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> |
320ae51f JA |
25 | |
26 | #include <trace/events/block.h> | |
27 | ||
28 | #include <linux/blk-mq.h> | |
29 | #include "blk.h" | |
30 | #include "blk-mq.h" | |
31 | #include "blk-mq-tag.h" | |
32 | ||
33 | static DEFINE_MUTEX(all_q_mutex); | |
34 | static LIST_HEAD(all_q_list); | |
35 | ||
36 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx); | |
37 | ||
320ae51f JA |
38 | /* |
39 | * Check if any of the ctx's have pending work in this hardware queue | |
40 | */ | |
41 | static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx) | |
42 | { | |
43 | unsigned int i; | |
44 | ||
569fd0ce | 45 | for (i = 0; i < hctx->ctx_map.size; i++) |
1429d7c9 | 46 | if (hctx->ctx_map.map[i].word) |
320ae51f JA |
47 | return true; |
48 | ||
49 | return false; | |
50 | } | |
51 | ||
1429d7c9 JA |
52 | static inline struct blk_align_bitmap *get_bm(struct blk_mq_hw_ctx *hctx, |
53 | struct blk_mq_ctx *ctx) | |
54 | { | |
55 | return &hctx->ctx_map.map[ctx->index_hw / hctx->ctx_map.bits_per_word]; | |
56 | } | |
57 | ||
58 | #define CTX_TO_BIT(hctx, ctx) \ | |
59 | ((ctx)->index_hw & ((hctx)->ctx_map.bits_per_word - 1)) | |
60 | ||
320ae51f JA |
61 | /* |
62 | * Mark this ctx as having pending work in this hardware queue | |
63 | */ | |
64 | static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, | |
65 | struct blk_mq_ctx *ctx) | |
66 | { | |
1429d7c9 JA |
67 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); |
68 | ||
69 | if (!test_bit(CTX_TO_BIT(hctx, ctx), &bm->word)) | |
70 | set_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
71 | } | |
72 | ||
73 | static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, | |
74 | struct blk_mq_ctx *ctx) | |
75 | { | |
76 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); | |
77 | ||
78 | clear_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
320ae51f JA |
79 | } |
80 | ||
b4c6a028 | 81 | void blk_mq_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 82 | { |
4ecd4fef | 83 | int freeze_depth; |
cddd5d17 | 84 | |
4ecd4fef CH |
85 | freeze_depth = atomic_inc_return(&q->mq_freeze_depth); |
86 | if (freeze_depth == 1) { | |
3ef28e83 | 87 | percpu_ref_kill(&q->q_usage_counter); |
b94ec296 | 88 | blk_mq_run_hw_queues(q, false); |
cddd5d17 | 89 | } |
f3af020b | 90 | } |
b4c6a028 | 91 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start); |
f3af020b TH |
92 | |
93 | static void blk_mq_freeze_queue_wait(struct request_queue *q) | |
94 | { | |
3ef28e83 | 95 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter)); |
43a5e4e2 ML |
96 | } |
97 | ||
f3af020b TH |
98 | /* |
99 | * Guarantee no request is in use, so we can change any data structure of | |
100 | * the queue afterward. | |
101 | */ | |
3ef28e83 | 102 | void blk_freeze_queue(struct request_queue *q) |
f3af020b | 103 | { |
3ef28e83 DW |
104 | /* |
105 | * In the !blk_mq case we are only calling this to kill the | |
106 | * q_usage_counter, otherwise this increases the freeze depth | |
107 | * and waits for it to return to zero. For this reason there is | |
108 | * no blk_unfreeze_queue(), and blk_freeze_queue() is not | |
109 | * exported to drivers as the only user for unfreeze is blk_mq. | |
110 | */ | |
f3af020b TH |
111 | blk_mq_freeze_queue_start(q); |
112 | blk_mq_freeze_queue_wait(q); | |
113 | } | |
3ef28e83 DW |
114 | |
115 | void blk_mq_freeze_queue(struct request_queue *q) | |
116 | { | |
117 | /* | |
118 | * ...just an alias to keep freeze and unfreeze actions balanced | |
119 | * in the blk_mq_* namespace | |
120 | */ | |
121 | blk_freeze_queue(q); | |
122 | } | |
c761d96b | 123 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue); |
f3af020b | 124 | |
b4c6a028 | 125 | void blk_mq_unfreeze_queue(struct request_queue *q) |
320ae51f | 126 | { |
4ecd4fef | 127 | int freeze_depth; |
320ae51f | 128 | |
4ecd4fef CH |
129 | freeze_depth = atomic_dec_return(&q->mq_freeze_depth); |
130 | WARN_ON_ONCE(freeze_depth < 0); | |
131 | if (!freeze_depth) { | |
3ef28e83 | 132 | percpu_ref_reinit(&q->q_usage_counter); |
320ae51f | 133 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 134 | } |
320ae51f | 135 | } |
b4c6a028 | 136 | EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
320ae51f | 137 | |
aed3ea94 JA |
138 | void blk_mq_wake_waiters(struct request_queue *q) |
139 | { | |
140 | struct blk_mq_hw_ctx *hctx; | |
141 | unsigned int i; | |
142 | ||
143 | queue_for_each_hw_ctx(q, hctx, i) | |
144 | if (blk_mq_hw_queue_mapped(hctx)) | |
145 | blk_mq_tag_wakeup_all(hctx->tags, true); | |
3fd5940c KB |
146 | |
147 | /* | |
148 | * If we are called because the queue has now been marked as | |
149 | * dying, we need to ensure that processes currently waiting on | |
150 | * the queue are notified as well. | |
151 | */ | |
152 | wake_up_all(&q->mq_freeze_wq); | |
aed3ea94 JA |
153 | } |
154 | ||
320ae51f JA |
155 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) |
156 | { | |
157 | return blk_mq_has_free_tags(hctx->tags); | |
158 | } | |
159 | EXPORT_SYMBOL(blk_mq_can_queue); | |
160 | ||
94eddfbe JA |
161 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
162 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 163 | { |
94eddfbe JA |
164 | if (blk_queue_io_stat(q)) |
165 | rw_flags |= REQ_IO_STAT; | |
166 | ||
af76e555 CH |
167 | INIT_LIST_HEAD(&rq->queuelist); |
168 | /* csd/requeue_work/fifo_time is initialized before use */ | |
169 | rq->q = q; | |
320ae51f | 170 | rq->mq_ctx = ctx; |
0d2602ca | 171 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
172 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
173 | rq->cpu = -1; | |
af76e555 CH |
174 | INIT_HLIST_NODE(&rq->hash); |
175 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
176 | rq->rq_disk = NULL; |
177 | rq->part = NULL; | |
3ee32372 | 178 | rq->start_time = jiffies; |
af76e555 CH |
179 | #ifdef CONFIG_BLK_CGROUP |
180 | rq->rl = NULL; | |
0fec08b4 | 181 | set_start_time_ns(rq); |
af76e555 CH |
182 | rq->io_start_time_ns = 0; |
183 | #endif | |
184 | rq->nr_phys_segments = 0; | |
185 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
186 | rq->nr_integrity_segments = 0; | |
187 | #endif | |
af76e555 CH |
188 | rq->special = NULL; |
189 | /* tag was already set */ | |
190 | rq->errors = 0; | |
af76e555 | 191 | |
6f4a1626 TB |
192 | rq->cmd = rq->__cmd; |
193 | ||
af76e555 CH |
194 | rq->extra_len = 0; |
195 | rq->sense_len = 0; | |
196 | rq->resid_len = 0; | |
197 | rq->sense = NULL; | |
198 | ||
af76e555 | 199 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
200 | rq->timeout = 0; |
201 | ||
af76e555 CH |
202 | rq->end_io = NULL; |
203 | rq->end_io_data = NULL; | |
