645db34e JG |
3777 | void blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set, |
3778 | struct blk_mq_tags *tags, | |
3779 | unsigned int hctx_idx) | |
cc71a6f4 | 3780 | { |
645db34e JG |
3781 | if (tags) { |
3782 | blk_mq_free_rqs(set, tags, hctx_idx); | |
e155b0c2 | 3783 | blk_mq_free_rq_map(tags); |
bd166ef1 | 3784 | } |
cc71a6f4 JA |
3785 | } |
3786 | ||
e155b0c2 JG |
3787 | static void __blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set, |
3788 | unsigned int hctx_idx) | |
3789 | { | |
079a2e3e | 3790 | if (!blk_mq_is_shared_tags(set->flags)) |
e155b0c2 JG |
3791 | blk_mq_free_map_and_rqs(set, set->tags[hctx_idx], hctx_idx); |
3792 | ||
3793 | set->tags[hctx_idx] = NULL; | |
cc71a6f4 JA |
3794 | } |
3795 | ||
4b855ad3 | 3796 | static void blk_mq_map_swqueue(struct request_queue *q) |
320ae51f | 3797 | { |
4f481208 ML |
3798 | unsigned int j, hctx_idx; |
3799 | unsigned long i; | |
320ae51f JA |
3800 | struct blk_mq_hw_ctx *hctx; |
3801 | struct blk_mq_ctx *ctx; | |
2a34c087 | 3802 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f JA |
3803 | |
3804 | queue_for_each_hw_ctx(q, hctx, i) { | |
e4043dcf | 3805 | cpumask_clear(hctx->cpumask); |
320ae51f | 3806 | hctx->nr_ctx = 0; |
d416c92c | 3807 | hctx->dispatch_from = NULL; |
320ae51f JA |
3808 | } |
3809 | ||
3810 | /* | |
4b855ad3 | 3811 | * Map software to hardware queues. |
4412efec ML |
3812 | * |
3813 | * If the cpu isn't present, the cpu is mapped to first hctx. | |
320ae51f | 3814 | */ |
20e4d813 | 3815 | for_each_possible_cpu(i) { |
4412efec | 3816 | |
897bb0c7 | 3817 | ctx = per_cpu_ptr(q->queue_ctx, i); |
b3c661b1 | 3818 | for (j = 0; j < set->nr_maps; j++) { |
bb94aea1 JW |
3819 | if (!set->map[j].nr_queues) { |
3820 | ctx->hctxs[j] = blk_mq_map_queue_type(q, | |
3821 | HCTX_TYPE_DEFAULT, i); | |
e5edd5f2 | 3822 | continue; |
bb94aea1 | 3823 | } |
fd689871 ML |
3824 | hctx_idx = set->map[j].mq_map[i]; |
3825 | /* unmapped hw queue can be remapped after CPU topo changed */ | |
3826 | if (!set->tags[hctx_idx] && | |
63064be1 | 3827 | !__blk_mq_alloc_map_and_rqs(set, hctx_idx)) { |
fd689871 ML |
3828 | /* |
3829 | * If tags initialization fail for some hctx, | |
3830 | * that hctx won't be brought online. In this | |
3831 | * case, remap the current ctx to hctx[0] which | |
3832 | * is guaranteed to always have tags allocated | |
3833 | */ | |
3834 | set->map[j].mq_map[i] = 0; | |
3835 | } | |
e5edd5f2 | 3836 | |
b3c661b1 | 3837 | hctx = blk_mq_map_queue_type(q, j, i); |
8ccdf4a3 | 3838 | ctx->hctxs[j] = hctx; |
b3c661b1 JA |
3839 | /* |
3840 | * If the CPU is already set in the mask, then we've | |
3841 | * mapped this one already. This can happen if | |
3842 | * devices share queues across queue maps. | |
3843 | */ | |
3844 | if (cpumask_test_cpu(i, hctx->cpumask)) | |
3845 | continue; | |
3846 | ||
3847 | cpumask_set_cpu(i, hctx->cpumask); | |
3848 | hctx->type = j; | |
3849 | ctx->index_hw[hctx->type] = hctx->nr_ctx; | |
3850 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
3851 | ||
3852 | /* | |
3853 | * If the nr_ctx type overflows, we have exceeded the | |
3854 | * amount of sw queues we can support. | |
3855 | */ | |
3856 | BUG_ON(!hctx->nr_ctx); | |
3857 | } | |
bb94aea1 JW |
3858 | |
3859 | for (; j < HCTX_MAX_TYPES; j++) | |
3860 | ctx->hctxs[j] = blk_mq_map_queue_type(q, | |
3861 | HCTX_TYPE_DEFAULT, i); | |
320ae51f | 3862 | } |
506e931f JA |
3863 | |
3864 | queue_for_each_hw_ctx(q, hctx, i) { | |
4412efec ML |
3865 | /* |
3866 | * If no software queues are mapped to this hardware queue, | |
3867 | * disable it and free the request entries. | |
3868 | */ | |
3869 | if (!hctx->nr_ctx) { | |
3870 | /* Never unmap queue 0. We need it as a | |
3871 | * fallback in case of a new remap fails | |
3872 | * allocation | |
3873 | */ | |
e155b0c2 JG |
3874 | if (i) |
3875 | __blk_mq_free_map_and_rqs(set, i); | |
4412efec ML |
3876 | |
3877 | hctx->tags = NULL; | |
3878 | continue; | |
3879 | } | |
484b4061 | 3880 | |
2a34c087 ML |
3881 | hctx->tags = set->tags[i]; |
3882 | WARN_ON(!hctx->tags); | |
3883 | ||
889fa31f CY |
3884 | /* |
3885 | * Set the map size to the number of mapped software queues. | |
3886 | * This is more accurate and more efficient than looping | |
3887 | * over all possibly mapped software queues. | |
3888 | */ | |
88459642 | 3889 | sbitmap_resize(&hctx->ctx_map, hctx->nr_ctx); |
889fa31f | 3890 | |
484b4061 JA |
3891 | /* |
3892 | * Initialize batch roundrobin counts | |
3893 | */ | |
f82ddf19 | 3894 | hctx->next_cpu = blk_mq_first_mapped_cpu(hctx); |
506e931f JA |
3895 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; |
3896 | } | |
320ae51f JA |
3897 | } |
3898 | ||
8e8320c9 JA |
3899 | /* |
3900 | * Caller needs to ensure that we're either frozen/quiesced, or that | |
3901 | * the queue isn't live yet. | |
3902 | */ | |
2404e607 | 3903 | static void queue_set_hctx_shared(struct request_queue *q, bool shared) |
0d2602ca JA |
3904 | { |
3905 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 3906 | unsigned long i; |
