Commit | Line | Data |
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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 | ||
35 | #include <linux/blk-mq.h> | |
54d4e6ab | 36 | #include <linux/t10-pi.h> |
320ae51f JA |
37 | #include "blk.h" |
38 | #include "blk-mq.h" | |
9c1051aa | 39 | #include "blk-mq-debugfs.h" |
320ae51f | 40 | #include "blk-mq-tag.h" |
986d413b | 41 | #include "blk-pm.h" |
cf43e6be | 42 | #include "blk-stat.h" |
bd166ef1 | 43 | #include "blk-mq-sched.h" |
c1c80384 | 44 | #include "blk-rq-qos.h" |
82b74cac | 45 | #include "blk-ioprio.h" |
320ae51f | 46 | |
f9ab4918 | 47 | static DEFINE_PER_CPU(struct llist_head, blk_cpu_done); |
c3077b5d | 48 | |
34dbad5d OS |
49 | static void blk_mq_poll_stats_start(struct request_queue *q); |
50 | static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb); | |
51 | ||
720b8ccc SB |
52 | static int blk_mq_poll_stats_bkt(const struct request *rq) |
53 | { | |
3d244306 | 54 | int ddir, sectors, bucket; |
720b8ccc | 55 | |
99c749a4 | 56 | ddir = rq_data_dir(rq); |
3d244306 | 57 | sectors = blk_rq_stats_sectors(rq); |
720b8ccc | 58 | |
3d244306 | 59 | bucket = ddir + 2 * ilog2(sectors); |
720b8ccc SB |
60 | |
61 | if (bucket < 0) | |
62 | return -1; | |
63 | else if (bucket >= BLK_MQ_POLL_STATS_BKTS) | |
64 | return ddir + BLK_MQ_POLL_STATS_BKTS - 2; | |
65 | ||
66 | return bucket; | |
67 | } | |
68 | ||
3e08773c CH |
69 | #define BLK_QC_T_SHIFT 16 |
70 | #define BLK_QC_T_INTERNAL (1U << 31) | |
71 | ||
f70299f0 CH |
72 | static inline struct blk_mq_hw_ctx *blk_qc_to_hctx(struct request_queue *q, |
73 | blk_qc_t qc) | |
74 | { | |
4e5cc99e ML |
75 | return xa_load(&q->hctx_table, |
76 | (qc & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT); | |
f70299f0 CH |
77 | } |
78 | ||
c6699d6f CH |
79 | static inline struct request *blk_qc_to_rq(struct blk_mq_hw_ctx *hctx, |
80 | blk_qc_t qc) | |
81 | { | |
efbabbe1 CH |
82 | unsigned int tag = qc & ((1U << BLK_QC_T_SHIFT) - 1); |
83 | ||
84 | if (qc & BLK_QC_T_INTERNAL) | |
85 | return blk_mq_tag_to_rq(hctx->sched_tags, tag); | |
86 | return blk_mq_tag_to_rq(hctx->tags, tag); | |
c6699d6f CH |
87 | } |
88 | ||
3e08773c CH |
89 | static inline blk_qc_t blk_rq_to_qc(struct request *rq) |
90 | { | |
91 | return (rq->mq_hctx->queue_num << BLK_QC_T_SHIFT) | | |
92 | (rq->tag != -1 ? | |
93 | rq->tag : (rq->internal_tag | BLK_QC_T_INTERNAL)); | |
94 | } | |
95 | ||
320ae51f | 96 | /* |
85fae294 YY |
97 | * Check if any of the ctx, dispatch list or elevator |
98 | * have pending work in this hardware queue. | |
320ae51f | 99 | */ |
79f720a7 | 100 | static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx) |
320ae51f | 101 | { |
79f720a7 JA |
102 | return !list_empty_careful(&hctx->dispatch) || |
103 | sbitmap_any_bit_set(&hctx->ctx_map) || | |
bd166ef1 | 104 | blk_mq_sched_has_work(hctx); |
1429d7c9 JA |
105 | } |
106 | ||
320ae51f JA |
107 | /* |
108 | * Mark this ctx as having pending work in this hardware queue | |
109 | */ | |
110 | static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, | |
111 | struct blk_mq_ctx *ctx) | |
112 | { | |
f31967f0 JA |
113 | const int bit = ctx->index_hw[hctx->type]; |
114 | ||
115 | if (!sbitmap_test_bit(&hctx->ctx_map, bit)) | |
116 | sbitmap_set_bit(&hctx->ctx_map, bit); | |
1429d7c9 JA |
117 | } |
118 | ||
119 | static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, | |
120 | struct blk_mq_ctx *ctx) | |
121 | { | |
f31967f0 JA |
122 | const int bit = ctx->index_hw[hctx->type]; |
123 | ||
124 | sbitmap_clear_bit(&hctx->ctx_map, bit); | |
320ae51f JA |
125 | } |
126 | ||
f299b7c7 | 127 | struct mq_inflight { |
8446fe92 | 128 | struct block_device *part; |
a2e80f6f | 129 | unsigned int inflight[2]; |
f299b7c7 JA |
130 | }; |
131 | ||
2dd6532e | 132 | static bool blk_mq_check_inflight(struct request *rq, void *priv) |
f299b7c7 JA |
133 | { |
134 | struct mq_inflight *mi = priv; | |
135 | ||
b81c14ca HW |
136 | if (rq->part && blk_do_io_stat(rq) && |
137 | (!mi->part->bd_partno || rq->part == mi->part) && | |
b0d97557 | 138 | blk_mq_rq_state(rq) == MQ_RQ_IN_FLIGHT) |
bb4e6b14 | 139 | mi->inflight[rq_data_dir(rq)]++; |
7baa8572 JA |
140 | |
141 | return true; | |
f299b7c7 JA |
142 | } |
143 | ||
8446fe92 CH |
144 | unsigned int blk_mq_in_flight(struct request_queue *q, |
145 | struct block_device *part) | |
f299b7c7 | 146 | { |
a2e80f6f | 147 | struct mq_inflight mi = { .part = part }; |
f299b7c7 | 148 | |
f299b7c7 | 149 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi); |
e016b782 | 150 | |
a2e80f6f | 151 | return mi.inflight[0] + mi.inflight[1]; |
bf0ddaba OS |
152 | } |
153 | ||
8446fe92 CH |
154 | void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part, |
155 | unsigned int inflight[2]) | |
bf0ddaba | 156 | { |
a2e80f6f | 157 | struct mq_inflight mi = { .part = part }; |
bf0ddaba | 158 | |
bb4e6b14 | 159 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi); |
a2e80f6f PB |
160 | inflight[0] = mi.inflight[0]; |
161 | inflight[1] = mi.inflight[1]; | |
bf0ddaba OS |
162 | } |
163 | ||
1671d522 | 164 | void blk_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 165 | { |
7996a8b5 BL |
166 | mutex_lock(&q->mq_freeze_lock); |
167 | if (++q->mq_freeze_depth == 1) { | |
3ef28e83 | 168 | percpu_ref_kill(&q->q_usage_counter); |
7996a8b5 | 169 | mutex_unlock(&q->mq_freeze_lock); |
344e9ffc | 170 | if (queue_is_mq(q)) |
055f6e18 | 171 | blk_mq_run_hw_queues(q, false); |
7996a8b5 BL |
172 | } else { |
173 | mutex_unlock(&q->mq_freeze_lock); | |
cddd5d17 | 174 | } |
f3af020b | 175 | } |
1671d522 | 176 | EXPORT_SYMBOL_GPL(blk_freeze_queue_start); |
f3af020b | 177 | |
6bae363e | 178 | void blk_mq_freeze_queue_wait(struct request_queue *q) |
f3af020b | 179 | { |
3ef28e83 | 180 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter)); |
43a5e4e2 | 181 | } |
6bae363e | 182 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait); |
43a5e4e2 | 183 | |
f91328c4 KB |
184 | int blk_mq_freeze_queue_wait_timeout(struct request_queue *q, |
185 | unsigned long timeout) | |
186 | { | |
187 | return wait_event_timeout(q->mq_freeze_wq, | |
188 | percpu_ref_is_zero(&q->q_usage_counter), | |
189 | timeout); | |
190 | } | |
191 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait_timeout); | |
43a5e4e2 | 192 | |
f3af020b TH |
193 | /* |
194 | * Guarantee no request is in use, so we can change any data structure of | |
195 | * the queue afterward. | |
196 | */ | |
3ef28e83 | 197 | void blk_freeze_queue(struct request_queue *q) |
f3af020b | 198 | { |
3ef28e83 DW |
199 | /* |
200 | * In the !blk_mq case we are only calling this to kill the | |
201 | * q_usage_counter, otherwise this increases the freeze depth | |
202 | * and waits for it to return to zero. For this reason there is | |
203 | * no blk_unfreeze_queue(), and blk_freeze_queue() is not | |
204 | * exported to drivers as the only user for unfreeze is blk_mq. | |
205 | */ | |
1671d522 | 206 | blk_freeze_queue_start(q); |
f3af020b TH |
207 | blk_mq_freeze_queue_wait(q); |
208 | } | |
3ef28e83 DW |
209 | |
210 | void blk_mq_freeze_queue(struct request_queue *q) | |
211 | { | |
212 | /* | |
213 | * ...just an alias to keep freeze and unfreeze actions balanced | |
214 | * in the blk_mq_* namespace | |
215 | */ | |
216 | blk_freeze_queue(q); | |
217 | } | |
c761d96b | 218 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue); |
f3af020b | 219 | |
aec89dc5 | 220 | void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic) |
320ae51f | 221 | { |
7996a8b5 | 222 | mutex_lock(&q->mq_freeze_lock); |
aec89dc5 CH |
223 | if (force_atomic) |
224 | q->q_usage_counter.data->force_atomic = true; | |
7996a8b5 BL |
225 | q->mq_freeze_depth--; |
226 | WARN_ON_ONCE(q->mq_freeze_depth < 0); | |
227 | if (!q->mq_freeze_depth) { | |
bdd63160 | 228 | percpu_ref_resurrect(&q->q_usage_counter); |
320ae51f | 229 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 230 | } |
7996a8b5 | 231 | mutex_unlock(&q->mq_freeze_lock); |
320ae51f | 232 | } |
aec89dc5 CH |
233 | |
234 | void blk_mq_unfreeze_queue(struct request_queue *q) | |
235 | { | |
236 | __blk_mq_unfreeze_queue(q, false); | |
237 | } | |
b4c6a028 | 238 | EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
320ae51f | 239 | |
852ec809 BVA |
240 | /* |
241 | * FIXME: replace the scsi_internal_device_*block_nowait() calls in the | |
242 | * mpt3sas driver such that this function can be removed. | |
243 | */ | |
244 | void blk_mq_quiesce_queue_nowait(struct request_queue *q) | |
245 | { | |
e70feb8b ML |
246 | unsigned long flags; |
247 | ||
248 | spin_lock_irqsave(&q->queue_lock, flags); | |
249 | if (!q->quiesce_depth++) | |
250 | blk_queue_flag_set(QUEUE_FLAG_QUIESCED, q); | |
251 | spin_unlock_irqrestore(&q->queue_lock, flags); | |
852ec809 BVA |
252 | } |
253 | EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue_nowait); | |
254 | ||
6a83e74d | 255 | /** |
9ef4d020 | 256 | * blk_mq_wait_quiesce_done() - wait until in-progress quiesce is done |
6a83e74d BVA |
257 | * @q: request queue. |
258 | * | |
9ef4d020 ML |
259 | * Note: it is driver's responsibility for making sure that quiesce has |
260 | * been started. | |
6a83e74d | 261 | */ |
9ef4d020 | 262 | void blk_mq_wait_quiesce_done(struct request_queue *q) |
6a83e74d | 263 | { |
704b914f ML |
264 | if (blk_queue_has_srcu(q)) |
265 | synchronize_srcu(q->srcu); | |
266 | else | |
6a83e74d BVA |
267 | synchronize_rcu(); |
268 | } | |
9ef4d020 ML |
269 | EXPORT_SYMBOL_GPL(blk_mq_wait_quiesce_done); |
270 | ||
271 | /** | |
272 | * blk_mq_quiesce_queue() - wait until all ongoing dispatches have finished | |
273 | * @q: request queue. | |
274 | * | |
275 | * Note: this function does not prevent that the struct request end_io() | |
276 | * callback function is invoked. Once this function is returned, we make | |
277 | * sure no dispatch can happen until the queue is unquiesced via | |
278 | * blk_mq_unquiesce_queue(). | |
279 | */ | |
280 | void blk_mq_quiesce_queue(struct request_queue *q) | |
281 | { | |
282 | blk_mq_quiesce_queue_nowait(q); | |
283 | blk_mq_wait_quiesce_done(q); | |
284 | } | |
6a83e74d BVA |
285 | EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue); |
286 | ||
e4e73913 ML |
287 | /* |
288 | * blk_mq_unquiesce_queue() - counterpart of blk_mq_quiesce_queue() | |
289 | * @q: request queue. | |
290 | * | |
291 | * This function recovers queue into the state before quiescing | |
292 | * which is done by blk_mq_quiesce_queue. | |
293 | */ | |
294 | void blk_mq_unquiesce_queue(struct request_queue *q) | |
295 | { | |
e70feb8b ML |
296 | unsigned long flags; |
297 | bool run_queue = false; | |
298 | ||
299 | spin_lock_irqsave(&q->queue_lock, flags); | |
300 | if (WARN_ON_ONCE(q->quiesce_depth <= 0)) { | |
301 | ; | |
302 | } else if (!--q->quiesce_depth) { | |
303 | blk_queue_flag_clear(QUEUE_FLAG_QUIESCED, q); | |
304 | run_queue = true; | |
305 | } | |
306 | spin_unlock_irqrestore(&q->queue_lock, flags); | |
f4560ffe | 307 | |
1d9e9bc6 | 308 | /* dispatch requests which are inserted during quiescing */ |
e70feb8b ML |
309 | if (run_queue) |
310 | blk_mq_run_hw_queues(q, true); | |
e4e73913 ML |
311 | } |
312 | EXPORT_SYMBOL_GPL(blk_mq_unquiesce_queue); | |
313 | ||
aed3ea94 JA |
314 | void blk_mq_wake_waiters(struct request_queue *q) |
315 | { | |
316 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 317 | unsigned long i; |
aed3ea94 JA |
318 | |
319 | queue_for_each_hw_ctx(q, hctx, i) | |
320 | if (blk_mq_hw_queue_mapped(hctx)) | |
321 | blk_mq_tag_wakeup_all(hctx->tags, true); | |
322 | } | |
323 | ||
52fdbbcc CH |
324 | void blk_rq_init(struct request_queue *q, struct request *rq) |
325 | { | |
326 | memset(rq, 0, sizeof(*rq)); | |
327 | ||
328 | INIT_LIST_HEAD(&rq->queuelist); | |
329 | rq->q = q; | |
330 | rq->__sector = (sector_t) -1; | |
331 | INIT_HLIST_NODE(&rq->hash); | |
332 | RB_CLEAR_NODE(&rq->rb_node); | |
333 | rq->tag = BLK_MQ_NO_TAG; | |
334 | rq->internal_tag = BLK_MQ_NO_TAG; | |
335 | rq->start_time_ns = ktime_get_ns(); | |
336 | rq->part = NULL; | |
337 | blk_crypto_rq_set_defaults(rq); | |
338 | } | |
339 | EXPORT_SYMBOL(blk_rq_init); | |
340 | ||
e4cdf1a1 | 341 | static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, |
fe6134f6 | 342 | struct blk_mq_tags *tags, unsigned int tag, u64 alloc_time_ns) |
320ae51f | 343 | { |
605f784e PB |
344 | struct blk_mq_ctx *ctx = data->ctx; |
345 | struct blk_mq_hw_ctx *hctx = data->hctx; | |
346 | struct request_queue *q = data->q; | |
e4cdf1a1 | 347 | struct request *rq = tags->static_rqs[tag]; |
c3a148d2 | 348 | |
c7b84d42 JA |
349 | rq->q = q; |
350 | rq->mq_ctx = ctx; | |
351 | rq->mq_hctx = hctx; | |
352 | rq->cmd_flags = data->cmd_flags; | |
353 | ||
354 | if (data->flags & BLK_MQ_REQ_PM) | |
355 | data->rq_flags |= RQF_PM; | |
356 | if (blk_queue_io_stat(q)) | |
357 | data->rq_flags |= RQF_IO_STAT; | |
358 | rq->rq_flags = data->rq_flags; | |
359 | ||
56f8da64 | 360 | if (!(data->rq_flags & RQF_ELV)) { |
e4cdf1a1 | 361 | rq->tag = tag; |
76647368 | 362 | rq->internal_tag = BLK_MQ_NO_TAG; |
56f8da64 JA |
363 | } else { |
364 | rq->tag = BLK_MQ_NO_TAG; | |
365 | rq->internal_tag = tag; | |
e4cdf1a1 | 366 | } |
c7b84d42 | 367 | rq->timeout = 0; |
e4cdf1a1 | 368 | |
4f266f2b PB |
369 | if (blk_mq_need_time_stamp(rq)) |
370 | rq->start_time_ns = ktime_get_ns(); | |
371 | else | |
372 | rq->start_time_ns = 0; | |
af76e555 | 373 | rq->part = NULL; |
6f816b4b TH |
374 | #ifdef CONFIG_BLK_RQ_ALLOC_TIME |
375 | rq->alloc_time_ns = alloc_time_ns; | |
376 | #endif | |
544ccc8d | 377 | rq->io_start_time_ns = 0; |
3d244306 | 378 | rq->stats_sectors = 0; |
af76e555 CH |
379 | rq->nr_phys_segments = 0; |
380 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
381 | rq->nr_integrity_segments = 0; | |
382 | #endif | |
af76e555 CH |
383 | rq->end_io = NULL; |
384 | rq->end_io_data = NULL; | |
af76e555 | 385 | |
4f266f2b PB |
386 | blk_crypto_rq_set_defaults(rq); |
387 | INIT_LIST_HEAD(&rq->queuelist); | |
388 | /* tag was already set */ | |
389 | WRITE_ONCE(rq->deadline, 0); | |
0a467d0f | 390 | req_ref_set(rq, 1); |
7ea4d8a4 | 391 | |
4f266f2b | 392 | if (rq->rq_flags & RQF_ELV) { |
7ea4d8a4 CH |
393 | struct elevator_queue *e = data->q->elevator; |
394 | ||
4f266f2b PB |
395 | INIT_HLIST_NODE(&rq->hash); |
396 | RB_CLEAR_NODE(&rq->rb_node); | |
397 | ||
398 | if (!op_is_flush(data->cmd_flags) && | |
399 | e->type->ops.prepare_request) { | |
7ea4d8a4 CH |
400 | e->type->ops.prepare_request(rq); |
401 | rq->rq_flags |= RQF_ELVPRIV; | |
402 | } | |
403 | } | |
404 | ||
e4cdf1a1 | 405 | return rq; |
5dee8577 CH |
406 | } |
407 | ||
349302da JA |
408 | static inline struct request * |
409 | __blk_mq_alloc_requests_batch(struct blk_mq_alloc_data *data, | |
410 | u64 alloc_time_ns) | |
411 | { | |
412 | unsigned int tag, tag_offset; | |
fe6134f6 | 413 | struct blk_mq_tags *tags; |
349302da | 414 | struct request *rq; |
fe6134f6 | 415 | unsigned long tag_mask; |
349302da JA |
416 | int i, nr = 0; |
417 | ||
fe6134f6 JA |
418 | tag_mask = blk_mq_get_tags(data, data->nr_tags, &tag_offset); |
419 | if (unlikely(!tag_mask)) | |
349302da JA |
420 | return NULL; |
421 | ||
fe6134f6 JA |
422 | tags = blk_mq_tags_from_data(data); |
423 | for (i = 0; tag_mask; i++) { | |
424 | if (!(tag_mask & (1UL << i))) | |
349302da JA |
425 | continue; |
426 | tag = tag_offset + i; | |
a22c00be | 427 | prefetch(tags->static_rqs[tag]); |
fe6134f6 JA |
428 | tag_mask &= ~(1UL << i); |
429 | rq = blk_mq_rq_ctx_init(data, tags, tag, alloc_time_ns); | |
013a7f95 | 430 | rq_list_add(data->cached_rq, rq); |
c5fc7b93 | 431 | nr++; |
349302da | 432 | } |
c5fc7b93 JA |
433 | /* caller already holds a reference, add for remainder */ |
434 | percpu_ref_get_many(&data->q->q_usage_counter, nr - 1); | |
349302da JA |
435 | data->nr_tags -= nr; |
436 | ||
013a7f95 | 437 | return rq_list_pop(data->cached_rq); |
349302da JA |
438 | } |
439 | ||
b90cfaed | 440 | static struct request *__blk_mq_alloc_requests(struct blk_mq_alloc_data *data) |
d2c0d383 | 441 | { |
e6e7abff | 442 | struct request_queue *q = data->q; |
6f816b4b | 443 | u64 alloc_time_ns = 0; |
47c122e3 | 444 | struct request *rq; |
600c3b0c | 445 | unsigned int tag; |
d2c0d383 | 446 | |
6f816b4b TH |
447 | /* alloc_time includes depth and tag waits */ |
448 | if (blk_queue_rq_alloc_time(q)) | |
449 | alloc_time_ns = ktime_get_ns(); | |
450 | ||
f9afca4d | 451 | if (data->cmd_flags & REQ_NOWAIT) |
03a07c92 | 452 | data->flags |= BLK_MQ_REQ_NOWAIT; |
d2c0d383 | 453 | |
781dd830 JA |
454 | if (q->elevator) { |
455 | struct elevator_queue *e = q->elevator; | |
456 | ||
457 | data->rq_flags |= RQF_ELV; | |
458 | ||
d2c0d383 | 459 | /* |
8d663f34 | 460 | * Flush/passthrough requests are special and go directly to the |
17a51199 JA |
461 | * dispatch list. Don't include reserved tags in the |
462 | * limiting, as it isn't useful. | |
d2c0d383 | 463 | */ |
f9afca4d | 464 | if (!op_is_flush(data->cmd_flags) && |
8d663f34 | 465 | !blk_op_is_passthrough(data->cmd_flags) && |
f9afca4d | 466 | e->type->ops.limit_depth && |
17a51199 | 467 | !(data->flags & BLK_MQ_REQ_RESERVED)) |
f9afca4d | 468 | e->type->ops.limit_depth(data->cmd_flags, data); |
d2c0d383 CH |
469 | } |
470 | ||
bf0beec0 | 471 | retry: |
600c3b0c CH |
472 | data->ctx = blk_mq_get_ctx(q); |
473 | data->hctx = blk_mq_map_queue(q, data->cmd_flags, data->ctx); | |
781dd830 | 474 | if (!(data->rq_flags & RQF_ELV)) |
600c3b0c CH |
475 | blk_mq_tag_busy(data->hctx); |
476 | ||
99e48cd6 JG |
477 | if (data->flags & BLK_MQ_REQ_RESERVED) |
478 | data->rq_flags |= RQF_RESV; | |
479 | ||
349302da JA |
480 | /* |
481 | * Try batched alloc if we want more than 1 tag. | |
482 | */ | |
483 | if (data->nr_tags > 1) { | |
484 | rq = __blk_mq_alloc_requests_batch(data, alloc_time_ns); | |
485 | if (rq) | |
486 | return rq; | |
487 | data->nr_tags = 1; | |
488 | } | |
489 | ||
bf0beec0 ML |
490 | /* |
491 | * Waiting allocations only fail because of an inactive hctx. In that | |
492 | * case just retry the hctx assignment and tag allocation as CPU hotplug | |
493 | * should have migrated us to an online CPU by now. | |
494 | */ | |
e4cdf1a1 | 495 | tag = blk_mq_get_tag(data); |
bf0beec0 ML |
496 | if (tag == BLK_MQ_NO_TAG) { |
497 | if (data->flags & BLK_MQ_REQ_NOWAIT) | |
498 | return NULL; | |
bf0beec0 | 499 | /* |
349302da JA |
500 | * Give up the CPU and sleep for a random short time to |
501 | * ensure that thread using a realtime scheduling class | |
502 | * are migrated off the CPU, and thus off the hctx that | |
503 | * is going away. | |
bf0beec0 ML |
504 | */ |
505 | msleep(3); | |
506 | goto retry; | |
507 | } | |
47c122e3 | 508 | |
fe6134f6 JA |
509 | return blk_mq_rq_ctx_init(data, blk_mq_tags_from_data(data), tag, |
510 | alloc_time_ns); | |
d2c0d383 CH |
511 | } |
512 | ||
4b6a5d9c JA |
513 | static struct request *blk_mq_rq_cache_fill(struct request_queue *q, |
514 | struct blk_plug *plug, | |
515 | blk_opf_t opf, | |
516 | blk_mq_req_flags_t flags) | |
320ae51f | 517 | { |
e6e7abff CH |
518 | struct blk_mq_alloc_data data = { |
519 | .q = q, | |
520 | .flags = flags, | |
16458cf3 | 521 | .cmd_flags = opf, |
4b6a5d9c JA |
522 | .nr_tags = plug->nr_ios, |
523 | .cached_rq = &plug->cached_rq, | |
e6e7abff | 524 | }; |
bd166ef1 | 525 | struct request *rq; |
320ae51f | 526 | |
4b6a5d9c JA |
527 | if (blk_queue_enter(q, flags)) |
528 | return NULL; | |
529 | ||
530 | plug->nr_ios = 1; | |
320ae51f | 531 | |
b90cfaed | 532 | rq = __blk_mq_alloc_requests(&data); |
4b6a5d9c JA |
533 | if (unlikely(!rq)) |
534 | blk_queue_exit(q); | |
535 | return rq; | |
536 | } | |
537 | ||
538 | static struct request *blk_mq_alloc_cached_request(struct request_queue *q, | |
539 | blk_opf_t opf, | |
540 | blk_mq_req_flags_t flags) | |
541 | { | |
542 | struct blk_plug *plug = current->plug; | |
543 | struct request *rq; | |
544 | ||
545 | if (!plug) | |
546 | return NULL; | |
547 | if (rq_list_empty(plug->cached_rq)) { | |
548 | if (plug->nr_ios == 1) | |
549 | return NULL; | |
550 | rq = blk_mq_rq_cache_fill(q, plug, opf, flags); | |
551 | if (rq) | |
552 | goto got_it; | |
553 | return NULL; | |
554 | } | |
555 | rq = rq_list_peek(&plug->cached_rq); | |
556 | if (!rq || rq->q != q) | |
557 | return NULL; | |
558 | ||
559 | if (blk_mq_get_hctx_type(opf) != rq->mq_hctx->type) | |
560 | return NULL; | |
561 | if (op_is_flush(rq->cmd_flags) != op_is_flush(opf)) | |
562 | return NULL; | |
563 | ||
564 | plug->cached_rq = rq_list_next(rq); | |
565 | got_it: | |
566 | rq->cmd_flags = opf; | |
567 | INIT_LIST_HEAD(&rq->queuelist); | |
568 | return rq; | |
569 | } | |
570 | ||
571 | struct request *blk_mq_alloc_request(struct request_queue *q, blk_opf_t opf, | |
572 | blk_mq_req_flags_t flags) | |
573 | { | |
574 | struct request *rq; | |
575 | ||
576 | rq = blk_mq_alloc_cached_request(q, opf, flags); | |
577 | if (!rq) { | |
578 | struct blk_mq_alloc_data data = { | |
579 | .q = q, | |
580 | .flags = flags, | |
581 | .cmd_flags = opf, | |
582 | .nr_tags = 1, | |
583 | }; | |
584 | int ret; | |
585 | ||
586 | ret = blk_queue_enter(q, flags); | |
587 | if (ret) | |
588 | return ERR_PTR(ret); | |
589 | ||
590 | rq = __blk_mq_alloc_requests(&data); | |
591 | if (!rq) | |
592 | goto out_queue_exit; | |
593 | } | |
0c4de0f3 CH |
594 | rq->__data_len = 0; |
595 | rq->__sector = (sector_t) -1; | |
596 | rq->bio = rq->biotail = NULL; | |
320ae51f | 597 | return rq; |
a5ea5811 CH |
598 | out_queue_exit: |
599 | blk_queue_exit(q); | |
600 | return ERR_PTR(-EWOULDBLOCK); | |
320ae51f | 601 | } |
4bb659b1 | 602 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 603 | |
cd6ce148 | 604 | struct request *blk_mq_alloc_request_hctx(struct request_queue *q, |
16458cf3 | 605 | blk_opf_t opf, blk_mq_req_flags_t flags, unsigned int hctx_idx) |
1f5bd336 | 606 | { |
e6e7abff CH |
607 | struct blk_mq_alloc_data data = { |
608 | .q = q, | |
609 | .flags = flags, | |
16458cf3 | 610 | .cmd_flags = opf, |
47c122e3 | 611 | .nr_tags = 1, |
e6e7abff | 612 | }; |
600c3b0c | 613 | u64 alloc_time_ns = 0; |
e3c5a78c | 614 | struct request *rq; |
6d2809d5 | 615 | unsigned int cpu; |
600c3b0c | 616 | unsigned int tag; |
1f5bd336 ML |
617 | int ret; |
618 | ||
600c3b0c CH |
619 | /* alloc_time includes depth and tag waits */ |
620 | if (blk_queue_rq_alloc_time(q)) | |
621 | alloc_time_ns = ktime_get_ns(); | |
622 | ||
1f5bd336 ML |
623 | /* |
624 | * If the tag allocator sleeps we could get an allocation for a | |
625 | * different hardware context. No need to complicate the low level | |
626 | * allocator for this for the rare use case of a command tied to | |
627 | * a specific queue. | |
628 | */ | |
600c3b0c | 629 | if (WARN_ON_ONCE(!(flags & (BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED)))) |
1f5bd336 ML |
630 | return ERR_PTR(-EINVAL); |
631 | ||
632 | if (hctx_idx >= q->nr_hw_queues) | |
633 | return ERR_PTR(-EIO); | |
634 | ||
3a0a5299 | 635 | ret = blk_queue_enter(q, flags); |
1f5bd336 ML |
636 | if (ret) |
637 | return ERR_PTR(ret); | |
638 | ||
c8712c6a CH |
639 | /* |
640 | * Check if the hardware context is actually mapped to anything. | |
641 | * If not tell the caller that it should skip this queue. | |
642 | */ | |
a5ea5811 | 643 | ret = -EXDEV; |
4e5cc99e | 644 | data.hctx = xa_load(&q->hctx_table, hctx_idx); |
e6e7abff | 645 | if (!blk_mq_hw_queue_mapped(data.hctx)) |
a5ea5811 | 646 | goto out_queue_exit; |
e6e7abff | 647 | cpu = cpumask_first_and(data.hctx->cpumask, cpu_online_mask); |
14dc7a18 BVA |
648 | if (cpu >= nr_cpu_ids) |