204 | rq->next_rq = NULL; | |
205 | ||
320ae51f JA |
206 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
207 | } | |
208 | ||
5dee8577 | 209 | static struct request * |
cb96a42c | 210 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) |
5dee8577 CH |
211 | { |
212 | struct request *rq; | |
213 | unsigned int tag; | |
214 | ||
cb96a42c | 215 | tag = blk_mq_get_tag(data); |
5dee8577 | 216 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 217 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 218 | |
cb96a42c | 219 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 220 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 221 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
222 | } |
223 | ||
224 | rq->tag = tag; | |
cb96a42c | 225 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); |
5dee8577 CH |
226 | return rq; |
227 | } | |
228 | ||
229 | return NULL; | |
230 | } | |
231 | ||
6f3b0e8b CH |
232 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, |
233 | unsigned int flags) | |
320ae51f | 234 | { |
d852564f CH |
235 | struct blk_mq_ctx *ctx; |
236 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 237 | struct request *rq; |
cb96a42c | 238 | struct blk_mq_alloc_data alloc_data; |
a492f075 | 239 | int ret; |
320ae51f | 240 | |
6f3b0e8b | 241 | ret = blk_queue_enter(q, flags & BLK_MQ_REQ_NOWAIT); |
a492f075 JL |
242 | if (ret) |
243 | return ERR_PTR(ret); | |
320ae51f | 244 | |
d852564f CH |
245 | ctx = blk_mq_get_ctx(q); |
246 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
6f3b0e8b | 247 | blk_mq_set_alloc_data(&alloc_data, q, flags, ctx, hctx); |
d852564f | 248 | |
cb96a42c | 249 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
6f3b0e8b | 250 | if (!rq && !(flags & BLK_MQ_REQ_NOWAIT)) { |
d852564f CH |
251 | __blk_mq_run_hw_queue(hctx); |
252 | blk_mq_put_ctx(ctx); | |
253 | ||
254 | ctx = blk_mq_get_ctx(q); | |
255 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
6f3b0e8b | 256 | blk_mq_set_alloc_data(&alloc_data, q, flags, ctx, hctx); |
cb96a42c ML |
257 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
258 | ctx = alloc_data.ctx; | |
d852564f CH |
259 | } |
260 | blk_mq_put_ctx(ctx); | |
c76541a9 | 261 | if (!rq) { |
3ef28e83 | 262 | blk_queue_exit(q); |
a492f075 | 263 | return ERR_PTR(-EWOULDBLOCK); |
c76541a9 | 264 | } |
320ae51f JA |
265 | return rq; |
266 | } | |
4bb659b1 | 267 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 268 | |
320ae51f JA |
269 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
270 | struct blk_mq_ctx *ctx, struct request *rq) | |
271 | { | |
272 | const int tag = rq->tag; | |
273 | struct request_queue *q = rq->q; | |
274 | ||
0d2602ca JA |
275 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
276 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 277 | rq->cmd_flags = 0; |
0d2602ca | 278 | |
af76e555 | 279 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 280 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
3ef28e83 | 281 | blk_queue_exit(q); |
320ae51f JA |
282 | } |
283 | ||
7c7f2f2b | 284 | void blk_mq_free_hctx_request(struct blk_mq_hw_ctx *hctx, struct request *rq) |
320ae51f JA |
285 | { |
286 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
320ae51f JA |
287 | |
288 | ctx->rq_completed[rq_is_sync(rq)]++; | |
320ae51f | 289 | __blk_mq_free_request(hctx, ctx, rq); |
7c7f2f2b JA |
290 | |
291 | } | |
292 | EXPORT_SYMBOL_GPL(blk_mq_free_hctx_request); | |
293 | ||
294 | void blk_mq_free_request(struct request *rq) | |
295 | { | |
296 | struct blk_mq_hw_ctx *hctx; | |
297 | struct request_queue *q = rq->q; | |
298 | ||
299 | hctx = q->mq_ops->map_queue(q, rq->mq_ctx->cpu); | |
300 | blk_mq_free_hctx_request(hctx, rq); | |
320ae51f | 301 | } |
1a3b595a | 302 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 303 | |
c8a446ad | 304 | inline void __blk_mq_end_request(struct request *rq, int error) |
320ae51f | 305 | { |
0d11e6ac ML |
306 | blk_account_io_done(rq); |
307 | ||
91b63639 | 308 | if (rq->end_io) { |
320ae51f | 309 | rq->end_io(rq, error); |
91b63639 CH |
310 | } else { |
311 | if (unlikely(blk_bidi_rq(rq))) | |
312 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 313 | blk_mq_free_request(rq); |
91b63639 | 314 | } |
320ae51f | 315 | } |
c8a446ad | 316 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 317 | |
c8a446ad | 318 | void blk_mq_end_request(struct request *rq, int error) |
63151a44 CH |
319 | { |
320 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
321 | BUG(); | |
c8a446ad | 322 | __blk_mq_end_request(rq, error); |
63151a44 | 323 | } |
c8a446ad | 324 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 325 | |
30a91cb4 | 326 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 327 | { |
3d6efbf6 | 328 | struct request *rq = data; |
320ae51f | 329 | |
30a91cb4 | 330 | rq->q->softirq_done_fn(rq); |
320ae51f | 331 | } |
320ae51f | 332 | |
ed851860 | 333 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
334 | { |
335 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 336 | bool shared = false; |
320ae51f JA |
337 | int cpu; |
338 | ||
38535201 | 339 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
340 | rq->q->softirq_done_fn(rq); |
341 | return; | |
342 | } | |
320ae51f JA |
343 | |
344 | cpu = get_cpu(); | |
38535201 CH |
345 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
346 | shared = cpus_share_cache(cpu, ctx->cpu); | |
347 | ||
348 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 349 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
350 | rq->csd.info = rq; |
351 | rq->csd.flags = 0; | |
c46fff2a | 352 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 353 | } else { |
30a91cb4 | 354 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 355 | } |
320ae51f JA |
356 | put_cpu(); |
357 | } | |
30a91cb4 | 358 | |
1fa8cc52 | 359 | static void __blk_mq_complete_request(struct request *rq) |
ed851860 JA |
360 | { |
361 | struct request_queue *q = rq->q; | |
362 | ||
363 | if (!q->softirq_done_fn) | |
c8a446ad | 364 | blk_mq_end_request(rq, rq->errors); |
ed851860 JA |
365 | else |
366 | blk_mq_ipi_complete_request(rq); | |
367 | } | |
368 | ||
30a91cb4 CH |
369 | /** |
370 | * blk_mq_complete_request - end I/O on a request | |
371 | * @rq: the request being processed | |
372 | * | |
373 | * Description: | |
374 | * Ends all I/O on a request. It does not handle partial completions. | |
375 | * The actual completion happens out-of-order, through a IPI handler. | |
376 | **/ | |
f4829a9b | 377 | void blk_mq_complete_request(struct request *rq, int error) |
30a91cb4 | 378 | { |
95f09684 JA |
379 | struct request_queue *q = rq->q; |
380 | ||