0d2602ca | 3907 | |
2404e607 | 3908 | queue_for_each_hw_ctx(q, hctx, i) { |
454bb677 | 3909 | if (shared) { |
51db1c37 | 3910 | hctx->flags |= BLK_MQ_F_TAG_QUEUE_SHARED; |
454bb677 YK |
3911 | } else { |
3912 | blk_mq_tag_idle(hctx); | |
51db1c37 | 3913 | hctx->flags &= ~BLK_MQ_F_TAG_QUEUE_SHARED; |
454bb677 | 3914 | } |
2404e607 JM |
3915 | } |
3916 | } | |
3917 | ||
655ac300 HR |
3918 | static void blk_mq_update_tag_set_shared(struct blk_mq_tag_set *set, |
3919 | bool shared) | |
2404e607 JM |
3920 | { |
3921 | struct request_queue *q; | |
0d2602ca | 3922 | |
705cda97 BVA |
3923 | lockdep_assert_held(&set->tag_list_lock); |
3924 | ||
0d2602ca JA |
3925 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
3926 | blk_mq_freeze_queue(q); | |
2404e607 | 3927 | queue_set_hctx_shared(q, shared); |
0d2602ca JA |
3928 | blk_mq_unfreeze_queue(q); |
3929 | } | |
3930 | } | |
3931 | ||
3932 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
3933 | { | |
3934 | struct blk_mq_tag_set *set = q->tag_set; | |
3935 | ||
0d2602ca | 3936 | mutex_lock(&set->tag_list_lock); |
08c875cb | 3937 | list_del(&q->tag_set_list); |
2404e607 JM |
3938 | if (list_is_singular(&set->tag_list)) { |
3939 | /* just transitioned to unshared */ | |
51db1c37 | 3940 | set->flags &= ~BLK_MQ_F_TAG_QUEUE_SHARED; |
2404e607 | 3941 | /* update existing queue */ |
655ac300 | 3942 | blk_mq_update_tag_set_shared(set, false); |
2404e607 | 3943 | } |
0d2602ca | 3944 | mutex_unlock(&set->tag_list_lock); |
a347c7ad | 3945 | INIT_LIST_HEAD(&q->tag_set_list); |
0d2602ca JA |
3946 | } |
3947 | ||
3948 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
3949 | struct request_queue *q) | |
3950 | { | |
0d2602ca | 3951 | mutex_lock(&set->tag_list_lock); |
2404e607 | 3952 | |
ff821d27 JA |
3953 | /* |
3954 | * Check to see if we're transitioning to shared (from 1 to 2 queues). | |
3955 | */ | |
3956 | if (!list_empty(&set->tag_list) && | |
51db1c37 ML |
3957 | !(set->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) { |
3958 | set->flags |= BLK_MQ_F_TAG_QUEUE_SHARED; | |
2404e607 | 3959 | /* update existing queue */ |
655ac300 | 3960 | blk_mq_update_tag_set_shared(set, true); |
2404e607 | 3961 | } |
51db1c37 | 3962 | if (set->flags & BLK_MQ_F_TAG_QUEUE_SHARED) |
2404e607 | 3963 | queue_set_hctx_shared(q, true); |
08c875cb | 3964 | list_add_tail(&q->tag_set_list, &set->tag_list); |
2404e607 | 3965 | |
0d2602ca JA |
3966 | mutex_unlock(&set->tag_list_lock); |
3967 | } | |
3968 | ||
1db4909e ML |
3969 | /* All allocations will be freed in release handler of q->mq_kobj */ |
3970 | static int blk_mq_alloc_ctxs(struct request_queue *q) | |
3971 | { | |
3972 | struct blk_mq_ctxs *ctxs; | |
3973 | int cpu; | |
3974 | ||
3975 | ctxs = kzalloc(sizeof(*ctxs), GFP_KERNEL); | |
3976 | if (!ctxs) | |
3977 | return -ENOMEM; | |
3978 | ||
3979 | ctxs->queue_ctx = alloc_percpu(struct blk_mq_ctx); | |
3980 | if (!ctxs->queue_ctx) | |
3981 | goto fail; | |
3982 | ||
3983 | for_each_possible_cpu(cpu) { | |
3984 | struct blk_mq_ctx *ctx = per_cpu_ptr(ctxs->queue_ctx, cpu); | |
3985 | ctx->ctxs = ctxs; | |
3986 | } | |
3987 | ||
3988 | q->mq_kobj = &ctxs->kobj; | |
3989 | q->queue_ctx = ctxs->queue_ctx; | |
3990 | ||
3991 | return 0; | |
3992 | fail: | |
3993 | kfree(ctxs); | |
3994 | return -ENOMEM; | |
3995 | } | |
3996 | ||
e09aae7e ML |
3997 | /* |
3998 | * It is the actual release handler for mq, but we do it from | |
3999 | * request queue's release handler for avoiding use-after-free | |
4000 | * and headache because q->mq_kobj shouldn't have been introduced, | |
4001 | * but we can't group ctx/kctx kobj without it. | |
4002 | */ | |
4003 | void blk_mq_release(struct request_queue *q) | |
4004 | { | |
2f8f1336 | 4005 | struct blk_mq_hw_ctx *hctx, *next; |
4f481208 | 4006 | unsigned long i; |
e09aae7e | 4007 | |
2f8f1336 ML |
4008 | queue_for_each_hw_ctx(q, hctx, i) |
4009 | WARN_ON_ONCE(hctx && list_empty(&hctx->hctx_list)); | |
4010 | ||
4011 | /* all hctx are in .unused_hctx_list now */ | |
4012 | list_for_each_entry_safe(hctx, next, &q->unused_hctx_list, hctx_list) { | |
4013 | list_del_init(&hctx->hctx_list); | |
6c8b232e | 4014 | kobject_put(&hctx->kobj); |
c3b4afca | 4015 | } |
e09aae7e | 4016 | |
4e5cc99e | 4017 | xa_destroy(&q->hctx_table); |
e09aae7e | 4018 | |
7ea5fe31 ML |
4019 | /* |
4020 | * release .mq_kobj and sw queue's kobject now because | |
4021 | * both share lifetime with request queue. | |
4022 | */ | |
4023 | blk_mq_sysfs_deinit(q); | |
e09aae7e ML |
4024 | } |
4025 | ||
5ec780a6 | 4026 | static struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set, |
2f227bb9 | 4027 | void *queuedata) |
b62c21b7 | 4028 | { |
26a9750a CH |
4029 | struct request_queue *q; |
4030 | int ret; | |
b62c21b7 | 4031 | |
80bd4a7a | 4032 | q = blk_alloc_queue(set->numa_node); |
26a9750a | 4033 | if (!q) |
b62c21b7 | 4034 | return ERR_PTR(-ENOMEM); |
26a9750a CH |
4035 | q->queuedata = queuedata; |
4036 | ret = blk_mq_init_allocated_queue(set, q); | |
