Commit | Line | Data |
---|---|---|
75bb4625 JA |
1 | /* |
2 | * Block multiqueue core code | |
3 | * | |
4 | * Copyright (C) 2013-2014 Jens Axboe | |
5 | * Copyright (C) 2013-2014 Christoph Hellwig | |
6 | */ | |
320ae51f JA |
7 | #include <linux/kernel.h> |
8 | #include <linux/module.h> | |
9 | #include <linux/backing-dev.h> | |
10 | #include <linux/bio.h> | |
11 | #include <linux/blkdev.h> | |
f75782e4 | 12 | #include <linux/kmemleak.h> |
320ae51f JA |
13 | #include <linux/mm.h> |
14 | #include <linux/init.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/workqueue.h> | |
17 | #include <linux/smp.h> | |
18 | #include <linux/llist.h> | |
19 | #include <linux/list_sort.h> | |
20 | #include <linux/cpu.h> | |
21 | #include <linux/cache.h> | |
22 | #include <linux/sched/sysctl.h> | |
23 | #include <linux/delay.h> | |
aedcd72f | 24 | #include <linux/crash_dump.h> |
88c7b2b7 | 25 | #include <linux/prefetch.h> |
320ae51f JA |
26 | |
27 | #include <trace/events/block.h> | |
28 | ||
29 | #include <linux/blk-mq.h> | |
30 | #include "blk.h" | |
31 | #include "blk-mq.h" | |
32 | #include "blk-mq-tag.h" | |
33 | ||
34 | static DEFINE_MUTEX(all_q_mutex); | |
35 | static LIST_HEAD(all_q_list); | |
36 | ||
320ae51f JA |
37 | /* |
38 | * Check if any of the ctx's have pending work in this hardware queue | |
39 | */ | |
40 | static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx) | |
41 | { | |
88459642 | 42 | return sbitmap_any_bit_set(&hctx->ctx_map); |
1429d7c9 JA |
43 | } |
44 | ||
320ae51f JA |
45 | /* |
46 | * Mark this ctx as having pending work in this hardware queue | |
47 | */ | |
48 | static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, | |
49 | struct blk_mq_ctx *ctx) | |
50 | { | |
88459642 OS |
51 | if (!sbitmap_test_bit(&hctx->ctx_map, ctx->index_hw)) |
52 | sbitmap_set_bit(&hctx->ctx_map, ctx->index_hw); | |
1429d7c9 JA |
53 | } |
54 | ||
55 | static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, | |
56 | struct blk_mq_ctx *ctx) | |
57 | { | |
88459642 | 58 | sbitmap_clear_bit(&hctx->ctx_map, ctx->index_hw); |
320ae51f JA |
59 | } |
60 | ||
b4c6a028 | 61 | void blk_mq_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 62 | { |
4ecd4fef | 63 | int freeze_depth; |
cddd5d17 | 64 | |
4ecd4fef CH |
65 | freeze_depth = atomic_inc_return(&q->mq_freeze_depth); |
66 | if (freeze_depth == 1) { | |
3ef28e83 | 67 | percpu_ref_kill(&q->q_usage_counter); |
b94ec296 | 68 | blk_mq_run_hw_queues(q, false); |
cddd5d17 | 69 | } |
f3af020b | 70 | } |
b4c6a028 | 71 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start); |
f3af020b TH |
72 | |
73 | static void blk_mq_freeze_queue_wait(struct request_queue *q) | |
74 | { | |
3ef28e83 | 75 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter)); |
43a5e4e2 ML |
76 | } |
77 | ||
f3af020b TH |
78 | /* |
79 | * Guarantee no request is in use, so we can change any data structure of | |
80 | * the queue afterward. | |
81 | */ | |
3ef28e83 | 82 | void blk_freeze_queue(struct request_queue *q) |
f3af020b | 83 | { |
3ef28e83 DW |
84 | /* |
85 | * In the !blk_mq case we are only calling this to kill the | |
86 | * q_usage_counter, otherwise this increases the freeze depth | |
87 | * and waits for it to return to zero. For this reason there is | |
88 | * no blk_unfreeze_queue(), and blk_freeze_queue() is not | |
89 | * exported to drivers as the only user for unfreeze is blk_mq. | |
90 | */ | |
f3af020b TH |
91 | blk_mq_freeze_queue_start(q); |
92 | blk_mq_freeze_queue_wait(q); | |
93 | } | |
3ef28e83 DW |
94 | |
95 | void blk_mq_freeze_queue(struct request_queue *q) | |
96 | { | |
97 | /* | |
98 | * ...just an alias to keep freeze and unfreeze actions balanced | |
99 | * in the blk_mq_* namespace | |
100 | */ | |
101 | blk_freeze_queue(q); | |
102 | } | |
c761d96b | 103 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue); |
f3af020b | 104 | |
b4c6a028 | 105 | void blk_mq_unfreeze_queue(struct request_queue *q) |
320ae51f | 106 | { |
4ecd4fef | 107 | int freeze_depth; |
320ae51f | 108 | |
4ecd4fef CH |
109 | freeze_depth = atomic_dec_return(&q->mq_freeze_depth); |
110 | WARN_ON_ONCE(freeze_depth < 0); | |
111 | if (!freeze_depth) { | |
3ef28e83 | 112 | percpu_ref_reinit(&q->q_usage_counter); |
320ae51f | 113 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 114 | } |
320ae51f | 115 | } |
b4c6a028 | 116 | EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
320ae51f | 117 | |
aed3ea94 JA |
118 | void blk_mq_wake_waiters(struct request_queue *q) |
119 | { | |
120 | struct blk_mq_hw_ctx *hctx; | |
121 | unsigned int i; | |
122 | ||
123 | queue_for_each_hw_ctx(q, hctx, i) | |
124 | if (blk_mq_hw_queue_mapped(hctx)) | |
125 | blk_mq_tag_wakeup_all(hctx->tags, true); | |
3fd5940c KB |
126 | |
127 | /* | |
128 | * If we are called because the queue has now been marked as | |
129 | * dying, we need to ensure that processes currently waiting on | |
130 | * the queue are notified as well. | |
131 | */ | |
132 | wake_up_all(&q->mq_freeze_wq); | |
aed3ea94 JA |
133 | } |
134 | ||
320ae51f JA |
135 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) |
136 | { | |
137 | return blk_mq_has_free_tags(hctx->tags); | |
138 | } | |
139 | EXPORT_SYMBOL(blk_mq_can_queue); | |
140 | ||
94eddfbe | 141 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
cc6e3b10 MC |
142 | struct request *rq, int op, |
143 | unsigned int op_flags) | |
320ae51f | 144 | { |
94eddfbe | 145 | if (blk_queue_io_stat(q)) |
cc6e3b10 | 146 | op_flags |= REQ_IO_STAT; |
94eddfbe | 147 | |
af76e555 CH |
148 | INIT_LIST_HEAD(&rq->queuelist); |
149 | /* csd/requeue_work/fifo_time is initialized before use */ | |
150 | rq->q = q; | |
320ae51f | 151 | rq->mq_ctx = ctx; |
cc6e3b10 | 152 | req_set_op_attrs(rq, op, op_flags); |
af76e555 CH |
153 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
154 | rq->cpu = -1; | |
af76e555 CH |
155 | INIT_HLIST_NODE(&rq->hash); |
156 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
157 | rq->rq_disk = NULL; |
158 | rq->part = NULL; | |
3ee32372 | 159 | rq->start_time = jiffies; |
af76e555 CH |
160 | #ifdef CONFIG_BLK_CGROUP |
161 | rq->rl = NULL; | |
0fec08b4 | 162 | set_start_time_ns(rq); |
af76e555 CH |
163 | rq->io_start_time_ns = 0; |
164 | #endif | |
165 | rq->nr_phys_segments = 0; | |
166 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
167 | rq->nr_integrity_segments = 0; | |
168 | #endif | |
af76e555 CH |
169 | rq->special = NULL; |
170 | /* tag was already set */ | |
171 | rq->errors = 0; | |
af76e555 | 172 | |
6f4a1626 TB |
173 | rq->cmd = rq->__cmd; |
174 | ||
af76e555 CH |
175 | rq->extra_len = 0; |
176 | rq->sense_len = 0; | |
177 | rq->resid_len = 0; | |
178 | rq->sense = NULL; | |
179 | ||
af76e555 | 180 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
181 | rq->timeout = 0; |
182 | ||
af76e555 CH |
183 | rq->end_io = NULL; |
184 | rq->end_io_data = NULL; | |
185 | rq->next_rq = NULL; | |
186 | ||
d9d8c5c4 | 187 | ctx->rq_dispatched[rw_is_sync(op, op_flags)]++; |
320ae51f JA |
188 | } |
189 | ||
5dee8577 | 190 | static struct request * |
cc6e3b10 | 191 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int op, int op_flags) |
5dee8577 CH |
192 | { |
193 | struct request *rq; | |
194 | unsigned int tag; | |
195 | ||
cb96a42c | 196 | tag = blk_mq_get_tag(data); |
5dee8577 | 197 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 198 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 199 | |
cb96a42c | 200 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 201 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 202 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
203 | } |
204 | ||
205 | rq->tag = tag; | |
cc6e3b10 | 206 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, op, op_flags); |
5dee8577 CH |
207 | return rq; |
208 | } | |
209 | ||
210 | return NULL; | |
211 | } | |
212 | ||
6f3b0e8b CH |
213 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, |
214 | unsigned int flags) | |
320ae51f | 215 | { |
d852564f CH |
216 | struct blk_mq_ctx *ctx; |
217 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 218 | struct request *rq; |
cb96a42c | 219 | struct blk_mq_alloc_data alloc_data; |
a492f075 | 220 | int ret; |
320ae51f | 221 | |
6f3b0e8b | 222 | ret = blk_queue_enter(q, flags & BLK_MQ_REQ_NOWAIT); |
a492f075 JL |
223 | if (ret) |
224 | return ERR_PTR(ret); | |
320ae51f | 225 | |
d852564f | 226 | ctx = blk_mq_get_ctx(q); |
7d7e0f90 | 227 | hctx = blk_mq_map_queue(q, ctx->cpu); |
6f3b0e8b | 228 | blk_mq_set_alloc_data(&alloc_data, q, flags, ctx, hctx); |
cc6e3b10 | 229 | rq = __blk_mq_alloc_request(&alloc_data, rw, 0); |
d852564f | 230 | blk_mq_put_ctx(ctx); |
841bac2c | 231 | |
c76541a9 | 232 | if (!rq) { |
3ef28e83 | 233 | blk_queue_exit(q); |
a492f075 | 234 | return ERR_PTR(-EWOULDBLOCK); |
c76541a9 | 235 | } |
0c4de0f3 CH |
236 | |
237 | rq->__data_len = 0; | |
238 | rq->__sector = (sector_t) -1; | |
239 | rq->bio = rq->biotail = NULL; | |
320ae51f JA |
240 | return rq; |
241 | } | |
4bb659b1 | 242 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 243 | |
1f5bd336 ML |
244 | struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int rw, |
245 | unsigned int flags, unsigned int hctx_idx) | |
246 | { | |
247 | struct blk_mq_hw_ctx *hctx; | |
248 | struct blk_mq_ctx *ctx; | |
249 | struct request *rq; | |
250 | struct blk_mq_alloc_data alloc_data; | |
251 | int ret; | |
252 | ||
253 | /* | |
254 | * If the tag allocator sleeps we could get an allocation for a | |
255 | * different hardware context. No need to complicate the low level | |
256 | * allocator for this for the rare use case of a command tied to | |
257 | * a specific queue. | |
258 | */ | |
259 | if (WARN_ON_ONCE(!(flags & BLK_MQ_REQ_NOWAIT))) | |
260 | return ERR_PTR(-EINVAL); | |
261 | ||
262 | if (hctx_idx >= q->nr_hw_queues) | |
263 | return ERR_PTR(-EIO); | |
264 | ||
265 | ret = blk_queue_enter(q, true); | |
266 | if (ret) | |
267 | return ERR_PTR(ret); | |
268 | ||
c8712c6a CH |
269 | /* |
270 | * Check if the hardware context is actually mapped to anything. | |
271 | * If not tell the caller that it should skip this queue. | |
272 | */ | |
1f5bd336 | 273 | hctx = q->queue_hw_ctx[hctx_idx]; |
c8712c6a CH |
274 | if (!blk_mq_hw_queue_mapped(hctx)) { |
275 | ret = -EXDEV; | |
276 | goto out_queue_exit; | |
277 | } | |
1f5bd336 ML |
278 | ctx = __blk_mq_get_ctx(q, cpumask_first(hctx->cpumask)); |
279 | ||
280 | blk_mq_set_alloc_data(&alloc_data, q, flags, ctx, hctx); | |
281 | rq = __blk_mq_alloc_request(&alloc_data, rw, 0); | |
282 | if (!rq) { | |
c8712c6a CH |
283 | ret = -EWOULDBLOCK; |
284 | goto out_queue_exit; | |
1f5bd336 ML |
285 | } |
286 | ||
287 | return rq; | |
c8712c6a CH |
288 | |
289 | out_queue_exit: | |
290 | blk_queue_exit(q); | |
291 | return ERR_PTR(ret); | |
1f5bd336 ML |
292 | } |
293 | EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx); | |
294 | ||
320ae51f JA |
295 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