381 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 382 | return; |
f4829a9b CH |
383 | if (!blk_mark_rq_complete(rq)) { |
384 | rq->errors = error; | |
ed851860 | 385 | __blk_mq_complete_request(rq); |
f4829a9b | 386 | } |
30a91cb4 CH |
387 | } |
388 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 389 | |
973c0191 KB |
390 | int blk_mq_request_started(struct request *rq) |
391 | { | |
392 | return test_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
393 | } | |
394 | EXPORT_SYMBOL_GPL(blk_mq_request_started); | |
395 | ||
e2490073 | 396 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
397 | { |
398 | struct request_queue *q = rq->q; | |
399 | ||
400 | trace_block_rq_issue(q, rq); | |
401 | ||
742ee69b | 402 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
403 | if (unlikely(blk_bidi_rq(rq))) |
404 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 405 | |
2b8393b4 | 406 | blk_add_timer(rq); |
87ee7b11 | 407 | |
538b7534 JA |
408 | /* |
409 | * Ensure that ->deadline is visible before set the started | |
410 | * flag and clear the completed flag. | |
411 | */ | |
412 | smp_mb__before_atomic(); | |
413 | ||
87ee7b11 JA |
414 | /* |
415 | * Mark us as started and clear complete. Complete might have been | |
416 | * set if requeue raced with timeout, which then marked it as | |
417 | * complete. So be sure to clear complete again when we start | |
418 | * the request, otherwise we'll ignore the completion event. | |
419 | */ | |
4b570521 JA |
420 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
421 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
422 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
423 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
424 | |
425 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
426 | /* | |
427 | * Make sure space for the drain appears. We know we can do | |
428 | * this because max_hw_segments has been adjusted to be one | |
429 | * fewer than the device can handle. | |
430 | */ | |
431 | rq->nr_phys_segments++; | |
432 | } | |
320ae51f | 433 | } |
e2490073 | 434 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 435 | |
ed0791b2 | 436 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
437 | { |
438 | struct request_queue *q = rq->q; | |
439 | ||
440 | trace_block_rq_requeue(q, rq); | |
49f5baa5 | 441 | |
e2490073 CH |
442 | if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
443 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
444 | rq->nr_phys_segments--; | |
445 | } | |
320ae51f JA |
446 | } |
447 | ||
ed0791b2 CH |
448 | void blk_mq_requeue_request(struct request *rq) |
449 | { | |
ed0791b2 | 450 | __blk_mq_requeue_request(rq); |
ed0791b2 | 451 | |
ed0791b2 | 452 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 453 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
454 | } |
455 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
456 | ||
6fca6a61 CH |
457 | static void blk_mq_requeue_work(struct work_struct *work) |
458 | { | |
459 | struct request_queue *q = | |
460 | container_of(work, struct request_queue, requeue_work); | |
461 | LIST_HEAD(rq_list); | |
462 | struct request *rq, *next; | |
463 | unsigned long flags; | |
464 | ||
465 | spin_lock_irqsave(&q->requeue_lock, flags); | |
466 | list_splice_init(&q->requeue_list, &rq_list); | |
467 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
468 | ||
469 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
470 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
471 | continue; | |
472 | ||
473 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
474 | list_del_init(&rq->queuelist); | |
475 | blk_mq_insert_request(rq, true, false, false); | |
476 | } | |
477 | ||
478 | while (!list_empty(&rq_list)) { | |
479 | rq = list_entry(rq_list.next, struct request, queuelist); | |
480 | list_del_init(&rq->queuelist); | |
481 | blk_mq_insert_request(rq, false, false, false); | |
482 | } | |
483 | ||
8b957415 JA |
484 | /* |
485 | * Use the start variant of queue running here, so that running | |
486 | * the requeue work will kick stopped queues. | |
487 | */ | |
488 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
489 | } |
490 | ||
491 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
492 | { | |
493 | struct request_queue *q = rq->q; | |
494 | unsigned long flags; | |
495 | ||
496 | /* | |
497 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
498 | * request head insertation from the workqueue. | |
499 | */ | |
500 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
501 | ||
502 | spin_lock_irqsave(&q->requeue_lock, flags); | |
503 | if (at_head) { | |
504 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
505 | list_add(&rq->queuelist, &q->requeue_list); | |
506 | } else { | |
507 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
508 | } | |
509 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
510 | } | |
511 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
512 | ||
c68ed59f KB |
513 | void blk_mq_cancel_requeue_work(struct request_queue *q) |
514 | { | |
515 | cancel_work_sync(&q->requeue_work); | |
516 | } | |
517 | EXPORT_SYMBOL_GPL(blk_mq_cancel_requeue_work); | |
518 | ||
6fca6a61 CH |
519 | void blk_mq_kick_requeue_list(struct request_queue *q) |
520 | { | |
521 | kblockd_schedule_work(&q->requeue_work); | |
522 | } | |
523 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
524 | ||
1885b24d JA |
525 | void blk_mq_abort_requeue_list(struct request_queue *q) |
526 | { | |
527 | unsigned long flags; | |
528 | LIST_HEAD(rq_list); | |
529 | ||
530 | spin_lock_irqsave(&q->requeue_lock, flags); | |
531 | list_splice_init(&q->requeue_list, &rq_list); | |
532 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
533 | ||
534 | while (!list_empty(&rq_list)) { | |
535 | struct request *rq; | |
536 | ||
537 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
538 | list_del_init(&rq->queuelist); | |
539 | rq->errors = -EIO; | |
540 | blk_mq_end_request(rq, rq->errors); | |
541 | } | |
542 | } | |
543 | EXPORT_SYMBOL(blk_mq_abort_requeue_list); | |
544 | ||
0e62f51f JA |
545 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) |
546 | { | |
4ee86bab HR |
547 | if (tag < tags->nr_tags) |
548 | return tags->rqs[tag]; | |
549 | ||
550 | return NULL; | |
24d2f903 CH |
551 | } |
552 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
553 | ||
320ae51f | 554 | struct blk_mq_timeout_data { |
46f92d42 CH |
555 | unsigned long next; |
556 | unsigned int next_set; | |
320ae51f JA |
557 | }; |
558 | ||
90415837 | 559 | void blk_mq_rq_timed_out(struct request *req, bool reserved) |
320ae51f | 560 | { |
46f92d42 CH |
561 | struct blk_mq_ops *ops = req->q->mq_ops; |