4037 | if (ret) { | |
6f8191fd | 4038 | blk_put_queue(q); |
26a9750a CH |
4039 | return ERR_PTR(ret); |
4040 | } | |
b62c21b7 MS |
4041 | return q; |
4042 | } | |
2f227bb9 CH |
4043 | |
4044 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) | |
4045 | { | |
4046 | return blk_mq_init_queue_data(set, NULL); | |
4047 | } | |
b62c21b7 MS |
4048 | EXPORT_SYMBOL(blk_mq_init_queue); |
4049 | ||
6f8191fd CH |
4050 | /** |
4051 | * blk_mq_destroy_queue - shutdown a request queue | |
4052 | * @q: request queue to shutdown | |
4053 | * | |
81ea42b9 BVA |
4054 | * This shuts down a request queue allocated by blk_mq_init_queue(). All future |
4055 | * requests will be failed with -ENODEV. The caller is responsible for dropping | |
4056 | * the reference from blk_mq_init_queue() by calling blk_put_queue(). | |
6f8191fd CH |
4057 | * |
4058 | * Context: can sleep | |
4059 | */ | |
4060 | void blk_mq_destroy_queue(struct request_queue *q) | |
4061 | { | |
4062 | WARN_ON_ONCE(!queue_is_mq(q)); | |
4063 | WARN_ON_ONCE(blk_queue_registered(q)); | |
4064 | ||
4065 | might_sleep(); | |
4066 | ||
4067 | blk_queue_flag_set(QUEUE_FLAG_DYING, q); | |
4068 | blk_queue_start_drain(q); | |
56c1ee92 | 4069 | blk_mq_freeze_queue_wait(q); |
6f8191fd CH |
4070 | |
4071 | blk_sync_queue(q); | |
4072 | blk_mq_cancel_work_sync(q); | |
4073 | blk_mq_exit_queue(q); | |
6f8191fd CH |
4074 | } |
4075 | EXPORT_SYMBOL(blk_mq_destroy_queue); | |
4076 | ||
4dcc4874 CH |
4077 | struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata, |
4078 | struct lock_class_key *lkclass) | |
9316a9ed JA |
4079 | { |
4080 | struct request_queue *q; | |
b461dfc4 | 4081 | struct gendisk *disk; |
9316a9ed | 4082 | |
b461dfc4 CH |
4083 | q = blk_mq_init_queue_data(set, queuedata); |
4084 | if (IS_ERR(q)) | |
4085 | return ERR_CAST(q); | |
9316a9ed | 4086 | |
4a1fa41d | 4087 | disk = __alloc_disk_node(q, set->numa_node, lkclass); |
b461dfc4 | 4088 | if (!disk) { |
0a3e5cc7 | 4089 | blk_mq_destroy_queue(q); |
2b3f056f | 4090 | blk_put_queue(q); |
b461dfc4 | 4091 | return ERR_PTR(-ENOMEM); |
9316a9ed | 4092 | } |
6f8191fd | 4093 | set_bit(GD_OWNS_QUEUE, &disk->state); |
b461dfc4 | 4094 | return disk; |
9316a9ed | 4095 | } |
b461dfc4 | 4096 | EXPORT_SYMBOL(__blk_mq_alloc_disk); |
9316a9ed | 4097 | |
6f8191fd CH |
4098 | struct gendisk *blk_mq_alloc_disk_for_queue(struct request_queue *q, |
4099 | struct lock_class_key *lkclass) | |
4100 | { | |
22c17e27 CH |
4101 | struct gendisk *disk; |
4102 | ||
6f8191fd CH |
4103 | if (!blk_get_queue(q)) |
4104 | return NULL; | |
22c17e27 CH |
4105 | disk = __alloc_disk_node(q, NUMA_NO_NODE, lkclass); |
4106 | if (!disk) | |
4107 | blk_put_queue(q); | |
4108 | return disk; | |
6f8191fd CH |
4109 | } |
4110 | EXPORT_SYMBOL(blk_mq_alloc_disk_for_queue); | |
4111 | ||
34d11ffa JW |
4112 | static struct blk_mq_hw_ctx *blk_mq_alloc_and_init_hctx( |
4113 | struct blk_mq_tag_set *set, struct request_queue *q, | |
4114 | int hctx_idx, int node) | |
4115 | { | |
2f8f1336 | 4116 | struct blk_mq_hw_ctx *hctx = NULL, *tmp; |
34d11ffa | 4117 | |
2f8f1336 ML |
4118 | /* reuse dead hctx first */ |
4119 | spin_lock(&q->unused_hctx_lock); | |
4120 | list_for_each_entry(tmp, &q->unused_hctx_list, hctx_list) { | |
4121 | if (tmp->numa_node == node) { | |
4122 | hctx = tmp; | |
4123 | break; | |
4124 | } | |
4125 | } | |
4126 | if (hctx) | |
4127 | list_del_init(&hctx->hctx_list); | |
4128 | spin_unlock(&q->unused_hctx_lock); | |
4129 | ||
4130 | if (!hctx) | |
4131 | hctx = blk_mq_alloc_hctx(q, set, node); | |
34d11ffa | 4132 | if (!hctx) |
7c6c5b7c | 4133 | goto fail; |
34d11ffa | 4134 | |
7c6c5b7c ML |
4135 | if (blk_mq_init_hctx(q, set, hctx, hctx_idx)) |
4136 | goto free_hctx; | |
34d11ffa JW |
4137 | |
4138 | return hctx; | |
7c6c5b7c ML |
4139 | |
4140 | free_hctx: | |
4141 | kobject_put(&hctx->kobj); | |
4142 | fail: | |
4143 | return NULL; | |
34d11ffa JW |
4144 | } |
4145 | ||
868f2f0b KB |
4146 | static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, |
4147 | struct request_queue *q) | |
320ae51f | 4148 | { |
4e5cc99e ML |
4149 | struct blk_mq_hw_ctx *hctx; |
4150 | unsigned long i, j; | |
ac0d6b92 | 4151 | |
fb350e0a ML |
4152 | /* protect against switching io scheduler */ |
4153 | mutex_lock(&q->sysfs_lock); | |
24d2f903 | 4154 | for (i = 0; i < set->nr_hw_queues; i++) { |
306f13ee | 4155 | int old_node; |
4d805131 | 4156 | int node = blk_mq_get_hctx_node(set, i); |
4e5cc99e | 4157 | struct blk_mq_hw_ctx *old_hctx = xa_load(&q->hctx_table, i); |
868f2f0b | 4158 | |
306f13ee ML |
4159 | if (old_hctx) { |
4160 | old_node = old_hctx->numa_node; | |
4161 | blk_mq_exit_hctx(q, set, old_hctx, i); | |
4162 | } | |
868f2f0b | 4163 | |
4e5cc99e | 4164 | if (!blk_mq_alloc_and_init_hctx(set, q, i, node)) { |
306f13ee | 4165 | if (!old_hctx) |
34d11ffa | 4166 | break; |
306f13ee ML |
4167 | pr_warn("Allocate new hctx on node %d fails, fallback to previous one on node %d\n", |
4168 | node, old_node); | |
4e5cc99e ML |