296 | struct blk_mq_ctx *ctx, struct request *rq) | |
297 | { | |
298 | const int tag = rq->tag; | |
299 | struct request_queue *q = rq->q; | |
300 | ||
0d2602ca JA |
301 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
302 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 303 | rq->cmd_flags = 0; |
0d2602ca | 304 | |
af76e555 | 305 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
40aabb67 | 306 | blk_mq_put_tag(hctx, ctx, tag); |
3ef28e83 | 307 | blk_queue_exit(q); |
320ae51f JA |
308 | } |
309 | ||
7c7f2f2b | 310 | void blk_mq_free_hctx_request(struct blk_mq_hw_ctx *hctx, struct request *rq) |
320ae51f JA |
311 | { |
312 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
320ae51f JA |
313 | |
314 | ctx->rq_completed[rq_is_sync(rq)]++; | |
320ae51f | 315 | __blk_mq_free_request(hctx, ctx, rq); |
7c7f2f2b JA |
316 | |
317 | } | |
318 | EXPORT_SYMBOL_GPL(blk_mq_free_hctx_request); | |
319 | ||
320 | void blk_mq_free_request(struct request *rq) | |
321 | { | |
7d7e0f90 | 322 | blk_mq_free_hctx_request(blk_mq_map_queue(rq->q, rq->mq_ctx->cpu), rq); |
320ae51f | 323 | } |
1a3b595a | 324 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 325 | |
c8a446ad | 326 | inline void __blk_mq_end_request(struct request *rq, int error) |
320ae51f | 327 | { |
0d11e6ac ML |
328 | blk_account_io_done(rq); |
329 | ||
91b63639 | 330 | if (rq->end_io) { |
320ae51f | 331 | rq->end_io(rq, error); |
91b63639 CH |
332 | } else { |
333 | if (unlikely(blk_bidi_rq(rq))) | |
334 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 335 | blk_mq_free_request(rq); |
91b63639 | 336 | } |
320ae51f | 337 | } |
c8a446ad | 338 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 339 | |
c8a446ad | 340 | void blk_mq_end_request(struct request *rq, int error) |
63151a44 CH |
341 | { |
342 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
343 | BUG(); | |
c8a446ad | 344 | __blk_mq_end_request(rq, error); |
63151a44 | 345 | } |
c8a446ad | 346 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 347 | |
30a91cb4 | 348 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 349 | { |
3d6efbf6 | 350 | struct request *rq = data; |
320ae51f | 351 | |
30a91cb4 | 352 | rq->q->softirq_done_fn(rq); |
320ae51f | 353 | } |
320ae51f | 354 | |
ed851860 | 355 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
356 | { |
357 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 358 | bool shared = false; |
320ae51f JA |
359 | int cpu; |
360 | ||
38535201 | 361 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
362 | rq->q->softirq_done_fn(rq); |
363 | return; | |
364 | } | |
320ae51f JA |
365 | |
366 | cpu = get_cpu(); | |
38535201 CH |
367 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
368 | shared = cpus_share_cache(cpu, ctx->cpu); | |
369 | ||
370 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 371 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
372 | rq->csd.info = rq; |
373 | rq->csd.flags = 0; | |
c46fff2a | 374 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 375 | } else { |
30a91cb4 | 376 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 377 | } |
320ae51f JA |
378 | put_cpu(); |
379 | } | |
30a91cb4 | 380 | |
1fa8cc52 | 381 | static void __blk_mq_complete_request(struct request *rq) |
ed851860 JA |
382 | { |
383 | struct request_queue *q = rq->q; | |
384 | ||
385 | if (!q->softirq_done_fn) | |
c8a446ad | 386 | blk_mq_end_request(rq, rq->errors); |
ed851860 JA |
387 | else |
388 | blk_mq_ipi_complete_request(rq); | |
389 | } | |
390 | ||
30a91cb4 CH |
391 | /** |
392 | * blk_mq_complete_request - end I/O on a request | |
393 | * @rq: the request being processed | |
394 | * | |
395 | * Description: | |
396 | * Ends all I/O on a request. It does not handle partial completions. | |
397 | * The actual completion happens out-of-order, through a IPI handler. | |
398 | **/ | |
f4829a9b | 399 | void blk_mq_complete_request(struct request *rq, int error) |
30a91cb4 | 400 | { |
95f09684 JA |
401 | struct request_queue *q = rq->q; |
402 | ||
403 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 404 | return; |
f4829a9b CH |
405 | if (!blk_mark_rq_complete(rq)) { |
406 | rq->errors = error; | |
ed851860 | 407 | __blk_mq_complete_request(rq); |
f4829a9b | 408 | } |
30a91cb4 CH |
409 | } |
410 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 411 | |
973c0191 KB |
412 | int blk_mq_request_started(struct request *rq) |
413 | { | |
414 | return test_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
415 | } | |
416 | EXPORT_SYMBOL_GPL(blk_mq_request_started); | |
417 | ||
e2490073 | 418 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
419 | { |
420 | struct request_queue *q = rq->q; | |
421 | ||
422 | trace_block_rq_issue(q, rq); | |
423 | ||
742ee69b | 424 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
425 | if (unlikely(blk_bidi_rq(rq))) |
426 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 427 | |
2b8393b4 | 428 | blk_add_timer(rq); |
87ee7b11 | 429 | |
538b7534 JA |
430 | /* |
431 | * Ensure that ->deadline is visible before set the started | |
432 | * flag and clear the completed flag. | |
433 | */ | |
434 | smp_mb__before_atomic(); | |
435 | ||
87ee7b11 JA |
436 | /* |
437 | * Mark us as started and clear complete. Complete might have been | |
438 | * set if requeue raced with timeout, which then marked it as | |
439 | * complete. So be sure to clear complete again when we start | |
440 | * the request, otherwise we'll ignore the completion event. | |
441 | */ | |
4b570521 JA |
442 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
443 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
444 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
445 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
446 | |
447 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
448 | /* | |
449 | * Make sure space for the drain appears. We know we can do | |
450 | * this because max_hw_segments has been adjusted to be one | |
451 | * fewer than the device can handle. | |
452 | */ | |
453 | rq->nr_phys_segments++; | |
454 | } | |
320ae51f | 455 | } |
e2490073 | 456 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 457 | |
ed0791b2 | 458 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
459 | { |
460 | struct request_queue *q = rq->q; | |
461 | ||
462 | trace_block_rq_requeue(q, rq); | |
49f5baa5 | 463 | |
e2490073 CH |
464 | if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
465 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
466 | rq->nr_phys_segments--; | |
467 | } | |
320ae51f JA |
468 | } |
469 | ||
ed0791b2 CH |
470 | void blk_mq_requeue_request(struct request *rq) |
471 | { | |
ed0791b2 | 472 | __blk_mq_requeue_request(rq); |
ed0791b2 | 473 | |
ed0791b2 | 474 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 475 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
476 | } |
477 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
478 | ||
6fca6a61 CH |
479 | static void blk_mq_requeue_work(struct work_struct *work) |
480 | { | |
481 | struct request_queue *q = | |
2849450a | 482 | container_of(work, struct request_queue, requeue_work.work); |
6fca6a61 CH |
483 | LIST_HEAD(rq_list); |
484 | struct request *rq, *next; | |
485 | unsigned long flags; | |
486 | ||
487 | spin_lock_irqsave(&q->requeue_lock, flags); | |
488 | list_splice_init(&q->requeue_list, &rq_list); | |
489 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
490 | ||
491 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
492 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
493 | continue; | |
494 | ||
495 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
496 | list_del_init(&rq->queuelist); | |
497 | blk_mq_insert_request(rq, true, false, false); | |
498 | } | |
499 | ||
500 | while (!list_empty(&rq_list)) { | |
501 | rq = list_entry(rq_list.next, struct request, queuelist); | |
502 | list_del_init(&rq->queuelist); | |
503 | blk_mq_insert_request(rq, false, false, false); | |
504 | } | |
505 | ||
8b957415 JA |
506 | /* |
507 | * Use the start variant of queue running here, so that running | |
508 | * the requeue work will kick stopped queues. | |
509 | */ | |
510 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
511 | } |
512 | ||
513 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
514 | { | |
515 | struct request_queue *q = rq->q; | |
516 | unsigned long flags; | |
517 | ||
518 | /* | |
519 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
520 | * request head insertation from the workqueue. | |
521 | */ | |
522 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
523 | ||
524 | spin_lock_irqsave(&q->requeue_lock, flags); | |
525 | if (at_head) { | |
526 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
527 | list_add(&rq->queuelist, &q->requeue_list); | |
528 | } else { | |
529 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
530 | } | |
531 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
532 | } | |
533 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
534 | ||
c68ed59f KB |
535 | void blk_mq_cancel_requeue_work(struct request_queue *q) |
536 | { | |
2849450a | 537 | cancel_delayed_work_sync(&q->requeue_work); |
c68ed59f KB |
538 | } |
539 | EXPORT_SYMBOL_GPL(blk_mq_cancel_requeue_work); | |
540 | ||
6fca6a61 CH |
541 | void blk_mq_kick_requeue_list(struct request_queue *q) |
542 | { | |
2849450a | 543 | kblockd_schedule_delayed_work(&q->requeue_work, 0); |
6fca6a61 CH |
544 | } |
545 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
546 | ||
2849450a MS |
547 | void blk_mq_delay_kick_requeue_list(struct request_queue *q, |
548 | unsigned long msecs) | |
549 | { | |
550 | kblockd_schedule_delayed_work(&q->requeue_work, | |
551 | msecs_to_jiffies(msecs)); | |
552 | } | |
553 | EXPORT_SYMBOL(blk_mq_delay_kick_requeue_list); | |
554 | ||
1885b24d JA |
555 | void blk_mq_abort_requeue_list(struct request_queue *q) |
556 | { | |
557 | unsigned long flags; | |
558 | LIST_HEAD(rq_list); | |
559 | ||
560 | spin_lock_irqsave(&q->requeue_lock, flags); | |
561 | list_splice_init(&q->requeue_list, &rq_list); | |
562 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
563 | ||
564 | while (!list_empty(&rq_list)) { | |
565 | struct request *rq; | |
566 | ||
567 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
568 | list_del_init(&rq->queuelist); | |
569 | rq->errors = -EIO; | |
570 | blk_mq_end_request(rq, rq->errors); | |
571 | } | |
572 | } | |
573 | EXPORT_SYMBOL(blk_mq_abort_requeue_list); | |
574 | ||
0e62f51f JA |
575 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) |
576 | { | |
88c7b2b7 JA |
577 | if (tag < tags->nr_tags) { |
578 | prefetch(tags->rqs[tag]); | |
4ee86bab | 579 | return tags->rqs[tag]; |
88c7b2b7 | 580 | } |
4ee86bab HR |
581 | |
582 | return NULL; | |
24d2f903 CH |
583 | } |
584 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
585 | ||
320ae51f | 586 | struct blk_mq_timeout_data { |
46f92d42 CH |
587 | unsigned long next; |