562 | enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER; | |
87ee7b11 JA |
563 | |
564 | /* | |
565 | * We know that complete is set at this point. If STARTED isn't set | |
566 | * anymore, then the request isn't active and the "timeout" should | |
567 | * just be ignored. This can happen due to the bitflag ordering. | |
568 | * Timeout first checks if STARTED is set, and if it is, assumes | |
569 | * the request is active. But if we race with completion, then | |
570 | * we both flags will get cleared. So check here again, and ignore | |
571 | * a timeout event with a request that isn't active. | |
572 | */ | |
46f92d42 CH |
573 | if (!test_bit(REQ_ATOM_STARTED, &req->atomic_flags)) |
574 | return; | |
87ee7b11 | 575 | |
46f92d42 | 576 | if (ops->timeout) |
0152fb6b | 577 | ret = ops->timeout(req, reserved); |
46f92d42 CH |
578 | |
579 | switch (ret) { | |
580 | case BLK_EH_HANDLED: | |
581 | __blk_mq_complete_request(req); | |
582 | break; | |
583 | case BLK_EH_RESET_TIMER: | |
584 | blk_add_timer(req); | |
585 | blk_clear_rq_complete(req); | |
586 | break; | |
587 | case BLK_EH_NOT_HANDLED: | |
588 | break; | |
589 | default: | |
590 | printk(KERN_ERR "block: bad eh return: %d\n", ret); | |
591 | break; | |
592 | } | |
87ee7b11 | 593 | } |
5b3f25fc | 594 | |
81481eb4 CH |
595 | static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, |
596 | struct request *rq, void *priv, bool reserved) | |
597 | { | |
598 | struct blk_mq_timeout_data *data = priv; | |
87ee7b11 | 599 | |
eb130dbf KB |
600 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
601 | /* | |
602 | * If a request wasn't started before the queue was | |
603 | * marked dying, kill it here or it'll go unnoticed. | |
604 | */ | |
a59e0f57 KB |
605 | if (unlikely(blk_queue_dying(rq->q))) { |
606 | rq->errors = -EIO; | |
607 | blk_mq_end_request(rq, rq->errors); | |
608 | } | |
46f92d42 | 609 | return; |
eb130dbf | 610 | } |
87ee7b11 | 611 | |
46f92d42 CH |
612 | if (time_after_eq(jiffies, rq->deadline)) { |
613 | if (!blk_mark_rq_complete(rq)) | |
0152fb6b | 614 | blk_mq_rq_timed_out(rq, reserved); |
46f92d42 CH |
615 | } else if (!data->next_set || time_after(data->next, rq->deadline)) { |
616 | data->next = rq->deadline; | |
617 | data->next_set = 1; | |
618 | } | |
87ee7b11 JA |
619 | } |
620 | ||
287922eb | 621 | static void blk_mq_timeout_work(struct work_struct *work) |
320ae51f | 622 | { |
287922eb CH |
623 | struct request_queue *q = |
624 | container_of(work, struct request_queue, timeout_work); | |
81481eb4 CH |
625 | struct blk_mq_timeout_data data = { |
626 | .next = 0, | |
627 | .next_set = 0, | |
628 | }; | |
81481eb4 | 629 | int i; |
320ae51f | 630 | |
287922eb CH |
631 | if (blk_queue_enter(q, true)) |
632 | return; | |
633 | ||
0bf6cd5b | 634 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &data); |
320ae51f | 635 | |
81481eb4 CH |
636 | if (data.next_set) { |
637 | data.next = blk_rq_timeout(round_jiffies_up(data.next)); | |
638 | mod_timer(&q->timeout, data.next); | |
0d2602ca | 639 | } else { |
0bf6cd5b CH |
640 | struct blk_mq_hw_ctx *hctx; |
641 | ||
f054b56c ML |
642 | queue_for_each_hw_ctx(q, hctx, i) { |
643 | /* the hctx may be unmapped, so check it here */ | |
644 | if (blk_mq_hw_queue_mapped(hctx)) | |
645 | blk_mq_tag_idle(hctx); | |
646 | } | |
0d2602ca | 647 | } |
287922eb | 648 | blk_queue_exit(q); |
320ae51f JA |
649 | } |
650 | ||
651 | /* | |
652 | * Reverse check our software queue for entries that we could potentially | |
653 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
654 | * too much time checking for merges. | |
655 | */ | |
656 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
657 | struct blk_mq_ctx *ctx, struct bio *bio) | |
658 | { | |
659 | struct request *rq; | |
660 | int checked = 8; | |
661 | ||
662 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
663 | int el_ret; | |
664 | ||
665 | if (!checked--) | |
666 | break; | |
667 | ||
668 | if (!blk_rq_merge_ok(rq, bio)) | |
669 | continue; | |
670 | ||
671 | el_ret = blk_try_merge(rq, bio); | |
672 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
673 | if (bio_attempt_back_merge(q, rq, bio)) { | |
674 | ctx->rq_merged++; | |
675 | return true; | |
676 | } | |
677 | break; | |
678 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
679 | if (bio_attempt_front_merge(q, rq, bio)) { | |
680 | ctx->rq_merged++; | |
681 | return true; | |
682 | } | |
683 | break; | |
684 | } | |
685 | } | |
686 | ||
687 | return false; | |
688 | } | |
689 | ||
1429d7c9 JA |
690 | /* |
691 | * Process software queues that have been marked busy, splicing them | |
692 | * to the for-dispatch | |
693 | */ | |
694 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
695 | { | |
696 | struct blk_mq_ctx *ctx; | |
697 | int i; | |
698 | ||
569fd0ce | 699 | for (i = 0; i < hctx->ctx_map.size; i++) { |
1429d7c9 JA |
700 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; |
701 | unsigned int off, bit; | |
702 | ||
703 | if (!bm->word) | |
704 | continue; | |
705 | ||
706 | bit = 0; | |
707 | off = i * hctx->ctx_map.bits_per_word; | |
708 | do { | |
709 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
710 | if (bit >= bm->depth) | |
711 | break; | |
712 | ||
713 | ctx = hctx->ctxs[bit + off]; | |
714 | clear_bit(bit, &bm->word); | |
715 | spin_lock(&ctx->lock); | |
716 | list_splice_tail_init(&ctx->rq_list, list); | |
717 | spin_unlock(&ctx->lock); | |
718 | ||
719 | bit++; | |
720 | } while (1); | |
721 | } | |
722 | } | |
723 | ||
320ae51f JA |
724 | /* |
725 | * Run this hardware queue, pulling any software queues mapped to it in. | |
726 | * Note that this function currently has various problems around ordering | |
727 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
728 | * items on the hctx->dispatch list. Ignore that for now. | |
729 | */ | |
730 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
731 | { | |
732 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
733 | struct request *rq; |
734 | LIST_HEAD(rq_list); | |
74c45052 JA |
735 | LIST_HEAD(driver_list); |
736 | struct list_head *dptr; | |
1429d7c9 | 737 | int queued; |
320ae51f | 738 | |
fd1270d5 | 739 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 740 | |
5d12f905 | 741 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
742 | return; |
743 | ||
744 | hctx->run++; | |
745 | ||
746 | /* | |
747 | * Touch any software queue that has pending entries. | |
748 | */ | |
1429d7c9 | 749 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
750 | |
751 | /* | |
752 | * If we have previous entries on our dispatch list, grab them | |
753 | * and stuff them at the front for more fair dispatch. | |