4169 | hctx = blk_mq_alloc_and_init_hctx(set, q, i, old_node); |
4170 | WARN_ON_ONCE(!hctx); | |
868f2f0b | 4171 | } |
320ae51f | 4172 | } |
e01ad46d JW |
4173 | /* |
4174 | * Increasing nr_hw_queues fails. Free the newly allocated | |
4175 | * hctxs and keep the previous q->nr_hw_queues. | |
4176 | */ | |
4177 | if (i != set->nr_hw_queues) { | |
4178 | j = q->nr_hw_queues; | |
e01ad46d JW |
4179 | } else { |
4180 | j = i; | |
e01ad46d JW |
4181 | q->nr_hw_queues = set->nr_hw_queues; |
4182 | } | |
34d11ffa | 4183 | |
4e5cc99e ML |
4184 | xa_for_each_start(&q->hctx_table, j, hctx, j) |
4185 | blk_mq_exit_hctx(q, set, hctx, j); | |
fb350e0a | 4186 | mutex_unlock(&q->sysfs_lock); |
868f2f0b KB |
4187 | } |
4188 | ||
42ee3061 ML |
4189 | static void blk_mq_update_poll_flag(struct request_queue *q) |
4190 | { | |
4191 | struct blk_mq_tag_set *set = q->tag_set; | |
4192 | ||
4193 | if (set->nr_maps > HCTX_TYPE_POLL && | |
4194 | set->map[HCTX_TYPE_POLL].nr_queues) | |
4195 | blk_queue_flag_set(QUEUE_FLAG_POLL, q); | |
4196 | else | |
4197 | blk_queue_flag_clear(QUEUE_FLAG_POLL, q); | |
4198 | } | |
4199 | ||
26a9750a CH |
4200 | int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, |
4201 | struct request_queue *q) | |
868f2f0b | 4202 | { |
66841672 ML |
4203 | /* mark the queue as mq asap */ |
4204 | q->mq_ops = set->ops; | |
4205 | ||
1db4909e | 4206 | if (blk_mq_alloc_ctxs(q)) |
54bdd67d | 4207 | goto err_exit; |
868f2f0b | 4208 | |
737f98cf ML |
4209 | /* init q->mq_kobj and sw queues' kobjects */ |
4210 | blk_mq_sysfs_init(q); | |
4211 | ||
2f8f1336 ML |
4212 | INIT_LIST_HEAD(&q->unused_hctx_list); |
4213 | spin_lock_init(&q->unused_hctx_lock); | |
4214 | ||
4e5cc99e ML |
4215 | xa_init(&q->hctx_table); |
4216 | ||
868f2f0b KB |
4217 | blk_mq_realloc_hw_ctxs(set, q); |
4218 | if (!q->nr_hw_queues) | |
4219 | goto err_hctxs; | |
320ae51f | 4220 | |
287922eb | 4221 | INIT_WORK(&q->timeout_work, blk_mq_timeout_work); |
e56f698b | 4222 | blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); |
320ae51f | 4223 | |
a8908939 | 4224 | q->tag_set = set; |
320ae51f | 4225 | |
94eddfbe | 4226 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
42ee3061 | 4227 | blk_mq_update_poll_flag(q); |
320ae51f | 4228 | |
2849450a | 4229 | INIT_DELAYED_WORK(&q->requeue_work, blk_mq_requeue_work); |
9a67aa52 | 4230 | INIT_LIST_HEAD(&q->flush_list); |
6fca6a61 CH |
4231 | INIT_LIST_HEAD(&q->requeue_list); |
4232 | spin_lock_init(&q->requeue_lock); | |
4233 | ||
eba71768 JA |
4234 | q->nr_requests = set->queue_depth; |
4235 | ||
24d2f903 | 4236 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
0d2602ca | 4237 | blk_mq_add_queue_tag_set(set, q); |
4b855ad3 | 4238 | blk_mq_map_swqueue(q); |
26a9750a | 4239 | return 0; |
18741986 | 4240 | |
320ae51f | 4241 | err_hctxs: |
943f45b9 | 4242 | blk_mq_release(q); |
c7de5726 ML |
4243 | err_exit: |
4244 | q->mq_ops = NULL; | |
26a9750a | 4245 | return -ENOMEM; |
320ae51f | 4246 | } |
b62c21b7 | 4247 | EXPORT_SYMBOL(blk_mq_init_allocated_queue); |
320ae51f | 4248 | |
c7e2d94b ML |
4249 | /* tags can _not_ be used after returning from blk_mq_exit_queue */ |
4250 | void blk_mq_exit_queue(struct request_queue *q) | |
320ae51f | 4251 | { |
630ef623 | 4252 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 4253 | |
630ef623 | 4254 | /* Checks hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED. */ |
624dbe47 | 4255 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
630ef623 BVA |
4256 | /* May clear BLK_MQ_F_TAG_QUEUE_SHARED in hctx->flags. */ |
4257 | blk_mq_del_queue_tag_set(q); | |
320ae51f | 4258 | } |
320ae51f | 4259 | |
a5164405 JA |
4260 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
4261 | { | |
4262 | int i; | |
4263 | ||
079a2e3e JG |
4264 | if (blk_mq_is_shared_tags(set->flags)) { |
4265 | set->shared_tags = blk_mq_alloc_map_and_rqs(set, | |
e155b0c2 JG |
4266 | BLK_MQ_NO_HCTX_IDX, |
4267 | set->queue_depth); | |
079a2e3e | 4268 | if (!set->shared_tags) |
e155b0c2 JG |
4269 | return -ENOMEM; |
4270 | } | |
4271 | ||
8229cca8 | 4272 | for (i = 0; i < set->nr_hw_queues; i++) { |
63064be1 | 4273 | if (!__blk_mq_alloc_map_and_rqs(set, i)) |
a5164405 | 4274 | goto out_unwind; |
8229cca8 XT |
4275 | cond_resched(); |
4276 | } | |
a5164405 JA |
4277 | |
4278 | return 0; | |
4279 | ||
4280 | out_unwind: | |
4281 | while (--i >= 0) | |
e155b0c2 JG |
4282 | __blk_mq_free_map_and_rqs(set, i); |
4283 | ||
079a2e3e JG |
4284 | if (blk_mq_is_shared_tags(set->flags)) { |
4285 | blk_mq_free_map_and_rqs(set, set->shared_tags, | |
e155b0c2 | 4286 | BLK_MQ_NO_HCTX_IDX); |
645db34e | 4287 | } |
a5164405 | 4288 | |
a5164405 JA |
4289 | return -ENOMEM; |
4290 | } | |
4291 | ||
4292 | /* | |
4293 | * Allocate the request maps associated with this tag_set. Note that this | |
4294 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
4295 | * will be updated to reflect the allocated depth. | |
4296 | */ | |
63064be1 | 4297 | static int blk_mq_alloc_set_map_and_rqs(struct blk_mq_tag_set *set) |
a5164405 JA |
4298 | { |