649 | goto out_queue_exit; | |
e6e7abff | 650 | data.ctx = __blk_mq_get_ctx(q, cpu); |
1f5bd336 | 651 | |
42fdc5e4 | 652 | if (!q->elevator) |
600c3b0c | 653 | blk_mq_tag_busy(data.hctx); |
781dd830 JA |
654 | else |
655 | data.rq_flags |= RQF_ELV; | |
600c3b0c | 656 | |
99e48cd6 JG |
657 | if (flags & BLK_MQ_REQ_RESERVED) |
658 | data.rq_flags |= RQF_RESV; | |
659 | ||
a5ea5811 | 660 | ret = -EWOULDBLOCK; |
600c3b0c CH |
661 | tag = blk_mq_get_tag(&data); |
662 | if (tag == BLK_MQ_NO_TAG) | |
a5ea5811 | 663 | goto out_queue_exit; |
e3c5a78c | 664 | rq = blk_mq_rq_ctx_init(&data, blk_mq_tags_from_data(&data), tag, |
fe6134f6 | 665 | alloc_time_ns); |
e3c5a78c JG |
666 | rq->__data_len = 0; |
667 | rq->__sector = (sector_t) -1; | |
668 | rq->bio = rq->biotail = NULL; | |
669 | return rq; | |
600c3b0c | 670 | |
a5ea5811 CH |
671 | out_queue_exit: |
672 | blk_queue_exit(q); | |
673 | return ERR_PTR(ret); | |
1f5bd336 ML |
674 | } |
675 | EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx); | |
676 | ||
12f5b931 KB |
677 | static void __blk_mq_free_request(struct request *rq) |
678 | { | |
679 | struct request_queue *q = rq->q; | |
680 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
ea4f995e | 681 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
12f5b931 KB |
682 | const int sched_tag = rq->internal_tag; |
683 | ||
a892c8d5 | 684 | blk_crypto_free_request(rq); |
986d413b | 685 | blk_pm_mark_last_busy(rq); |
ea4f995e | 686 | rq->mq_hctx = NULL; |
76647368 | 687 | if (rq->tag != BLK_MQ_NO_TAG) |
cae740a0 | 688 | blk_mq_put_tag(hctx->tags, ctx, rq->tag); |
76647368 | 689 | if (sched_tag != BLK_MQ_NO_TAG) |
cae740a0 | 690 | blk_mq_put_tag(hctx->sched_tags, ctx, sched_tag); |
12f5b931 KB |
691 | blk_mq_sched_restart(hctx); |
692 | blk_queue_exit(q); | |
693 | } | |
694 | ||
6af54051 | 695 | void blk_mq_free_request(struct request *rq) |
320ae51f | 696 | { |
320ae51f | 697 | struct request_queue *q = rq->q; |
ea4f995e | 698 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
6af54051 | 699 | |
222ee581 CH |
700 | if ((rq->rq_flags & RQF_ELVPRIV) && |
701 | q->elevator->type->ops.finish_request) | |
702 | q->elevator->type->ops.finish_request(rq); | |
320ae51f | 703 | |
e8064021 | 704 | if (rq->rq_flags & RQF_MQ_INFLIGHT) |
bccf5e26 | 705 | __blk_mq_dec_active_requests(hctx); |
87760e5e | 706 | |
7beb2f84 | 707 | if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq))) |
d152c682 | 708 | laptop_io_completion(q->disk->bdi); |
7beb2f84 | 709 | |
a7905043 | 710 | rq_qos_done(q, rq); |
0d2602ca | 711 | |
12f5b931 | 712 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); |
0a467d0f | 713 | if (req_ref_put_and_test(rq)) |
12f5b931 | 714 | __blk_mq_free_request(rq); |
320ae51f | 715 | } |
1a3b595a | 716 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 717 | |
47c122e3 | 718 | void blk_mq_free_plug_rqs(struct blk_plug *plug) |
320ae51f | 719 | { |
013a7f95 | 720 | struct request *rq; |
fe1f4526 | 721 | |
c5fc7b93 | 722 | while ((rq = rq_list_pop(&plug->cached_rq)) != NULL) |
47c122e3 | 723 | blk_mq_free_request(rq); |
47c122e3 | 724 | } |
522a7775 | 725 | |
22350ad7 CH |
726 | void blk_dump_rq_flags(struct request *rq, char *msg) |
727 | { | |
728 | printk(KERN_INFO "%s: dev %s: flags=%llx\n", msg, | |
f3fa33ac | 729 | rq->q->disk ? rq->q->disk->disk_name : "?", |
16458cf3 | 730 | (__force unsigned long long) rq->cmd_flags); |
22350ad7 CH |
731 | |
732 | printk(KERN_INFO " sector %llu, nr/cnr %u/%u\n", | |
733 | (unsigned long long)blk_rq_pos(rq), | |
734 | blk_rq_sectors(rq), blk_rq_cur_sectors(rq)); | |
735 | printk(KERN_INFO " bio %p, biotail %p, len %u\n", | |
736 | rq->bio, rq->biotail, blk_rq_bytes(rq)); | |
737 | } | |
738 | EXPORT_SYMBOL(blk_dump_rq_flags); | |
739 | ||
9be3e06f JA |
740 | static void req_bio_endio(struct request *rq, struct bio *bio, |
741 | unsigned int nbytes, blk_status_t error) | |
742 | { | |
478eb72b | 743 | if (unlikely(error)) { |
9be3e06f | 744 | bio->bi_status = error; |
478eb72b | 745 | } else if (req_op(rq) == REQ_OP_ZONE_APPEND) { |
9be3e06f JA |
746 | /* |
747 | * Partial zone append completions cannot be supported as the | |
748 | * BIO fragments may end up not being written sequentially. | |
749 | */ | |
297db731 | 750 | if (bio->bi_iter.bi_size != nbytes) |
9be3e06f JA |
751 | bio->bi_status = BLK_STS_IOERR; |
752 | else | |
753 | bio->bi_iter.bi_sector = rq->__sector; | |
754 | } | |
755 | ||
478eb72b PB |
756 | bio_advance(bio, nbytes); |
757 | ||
758 | if (unlikely(rq->rq_flags & RQF_QUIET)) | |
759 | bio_set_flag(bio, BIO_QUIET); | |
9be3e06f JA |
760 | /* don't actually finish bio if it's part of flush sequence */ |
761 | if (bio->bi_iter.bi_size == 0 && !(rq->rq_flags & RQF_FLUSH_SEQ)) | |
762 | bio_endio(bio); | |
763 | } | |
764 | ||
765 | static void blk_account_io_completion(struct request *req, unsigned int bytes) | |
766 | { | |
767 | if (req->part && blk_do_io_stat(req)) { | |
768 | const int sgrp = op_stat_group(req_op(req)); | |
769 | ||
770 | part_stat_lock(); | |
771 | part_stat_add(req->part, sectors[sgrp], bytes >> 9); | |
772 | part_stat_unlock(); | |
773 | } | |
774 | } | |
775 | ||
0d7a29a2 CH |
776 | static void blk_print_req_error(struct request *req, blk_status_t status) |
777 | { | |
778 | printk_ratelimited(KERN_ERR | |
779 | "%s error, dev %s, sector %llu op 0x%x:(%s) flags 0x%x " | |
780 | "phys_seg %u prio class %u\n", | |
781 | blk_status_to_str(status), | |
f3fa33ac | 782 | req->q->disk ? req->q->disk->disk_name : "?", |
16458cf3 BVA |
783 | blk_rq_pos(req), (__force u32)req_op(req), |
784 | blk_op_str(req_op(req)), | |
785 | (__force u32)(req->cmd_flags & ~REQ_OP_MASK), | |
0d7a29a2 CH |
786 | req->nr_phys_segments, |
787 | IOPRIO_PRIO_CLASS(req->ioprio)); | |
788 | } | |
789 | ||
5581a5dd JA |
790 | /* |
791 | * Fully end IO on a request. Does not support partial completions, or | |
792 | * errors. | |
793 | */ | |
794 | static void blk_complete_request(struct request *req) | |
795 | { | |
796 | const bool is_flush = (req->rq_flags & RQF_FLUSH_SEQ) != 0; | |
797 | int total_bytes = blk_rq_bytes(req); | |
798 | struct bio *bio = req->bio; | |
799 | ||
800 | trace_block_rq_complete(req, BLK_STS_OK, total_bytes); | |
801 | ||
802 | if (!bio) | |
803 | return; | |
804 | ||
805 | #ifdef CONFIG_BLK_DEV_INTEGRITY | |
806 | if (blk_integrity_rq(req) && req_op(req) == REQ_OP_READ) | |
807 | req->q->integrity.profile->complete_fn(req, total_bytes); | |
808 | #endif | |
809 | ||
810 | blk_account_io_completion(req, total_bytes); | |
811 | ||
812 | do { | |
813 | struct bio *next = bio->bi_next; | |
814 | ||
815 | /* Completion has already been traced */ | |
816 | bio_clear_flag(bio, BIO_TRACE_COMPLETION); | |
a12821d5 PR |
817 | |
818 | if (req_op(req) == REQ_OP_ZONE_APPEND) | |
819 | bio->bi_iter.bi_sector = req->__sector; | |
820 | ||
5581a5dd JA |
821 | if (!is_flush) |
822 | bio_endio(bio); | |
823 | bio = next; | |
824 | } while (bio); | |
825 | ||
826 | /* | |
827 | * Reset counters so that the request stacking driver | |
828 | * can find how many bytes remain in the request | |
829 | * later. | |
830 | */ | |
ab3e1d3b JA |
831 | if (!req->end_io) { |
832 | req->bio = NULL; | |
833 | req->__data_len = 0; | |
834 | } | |
5581a5dd JA |
835 | } |
836 | ||
9be3e06f JA |
837 | /** |
838 | * blk_update_request - Complete multiple bytes without completing the request | |
839 | * @req: the request being processed | |
840 | * @error: block status code | |
841 | * @nr_bytes: number of bytes to complete for @req | |
842 | * | |
843 | * Description: | |
844 | * Ends I/O on a number of bytes attached to @req, but doesn't complete | |
845 | * the request structure even if @req doesn't have leftover. | |
846 | * If @req has leftover, sets it up for the next range of segments. | |
847 | * | |
848 | * Passing the result of blk_rq_bytes() as @nr_bytes guarantees | |
849 | * %false return from this function. | |
850 | * | |
851 | * Note: | |
852 | * The RQF_SPECIAL_PAYLOAD flag is ignored on purpose in this function | |
853 | * except in the consistency check at the end of this function. | |
854 | * | |
855 | * Return: | |
856 | * %false - this request doesn't have any more data | |
857 | * %true - this request has more data | |
858 | **/ | |
859 | bool blk_update_request(struct request *req, blk_status_t error, | |
860 | unsigned int nr_bytes) | |
861 | { | |
862 | int total_bytes; | |
863 | ||
8a7d267b | 864 | trace_block_rq_complete(req, error, nr_bytes); |
9be3e06f JA |
865 | |
866 | if (!req->bio) | |
867 | return false; | |
868 | ||
869 | #ifdef CONFIG_BLK_DEV_INTEGRITY | |
870 | if (blk_integrity_rq(req) && req_op(req) == REQ_OP_READ && | |
871 | error == BLK_STS_OK) | |
872 | req->q->integrity.profile->complete_fn(req, nr_bytes); | |
873 | #endif | |
874 | ||
875 | if (unlikely(error && !blk_rq_is_passthrough(req) && | |
3d973a76 CH |
876 | !(req->rq_flags & RQF_QUIET)) && |
877 | !test_bit(GD_DEAD, &req->q->disk->state)) { | |
9be3e06f | 878 | blk_print_req_error(req, error); |
d5869fdc YS |
879 | trace_block_rq_error(req, error, nr_bytes); |
880 | } | |
9be3e06f JA |
881 | |
882 | blk_account_io_completion(req, nr_bytes); | |
883 | ||
884 | total_bytes = 0; | |
885 | while (req->bio) { | |
886 | struct bio *bio = req->bio; | |
887 | unsigned bio_bytes = min(bio->bi_iter.bi_size, nr_bytes); | |
888 | ||
889 | if (bio_bytes == bio->bi_iter.bi_size) | |
890 | req->bio = bio->bi_next; | |
891 | ||
892 | /* Completion has already been traced */ | |
893 | bio_clear_flag(bio, BIO_TRACE_COMPLETION); | |
894 | req_bio_endio(req, bio, bio_bytes, error); | |
895 | ||
896 | total_bytes += bio_bytes; | |
897 | nr_bytes -= bio_bytes; | |
898 | ||
899 | if (!nr_bytes) | |
900 | break; | |
901 | } | |
902 | ||
903 | /* | |
904 | * completely done | |
905 | */ | |
906 | if (!req->bio) { | |
907 | /* | |
908 | * Reset counters so that the request stacking driver | |
909 | * can find how many bytes remain in the request | |
910 | * later. | |
911 | */ | |
912 | req->__data_len = 0; | |
913 | return false; | |
914 | } | |
915 | ||
916 | req->__data_len -= total_bytes; | |
917 | ||
918 | /* update sector only for requests with clear definition of sector */ | |
919 | if (!blk_rq_is_passthrough(req)) | |
920 | req->__sector += total_bytes >> 9; | |
921 | ||
922 | /* mixed attributes always follow the first bio */ | |
923 | if (req->rq_flags & RQF_MIXED_MERGE) { | |
924 | req->cmd_flags &= ~REQ_FAILFAST_MASK; | |
925 | req->cmd_flags |= req->bio->bi_opf & REQ_FAILFAST_MASK; | |
926 | } | |
927 | ||
928 | if (!(req->rq_flags & RQF_SPECIAL_PAYLOAD)) { | |
929 | /* | |
930 | * If total number of sectors is less than the first segment | |
931 | * size, something has gone terribly wrong. | |
932 | */ | |
933 | if (blk_rq_bytes(req) < blk_rq_cur_bytes(req)) { | |
934 | blk_dump_rq_flags(req, "request botched"); | |
935 | req->__data_len = blk_rq_cur_bytes(req); | |
936 | } | |
937 | ||
938 | /* recalculate the number of segments */ | |
939 | req->nr_phys_segments = blk_recalc_rq_segments(req); | |
940 | } | |
941 | ||
942 | return true; | |
943 | } | |
944 | EXPORT_SYMBOL_GPL(blk_update_request); | |
945 | ||
450b7879 CH |
946 | static void __blk_account_io_done(struct request *req, u64 now) |
947 | { | |
948 | const int sgrp = op_stat_group(req_op(req)); | |
949 | ||
950 | part_stat_lock(); | |
951 | update_io_ticks(req->part, jiffies, true); | |
952 | part_stat_inc(req->part, ios[sgrp]); | |
953 | part_stat_add(req->part, nsecs[sgrp], now - req->start_time_ns); | |
954 | part_stat_unlock(); | |
955 | } | |
956 | ||
957 | static inline void blk_account_io_done(struct request *req, u64 now) | |
958 | { | |
959 | /* | |
960 | * Account IO completion. flush_rq isn't accounted as a | |
961 | * normal IO on queueing nor completion. Accounting the | |
962 | * containing request is enough. | |
963 | */ | |
964 | if (blk_do_io_stat(req) && req->part && | |
965 | !(req->rq_flags & RQF_FLUSH_SEQ)) | |
966 | __blk_account_io_done(req, now); | |
967 | } | |
968 | ||
969 | static void __blk_account_io_start(struct request *rq) | |
970 | { | |
41fa7222 CH |
971 | /* |
972 | * All non-passthrough requests are created from a bio with one | |
973 | * exception: when a flush command that is part of a flush sequence | |
974 | * generated by the state machine in blk-flush.c is cloned onto the | |
975 | * lower device by dm-multipath we can get here without a bio. | |
976 | */ | |
977 | if (rq->bio) | |
450b7879 | 978 | rq->part = rq->bio->bi_bdev; |
41fa7222 | 979 | else |
f3fa33ac | 980 | rq->part = rq->q->disk->part0; |
450b7879 CH |
981 | |
982 | part_stat_lock(); | |
983 | update_io_ticks(rq->part, jiffies, false); | |
984 | part_stat_unlock(); | |
985 | } | |
986 | ||
987 | static inline void blk_account_io_start(struct request *req) | |
988 | { | |
989 | if (blk_do_io_stat(req)) | |
990 | __blk_account_io_start(req); | |
991 | } | |
992 | ||
f794f335 | 993 | static inline void __blk_mq_end_request_acct(struct request *rq, u64 now) |
320ae51f | 994 | { |
4bc6339a OS |
995 | if (rq->rq_flags & RQF_STATS) { |
996 | blk_mq_poll_stats_start(rq->q); | |
522a7775 | 997 | blk_stat_add(rq, now); |
4bc6339a OS |
998 | } |
999 | ||
87890092 | 1000 | blk_mq_sched_completed_request(rq, now); |
522a7775 | 1001 | blk_account_io_done(rq, now); |
f794f335 | 1002 | } |
522a7775 | 1003 | |
f794f335 JA |
1004 | inline void __blk_mq_end_request(struct request *rq, blk_status_t error) |
1005 | { | |
1006 | if (blk_mq_need_time_stamp(rq)) | |
1007 | __blk_mq_end_request_acct(rq, ktime_get_ns()); | |
0d11e6ac | 1008 | |
91b63639 | 1009 | if (rq->end_io) { |
a7905043 | 1010 | rq_qos_done(rq->q, rq); |
de671d61 JA |
1011 | if (rq->end_io(rq, error) == RQ_END_IO_FREE) |
1012 | blk_mq_free_request(rq); | |
91b63639 | 1013 | } else { |
320ae51f | 1014 | blk_mq_free_request(rq); |
91b63639 | 1015 | } |
320ae51f | 1016 | } |
c8a446ad | 1017 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 1018 | |
2a842aca | 1019 | void blk_mq_end_request(struct request *rq, blk_status_t error) |
63151a44 CH |
1020 | { |
1021 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
1022 | BUG(); | |
c8a446ad | 1023 | __blk_mq_end_request(rq, error); |
63151a44 | 1024 | } |
c8a446ad | 1025 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 1026 | |
f794f335 JA |
1027 | #define TAG_COMP_BATCH 32 |
1028 | ||
1029 | static inline void blk_mq_flush_tag_batch(struct blk_mq_hw_ctx *hctx, | |
1030 | int *tag_array, int nr_tags) | |
1031 | { | |
1032 | struct request_queue *q = hctx->queue; | |
1033 | ||
3b87c6ea ML |
1034 | /* |
1035 | * All requests should have been marked as RQF_MQ_INFLIGHT, so | |
1036 | * update hctx->nr_active in batch | |
1037 | */ | |
1038 | if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) | |
1039 | __blk_mq_sub_active_requests(hctx, nr_tags); | |
1040 | ||
f794f335 JA |
1041 | blk_mq_put_tags(hctx->tags, tag_array, nr_tags); |
1042 | percpu_ref_put_many(&q->q_usage_counter, nr_tags); | |
1043 | } | |
1044 | ||
1045 | void blk_mq_end_request_batch(struct io_comp_batch *iob) | |
1046 | { | |
1047 | int tags[TAG_COMP_BATCH], nr_tags = 0; | |
02f7eab0 | 1048 | struct blk_mq_hw_ctx *cur_hctx = NULL; |
f794f335 JA |
1049 | struct request *rq; |
1050 | u64 now = 0; | |
1051 | ||
1052 | if (iob->need_ts) | |
1053 | now = ktime_get_ns(); | |
1054 | ||
1055 | while ((rq = rq_list_pop(&iob->req_list)) != NULL) { | |
1056 | prefetch(rq->bio); | |
1057 | prefetch(rq->rq_next); | |
1058 | ||
5581a5dd | 1059 | blk_complete_request(rq); |
f794f335 JA |
1060 | if (iob->need_ts) |
1061 | __blk_mq_end_request_acct(rq, now); | |
1062 | ||
98b26a0e JA |
1063 | rq_qos_done(rq->q, rq); |
1064 | ||
ab3e1d3b JA |
1065 | /* |
1066 | * If end_io handler returns NONE, then it still has | |
1067 | * ownership of the request. | |
1068 | */ | |
1069 | if (rq->end_io && rq->end_io(rq, 0) == RQ_END_IO_NONE) | |
1070 | continue; | |
1071 | ||
f794f335 | 1072 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); |
0a467d0f | 1073 | if (!req_ref_put_and_test(rq)) |
f794f335 JA |
1074 | continue; |
1075 | ||
1076 | blk_crypto_free_request(rq); | |
1077 | blk_pm_mark_last_busy(rq); | |
f794f335 | 1078 | |
02f7eab0 JA |
1079 | if (nr_tags == TAG_COMP_BATCH || cur_hctx != rq->mq_hctx) { |
1080 | if (cur_hctx) | |
1081 | blk_mq_flush_tag_batch(cur_hctx, tags, nr_tags); | |
f794f335 | 1082 | nr_tags = 0; |
02f7eab0 | 1083 | cur_hctx = rq->mq_hctx; |
f794f335 JA |
1084 | } |
1085 | tags[nr_tags++] = rq->tag; | |
f794f335 JA |
1086 | } |
1087 | ||
1088 | if (nr_tags) | |
02f7eab0 | 1089 | blk_mq_flush_tag_batch(cur_hctx, tags, nr_tags); |
f794f335 JA |
1090 | } |
1091 | EXPORT_SYMBOL_GPL(blk_mq_end_request_batch); | |
1092 | ||
f9ab4918 | 1093 | static void blk_complete_reqs(struct llist_head *list) |
320ae51f | 1094 | { |
f9ab4918 SAS |
1095 | struct llist_node *entry = llist_reverse_order(llist_del_all(list)); |
1096 | struct request *rq, *next; | |
c3077b5d | 1097 | |
f9ab4918 | 1098 | llist_for_each_entry_safe(rq, next, entry, ipi_list) |
c3077b5d | 1099 | rq->q->mq_ops->complete(rq); |
320ae51f | 1100 | } |
320ae51f | 1101 | |
f9ab4918 | 1102 | static __latent_entropy void blk_done_softirq(struct softirq_action *h) |
320ae51f | 1103 | { |
f9ab4918 | 1104 | blk_complete_reqs(this_cpu_ptr(&blk_cpu_done)); |
115243f5 CH |
1105 | } |
1106 | ||
c3077b5d CH |
1107 | static int blk_softirq_cpu_dead(unsigned int cpu) |
1108 | { | |
f9ab4918 | 1109 | blk_complete_reqs(&per_cpu(blk_cpu_done, cpu)); |
c3077b5d CH |
1110 | return 0; |
1111 | } | |
1112 | ||
40d09b53 | 1113 | static void __blk_mq_complete_request_remote(void *data) |
c3077b5d | 1114 | { |
f9ab4918 | 1115 | __raise_softirq_irqoff(BLOCK_SOFTIRQ); |
c3077b5d CH |
1116 | } |
1117 | ||
96339526 CH |
1118 | static inline bool blk_mq_complete_need_ipi(struct request *rq) |
1119 | { | |
1120 | int cpu = raw_smp_processor_id(); | |
1121 | ||
1122 | if (!IS_ENABLED(CONFIG_SMP) || | |
1123 | !test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) | |
1124 | return false; | |
71425189 SAS |
1125 | /* |
1126 | * With force threaded interrupts enabled, raising softirq from an SMP | |
1127 | * function call will always result in waking the ksoftirqd thread. | |
1128 | * This is probably worse than completing the request on a different | |
1129 | * cache domain. | |
1130 | */ | |
91cc470e | 1131 | if (force_irqthreads()) |
71425189 | 1132 | return false; |
96339526 CH |
1133 | |
1134 | /* same CPU or cache domain? Complete locally */ | |
1135 | if (cpu == rq->mq_ctx->cpu || | |
1136 | (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags) && | |
1137 | cpus_share_cache(cpu, rq->mq_ctx->cpu))) | |
1138 | return false; | |
1139 | ||
1140 | /* don't try to IPI to an offline CPU */ | |
1141 | return cpu_online(rq->mq_ctx->cpu); | |
1142 | } | |
1143 | ||
f9ab4918 SAS |
1144 | static void blk_mq_complete_send_ipi(struct request *rq) |
1145 | { | |
1146 | struct llist_head *list; | |
1147 | unsigned int cpu; | |
1148 | ||
1149 | cpu = rq->mq_ctx->cpu; | |
1150 | list = &per_cpu(blk_cpu_done, cpu); | |
1151 | if (llist_add(&rq->ipi_list, list)) { | |
1152 | INIT_CSD(&rq->csd, __blk_mq_complete_request_remote, rq); | |
1153 | smp_call_function_single_async(cpu, &rq->csd); | |
1154 | } | |
1155 | } | |
1156 | ||
1157 | static void blk_mq_raise_softirq(struct request *rq) | |
1158 | { | |
1159 | struct llist_head *list; | |
1160 | ||
1161 | preempt_disable(); | |
1162 | list = this_cpu_ptr(&blk_cpu_done); | |
1163 | if (llist_add(&rq->ipi_list, list)) | |
1164 | raise_softirq(BLOCK_SOFTIRQ); | |
1165 | preempt_enable(); | |
1166 | } | |
1167 | ||
40d09b53 | 1168 | bool blk_mq_complete_request_remote(struct request *rq) |
320ae51f | 1169 | { |
af78ff7c | 1170 | WRITE_ONCE(rq->state, MQ_RQ_COMPLETE); |
36e76539 | 1171 | |
4ab32bf3 | 1172 | /* |
f168420c LS |
1173 | * For request which hctx has only one ctx mapping, |
1174 | * or a polled request, always complete locally, | |
1175 | * it's pointless to redirect the completion. | |
4ab32bf3 | 1176 | */ |
f168420c LS |
1177 | if (rq->mq_hctx->nr_ctx == 1 || |
1178 | rq->cmd_flags & REQ_POLLED) | |
40d09b53 | 1179 | return false; |
38535201 | 1180 | |
96339526 | 1181 | if (blk_mq_complete_need_ipi(rq)) { |
f9ab4918 SAS |
1182 | blk_mq_complete_send_ipi(rq); |
1183 | return true; | |
3d6efbf6 | 1184 | } |
40d09b53 | 1185 | |
f9ab4918 SAS |
1186 | if (rq->q->nr_hw_queues == 1) { |
1187 | blk_mq_raise_softirq(rq); | |
1188 | return true; | |
1189 | } | |
1190 | return false; | |
40d09b53 CH |
1191 | } |
1192 | EXPORT_SYMBOL_GPL(blk_mq_complete_request_remote); | |
1193 | ||
1194 | /** | |
1195 | * blk_mq_complete_request - end I/O on a request | |
1196 | * @rq: the request being processed | |
1197 | * | |
1198 | * Description: | |
1199 | * Complete a request by scheduling the ->complete_rq operation. | |
1200 | **/ | |
1201 | void blk_mq_complete_request(struct request *rq) | |
1202 | { | |
1203 | if (!blk_mq_complete_request_remote(rq)) | |
1204 | rq->q->mq_ops->complete(rq); | |
320ae51f | 1205 | } |
15f73f5b | 1206 | EXPORT_SYMBOL(blk_mq_complete_request); |
30a91cb4 | 1207 | |
105663f7 AA |
1208 | /** |
1209 | * blk_mq_start_request - Start processing a request | |
1210 | * @rq: Pointer to request to be started | |
1211 | * | |
1212 | * Function used by device drivers to notify the block layer that a request | |
1213 | * is going to be processed now, so blk layer can do proper initializations | |
1214 | * such as starting the timeout timer. | |
1215 | */ | |
e2490073 | 1216 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
1217 | { |
1218 | struct request_queue *q = rq->q; | |
1219 | ||
a54895fa | 1220 | trace_block_rq_issue(rq); |
320ae51f | 1221 | |
cf43e6be | 1222 | if (test_bit(QUEUE_FLAG_STATS, &q->queue_flags)) { |
4cddeaca | 1223 | rq->io_start_time_ns = ktime_get_ns(); |
3d244306 | 1224 | rq->stats_sectors = blk_rq_sectors(rq); |
cf43e6be | 1225 | rq->rq_flags |= RQF_STATS; |
a7905043 | 1226 | rq_qos_issue(q, rq); |
cf43e6be JA |
1227 | } |
1228 | ||
1d9bd516 | 1229 | WARN_ON_ONCE(blk_mq_rq_state(rq) != MQ_RQ_IDLE); |
538b7534 | 1230 | |
1d9bd516 | 1231 | blk_add_timer(rq); |
12f5b931 | 1232 | WRITE_ONCE(rq->state, MQ_RQ_IN_FLIGHT); |
49f5baa5 | 1233 | |
54d4e6ab MG |
1234 | #ifdef CONFIG_BLK_DEV_INTEGRITY |
1235 | if (blk_integrity_rq(rq) && req_op(rq) == REQ_OP_WRITE) | |
1236 | q->integrity.profile->prepare_fn(rq); | |
1237 | #endif | |
3e08773c CH |
1238 | if (rq->bio && rq->bio->bi_opf & REQ_POLLED) |
1239 | WRITE_ONCE(rq->bio->bi_cookie, blk_rq_to_qc(rq)); | |
320ae51f | 1240 | } |
e2490073 | 1241 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 1242 | |
a327c341 ML |
1243 | /* |
1244 | * Allow 2x BLK_MAX_REQUEST_COUNT requests on plug queue for multiple | |
1245 | * queues. This is important for md arrays to benefit from merging | |
1246 | * requests. | |
1247 | */ | |
1248 | static inline unsigned short blk_plug_max_rq_count(struct blk_plug *plug) | |
1249 | { | |
1250 | if (plug->multiple_queues) | |
1251 | return BLK_MAX_REQUEST_COUNT * 2; | |
1252 | return BLK_MAX_REQUEST_COUNT; | |
1253 | } | |
1254 | ||
1255 | static void blk_add_rq_to_plug(struct blk_plug *plug, struct request *rq) | |
1256 | { | |
1257 | struct request *last = rq_list_peek(&plug->mq_list); | |
1258 | ||
1259 | if (!plug->rq_count) { | |
1260 | trace_block_plug(rq->q); | |
1261 | } else if (plug->rq_count >= blk_plug_max_rq_count(plug) || | |
1262 | (!blk_queue_nomerges(rq->q) && | |