754 | */ | |
755 | if (!list_empty_careful(&hctx->dispatch)) { | |
756 | spin_lock(&hctx->lock); | |
757 | if (!list_empty(&hctx->dispatch)) | |
758 | list_splice_init(&hctx->dispatch, &rq_list); | |
759 | spin_unlock(&hctx->lock); | |
760 | } | |
761 | ||
74c45052 JA |
762 | /* |
763 | * Start off with dptr being NULL, so we start the first request | |
764 | * immediately, even if we have more pending. | |
765 | */ | |
766 | dptr = NULL; | |
767 | ||
320ae51f JA |
768 | /* |
769 | * Now process all the entries, sending them to the driver. | |
770 | */ | |
1429d7c9 | 771 | queued = 0; |
320ae51f | 772 | while (!list_empty(&rq_list)) { |
74c45052 | 773 | struct blk_mq_queue_data bd; |
320ae51f JA |
774 | int ret; |
775 | ||
776 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
777 | list_del_init(&rq->queuelist); | |
320ae51f | 778 | |
74c45052 JA |
779 | bd.rq = rq; |
780 | bd.list = dptr; | |
781 | bd.last = list_empty(&rq_list); | |
782 | ||
783 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
320ae51f JA |
784 | switch (ret) { |
785 | case BLK_MQ_RQ_QUEUE_OK: | |
786 | queued++; | |
787 | continue; | |
788 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 789 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 790 | __blk_mq_requeue_request(rq); |
320ae51f JA |
791 | break; |
792 | default: | |
793 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 794 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 795 | rq->errors = -EIO; |
c8a446ad | 796 | blk_mq_end_request(rq, rq->errors); |
320ae51f JA |
797 | break; |
798 | } | |
799 | ||
800 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
801 | break; | |
74c45052 JA |
802 | |
803 | /* | |
804 | * We've done the first request. If we have more than 1 | |
805 | * left in the list, set dptr to defer issue. | |
806 | */ | |
807 | if (!dptr && rq_list.next != rq_list.prev) | |
808 | dptr = &driver_list; | |
320ae51f JA |
809 | } |
810 | ||
811 | if (!queued) | |
812 | hctx->dispatched[0]++; | |
813 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
814 | hctx->dispatched[ilog2(queued) + 1]++; | |
815 | ||
816 | /* | |
817 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
818 | * that is where we will continue on next queue run. | |
819 | */ | |
820 | if (!list_empty(&rq_list)) { | |
821 | spin_lock(&hctx->lock); | |
822 | list_splice(&rq_list, &hctx->dispatch); | |
823 | spin_unlock(&hctx->lock); | |
9ba52e58 SL |
824 | /* |
825 | * the queue is expected stopped with BLK_MQ_RQ_QUEUE_BUSY, but | |
826 | * it's possible the queue is stopped and restarted again | |
827 | * before this. Queue restart will dispatch requests. And since | |
828 | * requests in rq_list aren't added into hctx->dispatch yet, | |
829 | * the requests in rq_list might get lost. | |
830 | * | |
831 | * blk_mq_run_hw_queue() already checks the STOPPED bit | |
832 | **/ | |
833 | blk_mq_run_hw_queue(hctx, true); | |
320ae51f JA |
834 | } |
835 | } | |
836 | ||
506e931f JA |
837 | /* |
838 | * It'd be great if the workqueue API had a way to pass | |
839 | * in a mask and had some smarts for more clever placement. | |
840 | * For now we just round-robin here, switching for every | |
841 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
842 | */ | |
843 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
844 | { | |
b657d7e6 CH |
845 | if (hctx->queue->nr_hw_queues == 1) |
846 | return WORK_CPU_UNBOUND; | |
506e931f JA |
847 | |
848 | if (--hctx->next_cpu_batch <= 0) { | |
b657d7e6 | 849 | int cpu = hctx->next_cpu, next_cpu; |
506e931f JA |
850 | |
851 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
852 | if (next_cpu >= nr_cpu_ids) | |
853 | next_cpu = cpumask_first(hctx->cpumask); | |
854 | ||
855 | hctx->next_cpu = next_cpu; | |
856 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
b657d7e6 CH |
857 | |
858 | return cpu; | |
506e931f JA |
859 | } |
860 | ||
b657d7e6 | 861 | return hctx->next_cpu; |
506e931f JA |
862 | } |
863 | ||
320ae51f JA |
864 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
865 | { | |
19c66e59 ML |
866 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state) || |
867 | !blk_mq_hw_queue_mapped(hctx))) | |
320ae51f JA |
868 | return; |
869 | ||
398205b8 | 870 | if (!async) { |
2a90d4aa PB |
871 | int cpu = get_cpu(); |
872 | if (cpumask_test_cpu(cpu, hctx->cpumask)) { | |
398205b8 | 873 | __blk_mq_run_hw_queue(hctx); |
2a90d4aa | 874 | put_cpu(); |
398205b8 PB |
875 | return; |
876 | } | |
e4043dcf | 877 | |
2a90d4aa | 878 | put_cpu(); |
e4043dcf | 879 | } |
398205b8 | 880 | |
b657d7e6 CH |
881 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
882 | &hctx->run_work, 0); | |
320ae51f JA |
883 | } |
884 | ||
b94ec296 | 885 | void blk_mq_run_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
886 | { |
887 | struct blk_mq_hw_ctx *hctx; | |
888 | int i; | |
889 | ||
890 | queue_for_each_hw_ctx(q, hctx, i) { | |
891 | if ((!blk_mq_hctx_has_pending(hctx) && | |
892 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 893 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
894 | continue; |
895 | ||
b94ec296 | 896 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
897 | } |
898 | } | |
b94ec296 | 899 | EXPORT_SYMBOL(blk_mq_run_hw_queues); |
320ae51f JA |
900 | |
901 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
902 | { | |
70f4db63 CH |
903 | cancel_delayed_work(&hctx->run_work); |
904 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
905 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
906 | } | |
907 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
908 | ||
280d45f6 CH |
909 | void blk_mq_stop_hw_queues(struct request_queue *q) |
910 | { | |
911 | struct blk_mq_hw_ctx *hctx; | |
912 | int i; | |
913 | ||
914 | queue_for_each_hw_ctx(q, hctx, i) | |
915 | blk_mq_stop_hw_queue(hctx); | |
916 | } | |
917 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
918 | ||
320ae51f JA |
919 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
920 | { | |
921 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 922 | |
0ffbce80 | 923 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
924 | } |
925 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
926 | ||
2f268556 CH |
927 | void blk_mq_start_hw_queues(struct request_queue *q) |
928 | { | |
929 | struct blk_mq_hw_ctx *hctx; | |
930 | int i; | |
931 | ||
932 | queue_for_each_hw_ctx(q, hctx, i) | |
933 | blk_mq_start_hw_queue(hctx); | |
934 | } | |
935 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
936 | ||
1b4a3258 | 937 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
938 | { |
939 | struct blk_mq_hw_ctx *hctx; | |
940 | int i; | |