4299 | unsigned int depth; | |
4300 | int err; | |
4301 | ||
4302 | depth = set->queue_depth; | |
4303 | do { | |
4304 | err = __blk_mq_alloc_rq_maps(set); | |
4305 | if (!err) | |
4306 | break; | |
4307 | ||
4308 | set->queue_depth >>= 1; | |
4309 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
4310 | err = -ENOMEM; | |
4311 | break; | |
4312 | } | |
4313 | } while (set->queue_depth); | |
4314 | ||
4315 | if (!set->queue_depth || err) { | |
4316 | pr_err("blk-mq: failed to allocate request map\n"); | |
4317 | return -ENOMEM; | |
4318 | } | |
4319 | ||
4320 | if (depth != set->queue_depth) | |
4321 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
4322 | depth, set->queue_depth); | |
4323 | ||
4324 | return 0; | |
4325 | } | |
4326 | ||
a4e1d0b7 | 4327 | static void blk_mq_update_queue_map(struct blk_mq_tag_set *set) |
ebe8bddb | 4328 | { |
6e66b493 BVA |
4329 | /* |
4330 | * blk_mq_map_queues() and multiple .map_queues() implementations | |
4331 | * expect that set->map[HCTX_TYPE_DEFAULT].nr_queues is set to the | |
4332 | * number of hardware queues. | |
4333 | */ | |
4334 | if (set->nr_maps == 1) | |
4335 | set->map[HCTX_TYPE_DEFAULT].nr_queues = set->nr_hw_queues; | |
4336 | ||
59388702 | 4337 | if (set->ops->map_queues && !is_kdump_kernel()) { |
b3c661b1 JA |
4338 | int i; |
4339 | ||
7d4901a9 ML |
4340 | /* |
4341 | * transport .map_queues is usually done in the following | |
4342 | * way: | |
4343 | * | |
4344 | * for (queue = 0; queue < set->nr_hw_queues; queue++) { | |
4345 | * mask = get_cpu_mask(queue) | |
4346 | * for_each_cpu(cpu, mask) | |
b3c661b1 | 4347 | * set->map[x].mq_map[cpu] = queue; |
7d4901a9 ML |
4348 | * } |
4349 | * | |
4350 | * When we need to remap, the table has to be cleared for | |
4351 | * killing stale mapping since one CPU may not be mapped | |
4352 | * to any hw queue. | |
4353 | */ | |
b3c661b1 JA |
4354 | for (i = 0; i < set->nr_maps; i++) |
4355 | blk_mq_clear_mq_map(&set->map[i]); | |
7d4901a9 | 4356 | |
a4e1d0b7 | 4357 | set->ops->map_queues(set); |
b3c661b1 JA |
4358 | } else { |
4359 | BUG_ON(set->nr_maps > 1); | |
a4e1d0b7 | 4360 | blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]); |
b3c661b1 | 4361 | } |
ebe8bddb OS |
4362 | } |
4363 | ||
f7e76dbc | 4364 | static int blk_mq_realloc_tag_set_tags(struct blk_mq_tag_set *set, |
ee9d5521 | 4365 | int new_nr_hw_queues) |
f7e76dbc BVA |
4366 | { |
4367 | struct blk_mq_tags **new_tags; | |
4368 | ||
ee9d5521 | 4369 | if (set->nr_hw_queues >= new_nr_hw_queues) |
d4b2e0d4 | 4370 | goto done; |
f7e76dbc BVA |
4371 | |
4372 | new_tags = kcalloc_node(new_nr_hw_queues, sizeof(struct blk_mq_tags *), | |
4373 | GFP_KERNEL, set->numa_node); | |
4374 | if (!new_tags) | |
4375 | return -ENOMEM; | |
4376 | ||
4377 | if (set->tags) | |
ee9d5521 | 4378 | memcpy(new_tags, set->tags, set->nr_hw_queues * |
f7e76dbc BVA |
4379 | sizeof(*set->tags)); |
4380 | kfree(set->tags); | |
4381 | set->tags = new_tags; | |
d4b2e0d4 | 4382 | done: |
f7e76dbc | 4383 | set->nr_hw_queues = new_nr_hw_queues; |
f7e76dbc BVA |
4384 | return 0; |
4385 | } | |
4386 | ||
a4391c64 JA |
4387 | /* |
4388 | * Alloc a tag set to be associated with one or more request queues. | |
4389 | * May fail with EINVAL for various error conditions. May adjust the | |
c018c84f | 4390 | * requested depth down, if it's too large. In that case, the set |
a4391c64 JA |
4391 | * value will be stored in set->queue_depth. |
4392 | */ | |
24d2f903 CH |
4393 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
4394 | { | |
b3c661b1 | 4395 | int i, ret; |
da695ba2 | 4396 | |
205fb5f5 BVA |
4397 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
4398 | ||
24d2f903 CH |
4399 | if (!set->nr_hw_queues) |
4400 | return -EINVAL; | |
a4391c64 | 4401 | if (!set->queue_depth) |
24d2f903 CH |
4402 | return -EINVAL; |
4403 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
4404 | return -EINVAL; | |
4405 | ||
7d7e0f90 | 4406 | if (!set->ops->queue_rq) |
24d2f903 CH |
4407 | return -EINVAL; |
4408 | ||
de148297 ML |
4409 | if (!set->ops->get_budget ^ !set->ops->put_budget) |
4410 | return -EINVAL; | |
4411 | ||
a4391c64 JA |
4412 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
4413 | pr_info("blk-mq: reduced tag depth to %u\n", | |
4414 | BLK_MQ_MAX_DEPTH); | |
4415 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
4416 | } | |
24d2f903 | 4417 | |
b3c661b1 JA |
4418 | if (!set->nr_maps) |
4419 | set->nr_maps = 1; | |
4420 | else if (set->nr_maps > HCTX_MAX_TYPES) | |
4421 | return -EINVAL; | |
4422 | ||
6637fadf SL |
4423 | /* |
4424 | * If a crashdump is active, then we are potentially in a very | |
4425 | * memory constrained environment. Limit us to 1 queue and | |
4426 | * 64 tags to prevent using too much memory. | |
4427 | */ | |
4428 | if (is_kdump_kernel()) { | |
4429 | set->nr_hw_queues = 1; | |
59388702 | 4430 | set->nr_maps = 1; |
6637fadf SL |
4431 | set->queue_depth = min(64U, set->queue_depth); |
4432 | } | |
868f2f0b | 4433 | /* |
392546ae JA |