588 | unsigned int next_set; | |
320ae51f JA |
589 | }; |
590 | ||
90415837 | 591 | void blk_mq_rq_timed_out(struct request *req, bool reserved) |
320ae51f | 592 | { |
46f92d42 CH |
593 | struct blk_mq_ops *ops = req->q->mq_ops; |
594 | enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER; | |
87ee7b11 JA |
595 | |
596 | /* | |
597 | * We know that complete is set at this point. If STARTED isn't set | |
598 | * anymore, then the request isn't active and the "timeout" should | |
599 | * just be ignored. This can happen due to the bitflag ordering. | |
600 | * Timeout first checks if STARTED is set, and if it is, assumes | |
601 | * the request is active. But if we race with completion, then | |
602 | * we both flags will get cleared. So check here again, and ignore | |
603 | * a timeout event with a request that isn't active. | |
604 | */ | |
46f92d42 CH |
605 | if (!test_bit(REQ_ATOM_STARTED, &req->atomic_flags)) |
606 | return; | |
87ee7b11 | 607 | |
46f92d42 | 608 | if (ops->timeout) |
0152fb6b | 609 | ret = ops->timeout(req, reserved); |
46f92d42 CH |
610 | |
611 | switch (ret) { | |
612 | case BLK_EH_HANDLED: | |
613 | __blk_mq_complete_request(req); | |
614 | break; | |
615 | case BLK_EH_RESET_TIMER: | |
616 | blk_add_timer(req); | |
617 | blk_clear_rq_complete(req); | |
618 | break; | |
619 | case BLK_EH_NOT_HANDLED: | |
620 | break; | |
621 | default: | |
622 | printk(KERN_ERR "block: bad eh return: %d\n", ret); | |
623 | break; | |
624 | } | |
87ee7b11 | 625 | } |
5b3f25fc | 626 | |
81481eb4 CH |
627 | static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, |
628 | struct request *rq, void *priv, bool reserved) | |
629 | { | |
630 | struct blk_mq_timeout_data *data = priv; | |
87ee7b11 | 631 | |
eb130dbf KB |
632 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
633 | /* | |
634 | * If a request wasn't started before the queue was | |
635 | * marked dying, kill it here or it'll go unnoticed. | |
636 | */ | |
a59e0f57 KB |
637 | if (unlikely(blk_queue_dying(rq->q))) { |
638 | rq->errors = -EIO; | |
639 | blk_mq_end_request(rq, rq->errors); | |
640 | } | |
46f92d42 | 641 | return; |
eb130dbf | 642 | } |
87ee7b11 | 643 | |
46f92d42 CH |
644 | if (time_after_eq(jiffies, rq->deadline)) { |
645 | if (!blk_mark_rq_complete(rq)) | |
0152fb6b | 646 | blk_mq_rq_timed_out(rq, reserved); |
46f92d42 CH |
647 | } else if (!data->next_set || time_after(data->next, rq->deadline)) { |
648 | data->next = rq->deadline; | |
649 | data->next_set = 1; | |
650 | } | |
87ee7b11 JA |
651 | } |
652 | ||
287922eb | 653 | static void blk_mq_timeout_work(struct work_struct *work) |
320ae51f | 654 | { |
287922eb CH |
655 | struct request_queue *q = |
656 | container_of(work, struct request_queue, timeout_work); | |
81481eb4 CH |
657 | struct blk_mq_timeout_data data = { |
658 | .next = 0, | |
659 | .next_set = 0, | |
660 | }; | |
81481eb4 | 661 | int i; |
320ae51f | 662 | |
71f79fb3 GKB |
663 | /* A deadlock might occur if a request is stuck requiring a |
664 | * timeout at the same time a queue freeze is waiting | |
665 | * completion, since the timeout code would not be able to | |
666 | * acquire the queue reference here. | |
667 | * | |
668 | * That's why we don't use blk_queue_enter here; instead, we use | |
669 | * percpu_ref_tryget directly, because we need to be able to | |
670 | * obtain a reference even in the short window between the queue | |
671 | * starting to freeze, by dropping the first reference in | |
672 | * blk_mq_freeze_queue_start, and the moment the last request is | |
673 | * consumed, marked by the instant q_usage_counter reaches | |
674 | * zero. | |
675 | */ | |
676 | if (!percpu_ref_tryget(&q->q_usage_counter)) | |
287922eb CH |
677 | return; |
678 | ||
0bf6cd5b | 679 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &data); |
320ae51f | 680 | |
81481eb4 CH |
681 | if (data.next_set) { |
682 | data.next = blk_rq_timeout(round_jiffies_up(data.next)); | |
683 | mod_timer(&q->timeout, data.next); | |
0d2602ca | 684 | } else { |
0bf6cd5b CH |
685 | struct blk_mq_hw_ctx *hctx; |
686 | ||
f054b56c ML |
687 | queue_for_each_hw_ctx(q, hctx, i) { |
688 | /* the hctx may be unmapped, so check it here */ | |
689 | if (blk_mq_hw_queue_mapped(hctx)) | |
690 | blk_mq_tag_idle(hctx); | |
691 | } | |
0d2602ca | 692 | } |
287922eb | 693 | blk_queue_exit(q); |
320ae51f JA |
694 | } |
695 | ||
696 | /* | |
697 | * Reverse check our software queue for entries that we could potentially | |
698 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
699 | * too much time checking for merges. | |
700 | */ | |
701 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
702 | struct blk_mq_ctx *ctx, struct bio *bio) | |
703 | { | |
704 | struct request *rq; | |
705 | int checked = 8; | |
706 | ||
707 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
708 | int el_ret; | |
709 | ||
710 | if (!checked--) | |
711 | break; | |
712 | ||
713 | if (!blk_rq_merge_ok(rq, bio)) | |
714 | continue; | |
715 | ||
716 | el_ret = blk_try_merge(rq, bio); | |
717 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
718 | if (bio_attempt_back_merge(q, rq, bio)) { | |
719 | ctx->rq_merged++; | |
720 | return true; | |
721 | } | |
722 | break; | |
723 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
724 | if (bio_attempt_front_merge(q, rq, bio)) { | |
725 | ctx->rq_merged++; | |
726 | return true; | |
727 | } | |
728 | break; | |
729 | } | |
730 | } | |
731 | ||
732 | return false; | |
733 | } | |
734 | ||
88459642 OS |
735 | struct flush_busy_ctx_data { |
736 | struct blk_mq_hw_ctx *hctx; | |
737 | struct list_head *list; | |
738 | }; | |
739 | ||
740 | static bool flush_busy_ctx(struct sbitmap *sb, unsigned int bitnr, void *data) | |
741 | { | |
742 | struct flush_busy_ctx_data *flush_data = data; | |
743 | struct blk_mq_hw_ctx *hctx = flush_data->hctx; | |
744 | struct blk_mq_ctx *ctx = hctx->ctxs[bitnr]; | |
745 | ||
746 | sbitmap_clear_bit(sb, bitnr); | |
747 | spin_lock(&ctx->lock); | |
748 | list_splice_tail_init(&ctx->rq_list, flush_data->list); | |
749 | spin_unlock(&ctx->lock); | |
750 | return true; | |
751 | } | |
752 | ||
1429d7c9 JA |
753 | /* |
754 | * Process software queues that have been marked busy, splicing them | |
755 | * to the for-dispatch | |
756 | */ | |
757 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
758 | { | |
88459642 OS |
759 | struct flush_busy_ctx_data data = { |
760 | .hctx = hctx, | |
761 | .list = list, | |
762 | }; | |
1429d7c9 | 763 | |
88459642 | 764 | sbitmap_for_each_set(&hctx->ctx_map, flush_busy_ctx, &data); |
1429d7c9 | 765 | } |
1429d7c9 | 766 | |
703fd1c0 JA |
767 | static inline unsigned int queued_to_index(unsigned int queued) |
768 | { | |
769 | if (!queued) | |
770 | return 0; | |
1429d7c9 | 771 | |
703fd1c0 | 772 | return min(BLK_MQ_MAX_DISPATCH_ORDER - 1, ilog2(queued) + 1); |
1429d7c9 JA |
773 | } |
774 | ||
320ae51f JA |
775 | /* |
776 | * Run this hardware queue, pulling any software queues mapped to it in. | |
777 | * Note that this function currently has various problems around ordering | |
778 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
779 | * items on the hctx->dispatch list. Ignore that for now. | |
780 | */ | |
781 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
782 | { | |
783 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
784 | struct request *rq; |
785 | LIST_HEAD(rq_list); | |
74c45052 JA |
786 | LIST_HEAD(driver_list); |
787 | struct list_head *dptr; | |
1429d7c9 | 788 | int queued; |
320ae51f | 789 | |
5d12f905 | 790 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
791 | return; |
792 | ||
0e87e58b JA |
793 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask) && |
794 | cpu_online(hctx->next_cpu)); | |
795 | ||
320ae51f JA |
796 | hctx->run++; |
797 | ||
798 | /* | |
799 | * Touch any software queue that has pending entries. | |
800 | */ | |
1429d7c9 | 801 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
802 | |
803 | /* | |
804 | * If we have previous entries on our dispatch list, grab them | |
805 | * and stuff them at the front for more fair dispatch. | |
806 | */ | |
807 | if (!list_empty_careful(&hctx->dispatch)) { | |
808 | spin_lock(&hctx->lock); | |
809 | if (!list_empty(&hctx->dispatch)) | |
810 | list_splice_init(&hctx->dispatch, &rq_list); | |
811 | spin_unlock(&hctx->lock); | |
812 | } | |
813 | ||
74c45052 JA |
814 | /* |
815 | * Start off with dptr being NULL, so we start the first request | |
816 | * immediately, even if we have more pending. | |
817 | */ | |
818 | dptr = NULL; | |
819 | ||
320ae51f JA |
820 | /* |
821 | * Now process all the entries, sending them to the driver. | |
822 | */ | |
1429d7c9 | 823 | queued = 0; |
320ae51f | 824 | while (!list_empty(&rq_list)) { |
74c45052 | 825 | struct blk_mq_queue_data bd; |
320ae51f JA |
826 | int ret; |
827 | ||
828 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
829 | list_del_init(&rq->queuelist); | |
320ae51f | 830 | |
74c45052 JA |
831 | bd.rq = rq; |
832 | bd.list = dptr; | |
833 | bd.last = list_empty(&rq_list); | |
834 | ||
835 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
320ae51f JA |
836 | switch (ret) { |
837 | case BLK_MQ_RQ_QUEUE_OK: | |
838 | queued++; | |
52b9c330 | 839 | break; |
320ae51f | 840 | case BLK_MQ_RQ_QUEUE_BUSY: |
320ae51f | 841 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 842 | __blk_mq_requeue_request(rq); |
320ae51f JA |
843 | break; |
844 | default: | |
845 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 846 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 847 | rq->errors = -EIO; |
c8a446ad | 848 | blk_mq_end_request(rq, rq->errors); |
320ae51f JA |
849 | break; |
850 | } | |
851 | ||
852 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
853 | break; | |
74c45052 JA |
854 | |
855 | /* | |
856 | * We've done the first request. If we have more than 1 | |
857 | * left in the list, set dptr to defer issue. | |
858 | */ | |
859 | if (!dptr && rq_list.next != rq_list.prev) | |
860 | dptr = &driver_list; | |
320ae51f JA |
861 | } |
862 | ||
703fd1c0 | 863 | hctx->dispatched[queued_to_index(queued)]++; |
320ae51f JA |
864 | |
865 | /* | |
866 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
867 | * that is where we will continue on next queue run. | |
868 | */ | |
869 | if (!list_empty(&rq_list)) { | |
870 | spin_lock(&hctx->lock); | |
871 | list_splice(&rq_list, &hctx->dispatch); | |
872 | spin_unlock(&hctx->lock); | |
9ba52e58 SL |
873 | /* |
874 | * the queue is expected stopped with BLK_MQ_RQ_QUEUE_BUSY, but | |
875 | * it's possible the queue is stopped and restarted again | |
876 | * before this. Queue restart will dispatch requests. And since | |
877 | * requests in rq_list aren't added into hctx->dispatch yet, | |
878 | * the requests in rq_list might get lost. | |
879 | * | |
880 | * blk_mq_run_hw_queue() already checks the STOPPED bit | |
881 | **/ | |
882 | blk_mq_run_hw_queue(hctx, true); | |