1263 | blk_rq_bytes(last) >= BLK_PLUG_FLUSH_SIZE)) { | |
1264 | blk_mq_flush_plug_list(plug, false); | |
878eb6e4 | 1265 | last = NULL; |
a327c341 ML |
1266 | trace_block_plug(rq->q); |
1267 | } | |
1268 | ||
1269 | if (!plug->multiple_queues && last && last->q != rq->q) | |
1270 | plug->multiple_queues = true; | |
1271 | if (!plug->has_elevator && (rq->rq_flags & RQF_ELV)) | |
1272 | plug->has_elevator = true; | |
1273 | rq->rq_next = NULL; | |
1274 | rq_list_add(&plug->mq_list, rq); | |
1275 | plug->rq_count++; | |
1276 | } | |
1277 | ||
4054cff9 CH |
1278 | /** |
1279 | * blk_execute_rq_nowait - insert a request to I/O scheduler for execution | |
4054cff9 CH |
1280 | * @rq: request to insert |
1281 | * @at_head: insert request at head or tail of queue | |
4054cff9 CH |
1282 | * |
1283 | * Description: | |
1284 | * Insert a fully prepared request at the back of the I/O scheduler queue | |
1285 | * for execution. Don't wait for completion. | |
1286 | * | |
1287 | * Note: | |
1288 | * This function will invoke @done directly if the queue is dead. | |
1289 | */ | |
e2e53086 | 1290 | void blk_execute_rq_nowait(struct request *rq, bool at_head) |
4054cff9 | 1291 | { |
ae948fd6 CH |
1292 | WARN_ON(irqs_disabled()); |
1293 | WARN_ON(!blk_rq_is_passthrough(rq)); | |
4054cff9 | 1294 | |
ae948fd6 | 1295 | blk_account_io_start(rq); |
110fdb44 PR |
1296 | |
1297 | /* | |
1298 | * As plugging can be enabled for passthrough requests on a zoned | |
1299 | * device, directly accessing the plug instead of using blk_mq_plug() | |
1300 | * should not have any consequences. | |
1301 | */ | |
ae948fd6 CH |
1302 | if (current->plug) |
1303 | blk_add_rq_to_plug(current->plug, rq); | |
1304 | else | |
1305 | blk_mq_sched_insert_request(rq, at_head, true, false); | |
4054cff9 CH |
1306 | } |
1307 | EXPORT_SYMBOL_GPL(blk_execute_rq_nowait); | |
1308 | ||
32ac5a9b CH |
1309 | struct blk_rq_wait { |
1310 | struct completion done; | |
1311 | blk_status_t ret; | |
1312 | }; | |
1313 | ||
de671d61 | 1314 | static enum rq_end_io_ret blk_end_sync_rq(struct request *rq, blk_status_t ret) |
32ac5a9b CH |
1315 | { |
1316 | struct blk_rq_wait *wait = rq->end_io_data; | |
1317 | ||
1318 | wait->ret = ret; | |
1319 | complete(&wait->done); | |
de671d61 | 1320 | return RQ_END_IO_NONE; |
32ac5a9b CH |
1321 | } |
1322 | ||
c6e99ea4 | 1323 | bool blk_rq_is_poll(struct request *rq) |
4054cff9 CH |
1324 | { |
1325 | if (!rq->mq_hctx) | |
1326 | return false; | |
1327 | if (rq->mq_hctx->type != HCTX_TYPE_POLL) | |
1328 | return false; | |
1329 | if (WARN_ON_ONCE(!rq->bio)) | |
1330 | return false; | |
1331 | return true; | |
1332 | } | |
c6e99ea4 | 1333 | EXPORT_SYMBOL_GPL(blk_rq_is_poll); |
4054cff9 CH |
1334 | |
1335 | static void blk_rq_poll_completion(struct request *rq, struct completion *wait) | |
1336 | { | |
1337 | do { | |
1338 | bio_poll(rq->bio, NULL, 0); | |
1339 | cond_resched(); | |
1340 | } while (!completion_done(wait)); | |
1341 | } | |
1342 | ||
1343 | /** | |
1344 | * blk_execute_rq - insert a request into queue for execution | |
4054cff9 CH |
1345 | * @rq: request to insert |
1346 | * @at_head: insert request at head or tail of queue | |
1347 | * | |
1348 | * Description: | |
1349 | * Insert a fully prepared request at the back of the I/O scheduler queue | |
1350 | * for execution and wait for completion. | |
1351 | * Return: The blk_status_t result provided to blk_mq_end_request(). | |
1352 | */ | |
b84ba30b | 1353 | blk_status_t blk_execute_rq(struct request *rq, bool at_head) |
4054cff9 | 1354 | { |
32ac5a9b CH |
1355 | struct blk_rq_wait wait = { |
1356 | .done = COMPLETION_INITIALIZER_ONSTACK(wait.done), | |
1357 | }; | |
4054cff9 | 1358 | |
ae948fd6 CH |
1359 | WARN_ON(irqs_disabled()); |
1360 | WARN_ON(!blk_rq_is_passthrough(rq)); | |
4054cff9 CH |
1361 | |
1362 | rq->end_io_data = &wait; | |
ae948fd6 | 1363 | rq->end_io = blk_end_sync_rq; |
4054cff9 | 1364 | |
ae948fd6 CH |
1365 | blk_account_io_start(rq); |
1366 | blk_mq_sched_insert_request(rq, at_head, true, false); | |
4054cff9 | 1367 | |
ae948fd6 | 1368 | if (blk_rq_is_poll(rq)) { |
32ac5a9b | 1369 | blk_rq_poll_completion(rq, &wait.done); |
ae948fd6 CH |
1370 | } else { |
1371 | /* | |
1372 | * Prevent hang_check timer from firing at us during very long | |
1373 | * I/O | |
1374 | */ | |
1375 | unsigned long hang_check = sysctl_hung_task_timeout_secs; | |
1376 | ||
1377 | if (hang_check) | |
32ac5a9b | 1378 | while (!wait_for_completion_io_timeout(&wait.done, |
ae948fd6 CH |
1379 | hang_check * (HZ/2))) |
1380 | ; | |
1381 | else | |
32ac5a9b | 1382 | wait_for_completion_io(&wait.done); |
ae948fd6 | 1383 | } |
4054cff9 | 1384 | |
32ac5a9b | 1385 | return wait.ret; |
4054cff9 CH |
1386 | } |
1387 | EXPORT_SYMBOL(blk_execute_rq); | |
1388 | ||
ed0791b2 | 1389 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
1390 | { |
1391 | struct request_queue *q = rq->q; | |
1392 | ||
923218f6 ML |
1393 | blk_mq_put_driver_tag(rq); |
1394 | ||
a54895fa | 1395 | trace_block_rq_requeue(rq); |
a7905043 | 1396 | rq_qos_requeue(q, rq); |
49f5baa5 | 1397 | |
12f5b931 KB |
1398 | if (blk_mq_request_started(rq)) { |
1399 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); | |
da661267 | 1400 | rq->rq_flags &= ~RQF_TIMED_OUT; |
e2490073 | 1401 | } |
320ae51f JA |
1402 | } |
1403 | ||
2b053aca | 1404 | void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list) |
ed0791b2 | 1405 | { |
ed0791b2 | 1406 | __blk_mq_requeue_request(rq); |
ed0791b2 | 1407 | |
105976f5 ML |
1408 | /* this request will be re-inserted to io scheduler queue */ |
1409 | blk_mq_sched_requeue_request(rq); | |
1410 | ||
2b053aca | 1411 | blk_mq_add_to_requeue_list(rq, true, kick_requeue_list); |
ed0791b2 CH |
1412 | } |
1413 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
1414 | ||
6fca6a61 CH |
1415 | static void blk_mq_requeue_work(struct work_struct *work) |
1416 | { | |
1417 | struct request_queue *q = | |
2849450a | 1418 | container_of(work, struct request_queue, requeue_work.work); |
6fca6a61 CH |
1419 | LIST_HEAD(rq_list); |
1420 | struct request *rq, *next; | |
6fca6a61 | 1421 | |
18e9781d | 1422 | spin_lock_irq(&q->requeue_lock); |
6fca6a61 | 1423 | list_splice_init(&q->requeue_list, &rq_list); |
18e9781d | 1424 | spin_unlock_irq(&q->requeue_lock); |
6fca6a61 CH |
1425 | |
1426 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
aef1897c | 1427 | if (!(rq->rq_flags & (RQF_SOFTBARRIER | RQF_DONTPREP))) |
6fca6a61 CH |
1428 | continue; |
1429 | ||
e8064021 | 1430 | rq->rq_flags &= ~RQF_SOFTBARRIER; |
6fca6a61 | 1431 | list_del_init(&rq->queuelist); |
aef1897c JW |
1432 | /* |
1433 | * If RQF_DONTPREP, rq has contained some driver specific | |
1434 | * data, so insert it to hctx dispatch list to avoid any | |
1435 | * merge. | |
1436 | */ | |
1437 | if (rq->rq_flags & RQF_DONTPREP) | |
01e99aec | 1438 | blk_mq_request_bypass_insert(rq, false, false); |
aef1897c JW |
1439 | else |
1440 | blk_mq_sched_insert_request(rq, true, false, false); | |
6fca6a61 CH |
1441 | } |
1442 | ||
1443 | while (!list_empty(&rq_list)) { | |
1444 | rq = list_entry(rq_list.next, struct request, queuelist); | |
1445 | list_del_init(&rq->queuelist); | |
9e97d295 | 1446 | blk_mq_sched_insert_request(rq, false, false, false); |
6fca6a61 CH |
1447 | } |
1448 | ||
52d7f1b5 | 1449 | blk_mq_run_hw_queues(q, false); |
6fca6a61 CH |
1450 | } |
1451 | ||
2b053aca BVA |
1452 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, |
1453 | bool kick_requeue_list) | |
6fca6a61 CH |
1454 | { |
1455 | struct request_queue *q = rq->q; | |
1456 | unsigned long flags; | |
1457 | ||
1458 | /* | |
1459 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
ff821d27 | 1460 | * request head insertion from the workqueue. |
6fca6a61 | 1461 | */ |
e8064021 | 1462 | BUG_ON(rq->rq_flags & RQF_SOFTBARRIER); |
6fca6a61 CH |
1463 | |
1464 | spin_lock_irqsave(&q->requeue_lock, flags); | |
1465 | if (at_head) { | |
e8064021 | 1466 | rq->rq_flags |= RQF_SOFTBARRIER; |
6fca6a61 CH |
1467 | list_add(&rq->queuelist, &q->requeue_list); |
1468 | } else { | |
1469 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
1470 | } | |
1471 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
2b053aca BVA |
1472 | |
1473 | if (kick_requeue_list) | |
1474 | blk_mq_kick_requeue_list(q); | |
6fca6a61 | 1475 | } |
6fca6a61 CH |
1476 | |
1477 | void blk_mq_kick_requeue_list(struct request_queue *q) | |
1478 | { | |
ae943d20 | 1479 | kblockd_mod_delayed_work_on(WORK_CPU_UNBOUND, &q->requeue_work, 0); |
6fca6a61 CH |
1480 | } |
1481 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
1482 | ||
2849450a MS |
1483 | void blk_mq_delay_kick_requeue_list(struct request_queue *q, |
1484 | unsigned long msecs) | |
1485 | { | |
d4acf365 BVA |
1486 | kblockd_mod_delayed_work_on(WORK_CPU_UNBOUND, &q->requeue_work, |
1487 | msecs_to_jiffies(msecs)); | |
2849450a MS |
1488 | } |
1489 | EXPORT_SYMBOL(blk_mq_delay_kick_requeue_list); | |
1490 | ||
2dd6532e | 1491 | static bool blk_mq_rq_inflight(struct request *rq, void *priv) |
ae879912 JA |
1492 | { |
1493 | /* | |
8ab30a33 JG |
1494 | * If we find a request that isn't idle we know the queue is busy |
1495 | * as it's checked in the iter. | |
1496 | * Return false to stop the iteration. | |
ae879912 | 1497 | */ |
8ab30a33 | 1498 | if (blk_mq_request_started(rq)) { |
ae879912 JA |
1499 | bool *busy = priv; |
1500 | ||
1501 | *busy = true; | |
1502 | return false; | |
1503 | } | |
1504 | ||
1505 | return true; | |
1506 | } | |
1507 | ||
3c94d83c | 1508 | bool blk_mq_queue_inflight(struct request_queue *q) |
ae879912 JA |
1509 | { |
1510 | bool busy = false; | |
1511 | ||
3c94d83c | 1512 | blk_mq_queue_tag_busy_iter(q, blk_mq_rq_inflight, &busy); |
ae879912 JA |
1513 | return busy; |
1514 | } | |
3c94d83c | 1515 | EXPORT_SYMBOL_GPL(blk_mq_queue_inflight); |
ae879912 | 1516 | |
9bdb4833 | 1517 | static void blk_mq_rq_timed_out(struct request *req) |
320ae51f | 1518 | { |
da661267 | 1519 | req->rq_flags |= RQF_TIMED_OUT; |
d1210d5a CH |
1520 | if (req->q->mq_ops->timeout) { |
1521 | enum blk_eh_timer_return ret; | |
1522 | ||
9bdb4833 | 1523 | ret = req->q->mq_ops->timeout(req); |
d1210d5a CH |
1524 | if (ret == BLK_EH_DONE) |
1525 | return; | |
1526 | WARN_ON_ONCE(ret != BLK_EH_RESET_TIMER); | |
46f92d42 | 1527 | } |
d1210d5a CH |
1528 | |
1529 | blk_add_timer(req); | |
87ee7b11 | 1530 | } |
5b3f25fc | 1531 | |
12f5b931 | 1532 | static bool blk_mq_req_expired(struct request *rq, unsigned long *next) |
81481eb4 | 1533 | { |
12f5b931 | 1534 | unsigned long deadline; |
87ee7b11 | 1535 | |
12f5b931 KB |
1536 | if (blk_mq_rq_state(rq) != MQ_RQ_IN_FLIGHT) |
1537 | return false; | |
da661267 CH |
1538 | if (rq->rq_flags & RQF_TIMED_OUT) |
1539 | return false; | |
a7af0af3 | 1540 | |
079076b3 | 1541 | deadline = READ_ONCE(rq->deadline); |
12f5b931 KB |
1542 | if (time_after_eq(jiffies, deadline)) |
1543 | return true; | |
a7af0af3 | 1544 | |
12f5b931 KB |
1545 | if (*next == 0) |
1546 | *next = deadline; | |
1547 | else if (time_after(*next, deadline)) | |
1548 | *next = deadline; | |
1549 | return false; | |
87ee7b11 JA |
1550 | } |
1551 | ||
2e315dc0 ML |
1552 | void blk_mq_put_rq_ref(struct request *rq) |
1553 | { | |
de671d61 JA |
1554 | if (is_flush_rq(rq)) { |
1555 | if (rq->end_io(rq, 0) == RQ_END_IO_FREE) | |
1556 | blk_mq_free_request(rq); | |
1557 | } else if (req_ref_put_and_test(rq)) { | |
2e315dc0 | 1558 | __blk_mq_free_request(rq); |
de671d61 | 1559 | } |
2e315dc0 ML |
1560 | } |
1561 | ||
2dd6532e | 1562 | static bool blk_mq_check_expired(struct request *rq, void *priv) |
1d9bd516 | 1563 | { |
12f5b931 KB |
1564 | unsigned long *next = priv; |
1565 | ||
1566 | /* | |
c797b40c ML |
1567 | * blk_mq_queue_tag_busy_iter() has locked the request, so it cannot |
1568 | * be reallocated underneath the timeout handler's processing, then | |
1569 | * the expire check is reliable. If the request is not expired, then | |
1570 | * it was completed and reallocated as a new request after returning | |
1571 | * from blk_mq_check_expired(). | |
1d9bd516 | 1572 | */ |
12f5b931 | 1573 | if (blk_mq_req_expired(rq, next)) |
9bdb4833 | 1574 | blk_mq_rq_timed_out(rq); |
7baa8572 | 1575 | return true; |
1d9bd516 TH |
1576 | } |
1577 | ||
287922eb | 1578 | static void blk_mq_timeout_work(struct work_struct *work) |
320ae51f | 1579 | { |
287922eb CH |
1580 | struct request_queue *q = |
1581 | container_of(work, struct request_queue, timeout_work); | |
12f5b931 | 1582 | unsigned long next = 0; |
1d9bd516 | 1583 | struct blk_mq_hw_ctx *hctx; |
4f481208 | 1584 | unsigned long i; |
320ae51f | 1585 | |
71f79fb3 GKB |
1586 | /* A deadlock might occur if a request is stuck requiring a |
1587 | * timeout at the same time a queue freeze is waiting | |
1588 | * completion, since the timeout code would not be able to | |
1589 | * acquire the queue reference here. | |
1590 | * | |
1591 | * That's why we don't use blk_queue_enter here; instead, we use | |
1592 | * percpu_ref_tryget directly, because we need to be able to | |
1593 | * obtain a reference even in the short window between the queue | |
1594 | * starting to freeze, by dropping the first reference in | |
1671d522 | 1595 | * blk_freeze_queue_start, and the moment the last request is |
71f79fb3 GKB |
1596 | * consumed, marked by the instant q_usage_counter reaches |
1597 | * zero. | |
1598 | */ | |
1599 | if (!percpu_ref_tryget(&q->q_usage_counter)) | |
287922eb CH |
1600 | return; |
1601 | ||
12f5b931 | 1602 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &next); |
320ae51f | 1603 | |
12f5b931 KB |
1604 | if (next != 0) { |
1605 | mod_timer(&q->timeout, next); | |
0d2602ca | 1606 | } else { |
fcd36c36 BVA |
1607 | /* |
1608 | * Request timeouts are handled as a forward rolling timer. If | |
1609 | * we end up here it means that no requests are pending and | |
1610 | * also that no request has been pending for a while. Mark | |
1611 | * each hctx as idle. | |
1612 | */ | |
f054b56c ML |
1613 | queue_for_each_hw_ctx(q, hctx, i) { |
1614 | /* the hctx may be unmapped, so check it here */ | |
1615 | if (blk_mq_hw_queue_mapped(hctx)) | |
1616 | blk_mq_tag_idle(hctx); | |
1617 | } | |
0d2602ca | 1618 | } |
287922eb | 1619 | blk_queue_exit(q); |
320ae51f JA |
1620 | } |
1621 | ||
88459642 OS |
1622 | struct flush_busy_ctx_data { |
1623 | struct blk_mq_hw_ctx *hctx; | |
1624 | struct list_head *list; | |
1625 | }; | |
1626 | ||
1627 | static bool flush_busy_ctx(struct sbitmap *sb, unsigned int bitnr, void *data) | |
1628 | { | |
1629 | struct flush_busy_ctx_data *flush_data = data; | |
1630 | struct blk_mq_hw_ctx *hctx = flush_data->hctx; | |
1631 | struct blk_mq_ctx *ctx = hctx->ctxs[bitnr]; | |
c16d6b5a | 1632 | enum hctx_type type = hctx->type; |
88459642 | 1633 | |
88459642 | 1634 | spin_lock(&ctx->lock); |
c16d6b5a | 1635 | list_splice_tail_init(&ctx->rq_lists[type], flush_data->list); |
e9a99a63 | 1636 | sbitmap_clear_bit(sb, bitnr); |
88459642 OS |
1637 | spin_unlock(&ctx->lock); |
1638 | return true; | |
1639 | } | |
1640 | ||
1429d7c9 JA |
1641 | /* |
1642 | * Process software queues that have been marked busy, splicing them | |
1643 | * to the for-dispatch | |
1644 | */ | |
2c3ad667 | 1645 | void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) |
1429d7c9 | 1646 | { |
88459642 OS |
1647 | struct flush_busy_ctx_data data = { |
1648 | .hctx = hctx, | |
1649 | .list = list, | |
1650 | }; | |
1429d7c9 | 1651 | |
88459642 | 1652 | sbitmap_for_each_set(&hctx->ctx_map, flush_busy_ctx, &data); |
1429d7c9 | 1653 | } |
2c3ad667 | 1654 | EXPORT_SYMBOL_GPL(blk_mq_flush_busy_ctxs); |
1429d7c9 | 1655 | |
b347689f ML |
1656 | struct dispatch_rq_data { |
1657 | struct blk_mq_hw_ctx *hctx; | |
1658 | struct request *rq; | |
1659 | }; | |
1660 | ||
1661 | static bool dispatch_rq_from_ctx(struct sbitmap *sb, unsigned int bitnr, | |
1662 | void *data) | |
1663 | { | |
1664 | struct dispatch_rq_data *dispatch_data = data; | |
1665 | struct blk_mq_hw_ctx *hctx = dispatch_data->hctx; | |
1666 | struct blk_mq_ctx *ctx = hctx->ctxs[bitnr]; | |
c16d6b5a | 1667 | enum hctx_type type = hctx->type; |
b347689f ML |
1668 | |
1669 | spin_lock(&ctx->lock); | |
c16d6b5a ML |
1670 | if (!list_empty(&ctx->rq_lists[type])) { |
1671 | dispatch_data->rq = list_entry_rq(ctx->rq_lists[type].next); | |
b347689f | 1672 | list_del_init(&dispatch_data->rq->queuelist); |
c16d6b5a | 1673 | if (list_empty(&ctx->rq_lists[type])) |
b347689f ML |
1674 | sbitmap_clear_bit(sb, bitnr); |
1675 | } | |
1676 | spin_unlock(&ctx->lock); | |
1677 | ||
1678 | return !dispatch_data->rq; | |
1679 | } | |
1680 | ||
1681 | struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx, | |
1682 | struct blk_mq_ctx *start) | |
1683 | { | |
f31967f0 | 1684 | unsigned off = start ? start->index_hw[hctx->type] : 0; |
b347689f ML |
1685 | struct dispatch_rq_data data = { |
1686 | .hctx = hctx, | |
1687 | .rq = NULL, | |
1688 | }; | |
1689 | ||
1690 | __sbitmap_for_each_set(&hctx->ctx_map, off, | |
1691 | dispatch_rq_from_ctx, &data); | |
1692 | ||
1693 | return data.rq; | |
1694 | } | |
1695 | ||
a808a9d5 | 1696 | static bool __blk_mq_alloc_driver_tag(struct request *rq) |
570e9b73 | 1697 | { |
ae0f1a73 | 1698 | struct sbitmap_queue *bt = &rq->mq_hctx->tags->bitmap_tags; |
570e9b73 | 1699 | unsigned int tag_offset = rq->mq_hctx->tags->nr_reserved_tags; |
570e9b73 ML |
1700 | int tag; |
1701 | ||
568f2700 ML |
1702 | blk_mq_tag_busy(rq->mq_hctx); |
1703 | ||
570e9b73 | 1704 | if (blk_mq_tag_is_reserved(rq->mq_hctx->sched_tags, rq->internal_tag)) { |
ae0f1a73 | 1705 | bt = &rq->mq_hctx->tags->breserved_tags; |
570e9b73 | 1706 | tag_offset = 0; |
28500850 ML |
1707 | } else { |
1708 | if (!hctx_may_queue(rq->mq_hctx, bt)) | |
1709 | return false; | |
570e9b73 ML |
1710 | } |
1711 | ||
570e9b73 ML |
1712 | tag = __sbitmap_queue_get(bt); |
1713 | if (tag == BLK_MQ_NO_TAG) | |
1714 | return false; | |
1715 | ||
1716 | rq->tag = tag + tag_offset; | |
570e9b73 ML |
1717 | return true; |
1718 | } | |
1719 | ||
a808a9d5 | 1720 | bool __blk_mq_get_driver_tag(struct blk_mq_hw_ctx *hctx, struct request *rq) |
570e9b73 | 1721 | { |
a808a9d5 | 1722 | if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_alloc_driver_tag(rq)) |
568f2700 ML |
1723 | return false; |
1724 | ||
51db1c37 | 1725 | if ((hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) && |
568f2700 ML |
1726 | !(rq->rq_flags & RQF_MQ_INFLIGHT)) { |
1727 | rq->rq_flags |= RQF_MQ_INFLIGHT; | |
bccf5e26 | 1728 | __blk_mq_inc_active_requests(hctx); |
568f2700 ML |
1729 | } |
1730 | hctx->tags->rqs[rq->tag] = rq; | |
1731 | return true; | |
570e9b73 ML |
1732 | } |
1733 | ||
eb619fdb JA |
1734 | static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, |
1735 | int flags, void *key) | |
da55f2cc OS |
1736 | { |
1737 | struct blk_mq_hw_ctx *hctx; | |
1738 | ||
1739 | hctx = container_of(wait, struct blk_mq_hw_ctx, dispatch_wait); | |
1740 | ||
5815839b | 1741 | spin_lock(&hctx->dispatch_wait_lock); |
e8618575 JA |
1742 | if (!list_empty(&wait->entry)) { |
1743 | struct sbitmap_queue *sbq; | |
1744 | ||
1745 | list_del_init(&wait->entry); | |
ae0f1a73 | 1746 | sbq = &hctx->tags->bitmap_tags; |
e8618575 JA |
1747 | atomic_dec(&sbq->ws_active); |
1748 | } | |
5815839b ML |
1749 | spin_unlock(&hctx->dispatch_wait_lock); |
1750 | ||
da55f2cc OS |
1751 | blk_mq_run_hw_queue(hctx, true); |
1752 | return 1; | |
1753 | } | |
1754 | ||
f906a6a0 JA |
1755 | /* |
1756 | * Mark us waiting for a tag. For shared tags, this involves hooking us into | |
ee3e4de5 BVA |
1757 | * the tag wakeups. For non-shared tags, we can simply mark us needing a |
1758 | * restart. For both cases, take care to check the condition again after | |
f906a6a0 JA |
1759 | * marking us as waiting. |
1760 | */ | |
2278d69f | 1761 | static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx, |
f906a6a0 | 1762 | struct request *rq) |
da55f2cc | 1763 | { |
ae0f1a73 | 1764 | struct sbitmap_queue *sbq = &hctx->tags->bitmap_tags; |
5815839b | 1765 | struct wait_queue_head *wq; |
f906a6a0 JA |
1766 | wait_queue_entry_t *wait; |
1767 | bool ret; | |
da55f2cc | 1768 | |
51db1c37 | 1769 | if (!(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) { |
684b7324 | 1770 | blk_mq_sched_mark_restart_hctx(hctx); |
f906a6a0 | 1771 | |
c27d53fb BVA |
1772 | /* |
1773 | * It's possible that a tag was freed in the window between the | |
1774 | * allocation failure and adding the hardware queue to the wait | |
1775 | * queue. | |
1776 | * | |
1777 | * Don't clear RESTART here, someone else could have set it. | |
1778 | * At most this will cost an extra queue run. | |
1779 | */ | |
8ab6bb9e | 1780 | return blk_mq_get_driver_tag(rq); |
eb619fdb | 1781 | } |
eb619fdb | 1782 | |
2278d69f | 1783 | wait = &hctx->dispatch_wait; |
c27d53fb BVA |
1784 | if (!list_empty_careful(&wait->entry)) |
1785 | return false; | |
1786 | ||
e8618575 | 1787 | wq = &bt_wait_ptr(sbq, hctx)->wait; |
5815839b ML |
1788 | |
1789 | spin_lock_irq(&wq->lock); | |
1790 | spin_lock(&hctx->dispatch_wait_lock); | |
c27d53fb | 1791 | if (!list_empty(&wait->entry)) { |
5815839b ML |
1792 | spin_unlock(&hctx->dispatch_wait_lock); |
1793 | spin_unlock_irq(&wq->lock); | |
c27d53fb | 1794 | return false; |
eb619fdb JA |
1795 | } |
1796 | ||
e8618575 | 1797 | atomic_inc(&sbq->ws_active); |
5815839b ML |
1798 | wait->flags &= ~WQ_FLAG_EXCLUSIVE; |
1799 | __add_wait_queue(wq, wait); | |
c27d53fb | 1800 | |
da55f2cc | 1801 | /* |
eb619fdb JA |
1802 | * It's possible that a tag was freed in the window between the |
1803 | * allocation failure and adding the hardware queue to the wait | |
1804 | * queue. | |
da55f2cc | 1805 | */ |
8ab6bb9e | 1806 | ret = blk_mq_get_driver_tag(rq); |
c27d53fb | 1807 | if (!ret) { |
5815839b ML |
1808 | spin_unlock(&hctx->dispatch_wait_lock); |
1809 | spin_unlock_irq(&wq->lock); | |
c27d53fb | 1810 | return false; |
eb619fdb | 1811 | } |
c27d53fb BVA |
1812 | |
1813 | /* | |
1814 | * We got a tag, remove ourselves from the wait queue to ensure | |
1815 | * someone else gets the wakeup. | |
1816 | */ | |
c27d53fb | 1817 | list_del_init(&wait->entry); |
e8618575 | 1818 | atomic_dec(&sbq->ws_active); |
5815839b ML |
1819 | spin_unlock(&hctx->dispatch_wait_lock); |
1820 | spin_unlock_irq(&wq->lock); | |
c27d53fb BVA |
1821 | |
1822 | return true; | |
da55f2cc OS |
1823 | } |
1824 | ||
6e768717 ML |
1825 | #define BLK_MQ_DISPATCH_BUSY_EWMA_WEIGHT 8 |
1826 | #define BLK_MQ_DISPATCH_BUSY_EWMA_FACTOR 4 | |
1827 | /* | |
1828 | * Update dispatch busy with the Exponential Weighted Moving Average(EWMA): | |
1829 | * - EWMA is one simple way to compute running average value | |
1830 | * - weight(7/8 and 1/8) is applied so that it can decrease exponentially | |
1831 | * - take 4 as factor for avoiding to get too small(0) result, and this | |
1832 | * factor doesn't matter because EWMA decreases exponentially | |
1833 | */ | |
1834 | static void blk_mq_update_dispatch_busy(struct blk_mq_hw_ctx *hctx, bool busy) | |
1835 | { | |
1836 | unsigned int ewma; | |
1837 | ||
6e768717 ML |
1838 | ewma = hctx->dispatch_busy; |
1839 | ||
1840 | if (!ewma && !busy) | |
1841 | return; | |
1842 | ||
1843 | ewma *= BLK_MQ_DISPATCH_BUSY_EWMA_WEIGHT - 1; | |
1844 | if (busy) | |
1845 | ewma += 1 << BLK_MQ_DISPATCH_BUSY_EWMA_FACTOR; | |
1846 | ewma /= BLK_MQ_DISPATCH_BUSY_EWMA_WEIGHT; | |
1847 | ||
1848 | hctx->dispatch_busy = ewma; | |
1849 | } | |
1850 | ||
86ff7c2a ML |
1851 | #define BLK_MQ_RESOURCE_DELAY 3 /* ms units */ |
1852 | ||
c92a4103 JT |