941 | ||
942 | queue_for_each_hw_ctx(q, hctx, i) { | |
943 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
944 | continue; | |
945 | ||
946 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
1b4a3258 | 947 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
948 | } |
949 | } | |
950 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
951 | ||
70f4db63 | 952 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
953 | { |
954 | struct blk_mq_hw_ctx *hctx; | |
955 | ||
70f4db63 | 956 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 957 | |
320ae51f JA |
958 | __blk_mq_run_hw_queue(hctx); |
959 | } | |
960 | ||
70f4db63 CH |
961 | static void blk_mq_delay_work_fn(struct work_struct *work) |
962 | { | |
963 | struct blk_mq_hw_ctx *hctx; | |
964 | ||
965 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
966 | ||
967 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
968 | __blk_mq_run_hw_queue(hctx); | |
969 | } | |
970 | ||
971 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
972 | { | |
19c66e59 ML |
973 | if (unlikely(!blk_mq_hw_queue_mapped(hctx))) |
974 | return; | |
70f4db63 | 975 | |
b657d7e6 CH |
976 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
977 | &hctx->delay_work, msecs_to_jiffies(msecs)); | |
70f4db63 CH |
978 | } |
979 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
980 | ||
cfd0c552 ML |
981 | static inline void __blk_mq_insert_req_list(struct blk_mq_hw_ctx *hctx, |
982 | struct blk_mq_ctx *ctx, | |
983 | struct request *rq, | |
984 | bool at_head) | |
320ae51f | 985 | { |
01b983c9 JA |
986 | trace_block_rq_insert(hctx->queue, rq); |
987 | ||
72a0a36e CH |
988 | if (at_head) |
989 | list_add(&rq->queuelist, &ctx->rq_list); | |
990 | else | |
991 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
cfd0c552 | 992 | } |
4bb659b1 | 993 | |
cfd0c552 ML |
994 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
995 | struct request *rq, bool at_head) | |
996 | { | |
997 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
998 | ||
999 | __blk_mq_insert_req_list(hctx, ctx, rq, at_head); | |
320ae51f | 1000 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
1001 | } |
1002 | ||
eeabc850 CH |
1003 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
1004 | bool async) | |
320ae51f | 1005 | { |
eeabc850 | 1006 | struct request_queue *q = rq->q; |
320ae51f | 1007 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
1008 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
1009 | ||
1010 | current_ctx = blk_mq_get_ctx(q); | |
1011 | if (!cpu_online(ctx->cpu)) | |
1012 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 1013 | |
320ae51f JA |
1014 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
1015 | ||
a57a178a CH |
1016 | spin_lock(&ctx->lock); |
1017 | __blk_mq_insert_request(hctx, rq, at_head); | |
1018 | spin_unlock(&ctx->lock); | |
320ae51f | 1019 | |
320ae51f JA |
1020 | if (run_queue) |
1021 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
1022 | |
1023 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
1024 | } |
1025 | ||
1026 | static void blk_mq_insert_requests(struct request_queue *q, | |
1027 | struct blk_mq_ctx *ctx, | |
1028 | struct list_head *list, | |
1029 | int depth, | |
1030 | bool from_schedule) | |
1031 | ||
1032 | { | |
1033 | struct blk_mq_hw_ctx *hctx; | |
1034 | struct blk_mq_ctx *current_ctx; | |
1035 | ||
1036 | trace_block_unplug(q, depth, !from_schedule); | |
1037 | ||
1038 | current_ctx = blk_mq_get_ctx(q); | |
1039 | ||
1040 | if (!cpu_online(ctx->cpu)) | |
1041 | ctx = current_ctx; | |
1042 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1043 | ||
1044 | /* | |
1045 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
1046 | * offline now | |
1047 | */ | |
1048 | spin_lock(&ctx->lock); | |
1049 | while (!list_empty(list)) { | |
1050 | struct request *rq; | |
1051 | ||
1052 | rq = list_first_entry(list, struct request, queuelist); | |
1053 | list_del_init(&rq->queuelist); | |
1054 | rq->mq_ctx = ctx; | |
cfd0c552 | 1055 | __blk_mq_insert_req_list(hctx, ctx, rq, false); |
320ae51f | 1056 | } |
cfd0c552 | 1057 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
1058 | spin_unlock(&ctx->lock); |
1059 | ||
320ae51f | 1060 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 1061 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
1062 | } |
1063 | ||
1064 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1065 | { | |
1066 | struct request *rqa = container_of(a, struct request, queuelist); | |
1067 | struct request *rqb = container_of(b, struct request, queuelist); | |
1068 | ||
1069 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1070 | (rqa->mq_ctx == rqb->mq_ctx && | |
1071 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1072 | } | |
1073 | ||
1074 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1075 | { | |
1076 | struct blk_mq_ctx *this_ctx; | |
1077 | struct request_queue *this_q; | |
1078 | struct request *rq; | |
1079 | LIST_HEAD(list); | |
1080 | LIST_HEAD(ctx_list); | |
1081 | unsigned int depth; | |
1082 | ||
1083 | list_splice_init(&plug->mq_list, &list); | |
1084 | ||
1085 | list_sort(NULL, &list, plug_ctx_cmp); | |
1086 | ||
1087 | this_q = NULL; | |
1088 | this_ctx = NULL; | |
1089 | depth = 0; | |
1090 | ||
1091 | while (!list_empty(&list)) { | |
1092 | rq = list_entry_rq(list.next); | |
1093 | list_del_init(&rq->queuelist); | |
1094 | BUG_ON(!rq->q); | |
1095 | if (rq->mq_ctx != this_ctx) { | |
1096 | if (this_ctx) { | |
1097 | blk_mq_insert_requests(this_q, this_ctx, | |
1098 | &ctx_list, depth, | |
1099 | from_schedule); | |
1100 | } | |
1101 | ||
1102 | this_ctx = rq->mq_ctx; | |
1103 | this_q = rq->q; | |
1104 | depth = 0; | |
1105 | } | |
1106 | ||
1107 | depth++; | |
1108 | list_add_tail(&rq->queuelist, &ctx_list); | |
1109 | } | |
1110 | ||
1111 | /* | |
1112 | * If 'this_ctx' is set, we know we have entries to complete | |
1113 | * on 'ctx_list'. Do those. | |
1114 | */ | |
1115 | if (this_ctx) { | |
1116 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1117 | from_schedule); | |
1118 | } | |
1119 | } | |
1120 | ||
1121 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1122 | { | |
1123 | init_request_from_bio(rq, bio); | |
4b570521 | 1124 | |
a21f2a3e | 1125 | blk_account_io_start(rq, 1); |
320ae51f JA |
1126 | } |
1127 | ||
274a5843 JA |
1128 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1129 | { | |
1130 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1131 | !blk_queue_nomerges(hctx->queue); | |
1132 | } | |
1133 | ||
07068d5b JA |
1134 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1135 | struct blk_mq_ctx *ctx, | |
1136 | struct request *rq, struct bio *bio) | |