320ae51f JA |
883 | } |
884 | } | |
885 | ||
506e931f JA |
886 | /* |
887 | * It'd be great if the workqueue API had a way to pass | |
888 | * in a mask and had some smarts for more clever placement. | |
889 | * For now we just round-robin here, switching for every | |
890 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
891 | */ | |
892 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
893 | { | |
b657d7e6 CH |
894 | if (hctx->queue->nr_hw_queues == 1) |
895 | return WORK_CPU_UNBOUND; | |
506e931f JA |
896 | |
897 | if (--hctx->next_cpu_batch <= 0) { | |
b657d7e6 | 898 | int cpu = hctx->next_cpu, next_cpu; |
506e931f JA |
899 | |
900 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
901 | if (next_cpu >= nr_cpu_ids) | |
902 | next_cpu = cpumask_first(hctx->cpumask); | |
903 | ||
904 | hctx->next_cpu = next_cpu; | |
905 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
b657d7e6 CH |
906 | |
907 | return cpu; | |
506e931f JA |
908 | } |
909 | ||
b657d7e6 | 910 | return hctx->next_cpu; |
506e931f JA |
911 | } |
912 | ||
320ae51f JA |
913 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
914 | { | |
19c66e59 ML |
915 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state) || |
916 | !blk_mq_hw_queue_mapped(hctx))) | |
320ae51f JA |
917 | return; |
918 | ||
1b792f2f | 919 | if (!async && !(hctx->flags & BLK_MQ_F_BLOCKING)) { |
2a90d4aa PB |
920 | int cpu = get_cpu(); |
921 | if (cpumask_test_cpu(cpu, hctx->cpumask)) { | |
398205b8 | 922 | __blk_mq_run_hw_queue(hctx); |
2a90d4aa | 923 | put_cpu(); |
398205b8 PB |
924 | return; |
925 | } | |
e4043dcf | 926 | |
2a90d4aa | 927 | put_cpu(); |
e4043dcf | 928 | } |
398205b8 | 929 | |
27489a3c | 930 | kblockd_schedule_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work); |
320ae51f JA |
931 | } |
932 | ||
b94ec296 | 933 | void blk_mq_run_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
934 | { |
935 | struct blk_mq_hw_ctx *hctx; | |
936 | int i; | |
937 | ||
938 | queue_for_each_hw_ctx(q, hctx, i) { | |
939 | if ((!blk_mq_hctx_has_pending(hctx) && | |
940 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 941 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
942 | continue; |
943 | ||
b94ec296 | 944 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
945 | } |
946 | } | |
b94ec296 | 947 | EXPORT_SYMBOL(blk_mq_run_hw_queues); |
320ae51f JA |
948 | |
949 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
950 | { | |
27489a3c | 951 | cancel_work(&hctx->run_work); |
70f4db63 | 952 | cancel_delayed_work(&hctx->delay_work); |
320ae51f JA |
953 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
954 | } | |
955 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
956 | ||
280d45f6 CH |
957 | void blk_mq_stop_hw_queues(struct request_queue *q) |
958 | { | |
959 | struct blk_mq_hw_ctx *hctx; | |
960 | int i; | |
961 | ||
962 | queue_for_each_hw_ctx(q, hctx, i) | |
963 | blk_mq_stop_hw_queue(hctx); | |
964 | } | |
965 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
966 | ||
320ae51f JA |
967 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
968 | { | |
969 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 970 | |
0ffbce80 | 971 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
972 | } |
973 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
974 | ||
2f268556 CH |
975 | void blk_mq_start_hw_queues(struct request_queue *q) |
976 | { | |
977 | struct blk_mq_hw_ctx *hctx; | |
978 | int i; | |
979 | ||
980 | queue_for_each_hw_ctx(q, hctx, i) | |
981 | blk_mq_start_hw_queue(hctx); | |
982 | } | |
983 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
984 | ||
1b4a3258 | 985 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
986 | { |
987 | struct blk_mq_hw_ctx *hctx; | |
988 | int i; | |
989 | ||
990 | queue_for_each_hw_ctx(q, hctx, i) { | |
991 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
992 | continue; | |
993 | ||
994 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
1b4a3258 | 995 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
996 | } |
997 | } | |
998 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
999 | ||
70f4db63 | 1000 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
1001 | { |
1002 | struct blk_mq_hw_ctx *hctx; | |
1003 | ||
27489a3c | 1004 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work); |
e4043dcf | 1005 | |
320ae51f JA |
1006 | __blk_mq_run_hw_queue(hctx); |
1007 | } | |
1008 | ||
70f4db63 CH |
1009 | static void blk_mq_delay_work_fn(struct work_struct *work) |
1010 | { | |
1011 | struct blk_mq_hw_ctx *hctx; | |
1012 | ||
1013 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
1014 | ||
1015 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
1016 | __blk_mq_run_hw_queue(hctx); | |
1017 | } | |
1018 | ||
1019 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
1020 | { | |
19c66e59 ML |
1021 | if (unlikely(!blk_mq_hw_queue_mapped(hctx))) |
1022 | return; | |
70f4db63 | 1023 | |
b657d7e6 CH |
1024 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
1025 | &hctx->delay_work, msecs_to_jiffies(msecs)); | |
70f4db63 CH |
1026 | } |
1027 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
1028 | ||
cfd0c552 | 1029 | static inline void __blk_mq_insert_req_list(struct blk_mq_hw_ctx *hctx, |
cfd0c552 ML |
1030 | struct request *rq, |
1031 | bool at_head) | |
320ae51f | 1032 | { |
e57690fe JA |
1033 | struct blk_mq_ctx *ctx = rq->mq_ctx; |
1034 | ||
01b983c9 JA |
1035 | trace_block_rq_insert(hctx->queue, rq); |
1036 | ||
72a0a36e CH |
1037 | if (at_head) |
1038 | list_add(&rq->queuelist, &ctx->rq_list); | |
1039 | else | |
1040 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
cfd0c552 | 1041 | } |
4bb659b1 | 1042 | |
cfd0c552 ML |
1043 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
1044 | struct request *rq, bool at_head) | |
1045 | { | |
1046 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
1047 | ||
e57690fe | 1048 | __blk_mq_insert_req_list(hctx, rq, at_head); |
320ae51f | 1049 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
1050 | } |
1051 | ||
eeabc850 | 1052 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
e57690fe | 1053 | bool async) |
320ae51f | 1054 | { |
e57690fe | 1055 | struct blk_mq_ctx *ctx = rq->mq_ctx; |
eeabc850 | 1056 | struct request_queue *q = rq->q; |
7d7e0f90 | 1057 | struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu); |
320ae51f | 1058 | |
a57a178a CH |
1059 | spin_lock(&ctx->lock); |
1060 | __blk_mq_insert_request(hctx, rq, at_head); | |
1061 | spin_unlock(&ctx->lock); | |
320ae51f | 1062 | |
320ae51f JA |
1063 | if (run_queue) |
1064 | blk_mq_run_hw_queue(hctx, async); | |
1065 | } | |
1066 | ||
1067 | static void blk_mq_insert_requests(struct request_queue *q, | |
1068 | struct blk_mq_ctx *ctx, | |
1069 | struct list_head *list, | |
1070 | int depth, | |
1071 | bool from_schedule) | |
1072 | ||
1073 | { | |
7d7e0f90 | 1074 | struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu); |
320ae51f JA |
1075 | |
1076 | trace_block_unplug(q, depth, !from_schedule); | |
1077 | ||
320ae51f JA |
1078 | /* |
1079 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
1080 | * offline now | |
1081 | */ | |
1082 | spin_lock(&ctx->lock); | |
1083 | while (!list_empty(list)) { | |
1084 | struct request *rq; | |
1085 | ||
1086 | rq = list_first_entry(list, struct request, queuelist); | |
e57690fe | 1087 | BUG_ON(rq->mq_ctx != ctx); |
320ae51f | 1088 | list_del_init(&rq->queuelist); |
e57690fe | 1089 | __blk_mq_insert_req_list(hctx, rq, false); |
320ae51f | 1090 | } |
cfd0c552 | 1091 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
1092 | spin_unlock(&ctx->lock); |
1093 | ||
320ae51f JA |
1094 | blk_mq_run_hw_queue(hctx, from_schedule); |
1095 | } | |
1096 | ||
1097 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1098 | { | |
1099 | struct request *rqa = container_of(a, struct request, queuelist); | |
1100 | struct request *rqb = container_of(b, struct request, queuelist); | |
1101 | ||
1102 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1103 | (rqa->mq_ctx == rqb->mq_ctx && | |
1104 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1105 | } | |
1106 | ||
1107 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1108 | { | |
1109 | struct blk_mq_ctx *this_ctx; | |
1110 | struct request_queue *this_q; | |
1111 | struct request *rq; | |
1112 | LIST_HEAD(list); | |
1113 | LIST_HEAD(ctx_list); | |
1114 | unsigned int depth; | |
1115 | ||
1116 | list_splice_init(&plug->mq_list, &list); | |
1117 | ||
1118 | list_sort(NULL, &list, plug_ctx_cmp); | |
1119 | ||
1120 | this_q = NULL; | |
1121 | this_ctx = NULL; | |
1122 | depth = 0; | |
1123 | ||
1124 | while (!list_empty(&list)) { | |
1125 | rq = list_entry_rq(list.next); | |
1126 | list_del_init(&rq->queuelist); | |
1127 | BUG_ON(!rq->q); | |
1128 | if (rq->mq_ctx != this_ctx) { | |
1129 | if (this_ctx) { | |
1130 | blk_mq_insert_requests(this_q, this_ctx, | |
1131 | &ctx_list, depth, | |
1132 | from_schedule); | |
1133 | } | |
1134 | ||
1135 | this_ctx = rq->mq_ctx; | |
1136 | this_q = rq->q; | |
1137 | depth = 0; | |
1138 | } | |
1139 | ||
1140 | depth++; | |
1141 | list_add_tail(&rq->queuelist, &ctx_list); | |
1142 | } | |
1143 | ||
1144 | /* | |
1145 | * If 'this_ctx' is set, we know we have entries to complete | |
1146 | * on 'ctx_list'. Do those. | |
1147 | */ | |
1148 | if (this_ctx) { | |
1149 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1150 | from_schedule); | |
1151 | } | |
1152 | } | |
1153 | ||
1154 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1155 | { | |
1156 | init_request_from_bio(rq, bio); | |
4b570521 | 1157 | |
a21f2a3e | 1158 | blk_account_io_start(rq, 1); |
320ae51f JA |
1159 | } |
1160 | ||
274a5843 JA |
1161 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1162 | { | |
1163 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1164 | !blk_queue_nomerges(hctx->queue); | |
1165 | } | |
1166 | ||
07068d5b JA |
1167 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1168 | struct blk_mq_ctx *ctx, | |
1169 | struct request *rq, struct bio *bio) | |
320ae51f | 1170 | { |
e18378a6 | 1171 | if (!hctx_allow_merges(hctx) || !bio_mergeable(bio)) { |
07068d5b JA |
1172 | blk_mq_bio_to_request(rq, bio); |
1173 | spin_lock(&ctx->lock); | |
1174 | insert_rq: | |
1175 | __blk_mq_insert_request(hctx, rq, false); | |
1176 | spin_unlock(&ctx->lock); | |
1177 | return false; | |
1178 | } else { | |
274a5843 JA |
1179 | struct request_queue *q = hctx->queue; |
1180 | ||
07068d5b JA |
1181 | spin_lock(&ctx->lock); |
1182 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1183 | blk_mq_bio_to_request(rq, bio); | |
1184 | goto insert_rq; | |
1185 | } | |
320ae51f | 1186 | |
07068d5b JA |
1187 | spin_unlock(&ctx->lock); |
1188 | __blk_mq_free_request(hctx, ctx, rq); | |
1189 | return true; | |
14ec77f3 | 1190 | } |
07068d5b | 1191 | } |
14ec77f3 | 1192 | |
07068d5b JA |
1193 | struct blk_map_ctx { |
1194 | struct blk_mq_hw_ctx *hctx; | |