1853 | static void blk_mq_handle_dev_resource(struct request *rq, |
1854 | struct list_head *list) | |
1855 | { | |
1856 | struct request *next = | |
1857 | list_first_entry_or_null(list, struct request, queuelist); | |
1858 | ||
1859 | /* | |
1860 | * If an I/O scheduler has been configured and we got a driver tag for | |
1861 | * the next request already, free it. | |
1862 | */ | |
1863 | if (next) | |
1864 | blk_mq_put_driver_tag(next); | |
1865 | ||
1866 | list_add(&rq->queuelist, list); | |
1867 | __blk_mq_requeue_request(rq); | |
1868 | } | |
1869 | ||
0512a75b KB |
1870 | static void blk_mq_handle_zone_resource(struct request *rq, |
1871 | struct list_head *zone_list) | |
1872 | { | |
1873 | /* | |
1874 | * If we end up here it is because we cannot dispatch a request to a | |
1875 | * specific zone due to LLD level zone-write locking or other zone | |
1876 | * related resource not being available. In this case, set the request | |
1877 | * aside in zone_list for retrying it later. | |
1878 | */ | |
1879 | list_add(&rq->queuelist, zone_list); | |
1880 | __blk_mq_requeue_request(rq); | |
1881 | } | |
1882 | ||
75383524 ML |
1883 | enum prep_dispatch { |
1884 | PREP_DISPATCH_OK, | |
1885 | PREP_DISPATCH_NO_TAG, | |
1886 | PREP_DISPATCH_NO_BUDGET, | |
1887 | }; | |
1888 | ||
1889 | static enum prep_dispatch blk_mq_prep_dispatch_rq(struct request *rq, | |
1890 | bool need_budget) | |
1891 | { | |
1892 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; | |
2a5a24aa | 1893 | int budget_token = -1; |
75383524 | 1894 | |
2a5a24aa ML |
1895 | if (need_budget) { |
1896 | budget_token = blk_mq_get_dispatch_budget(rq->q); | |
1897 | if (budget_token < 0) { | |
1898 | blk_mq_put_driver_tag(rq); | |
1899 | return PREP_DISPATCH_NO_BUDGET; | |
1900 | } | |
1901 | blk_mq_set_rq_budget_token(rq, budget_token); | |
75383524 ML |
1902 | } |
1903 | ||
1904 | if (!blk_mq_get_driver_tag(rq)) { | |
1905 | /* | |
1906 | * The initial allocation attempt failed, so we need to | |
1907 | * rerun the hardware queue when a tag is freed. The | |
1908 | * waitqueue takes care of that. If the queue is run | |
1909 | * before we add this entry back on the dispatch list, | |
1910 | * we'll re-run it below. | |
1911 | */ | |
1912 | if (!blk_mq_mark_tag_wait(hctx, rq)) { | |
1fd40b5e ML |
1913 | /* |
1914 | * All budgets not got from this function will be put | |
1915 | * together during handling partial dispatch | |
1916 | */ | |
1917 | if (need_budget) | |
2a5a24aa | 1918 | blk_mq_put_dispatch_budget(rq->q, budget_token); |
75383524 ML |
1919 | return PREP_DISPATCH_NO_TAG; |
1920 | } | |
1921 | } | |
1922 | ||
1923 | return PREP_DISPATCH_OK; | |
1924 | } | |
1925 | ||
1fd40b5e ML |
1926 | /* release all allocated budgets before calling to blk_mq_dispatch_rq_list */ |
1927 | static void blk_mq_release_budgets(struct request_queue *q, | |
2a5a24aa | 1928 | struct list_head *list) |
1fd40b5e | 1929 | { |
2a5a24aa | 1930 | struct request *rq; |
1fd40b5e | 1931 | |
2a5a24aa ML |
1932 | list_for_each_entry(rq, list, queuelist) { |
1933 | int budget_token = blk_mq_get_rq_budget_token(rq); | |
1fd40b5e | 1934 | |
2a5a24aa ML |
1935 | if (budget_token >= 0) |
1936 | blk_mq_put_dispatch_budget(q, budget_token); | |
1937 | } | |
1fd40b5e ML |
1938 | } |
1939 | ||
1f57f8d4 JA |
1940 | /* |
1941 | * Returns true if we did some work AND can potentially do more. | |
1942 | */ | |
445874e8 | 1943 | bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, |
1fd40b5e | 1944 | unsigned int nr_budgets) |
320ae51f | 1945 | { |
75383524 | 1946 | enum prep_dispatch prep; |
445874e8 | 1947 | struct request_queue *q = hctx->queue; |
6d6f167c | 1948 | struct request *rq, *nxt; |
fc17b653 | 1949 | int errors, queued; |
86ff7c2a | 1950 | blk_status_t ret = BLK_STS_OK; |
0512a75b | 1951 | LIST_HEAD(zone_list); |
9586e67b | 1952 | bool needs_resource = false; |
320ae51f | 1953 | |
81380ca1 OS |
1954 | if (list_empty(list)) |
1955 | return false; | |
1956 | ||
320ae51f JA |
1957 | /* |
1958 | * Now process all the entries, sending them to the driver. | |
1959 | */ | |
93efe981 | 1960 | errors = queued = 0; |
81380ca1 | 1961 | do { |
74c45052 | 1962 | struct blk_mq_queue_data bd; |
320ae51f | 1963 | |
f04c3df3 | 1964 | rq = list_first_entry(list, struct request, queuelist); |
0bca799b | 1965 | |
445874e8 | 1966 | WARN_ON_ONCE(hctx != rq->mq_hctx); |
1fd40b5e | 1967 | prep = blk_mq_prep_dispatch_rq(rq, !nr_budgets); |
75383524 | 1968 | if (prep != PREP_DISPATCH_OK) |
0bca799b | 1969 | break; |
de148297 | 1970 | |
320ae51f | 1971 | list_del_init(&rq->queuelist); |
320ae51f | 1972 | |
74c45052 | 1973 | bd.rq = rq; |
113285b4 JA |
1974 | |
1975 | /* | |
1976 | * Flag last if we have no more requests, or if we have more | |
1977 | * but can't assign a driver tag to it. | |
1978 | */ | |
1979 | if (list_empty(list)) | |
1980 | bd.last = true; | |
1981 | else { | |
113285b4 | 1982 | nxt = list_first_entry(list, struct request, queuelist); |
8ab6bb9e | 1983 | bd.last = !blk_mq_get_driver_tag(nxt); |
113285b4 | 1984 | } |
74c45052 | 1985 | |
1fd40b5e ML |
1986 | /* |
1987 | * once the request is queued to lld, no need to cover the | |
1988 | * budget any more | |
1989 | */ | |
1990 | if (nr_budgets) | |
1991 | nr_budgets--; | |
74c45052 | 1992 | ret = q->mq_ops->queue_rq(hctx, &bd); |
7bf13729 ML |
1993 | switch (ret) { |
1994 | case BLK_STS_OK: | |
1995 | queued++; | |
320ae51f | 1996 | break; |
7bf13729 | 1997 | case BLK_STS_RESOURCE: |
9586e67b NA |
1998 | needs_resource = true; |
1999 | fallthrough; | |
7bf13729 ML |
2000 | case BLK_STS_DEV_RESOURCE: |
2001 | blk_mq_handle_dev_resource(rq, list); | |
2002 | goto out; | |
2003 | case BLK_STS_ZONE_RESOURCE: | |
0512a75b KB |
2004 | /* |
2005 | * Move the request to zone_list and keep going through | |
2006 | * the dispatch list to find more requests the drive can | |
2007 | * accept. | |
2008 | */ | |
2009 | blk_mq_handle_zone_resource(rq, &zone_list); | |
9586e67b | 2010 | needs_resource = true; |
7bf13729 ML |
2011 | break; |
2012 | default: | |
93efe981 | 2013 | errors++; |
e21ee5a6 | 2014 | blk_mq_end_request(rq, ret); |
320ae51f | 2015 | } |
81380ca1 | 2016 | } while (!list_empty(list)); |
7bf13729 | 2017 | out: |
0512a75b KB |
2018 | if (!list_empty(&zone_list)) |
2019 | list_splice_tail_init(&zone_list, list); | |
2020 | ||
632bfb63 | 2021 | /* If we didn't flush the entire list, we could have told the driver |
2022 | * there was more coming, but that turned out to be a lie. | |
2023 | */ | |
65fac0d5 YK |
2024 | if ((!list_empty(list) || errors || needs_resource || |
2025 | ret == BLK_STS_DEV_RESOURCE) && q->mq_ops->commit_rqs && queued) | |
632bfb63 | 2026 | q->mq_ops->commit_rqs(hctx); |
320ae51f JA |
2027 | /* |
2028 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
2029 | * that is where we will continue on next queue run. | |
2030 | */ | |
f04c3df3 | 2031 | if (!list_empty(list)) { |
86ff7c2a | 2032 | bool needs_restart; |
75383524 ML |
2033 | /* For non-shared tags, the RESTART check will suffice */ |
2034 | bool no_tag = prep == PREP_DISPATCH_NO_TAG && | |
51db1c37 | 2035 | (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED); |
86ff7c2a | 2036 | |
2a5a24aa ML |
2037 | if (nr_budgets) |
2038 | blk_mq_release_budgets(q, list); | |
86ff7c2a | 2039 | |
320ae51f | 2040 | spin_lock(&hctx->lock); |
01e99aec | 2041 | list_splice_tail_init(list, &hctx->dispatch); |
320ae51f | 2042 | spin_unlock(&hctx->lock); |
f04c3df3 | 2043 | |
d7d8535f ML |
2044 | /* |
2045 | * Order adding requests to hctx->dispatch and checking | |
2046 | * SCHED_RESTART flag. The pair of this smp_mb() is the one | |
2047 | * in blk_mq_sched_restart(). Avoid restart code path to | |
2048 | * miss the new added requests to hctx->dispatch, meantime | |
2049 | * SCHED_RESTART is observed here. | |
2050 | */ | |
2051 | smp_mb(); | |
2052 | ||
9ba52e58 | 2053 | /* |
710c785f BVA |
2054 | * If SCHED_RESTART was set by the caller of this function and |
2055 | * it is no longer set that means that it was cleared by another | |
2056 | * thread and hence that a queue rerun is needed. | |
9ba52e58 | 2057 | * |
eb619fdb JA |
2058 | * If 'no_tag' is set, that means that we failed getting |
2059 | * a driver tag with an I/O scheduler attached. If our dispatch | |
2060 | * waitqueue is no longer active, ensure that we run the queue | |
2061 | * AFTER adding our entries back to the list. | |
bd166ef1 | 2062 | * |
710c785f BVA |
2063 | * If no I/O scheduler has been configured it is possible that |
2064 | * the hardware queue got stopped and restarted before requests | |
2065 | * were pushed back onto the dispatch list. Rerun the queue to | |
2066 | * avoid starvation. Notes: | |
2067 | * - blk_mq_run_hw_queue() checks whether or not a queue has | |
2068 | * been stopped before rerunning a queue. | |
2069 | * - Some but not all block drivers stop a queue before | |
fc17b653 | 2070 | * returning BLK_STS_RESOURCE. Two exceptions are scsi-mq |
710c785f | 2071 | * and dm-rq. |
86ff7c2a ML |
2072 | * |
2073 | * If driver returns BLK_STS_RESOURCE and SCHED_RESTART | |
2074 | * bit is set, run queue after a delay to avoid IO stalls | |
ab3cee37 | 2075 | * that could otherwise occur if the queue is idle. We'll do |
9586e67b NA |
2076 | * similar if we couldn't get budget or couldn't lock a zone |
2077 | * and SCHED_RESTART is set. | |
bd166ef1 | 2078 | */ |
86ff7c2a | 2079 | needs_restart = blk_mq_sched_needs_restart(hctx); |
9586e67b NA |
2080 | if (prep == PREP_DISPATCH_NO_BUDGET) |
2081 | needs_resource = true; | |
86ff7c2a | 2082 | if (!needs_restart || |
eb619fdb | 2083 | (no_tag && list_empty_careful(&hctx->dispatch_wait.entry))) |
bd166ef1 | 2084 | blk_mq_run_hw_queue(hctx, true); |
6d5e8d21 | 2085 | else if (needs_resource) |
86ff7c2a | 2086 | blk_mq_delay_run_hw_queue(hctx, BLK_MQ_RESOURCE_DELAY); |
1f57f8d4 | 2087 | |
6e768717 | 2088 | blk_mq_update_dispatch_busy(hctx, true); |
1f57f8d4 | 2089 | return false; |
6e768717 ML |
2090 | } else |
2091 | blk_mq_update_dispatch_busy(hctx, false); | |
f04c3df3 | 2092 | |
93efe981 | 2093 | return (queued + errors) != 0; |
f04c3df3 JA |
2094 | } |
2095 | ||
105663f7 AA |
2096 | /** |
2097 | * __blk_mq_run_hw_queue - Run a hardware queue. | |
2098 | * @hctx: Pointer to the hardware queue to run. | |
2099 | * | |
2100 | * Send pending requests to the hardware. | |
2101 | */ | |
6a83e74d BVA |
2102 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) |
2103 | { | |
b7a71e66 JA |
2104 | /* |
2105 | * We can't run the queue inline with ints disabled. Ensure that | |
2106 | * we catch bad users of this early. | |
2107 | */ | |
2108 | WARN_ON_ONCE(in_interrupt()); | |
2109 | ||
bcc330f4 ML |
2110 | blk_mq_run_dispatch_ops(hctx->queue, |
2111 | blk_mq_sched_dispatch_requests(hctx)); | |
6a83e74d BVA |
2112 | } |
2113 | ||
f82ddf19 ML |
2114 | static inline int blk_mq_first_mapped_cpu(struct blk_mq_hw_ctx *hctx) |
2115 | { | |
2116 | int cpu = cpumask_first_and(hctx->cpumask, cpu_online_mask); | |
2117 | ||
2118 | if (cpu >= nr_cpu_ids) | |
2119 | cpu = cpumask_first(hctx->cpumask); | |
2120 | return cpu; | |
2121 | } | |
2122 | ||
506e931f JA |
2123 | /* |
2124 | * It'd be great if the workqueue API had a way to pass | |
2125 | * in a mask and had some smarts for more clever placement. | |
2126 | * For now we just round-robin here, switching for every | |
2127 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
2128 | */ | |
2129 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
2130 | { | |
7bed4595 | 2131 | bool tried = false; |
476f8c98 | 2132 | int next_cpu = hctx->next_cpu; |
7bed4595 | 2133 | |
b657d7e6 CH |
2134 | if (hctx->queue->nr_hw_queues == 1) |
2135 | return WORK_CPU_UNBOUND; | |
506e931f JA |
2136 | |
2137 | if (--hctx->next_cpu_batch <= 0) { | |
7bed4595 | 2138 | select_cpu: |
476f8c98 | 2139 | next_cpu = cpumask_next_and(next_cpu, hctx->cpumask, |
20e4d813 | 2140 | cpu_online_mask); |
506e931f | 2141 | if (next_cpu >= nr_cpu_ids) |
f82ddf19 | 2142 | next_cpu = blk_mq_first_mapped_cpu(hctx); |
506e931f JA |
2143 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; |
2144 | } | |
2145 | ||
7bed4595 ML |
2146 | /* |
2147 | * Do unbound schedule if we can't find a online CPU for this hctx, | |
2148 | * and it should only happen in the path of handling CPU DEAD. | |
2149 | */ | |
476f8c98 | 2150 | if (!cpu_online(next_cpu)) { |
7bed4595 ML |
2151 | if (!tried) { |
2152 | tried = true; | |
2153 | goto select_cpu; | |
2154 | } | |
2155 | ||
2156 | /* | |
2157 | * Make sure to re-select CPU next time once after CPUs | |
2158 | * in hctx->cpumask become online again. | |
2159 | */ | |
476f8c98 | 2160 | hctx->next_cpu = next_cpu; |
7bed4595 ML |
2161 | hctx->next_cpu_batch = 1; |
2162 | return WORK_CPU_UNBOUND; | |
2163 | } | |
476f8c98 ML |
2164 | |
2165 | hctx->next_cpu = next_cpu; | |
2166 | return next_cpu; | |
506e931f JA |
2167 | } |
2168 | ||
105663f7 AA |
2169 | /** |
2170 | * __blk_mq_delay_run_hw_queue - Run (or schedule to run) a hardware queue. | |
2171 | * @hctx: Pointer to the hardware queue to run. | |
2172 | * @async: If we want to run the queue asynchronously. | |
fa94ba8a | 2173 | * @msecs: Milliseconds of delay to wait before running the queue. |
105663f7 AA |
2174 | * |
2175 | * If !@async, try to run the queue now. Else, run the queue asynchronously and | |
2176 | * with a delay of @msecs. | |
2177 | */ | |
7587a5ae BVA |
2178 | static void __blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async, |
2179 | unsigned long msecs) | |
320ae51f | 2180 | { |
5435c023 | 2181 | if (unlikely(blk_mq_hctx_stopped(hctx))) |
320ae51f JA |
2182 | return; |
2183 | ||
1b792f2f | 2184 | if (!async && !(hctx->flags & BLK_MQ_F_BLOCKING)) { |
3c8f9da4 | 2185 | if (cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)) { |
398205b8 | 2186 | __blk_mq_run_hw_queue(hctx); |
398205b8 PB |
2187 | return; |
2188 | } | |
e4043dcf | 2189 | } |
398205b8 | 2190 | |
ae943d20 BVA |
2191 | kblockd_mod_delayed_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work, |
2192 | msecs_to_jiffies(msecs)); | |
7587a5ae BVA |
2193 | } |
2194 | ||
105663f7 AA |
2195 | /** |
2196 | * blk_mq_delay_run_hw_queue - Run a hardware queue asynchronously. | |
2197 | * @hctx: Pointer to the hardware queue to run. | |
fa94ba8a | 2198 | * @msecs: Milliseconds of delay to wait before running the queue. |
105663f7 AA |
2199 | * |
2200 | * Run a hardware queue asynchronously with a delay of @msecs. | |
2201 | */ | |
7587a5ae BVA |
2202 | void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) |
2203 | { | |
2204 | __blk_mq_delay_run_hw_queue(hctx, true, msecs); | |
2205 | } | |
2206 | EXPORT_SYMBOL(blk_mq_delay_run_hw_queue); | |
2207 | ||
105663f7 AA |
2208 | /** |
2209 | * blk_mq_run_hw_queue - Start to run a hardware queue. | |
2210 | * @hctx: Pointer to the hardware queue to run. | |
2211 | * @async: If we want to run the queue asynchronously. | |
2212 | * | |
2213 | * Check if the request queue is not in a quiesced state and if there are | |
2214 | * pending requests to be sent. If this is true, run the queue to send requests | |
2215 | * to hardware. | |
2216 | */ | |
626fb735 | 2217 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
7587a5ae | 2218 | { |
24f5a90f ML |
2219 | bool need_run; |
2220 | ||
2221 | /* | |
2222 | * When queue is quiesced, we may be switching io scheduler, or | |
2223 | * updating nr_hw_queues, or other things, and we can't run queue | |
2224 | * any more, even __blk_mq_hctx_has_pending() can't be called safely. | |
2225 | * | |
2226 | * And queue will be rerun in blk_mq_unquiesce_queue() if it is | |
2227 | * quiesced. | |
2228 | */ | |
41adf531 | 2229 | __blk_mq_run_dispatch_ops(hctx->queue, false, |
2a904d00 ML |
2230 | need_run = !blk_queue_quiesced(hctx->queue) && |
2231 | blk_mq_hctx_has_pending(hctx)); | |
24f5a90f | 2232 | |
626fb735 | 2233 | if (need_run) |
79f720a7 | 2234 | __blk_mq_delay_run_hw_queue(hctx, async, 0); |
320ae51f | 2235 | } |
5b727272 | 2236 | EXPORT_SYMBOL(blk_mq_run_hw_queue); |
320ae51f | 2237 | |
b6e68ee8 JK |
2238 | /* |
2239 | * Return prefered queue to dispatch from (if any) for non-mq aware IO | |
2240 | * scheduler. | |
2241 | */ | |
2242 | static struct blk_mq_hw_ctx *blk_mq_get_sq_hctx(struct request_queue *q) | |
2243 | { | |
5d05426e | 2244 | struct blk_mq_ctx *ctx = blk_mq_get_ctx(q); |
b6e68ee8 JK |
2245 | /* |
2246 | * If the IO scheduler does not respect hardware queues when | |
2247 | * dispatching, we just don't bother with multiple HW queues and | |
2248 | * dispatch from hctx for the current CPU since running multiple queues | |
2249 | * just causes lock contention inside the scheduler and pointless cache | |
2250 | * bouncing. | |
2251 | */ | |
51ab80f0 | 2252 | struct blk_mq_hw_ctx *hctx = ctx->hctxs[HCTX_TYPE_DEFAULT]; |
5d05426e | 2253 | |
b6e68ee8 JK |
2254 | if (!blk_mq_hctx_stopped(hctx)) |
2255 | return hctx; | |
2256 | return NULL; | |
2257 | } | |
2258 | ||
105663f7 | 2259 | /** |
24f7bb88 | 2260 | * blk_mq_run_hw_queues - Run all hardware queues in a request queue. |
105663f7 AA |
2261 | * @q: Pointer to the request queue to run. |
2262 | * @async: If we want to run the queue asynchronously. | |
2263 | */ | |
b94ec296 | 2264 | void blk_mq_run_hw_queues(struct request_queue *q, bool async) |
320ae51f | 2265 | { |
b6e68ee8 | 2266 | struct blk_mq_hw_ctx *hctx, *sq_hctx; |
4f481208 | 2267 | unsigned long i; |
320ae51f | 2268 | |
b6e68ee8 | 2269 | sq_hctx = NULL; |
4d337ceb | 2270 | if (blk_queue_sq_sched(q)) |
b6e68ee8 | 2271 | sq_hctx = blk_mq_get_sq_hctx(q); |
320ae51f | 2272 | queue_for_each_hw_ctx(q, hctx, i) { |
79f720a7 | 2273 | if (blk_mq_hctx_stopped(hctx)) |
320ae51f | 2274 | continue; |
b6e68ee8 JK |
2275 | /* |
2276 | * Dispatch from this hctx either if there's no hctx preferred | |
2277 | * by IO scheduler or if it has requests that bypass the | |
2278 | * scheduler. | |
2279 | */ | |
2280 | if (!sq_hctx || sq_hctx == hctx || | |
2281 | !list_empty_careful(&hctx->dispatch)) | |
2282 | blk_mq_run_hw_queue(hctx, async); | |
320ae51f JA |
2283 | } |
2284 | } | |
b94ec296 | 2285 | EXPORT_SYMBOL(blk_mq_run_hw_queues); |
320ae51f | 2286 | |
b9151e7b DA |
2287 | /** |
2288 | * blk_mq_delay_run_hw_queues - Run all hardware queues asynchronously. | |
2289 | * @q: Pointer to the request queue to run. | |
fa94ba8a | 2290 | * @msecs: Milliseconds of delay to wait before running the queues. |
b9151e7b DA |
2291 | */ |
2292 | void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs) | |
2293 | { | |
b6e68ee8 | 2294 | struct blk_mq_hw_ctx *hctx, *sq_hctx; |
4f481208 | 2295 | unsigned long i; |
b9151e7b | 2296 | |
b6e68ee8 | 2297 | sq_hctx = NULL; |
4d337ceb | 2298 | if (blk_queue_sq_sched(q)) |
b6e68ee8 | 2299 | sq_hctx = blk_mq_get_sq_hctx(q); |
b9151e7b DA |
2300 | queue_for_each_hw_ctx(q, hctx, i) { |
2301 | if (blk_mq_hctx_stopped(hctx)) | |
2302 | continue; | |
8f5fea65 DJ |
2303 | /* |
2304 | * If there is already a run_work pending, leave the | |
2305 | * pending delay untouched. Otherwise, a hctx can stall | |
2306 | * if another hctx is re-delaying the other's work | |
2307 | * before the work executes. | |
2308 | */ | |
2309 | if (delayed_work_pending(&hctx->run_work)) | |
2310 | continue; | |
b6e68ee8 JK |
2311 | /* |
2312 | * Dispatch from this hctx either if there's no hctx preferred | |
2313 | * by IO scheduler or if it has requests that bypass the | |
2314 | * scheduler. | |
2315 | */ | |
2316 | if (!sq_hctx || sq_hctx == hctx || | |
2317 | !list_empty_careful(&hctx->dispatch)) | |
2318 | blk_mq_delay_run_hw_queue(hctx, msecs); | |
b9151e7b DA |
2319 | } |
2320 | } | |
2321 | EXPORT_SYMBOL(blk_mq_delay_run_hw_queues); | |
2322 | ||
39a70c76 ML |
2323 | /* |
2324 | * This function is often used for pausing .queue_rq() by driver when | |
2325 | * there isn't enough resource or some conditions aren't satisfied, and | |
4d606219 | 2326 | * BLK_STS_RESOURCE is usually returned. |
39a70c76 ML |
2327 | * |
2328 | * We do not guarantee that dispatch can be drained or blocked | |
2329 | * after blk_mq_stop_hw_queue() returns. Please use | |
2330 | * blk_mq_quiesce_queue() for that requirement. | |
2331 | */ | |
2719aa21 JA |
2332 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) |
2333 | { | |
641a9ed6 | 2334 | cancel_delayed_work(&hctx->run_work); |
280d45f6 | 2335 | |
641a9ed6 | 2336 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
2719aa21 | 2337 | } |
641a9ed6 | 2338 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); |
2719aa21 | 2339 | |
39a70c76 ML |
2340 | /* |
2341 | * This function is often used for pausing .queue_rq() by driver when | |
2342 | * there isn't enough resource or some conditions aren't satisfied, and | |
4d606219 | 2343 | * BLK_STS_RESOURCE is usually returned. |
39a70c76 ML |
2344 | * |
2345 | * We do not guarantee that dispatch can be drained or blocked | |
2346 | * after blk_mq_stop_hw_queues() returns. Please use | |
2347 | * blk_mq_quiesce_queue() for that requirement. | |
2348 | */ | |
2719aa21 JA |
2349 | void blk_mq_stop_hw_queues(struct request_queue *q) |
2350 | { | |
641a9ed6 | 2351 | struct blk_mq_hw_ctx *hctx; |
4f481208 | 2352 | unsigned long i; |
641a9ed6 ML |
2353 | |
2354 | queue_for_each_hw_ctx(q, hctx, i) | |
2355 | blk_mq_stop_hw_queue(hctx); | |
280d45f6 CH |
2356 | } |
2357 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
2358 | ||
320ae51f JA |
2359 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
2360 | { | |
2361 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 2362 | |
0ffbce80 | 2363 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
2364 | } |
2365 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
2366 | ||
2f268556 CH |
2367 | void blk_mq_start_hw_queues(struct request_queue *q) |
2368 | { | |
2369 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 2370 | unsigned long i; |
2f268556 CH |
2371 | |
2372 | queue_for_each_hw_ctx(q, hctx, i) | |
2373 | blk_mq_start_hw_queue(hctx); | |
2374 | } | |
2375 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
2376 | ||
ae911c5e JA |
2377 | void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
2378 | { | |
2379 | if (!blk_mq_hctx_stopped(hctx)) | |
2380 | return; | |
2381 | ||
2382 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
2383 | blk_mq_run_hw_queue(hctx, async); | |
2384 | } | |
2385 | EXPORT_SYMBOL_GPL(blk_mq_start_stopped_hw_queue); | |
2386 | ||
1b4a3258 | 2387 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
2388 | { |
2389 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 2390 | unsigned long i; |
320ae51f | 2391 | |
ae911c5e JA |
2392 | queue_for_each_hw_ctx(q, hctx, i) |
2393 | blk_mq_start_stopped_hw_queue(hctx, async); | |
320ae51f JA |
2394 | } |
2395 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
2396 | ||
70f4db63 | 2397 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
2398 | { |
2399 | struct blk_mq_hw_ctx *hctx; | |
2400 | ||
9f993737 | 2401 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
320ae51f | 2402 | |
21c6e939 | 2403 | /* |
15fe8a90 | 2404 | * If we are stopped, don't run the queue. |
21c6e939 | 2405 | */ |
0841031a | 2406 | if (blk_mq_hctx_stopped(hctx)) |
0196d6b4 | 2407 | return; |
7587a5ae BVA |
2408 | |
2409 | __blk_mq_run_hw_queue(hctx); | |
2410 | } | |
2411 | ||
cfd0c552 | 2412 | static inline void __blk_mq_insert_req_list(struct blk_mq_hw_ctx *hctx, |
cfd0c552 ML |
2413 | struct request *rq, |
2414 | bool at_head) | |
320ae51f | 2415 | { |
e57690fe | 2416 | struct blk_mq_ctx *ctx = rq->mq_ctx; |