4434 | * There is no use for more h/w queues than cpus if we just have |
4435 | * a single map | |
868f2f0b | 4436 | */ |
392546ae | 4437 | if (set->nr_maps == 1 && set->nr_hw_queues > nr_cpu_ids) |
868f2f0b | 4438 | set->nr_hw_queues = nr_cpu_ids; |
6637fadf | 4439 | |
80bd4a7a CH |
4440 | if (set->flags & BLK_MQ_F_BLOCKING) { |
4441 | set->srcu = kmalloc(sizeof(*set->srcu), GFP_KERNEL); | |
4442 | if (!set->srcu) | |
4443 | return -ENOMEM; | |
4444 | ret = init_srcu_struct(set->srcu); | |
4445 | if (ret) | |
4446 | goto out_free_srcu; | |
4447 | } | |
24d2f903 | 4448 | |
da695ba2 | 4449 | ret = -ENOMEM; |
5ee20298 CH |
4450 | set->tags = kcalloc_node(set->nr_hw_queues, |
4451 | sizeof(struct blk_mq_tags *), GFP_KERNEL, | |
4452 | set->numa_node); | |
4453 | if (!set->tags) | |
80bd4a7a | 4454 | goto out_cleanup_srcu; |
24d2f903 | 4455 | |
b3c661b1 JA |
4456 | for (i = 0; i < set->nr_maps; i++) { |
4457 | set->map[i].mq_map = kcalloc_node(nr_cpu_ids, | |
07b35eb5 | 4458 | sizeof(set->map[i].mq_map[0]), |
b3c661b1 JA |
4459 | GFP_KERNEL, set->numa_node); |
4460 | if (!set->map[i].mq_map) | |
4461 | goto out_free_mq_map; | |
59388702 | 4462 | set->map[i].nr_queues = is_kdump_kernel() ? 1 : set->nr_hw_queues; |
b3c661b1 | 4463 | } |
bdd17e75 | 4464 | |
a4e1d0b7 | 4465 | blk_mq_update_queue_map(set); |
da695ba2 | 4466 | |
63064be1 | 4467 | ret = blk_mq_alloc_set_map_and_rqs(set); |
da695ba2 | 4468 | if (ret) |
bdd17e75 | 4469 | goto out_free_mq_map; |
24d2f903 | 4470 | |
0d2602ca JA |
4471 | mutex_init(&set->tag_list_lock); |
4472 | INIT_LIST_HEAD(&set->tag_list); | |
4473 | ||
24d2f903 | 4474 | return 0; |
bdd17e75 CH |
4475 | |
4476 | out_free_mq_map: | |
b3c661b1 JA |
4477 | for (i = 0; i < set->nr_maps; i++) { |
4478 | kfree(set->map[i].mq_map); | |
4479 | set->map[i].mq_map = NULL; | |
4480 | } | |
5676e7b6 RE |
4481 | kfree(set->tags); |
4482 | set->tags = NULL; | |
80bd4a7a CH |
4483 | out_cleanup_srcu: |
4484 | if (set->flags & BLK_MQ_F_BLOCKING) | |
4485 | cleanup_srcu_struct(set->srcu); | |
4486 | out_free_srcu: | |
4487 | if (set->flags & BLK_MQ_F_BLOCKING) | |
4488 | kfree(set->srcu); | |
da695ba2 | 4489 | return ret; |
24d2f903 CH |
4490 | } |
4491 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
4492 | ||
cdb14e0f CH |
4493 | /* allocate and initialize a tagset for a simple single-queue device */ |
4494 | int blk_mq_alloc_sq_tag_set(struct blk_mq_tag_set *set, | |
4495 | const struct blk_mq_ops *ops, unsigned int queue_depth, | |
4496 | unsigned int set_flags) | |
4497 | { | |
4498 | memset(set, 0, sizeof(*set)); | |
4499 | set->ops = ops; | |
4500 | set->nr_hw_queues = 1; | |
4501 | set->nr_maps = 1; | |
4502 | set->queue_depth = queue_depth; | |
4503 | set->numa_node = NUMA_NO_NODE; | |
4504 | set->flags = set_flags; | |
4505 | return blk_mq_alloc_tag_set(set); | |
4506 | } | |
4507 | EXPORT_SYMBOL_GPL(blk_mq_alloc_sq_tag_set); | |
4508 | ||
24d2f903 CH |
4509 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) |
4510 | { | |
b3c661b1 | 4511 | int i, j; |
24d2f903 | 4512 | |
f7e76dbc | 4513 | for (i = 0; i < set->nr_hw_queues; i++) |
e155b0c2 | 4514 | __blk_mq_free_map_and_rqs(set, i); |
484b4061 | 4515 | |
079a2e3e JG |
4516 | if (blk_mq_is_shared_tags(set->flags)) { |
4517 | blk_mq_free_map_and_rqs(set, set->shared_tags, | |
e155b0c2 JG |
4518 | BLK_MQ_NO_HCTX_IDX); |
4519 | } | |
32bc15af | 4520 | |
b3c661b1 JA |
4521 | for (j = 0; j < set->nr_maps; j++) { |
4522 | kfree(set->map[j].mq_map); | |
4523 | set->map[j].mq_map = NULL; | |
4524 | } | |
bdd17e75 | 4525 | |
981bd189 | 4526 | kfree(set->tags); |
5676e7b6 | 4527 | set->tags = NULL; |
80bd4a7a CH |
4528 | if (set->flags & BLK_MQ_F_BLOCKING) { |
4529 | cleanup_srcu_struct(set->srcu); | |
4530 | kfree(set->srcu); | |
4531 | } | |
24d2f903 CH |
4532 | } |
4533 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
4534 | ||
e3a2b3f9 JA |
4535 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
4536 | { | |
4537 | struct blk_mq_tag_set *set = q->tag_set; | |
4538 | struct blk_mq_hw_ctx *hctx; | |
4f481208 ML |
4539 | int ret; |
4540 | unsigned long i; | |
e3a2b3f9 | 4541 | |
bd166ef1 | 4542 | if (!set) |
e3a2b3f9 JA |
4543 | return -EINVAL; |
4544 | ||
e5fa8140 AZ |
4545 | if (q->nr_requests == nr) |
4546 | return 0; | |
4547 | ||
70f36b60 | 4548 | blk_mq_freeze_queue(q); |
24f5a90f | 4549 | blk_mq_quiesce_queue(q); |
70f36b60 | 4550 | |
e3a2b3f9 JA |
4551 | ret = 0; |
4552 | queue_for_each_hw_ctx(q, hctx, i) { | |
e9137d4b KB |
4553 | if (!hctx->tags) |
4554 | continue; | |
bd166ef1 JA |
4555 | /* |
4556 | * If we're using an MQ scheduler, just update the scheduler | |
4557 | * queue depth. This is similar to what the old code would do. | |
4558 | */ | |
f6adcef5 | 4559 | if (hctx->sched_tags) { |
70f36b60 | 4560 | ret = blk_mq_tag_update_depth(hctx, &hctx->sched_tags, |
f6adcef5 | 4561 | nr, true); |
f6adcef5 JG |
4562 | } else { |
4563 | ret = blk_mq_tag_update_depth(hctx, &hctx->tags, nr, | |
4564 | false); | |
70f36b60 | 4565 | } |
e3a2b3f9 JA |