1195 | struct blk_mq_ctx *ctx; | |
1196 | }; | |
1197 | ||
1198 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1199 | struct bio *bio, | |
1200 | struct blk_map_ctx *data) | |
1201 | { | |
1202 | struct blk_mq_hw_ctx *hctx; | |
1203 | struct blk_mq_ctx *ctx; | |
1204 | struct request *rq; | |
cc6e3b10 MC |
1205 | int op = bio_data_dir(bio); |
1206 | int op_flags = 0; | |
cb96a42c | 1207 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1208 | |
3ef28e83 | 1209 | blk_queue_enter_live(q); |
320ae51f | 1210 | ctx = blk_mq_get_ctx(q); |
7d7e0f90 | 1211 | hctx = blk_mq_map_queue(q, ctx->cpu); |
320ae51f | 1212 | |
1eff9d32 | 1213 | if (rw_is_sync(bio_op(bio), bio->bi_opf)) |
cc6e3b10 | 1214 | op_flags |= REQ_SYNC; |
07068d5b | 1215 | |
cc6e3b10 | 1216 | trace_block_getrq(q, bio, op); |
63581af3 | 1217 | blk_mq_set_alloc_data(&alloc_data, q, 0, ctx, hctx); |
cc6e3b10 | 1218 | rq = __blk_mq_alloc_request(&alloc_data, op, op_flags); |
320ae51f JA |
1219 | |
1220 | hctx->queued++; | |
07068d5b JA |
1221 | data->hctx = hctx; |
1222 | data->ctx = ctx; | |
1223 | return rq; | |
1224 | } | |
1225 | ||
7b371636 | 1226 | static int blk_mq_direct_issue_request(struct request *rq, blk_qc_t *cookie) |
f984df1f SL |
1227 | { |
1228 | int ret; | |
1229 | struct request_queue *q = rq->q; | |
7d7e0f90 | 1230 | struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, rq->mq_ctx->cpu); |
f984df1f SL |
1231 | struct blk_mq_queue_data bd = { |
1232 | .rq = rq, | |
1233 | .list = NULL, | |
1234 | .last = 1 | |
1235 | }; | |
7b371636 | 1236 | blk_qc_t new_cookie = blk_tag_to_qc_t(rq->tag, hctx->queue_num); |
f984df1f SL |
1237 | |
1238 | /* | |
1239 | * For OK queue, we are done. For error, kill it. Any other | |
1240 | * error (busy), just add it to our list as we previously | |
1241 | * would have done | |
1242 | */ | |
1243 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
7b371636 JA |
1244 | if (ret == BLK_MQ_RQ_QUEUE_OK) { |
1245 | *cookie = new_cookie; | |
f984df1f | 1246 | return 0; |
7b371636 | 1247 | } |
f984df1f | 1248 | |
7b371636 JA |
1249 | __blk_mq_requeue_request(rq); |
1250 | ||
1251 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1252 | *cookie = BLK_QC_T_NONE; | |
1253 | rq->errors = -EIO; | |
1254 | blk_mq_end_request(rq, rq->errors); | |
1255 | return 0; | |
f984df1f | 1256 | } |
7b371636 JA |
1257 | |
1258 | return -1; | |
f984df1f SL |
1259 | } |
1260 | ||
07068d5b JA |
1261 | /* |
1262 | * Multiple hardware queue variant. This will not use per-process plugs, | |
1263 | * but will attempt to bypass the hctx queueing if we can go straight to | |
1264 | * hardware for SYNC IO. | |
1265 | */ | |
dece1635 | 1266 | static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) |
07068d5b | 1267 | { |
1eff9d32 JA |
1268 | const int is_sync = rw_is_sync(bio_op(bio), bio->bi_opf); |
1269 | const int is_flush_fua = bio->bi_opf & (REQ_PREFLUSH | REQ_FUA); | |
07068d5b JA |
1270 | struct blk_map_ctx data; |
1271 | struct request *rq; | |
f984df1f SL |
1272 | unsigned int request_count = 0; |
1273 | struct blk_plug *plug; | |
5b3f341f | 1274 | struct request *same_queue_rq = NULL; |
7b371636 | 1275 | blk_qc_t cookie; |
07068d5b JA |
1276 | |
1277 | blk_queue_bounce(q, &bio); | |
1278 | ||
1279 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1280 | bio_io_error(bio); |
dece1635 | 1281 | return BLK_QC_T_NONE; |
07068d5b JA |
1282 | } |
1283 | ||
54efd50b KO |
1284 | blk_queue_split(q, &bio, q->bio_split); |
1285 | ||
87c279e6 OS |
1286 | if (!is_flush_fua && !blk_queue_nomerges(q) && |
1287 | blk_attempt_plug_merge(q, bio, &request_count, &same_queue_rq)) | |
1288 | return BLK_QC_T_NONE; | |
f984df1f | 1289 | |
07068d5b JA |
1290 | rq = blk_mq_map_request(q, bio, &data); |
1291 | if (unlikely(!rq)) | |
dece1635 | 1292 | return BLK_QC_T_NONE; |
07068d5b | 1293 | |
7b371636 | 1294 | cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num); |
07068d5b JA |
1295 | |
1296 | if (unlikely(is_flush_fua)) { | |
1297 | blk_mq_bio_to_request(rq, bio); | |
1298 | blk_insert_flush(rq); | |
1299 | goto run_queue; | |
1300 | } | |
1301 | ||
f984df1f | 1302 | plug = current->plug; |
e167dfb5 JA |
1303 | /* |
1304 | * If the driver supports defer issued based on 'last', then | |
1305 | * queue it up like normal since we can potentially save some | |
1306 | * CPU this way. | |
1307 | */ | |
f984df1f SL |
1308 | if (((plug && !blk_queue_nomerges(q)) || is_sync) && |
1309 | !(data.hctx->flags & BLK_MQ_F_DEFER_ISSUE)) { | |
1310 | struct request *old_rq = NULL; | |
07068d5b JA |
1311 | |
1312 | blk_mq_bio_to_request(rq, bio); | |
07068d5b JA |
1313 | |
1314 | /* | |
b094f89c | 1315 | * We do limited pluging. If the bio can be merged, do that. |
f984df1f SL |
1316 | * Otherwise the existing request in the plug list will be |
1317 | * issued. So the plug list will have one request at most | |
07068d5b | 1318 | */ |
f984df1f | 1319 | if (plug) { |
5b3f341f SL |
1320 | /* |
1321 | * The plug list might get flushed before this. If that | |
b094f89c JA |
1322 | * happens, same_queue_rq is invalid and plug list is |
1323 | * empty | |
1324 | */ | |
5b3f341f SL |
1325 | if (same_queue_rq && !list_empty(&plug->mq_list)) { |
1326 | old_rq = same_queue_rq; | |
f984df1f | 1327 | list_del_init(&old_rq->queuelist); |
07068d5b | 1328 | } |
f984df1f SL |
1329 | list_add_tail(&rq->queuelist, &plug->mq_list); |
1330 | } else /* is_sync */ | |
1331 | old_rq = rq; | |
1332 | blk_mq_put_ctx(data.ctx); | |
1333 | if (!old_rq) | |
7b371636 JA |
1334 | goto done; |
1335 | if (!blk_mq_direct_issue_request(old_rq, &cookie)) | |
1336 | goto done; | |
f984df1f | 1337 | blk_mq_insert_request(old_rq, false, true, true); |
7b371636 | 1338 | goto done; |
07068d5b JA |
1339 | } |
1340 | ||
1341 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { | |
1342 | /* | |
1343 | * For a SYNC request, send it to the hardware immediately. For | |
1344 | * an ASYNC request, just ensure that we run it later on. The | |
1345 | * latter allows for merging opportunities and more efficient | |
1346 | * dispatching. | |
1347 | */ | |
1348 | run_queue: | |
1349 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
1350 | } | |
07068d5b | 1351 | blk_mq_put_ctx(data.ctx); |
7b371636 JA |
1352 | done: |
1353 | return cookie; | |
07068d5b JA |
1354 | } |
1355 | ||
1356 | /* | |
1357 | * Single hardware queue variant. This will attempt to use any per-process | |
1358 | * plug for merging and IO deferral. | |
1359 | */ | |
dece1635 | 1360 | static blk_qc_t blk_sq_make_request(struct request_queue *q, struct bio *bio) |
07068d5b | 1361 | { |
1eff9d32 JA |
1362 | const int is_sync = rw_is_sync(bio_op(bio), bio->bi_opf); |
1363 | const int is_flush_fua = bio->bi_opf & (REQ_PREFLUSH | REQ_FUA); | |
e6c4438b JM |
1364 | struct blk_plug *plug; |
1365 | unsigned int request_count = 0; | |
07068d5b JA |
1366 | struct blk_map_ctx data; |
1367 | struct request *rq; | |
7b371636 | 1368 | blk_qc_t cookie; |
07068d5b | 1369 | |
07068d5b JA |
1370 | blk_queue_bounce(q, &bio); |
1371 | ||
1372 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1373 | bio_io_error(bio); |
dece1635 | 1374 | return BLK_QC_T_NONE; |
07068d5b JA |
1375 | } |
1376 | ||
54efd50b KO |
1377 | blk_queue_split(q, &bio, q->bio_split); |
1378 | ||
87c279e6 OS |
1379 | if (!is_flush_fua && !blk_queue_nomerges(q)) { |
1380 | if (blk_attempt_plug_merge(q, bio, &request_count, NULL)) | |
1381 | return BLK_QC_T_NONE; | |
1382 | } else | |
1383 | request_count = blk_plug_queued_count(q); | |
07068d5b JA |
1384 | |
1385 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec | 1386 | if (unlikely(!rq)) |
dece1635 | 1387 | return BLK_QC_T_NONE; |
320ae51f | 1388 | |
7b371636 | 1389 | cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num); |
320ae51f JA |
1390 | |
1391 | if (unlikely(is_flush_fua)) { | |
1392 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1393 | blk_insert_flush(rq); |
1394 | goto run_queue; | |
1395 | } | |
1396 | ||
1397 | /* | |
1398 | * A task plug currently exists. Since this is completely lockless, | |
1399 | * utilize that to temporarily store requests until the task is | |
1400 | * either done or scheduled away. | |
1401 | */ | |
e6c4438b JM |
1402 | plug = current->plug; |
1403 | if (plug) { | |
1404 | blk_mq_bio_to_request(rq, bio); | |
676d0607 | 1405 | if (!request_count) |
e6c4438b | 1406 | trace_block_plug(q); |
b094f89c JA |
1407 | |
1408 | blk_mq_put_ctx(data.ctx); | |
1409 | ||
1410 | if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
e6c4438b JM |
1411 | blk_flush_plug_list(plug, false); |
1412 | trace_block_plug(q); | |
320ae51f | 1413 | } |
b094f89c | 1414 | |
e6c4438b | 1415 | list_add_tail(&rq->queuelist, &plug->mq_list); |
7b371636 | 1416 | return cookie; |
320ae51f JA |
1417 | } |
1418 | ||
07068d5b JA |
1419 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1420 | /* | |
1421 | * For a SYNC request, send it to the hardware immediately. For | |
1422 | * an ASYNC request, just ensure that we run it later on. The | |
1423 | * latter allows for merging opportunities and more efficient | |
1424 | * dispatching. | |
1425 | */ | |
1426 | run_queue: | |
1427 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1428 | } |
1429 | ||
07068d5b | 1430 | blk_mq_put_ctx(data.ctx); |
7b371636 | 1431 | return cookie; |
320ae51f JA |
1432 | } |
1433 | ||
24d2f903 CH |
1434 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1435 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1436 | { |
e9b267d9 | 1437 | struct page *page; |
320ae51f | 1438 | |
24d2f903 | 1439 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1440 | int i; |
320ae51f | 1441 | |
24d2f903 CH |
1442 | for (i = 0; i < tags->nr_tags; i++) { |
1443 | if (!tags->rqs[i]) | |
e9b267d9 | 1444 | continue; |
24d2f903 CH |
1445 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1446 | hctx_idx, i); | |
a5164405 | 1447 | tags->rqs[i] = NULL; |
e9b267d9 | 1448 | } |
320ae51f | 1449 | } |
320ae51f | 1450 | |
24d2f903 CH |
1451 | while (!list_empty(&tags->page_list)) { |
1452 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1453 | list_del_init(&page->lru); |
f75782e4 CM |
1454 | /* |
1455 | * Remove kmemleak object previously allocated in | |
1456 | * blk_mq_init_rq_map(). | |
1457 | */ | |
1458 | kmemleak_free(page_address(page)); | |
320ae51f JA |
1459 | __free_pages(page, page->private); |
1460 | } | |
1461 | ||
24d2f903 | 1462 | kfree(tags->rqs); |
320ae51f | 1463 | |
24d2f903 | 1464 | blk_mq_free_tags(tags); |
320ae51f JA |
1465 | } |
1466 | ||
1467 | static size_t order_to_size(unsigned int order) | |
1468 | { | |
4ca08500 | 1469 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1470 | } |
1471 | ||
24d2f903 CH |
1472 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1473 | unsigned int hctx_idx) | |
320ae51f | 1474 | { |
24d2f903 | 1475 | struct blk_mq_tags *tags; |
320ae51f JA |
1476 | unsigned int i, j, entries_per_page, max_order = 4; |