c16d6b5a | 2417 | enum hctx_type type = hctx->type; |
e57690fe | 2418 | |
7b607814 BVA |
2419 | lockdep_assert_held(&ctx->lock); |
2420 | ||
a54895fa | 2421 | trace_block_rq_insert(rq); |
01b983c9 | 2422 | |
72a0a36e | 2423 | if (at_head) |
c16d6b5a | 2424 | list_add(&rq->queuelist, &ctx->rq_lists[type]); |
72a0a36e | 2425 | else |
c16d6b5a | 2426 | list_add_tail(&rq->queuelist, &ctx->rq_lists[type]); |
cfd0c552 | 2427 | } |
4bb659b1 | 2428 | |
2c3ad667 JA |
2429 | void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, |
2430 | bool at_head) | |
cfd0c552 ML |
2431 | { |
2432 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
2433 | ||
7b607814 BVA |
2434 | lockdep_assert_held(&ctx->lock); |
2435 | ||
e57690fe | 2436 | __blk_mq_insert_req_list(hctx, rq, at_head); |
320ae51f | 2437 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
2438 | } |
2439 | ||
105663f7 AA |
2440 | /** |
2441 | * blk_mq_request_bypass_insert - Insert a request at dispatch list. | |
2442 | * @rq: Pointer to request to be inserted. | |
26bfeb26 | 2443 | * @at_head: true if the request should be inserted at the head of the list. |
105663f7 AA |
2444 | * @run_queue: If we should run the hardware queue after inserting the request. |
2445 | * | |
157f377b JA |
2446 | * Should only be used carefully, when the caller knows we want to |
2447 | * bypass a potential IO scheduler on the target device. | |
2448 | */ | |
01e99aec ML |
2449 | void blk_mq_request_bypass_insert(struct request *rq, bool at_head, |
2450 | bool run_queue) | |
157f377b | 2451 | { |
ea4f995e | 2452 | struct blk_mq_hw_ctx *hctx = rq->mq_hctx; |
157f377b JA |
2453 | |
2454 | spin_lock(&hctx->lock); | |
01e99aec ML |
2455 | if (at_head) |
2456 | list_add(&rq->queuelist, &hctx->dispatch); | |
2457 | else | |
2458 | list_add_tail(&rq->queuelist, &hctx->dispatch); | |
157f377b JA |
2459 | spin_unlock(&hctx->lock); |
2460 | ||
b0850297 ML |
2461 | if (run_queue) |
2462 | blk_mq_run_hw_queue(hctx, false); | |
157f377b JA |
2463 | } |
2464 | ||
bd166ef1 JA |
2465 | void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, |
2466 | struct list_head *list) | |
320ae51f JA |
2467 | |
2468 | { | |
3f0cedc7 | 2469 | struct request *rq; |
c16d6b5a | 2470 | enum hctx_type type = hctx->type; |
3f0cedc7 | 2471 | |
320ae51f JA |
2472 | /* |
2473 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
2474 | * offline now | |
2475 | */ | |
3f0cedc7 | 2476 | list_for_each_entry(rq, list, queuelist) { |
e57690fe | 2477 | BUG_ON(rq->mq_ctx != ctx); |
a54895fa | 2478 | trace_block_rq_insert(rq); |
320ae51f | 2479 | } |
3f0cedc7 ML |
2480 | |
2481 | spin_lock(&ctx->lock); | |
c16d6b5a | 2482 | list_splice_tail_init(list, &ctx->rq_lists[type]); |
cfd0c552 | 2483 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f | 2484 | spin_unlock(&ctx->lock); |
320ae51f JA |
2485 | } |
2486 | ||
dc5fc361 JA |
2487 | static void blk_mq_commit_rqs(struct blk_mq_hw_ctx *hctx, int *queued, |
2488 | bool from_schedule) | |
320ae51f | 2489 | { |
dc5fc361 JA |
2490 | if (hctx->queue->mq_ops->commit_rqs) { |
2491 | trace_block_unplug(hctx->queue, *queued, !from_schedule); | |
2492 | hctx->queue->mq_ops->commit_rqs(hctx); | |
2493 | } | |
2494 | *queued = 0; | |
2495 | } | |
320ae51f | 2496 | |
14ccb66b CH |
2497 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio, |
2498 | unsigned int nr_segs) | |
320ae51f | 2499 | { |
93f221ae EB |
2500 | int err; |
2501 | ||
f924cdde CH |
2502 | if (bio->bi_opf & REQ_RAHEAD) |
2503 | rq->cmd_flags |= REQ_FAILFAST_MASK; | |
2504 | ||
2505 | rq->__sector = bio->bi_iter.bi_sector; | |
14ccb66b | 2506 | blk_rq_bio_prep(rq, bio, nr_segs); |
93f221ae EB |
2507 | |
2508 | /* This can't fail, since GFP_NOIO includes __GFP_DIRECT_RECLAIM. */ | |
2509 | err = blk_crypto_rq_bio_prep(rq, bio, GFP_NOIO); | |
2510 | WARN_ON_ONCE(err); | |
4b570521 | 2511 | |
b5af37ab | 2512 | blk_account_io_start(rq); |
320ae51f JA |
2513 | } |
2514 | ||
0f95549c | 2515 | static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx, |
3e08773c | 2516 | struct request *rq, bool last) |
f984df1f | 2517 | { |
f984df1f | 2518 | struct request_queue *q = rq->q; |
f984df1f SL |
2519 | struct blk_mq_queue_data bd = { |
2520 | .rq = rq, | |
be94f058 | 2521 | .last = last, |
f984df1f | 2522 | }; |
f06345ad | 2523 | blk_status_t ret; |
0f95549c | 2524 | |
0f95549c MS |
2525 | /* |
2526 | * For OK queue, we are done. For error, caller may kill it. | |
2527 | * Any other error (busy), just add it to our list as we | |
2528 | * previously would have done. | |
2529 | */ | |
2530 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
2531 | switch (ret) { | |
2532 | case BLK_STS_OK: | |
6ce3dd6e | 2533 | blk_mq_update_dispatch_busy(hctx, false); |
0f95549c MS |
2534 | break; |
2535 | case BLK_STS_RESOURCE: | |
86ff7c2a | 2536 | case BLK_STS_DEV_RESOURCE: |
6ce3dd6e | 2537 | blk_mq_update_dispatch_busy(hctx, true); |
0f95549c MS |
2538 | __blk_mq_requeue_request(rq); |
2539 | break; | |
2540 | default: | |
6ce3dd6e | 2541 | blk_mq_update_dispatch_busy(hctx, false); |
0f95549c MS |
2542 | break; |
2543 | } | |
2544 | ||
2545 | return ret; | |
2546 | } | |
2547 | ||
fd9c40f6 | 2548 | static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, |
0f95549c | 2549 | struct request *rq, |
fd9c40f6 | 2550 | bool bypass_insert, bool last) |
0f95549c MS |
2551 | { |
2552 | struct request_queue *q = rq->q; | |
d964f04a | 2553 | bool run_queue = true; |
2a5a24aa | 2554 | int budget_token; |
d964f04a | 2555 | |
23d4ee19 | 2556 | /* |
fd9c40f6 | 2557 | * RCU or SRCU read lock is needed before checking quiesced flag. |
23d4ee19 | 2558 | * |
fd9c40f6 BVA |
2559 | * When queue is stopped or quiesced, ignore 'bypass_insert' from |
2560 | * blk_mq_request_issue_directly(), and return BLK_STS_OK to caller, | |
2561 | * and avoid driver to try to dispatch again. | |
23d4ee19 | 2562 | */ |
fd9c40f6 | 2563 | if (blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q)) { |
d964f04a | 2564 | run_queue = false; |
fd9c40f6 BVA |
2565 | bypass_insert = false; |
2566 | goto insert; | |
d964f04a | 2567 | } |
f984df1f | 2568 | |
2ff0682d | 2569 | if ((rq->rq_flags & RQF_ELV) && !bypass_insert) |
fd9c40f6 | 2570 | goto insert; |
2253efc8 | 2571 | |
2a5a24aa ML |
2572 | budget_token = blk_mq_get_dispatch_budget(q); |
2573 | if (budget_token < 0) | |
fd9c40f6 | 2574 | goto insert; |
bd166ef1 | 2575 | |
2a5a24aa ML |
2576 | blk_mq_set_rq_budget_token(rq, budget_token); |
2577 | ||
8ab6bb9e | 2578 | if (!blk_mq_get_driver_tag(rq)) { |
2a5a24aa | 2579 | blk_mq_put_dispatch_budget(q, budget_token); |
fd9c40f6 | 2580 | goto insert; |
88022d72 | 2581 | } |
de148297 | 2582 | |
3e08773c | 2583 | return __blk_mq_issue_directly(hctx, rq, last); |
fd9c40f6 BVA |
2584 | insert: |
2585 | if (bypass_insert) | |
2586 | return BLK_STS_RESOURCE; | |
2587 | ||
db03f88f ML |
2588 | blk_mq_sched_insert_request(rq, false, run_queue, false); |
2589 | ||
fd9c40f6 BVA |
2590 | return BLK_STS_OK; |
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 | { |
2a904d00 ML |
2606 | blk_status_t ret = |
2607 | __blk_mq_try_issue_directly(hctx, rq, false, true); | |
fd9c40f6 | 2608 | |
fd9c40f6 | 2609 | if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) |
01e99aec | 2610 | blk_mq_request_bypass_insert(rq, false, true); |
fd9c40f6 BVA |
2611 | else if (ret != BLK_STS_OK) |
2612 | blk_mq_end_request(rq, ret); | |
fd9c40f6 BVA |
2613 | } |
2614 | ||
06c8c691 | 2615 | static blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last) |
fd9c40f6 | 2616 | { |
4cafe86c | 2617 | return __blk_mq_try_issue_directly(rq->mq_hctx, rq, true, last); |
5eb6126e CH |
2618 | } |
2619 | ||
b84c5b50 CH |
2620 | static void blk_mq_plug_issue_direct(struct blk_plug *plug, bool from_schedule) |
2621 | { | |
2622 | struct blk_mq_hw_ctx *hctx = NULL; | |
2623 | struct request *rq; | |
2624 | int queued = 0; | |
2625 | int errors = 0; | |
2626 | ||
2627 | while ((rq = rq_list_pop(&plug->mq_list))) { | |
2628 | bool last = rq_list_empty(plug->mq_list); | |
2629 | blk_status_t ret; | |
2630 | ||
2631 | if (hctx != rq->mq_hctx) { | |
2632 | if (hctx) | |
2633 | blk_mq_commit_rqs(hctx, &queued, from_schedule); | |
2634 | hctx = rq->mq_hctx; | |
2635 | } | |
2636 | ||
2637 | ret = blk_mq_request_issue_directly(rq, last); | |
2638 | switch (ret) { | |
2639 | case BLK_STS_OK: | |
2640 | queued++; | |
2641 | break; | |
2642 | case BLK_STS_RESOURCE: | |
2643 | case BLK_STS_DEV_RESOURCE: | |
d3b38596 | 2644 | blk_mq_request_bypass_insert(rq, false, true); |
b84c5b50 CH |
2645 | blk_mq_commit_rqs(hctx, &queued, from_schedule); |
2646 | return; | |
2647 | default: | |
2648 | blk_mq_end_request(rq, ret); | |
2649 | errors++; | |
2650 | break; | |
2651 | } | |
2652 | } | |
2653 | ||
2654 | /* | |
2655 | * If we didn't flush the entire list, we could have told the driver | |
2656 | * there was more coming, but that turned out to be a lie. | |
2657 | */ | |
2658 | if (errors) | |
2659 | blk_mq_commit_rqs(hctx, &queued, from_schedule); | |
2660 | } | |
2661 | ||
518579a9 KB |
2662 | static void __blk_mq_flush_plug_list(struct request_queue *q, |
2663 | struct blk_plug *plug) | |
2664 | { | |
2665 | if (blk_queue_quiesced(q)) | |
2666 | return; | |
2667 | q->mq_ops->queue_rqs(&plug->mq_list); | |
2668 | } | |
2669 | ||
26fed4ac JA |
2670 | static void blk_mq_dispatch_plug_list(struct blk_plug *plug, bool from_sched) |
2671 | { | |
2672 | struct blk_mq_hw_ctx *this_hctx = NULL; | |
2673 | struct blk_mq_ctx *this_ctx = NULL; | |
2674 | struct request *requeue_list = NULL; | |
2675 | unsigned int depth = 0; | |
2676 | LIST_HEAD(list); | |
2677 | ||
2678 | do { | |
2679 | struct request *rq = rq_list_pop(&plug->mq_list); | |
2680 | ||
2681 | if (!this_hctx) { | |
2682 | this_hctx = rq->mq_hctx; | |
2683 | this_ctx = rq->mq_ctx; | |
2684 | } else if (this_hctx != rq->mq_hctx || this_ctx != rq->mq_ctx) { | |
2685 | rq_list_add(&requeue_list, rq); | |
2686 | continue; | |
2687 | } | |
2688 | list_add_tail(&rq->queuelist, &list); | |
2689 | depth++; | |
2690 | } while (!rq_list_empty(plug->mq_list)); | |
2691 | ||
2692 | plug->mq_list = requeue_list; | |
2693 | trace_block_unplug(this_hctx->queue, depth, !from_sched); | |
2694 | blk_mq_sched_insert_requests(this_hctx, this_ctx, &list, from_sched); | |
2695 | } | |
2696 | ||
b84c5b50 CH |
2697 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) |
2698 | { | |
3c67d44d | 2699 | struct request *rq; |
b84c5b50 CH |
2700 | |
2701 | if (rq_list_empty(plug->mq_list)) | |
2702 | return; | |
2703 | plug->rq_count = 0; | |
2704 | ||
2705 | if (!plug->multiple_queues && !plug->has_elevator && !from_schedule) { | |
3c67d44d JA |
2706 | struct request_queue *q; |
2707 | ||
2708 | rq = rq_list_peek(&plug->mq_list); | |
2709 | q = rq->q; | |
2710 | ||
2711 | /* | |
2712 | * Peek first request and see if we have a ->queue_rqs() hook. | |
2713 | * If we do, we can dispatch the whole plug list in one go. We | |
2714 | * already know at this point that all requests belong to the | |
2715 | * same queue, caller must ensure that's the case. | |
2716 | * | |
2717 | * Since we pass off the full list to the driver at this point, | |
2718 | * we do not increment the active request count for the queue. | |
2719 | * Bypass shared tags for now because of that. | |
2720 | */ | |
2721 | if (q->mq_ops->queue_rqs && | |
2722 | !(rq->mq_hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) { | |
2723 | blk_mq_run_dispatch_ops(q, | |
518579a9 | 2724 | __blk_mq_flush_plug_list(q, plug)); |
3c67d44d JA |
2725 | if (rq_list_empty(plug->mq_list)) |
2726 | return; | |
2727 | } | |
73f3760e ML |
2728 | |
2729 | blk_mq_run_dispatch_ops(q, | |
4cafe86c | 2730 | blk_mq_plug_issue_direct(plug, false)); |
b84c5b50 CH |
2731 | if (rq_list_empty(plug->mq_list)) |
2732 | return; | |
2733 | } | |
2734 | ||
b84c5b50 | 2735 | do { |
26fed4ac | 2736 | blk_mq_dispatch_plug_list(plug, from_schedule); |
b84c5b50 | 2737 | } while (!rq_list_empty(plug->mq_list)); |
b84c5b50 CH |
2738 | } |
2739 | ||
6ce3dd6e ML |
2740 | void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, |
2741 | struct list_head *list) | |
2742 | { | |
536167d4 | 2743 | int queued = 0; |
632bfb63 | 2744 | int errors = 0; |
536167d4 | 2745 | |
6ce3dd6e | 2746 | while (!list_empty(list)) { |
fd9c40f6 | 2747 | blk_status_t ret; |
6ce3dd6e ML |
2748 | struct request *rq = list_first_entry(list, struct request, |
2749 | queuelist); | |
2750 | ||
2751 | list_del_init(&rq->queuelist); | |
fd9c40f6 BVA |
2752 | ret = blk_mq_request_issue_directly(rq, list_empty(list)); |
2753 | if (ret != BLK_STS_OK) { | |
65fac0d5 | 2754 | errors++; |
fd9c40f6 BVA |
2755 | if (ret == BLK_STS_RESOURCE || |
2756 | ret == BLK_STS_DEV_RESOURCE) { | |
01e99aec | 2757 | blk_mq_request_bypass_insert(rq, false, |
c616cbee | 2758 | list_empty(list)); |
fd9c40f6 BVA |
2759 | break; |
2760 | } | |
2761 | blk_mq_end_request(rq, ret); | |
536167d4 KB |
2762 | } else |
2763 | queued++; | |
6ce3dd6e | 2764 | } |
d666ba98 JA |
2765 | |
2766 | /* | |
2767 | * If we didn't flush the entire list, we could have told | |
2768 | * the driver there was more coming, but that turned out to | |
2769 | * be a lie. | |
2770 | */ | |
632bfb63 | 2771 | if ((!list_empty(list) || errors) && |
2772 | hctx->queue->mq_ops->commit_rqs && queued) | |
d666ba98 | 2773 | hctx->queue->mq_ops->commit_rqs(hctx); |
6ce3dd6e ML |
2774 | } |
2775 | ||
b131f201 | 2776 | static bool blk_mq_attempt_bio_merge(struct request_queue *q, |
0c5bcc92 | 2777 | struct bio *bio, unsigned int nr_segs) |
900e0807 JA |
2778 | { |
2779 | if (!blk_queue_nomerges(q) && bio_mergeable(bio)) { | |
0c5bcc92 | 2780 | if (blk_attempt_plug_merge(q, bio, nr_segs)) |
900e0807 JA |
2781 | return true; |
2782 | if (blk_mq_sched_bio_merge(q, bio, nr_segs)) | |
2783 | return true; | |
2784 | } | |
2785 | return false; | |
2786 | } | |
2787 | ||
71539717 JA |
2788 | static struct request *blk_mq_get_new_requests(struct request_queue *q, |
2789 | struct blk_plug *plug, | |
0a5aa8d1 SK |
2790 | struct bio *bio, |
2791 | unsigned int nsegs) | |
71539717 JA |
2792 | { |
2793 | struct blk_mq_alloc_data data = { | |
2794 | .q = q, | |
2795 | .nr_tags = 1, | |
9d497e29 | 2796 | .cmd_flags = bio->bi_opf, |
71539717 JA |
2797 | }; |
2798 | struct request *rq; | |
2799 | ||
5b13bc8a | 2800 | if (unlikely(bio_queue_enter(bio))) |
b637108a | 2801 | return NULL; |
900e0807 | 2802 | |
0a5aa8d1 SK |
2803 | if (blk_mq_attempt_bio_merge(q, bio, nsegs)) |
2804 | goto queue_exit; | |
2805 | ||
2806 | rq_qos_throttle(q, bio); | |
2807 | ||
71539717 JA |
2808 | if (plug) { |
2809 | data.nr_tags = plug->nr_ios; | |
2810 | plug->nr_ios = 1; | |
2811 | data.cached_rq = &plug->cached_rq; | |
2812 | } | |
2813 | ||
2814 | rq = __blk_mq_alloc_requests(&data); | |
373b5416 JA |
2815 | if (rq) |
2816 | return rq; | |
71539717 JA |
2817 | rq_qos_cleanup(q, bio); |
2818 | if (bio->bi_opf & REQ_NOWAIT) | |
2819 | bio_wouldblock_error(bio); | |
0a5aa8d1 | 2820 | queue_exit: |
5b13bc8a | 2821 | blk_queue_exit(q); |
71539717 JA |
2822 | return NULL; |
2823 | } | |
2824 | ||
5b13bc8a | 2825 | static inline struct request *blk_mq_get_cached_request(struct request_queue *q, |
0a5aa8d1 | 2826 | struct blk_plug *plug, struct bio **bio, unsigned int nsegs) |
71539717 | 2827 | { |
b637108a | 2828 | struct request *rq; |
b637108a | 2829 | |
5b13bc8a CH |
2830 | if (!plug) |
2831 | return NULL; | |
2832 | rq = rq_list_peek(&plug->cached_rq); | |
2833 | if (!rq || rq->q != q) | |
2834 | return NULL; | |
71539717 | 2835 | |
0a5aa8d1 SK |
2836 | if (blk_mq_attempt_bio_merge(q, *bio, nsegs)) { |
2837 | *bio = NULL; | |
2838 | return NULL; | |
2839 | } | |
2840 | ||
0a5aa8d1 | 2841 | if (blk_mq_get_hctx_type((*bio)->bi_opf) != rq->mq_hctx->type) |
5b13bc8a | 2842 | return NULL; |
0a5aa8d1 | 2843 | if (op_is_flush(rq->cmd_flags) != op_is_flush((*bio)->bi_opf)) |
5b13bc8a CH |
2844 | return NULL; |
2845 | ||
2645672f JA |
2846 | /* |
2847 | * If any qos ->throttle() end up blocking, we will have flushed the | |
2848 | * plug and hence killed the cached_rq list as well. Pop this entry | |
2849 | * before we throttle. | |
2850 | */ | |
5b13bc8a | 2851 | plug->cached_rq = rq_list_next(rq); |
2645672f JA |
2852 | rq_qos_throttle(q, *bio); |
2853 | ||
2854 | rq->cmd_flags = (*bio)->bi_opf; | |
5b13bc8a | 2855 | INIT_LIST_HEAD(&rq->queuelist); |
5b13bc8a | 2856 | return rq; |
71539717 JA |
2857 | } |
2858 | ||
82b74cac JK |
2859 | static void bio_set_ioprio(struct bio *bio) |
2860 | { | |
a78418e6 JK |
2861 | /* Nobody set ioprio so far? Initialize it based on task's nice value */ |
2862 | if (IOPRIO_PRIO_CLASS(bio->bi_ioprio) == IOPRIO_CLASS_NONE) | |
2863 | bio->bi_ioprio = get_current_ioprio(); | |
82b74cac JK |
2864 | blkcg_set_ioprio(bio); |
2865 | } | |
2866 | ||
105663f7 | 2867 | /** |
c62b37d9 | 2868 | * blk_mq_submit_bio - Create and send a request to block device. |
105663f7 AA |
2869 | * @bio: Bio pointer. |
2870 | * | |
2871 | * Builds up a request structure from @q and @bio and send to the device. The | |
2872 | * request may not be queued directly to hardware if: | |
2873 | * * This request can be merged with another one | |
2874 | * * We want to place request at plug queue for possible future merging | |
2875 | * * There is an IO scheduler active at this queue | |
2876 | * | |
2877 | * It will not queue the request if there is an error with the bio, or at the | |
2878 | * request creation. | |
105663f7 | 2879 | */ |
3e08773c | 2880 | void blk_mq_submit_bio(struct bio *bio) |
07068d5b | 2881 | { |
ed6cddef | 2882 | struct request_queue *q = bdev_get_queue(bio->bi_bdev); |
6deacb3b | 2883 | struct blk_plug *plug = blk_mq_plug(bio); |
ef295ecf | 2884 | const int is_sync = op_is_sync(bio->bi_opf); |
07068d5b | 2885 | struct request *rq; |
abd45c15 | 2886 | unsigned int nr_segs = 1; |
a892c8d5 | 2887 | blk_status_t ret; |
07068d5b | 2888 | |
51d798cd | 2889 | bio = blk_queue_bounce(bio, q); |
c55ddd90 CH |
2890 | if (bio_may_exceed_limits(bio, &q->limits)) |
2891 | bio = __bio_split_to_limits(bio, &q->limits, &nr_segs); | |
f36ea50c | 2892 | |
e23947bd | 2893 | if (!bio_integrity_prep(bio)) |
900e0807 | 2894 | return; |
87760e5e | 2895 | |
9c6227e0 JK |
2896 | bio_set_ioprio(bio); |
2897 | ||
0a5aa8d1 | 2898 | rq = blk_mq_get_cached_request(q, plug, &bio, nr_segs); |
5b13bc8a | 2899 | if (!rq) { |
0a5aa8d1 SK |
2900 | if (!bio) |
2901 | return; | |
2902 | rq = blk_mq_get_new_requests(q, plug, bio, nr_segs); | |
5b13bc8a CH |
2903 | if (unlikely(!rq)) |
2904 | return; | |
2905 | } | |
87760e5e | 2906 | |
e8a676d6 | 2907 | trace_block_getrq(bio); |
d6f1dda2 | 2908 | |
c1c80384 | 2909 | rq_qos_track(q, rq, bio); |
07068d5b | 2910 | |
970d168d BVA |
2911 | blk_mq_bio_to_request(rq, bio, nr_segs); |
2912 | ||
a892c8d5 ST |
2913 | ret = blk_crypto_init_request(rq); |
2914 | if (ret != BLK_STS_OK) { | |
2915 | bio->bi_status = ret; | |
2916 | bio_endio(bio); | |
2917 | blk_mq_free_request(rq); | |
3e08773c | 2918 | return; |
a892c8d5 ST |
2919 | } |
2920 | ||
2b504bd4 ML |
2921 | if (op_is_flush(bio->bi_opf)) { |
2922 | blk_insert_flush(rq); | |
d92ca9d8 | 2923 | return; |
2b504bd4 | 2924 | } |
d92ca9d8 | 2925 | |
1e9c2303 | 2926 | if (plug) |
ce5b009c | 2927 | blk_add_rq_to_plug(plug, rq); |
1e9c2303 CH |
2928 | else if ((rq->rq_flags & RQF_ELV) || |
2929 | (rq->mq_hctx->dispatch_busy && | |
2930 | (q->nr_hw_queues == 1 || !is_sync))) | |
a12de1d4 | 2931 | blk_mq_sched_insert_request(rq, false, true, true); |
1e9c2303 | 2932 | else |
bcc330f4 | 2933 | blk_mq_run_dispatch_ops(rq->q, |
2a904d00 | 2934 | blk_mq_try_issue_directly(rq->mq_hctx, rq)); |
320ae51f JA |
2935 | } |
2936 | ||
248c7933 | 2937 | #ifdef CONFIG_BLK_MQ_STACKING |
06c8c691 | 2938 | /** |
a5efda3c | 2939 | * blk_insert_cloned_request - Helper for stacking drivers to submit a request |
a5efda3c | 2940 | * @rq: the request being queued |
06c8c691 | 2941 | */ |
28db4711 | 2942 | blk_status_t blk_insert_cloned_request(struct request *rq) |
06c8c691 | 2943 | { |
28db4711 | 2944 | struct request_queue *q = rq->q; |
06c8c691 | 2945 | unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(rq)); |
a5efda3c | 2946 | blk_status_t ret; |
06c8c691 CH |
2947 | |
2948 | if (blk_rq_sectors(rq) > max_sectors) { | |
2949 | /* | |
2950 | * SCSI device does not have a good way to return if | |
2951 | * Write Same/Zero is actually supported. If a device rejects | |
2952 | * a non-read/write command (discard, write same,etc.) the | |
2953 | * low-level device driver will set the relevant queue limit to | |
2954 | * 0 to prevent blk-lib from issuing more of the offending | |
2955 | * operations. Commands queued prior to the queue limit being | |
2956 | * reset need to be completed with BLK_STS_NOTSUPP to avoid I/O | |
2957 | * errors being propagated to upper layers. | |
2958 | */ | |
2959 | if (max_sectors == 0) | |
2960 | return BLK_STS_NOTSUPP; | |
2961 | ||
2962 | printk(KERN_ERR "%s: over max size limit. (%u > %u)\n", | |
2963 | __func__, blk_rq_sectors(rq), max_sectors); | |
2964 | return BLK_STS_IOERR; | |
2965 | } | |
2966 | ||
2967 | /* | |
2968 | * The queue settings related to segment counting may differ from the | |
2969 | * original queue. | |
2970 | */ | |
2971 | rq->nr_phys_segments = blk_recalc_rq_segments(rq); | |
2972 | if (rq->nr_phys_segments > queue_max_segments(q)) { | |
2973 | printk(KERN_ERR "%s: over max segments limit. (%hu > %hu)\n", | |
2974 | __func__, rq->nr_phys_segments, queue_max_segments(q)); | |
2975 | return BLK_STS_IOERR; | |
2976 | } | |
2977 | ||
28db4711 | 2978 | if (q->disk && should_fail_request(q->disk->part0, blk_rq_bytes(rq))) |
06c8c691 CH |
2979 | return BLK_STS_IOERR; |
2980 | ||
2981 | if (blk_crypto_insert_cloned_request(rq)) | |
2982 | return BLK_STS_IOERR; | |
2983 | ||
2984 | blk_account_io_start(rq); | |
2985 | ||
2986 | /* | |
2987 | * Since we have a scheduler attached on the top device, | |
2988 | * bypass a potential scheduler on the bottom device for | |
2989 | * insert. | |
2990 | */ | |
28db4711 | 2991 | blk_mq_run_dispatch_ops(q, |
4cafe86c | 2992 | ret = blk_mq_request_issue_directly(rq, true)); |
592ee119 YK |
2993 | if (ret) |
2994 | blk_account_io_done(rq, ktime_get_ns()); | |
4cafe86c | 2995 | return ret; |
06c8c691 CH |
2996 | } |
2997 | EXPORT_SYMBOL_GPL(blk_insert_cloned_request); | |
2998 | ||
2999 | /** | |
3000 | * blk_rq_unprep_clone - Helper function to free all bios in a cloned request | |
3001 | * @rq: the clone request to be cleaned up | |
3002 | * | |
3003 | * Description: | |
3004 | * Free all bios in @rq for a cloned request. | |
3005 | */ | |
3006 | void blk_rq_unprep_clone(struct request *rq) | |
3007 | { | |
3008 | struct bio *bio; | |
3009 | ||
3010 | while ((bio = rq->bio) != NULL) { | |
3011 | rq->bio = bio->bi_next; | |
3012 | ||
3013 | bio_put(bio); | |
3014 | } | |
3015 | } | |
3016 | EXPORT_SYMBOL_GPL(blk_rq_unprep_clone); | |
3017 | ||
3018 | /** | |
3019 | * blk_rq_prep_clone - Helper function to setup clone request | |
3020 | * @rq: the request to be setup | |
3021 | * @rq_src: original request to be cloned | |
3022 | * @bs: bio_set that bios for clone are allocated from | |
3023 | * @gfp_mask: memory allocation mask for bio | |
3024 | * @bio_ctr: setup function to be called for each clone bio. | |
3025 | * Returns %0 for success, non %0 for failure. | |
3026 | * @data: private data to be passed to @bio_ctr | |
3027 | * | |
3028 | * Description: | |
3029 | * Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq. | |