320ae51f | 1137 | { |
e18378a6 | 1138 | if (!hctx_allow_merges(hctx) || !bio_mergeable(bio)) { |
07068d5b JA |
1139 | blk_mq_bio_to_request(rq, bio); |
1140 | spin_lock(&ctx->lock); | |
1141 | insert_rq: | |
1142 | __blk_mq_insert_request(hctx, rq, false); | |
1143 | spin_unlock(&ctx->lock); | |
1144 | return false; | |
1145 | } else { | |
274a5843 JA |
1146 | struct request_queue *q = hctx->queue; |
1147 | ||
07068d5b JA |
1148 | spin_lock(&ctx->lock); |
1149 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1150 | blk_mq_bio_to_request(rq, bio); | |
1151 | goto insert_rq; | |
1152 | } | |
320ae51f | 1153 | |
07068d5b JA |
1154 | spin_unlock(&ctx->lock); |
1155 | __blk_mq_free_request(hctx, ctx, rq); | |
1156 | return true; | |
14ec77f3 | 1157 | } |
07068d5b | 1158 | } |
14ec77f3 | 1159 | |
07068d5b JA |
1160 | struct blk_map_ctx { |
1161 | struct blk_mq_hw_ctx *hctx; | |
1162 | struct blk_mq_ctx *ctx; | |
1163 | }; | |
1164 | ||
1165 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1166 | struct bio *bio, | |
1167 | struct blk_map_ctx *data) | |
1168 | { | |
1169 | struct blk_mq_hw_ctx *hctx; | |
1170 | struct blk_mq_ctx *ctx; | |
1171 | struct request *rq; | |
1172 | int rw = bio_data_dir(bio); | |
cb96a42c | 1173 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1174 | |
3ef28e83 | 1175 | blk_queue_enter_live(q); |
320ae51f JA |
1176 | ctx = blk_mq_get_ctx(q); |
1177 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1178 | ||
07068d5b | 1179 | if (rw_is_sync(bio->bi_rw)) |
27fbf4e8 | 1180 | rw |= REQ_SYNC; |
07068d5b | 1181 | |
320ae51f | 1182 | trace_block_getrq(q, bio, rw); |
6f3b0e8b | 1183 | blk_mq_set_alloc_data(&alloc_data, q, BLK_MQ_REQ_NOWAIT, ctx, hctx); |
cb96a42c | 1184 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
5dee8577 | 1185 | if (unlikely(!rq)) { |
793597a6 | 1186 | __blk_mq_run_hw_queue(hctx); |
320ae51f JA |
1187 | blk_mq_put_ctx(ctx); |
1188 | trace_block_sleeprq(q, bio, rw); | |
793597a6 CH |
1189 | |
1190 | ctx = blk_mq_get_ctx(q); | |
320ae51f | 1191 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
6f3b0e8b | 1192 | blk_mq_set_alloc_data(&alloc_data, q, 0, ctx, hctx); |
cb96a42c ML |
1193 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
1194 | ctx = alloc_data.ctx; | |
1195 | hctx = alloc_data.hctx; | |
320ae51f JA |
1196 | } |
1197 | ||
1198 | hctx->queued++; | |
07068d5b JA |
1199 | data->hctx = hctx; |
1200 | data->ctx = ctx; | |
1201 | return rq; | |
1202 | } | |
1203 | ||
7b371636 | 1204 | static int blk_mq_direct_issue_request(struct request *rq, blk_qc_t *cookie) |
f984df1f SL |
1205 | { |
1206 | int ret; | |
1207 | struct request_queue *q = rq->q; | |
1208 | struct blk_mq_hw_ctx *hctx = q->mq_ops->map_queue(q, | |
1209 | rq->mq_ctx->cpu); | |
1210 | struct blk_mq_queue_data bd = { | |
1211 | .rq = rq, | |
1212 | .list = NULL, | |
1213 | .last = 1 | |
1214 | }; | |
7b371636 | 1215 | blk_qc_t new_cookie = blk_tag_to_qc_t(rq->tag, hctx->queue_num); |
f984df1f SL |
1216 | |
1217 | /* | |
1218 | * For OK queue, we are done. For error, kill it. Any other | |
1219 | * error (busy), just add it to our list as we previously | |
1220 | * would have done | |
1221 | */ | |
1222 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
7b371636 JA |
1223 | if (ret == BLK_MQ_RQ_QUEUE_OK) { |
1224 | *cookie = new_cookie; | |
f984df1f | 1225 | return 0; |
7b371636 | 1226 | } |
f984df1f | 1227 | |
7b371636 JA |
1228 | __blk_mq_requeue_request(rq); |
1229 | ||
1230 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1231 | *cookie = BLK_QC_T_NONE; | |
1232 | rq->errors = -EIO; | |
1233 | blk_mq_end_request(rq, rq->errors); | |
1234 | return 0; | |
f984df1f | 1235 | } |
7b371636 JA |
1236 | |
1237 | return -1; | |
f984df1f SL |
1238 | } |
1239 | ||
07068d5b JA |
1240 | /* |
1241 | * Multiple hardware queue variant. This will not use per-process plugs, | |
1242 | * but will attempt to bypass the hctx queueing if we can go straight to | |
1243 | * hardware for SYNC IO. | |
1244 | */ | |
dece1635 | 1245 | static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) |
07068d5b JA |
1246 | { |
1247 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1248 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1249 | struct blk_map_ctx data; | |
1250 | struct request *rq; | |
f984df1f SL |
1251 | unsigned int request_count = 0; |
1252 | struct blk_plug *plug; | |
5b3f341f | 1253 | struct request *same_queue_rq = NULL; |
7b371636 | 1254 | blk_qc_t cookie; |
07068d5b JA |
1255 | |
1256 | blk_queue_bounce(q, &bio); | |
1257 | ||
1258 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1259 | bio_io_error(bio); |
dece1635 | 1260 | return BLK_QC_T_NONE; |
07068d5b JA |
1261 | } |
1262 | ||
54efd50b KO |
1263 | blk_queue_split(q, &bio, q->bio_split); |
1264 | ||
0809e3ac JM |
1265 | if (!is_flush_fua && !blk_queue_nomerges(q)) { |
1266 | if (blk_attempt_plug_merge(q, bio, &request_count, | |
1267 | &same_queue_rq)) | |
dece1635 | 1268 | return BLK_QC_T_NONE; |
0809e3ac JM |
1269 | } else |
1270 | request_count = blk_plug_queued_count(q); | |
f984df1f | 1271 | |
07068d5b JA |
1272 | rq = blk_mq_map_request(q, bio, &data); |
1273 | if (unlikely(!rq)) | |
dece1635 | 1274 | return BLK_QC_T_NONE; |
07068d5b | 1275 | |
7b371636 | 1276 | cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num); |
07068d5b JA |
1277 | |
1278 | if (unlikely(is_flush_fua)) { | |
1279 | blk_mq_bio_to_request(rq, bio); | |
1280 | blk_insert_flush(rq); | |
1281 | goto run_queue; | |
1282 | } | |
1283 | ||
f984df1f | 1284 | plug = current->plug; |
e167dfb5 JA |
1285 | /* |
1286 | * If the driver supports defer issued based on 'last', then | |
1287 | * queue it up like normal since we can potentially save some | |
1288 | * CPU this way. | |
1289 | */ | |
f984df1f SL |
1290 | if (((plug && !blk_queue_nomerges(q)) || is_sync) && |
1291 | !(data.hctx->flags & BLK_MQ_F_DEFER_ISSUE)) { | |
1292 | struct request *old_rq = NULL; | |
07068d5b JA |
1293 | |
1294 | blk_mq_bio_to_request(rq, bio); | |
07068d5b JA |
1295 | |
1296 | /* | |
b094f89c | 1297 | * We do limited pluging. If the bio can be merged, do that. |
f984df1f SL |
1298 | * Otherwise the existing request in the plug list will be |
1299 | * issued. So the plug list will have one request at most | |
07068d5b | 1300 | */ |
f984df1f | 1301 | if (plug) { |
5b3f341f SL |
1302 | /* |
1303 | * The plug list might get flushed before this. If that | |
b094f89c JA |
1304 | * happens, same_queue_rq is invalid and plug list is |
1305 | * empty | |
1306 | */ | |
5b3f341f SL |
1307 | if (same_queue_rq && !list_empty(&plug->mq_list)) { |
1308 | old_rq = same_queue_rq; | |