1477 | size_t rq_size, left; | |
1478 | ||
24d2f903 | 1479 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
24391c0d SL |
1480 | set->numa_node, |
1481 | BLK_MQ_FLAG_TO_ALLOC_POLICY(set->flags)); | |
24d2f903 CH |
1482 | if (!tags) |
1483 | return NULL; | |
320ae51f | 1484 | |
24d2f903 CH |
1485 | INIT_LIST_HEAD(&tags->page_list); |
1486 | ||
a5164405 JA |
1487 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1488 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1489 | set->numa_node); | |
24d2f903 CH |
1490 | if (!tags->rqs) { |
1491 | blk_mq_free_tags(tags); | |
1492 | return NULL; | |
1493 | } | |
320ae51f JA |
1494 | |
1495 | /* | |
1496 | * rq_size is the size of the request plus driver payload, rounded | |
1497 | * to the cacheline size | |
1498 | */ | |
24d2f903 | 1499 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1500 | cache_line_size()); |
24d2f903 | 1501 | left = rq_size * set->queue_depth; |
320ae51f | 1502 | |
24d2f903 | 1503 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1504 | int this_order = max_order; |
1505 | struct page *page; | |
1506 | int to_do; | |
1507 | void *p; | |
1508 | ||
b3a834b1 | 1509 | while (this_order && left < order_to_size(this_order - 1)) |
320ae51f JA |
1510 | this_order--; |
1511 | ||
1512 | do { | |
a5164405 | 1513 | page = alloc_pages_node(set->numa_node, |
ac211175 | 1514 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO, |
a5164405 | 1515 | this_order); |
320ae51f JA |
1516 | if (page) |
1517 | break; | |
1518 | if (!this_order--) | |
1519 | break; | |
1520 | if (order_to_size(this_order) < rq_size) | |
1521 | break; | |
1522 | } while (1); | |
1523 | ||
1524 | if (!page) | |
24d2f903 | 1525 | goto fail; |
320ae51f JA |
1526 | |
1527 | page->private = this_order; | |
24d2f903 | 1528 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1529 | |
1530 | p = page_address(page); | |
f75782e4 CM |
1531 | /* |
1532 | * Allow kmemleak to scan these pages as they contain pointers | |
1533 | * to additional allocations like via ops->init_request(). | |
1534 | */ | |
1535 | kmemleak_alloc(p, order_to_size(this_order), 1, GFP_KERNEL); | |
320ae51f | 1536 | entries_per_page = order_to_size(this_order) / rq_size; |
24d2f903 | 1537 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1538 | left -= to_do * rq_size; |
1539 | for (j = 0; j < to_do; j++) { | |
24d2f903 CH |
1540 | tags->rqs[i] = p; |
1541 | if (set->ops->init_request) { | |
1542 | if (set->ops->init_request(set->driver_data, | |
1543 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1544 | set->numa_node)) { |
1545 | tags->rqs[i] = NULL; | |
24d2f903 | 1546 | goto fail; |
a5164405 | 1547 | } |
e9b267d9 CH |
1548 | } |
1549 | ||
320ae51f JA |
1550 | p += rq_size; |
1551 | i++; | |
1552 | } | |
1553 | } | |
24d2f903 | 1554 | return tags; |
320ae51f | 1555 | |
24d2f903 | 1556 | fail: |
24d2f903 CH |
1557 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1558 | return NULL; | |
320ae51f JA |
1559 | } |
1560 | ||
e57690fe JA |
1561 | /* |
1562 | * 'cpu' is going away. splice any existing rq_list entries from this | |
1563 | * software queue to the hw queue dispatch list, and ensure that it | |
1564 | * gets run. | |
1565 | */ | |
9467f859 | 1566 | static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) |
484b4061 | 1567 | { |
9467f859 | 1568 | struct blk_mq_hw_ctx *hctx; |
484b4061 JA |
1569 | struct blk_mq_ctx *ctx; |
1570 | LIST_HEAD(tmp); | |
1571 | ||
9467f859 | 1572 | hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead); |
e57690fe | 1573 | ctx = __blk_mq_get_ctx(hctx->queue, cpu); |
484b4061 JA |
1574 | |
1575 | spin_lock(&ctx->lock); | |
1576 | if (!list_empty(&ctx->rq_list)) { | |
1577 | list_splice_init(&ctx->rq_list, &tmp); | |
1578 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1579 | } | |
1580 | spin_unlock(&ctx->lock); | |
1581 | ||
1582 | if (list_empty(&tmp)) | |
9467f859 | 1583 | return 0; |
484b4061 | 1584 | |
e57690fe JA |
1585 | spin_lock(&hctx->lock); |
1586 | list_splice_tail_init(&tmp, &hctx->dispatch); | |
1587 | spin_unlock(&hctx->lock); | |
484b4061 JA |
1588 | |
1589 | blk_mq_run_hw_queue(hctx, true); | |
9467f859 | 1590 | return 0; |
484b4061 JA |
1591 | } |
1592 | ||
9467f859 | 1593 | static void blk_mq_remove_cpuhp(struct blk_mq_hw_ctx *hctx) |
484b4061 | 1594 | { |
9467f859 TG |
1595 | cpuhp_state_remove_instance_nocalls(CPUHP_BLK_MQ_DEAD, |
1596 | &hctx->cpuhp_dead); | |
484b4061 JA |
1597 | } |
1598 | ||
c3b4afca | 1599 | /* hctx->ctxs will be freed in queue's release handler */ |
08e98fc6 ML |
1600 | static void blk_mq_exit_hctx(struct request_queue *q, |
1601 | struct blk_mq_tag_set *set, | |
1602 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
1603 | { | |
f70ced09 ML |
1604 | unsigned flush_start_tag = set->queue_depth; |
1605 | ||
08e98fc6 ML |
1606 | blk_mq_tag_idle(hctx); |
1607 | ||
f70ced09 ML |
1608 | if (set->ops->exit_request) |
1609 | set->ops->exit_request(set->driver_data, | |
1610 | hctx->fq->flush_rq, hctx_idx, | |
1611 | flush_start_tag + hctx_idx); | |
1612 | ||
08e98fc6 ML |
1613 | if (set->ops->exit_hctx) |
1614 | set->ops->exit_hctx(hctx, hctx_idx); | |
1615 | ||
9467f859 | 1616 | blk_mq_remove_cpuhp(hctx); |
f70ced09 | 1617 | blk_free_flush_queue(hctx->fq); |
88459642 | 1618 | sbitmap_free(&hctx->ctx_map); |
08e98fc6 ML |
1619 | } |
1620 | ||
624dbe47 ML |
1621 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1622 | struct blk_mq_tag_set *set, int nr_queue) | |
1623 | { | |
1624 | struct blk_mq_hw_ctx *hctx; | |
1625 | unsigned int i; | |
1626 | ||
1627 | queue_for_each_hw_ctx(q, hctx, i) { | |
1628 | if (i == nr_queue) | |
1629 | break; | |
08e98fc6 | 1630 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 1631 | } |
624dbe47 ML |
1632 | } |
1633 | ||
1634 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1635 | struct blk_mq_tag_set *set) | |
1636 | { | |
1637 | struct blk_mq_hw_ctx *hctx; | |
1638 | unsigned int i; | |
1639 | ||
e09aae7e | 1640 | queue_for_each_hw_ctx(q, hctx, i) |
624dbe47 | 1641 | free_cpumask_var(hctx->cpumask); |
624dbe47 ML |
1642 | } |
1643 | ||
08e98fc6 ML |
1644 | static int blk_mq_init_hctx(struct request_queue *q, |
1645 | struct blk_mq_tag_set *set, | |
1646 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 1647 | { |
08e98fc6 | 1648 | int node; |
f70ced09 | 1649 | unsigned flush_start_tag = set->queue_depth; |
08e98fc6 ML |
1650 | |
1651 | node = hctx->numa_node; | |
1652 | if (node == NUMA_NO_NODE) | |
1653 | node = hctx->numa_node = set->numa_node; | |
1654 | ||
27489a3c | 1655 | INIT_WORK(&hctx->run_work, blk_mq_run_work_fn); |
08e98fc6 ML |
1656 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); |
1657 | spin_lock_init(&hctx->lock); | |
1658 | INIT_LIST_HEAD(&hctx->dispatch); | |
1659 | hctx->queue = q; | |
1660 | hctx->queue_num = hctx_idx; | |
2404e607 | 1661 | hctx->flags = set->flags & ~BLK_MQ_F_TAG_SHARED; |
08e98fc6 | 1662 | |
9467f859 | 1663 | cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead); |
08e98fc6 ML |
1664 | |
1665 | hctx->tags = set->tags[hctx_idx]; | |
320ae51f JA |
1666 | |
1667 | /* | |
08e98fc6 ML |
1668 | * Allocate space for all possible cpus to avoid allocation at |
1669 | * runtime | |
320ae51f | 1670 | */ |
08e98fc6 ML |
1671 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), |
1672 | GFP_KERNEL, node); | |
1673 | if (!hctx->ctxs) | |
1674 | goto unregister_cpu_notifier; | |
320ae51f | 1675 | |
88459642 OS |
1676 | if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8), GFP_KERNEL, |
1677 | node)) | |
08e98fc6 | 1678 | goto free_ctxs; |
320ae51f | 1679 | |
08e98fc6 | 1680 | hctx->nr_ctx = 0; |
320ae51f | 1681 | |
08e98fc6 ML |
1682 | if (set->ops->init_hctx && |
1683 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
1684 | goto free_bitmap; | |
320ae51f | 1685 | |
f70ced09 ML |
1686 | hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); |
1687 | if (!hctx->fq) | |
1688 | goto exit_hctx; | |
320ae51f | 1689 | |
f70ced09 ML |
1690 | if (set->ops->init_request && |
1691 | set->ops->init_request(set->driver_data, | |
1692 | hctx->fq->flush_rq, hctx_idx, | |
1693 | flush_start_tag + hctx_idx, node)) | |
1694 | goto free_fq; | |
320ae51f | 1695 | |
08e98fc6 | 1696 | return 0; |
320ae51f | 1697 | |
f70ced09 ML |
1698 | free_fq: |
1699 | kfree(hctx->fq); | |
1700 | exit_hctx: | |
1701 | if (set->ops->exit_hctx) | |
1702 | set->ops->exit_hctx(hctx, hctx_idx); | |
08e98fc6 | 1703 | free_bitmap: |
88459642 | 1704 | sbitmap_free(&hctx->ctx_map); |
08e98fc6 ML |
1705 | free_ctxs: |
1706 | kfree(hctx->ctxs); | |
1707 | unregister_cpu_notifier: | |
9467f859 | 1708 | blk_mq_remove_cpuhp(hctx); |
08e98fc6 ML |
1709 | return -1; |
1710 | } | |
320ae51f | 1711 | |
320ae51f JA |
1712 | static void blk_mq_init_cpu_queues(struct request_queue *q, |
1713 | unsigned int nr_hw_queues) | |
1714 | { | |
1715 | unsigned int i; | |
1716 | ||
1717 | for_each_possible_cpu(i) { | |
1718 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1719 | struct blk_mq_hw_ctx *hctx; | |
1720 | ||
1721 | memset(__ctx, 0, sizeof(*__ctx)); | |
1722 | __ctx->cpu = i; | |
1723 | spin_lock_init(&__ctx->lock); | |
1724 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1725 | __ctx->queue = q; | |
1726 | ||
1727 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1728 | if (!cpu_online(i)) |
1729 | continue; | |
1730 | ||
7d7e0f90 | 1731 | hctx = blk_mq_map_queue(q, i); |
e4043dcf | 1732 | |
320ae51f JA |
1733 | /* |
1734 | * Set local node, IFF we have more than one hw queue. If | |
1735 | * not, we remain on the home node of the device | |
1736 | */ | |
1737 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
bffed457 | 1738 | hctx->numa_node = local_memory_node(cpu_to_node(i)); |
320ae51f JA |
1739 | } |
1740 | } | |
1741 | ||
5778322e AM |
1742 | static void blk_mq_map_swqueue(struct request_queue *q, |
1743 | const struct cpumask *online_mask) | |
320ae51f JA |
1744 | { |
1745 | unsigned int i; | |
1746 | struct blk_mq_hw_ctx *hctx; | |
1747 | struct blk_mq_ctx *ctx; | |
2a34c087 | 1748 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 1749 | |
60de074b AM |
1750 | /* |
1751 | * Avoid others reading imcomplete hctx->cpumask through sysfs | |
1752 | */ | |
1753 | mutex_lock(&q->sysfs_lock); | |
1754 | ||
320ae51f | 1755 | queue_for_each_hw_ctx(q, hctx, i) { |
e4043dcf | 1756 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1757 | hctx->nr_ctx = 0; |
1758 | } | |
1759 | ||
1760 | /* | |
1761 | * Map software to hardware queues | |
1762 | */ | |
897bb0c7 | 1763 | for_each_possible_cpu(i) { |
320ae51f | 1764 | /* If the cpu isn't online, the cpu is mapped to first hctx */ |
5778322e | 1765 | if (!cpumask_test_cpu(i, online_mask)) |
e4043dcf JA |
1766 | continue; |
1767 | ||
897bb0c7 | 1768 | ctx = per_cpu_ptr(q->queue_ctx, i); |
7d7e0f90 | 1769 | hctx = blk_mq_map_queue(q, i); |
868f2f0b | 1770 | |
e4043dcf | 1771 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1772 | ctx->index_hw = hctx->nr_ctx; |