3030 | * Also, pages which the original bios are pointing to are not copied | |
3031 | * and the cloned bios just point same pages. | |
3032 | * So cloned bios must be completed before original bios, which means | |
3033 | * the caller must complete @rq before @rq_src. | |
3034 | */ | |
3035 | int blk_rq_prep_clone(struct request *rq, struct request *rq_src, | |
3036 | struct bio_set *bs, gfp_t gfp_mask, | |
3037 | int (*bio_ctr)(struct bio *, struct bio *, void *), | |
3038 | void *data) | |
3039 | { | |
3040 | struct bio *bio, *bio_src; | |
3041 | ||
3042 | if (!bs) | |
3043 | bs = &fs_bio_set; | |
3044 | ||
3045 | __rq_for_each_bio(bio_src, rq_src) { | |
abfc426d CH |
3046 | bio = bio_alloc_clone(rq->q->disk->part0, bio_src, gfp_mask, |
3047 | bs); | |
06c8c691 CH |
3048 | if (!bio) |
3049 | goto free_and_out; | |
3050 | ||
3051 | if (bio_ctr && bio_ctr(bio, bio_src, data)) | |
3052 | goto free_and_out; | |
3053 | ||
3054 | if (rq->bio) { | |
3055 | rq->biotail->bi_next = bio; | |
3056 | rq->biotail = bio; | |
3057 | } else { | |
3058 | rq->bio = rq->biotail = bio; | |
3059 | } | |
3060 | bio = NULL; | |
3061 | } | |
3062 | ||
3063 | /* Copy attributes of the original request to the clone request. */ | |
3064 | rq->__sector = blk_rq_pos(rq_src); | |
3065 | rq->__data_len = blk_rq_bytes(rq_src); | |
3066 | if (rq_src->rq_flags & RQF_SPECIAL_PAYLOAD) { | |
3067 | rq->rq_flags |= RQF_SPECIAL_PAYLOAD; | |
3068 | rq->special_vec = rq_src->special_vec; | |
3069 | } | |
3070 | rq->nr_phys_segments = rq_src->nr_phys_segments; | |
3071 | rq->ioprio = rq_src->ioprio; | |
3072 | ||
3073 | if (rq->bio && blk_crypto_rq_bio_prep(rq, rq->bio, gfp_mask) < 0) | |
3074 | goto free_and_out; | |
3075 | ||
3076 | return 0; | |
3077 | ||
3078 | free_and_out: | |
3079 | if (bio) | |
3080 | bio_put(bio); | |
3081 | blk_rq_unprep_clone(rq); | |
3082 | ||
3083 | return -ENOMEM; | |
3084 | } | |
3085 | EXPORT_SYMBOL_GPL(blk_rq_prep_clone); | |
248c7933 | 3086 | #endif /* CONFIG_BLK_MQ_STACKING */ |
06c8c691 | 3087 | |
f2b8f3ce CH |
3088 | /* |
3089 | * Steal bios from a request and add them to a bio list. | |
3090 | * The request must not have been partially completed before. | |
3091 | */ | |
3092 | void blk_steal_bios(struct bio_list *list, struct request *rq) | |
3093 | { | |
3094 | if (rq->bio) { | |
3095 | if (list->tail) | |
3096 | list->tail->bi_next = rq->bio; | |
3097 | else | |
3098 | list->head = rq->bio; | |
3099 | list->tail = rq->biotail; | |
3100 | ||
3101 | rq->bio = NULL; | |
3102 | rq->biotail = NULL; | |
3103 | } | |
3104 | ||
3105 | rq->__data_len = 0; | |
3106 | } | |
3107 | EXPORT_SYMBOL_GPL(blk_steal_bios); | |
3108 | ||
bd63141d ML |
3109 | static size_t order_to_size(unsigned int order) |
3110 | { | |
3111 | return (size_t)PAGE_SIZE << order; | |
3112 | } | |
3113 | ||
3114 | /* called before freeing request pool in @tags */ | |
f32e4eaf JG |
3115 | static void blk_mq_clear_rq_mapping(struct blk_mq_tags *drv_tags, |
3116 | struct blk_mq_tags *tags) | |
bd63141d | 3117 | { |
bd63141d ML |
3118 | struct page *page; |
3119 | unsigned long flags; | |
3120 | ||
76dd2980 YK |
3121 | /* |
3122 | * There is no need to clear mapping if driver tags is not initialized | |
3123 | * or the mapping belongs to the driver tags. | |
3124 | */ | |
3125 | if (!drv_tags || drv_tags == tags) | |
4f245d5b JG |
3126 | return; |
3127 | ||
bd63141d ML |
3128 | list_for_each_entry(page, &tags->page_list, lru) { |
3129 | unsigned long start = (unsigned long)page_address(page); | |
3130 | unsigned long end = start + order_to_size(page->private); | |
3131 | int i; | |
3132 | ||
f32e4eaf | 3133 | for (i = 0; i < drv_tags->nr_tags; i++) { |
bd63141d ML |
3134 | struct request *rq = drv_tags->rqs[i]; |
3135 | unsigned long rq_addr = (unsigned long)rq; | |
3136 | ||
3137 | if (rq_addr >= start && rq_addr < end) { | |
0a467d0f | 3138 | WARN_ON_ONCE(req_ref_read(rq) != 0); |
bd63141d ML |
3139 | cmpxchg(&drv_tags->rqs[i], rq, NULL); |
3140 | } | |
3141 | } | |
3142 | } | |
3143 | ||
3144 | /* | |
3145 | * Wait until all pending iteration is done. | |
3146 | * | |
3147 | * Request reference is cleared and it is guaranteed to be observed | |
3148 | * after the ->lock is released. | |
3149 | */ | |
3150 | spin_lock_irqsave(&drv_tags->lock, flags); | |
3151 | spin_unlock_irqrestore(&drv_tags->lock, flags); | |
3152 | } | |
3153 | ||
cc71a6f4 JA |
3154 | void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, |
3155 | unsigned int hctx_idx) | |
95363efd | 3156 | { |
f32e4eaf | 3157 | struct blk_mq_tags *drv_tags; |
e9b267d9 | 3158 | struct page *page; |
320ae51f | 3159 | |
e02657ea ML |
3160 | if (list_empty(&tags->page_list)) |
3161 | return; | |
3162 | ||
079a2e3e JG |
3163 | if (blk_mq_is_shared_tags(set->flags)) |
3164 | drv_tags = set->shared_tags; | |
e155b0c2 JG |
3165 | else |
3166 | drv_tags = set->tags[hctx_idx]; | |
f32e4eaf | 3167 | |
65de57bb | 3168 | if (tags->static_rqs && set->ops->exit_request) { |
e9b267d9 | 3169 | int i; |
320ae51f | 3170 | |
24d2f903 | 3171 | for (i = 0; i < tags->nr_tags; i++) { |
2af8cbe3 JA |
3172 | struct request *rq = tags->static_rqs[i]; |
3173 | ||
3174 | if (!rq) | |
e9b267d9 | 3175 | continue; |
d6296d39 | 3176 | set->ops->exit_request(set, rq, hctx_idx); |
2af8cbe3 | 3177 | tags->static_rqs[i] = NULL; |
e9b267d9 | 3178 | } |
320ae51f | 3179 | } |
320ae51f | 3180 | |
f32e4eaf | 3181 | blk_mq_clear_rq_mapping(drv_tags, tags); |
bd63141d | 3182 | |
24d2f903 CH |
3183 | while (!list_empty(&tags->page_list)) { |
3184 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 3185 | list_del_init(&page->lru); |
f75782e4 CM |
3186 | /* |
3187 | * Remove kmemleak object previously allocated in | |
273938bf | 3188 | * blk_mq_alloc_rqs(). |
f75782e4 CM |
3189 | */ |
3190 | kmemleak_free(page_address(page)); | |
320ae51f JA |
3191 | __free_pages(page, page->private); |
3192 | } | |
cc71a6f4 | 3193 | } |
320ae51f | 3194 | |
e155b0c2 | 3195 | void blk_mq_free_rq_map(struct blk_mq_tags *tags) |
cc71a6f4 | 3196 | { |
24d2f903 | 3197 | kfree(tags->rqs); |
cc71a6f4 | 3198 | tags->rqs = NULL; |
2af8cbe3 JA |
3199 | kfree(tags->static_rqs); |
3200 | tags->static_rqs = NULL; | |
320ae51f | 3201 | |
e155b0c2 | 3202 | blk_mq_free_tags(tags); |
320ae51f JA |
3203 | } |
3204 | ||
4d805131 ML |
3205 | static enum hctx_type hctx_idx_to_type(struct blk_mq_tag_set *set, |
3206 | unsigned int hctx_idx) | |
3207 | { | |
3208 | int i; | |
3209 | ||
3210 | for (i = 0; i < set->nr_maps; i++) { | |
3211 | unsigned int start = set->map[i].queue_offset; | |
3212 | unsigned int end = start + set->map[i].nr_queues; | |
3213 | ||
3214 | if (hctx_idx >= start && hctx_idx < end) | |
3215 | break; | |
3216 | } | |
3217 | ||
3218 | if (i >= set->nr_maps) | |
3219 | i = HCTX_TYPE_DEFAULT; | |
3220 | ||
3221 | return i; | |
3222 | } | |
3223 | ||
3224 | static int blk_mq_get_hctx_node(struct blk_mq_tag_set *set, | |
3225 | unsigned int hctx_idx) | |
3226 | { | |
3227 | enum hctx_type type = hctx_idx_to_type(set, hctx_idx); | |
3228 | ||
3229 | return blk_mq_hw_queue_to_node(&set->map[type], hctx_idx); | |
3230 | } | |
3231 | ||
63064be1 JG |
3232 | static struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set, |
3233 | unsigned int hctx_idx, | |
3234 | unsigned int nr_tags, | |
e155b0c2 | 3235 | unsigned int reserved_tags) |
320ae51f | 3236 | { |
4d805131 | 3237 | int node = blk_mq_get_hctx_node(set, hctx_idx); |
24d2f903 | 3238 | struct blk_mq_tags *tags; |
320ae51f | 3239 | |
59f082e4 SL |
3240 | if (node == NUMA_NO_NODE) |
3241 | node = set->numa_node; | |
3242 | ||
e155b0c2 JG |
3243 | tags = blk_mq_init_tags(nr_tags, reserved_tags, node, |
3244 | BLK_MQ_FLAG_TO_ALLOC_POLICY(set->flags)); | |
24d2f903 CH |
3245 | if (!tags) |
3246 | return NULL; | |
320ae51f | 3247 | |
590b5b7d | 3248 | tags->rqs = kcalloc_node(nr_tags, sizeof(struct request *), |
36e1f3d1 | 3249 | GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, |
59f082e4 | 3250 | node); |
24d2f903 | 3251 | if (!tags->rqs) { |
e155b0c2 | 3252 | blk_mq_free_tags(tags); |
24d2f903 CH |
3253 | return NULL; |
3254 | } | |
320ae51f | 3255 | |
590b5b7d KC |
3256 | tags->static_rqs = kcalloc_node(nr_tags, sizeof(struct request *), |
3257 | GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, | |
3258 | node); | |
2af8cbe3 JA |
3259 | if (!tags->static_rqs) { |
3260 | kfree(tags->rqs); | |
e155b0c2 | 3261 | blk_mq_free_tags(tags); |
2af8cbe3 JA |
3262 | return NULL; |
3263 | } | |
3264 | ||
cc71a6f4 JA |
3265 | return tags; |
3266 | } | |
3267 | ||
1d9bd516 TH |
3268 | static int blk_mq_init_request(struct blk_mq_tag_set *set, struct request *rq, |
3269 | unsigned int hctx_idx, int node) | |
3270 | { | |
3271 | int ret; | |
3272 | ||
3273 | if (set->ops->init_request) { | |
3274 | ret = set->ops->init_request(set, rq, hctx_idx, node); | |
3275 | if (ret) | |
3276 | return ret; | |
3277 | } | |
3278 | ||
12f5b931 | 3279 | WRITE_ONCE(rq->state, MQ_RQ_IDLE); |
1d9bd516 TH |
3280 | return 0; |
3281 | } | |
3282 | ||
63064be1 JG |
3283 | static int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, |
3284 | struct blk_mq_tags *tags, | |
3285 | unsigned int hctx_idx, unsigned int depth) | |
cc71a6f4 JA |
3286 | { |
3287 | unsigned int i, j, entries_per_page, max_order = 4; | |
4d805131 | 3288 | int node = blk_mq_get_hctx_node(set, hctx_idx); |
cc71a6f4 | 3289 | size_t rq_size, left; |
59f082e4 | 3290 | |
59f082e4 SL |
3291 | if (node == NUMA_NO_NODE) |
3292 | node = set->numa_node; | |
cc71a6f4 JA |
3293 | |
3294 | INIT_LIST_HEAD(&tags->page_list); | |
3295 | ||
320ae51f JA |
3296 | /* |
3297 | * rq_size is the size of the request plus driver payload, rounded | |
3298 | * to the cacheline size | |
3299 | */ | |
24d2f903 | 3300 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 3301 | cache_line_size()); |
cc71a6f4 | 3302 | left = rq_size * depth; |
320ae51f | 3303 | |
cc71a6f4 | 3304 | for (i = 0; i < depth; ) { |
320ae51f JA |
3305 | int this_order = max_order; |
3306 | struct page *page; | |
3307 | int to_do; | |
3308 | void *p; | |
3309 | ||
b3a834b1 | 3310 | while (this_order && left < order_to_size(this_order - 1)) |
320ae51f JA |
3311 | this_order--; |
3312 | ||
3313 | do { | |
59f082e4 | 3314 | page = alloc_pages_node(node, |
36e1f3d1 | 3315 | GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO, |
a5164405 | 3316 | this_order); |
320ae51f JA |
3317 | if (page) |
3318 | break; | |
3319 | if (!this_order--) | |
3320 | break; | |
3321 | if (order_to_size(this_order) < rq_size) | |
3322 | break; | |
3323 | } while (1); | |
3324 | ||
3325 | if (!page) | |
24d2f903 | 3326 | goto fail; |
320ae51f JA |
3327 | |
3328 | page->private = this_order; | |
24d2f903 | 3329 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
3330 | |
3331 | p = page_address(page); | |
f75782e4 CM |
3332 | /* |
3333 | * Allow kmemleak to scan these pages as they contain pointers | |
3334 | * to additional allocations like via ops->init_request(). | |
3335 | */ | |
36e1f3d1 | 3336 | kmemleak_alloc(p, order_to_size(this_order), 1, GFP_NOIO); |
320ae51f | 3337 | entries_per_page = order_to_size(this_order) / rq_size; |
cc71a6f4 | 3338 | to_do = min(entries_per_page, depth - i); |
320ae51f JA |
3339 | left -= to_do * rq_size; |
3340 | for (j = 0; j < to_do; j++) { | |
2af8cbe3 JA |
3341 | struct request *rq = p; |
3342 | ||
3343 | tags->static_rqs[i] = rq; | |
1d9bd516 TH |
3344 | if (blk_mq_init_request(set, rq, hctx_idx, node)) { |
3345 | tags->static_rqs[i] = NULL; | |
3346 | goto fail; | |
e9b267d9 CH |
3347 | } |
3348 | ||
320ae51f JA |
3349 | p += rq_size; |
3350 | i++; | |
3351 | } | |
3352 | } | |
cc71a6f4 | 3353 | return 0; |
320ae51f | 3354 | |
24d2f903 | 3355 | fail: |
cc71a6f4 JA |
3356 | blk_mq_free_rqs(set, tags, hctx_idx); |
3357 | return -ENOMEM; | |
320ae51f JA |
3358 | } |
3359 | ||
bf0beec0 ML |
3360 | struct rq_iter_data { |
3361 | struct blk_mq_hw_ctx *hctx; | |
3362 | bool has_rq; | |
3363 | }; | |
3364 | ||
2dd6532e | 3365 | static bool blk_mq_has_request(struct request *rq, void *data) |
bf0beec0 ML |
3366 | { |
3367 | struct rq_iter_data *iter_data = data; | |
3368 | ||
3369 | if (rq->mq_hctx != iter_data->hctx) | |
3370 | return true; | |
3371 | iter_data->has_rq = true; | |
3372 | return false; | |
3373 | } | |
3374 | ||
3375 | static bool blk_mq_hctx_has_requests(struct blk_mq_hw_ctx *hctx) | |
3376 | { | |
3377 | struct blk_mq_tags *tags = hctx->sched_tags ? | |
3378 | hctx->sched_tags : hctx->tags; | |
3379 | struct rq_iter_data data = { | |
3380 | .hctx = hctx, | |
3381 | }; | |
3382 | ||
3383 | blk_mq_all_tag_iter(tags, blk_mq_has_request, &data); | |
3384 | return data.has_rq; | |
3385 | } | |
3386 | ||
3387 | static inline bool blk_mq_last_cpu_in_hctx(unsigned int cpu, | |
3388 | struct blk_mq_hw_ctx *hctx) | |
3389 | { | |
9b51d9d8 | 3390 | if (cpumask_first_and(hctx->cpumask, cpu_online_mask) != cpu) |
bf0beec0 ML |
3391 | return false; |
3392 | if (cpumask_next_and(cpu, hctx->cpumask, cpu_online_mask) < nr_cpu_ids) | |
3393 | return false; | |
3394 | return true; | |
3395 | } | |
3396 | ||
3397 | static int blk_mq_hctx_notify_offline(unsigned int cpu, struct hlist_node *node) | |
3398 | { | |
3399 | struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node, | |
3400 | struct blk_mq_hw_ctx, cpuhp_online); | |
3401 | ||
3402 | if (!cpumask_test_cpu(cpu, hctx->cpumask) || | |
3403 | !blk_mq_last_cpu_in_hctx(cpu, hctx)) | |
3404 | return 0; | |
3405 | ||
3406 | /* | |
3407 | * Prevent new request from being allocated on the current hctx. | |
3408 | * | |
3409 | * The smp_mb__after_atomic() Pairs with the implied barrier in | |
3410 | * test_and_set_bit_lock in sbitmap_get(). Ensures the inactive flag is | |
3411 | * seen once we return from the tag allocator. | |
3412 | */ | |
3413 | set_bit(BLK_MQ_S_INACTIVE, &hctx->state); | |
3414 | smp_mb__after_atomic(); | |
3415 | ||
3416 | /* | |
3417 | * Try to grab a reference to the queue and wait for any outstanding | |
3418 | * requests. If we could not grab a reference the queue has been | |
3419 | * frozen and there are no requests. | |
3420 | */ | |
3421 | if (percpu_ref_tryget(&hctx->queue->q_usage_counter)) { | |
3422 | while (blk_mq_hctx_has_requests(hctx)) | |
3423 | msleep(5); | |
3424 | percpu_ref_put(&hctx->queue->q_usage_counter); | |
3425 | } | |
3426 | ||
3427 | return 0; | |
3428 | } | |
3429 | ||
3430 | static int blk_mq_hctx_notify_online(unsigned int cpu, struct hlist_node *node) | |
3431 | { | |
3432 | struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node, | |
3433 | struct blk_mq_hw_ctx, cpuhp_online); | |
3434 | ||
3435 | if (cpumask_test_cpu(cpu, hctx->cpumask)) | |
3436 | clear_bit(BLK_MQ_S_INACTIVE, &hctx->state); | |
3437 | return 0; | |
3438 | } | |
3439 | ||
e57690fe JA |
3440 | /* |
3441 | * 'cpu' is going away. splice any existing rq_list entries from this | |
3442 | * software queue to the hw queue dispatch list, and ensure that it | |
3443 | * gets run. | |
3444 | */ | |
9467f859 | 3445 | static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) |
484b4061 | 3446 | { |
9467f859 | 3447 | struct blk_mq_hw_ctx *hctx; |
484b4061 JA |
3448 | struct blk_mq_ctx *ctx; |
3449 | LIST_HEAD(tmp); | |
c16d6b5a | 3450 | enum hctx_type type; |
484b4061 | 3451 | |
9467f859 | 3452 | hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead); |
bf0beec0 ML |
3453 | if (!cpumask_test_cpu(cpu, hctx->cpumask)) |
3454 | return 0; | |
3455 | ||
e57690fe | 3456 | ctx = __blk_mq_get_ctx(hctx->queue, cpu); |
c16d6b5a | 3457 | type = hctx->type; |
484b4061 JA |
3458 | |
3459 | spin_lock(&ctx->lock); | |
c16d6b5a ML |
3460 | if (!list_empty(&ctx->rq_lists[type])) { |
3461 | list_splice_init(&ctx->rq_lists[type], &tmp); | |
484b4061 JA |
3462 | blk_mq_hctx_clear_pending(hctx, ctx); |
3463 | } | |
3464 | spin_unlock(&ctx->lock); | |
3465 | ||
3466 | if (list_empty(&tmp)) | |
9467f859 | 3467 | return 0; |
484b4061 | 3468 | |
e57690fe JA |
3469 | spin_lock(&hctx->lock); |
3470 | list_splice_tail_init(&tmp, &hctx->dispatch); | |
3471 | spin_unlock(&hctx->lock); | |
484b4061 JA |
3472 | |
3473 | blk_mq_run_hw_queue(hctx, true); | |
9467f859 | 3474 | return 0; |
484b4061 JA |
3475 | } |
3476 | ||
9467f859 | 3477 | static void blk_mq_remove_cpuhp(struct blk_mq_hw_ctx *hctx) |
484b4061 | 3478 | { |
bf0beec0 ML |
3479 | if (!(hctx->flags & BLK_MQ_F_STACKING)) |
3480 | cpuhp_state_remove_instance_nocalls(CPUHP_AP_BLK_MQ_ONLINE, | |
3481 | &hctx->cpuhp_online); | |
9467f859 TG |
3482 | cpuhp_state_remove_instance_nocalls(CPUHP_BLK_MQ_DEAD, |
3483 | &hctx->cpuhp_dead); | |
484b4061 JA |
3484 | } |
3485 | ||
364b6181 ML |
3486 | /* |
3487 | * Before freeing hw queue, clearing the flush request reference in | |
3488 | * tags->rqs[] for avoiding potential UAF. | |
3489 | */ | |
3490 | static void blk_mq_clear_flush_rq_mapping(struct blk_mq_tags *tags, | |
3491 | unsigned int queue_depth, struct request *flush_rq) | |
3492 | { | |
3493 | int i; | |
3494 | unsigned long flags; | |
3495 | ||
3496 | /* The hw queue may not be mapped yet */ | |
3497 | if (!tags) | |
3498 | return; | |
3499 | ||
0a467d0f | 3500 | WARN_ON_ONCE(req_ref_read(flush_rq) != 0); |
364b6181 ML |
3501 | |
3502 | for (i = 0; i < queue_depth; i++) | |
3503 | cmpxchg(&tags->rqs[i], flush_rq, NULL); | |
3504 | ||
3505 | /* | |
3506 | * Wait until all pending iteration is done. | |
3507 | * | |
3508 | * Request reference is cleared and it is guaranteed to be observed | |
3509 | * after the ->lock is released. | |
3510 | */ | |
3511 | spin_lock_irqsave(&tags->lock, flags); | |
3512 | spin_unlock_irqrestore(&tags->lock, flags); | |
3513 | } | |
3514 | ||
c3b4afca | 3515 | /* hctx->ctxs will be freed in queue's release handler */ |
08e98fc6 ML |
3516 | static void blk_mq_exit_hctx(struct request_queue *q, |
3517 | struct blk_mq_tag_set *set, | |
3518 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
3519 | { | |
364b6181 ML |
3520 | struct request *flush_rq = hctx->fq->flush_rq; |
3521 | ||
8ab0b7dc ML |
3522 | if (blk_mq_hw_queue_mapped(hctx)) |
3523 | blk_mq_tag_idle(hctx); | |
08e98fc6 | 3524 | |
6cfeadbf ML |
3525 | if (blk_queue_init_done(q)) |
3526 | blk_mq_clear_flush_rq_mapping(set->tags[hctx_idx], | |
3527 | set->queue_depth, flush_rq); | |
f70ced09 | 3528 | if (set->ops->exit_request) |
364b6181 | 3529 | set->ops->exit_request(set, flush_rq, hctx_idx); |
f70ced09 | 3530 | |
08e98fc6 ML |
3531 | if (set->ops->exit_hctx) |
3532 | set->ops->exit_hctx(hctx, hctx_idx); | |
3533 | ||
9467f859 | 3534 | blk_mq_remove_cpuhp(hctx); |
2f8f1336 | 3535 | |
4e5cc99e ML |
3536 | xa_erase(&q->hctx_table, hctx_idx); |
3537 | ||
2f8f1336 ML |
3538 | spin_lock(&q->unused_hctx_lock); |
3539 | list_add(&hctx->hctx_list, &q->unused_hctx_list); | |
3540 | spin_unlock(&q->unused_hctx_lock); | |
08e98fc6 ML |
3541 | } |
3542 | ||
624dbe47 ML |
3543 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
3544 | struct blk_mq_tag_set *set, int nr_queue) | |
3545 | { | |
3546 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 3547 | unsigned long i; |
624dbe47 ML |
3548 | |
3549 | queue_for_each_hw_ctx(q, hctx, i) { | |
3550 | if (i == nr_queue) | |
3551 | break; | |
08e98fc6 | 3552 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 3553 | } |
624dbe47 ML |
3554 | } |
3555 | ||
08e98fc6 ML |
3556 | static int blk_mq_init_hctx(struct request_queue *q, |
3557 | struct blk_mq_tag_set *set, | |
3558 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 3559 | { |
7c6c5b7c ML |
3560 | hctx->queue_num = hctx_idx; |
3561 | ||
bf0beec0 ML |
3562 | if (!(hctx->flags & BLK_MQ_F_STACKING)) |
3563 | cpuhp_state_add_instance_nocalls(CPUHP_AP_BLK_MQ_ONLINE, | |
3564 | &hctx->cpuhp_online); | |
7c6c5b7c ML |
3565 | cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead); |
3566 | ||
3567 | hctx->tags = set->tags[hctx_idx]; | |
3568 | ||
3569 | if (set->ops->init_hctx && | |
3570 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
3571 | goto unregister_cpu_notifier; | |
08e98fc6 | 3572 | |
7c6c5b7c ML |
3573 | if (blk_mq_init_request(set, hctx->fq->flush_rq, hctx_idx, |
3574 | hctx->numa_node)) | |
3575 | goto exit_hctx; | |
4e5cc99e ML |
3576 | |
3577 | if (xa_insert(&q->hctx_table, hctx_idx, hctx, GFP_KERNEL)) | |
3578 | goto exit_flush_rq; | |
3579 | ||
7c6c5b7c ML |
3580 | return 0; |
3581 | ||
4e5cc99e ML |
3582 | exit_flush_rq: |
3583 | if (set->ops->exit_request) | |
3584 | set->ops->exit_request(set, hctx->fq->flush_rq, hctx_idx); | |
7c6c5b7c ML |
3585 | exit_hctx: |
3586 | if (set->ops->exit_hctx) | |
3587 | set->ops->exit_hctx(hctx, hctx_idx); | |
3588 | unregister_cpu_notifier: | |
3589 | blk_mq_remove_cpuhp(hctx); | |
3590 | return -1; | |
3591 | } | |
3592 | ||
3593 | static struct blk_mq_hw_ctx * | |
3594 | blk_mq_alloc_hctx(struct request_queue *q, struct blk_mq_tag_set *set, | |
3595 | int node) | |
3596 | { | |
3597 | struct blk_mq_hw_ctx *hctx; | |
3598 | gfp_t gfp = GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY; | |
3599 | ||
704b914f | 3600 | hctx = kzalloc_node(sizeof(struct blk_mq_hw_ctx), gfp, node); |
7c6c5b7c ML |
3601 | if (!hctx) |
3602 | goto fail_alloc_hctx; | |
3603 | ||
3604 | if (!zalloc_cpumask_var_node(&hctx->cpumask, gfp, node)) | |
3605 | goto free_hctx; | |
3606 | ||
3607 | atomic_set(&hctx->nr_active, 0); | |
08e98fc6 | 3608 | if (node == NUMA_NO_NODE) |
7c6c5b7c ML |
3609 | node = set->numa_node; |
3610 | hctx->numa_node = node; | |
08e98fc6 | 3611 | |
9f993737 | 3612 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); |
08e98fc6 ML |
3613 | spin_lock_init(&hctx->lock); |
3614 | INIT_LIST_HEAD(&hctx->dispatch); | |
3615 | hctx->queue = q; | |
51db1c37 | 3616 | hctx->flags = set->flags & ~BLK_MQ_F_TAG_QUEUE_SHARED; |
08e98fc6 | 3617 | |
2f8f1336 ML |
3618 | INIT_LIST_HEAD(&hctx->hctx_list); |
3619 | ||
320ae51f | 3620 | /* |
08e98fc6 ML |
3621 | * Allocate space for all possible cpus to avoid allocation at |
3622 | * runtime | |
320ae51f | 3623 | */ |
d904bfa7 | 3624 | hctx->ctxs = kmalloc_array_node(nr_cpu_ids, sizeof(void *), |
7c6c5b7c | 3625 | gfp, node); |
08e98fc6 | 3626 | if (!hctx->ctxs) |
7c6c5b7c | 3627 | goto free_cpumask; |
320ae51f | 3628 | |
5b202853 | 3629 | if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8), |
c548e62b | 3630 | gfp, node, false, false)) |
08e98fc6 | 3631 | goto free_ctxs; |
08e98fc6 | 3632 | hctx->nr_ctx = 0; |
320ae51f | 3633 | |
5815839b | 3634 | spin_lock_init(&hctx->dispatch_wait_lock); |
eb619fdb JA |
3635 | init_waitqueue_func_entry(&hctx->dispatch_wait, blk_mq_dispatch_wake); |
3636 | INIT_LIST_HEAD(&hctx->dispatch_wait.entry); | |
3637 | ||
754a1572 | 3638 | hctx->fq = blk_alloc_flush_queue(hctx->numa_node, set->cmd_size, gfp); |
f70ced09 | 3639 | if (!hctx->fq) |
7c6c5b7c | 3640 | goto free_bitmap; |
320ae51f | 3641 | |
7c6c5b7c | 3642 | blk_mq_hctx_kobj_init(hctx); |
6a83e74d | 3643 | |
7c6c5b7c | 3644 | return hctx; |
320ae51f | 3645 | |
08e98fc6 | 3646 | free_bitmap: |
88459642 | 3647 | sbitmap_free(&hctx->ctx_map); |
08e98fc6 ML |
3648 | free_ctxs: |
3649 | kfree(hctx->ctxs); | |
7c6c5b7c ML |
3650 | free_cpumask: |
3651 | free_cpumask_var(hctx->cpumask); | |
3652 | free_hctx: | |
3653 | kfree(hctx); | |
3654 | fail_alloc_hctx: | |
3655 | return NULL; | |
08e98fc6 | 3656 | } |
320ae51f | 3657 | |
320ae51f JA |
3658 | static void blk_mq_init_cpu_queues(struct request_queue *q, |
3659 | unsigned int nr_hw_queues) | |
3660 | { | |
b3c661b1 JA |
3661 | struct blk_mq_tag_set *set = q->tag_set; |