4566 | if (ret) |
4567 | break; | |
77f1e0a5 JA |
4568 | if (q->elevator && q->elevator->type->ops.depth_updated) |
4569 | q->elevator->type->ops.depth_updated(hctx); | |
e3a2b3f9 | 4570 | } |
d97e594c | 4571 | if (!ret) { |
e3a2b3f9 | 4572 | q->nr_requests = nr; |
079a2e3e | 4573 | if (blk_mq_is_shared_tags(set->flags)) { |
8fa04464 | 4574 | if (q->elevator) |
079a2e3e | 4575 | blk_mq_tag_update_sched_shared_tags(q); |
8fa04464 | 4576 | else |
079a2e3e | 4577 | blk_mq_tag_resize_shared_tags(set, nr); |
8fa04464 | 4578 | } |
d97e594c | 4579 | } |
e3a2b3f9 | 4580 | |
24f5a90f | 4581 | blk_mq_unquiesce_queue(q); |
70f36b60 | 4582 | blk_mq_unfreeze_queue(q); |
70f36b60 | 4583 | |
e3a2b3f9 JA |
4584 | return ret; |
4585 | } | |
4586 | ||
d48ece20 JW |
4587 | /* |
4588 | * request_queue and elevator_type pair. | |
4589 | * It is just used by __blk_mq_update_nr_hw_queues to cache | |
4590 | * the elevator_type associated with a request_queue. | |
4591 | */ | |
4592 | struct blk_mq_qe_pair { | |
4593 | struct list_head node; | |
4594 | struct request_queue *q; | |
4595 | struct elevator_type *type; | |
4596 | }; | |
4597 | ||
4598 | /* | |
4599 | * Cache the elevator_type in qe pair list and switch the | |
4600 | * io scheduler to 'none' | |
4601 | */ | |
4602 | static bool blk_mq_elv_switch_none(struct list_head *head, | |
4603 | struct request_queue *q) | |
4604 | { | |
4605 | struct blk_mq_qe_pair *qe; | |
4606 | ||
d48ece20 JW |
4607 | qe = kmalloc(sizeof(*qe), GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY); |
4608 | if (!qe) | |
4609 | return false; | |
4610 | ||
5fd7a84a ML |
4611 | /* q->elevator needs protection from ->sysfs_lock */ |
4612 | mutex_lock(&q->sysfs_lock); | |
4613 | ||
24516565 ML |
4614 | /* the check has to be done with holding sysfs_lock */ |
4615 | if (!q->elevator) { | |
4616 | kfree(qe); | |
4617 | goto unlock; | |
4618 | } | |
4619 | ||
d48ece20 JW |
4620 | INIT_LIST_HEAD(&qe->node); |
4621 | qe->q = q; | |
4622 | qe->type = q->elevator->type; | |
dd6f7f17 CH |
4623 | /* keep a reference to the elevator module as we'll switch back */ |
4624 | __elevator_get(qe->type); | |
d48ece20 | 4625 | list_add(&qe->node, head); |
64b36075 | 4626 | elevator_disable(q); |
24516565 | 4627 | unlock: |
d48ece20 JW |
4628 | mutex_unlock(&q->sysfs_lock); |
4629 | ||
4630 | return true; | |
4631 | } | |
4632 | ||
4a3b666e JK |
4633 | static struct blk_mq_qe_pair *blk_lookup_qe_pair(struct list_head *head, |
4634 | struct request_queue *q) | |
d48ece20 JW |
4635 | { |
4636 | struct blk_mq_qe_pair *qe; | |
d48ece20 JW |
4637 | |
4638 | list_for_each_entry(qe, head, node) | |
4a3b666e JK |
4639 | if (qe->q == q) |
4640 | return qe; | |
d48ece20 | 4641 | |
4a3b666e JK |
4642 | return NULL; |
4643 | } | |
d48ece20 | 4644 | |
4a3b666e JK |
4645 | static void blk_mq_elv_switch_back(struct list_head *head, |
4646 | struct request_queue *q) | |
4647 | { | |
4648 | struct blk_mq_qe_pair *qe; | |
4649 | struct elevator_type *t; | |
4650 | ||
4651 | qe = blk_lookup_qe_pair(head, q); | |
4652 | if (!qe) | |
4653 | return; | |
4654 | t = qe->type; | |
d48ece20 JW |
4655 | list_del(&qe->node); |
4656 | kfree(qe); | |
4657 | ||
4658 | mutex_lock(&q->sysfs_lock); | |
8237c01f | 4659 | elevator_switch(q, t); |
8ed40ee3 JC |
4660 | /* drop the reference acquired in blk_mq_elv_switch_none */ |
4661 | elevator_put(t); | |
d48ece20 JW |
4662 | mutex_unlock(&q->sysfs_lock); |
4663 | } | |
4664 | ||
e4dc2b32 KB |
4665 | static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, |
4666 | int nr_hw_queues) | |
868f2f0b KB |
4667 | { |
4668 | struct request_queue *q; | |
d48ece20 | 4669 | LIST_HEAD(head); |
e01ad46d | 4670 | int prev_nr_hw_queues; |
868f2f0b | 4671 | |
705cda97 BVA |
4672 | lockdep_assert_held(&set->tag_list_lock); |
4673 | ||
392546ae | 4674 | if (set->nr_maps == 1 && nr_hw_queues > nr_cpu_ids) |
868f2f0b | 4675 | nr_hw_queues = nr_cpu_ids; |
fe35ec58 WZ |
4676 | if (nr_hw_queues < 1) |
4677 | return; | |
4678 | if (set->nr_maps == 1 && nr_hw_queues == set->nr_hw_queues) | |
868f2f0b KB |
4679 | return; |
4680 | ||
4681 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
4682 | blk_mq_freeze_queue(q); | |
d48ece20 JW |
4683 | /* |
4684 | * Switch IO scheduler to 'none', cleaning up the data associated | |
4685 | * with the previous scheduler. We will switch back once we are done | |
4686 | * updating the new sw to hw queue mappings. | |
4687 | */ | |
4688 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
4689 | if (!blk_mq_elv_switch_none(&head, q)) | |
4690 | goto switch_back; | |
868f2f0b | 4691 | |
477e19de JW |
4692 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
4693 | blk_mq_debugfs_unregister_hctxs(q); | |
eaa870f9 | 4694 | blk_mq_sysfs_unregister_hctxs(q); |
477e19de JW |
4695 | } |
4696 | ||
a2584e43 | 4697 | prev_nr_hw_queues = set->nr_hw_queues; |
ee9d5521 | 4698 | if (blk_mq_realloc_tag_set_tags(set, nr_hw_queues) < 0) |
f7e76dbc BVA |
4699 | goto reregister; |
4700 | ||
e01ad46d | 4701 | fallback: |