1773 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1774 | } | |
506e931f | 1775 | |
60de074b AM |
1776 | mutex_unlock(&q->sysfs_lock); |
1777 | ||
506e931f | 1778 | queue_for_each_hw_ctx(q, hctx, i) { |
484b4061 | 1779 | /* |
a68aafa5 JA |
1780 | * If no software queues are mapped to this hardware queue, |
1781 | * disable it and free the request entries. | |
484b4061 JA |
1782 | */ |
1783 | if (!hctx->nr_ctx) { | |
484b4061 JA |
1784 | if (set->tags[i]) { |
1785 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1786 | set->tags[i] = NULL; | |
484b4061 | 1787 | } |
2a34c087 | 1788 | hctx->tags = NULL; |
484b4061 JA |
1789 | continue; |
1790 | } | |
1791 | ||
2a34c087 ML |
1792 | /* unmapped hw queue can be remapped after CPU topo changed */ |
1793 | if (!set->tags[i]) | |
1794 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1795 | hctx->tags = set->tags[i]; | |
1796 | WARN_ON(!hctx->tags); | |
1797 | ||
889fa31f CY |
1798 | /* |
1799 | * Set the map size to the number of mapped software queues. | |
1800 | * This is more accurate and more efficient than looping | |
1801 | * over all possibly mapped software queues. | |
1802 | */ | |
88459642 | 1803 | sbitmap_resize(&hctx->ctx_map, hctx->nr_ctx); |
889fa31f | 1804 | |
484b4061 JA |
1805 | /* |
1806 | * Initialize batch roundrobin counts | |
1807 | */ | |
506e931f JA |
1808 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1809 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1810 | } | |
320ae51f JA |
1811 | } |
1812 | ||
2404e607 | 1813 | static void queue_set_hctx_shared(struct request_queue *q, bool shared) |
0d2602ca JA |
1814 | { |
1815 | struct blk_mq_hw_ctx *hctx; | |
0d2602ca JA |
1816 | int i; |
1817 | ||
2404e607 JM |
1818 | queue_for_each_hw_ctx(q, hctx, i) { |
1819 | if (shared) | |
1820 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1821 | else | |
1822 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1823 | } | |
1824 | } | |
1825 | ||
1826 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set, bool shared) | |
1827 | { | |
1828 | struct request_queue *q; | |
0d2602ca JA |
1829 | |
1830 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1831 | blk_mq_freeze_queue(q); | |
2404e607 | 1832 | queue_set_hctx_shared(q, shared); |
0d2602ca JA |
1833 | blk_mq_unfreeze_queue(q); |
1834 | } | |
1835 | } | |
1836 | ||
1837 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1838 | { | |
1839 | struct blk_mq_tag_set *set = q->tag_set; | |
1840 | ||
0d2602ca JA |
1841 | mutex_lock(&set->tag_list_lock); |
1842 | list_del_init(&q->tag_set_list); | |
2404e607 JM |
1843 | if (list_is_singular(&set->tag_list)) { |
1844 | /* just transitioned to unshared */ | |
1845 | set->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1846 | /* update existing queue */ | |
1847 | blk_mq_update_tag_set_depth(set, false); | |
1848 | } | |
0d2602ca | 1849 | mutex_unlock(&set->tag_list_lock); |
0d2602ca JA |
1850 | } |
1851 | ||
1852 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1853 | struct request_queue *q) | |
1854 | { | |
1855 | q->tag_set = set; | |
1856 | ||
1857 | mutex_lock(&set->tag_list_lock); | |
2404e607 JM |
1858 | |
1859 | /* Check to see if we're transitioning to shared (from 1 to 2 queues). */ | |
1860 | if (!list_empty(&set->tag_list) && !(set->flags & BLK_MQ_F_TAG_SHARED)) { | |
1861 | set->flags |= BLK_MQ_F_TAG_SHARED; | |
1862 | /* update existing queue */ | |
1863 | blk_mq_update_tag_set_depth(set, true); | |
1864 | } | |
1865 | if (set->flags & BLK_MQ_F_TAG_SHARED) | |
1866 | queue_set_hctx_shared(q, true); | |
0d2602ca | 1867 | list_add_tail(&q->tag_set_list, &set->tag_list); |
2404e607 | 1868 | |
0d2602ca JA |
1869 | mutex_unlock(&set->tag_list_lock); |
1870 | } | |
1871 | ||
e09aae7e ML |
1872 | /* |
1873 | * It is the actual release handler for mq, but we do it from | |
1874 | * request queue's release handler for avoiding use-after-free | |
1875 | * and headache because q->mq_kobj shouldn't have been introduced, | |
1876 | * but we can't group ctx/kctx kobj without it. | |
1877 | */ | |
1878 | void blk_mq_release(struct request_queue *q) | |
1879 | { | |
1880 | struct blk_mq_hw_ctx *hctx; | |
1881 | unsigned int i; | |
1882 | ||
1883 | /* hctx kobj stays in hctx */ | |
c3b4afca ML |
1884 | queue_for_each_hw_ctx(q, hctx, i) { |
1885 | if (!hctx) | |
1886 | continue; | |
1887 | kfree(hctx->ctxs); | |
e09aae7e | 1888 | kfree(hctx); |
c3b4afca | 1889 | } |
e09aae7e | 1890 | |
a723bab3 AM |
1891 | q->mq_map = NULL; |
1892 | ||
e09aae7e ML |
1893 | kfree(q->queue_hw_ctx); |
1894 | ||
1895 | /* ctx kobj stays in queue_ctx */ | |
1896 | free_percpu(q->queue_ctx); | |
1897 | } | |
1898 | ||
24d2f903 | 1899 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
b62c21b7 MS |
1900 | { |
1901 | struct request_queue *uninit_q, *q; | |
1902 | ||
1903 | uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); | |
1904 | if (!uninit_q) | |
1905 | return ERR_PTR(-ENOMEM); | |
1906 | ||
1907 | q = blk_mq_init_allocated_queue(set, uninit_q); | |
1908 | if (IS_ERR(q)) | |
1909 | blk_cleanup_queue(uninit_q); | |
1910 | ||
1911 | return q; | |
1912 | } | |
1913 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1914 | ||
868f2f0b KB |
1915 | static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, |
1916 | struct request_queue *q) | |
320ae51f | 1917 | { |
868f2f0b KB |
1918 | int i, j; |
1919 | struct blk_mq_hw_ctx **hctxs = q->queue_hw_ctx; | |
f14bbe77 | 1920 | |
868f2f0b | 1921 | blk_mq_sysfs_unregister(q); |
24d2f903 | 1922 | for (i = 0; i < set->nr_hw_queues; i++) { |
868f2f0b | 1923 | int node; |
f14bbe77 | 1924 | |
868f2f0b KB |
1925 | if (hctxs[i]) |
1926 | continue; | |
1927 | ||
1928 | node = blk_mq_hw_queue_to_node(q->mq_map, i); | |
cdef54dd CH |
1929 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1930 | GFP_KERNEL, node); | |
320ae51f | 1931 | if (!hctxs[i]) |
868f2f0b | 1932 | break; |
320ae51f | 1933 | |
a86073e4 | 1934 | if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, |
868f2f0b KB |
1935 | node)) { |
1936 | kfree(hctxs[i]); | |
1937 | hctxs[i] = NULL; | |
1938 | break; | |
1939 | } | |
e4043dcf | 1940 | |
0d2602ca | 1941 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1942 | hctxs[i]->numa_node = node; |
320ae51f | 1943 | hctxs[i]->queue_num = i; |
868f2f0b KB |
1944 | |
1945 | if (blk_mq_init_hctx(q, set, hctxs[i], i)) { | |
1946 | free_cpumask_var(hctxs[i]->cpumask); | |
1947 | kfree(hctxs[i]); | |
1948 | hctxs[i] = NULL; | |
1949 | break; | |
1950 | } | |
1951 | blk_mq_hctx_kobj_init(hctxs[i]); | |
320ae51f | 1952 | } |
868f2f0b KB |
1953 | for (j = i; j < q->nr_hw_queues; j++) { |
1954 | struct blk_mq_hw_ctx *hctx = hctxs[j]; | |
1955 | ||
1956 | if (hctx) { | |
1957 | if (hctx->tags) { | |
1958 | blk_mq_free_rq_map(set, hctx->tags, j); | |
1959 | set->tags[j] = NULL; | |
1960 | } | |
1961 | blk_mq_exit_hctx(q, set, hctx, j); | |
1962 | free_cpumask_var(hctx->cpumask); | |
1963 | kobject_put(&hctx->kobj); | |
1964 | kfree(hctx->ctxs); | |
1965 | kfree(hctx); | |
1966 | hctxs[j] = NULL; | |
1967 | ||
1968 | } | |
1969 | } | |
1970 | q->nr_hw_queues = i; | |
1971 | blk_mq_sysfs_register(q); | |
1972 | } | |
1973 | ||
1974 | struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, | |
1975 | struct request_queue *q) | |
1976 | { | |
66841672 ML |
1977 | /* mark the queue as mq asap */ |
1978 | q->mq_ops = set->ops; | |
1979 | ||
868f2f0b KB |
1980 | q->queue_ctx = alloc_percpu(struct blk_mq_ctx); |
1981 | if (!q->queue_ctx) | |
c7de5726 | 1982 | goto err_exit; |
868f2f0b KB |
1983 | |
1984 | q->queue_hw_ctx = kzalloc_node(nr_cpu_ids * sizeof(*(q->queue_hw_ctx)), | |
1985 | GFP_KERNEL, set->numa_node); | |
1986 | if (!q->queue_hw_ctx) | |
1987 | goto err_percpu; | |
1988 | ||
bdd17e75 | 1989 | q->mq_map = set->mq_map; |
868f2f0b KB |
1990 | |
1991 | blk_mq_realloc_hw_ctxs(set, q); | |
1992 | if (!q->nr_hw_queues) | |
1993 | goto err_hctxs; | |
320ae51f | 1994 | |
287922eb | 1995 | INIT_WORK(&q->timeout_work, blk_mq_timeout_work); |
e56f698b | 1996 | blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); |
320ae51f JA |
1997 | |
1998 | q->nr_queues = nr_cpu_ids; | |
320ae51f | 1999 | |
94eddfbe | 2000 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 2001 | |
05f1dd53 JA |
2002 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
2003 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
2004 | ||
1be036e9 CH |
2005 | q->sg_reserved_size = INT_MAX; |
2006 | ||
2849450a | 2007 | INIT_DELAYED_WORK(&q->requeue_work, blk_mq_requeue_work); |
6fca6a61 CH |
2008 | INIT_LIST_HEAD(&q->requeue_list); |
2009 | spin_lock_init(&q->requeue_lock); | |
2010 | ||
07068d5b JA |
2011 | if (q->nr_hw_queues > 1) |
2012 | blk_queue_make_request(q, blk_mq_make_request); | |
2013 | else | |
2014 | blk_queue_make_request(q, blk_sq_make_request); | |
2015 | ||
eba71768 JA |
2016 | /* |
2017 | * Do this after blk_queue_make_request() overrides it... | |
2018 | */ | |
2019 | q->nr_requests = set->queue_depth; | |
2020 | ||
24d2f903 CH |
2021 | if (set->ops->complete) |
2022 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 2023 | |
24d2f903 | 2024 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 2025 | |
5778322e | 2026 | get_online_cpus(); |
320ae51f | 2027 | mutex_lock(&all_q_mutex); |
320ae51f | 2028 | |
4593fdbe | 2029 | list_add_tail(&q->all_q_node, &all_q_list); |
0d2602ca | 2030 | blk_mq_add_queue_tag_set(set, q); |
5778322e | 2031 | blk_mq_map_swqueue(q, cpu_online_mask); |
484b4061 | 2032 | |
4593fdbe | 2033 | mutex_unlock(&all_q_mutex); |
5778322e | 2034 | put_online_cpus(); |
4593fdbe | 2035 | |
320ae51f | 2036 | return q; |
18741986 | 2037 | |
320ae51f | 2038 | err_hctxs: |
868f2f0b | 2039 | kfree(q->queue_hw_ctx); |
320ae51f | 2040 | err_percpu: |
868f2f0b | 2041 | free_percpu(q->queue_ctx); |
c7de5726 ML |
2042 | err_exit: |
2043 | q->mq_ops = NULL; | |
320ae51f JA |
2044 | return ERR_PTR(-ENOMEM); |
2045 | } | |
b62c21b7 | 2046 | EXPORT_SYMBOL(blk_mq_init_allocated_queue); |
320ae51f JA |
2047 | |
2048 | void blk_mq_free_queue(struct request_queue *q) | |
2049 | { | |
624dbe47 | 2050 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 2051 | |
0e626368 AM |
2052 | mutex_lock(&all_q_mutex); |
2053 | list_del_init(&q->all_q_node); | |
2054 | mutex_unlock(&all_q_mutex); | |
2055 | ||
0d2602ca JA |
2056 | blk_mq_del_queue_tag_set(q); |
2057 | ||
624dbe47 ML |
2058 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
2059 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 2060 | } |
320ae51f JA |
2061 | |
2062 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
5778322e AM |
2063 | static void blk_mq_queue_reinit(struct request_queue *q, |
2064 | const struct cpumask *online_mask) | |
320ae51f | 2065 | { |
4ecd4fef | 2066 | WARN_ON_ONCE(!atomic_read(&q->mq_freeze_depth)); |
320ae51f | 2067 | |
67aec14c JA |
2068 | blk_mq_sysfs_unregister(q); |