3662 | unsigned int i, j; | |
320ae51f JA |
3663 | |
3664 | for_each_possible_cpu(i) { | |
3665 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
3666 | struct blk_mq_hw_ctx *hctx; | |
c16d6b5a | 3667 | int k; |
320ae51f | 3668 | |
320ae51f JA |
3669 | __ctx->cpu = i; |
3670 | spin_lock_init(&__ctx->lock); | |
c16d6b5a ML |
3671 | for (k = HCTX_TYPE_DEFAULT; k < HCTX_MAX_TYPES; k++) |
3672 | INIT_LIST_HEAD(&__ctx->rq_lists[k]); | |
3673 | ||
320ae51f JA |
3674 | __ctx->queue = q; |
3675 | ||
320ae51f JA |
3676 | /* |
3677 | * Set local node, IFF we have more than one hw queue. If | |
3678 | * not, we remain on the home node of the device | |
3679 | */ | |
b3c661b1 JA |
3680 | for (j = 0; j < set->nr_maps; j++) { |
3681 | hctx = blk_mq_map_queue_type(q, j, i); | |
3682 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
576e85c5 | 3683 | hctx->numa_node = cpu_to_node(i); |
b3c661b1 | 3684 | } |
320ae51f JA |
3685 | } |
3686 | } | |
3687 | ||
63064be1 JG |
3688 | struct blk_mq_tags *blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set, |
3689 | unsigned int hctx_idx, | |
3690 | unsigned int depth) | |
cc71a6f4 | 3691 | { |
63064be1 JG |
3692 | struct blk_mq_tags *tags; |
3693 | int ret; | |
cc71a6f4 | 3694 | |
e155b0c2 | 3695 | tags = blk_mq_alloc_rq_map(set, hctx_idx, depth, set->reserved_tags); |
63064be1 JG |
3696 | if (!tags) |
3697 | return NULL; | |
cc71a6f4 | 3698 | |
63064be1 JG |
3699 | ret = blk_mq_alloc_rqs(set, tags, hctx_idx, depth); |
3700 | if (ret) { | |
e155b0c2 | 3701 | blk_mq_free_rq_map(tags); |
63064be1 JG |
3702 | return NULL; |
3703 | } | |
cc71a6f4 | 3704 | |
63064be1 | 3705 | return tags; |
cc71a6f4 JA |
3706 | } |
3707 | ||
63064be1 JG |
3708 | static bool __blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set, |
3709 | int hctx_idx) | |
cc71a6f4 | 3710 | { |
079a2e3e JG |
3711 | if (blk_mq_is_shared_tags(set->flags)) { |
3712 | set->tags[hctx_idx] = set->shared_tags; | |
1c0706a7 | 3713 | |
e155b0c2 | 3714 | return true; |
bd166ef1 | 3715 | } |
e155b0c2 | 3716 | |
63064be1 JG |
3717 | set->tags[hctx_idx] = blk_mq_alloc_map_and_rqs(set, hctx_idx, |
3718 | set->queue_depth); | |
3719 | ||
3720 | return set->tags[hctx_idx]; | |
cc71a6f4 JA |
3721 | } |
3722 | ||
645db34e JG |
3723 | void blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set, |
3724 | struct blk_mq_tags *tags, | |
3725 | unsigned int hctx_idx) | |
cc71a6f4 | 3726 | { |
645db34e JG |
3727 | if (tags) { |
3728 | blk_mq_free_rqs(set, tags, hctx_idx); | |
e155b0c2 | 3729 | blk_mq_free_rq_map(tags); |
bd166ef1 | 3730 | } |
cc71a6f4 JA |
3731 | } |
3732 | ||
e155b0c2 JG |
3733 | static void __blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set, |
3734 | unsigned int hctx_idx) | |
3735 | { | |
079a2e3e | 3736 | if (!blk_mq_is_shared_tags(set->flags)) |
e155b0c2 JG |
3737 | blk_mq_free_map_and_rqs(set, set->tags[hctx_idx], hctx_idx); |
3738 | ||
3739 | set->tags[hctx_idx] = NULL; | |
cc71a6f4 JA |
3740 | } |
3741 | ||
4b855ad3 | 3742 | static void blk_mq_map_swqueue(struct request_queue *q) |
320ae51f | 3743 | { |
4f481208 ML |
3744 | unsigned int j, hctx_idx; |
3745 | unsigned long i; | |
320ae51f JA |
3746 | struct blk_mq_hw_ctx *hctx; |
3747 | struct blk_mq_ctx *ctx; | |
2a34c087 | 3748 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f JA |
3749 | |
3750 | queue_for_each_hw_ctx(q, hctx, i) { | |
e4043dcf | 3751 | cpumask_clear(hctx->cpumask); |
320ae51f | 3752 | hctx->nr_ctx = 0; |
d416c92c | 3753 | hctx->dispatch_from = NULL; |
320ae51f JA |
3754 | } |
3755 | ||
3756 | /* | |
4b855ad3 | 3757 | * Map software to hardware queues. |
4412efec ML |
3758 | * |
3759 | * If the cpu isn't present, the cpu is mapped to first hctx. | |
320ae51f | 3760 | */ |
20e4d813 | 3761 | for_each_possible_cpu(i) { |
4412efec | 3762 | |
897bb0c7 | 3763 | ctx = per_cpu_ptr(q->queue_ctx, i); |
b3c661b1 | 3764 | for (j = 0; j < set->nr_maps; j++) { |
bb94aea1 JW |
3765 | if (!set->map[j].nr_queues) { |
3766 | ctx->hctxs[j] = blk_mq_map_queue_type(q, | |
3767 | HCTX_TYPE_DEFAULT, i); | |
e5edd5f2 | 3768 | continue; |
bb94aea1 | 3769 | } |
fd689871 ML |
3770 | hctx_idx = set->map[j].mq_map[i]; |
3771 | /* unmapped hw queue can be remapped after CPU topo changed */ | |
3772 | if (!set->tags[hctx_idx] && | |
63064be1 | 3773 | !__blk_mq_alloc_map_and_rqs(set, hctx_idx)) { |
fd689871 ML |
3774 | /* |
3775 | * If tags initialization fail for some hctx, | |
3776 | * that hctx won't be brought online. In this | |
3777 | * case, remap the current ctx to hctx[0] which | |
3778 | * is guaranteed to always have tags allocated | |
3779 | */ | |
3780 | set->map[j].mq_map[i] = 0; | |
3781 | } | |
e5edd5f2 | 3782 | |
b3c661b1 | 3783 | hctx = blk_mq_map_queue_type(q, j, i); |
8ccdf4a3 | 3784 | ctx->hctxs[j] = hctx; |
b3c661b1 JA |
3785 | /* |
3786 | * If the CPU is already set in the mask, then we've | |
3787 | * mapped this one already. This can happen if | |
3788 | * devices share queues across queue maps. | |
3789 | */ | |
3790 | if (cpumask_test_cpu(i, hctx->cpumask)) | |
3791 | continue; | |
3792 | ||
3793 | cpumask_set_cpu(i, hctx->cpumask); | |
3794 | hctx->type = j; | |
3795 | ctx->index_hw[hctx->type] = hctx->nr_ctx; | |
3796 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
3797 | ||
3798 | /* | |
3799 | * If the nr_ctx type overflows, we have exceeded the | |
3800 | * amount of sw queues we can support. | |
3801 | */ | |
3802 | BUG_ON(!hctx->nr_ctx); | |
3803 | } | |
bb94aea1 JW |
3804 | |
3805 | for (; j < HCTX_MAX_TYPES; j++) | |
3806 | ctx->hctxs[j] = blk_mq_map_queue_type(q, | |
3807 | HCTX_TYPE_DEFAULT, i); | |
320ae51f | 3808 | } |
506e931f JA |
3809 | |
3810 | queue_for_each_hw_ctx(q, hctx, i) { | |
4412efec ML |
3811 | /* |
3812 | * If no software queues are mapped to this hardware queue, | |
3813 | * disable it and free the request entries. | |
3814 | */ | |
3815 | if (!hctx->nr_ctx) { | |
3816 | /* Never unmap queue 0. We need it as a | |
3817 | * fallback in case of a new remap fails | |
3818 | * allocation | |
3819 | */ | |
e155b0c2 JG |
3820 | if (i) |
3821 | __blk_mq_free_map_and_rqs(set, i); | |
4412efec ML |
3822 | |
3823 | hctx->tags = NULL; | |
3824 | continue; | |
3825 | } | |
484b4061 | 3826 | |
2a34c087 ML |
3827 | hctx->tags = set->tags[i]; |
3828 | WARN_ON(!hctx->tags); | |
3829 | ||
889fa31f CY |
3830 | /* |
3831 | * Set the map size to the number of mapped software queues. | |
3832 | * This is more accurate and more efficient than looping | |
3833 | * over all possibly mapped software queues. | |
3834 | */ | |
88459642 | 3835 | sbitmap_resize(&hctx->ctx_map, hctx->nr_ctx); |
889fa31f | 3836 | |
484b4061 JA |
3837 | /* |
3838 | * Initialize batch roundrobin counts | |
3839 | */ | |
f82ddf19 | 3840 | hctx->next_cpu = blk_mq_first_mapped_cpu(hctx); |
506e931f JA |
3841 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; |
3842 | } | |
320ae51f JA |
3843 | } |
3844 | ||
8e8320c9 JA |
3845 | /* |
3846 | * Caller needs to ensure that we're either frozen/quiesced, or that | |
3847 | * the queue isn't live yet. | |
3848 | */ | |
2404e607 | 3849 | static void queue_set_hctx_shared(struct request_queue *q, bool shared) |
0d2602ca JA |
3850 | { |
3851 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 3852 | unsigned long i; |
0d2602ca | 3853 | |
2404e607 | 3854 | queue_for_each_hw_ctx(q, hctx, i) { |
454bb677 | 3855 | if (shared) { |
51db1c37 | 3856 | hctx->flags |= BLK_MQ_F_TAG_QUEUE_SHARED; |
454bb677 YK |
3857 | } else { |
3858 | blk_mq_tag_idle(hctx); | |
51db1c37 | 3859 | hctx->flags &= ~BLK_MQ_F_TAG_QUEUE_SHARED; |
454bb677 | 3860 | } |
2404e607 JM |
3861 | } |
3862 | } | |
3863 | ||
655ac300 HR |
3864 | static void blk_mq_update_tag_set_shared(struct blk_mq_tag_set *set, |
3865 | bool shared) | |
2404e607 JM |
3866 | { |
3867 | struct request_queue *q; | |
0d2602ca | 3868 | |
705cda97 BVA |
3869 | lockdep_assert_held(&set->tag_list_lock); |
3870 | ||
0d2602ca JA |
3871 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
3872 | blk_mq_freeze_queue(q); | |
2404e607 | 3873 | queue_set_hctx_shared(q, shared); |
0d2602ca JA |
3874 | blk_mq_unfreeze_queue(q); |
3875 | } | |
3876 | } | |
3877 | ||
3878 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
3879 | { | |
3880 | struct blk_mq_tag_set *set = q->tag_set; | |
3881 | ||
0d2602ca | 3882 | mutex_lock(&set->tag_list_lock); |
08c875cb | 3883 | list_del(&q->tag_set_list); |
2404e607 JM |
3884 | if (list_is_singular(&set->tag_list)) { |
3885 | /* just transitioned to unshared */ | |
51db1c37 | 3886 | set->flags &= ~BLK_MQ_F_TAG_QUEUE_SHARED; |
2404e607 | 3887 | /* update existing queue */ |
655ac300 | 3888 | blk_mq_update_tag_set_shared(set, false); |
2404e607 | 3889 | } |
0d2602ca | 3890 | mutex_unlock(&set->tag_list_lock); |
a347c7ad | 3891 | INIT_LIST_HEAD(&q->tag_set_list); |
0d2602ca JA |
3892 | } |
3893 | ||
3894 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
3895 | struct request_queue *q) | |
3896 | { | |
0d2602ca | 3897 | mutex_lock(&set->tag_list_lock); |
2404e607 | 3898 | |
ff821d27 JA |
3899 | /* |
3900 | * Check to see if we're transitioning to shared (from 1 to 2 queues). | |
3901 | */ | |
3902 | if (!list_empty(&set->tag_list) && | |
51db1c37 ML |
3903 | !(set->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) { |
3904 | set->flags |= BLK_MQ_F_TAG_QUEUE_SHARED; | |
2404e607 | 3905 | /* update existing queue */ |
655ac300 | 3906 | blk_mq_update_tag_set_shared(set, true); |
2404e607 | 3907 | } |
51db1c37 | 3908 | if (set->flags & BLK_MQ_F_TAG_QUEUE_SHARED) |
2404e607 | 3909 | queue_set_hctx_shared(q, true); |
08c875cb | 3910 | list_add_tail(&q->tag_set_list, &set->tag_list); |
2404e607 | 3911 | |
0d2602ca JA |
3912 | mutex_unlock(&set->tag_list_lock); |
3913 | } | |
3914 | ||
1db4909e ML |
3915 | /* All allocations will be freed in release handler of q->mq_kobj */ |
3916 | static int blk_mq_alloc_ctxs(struct request_queue *q) | |
3917 | { | |
3918 | struct blk_mq_ctxs *ctxs; | |
3919 | int cpu; | |
3920 | ||
3921 | ctxs = kzalloc(sizeof(*ctxs), GFP_KERNEL); | |
3922 | if (!ctxs) | |
3923 | return -ENOMEM; | |
3924 | ||
3925 | ctxs->queue_ctx = alloc_percpu(struct blk_mq_ctx); | |
3926 | if (!ctxs->queue_ctx) | |
3927 | goto fail; | |
3928 | ||
3929 | for_each_possible_cpu(cpu) { | |
3930 | struct blk_mq_ctx *ctx = per_cpu_ptr(ctxs->queue_ctx, cpu); | |
3931 | ctx->ctxs = ctxs; | |
3932 | } | |
3933 | ||
3934 | q->mq_kobj = &ctxs->kobj; | |
3935 | q->queue_ctx = ctxs->queue_ctx; | |
3936 | ||
3937 | return 0; | |
3938 | fail: | |
3939 | kfree(ctxs); | |
3940 | return -ENOMEM; | |
3941 | } | |
3942 | ||
e09aae7e ML |
3943 | /* |
3944 | * It is the actual release handler for mq, but we do it from | |
3945 | * request queue's release handler for avoiding use-after-free | |
3946 | * and headache because q->mq_kobj shouldn't have been introduced, | |
3947 | * but we can't group ctx/kctx kobj without it. | |
3948 | */ | |
3949 | void blk_mq_release(struct request_queue *q) | |
3950 | { | |
2f8f1336 | 3951 | struct blk_mq_hw_ctx *hctx, *next; |
4f481208 | 3952 | unsigned long i; |
e09aae7e | 3953 | |
2f8f1336 ML |
3954 | queue_for_each_hw_ctx(q, hctx, i) |
3955 | WARN_ON_ONCE(hctx && list_empty(&hctx->hctx_list)); | |
3956 | ||
3957 | /* all hctx are in .unused_hctx_list now */ | |
3958 | list_for_each_entry_safe(hctx, next, &q->unused_hctx_list, hctx_list) { | |
3959 | list_del_init(&hctx->hctx_list); | |
6c8b232e | 3960 | kobject_put(&hctx->kobj); |
c3b4afca | 3961 | } |
e09aae7e | 3962 | |
4e5cc99e | 3963 | xa_destroy(&q->hctx_table); |
e09aae7e | 3964 | |
7ea5fe31 ML |
3965 | /* |
3966 | * release .mq_kobj and sw queue's kobject now because | |
3967 | * both share lifetime with request queue. | |
3968 | */ | |
3969 | blk_mq_sysfs_deinit(q); | |
e09aae7e ML |
3970 | } |
3971 | ||
5ec780a6 | 3972 | static struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set, |
2f227bb9 | 3973 | void *queuedata) |
b62c21b7 | 3974 | { |
26a9750a CH |
3975 | struct request_queue *q; |
3976 | int ret; | |
b62c21b7 | 3977 | |
704b914f | 3978 | q = blk_alloc_queue(set->numa_node, set->flags & BLK_MQ_F_BLOCKING); |
26a9750a | 3979 | if (!q) |
b62c21b7 | 3980 | return ERR_PTR(-ENOMEM); |
26a9750a CH |
3981 | q->queuedata = queuedata; |
3982 | ret = blk_mq_init_allocated_queue(set, q); | |
3983 | if (ret) { | |
6f8191fd | 3984 | blk_put_queue(q); |
26a9750a CH |
3985 | return ERR_PTR(ret); |
3986 | } | |
b62c21b7 MS |
3987 | return q; |
3988 | } | |
2f227bb9 CH |
3989 | |
3990 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) | |
3991 | { | |
3992 | return blk_mq_init_queue_data(set, NULL); | |
3993 | } | |
b62c21b7 MS |
3994 | EXPORT_SYMBOL(blk_mq_init_queue); |
3995 | ||
6f8191fd CH |
3996 | /** |
3997 | * blk_mq_destroy_queue - shutdown a request queue | |
3998 | * @q: request queue to shutdown | |
3999 | * | |
4000 | * This shuts down a request queue allocated by blk_mq_init_queue() and drops | |
4001 | * the initial reference. All future requests will failed with -ENODEV. | |
4002 | * | |
4003 | * Context: can sleep | |
4004 | */ | |
4005 | void blk_mq_destroy_queue(struct request_queue *q) | |
4006 | { | |
4007 | WARN_ON_ONCE(!queue_is_mq(q)); | |
4008 | WARN_ON_ONCE(blk_queue_registered(q)); | |
4009 | ||
4010 | might_sleep(); | |
4011 | ||
4012 | blk_queue_flag_set(QUEUE_FLAG_DYING, q); | |
4013 | blk_queue_start_drain(q); | |
4014 | blk_freeze_queue(q); | |
4015 | ||
4016 | blk_sync_queue(q); | |
4017 | blk_mq_cancel_work_sync(q); | |
4018 | blk_mq_exit_queue(q); | |
4019 | ||
4020 | /* @q is and will stay empty, shutdown and put */ | |
4021 | blk_put_queue(q); | |
4022 | } | |
4023 | EXPORT_SYMBOL(blk_mq_destroy_queue); | |
4024 | ||
4dcc4874 CH |
4025 | struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata, |
4026 | struct lock_class_key *lkclass) | |
9316a9ed JA |
4027 | { |
4028 | struct request_queue *q; | |
b461dfc4 | 4029 | struct gendisk *disk; |
9316a9ed | 4030 | |
b461dfc4 CH |
4031 | q = blk_mq_init_queue_data(set, queuedata); |
4032 | if (IS_ERR(q)) | |
4033 | return ERR_CAST(q); | |
9316a9ed | 4034 | |
4a1fa41d | 4035 | disk = __alloc_disk_node(q, set->numa_node, lkclass); |
b461dfc4 | 4036 | if (!disk) { |
0a3e5cc7 | 4037 | blk_mq_destroy_queue(q); |
b461dfc4 | 4038 | return ERR_PTR(-ENOMEM); |
9316a9ed | 4039 | } |
6f8191fd | 4040 | set_bit(GD_OWNS_QUEUE, &disk->state); |
b461dfc4 | 4041 | return disk; |
9316a9ed | 4042 | } |
b461dfc4 | 4043 | EXPORT_SYMBOL(__blk_mq_alloc_disk); |
9316a9ed | 4044 | |
6f8191fd CH |
4045 | struct gendisk *blk_mq_alloc_disk_for_queue(struct request_queue *q, |
4046 | struct lock_class_key *lkclass) | |
4047 | { | |
4048 | if (!blk_get_queue(q)) | |
4049 | return NULL; | |
4050 | return __alloc_disk_node(q, NUMA_NO_NODE, lkclass); | |
4051 | } | |
4052 | EXPORT_SYMBOL(blk_mq_alloc_disk_for_queue); | |
4053 | ||
34d11ffa JW |
4054 | static struct blk_mq_hw_ctx *blk_mq_alloc_and_init_hctx( |
4055 | struct blk_mq_tag_set *set, struct request_queue *q, | |
4056 | int hctx_idx, int node) | |
4057 | { | |
2f8f1336 | 4058 | struct blk_mq_hw_ctx *hctx = NULL, *tmp; |
34d11ffa | 4059 | |
2f8f1336 ML |
4060 | /* reuse dead hctx first */ |
4061 | spin_lock(&q->unused_hctx_lock); | |
4062 | list_for_each_entry(tmp, &q->unused_hctx_list, hctx_list) { | |
4063 | if (tmp->numa_node == node) { | |
4064 | hctx = tmp; | |
4065 | break; | |
4066 | } | |
4067 | } | |
4068 | if (hctx) | |
4069 | list_del_init(&hctx->hctx_list); | |
4070 | spin_unlock(&q->unused_hctx_lock); | |
4071 | ||
4072 | if (!hctx) | |
4073 | hctx = blk_mq_alloc_hctx(q, set, node); | |
34d11ffa | 4074 | if (!hctx) |
7c6c5b7c | 4075 | goto fail; |
34d11ffa | 4076 | |
7c6c5b7c ML |
4077 | if (blk_mq_init_hctx(q, set, hctx, hctx_idx)) |
4078 | goto free_hctx; | |
34d11ffa JW |
4079 | |
4080 | return hctx; | |
7c6c5b7c ML |
4081 | |
4082 | free_hctx: | |
4083 | kobject_put(&hctx->kobj); | |
4084 | fail: | |
4085 | return NULL; | |
34d11ffa JW |
4086 | } |
4087 | ||
868f2f0b KB |
4088 | static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, |
4089 | struct request_queue *q) | |
320ae51f | 4090 | { |
4e5cc99e ML |
4091 | struct blk_mq_hw_ctx *hctx; |
4092 | unsigned long i, j; | |
ac0d6b92 | 4093 | |
fb350e0a ML |
4094 | /* protect against switching io scheduler */ |
4095 | mutex_lock(&q->sysfs_lock); | |
24d2f903 | 4096 | for (i = 0; i < set->nr_hw_queues; i++) { |
306f13ee | 4097 | int old_node; |
4d805131 | 4098 | int node = blk_mq_get_hctx_node(set, i); |
4e5cc99e | 4099 | struct blk_mq_hw_ctx *old_hctx = xa_load(&q->hctx_table, i); |
868f2f0b | 4100 | |
306f13ee ML |
4101 | if (old_hctx) { |
4102 | old_node = old_hctx->numa_node; | |
4103 | blk_mq_exit_hctx(q, set, old_hctx, i); | |
4104 | } | |
868f2f0b | 4105 | |
4e5cc99e | 4106 | if (!blk_mq_alloc_and_init_hctx(set, q, i, node)) { |
306f13ee | 4107 | if (!old_hctx) |
34d11ffa | 4108 | break; |
306f13ee ML |
4109 | pr_warn("Allocate new hctx on node %d fails, fallback to previous one on node %d\n", |
4110 | node, old_node); | |
4e5cc99e ML |
4111 | hctx = blk_mq_alloc_and_init_hctx(set, q, i, old_node); |
4112 | WARN_ON_ONCE(!hctx); | |
868f2f0b | 4113 | } |
320ae51f | 4114 | } |
e01ad46d JW |
4115 | /* |
4116 | * Increasing nr_hw_queues fails. Free the newly allocated | |
4117 | * hctxs and keep the previous q->nr_hw_queues. | |
4118 | */ | |
4119 | if (i != set->nr_hw_queues) { | |
4120 | j = q->nr_hw_queues; | |
e01ad46d JW |
4121 | } else { |
4122 | j = i; | |
e01ad46d JW |
4123 | q->nr_hw_queues = set->nr_hw_queues; |
4124 | } | |
34d11ffa | 4125 | |
4e5cc99e ML |
4126 | xa_for_each_start(&q->hctx_table, j, hctx, j) |
4127 | blk_mq_exit_hctx(q, set, hctx, j); | |
fb350e0a | 4128 | mutex_unlock(&q->sysfs_lock); |
868f2f0b KB |
4129 | } |
4130 | ||
42ee3061 ML |
4131 | static void blk_mq_update_poll_flag(struct request_queue *q) |
4132 | { | |
4133 | struct blk_mq_tag_set *set = q->tag_set; | |
4134 | ||
4135 | if (set->nr_maps > HCTX_TYPE_POLL && | |
4136 | set->map[HCTX_TYPE_POLL].nr_queues) | |
4137 | blk_queue_flag_set(QUEUE_FLAG_POLL, q); | |
4138 | else | |
4139 | blk_queue_flag_clear(QUEUE_FLAG_POLL, q); | |
4140 | } | |
4141 | ||
26a9750a CH |
4142 | int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, |
4143 | struct request_queue *q) | |
868f2f0b | 4144 | { |
704b914f ML |
4145 | WARN_ON_ONCE(blk_queue_has_srcu(q) != |
4146 | !!(set->flags & BLK_MQ_F_BLOCKING)); | |
4147 | ||
66841672 ML |
4148 | /* mark the queue as mq asap */ |
4149 | q->mq_ops = set->ops; | |
4150 | ||
34dbad5d | 4151 | q->poll_cb = blk_stat_alloc_callback(blk_mq_poll_stats_fn, |
720b8ccc SB |
4152 | blk_mq_poll_stats_bkt, |
4153 | BLK_MQ_POLL_STATS_BKTS, q); | |
34dbad5d OS |
4154 | if (!q->poll_cb) |
4155 | goto err_exit; | |
4156 | ||
1db4909e | 4157 | if (blk_mq_alloc_ctxs(q)) |
41de54c6 | 4158 | goto err_poll; |
868f2f0b | 4159 | |
737f98cf ML |
4160 | /* init q->mq_kobj and sw queues' kobjects */ |
4161 | blk_mq_sysfs_init(q); | |
4162 | ||
2f8f1336 ML |
4163 | INIT_LIST_HEAD(&q->unused_hctx_list); |
4164 | spin_lock_init(&q->unused_hctx_lock); | |
4165 | ||
4e5cc99e ML |
4166 | xa_init(&q->hctx_table); |
4167 | ||
868f2f0b KB |
4168 | blk_mq_realloc_hw_ctxs(set, q); |
4169 | if (!q->nr_hw_queues) | |
4170 | goto err_hctxs; | |
320ae51f | 4171 | |
287922eb | 4172 | INIT_WORK(&q->timeout_work, blk_mq_timeout_work); |
e56f698b | 4173 | blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); |
320ae51f | 4174 | |
a8908939 | 4175 | q->tag_set = set; |
320ae51f | 4176 | |
94eddfbe | 4177 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
42ee3061 | 4178 | blk_mq_update_poll_flag(q); |
320ae51f | 4179 | |
2849450a | 4180 | INIT_DELAYED_WORK(&q->requeue_work, blk_mq_requeue_work); |
6fca6a61 CH |
4181 | INIT_LIST_HEAD(&q->requeue_list); |
4182 | spin_lock_init(&q->requeue_lock); | |
4183 | ||
eba71768 JA |
4184 | q->nr_requests = set->queue_depth; |
4185 | ||
64f1c21e JA |
4186 | /* |
4187 | * Default to classic polling | |
4188 | */ | |
29ece8b4 | 4189 | q->poll_nsec = BLK_MQ_POLL_CLASSIC; |
64f1c21e | 4190 | |
24d2f903 | 4191 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
0d2602ca | 4192 | blk_mq_add_queue_tag_set(set, q); |
4b855ad3 | 4193 | blk_mq_map_swqueue(q); |
26a9750a | 4194 | return 0; |
18741986 | 4195 | |
320ae51f | 4196 | err_hctxs: |
943f45b9 | 4197 | blk_mq_release(q); |
41de54c6 JS |
4198 | err_poll: |
4199 | blk_stat_free_callback(q->poll_cb); | |
4200 | q->poll_cb = NULL; | |
c7de5726 ML |
4201 | err_exit: |
4202 | q->mq_ops = NULL; | |
26a9750a | 4203 | return -ENOMEM; |
320ae51f | 4204 | } |
b62c21b7 | 4205 | EXPORT_SYMBOL(blk_mq_init_allocated_queue); |
320ae51f | 4206 | |
c7e2d94b ML |
4207 | /* tags can _not_ be used after returning from blk_mq_exit_queue */ |
4208 | void blk_mq_exit_queue(struct request_queue *q) | |
320ae51f | 4209 | { |
630ef623 | 4210 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 4211 | |
630ef623 | 4212 | /* Checks hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED. */ |
624dbe47 | 4213 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
630ef623 BVA |
4214 | /* May clear BLK_MQ_F_TAG_QUEUE_SHARED in hctx->flags. */ |
4215 | blk_mq_del_queue_tag_set(q); | |
320ae51f | 4216 | } |
320ae51f | 4217 | |
a5164405 JA |
4218 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
4219 | { | |
4220 | int i; | |
4221 | ||
079a2e3e JG |
4222 | if (blk_mq_is_shared_tags(set->flags)) { |
4223 | set->shared_tags = blk_mq_alloc_map_and_rqs(set, | |
e155b0c2 JG |
4224 | BLK_MQ_NO_HCTX_IDX, |
4225 | set->queue_depth); | |
079a2e3e | 4226 | if (!set->shared_tags) |
e155b0c2 JG |
4227 | return -ENOMEM; |
4228 | } | |
4229 | ||
8229cca8 | 4230 | for (i = 0; i < set->nr_hw_queues; i++) { |
63064be1 | 4231 | if (!__blk_mq_alloc_map_and_rqs(set, i)) |
a5164405 | 4232 | goto out_unwind; |
8229cca8 XT |
4233 | cond_resched(); |
4234 | } | |
a5164405 JA |
4235 | |
4236 | return 0; | |
4237 | ||
4238 | out_unwind: | |
4239 | while (--i >= 0) | |
e155b0c2 JG |
4240 | __blk_mq_free_map_and_rqs(set, i); |
4241 | ||
079a2e3e JG |
4242 | if (blk_mq_is_shared_tags(set->flags)) { |
4243 | blk_mq_free_map_and_rqs(set, set->shared_tags, | |
e155b0c2 | 4244 | BLK_MQ_NO_HCTX_IDX); |
645db34e | 4245 | } |
a5164405 | 4246 | |
a5164405 JA |
4247 | return -ENOMEM; |
4248 | } | |
4249 | ||
4250 | /* | |
4251 | * Allocate the request maps associated with this tag_set. Note that this | |
4252 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
4253 | * will be updated to reflect the allocated depth. | |
4254 | */ | |
63064be1 | 4255 | static int blk_mq_alloc_set_map_and_rqs(struct blk_mq_tag_set *set) |
a5164405 JA |
4256 | { |
4257 | unsigned int depth; | |
4258 | int err; | |
4259 | ||
4260 | depth = set->queue_depth; | |
4261 | do { | |
4262 | err = __blk_mq_alloc_rq_maps(set); | |
4263 | if (!err) | |
4264 | break; | |
4265 | ||
4266 | set->queue_depth >>= 1; | |
4267 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
4268 | err = -ENOMEM; | |
4269 | break; | |
4270 | } | |
4271 | } while (set->queue_depth); | |
4272 | ||
4273 | if (!set->queue_depth || err) { | |
4274 | pr_err("blk-mq: failed to allocate request map\n"); | |
4275 | return -ENOMEM; | |
4276 | } | |
4277 | ||
4278 | if (depth != set->queue_depth) | |
4279 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
4280 | depth, set->queue_depth); | |
4281 | ||
4282 | return 0; | |
4283 | } | |
4284 | ||
a4e1d0b7 | 4285 | static void blk_mq_update_queue_map(struct blk_mq_tag_set *set) |
ebe8bddb | 4286 | { |
6e66b493 BVA |
4287 | /* |