aa880ad6 | 4702 | blk_mq_update_queue_map(set); |
868f2f0b KB |
4703 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
4704 | blk_mq_realloc_hw_ctxs(set, q); | |
42ee3061 | 4705 | blk_mq_update_poll_flag(q); |
e01ad46d | 4706 | if (q->nr_hw_queues != set->nr_hw_queues) { |
a846a8e6 YB |
4707 | int i = prev_nr_hw_queues; |
4708 | ||
e01ad46d JW |
4709 | pr_warn("Increasing nr_hw_queues to %d fails, fallback to %d\n", |
4710 | nr_hw_queues, prev_nr_hw_queues); | |
a846a8e6 YB |
4711 | for (; i < set->nr_hw_queues; i++) |
4712 | __blk_mq_free_map_and_rqs(set, i); | |
4713 | ||
e01ad46d | 4714 | set->nr_hw_queues = prev_nr_hw_queues; |
7d76f856 | 4715 | blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]); |
e01ad46d JW |
4716 | goto fallback; |
4717 | } | |
477e19de JW |
4718 | blk_mq_map_swqueue(q); |
4719 | } | |
4720 | ||
f7e76dbc | 4721 | reregister: |
477e19de | 4722 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
eaa870f9 | 4723 | blk_mq_sysfs_register_hctxs(q); |
477e19de | 4724 | blk_mq_debugfs_register_hctxs(q); |
868f2f0b KB |
4725 | } |
4726 | ||
d48ece20 JW |
4727 | switch_back: |
4728 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
4729 | blk_mq_elv_switch_back(&head, q); | |
4730 | ||
868f2f0b KB |
4731 | list_for_each_entry(q, &set->tag_list, tag_set_list) |
4732 | blk_mq_unfreeze_queue(q); | |
4733 | } | |
e4dc2b32 KB |
4734 | |
4735 | void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues) | |
4736 | { | |
4737 | mutex_lock(&set->tag_list_lock); | |
4738 | __blk_mq_update_nr_hw_queues(set, nr_hw_queues); | |
4739 | mutex_unlock(&set->tag_list_lock); | |
4740 | } | |
868f2f0b KB |
4741 | EXPORT_SYMBOL_GPL(blk_mq_update_nr_hw_queues); |
4742 | ||
f6c80cff KB |
4743 | static int blk_hctx_poll(struct request_queue *q, struct blk_mq_hw_ctx *hctx, |
4744 | struct io_comp_batch *iob, unsigned int flags) | |
bbd7bb70 | 4745 | { |
c6699d6f CH |
4746 | long state = get_current_state(); |
4747 | int ret; | |
bbd7bb70 | 4748 | |
aa61bec3 | 4749 | do { |
5a72e899 | 4750 | ret = q->mq_ops->poll(hctx, iob); |
bbd7bb70 | 4751 | if (ret > 0) { |
849a3700 | 4752 | __set_current_state(TASK_RUNNING); |
85f4d4b6 | 4753 | return ret; |
bbd7bb70 JA |
4754 | } |
4755 | ||
4756 | if (signal_pending_state(state, current)) | |
849a3700 | 4757 | __set_current_state(TASK_RUNNING); |
b03fbd4f | 4758 | if (task_is_running(current)) |
85f4d4b6 | 4759 | return 1; |
c6699d6f | 4760 | |
ef99b2d3 | 4761 | if (ret < 0 || (flags & BLK_POLL_ONESHOT)) |
bbd7bb70 JA |
4762 | break; |
4763 | cpu_relax(); | |
aa61bec3 | 4764 | } while (!need_resched()); |
bbd7bb70 | 4765 | |
67b4110f | 4766 | __set_current_state(TASK_RUNNING); |
85f4d4b6 | 4767 | return 0; |
bbd7bb70 | 4768 | } |
1052b8ac | 4769 | |
f6c80cff KB |
4770 | int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, |
4771 | struct io_comp_batch *iob, unsigned int flags) | |
4772 | { | |
4773 | struct blk_mq_hw_ctx *hctx = xa_load(&q->hctx_table, cookie); | |
4774 | ||
4775 | return blk_hctx_poll(q, hctx, iob, flags); | |
4776 | } | |
4777 | ||
4778 | int blk_rq_poll(struct request *rq, struct io_comp_batch *iob, | |
4779 | unsigned int poll_flags) | |
4780 | { | |
4781 | struct request_queue *q = rq->q; | |
4782 | int ret; | |
4783 | ||
4784 | if (!blk_rq_is_poll(rq)) | |
4785 | return 0; | |
4786 | if (!percpu_ref_tryget(&q->q_usage_counter)) | |
4787 | return 0; | |
4788 | ||
4789 | ret = blk_hctx_poll(q, rq->mq_hctx, iob, poll_flags); | |
4790 | blk_queue_exit(q); | |
4791 | ||
4792 | return ret; | |
4793 | } | |
4794 | EXPORT_SYMBOL_GPL(blk_rq_poll); | |
4795 | ||
9cf2bab6 JA |
4796 | unsigned int blk_mq_rq_cpu(struct request *rq) |
4797 | { | |
4798 | return rq->mq_ctx->cpu; | |
4799 | } | |
4800 | EXPORT_SYMBOL(blk_mq_rq_cpu); | |
4801 | ||
2a19b28f ML |
4802 | void blk_mq_cancel_work_sync(struct request_queue *q) |
4803 | { | |
219cf43c JC |
4804 | struct blk_mq_hw_ctx *hctx; |
4805 | unsigned long i; | |
2a19b28f | 4806 | |
219cf43c | 4807 | cancel_delayed_work_sync(&q->requeue_work); |
2a19b28f | 4808 | |
219cf43c JC |
4809 | queue_for_each_hw_ctx(q, hctx, i) |
4810 | cancel_delayed_work_sync(&hctx->run_work); | |
2a19b28f ML |
4811 | } |
4812 | ||
320ae51f JA |
4813 | static int __init blk_mq_init(void) |
4814 | { | |
c3077b5d CH |
4815 | int i; |
4816 | ||
4817 | for_each_possible_cpu(i) | |
f9ab4918 | 4818 | init_llist_head(&per_cpu(blk_cpu_done, i)); |
c3077b5d CH |
4819 | open_softirq(BLOCK_SOFTIRQ, blk_done_softirq); |
4820 | ||
4821 | cpuhp_setup_state_nocalls(CPUHP_BLOCK_SOFTIRQ_DEAD, | |
4822 | "block/softirq:dead", NULL, | |
4823 | blk_softirq_cpu_dead); | |
9467f859 TG |
4824 | cpuhp_setup_state_multi(CPUHP_BLK_MQ_DEAD, "block/mq:dead", NULL, |
4825 | blk_mq_hctx_notify_dead); | |
bf0beec0 ML |
4826 | cpuhp_setup_state_multi(CPUHP_AP_BLK_MQ_ONLINE, "block/mq:online", |
4827 | blk_mq_hctx_notify_online, | |
4828 | blk_mq_hctx_notify_offline); | |
320ae51f JA |
4829 | return 0; |
4830 | } | |
4831 | subsys_initcall(blk_mq_init); |