2069 | ||
320ae51f JA |
2070 | /* |
2071 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
2072 | * we should change hctx numa_node according to new topology (this | |
2073 | * involves free and re-allocate memory, worthy doing?) | |
2074 | */ | |
2075 | ||
5778322e | 2076 | blk_mq_map_swqueue(q, online_mask); |
320ae51f | 2077 | |
67aec14c | 2078 | blk_mq_sysfs_register(q); |
320ae51f JA |
2079 | } |
2080 | ||
65d5291e SAS |
2081 | /* |
2082 | * New online cpumask which is going to be set in this hotplug event. | |
2083 | * Declare this cpumasks as global as cpu-hotplug operation is invoked | |
2084 | * one-by-one and dynamically allocating this could result in a failure. | |
2085 | */ | |
2086 | static struct cpumask cpuhp_online_new; | |
2087 | ||
2088 | static void blk_mq_queue_reinit_work(void) | |
320ae51f JA |
2089 | { |
2090 | struct request_queue *q; | |
320ae51f JA |
2091 | |
2092 | mutex_lock(&all_q_mutex); | |
f3af020b TH |
2093 | /* |
2094 | * We need to freeze and reinit all existing queues. Freezing | |
2095 | * involves synchronous wait for an RCU grace period and doing it | |
2096 | * one by one may take a long time. Start freezing all queues in | |
2097 | * one swoop and then wait for the completions so that freezing can | |
2098 | * take place in parallel. | |
2099 | */ | |
2100 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2101 | blk_mq_freeze_queue_start(q); | |
f054b56c | 2102 | list_for_each_entry(q, &all_q_list, all_q_node) { |
f3af020b TH |
2103 | blk_mq_freeze_queue_wait(q); |
2104 | ||
f054b56c ML |
2105 | /* |
2106 | * timeout handler can't touch hw queue during the | |
2107 | * reinitialization | |
2108 | */ | |
2109 | del_timer_sync(&q->timeout); | |
2110 | } | |
2111 | ||
320ae51f | 2112 | list_for_each_entry(q, &all_q_list, all_q_node) |
65d5291e | 2113 | blk_mq_queue_reinit(q, &cpuhp_online_new); |
f3af020b TH |
2114 | |
2115 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2116 | blk_mq_unfreeze_queue(q); | |
2117 | ||
320ae51f | 2118 | mutex_unlock(&all_q_mutex); |
65d5291e SAS |
2119 | } |
2120 | ||
2121 | static int blk_mq_queue_reinit_dead(unsigned int cpu) | |
2122 | { | |
97a32864 | 2123 | cpumask_copy(&cpuhp_online_new, cpu_online_mask); |
65d5291e SAS |
2124 | blk_mq_queue_reinit_work(); |
2125 | return 0; | |
2126 | } | |
2127 | ||
2128 | /* | |
2129 | * Before hotadded cpu starts handling requests, new mappings must be | |
2130 | * established. Otherwise, these requests in hw queue might never be | |
2131 | * dispatched. | |
2132 | * | |
2133 | * For example, there is a single hw queue (hctx) and two CPU queues (ctx0 | |
2134 | * for CPU0, and ctx1 for CPU1). | |
2135 | * | |
2136 | * Now CPU1 is just onlined and a request is inserted into ctx1->rq_list | |
2137 | * and set bit0 in pending bitmap as ctx1->index_hw is still zero. | |
2138 | * | |
2139 | * And then while running hw queue, flush_busy_ctxs() finds bit0 is set in | |
2140 | * pending bitmap and tries to retrieve requests in hctx->ctxs[0]->rq_list. | |
2141 | * But htx->ctxs[0] is a pointer to ctx0, so the request in ctx1->rq_list | |
2142 | * is ignored. | |
2143 | */ | |
2144 | static int blk_mq_queue_reinit_prepare(unsigned int cpu) | |
2145 | { | |
2146 | cpumask_copy(&cpuhp_online_new, cpu_online_mask); | |
2147 | cpumask_set_cpu(cpu, &cpuhp_online_new); | |
2148 | blk_mq_queue_reinit_work(); | |
2149 | return 0; | |
320ae51f JA |
2150 | } |
2151 | ||
a5164405 JA |
2152 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
2153 | { | |
2154 | int i; | |
2155 | ||
2156 | for (i = 0; i < set->nr_hw_queues; i++) { | |
2157 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
2158 | if (!set->tags[i]) | |
2159 | goto out_unwind; | |
2160 | } | |
2161 | ||
2162 | return 0; | |
2163 | ||
2164 | out_unwind: | |
2165 | while (--i >= 0) | |
2166 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2167 | ||
a5164405 JA |
2168 | return -ENOMEM; |
2169 | } | |
2170 | ||
2171 | /* | |
2172 | * Allocate the request maps associated with this tag_set. Note that this | |
2173 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
2174 | * will be updated to reflect the allocated depth. | |
2175 | */ | |
2176 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
2177 | { | |
2178 | unsigned int depth; | |
2179 | int err; | |
2180 | ||
2181 | depth = set->queue_depth; | |
2182 | do { | |
2183 | err = __blk_mq_alloc_rq_maps(set); | |
2184 | if (!err) | |
2185 | break; | |
2186 | ||
2187 | set->queue_depth >>= 1; | |
2188 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
2189 | err = -ENOMEM; | |
2190 | break; | |
2191 | } | |
2192 | } while (set->queue_depth); | |
2193 | ||
2194 | if (!set->queue_depth || err) { | |
2195 | pr_err("blk-mq: failed to allocate request map\n"); | |
2196 | return -ENOMEM; | |
2197 | } | |
2198 | ||
2199 | if (depth != set->queue_depth) | |
2200 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2201 | depth, set->queue_depth); | |
2202 | ||
2203 | return 0; | |
2204 | } | |
2205 | ||
a4391c64 JA |
2206 | /* |
2207 | * Alloc a tag set to be associated with one or more request queues. | |
2208 | * May fail with EINVAL for various error conditions. May adjust the | |
2209 | * requested depth down, if if it too large. In that case, the set | |
2210 | * value will be stored in set->queue_depth. | |
2211 | */ | |
24d2f903 CH |
2212 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2213 | { | |
da695ba2 CH |
2214 | int ret; |
2215 | ||
205fb5f5 BVA |
2216 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
2217 | ||
24d2f903 CH |
2218 | if (!set->nr_hw_queues) |
2219 | return -EINVAL; | |
a4391c64 | 2220 | if (!set->queue_depth) |
24d2f903 CH |
2221 | return -EINVAL; |
2222 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2223 | return -EINVAL; | |
2224 | ||
7d7e0f90 | 2225 | if (!set->ops->queue_rq) |
24d2f903 CH |
2226 | return -EINVAL; |
2227 | ||
a4391c64 JA |
2228 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2229 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2230 | BLK_MQ_MAX_DEPTH); | |
2231 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2232 | } | |
24d2f903 | 2233 | |
6637fadf SL |
2234 | /* |
2235 | * If a crashdump is active, then we are potentially in a very | |
2236 | * memory constrained environment. Limit us to 1 queue and | |
2237 | * 64 tags to prevent using too much memory. | |
2238 | */ | |
2239 | if (is_kdump_kernel()) { | |
2240 | set->nr_hw_queues = 1; | |
2241 | set->queue_depth = min(64U, set->queue_depth); | |
2242 | } | |
868f2f0b KB |
2243 | /* |
2244 | * There is no use for more h/w queues than cpus. | |
2245 | */ | |
2246 | if (set->nr_hw_queues > nr_cpu_ids) | |
2247 | set->nr_hw_queues = nr_cpu_ids; | |
6637fadf | 2248 | |
868f2f0b | 2249 | set->tags = kzalloc_node(nr_cpu_ids * sizeof(struct blk_mq_tags *), |
24d2f903 CH |
2250 | GFP_KERNEL, set->numa_node); |
2251 | if (!set->tags) | |
a5164405 | 2252 | return -ENOMEM; |
24d2f903 | 2253 | |
da695ba2 CH |
2254 | ret = -ENOMEM; |
2255 | set->mq_map = kzalloc_node(sizeof(*set->mq_map) * nr_cpu_ids, | |
2256 | GFP_KERNEL, set->numa_node); | |
bdd17e75 CH |
2257 | if (!set->mq_map) |
2258 | goto out_free_tags; | |
2259 | ||
da695ba2 CH |
2260 | if (set->ops->map_queues) |
2261 | ret = set->ops->map_queues(set); | |
2262 | else | |
2263 | ret = blk_mq_map_queues(set); | |
2264 | if (ret) | |
2265 | goto out_free_mq_map; | |
2266 | ||
2267 | ret = blk_mq_alloc_rq_maps(set); | |
2268 | if (ret) | |
bdd17e75 | 2269 | goto out_free_mq_map; |
24d2f903 | 2270 | |
0d2602ca JA |
2271 | mutex_init(&set->tag_list_lock); |
2272 | INIT_LIST_HEAD(&set->tag_list); | |
2273 | ||
24d2f903 | 2274 | return 0; |
bdd17e75 CH |
2275 | |
2276 | out_free_mq_map: | |
2277 | kfree(set->mq_map); | |
2278 | set->mq_map = NULL; | |
2279 | out_free_tags: | |
5676e7b6 RE |
2280 | kfree(set->tags); |
2281 | set->tags = NULL; | |
da695ba2 | 2282 | return ret; |
24d2f903 CH |
2283 | } |
2284 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2285 | ||
2286 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2287 | { | |
2288 | int i; | |
2289 | ||
868f2f0b | 2290 | for (i = 0; i < nr_cpu_ids; i++) { |
f42d79ab | 2291 | if (set->tags[i]) |
484b4061 JA |
2292 | blk_mq_free_rq_map(set, set->tags[i], i); |
2293 | } | |
2294 | ||
bdd17e75 CH |
2295 | kfree(set->mq_map); |
2296 | set->mq_map = NULL; | |
2297 | ||
981bd189 | 2298 | kfree(set->tags); |
5676e7b6 | 2299 | set->tags = NULL; |
24d2f903 CH |
2300 | } |
2301 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2302 | ||
e3a2b3f9 JA |
2303 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2304 | { | |
2305 | struct blk_mq_tag_set *set = q->tag_set; | |
2306 | struct blk_mq_hw_ctx *hctx; | |
2307 | int i, ret; | |
2308 | ||
2309 | if (!set || nr > set->queue_depth) | |
2310 | return -EINVAL; | |
2311 | ||
2312 | ret = 0; | |
2313 | queue_for_each_hw_ctx(q, hctx, i) { | |
e9137d4b KB |
2314 | if (!hctx->tags) |
2315 | continue; | |
e3a2b3f9 JA |
2316 | ret = blk_mq_tag_update_depth(hctx->tags, nr); |
2317 | if (ret) | |
2318 | break; | |
2319 | } | |
2320 | ||
2321 | if (!ret) | |
2322 | q->nr_requests = nr; | |
2323 | ||
2324 | return ret; | |
2325 | } | |
2326 | ||
868f2f0b KB |
2327 | void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues) |
2328 | { | |
2329 | struct request_queue *q; | |
2330 | ||
2331 | if (nr_hw_queues > nr_cpu_ids) | |
2332 | nr_hw_queues = nr_cpu_ids; | |
2333 | if (nr_hw_queues < 1 || nr_hw_queues == set->nr_hw_queues) | |
2334 | return; | |
2335 | ||
2336 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
2337 | blk_mq_freeze_queue(q); | |
2338 | ||
2339 | set->nr_hw_queues = nr_hw_queues; | |
2340 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
2341 | blk_mq_realloc_hw_ctxs(set, q); | |
2342 | ||
2343 | if (q->nr_hw_queues > 1) | |
2344 | blk_queue_make_request(q, blk_mq_make_request); | |
2345 | else | |
2346 | blk_queue_make_request(q, blk_sq_make_request); | |
2347 | ||
2348 | blk_mq_queue_reinit(q, cpu_online_mask); | |
2349 | } | |
2350 | ||
2351 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
2352 | blk_mq_unfreeze_queue(q); | |
2353 | } | |
2354 | EXPORT_SYMBOL_GPL(blk_mq_update_nr_hw_queues); | |
2355 | ||
676141e4 JA |
2356 | void blk_mq_disable_hotplug(void) |
2357 | { | |
2358 | mutex_lock(&all_q_mutex); | |
2359 | } | |
2360 | ||
2361 | void blk_mq_enable_hotplug(void) | |
2362 | { | |
2363 | mutex_unlock(&all_q_mutex); | |
2364 | } | |
2365 | ||
320ae51f JA |
2366 | static int __init blk_mq_init(void) |
2367 | { | |
9467f859 TG |
2368 | cpuhp_setup_state_multi(CPUHP_BLK_MQ_DEAD, "block/mq:dead", NULL, |
2369 | blk_mq_hctx_notify_dead); | |
320ae51f | 2370 | |
65d5291e SAS |
2371 | cpuhp_setup_state_nocalls(CPUHP_BLK_MQ_PREPARE, "block/mq:prepare", |
2372 | blk_mq_queue_reinit_prepare, | |
2373 | blk_mq_queue_reinit_dead); | |
320ae51f JA |
2374 | return 0; |
2375 | } | |
2376 | subsys_initcall(blk_mq_init); |