4288 | * blk_mq_map_queues() and multiple .map_queues() implementations | |
4289 | * expect that set->map[HCTX_TYPE_DEFAULT].nr_queues is set to the | |
4290 | * number of hardware queues. | |
4291 | */ | |
4292 | if (set->nr_maps == 1) | |
4293 | set->map[HCTX_TYPE_DEFAULT].nr_queues = set->nr_hw_queues; | |
4294 | ||
59388702 | 4295 | if (set->ops->map_queues && !is_kdump_kernel()) { |
b3c661b1 JA |
4296 | int i; |
4297 | ||
7d4901a9 ML |
4298 | /* |
4299 | * transport .map_queues is usually done in the following | |
4300 | * way: | |
4301 | * | |
4302 | * for (queue = 0; queue < set->nr_hw_queues; queue++) { | |
4303 | * mask = get_cpu_mask(queue) | |
4304 | * for_each_cpu(cpu, mask) | |
b3c661b1 | 4305 | * set->map[x].mq_map[cpu] = queue; |
7d4901a9 ML |
4306 | * } |
4307 | * | |
4308 | * When we need to remap, the table has to be cleared for | |
4309 | * killing stale mapping since one CPU may not be mapped | |
4310 | * to any hw queue. | |
4311 | */ | |
b3c661b1 JA |
4312 | for (i = 0; i < set->nr_maps; i++) |
4313 | blk_mq_clear_mq_map(&set->map[i]); | |
7d4901a9 | 4314 | |
a4e1d0b7 | 4315 | set->ops->map_queues(set); |
b3c661b1 JA |
4316 | } else { |
4317 | BUG_ON(set->nr_maps > 1); | |
a4e1d0b7 | 4318 | blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]); |
b3c661b1 | 4319 | } |
ebe8bddb OS |
4320 | } |
4321 | ||
f7e76dbc BVA |
4322 | static int blk_mq_realloc_tag_set_tags(struct blk_mq_tag_set *set, |
4323 | int cur_nr_hw_queues, int new_nr_hw_queues) | |
4324 | { | |
4325 | struct blk_mq_tags **new_tags; | |
4326 | ||
4327 | if (cur_nr_hw_queues >= new_nr_hw_queues) | |
4328 | return 0; | |
4329 | ||
4330 | new_tags = kcalloc_node(new_nr_hw_queues, sizeof(struct blk_mq_tags *), | |
4331 | GFP_KERNEL, set->numa_node); | |
4332 | if (!new_tags) | |
4333 | return -ENOMEM; | |
4334 | ||
4335 | if (set->tags) | |
4336 | memcpy(new_tags, set->tags, cur_nr_hw_queues * | |
4337 | sizeof(*set->tags)); | |
4338 | kfree(set->tags); | |
4339 | set->tags = new_tags; | |
4340 | set->nr_hw_queues = new_nr_hw_queues; | |
4341 | ||
4342 | return 0; | |
4343 | } | |
4344 | ||
91cdf265 MI |
4345 | static int blk_mq_alloc_tag_set_tags(struct blk_mq_tag_set *set, |
4346 | int new_nr_hw_queues) | |
4347 | { | |
4348 | return blk_mq_realloc_tag_set_tags(set, 0, new_nr_hw_queues); | |
4349 | } | |
4350 | ||
a4391c64 JA |
4351 | /* |
4352 | * Alloc a tag set to be associated with one or more request queues. | |
4353 | * May fail with EINVAL for various error conditions. May adjust the | |
c018c84f | 4354 | * requested depth down, if it's too large. In that case, the set |
a4391c64 JA |
4355 | * value will be stored in set->queue_depth. |
4356 | */ | |
24d2f903 CH |
4357 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
4358 | { | |
b3c661b1 | 4359 | int i, ret; |
da695ba2 | 4360 | |
205fb5f5 BVA |
4361 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
4362 | ||
24d2f903 CH |
4363 | if (!set->nr_hw_queues) |
4364 | return -EINVAL; | |
a4391c64 | 4365 | if (!set->queue_depth) |
24d2f903 CH |
4366 | return -EINVAL; |
4367 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
4368 | return -EINVAL; | |
4369 | ||
7d7e0f90 | 4370 | if (!set->ops->queue_rq) |
24d2f903 CH |
4371 | return -EINVAL; |
4372 | ||
de148297 ML |
4373 | if (!set->ops->get_budget ^ !set->ops->put_budget) |
4374 | return -EINVAL; | |
4375 | ||
a4391c64 JA |
4376 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
4377 | pr_info("blk-mq: reduced tag depth to %u\n", | |
4378 | BLK_MQ_MAX_DEPTH); | |
4379 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
4380 | } | |
24d2f903 | 4381 | |
b3c661b1 JA |
4382 | if (!set->nr_maps) |
4383 | set->nr_maps = 1; | |
4384 | else if (set->nr_maps > HCTX_MAX_TYPES) | |
4385 | return -EINVAL; | |
4386 | ||
6637fadf SL |
4387 | /* |
4388 | * If a crashdump is active, then we are potentially in a very | |
4389 | * memory constrained environment. Limit us to 1 queue and | |
4390 | * 64 tags to prevent using too much memory. | |
4391 | */ | |
4392 | if (is_kdump_kernel()) { | |
4393 | set->nr_hw_queues = 1; | |
59388702 | 4394 | set->nr_maps = 1; |
6637fadf SL |
4395 | set->queue_depth = min(64U, set->queue_depth); |
4396 | } | |
868f2f0b | 4397 | /* |
392546ae JA |
4398 | * There is no use for more h/w queues than cpus if we just have |
4399 | * a single map | |
868f2f0b | 4400 | */ |
392546ae | 4401 | if (set->nr_maps == 1 && set->nr_hw_queues > nr_cpu_ids) |
868f2f0b | 4402 | set->nr_hw_queues = nr_cpu_ids; |
6637fadf | 4403 | |
91cdf265 | 4404 | if (blk_mq_alloc_tag_set_tags(set, set->nr_hw_queues) < 0) |
a5164405 | 4405 | return -ENOMEM; |
24d2f903 | 4406 | |
da695ba2 | 4407 | ret = -ENOMEM; |
b3c661b1 JA |
4408 | for (i = 0; i < set->nr_maps; i++) { |
4409 | set->map[i].mq_map = kcalloc_node(nr_cpu_ids, | |
07b35eb5 | 4410 | sizeof(set->map[i].mq_map[0]), |
b3c661b1 JA |
4411 | GFP_KERNEL, set->numa_node); |
4412 | if (!set->map[i].mq_map) | |
4413 | goto out_free_mq_map; | |
59388702 | 4414 | set->map[i].nr_queues = is_kdump_kernel() ? 1 : set->nr_hw_queues; |
b3c661b1 | 4415 | } |
bdd17e75 | 4416 | |
a4e1d0b7 | 4417 | blk_mq_update_queue_map(set); |
da695ba2 | 4418 | |
63064be1 | 4419 | ret = blk_mq_alloc_set_map_and_rqs(set); |
da695ba2 | 4420 | if (ret) |
bdd17e75 | 4421 | goto out_free_mq_map; |
24d2f903 | 4422 | |
0d2602ca JA |
4423 | mutex_init(&set->tag_list_lock); |
4424 | INIT_LIST_HEAD(&set->tag_list); | |
4425 | ||
24d2f903 | 4426 | return 0; |
bdd17e75 CH |
4427 | |
4428 | out_free_mq_map: | |
b3c661b1 JA |
4429 | for (i = 0; i < set->nr_maps; i++) { |
4430 | kfree(set->map[i].mq_map); | |
4431 | set->map[i].mq_map = NULL; | |
4432 | } | |
5676e7b6 RE |
4433 | kfree(set->tags); |
4434 | set->tags = NULL; | |
da695ba2 | 4435 | return ret; |
24d2f903 CH |
4436 | } |
4437 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
4438 | ||
cdb14e0f CH |
4439 | /* allocate and initialize a tagset for a simple single-queue device */ |
4440 | int blk_mq_alloc_sq_tag_set(struct blk_mq_tag_set *set, | |
4441 | const struct blk_mq_ops *ops, unsigned int queue_depth, | |
4442 | unsigned int set_flags) | |
4443 | { | |
4444 | memset(set, 0, sizeof(*set)); | |
4445 | set->ops = ops; | |
4446 | set->nr_hw_queues = 1; | |
4447 | set->nr_maps = 1; | |
4448 | set->queue_depth = queue_depth; | |
4449 | set->numa_node = NUMA_NO_NODE; | |
4450 | set->flags = set_flags; | |
4451 | return blk_mq_alloc_tag_set(set); | |
4452 | } | |
4453 | EXPORT_SYMBOL_GPL(blk_mq_alloc_sq_tag_set); | |
4454 | ||
24d2f903 CH |
4455 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) |
4456 | { | |
b3c661b1 | 4457 | int i, j; |
24d2f903 | 4458 | |
f7e76dbc | 4459 | for (i = 0; i < set->nr_hw_queues; i++) |
e155b0c2 | 4460 | __blk_mq_free_map_and_rqs(set, i); |
484b4061 | 4461 | |
079a2e3e JG |
4462 | if (blk_mq_is_shared_tags(set->flags)) { |
4463 | blk_mq_free_map_and_rqs(set, set->shared_tags, | |
e155b0c2 JG |
4464 | BLK_MQ_NO_HCTX_IDX); |
4465 | } | |
32bc15af | 4466 | |
b3c661b1 JA |
4467 | for (j = 0; j < set->nr_maps; j++) { |
4468 | kfree(set->map[j].mq_map); | |
4469 | set->map[j].mq_map = NULL; | |
4470 | } | |
bdd17e75 | 4471 | |
981bd189 | 4472 | kfree(set->tags); |
5676e7b6 | 4473 | set->tags = NULL; |
24d2f903 CH |
4474 | } |
4475 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
4476 | ||
e3a2b3f9 JA |
4477 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
4478 | { | |
4479 | struct blk_mq_tag_set *set = q->tag_set; | |
4480 | struct blk_mq_hw_ctx *hctx; | |
4f481208 ML |
4481 | int ret; |
4482 | unsigned long i; | |
e3a2b3f9 | 4483 | |
bd166ef1 | 4484 | if (!set) |
e3a2b3f9 JA |
4485 | return -EINVAL; |
4486 | ||
e5fa8140 AZ |
4487 | if (q->nr_requests == nr) |
4488 | return 0; | |
4489 | ||
70f36b60 | 4490 | blk_mq_freeze_queue(q); |
24f5a90f | 4491 | blk_mq_quiesce_queue(q); |
70f36b60 | 4492 | |
e3a2b3f9 JA |
4493 | ret = 0; |
4494 | queue_for_each_hw_ctx(q, hctx, i) { | |
e9137d4b KB |
4495 | if (!hctx->tags) |
4496 | continue; | |
bd166ef1 JA |
4497 | /* |
4498 | * If we're using an MQ scheduler, just update the scheduler | |
4499 | * queue depth. This is similar to what the old code would do. | |
4500 | */ | |
f6adcef5 | 4501 | if (hctx->sched_tags) { |
70f36b60 | 4502 | ret = blk_mq_tag_update_depth(hctx, &hctx->sched_tags, |
f6adcef5 | 4503 | nr, true); |
f6adcef5 JG |
4504 | } else { |
4505 | ret = blk_mq_tag_update_depth(hctx, &hctx->tags, nr, | |
4506 | false); | |
70f36b60 | 4507 | } |
e3a2b3f9 JA |
4508 | if (ret) |
4509 | break; | |
77f1e0a5 JA |
4510 | if (q->elevator && q->elevator->type->ops.depth_updated) |
4511 | q->elevator->type->ops.depth_updated(hctx); | |
e3a2b3f9 | 4512 | } |
d97e594c | 4513 | if (!ret) { |
e3a2b3f9 | 4514 | q->nr_requests = nr; |
079a2e3e | 4515 | if (blk_mq_is_shared_tags(set->flags)) { |
8fa04464 | 4516 | if (q->elevator) |
079a2e3e | 4517 | blk_mq_tag_update_sched_shared_tags(q); |
8fa04464 | 4518 | else |
079a2e3e | 4519 | blk_mq_tag_resize_shared_tags(set, nr); |
8fa04464 | 4520 | } |
d97e594c | 4521 | } |
e3a2b3f9 | 4522 | |
24f5a90f | 4523 | blk_mq_unquiesce_queue(q); |
70f36b60 | 4524 | blk_mq_unfreeze_queue(q); |
70f36b60 | 4525 | |
e3a2b3f9 JA |
4526 | return ret; |
4527 | } | |
4528 | ||
d48ece20 JW |
4529 | /* |
4530 | * request_queue and elevator_type pair. | |
4531 | * It is just used by __blk_mq_update_nr_hw_queues to cache | |
4532 | * the elevator_type associated with a request_queue. | |
4533 | */ | |
4534 | struct blk_mq_qe_pair { | |
4535 | struct list_head node; | |
4536 | struct request_queue *q; | |
4537 | struct elevator_type *type; | |
4538 | }; | |
4539 | ||
4540 | /* | |
4541 | * Cache the elevator_type in qe pair list and switch the | |
4542 | * io scheduler to 'none' | |
4543 | */ | |
4544 | static bool blk_mq_elv_switch_none(struct list_head *head, | |
4545 | struct request_queue *q) | |
4546 | { | |
4547 | struct blk_mq_qe_pair *qe; | |
4548 | ||
4549 | if (!q->elevator) | |
4550 | return true; | |
4551 | ||
4552 | qe = kmalloc(sizeof(*qe), GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY); | |
4553 | if (!qe) | |
4554 | return false; | |
4555 | ||
5fd7a84a ML |
4556 | /* q->elevator needs protection from ->sysfs_lock */ |
4557 | mutex_lock(&q->sysfs_lock); | |
4558 | ||
d48ece20 JW |
4559 | INIT_LIST_HEAD(&qe->node); |
4560 | qe->q = q; | |
4561 | qe->type = q->elevator->type; | |
4562 | list_add(&qe->node, head); | |
4563 | ||
d48ece20 | 4564 | /* |
8237c01f | 4565 | * After elevator_switch, the previous elevator_queue will be |
d48ece20 JW |
4566 | * released by elevator_release. The reference of the io scheduler |
4567 | * module get by elevator_get will also be put. So we need to get | |
4568 | * a reference of the io scheduler module here to prevent it to be | |
4569 | * removed. | |
4570 | */ | |
4571 | __module_get(qe->type->elevator_owner); | |
8237c01f | 4572 | elevator_switch(q, NULL); |
d48ece20 JW |
4573 | mutex_unlock(&q->sysfs_lock); |
4574 | ||
4575 | return true; | |
4576 | } | |
4577 | ||
4a3b666e JK |
4578 | static struct blk_mq_qe_pair *blk_lookup_qe_pair(struct list_head *head, |
4579 | struct request_queue *q) | |
d48ece20 JW |
4580 | { |
4581 | struct blk_mq_qe_pair *qe; | |
d48ece20 JW |
4582 | |
4583 | list_for_each_entry(qe, head, node) | |
4a3b666e JK |
4584 | if (qe->q == q) |
4585 | return qe; | |
d48ece20 | 4586 | |
4a3b666e JK |
4587 | return NULL; |
4588 | } | |
d48ece20 | 4589 | |
4a3b666e JK |
4590 | static void blk_mq_elv_switch_back(struct list_head *head, |
4591 | struct request_queue *q) | |
4592 | { | |
4593 | struct blk_mq_qe_pair *qe; | |
4594 | struct elevator_type *t; | |
4595 | ||
4596 | qe = blk_lookup_qe_pair(head, q); | |
4597 | if (!qe) | |
4598 | return; | |
4599 | t = qe->type; | |
d48ece20 JW |
4600 | list_del(&qe->node); |
4601 | kfree(qe); | |
4602 | ||
4603 | mutex_lock(&q->sysfs_lock); | |
8237c01f | 4604 | elevator_switch(q, t); |
d48ece20 JW |
4605 | mutex_unlock(&q->sysfs_lock); |
4606 | } | |
4607 | ||
e4dc2b32 KB |
4608 | static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, |
4609 | int nr_hw_queues) | |
868f2f0b KB |
4610 | { |
4611 | struct request_queue *q; | |
d48ece20 | 4612 | LIST_HEAD(head); |
e01ad46d | 4613 | int prev_nr_hw_queues; |
868f2f0b | 4614 | |
705cda97 BVA |
4615 | lockdep_assert_held(&set->tag_list_lock); |
4616 | ||
392546ae | 4617 | if (set->nr_maps == 1 && nr_hw_queues > nr_cpu_ids) |
868f2f0b | 4618 | nr_hw_queues = nr_cpu_ids; |
fe35ec58 WZ |
4619 | if (nr_hw_queues < 1) |
4620 | return; | |
4621 | if (set->nr_maps == 1 && nr_hw_queues == set->nr_hw_queues) | |
868f2f0b KB |
4622 | return; |
4623 | ||
4624 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
4625 | blk_mq_freeze_queue(q); | |
d48ece20 JW |
4626 | /* |
4627 | * Switch IO scheduler to 'none', cleaning up the data associated | |
4628 | * with the previous scheduler. We will switch back once we are done | |
4629 | * updating the new sw to hw queue mappings. | |
4630 | */ | |
4631 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
4632 | if (!blk_mq_elv_switch_none(&head, q)) | |
4633 | goto switch_back; | |
868f2f0b | 4634 | |
477e19de JW |
4635 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
4636 | blk_mq_debugfs_unregister_hctxs(q); | |
eaa870f9 | 4637 | blk_mq_sysfs_unregister_hctxs(q); |
477e19de JW |
4638 | } |
4639 | ||
a2584e43 | 4640 | prev_nr_hw_queues = set->nr_hw_queues; |
f7e76dbc BVA |
4641 | if (blk_mq_realloc_tag_set_tags(set, set->nr_hw_queues, nr_hw_queues) < |
4642 | 0) | |
4643 | goto reregister; | |
4644 | ||
868f2f0b | 4645 | set->nr_hw_queues = nr_hw_queues; |
e01ad46d | 4646 | fallback: |
aa880ad6 | 4647 | blk_mq_update_queue_map(set); |
868f2f0b KB |
4648 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
4649 | blk_mq_realloc_hw_ctxs(set, q); | |
42ee3061 | 4650 | blk_mq_update_poll_flag(q); |
e01ad46d | 4651 | if (q->nr_hw_queues != set->nr_hw_queues) { |
a846a8e6 YB |
4652 | int i = prev_nr_hw_queues; |
4653 | ||
e01ad46d JW |
4654 | pr_warn("Increasing nr_hw_queues to %d fails, fallback to %d\n", |
4655 | nr_hw_queues, prev_nr_hw_queues); | |
a846a8e6 YB |
4656 | for (; i < set->nr_hw_queues; i++) |
4657 | __blk_mq_free_map_and_rqs(set, i); | |
4658 | ||
e01ad46d | 4659 | set->nr_hw_queues = prev_nr_hw_queues; |
7d76f856 | 4660 | blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]); |
e01ad46d JW |
4661 | goto fallback; |
4662 | } | |
477e19de JW |
4663 | blk_mq_map_swqueue(q); |
4664 | } | |
4665 | ||
f7e76dbc | 4666 | reregister: |
477e19de | 4667 | list_for_each_entry(q, &set->tag_list, tag_set_list) { |
eaa870f9 | 4668 | blk_mq_sysfs_register_hctxs(q); |
477e19de | 4669 | blk_mq_debugfs_register_hctxs(q); |
868f2f0b KB |
4670 | } |
4671 | ||
d48ece20 JW |
4672 | switch_back: |
4673 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
4674 | blk_mq_elv_switch_back(&head, q); | |
4675 | ||
868f2f0b KB |
4676 | list_for_each_entry(q, &set->tag_list, tag_set_list) |
4677 | blk_mq_unfreeze_queue(q); | |
4678 | } | |
e4dc2b32 KB |
4679 | |
4680 | void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues) | |
4681 | { | |
4682 | mutex_lock(&set->tag_list_lock); | |
4683 | __blk_mq_update_nr_hw_queues(set, nr_hw_queues); | |
4684 | mutex_unlock(&set->tag_list_lock); | |
4685 | } | |
868f2f0b KB |
4686 | EXPORT_SYMBOL_GPL(blk_mq_update_nr_hw_queues); |
4687 | ||
34dbad5d OS |
4688 | /* Enable polling stats and return whether they were already enabled. */ |
4689 | static bool blk_poll_stats_enable(struct request_queue *q) | |
4690 | { | |
48b5c1fb | 4691 | if (q->poll_stat) |
34dbad5d | 4692 | return true; |
48b5c1fb JA |
4693 | |
4694 | return blk_stats_alloc_enable(q); | |
34dbad5d OS |
4695 | } |
4696 | ||
4697 | static void blk_mq_poll_stats_start(struct request_queue *q) | |
4698 | { | |
4699 | /* | |
4700 | * We don't arm the callback if polling stats are not enabled or the | |
4701 | * callback is already active. | |
4702 | */ | |
48b5c1fb | 4703 | if (!q->poll_stat || blk_stat_is_active(q->poll_cb)) |
34dbad5d OS |
4704 | return; |
4705 | ||
4706 | blk_stat_activate_msecs(q->poll_cb, 100); | |
4707 | } | |
4708 | ||
4709 | static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb) | |
4710 | { | |
4711 | struct request_queue *q = cb->data; | |
720b8ccc | 4712 | int bucket; |
34dbad5d | 4713 | |
720b8ccc SB |
4714 | for (bucket = 0; bucket < BLK_MQ_POLL_STATS_BKTS; bucket++) { |
4715 | if (cb->stat[bucket].nr_samples) | |
4716 | q->poll_stat[bucket] = cb->stat[bucket]; | |
4717 | } | |
34dbad5d OS |
4718 | } |
4719 | ||
64f1c21e | 4720 | static unsigned long blk_mq_poll_nsecs(struct request_queue *q, |
64f1c21e JA |
4721 | struct request *rq) |
4722 | { | |
64f1c21e | 4723 | unsigned long ret = 0; |
720b8ccc | 4724 | int bucket; |
64f1c21e JA |
4725 | |
4726 | /* | |
4727 | * If stats collection isn't on, don't sleep but turn it on for | |
4728 | * future users | |
4729 | */ | |
34dbad5d | 4730 | if (!blk_poll_stats_enable(q)) |
64f1c21e JA |
4731 | return 0; |
4732 | ||
64f1c21e JA |
4733 | /* |
4734 | * As an optimistic guess, use half of the mean service time | |
4735 | * for this type of request. We can (and should) make this smarter. | |
4736 | * For instance, if the completion latencies are tight, we can | |
4737 | * get closer than just half the mean. This is especially | |
4738 | * important on devices where the completion latencies are longer | |
720b8ccc SB |
4739 | * than ~10 usec. We do use the stats for the relevant IO size |
4740 | * if available which does lead to better estimates. | |
64f1c21e | 4741 | */ |
720b8ccc SB |
4742 | bucket = blk_mq_poll_stats_bkt(rq); |
4743 | if (bucket < 0) | |
4744 | return ret; | |
4745 | ||
4746 | if (q->poll_stat[bucket].nr_samples) | |
4747 | ret = (q->poll_stat[bucket].mean + 1) / 2; | |
64f1c21e JA |
4748 | |
4749 | return ret; | |
4750 | } | |
4751 | ||
c6699d6f | 4752 | static bool blk_mq_poll_hybrid(struct request_queue *q, blk_qc_t qc) |
06426adf | 4753 | { |
c6699d6f CH |
4754 | struct blk_mq_hw_ctx *hctx = blk_qc_to_hctx(q, qc); |
4755 | struct request *rq = blk_qc_to_rq(hctx, qc); | |
06426adf JA |
4756 | struct hrtimer_sleeper hs; |
4757 | enum hrtimer_mode mode; | |
64f1c21e | 4758 | unsigned int nsecs; |
06426adf JA |
4759 | ktime_t kt; |
4760 | ||
c6699d6f CH |
4761 | /* |
4762 | * If a request has completed on queue that uses an I/O scheduler, we | |
4763 | * won't get back a request from blk_qc_to_rq. | |
4764 | */ | |
4765 | if (!rq || (rq->rq_flags & RQF_MQ_POLL_SLEPT)) | |
64f1c21e JA |
4766 | return false; |
4767 | ||
4768 | /* | |
1052b8ac | 4769 | * If we get here, hybrid polling is enabled. Hence poll_nsec can be: |
64f1c21e | 4770 | * |
64f1c21e JA |
4771 | * 0: use half of prev avg |
4772 | * >0: use this specific value | |
4773 | */ | |
1052b8ac | 4774 | if (q->poll_nsec > 0) |
64f1c21e JA |
4775 | nsecs = q->poll_nsec; |
4776 | else | |
cae740a0 | 4777 | nsecs = blk_mq_poll_nsecs(q, rq); |
64f1c21e JA |
4778 | |
4779 | if (!nsecs) | |
06426adf JA |
4780 | return false; |
4781 | ||
76a86f9d | 4782 | rq->rq_flags |= RQF_MQ_POLL_SLEPT; |
06426adf JA |
4783 | |
4784 | /* | |
4785 | * This will be replaced with the stats tracking code, using | |
4786 | * 'avg_completion_time / 2' as the pre-sleep target. | |
4787 | */ | |
8b0e1953 | 4788 | kt = nsecs; |
06426adf JA |
4789 | |
4790 | mode = HRTIMER_MODE_REL; | |
dbc1625f | 4791 | hrtimer_init_sleeper_on_stack(&hs, CLOCK_MONOTONIC, mode); |
06426adf JA |
4792 | hrtimer_set_expires(&hs.timer, kt); |
4793 | ||
06426adf | 4794 | do { |
5a61c363 | 4795 | if (blk_mq_rq_state(rq) == MQ_RQ_COMPLETE) |
06426adf JA |
4796 | break; |
4797 | set_current_state(TASK_UNINTERRUPTIBLE); | |
9dd8813e | 4798 | hrtimer_sleeper_start_expires(&hs, mode); |
06426adf JA |
4799 | if (hs.task) |
4800 | io_schedule(); | |
4801 | hrtimer_cancel(&hs.timer); | |
4802 | mode = HRTIMER_MODE_ABS; | |
4803 | } while (hs.task && !signal_pending(current)); | |
4804 | ||
4805 | __set_current_state(TASK_RUNNING); | |
4806 | destroy_hrtimer_on_stack(&hs.timer); | |
1052b8ac | 4807 | |
06426adf | 4808 | /* |
c6699d6f CH |
4809 | * If we sleep, have the caller restart the poll loop to reset the |
4810 | * state. Like for the other success return cases, the caller is | |
4811 | * responsible for checking if the IO completed. If the IO isn't | |
4812 | * complete, we'll get called again and will go straight to the busy | |
4813 | * poll loop. | |
06426adf | 4814 | */ |
06426adf JA |
4815 | return true; |
4816 | } | |
06426adf | 4817 | |
c6699d6f | 4818 | static int blk_mq_poll_classic(struct request_queue *q, blk_qc_t cookie, |
5a72e899 | 4819 | struct io_comp_batch *iob, unsigned int flags) |
bbd7bb70 | 4820 | { |
c6699d6f CH |
4821 | struct blk_mq_hw_ctx *hctx = blk_qc_to_hctx(q, cookie); |
4822 | long state = get_current_state(); | |
4823 | int ret; | |
bbd7bb70 | 4824 | |
aa61bec3 | 4825 | do { |
5a72e899 | 4826 | ret = q->mq_ops->poll(hctx, iob); |
bbd7bb70 | 4827 | if (ret > 0) { |
849a3700 | 4828 | __set_current_state(TASK_RUNNING); |
85f4d4b6 | 4829 | return ret; |
bbd7bb70 JA |
4830 | } |
4831 | ||
4832 | if (signal_pending_state(state, current)) | |
849a3700 | 4833 | __set_current_state(TASK_RUNNING); |
b03fbd4f | 4834 | if (task_is_running(current)) |
85f4d4b6 | 4835 | return 1; |
c6699d6f | 4836 | |
ef99b2d3 | 4837 | if (ret < 0 || (flags & BLK_POLL_ONESHOT)) |
bbd7bb70 JA |
4838 | break; |
4839 | cpu_relax(); | |
aa61bec3 | 4840 | } while (!need_resched()); |
bbd7bb70 | 4841 | |
67b4110f | 4842 | __set_current_state(TASK_RUNNING); |
85f4d4b6 | 4843 | return 0; |
bbd7bb70 | 4844 | } |
1052b8ac | 4845 | |
5a72e899 JA |
4846 | int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, struct io_comp_batch *iob, |
4847 | unsigned int flags) | |
1052b8ac | 4848 | { |
d729cf9a CH |
4849 | if (!(flags & BLK_POLL_NOSLEEP) && |
4850 | q->poll_nsec != BLK_MQ_POLL_CLASSIC) { | |
c6699d6f | 4851 | if (blk_mq_poll_hybrid(q, cookie)) |
85f4d4b6 | 4852 | return 1; |
c6699d6f | 4853 | } |
5a72e899 | 4854 | return blk_mq_poll_classic(q, cookie, iob, flags); |
bbd7bb70 JA |
4855 | } |
4856 | ||
9cf2bab6 JA |
4857 | unsigned int blk_mq_rq_cpu(struct request *rq) |
4858 | { | |
4859 | return rq->mq_ctx->cpu; | |
4860 | } | |
4861 | EXPORT_SYMBOL(blk_mq_rq_cpu); | |
4862 | ||
2a19b28f ML |
4863 | void blk_mq_cancel_work_sync(struct request_queue *q) |
4864 | { | |
4865 | if (queue_is_mq(q)) { | |
4866 | struct blk_mq_hw_ctx *hctx; | |
4f481208 | 4867 | unsigned long i; |
2a19b28f ML |
4868 | |
4869 | cancel_delayed_work_sync(&q->requeue_work); | |
4870 | ||
4871 | queue_for_each_hw_ctx(q, hctx, i) | |
4872 | cancel_delayed_work_sync(&hctx->run_work); | |
4873 | } | |
4874 | } | |
4875 | ||
320ae51f JA |
4876 | static int __init blk_mq_init(void) |
4877 | { | |
c3077b5d CH |
4878 | int i; |
4879 | ||
4880 | for_each_possible_cpu(i) | |
f9ab4918 | 4881 | init_llist_head(&per_cpu(blk_cpu_done, i)); |
c3077b5d CH |
4882 | open_softirq(BLOCK_SOFTIRQ, blk_done_softirq); |
4883 | ||
4884 | cpuhp_setup_state_nocalls(CPUHP_BLOCK_SOFTIRQ_DEAD, | |
4885 | "block/softirq:dead", NULL, | |
4886 | blk_softirq_cpu_dead); | |
9467f859 TG |
4887 | cpuhp_setup_state_multi(CPUHP_BLK_MQ_DEAD, "block/mq:dead", NULL, |
4888 | blk_mq_hctx_notify_dead); | |
bf0beec0 ML |
4889 | cpuhp_setup_state_multi(CPUHP_AP_BLK_MQ_ONLINE, "block/mq:online", |
4890 | blk_mq_hctx_notify_online, | |
4891 | blk_mq_hctx_notify_offline); | |
320ae51f JA |
4892 | return 0; |
4893 | } | |
4894 | subsys_initcall(blk_mq_init); |