f984df1f | 1309 | list_del_init(&old_rq->queuelist); |
07068d5b | 1310 | } |
f984df1f SL |
1311 | list_add_tail(&rq->queuelist, &plug->mq_list); |
1312 | } else /* is_sync */ | |
1313 | old_rq = rq; | |
1314 | blk_mq_put_ctx(data.ctx); | |
1315 | if (!old_rq) | |
7b371636 JA |
1316 | goto done; |
1317 | if (!blk_mq_direct_issue_request(old_rq, &cookie)) | |
1318 | goto done; | |
f984df1f | 1319 | blk_mq_insert_request(old_rq, false, true, true); |
7b371636 | 1320 | goto done; |
07068d5b JA |
1321 | } |
1322 | ||
1323 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { | |
1324 | /* | |
1325 | * For a SYNC request, send it to the hardware immediately. For | |
1326 | * an ASYNC request, just ensure that we run it later on. The | |
1327 | * latter allows for merging opportunities and more efficient | |
1328 | * dispatching. | |
1329 | */ | |
1330 | run_queue: | |
1331 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
1332 | } | |
07068d5b | 1333 | blk_mq_put_ctx(data.ctx); |
7b371636 JA |
1334 | done: |
1335 | return cookie; | |
07068d5b JA |
1336 | } |
1337 | ||
1338 | /* | |
1339 | * Single hardware queue variant. This will attempt to use any per-process | |
1340 | * plug for merging and IO deferral. | |
1341 | */ | |
dece1635 | 1342 | static blk_qc_t blk_sq_make_request(struct request_queue *q, struct bio *bio) |
07068d5b JA |
1343 | { |
1344 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1345 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
e6c4438b JM |
1346 | struct blk_plug *plug; |
1347 | unsigned int request_count = 0; | |
07068d5b JA |
1348 | struct blk_map_ctx data; |
1349 | struct request *rq; | |
7b371636 | 1350 | blk_qc_t cookie; |
07068d5b | 1351 | |
07068d5b JA |
1352 | blk_queue_bounce(q, &bio); |
1353 | ||
1354 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1355 | bio_io_error(bio); |
dece1635 | 1356 | return BLK_QC_T_NONE; |
07068d5b JA |
1357 | } |
1358 | ||
54efd50b KO |
1359 | blk_queue_split(q, &bio, q->bio_split); |
1360 | ||
e6c4438b | 1361 | if (!is_flush_fua && !blk_queue_nomerges(q) && |
5b3f341f | 1362 | blk_attempt_plug_merge(q, bio, &request_count, NULL)) |
dece1635 | 1363 | return BLK_QC_T_NONE; |
07068d5b JA |
1364 | |
1365 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec | 1366 | if (unlikely(!rq)) |
dece1635 | 1367 | return BLK_QC_T_NONE; |
320ae51f | 1368 | |
7b371636 | 1369 | cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num); |
320ae51f JA |
1370 | |
1371 | if (unlikely(is_flush_fua)) { | |
1372 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1373 | blk_insert_flush(rq); |
1374 | goto run_queue; | |
1375 | } | |
1376 | ||
1377 | /* | |
1378 | * A task plug currently exists. Since this is completely lockless, | |
1379 | * utilize that to temporarily store requests until the task is | |
1380 | * either done or scheduled away. | |
1381 | */ | |
e6c4438b JM |
1382 | plug = current->plug; |
1383 | if (plug) { | |
1384 | blk_mq_bio_to_request(rq, bio); | |
676d0607 | 1385 | if (!request_count) |
e6c4438b | 1386 | trace_block_plug(q); |
b094f89c JA |
1387 | |
1388 | blk_mq_put_ctx(data.ctx); | |
1389 | ||
1390 | if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
e6c4438b JM |
1391 | blk_flush_plug_list(plug, false); |
1392 | trace_block_plug(q); | |
320ae51f | 1393 | } |
b094f89c | 1394 | |
e6c4438b | 1395 | list_add_tail(&rq->queuelist, &plug->mq_list); |
7b371636 | 1396 | return cookie; |
320ae51f JA |
1397 | } |
1398 | ||
07068d5b JA |
1399 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1400 | /* | |
1401 | * For a SYNC request, send it to the hardware immediately. For | |
1402 | * an ASYNC request, just ensure that we run it later on. The | |
1403 | * latter allows for merging opportunities and more efficient | |
1404 | * dispatching. | |
1405 | */ | |
1406 | run_queue: | |
1407 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1408 | } |
1409 | ||
07068d5b | 1410 | blk_mq_put_ctx(data.ctx); |
7b371636 | 1411 | return cookie; |
320ae51f JA |
1412 | } |
1413 | ||
1414 | /* | |
1415 | * Default mapping to a software queue, since we use one per CPU. | |
1416 | */ | |
1417 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1418 | { | |
1419 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1420 | } | |
1421 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1422 | ||
24d2f903 CH |
1423 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1424 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1425 | { |
e9b267d9 | 1426 | struct page *page; |
320ae51f | 1427 | |
24d2f903 | 1428 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1429 | int i; |
320ae51f | 1430 | |
24d2f903 CH |
1431 | for (i = 0; i < tags->nr_tags; i++) { |
1432 | if (!tags->rqs[i]) | |
e9b267d9 | 1433 | continue; |
24d2f903 CH |
1434 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1435 | hctx_idx, i); | |
a5164405 | 1436 | tags->rqs[i] = NULL; |
e9b267d9 | 1437 | } |
320ae51f | 1438 | } |
320ae51f | 1439 | |
24d2f903 CH |
1440 | while (!list_empty(&tags->page_list)) { |
1441 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1442 | list_del_init(&page->lru); |
f75782e4 CM |
1443 | /* |
1444 | * Remove kmemleak object previously allocated in | |
1445 | * blk_mq_init_rq_map(). | |
1446 | */ | |
1447 | kmemleak_free(page_address(page)); | |
320ae51f JA |
1448 | __free_pages(page, page->private); |
1449 | } | |
1450 | ||
24d2f903 | 1451 | kfree(tags->rqs); |
320ae51f | 1452 | |
24d2f903 | 1453 | blk_mq_free_tags(tags); |
320ae51f JA |
1454 | } |
1455 | ||
1456 | static size_t order_to_size(unsigned int order) | |
1457 | { | |
4ca08500 | 1458 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1459 | } |
1460 | ||
24d2f903 CH |
1461 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1462 | unsigned int hctx_idx) | |
320ae51f | 1463 | { |
24d2f903 | 1464 | struct blk_mq_tags *tags; |
320ae51f JA |
1465 | unsigned int i, j, entries_per_page, max_order = 4; |
1466 | size_t rq_size, left; | |
1467 | ||
24d2f903 | 1468 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
24391c0d SL |
1469 | set->numa_node, |
1470 | BLK_MQ_FLAG_TO_ALLOC_POLICY(set->flags)); | |
24d2f903 CH |
1471 | if (!tags) |
1472 | return NULL; | |
320ae51f | 1473 | |
24d2f903 CH |
1474 | INIT_LIST_HEAD(&tags->page_list); |
1475 | ||
a5164405 JA |
1476 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1477 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1478 | set->numa_node); | |
24d2f903 CH |
1479 | if (!tags->rqs) { |
1480 | blk_mq_free_tags(tags); | |
1481 | return NULL; | |
1482 | } | |
320ae51f JA |
1483 | |
1484 | /* | |
1485 | * rq_size is the size of the request plus driver payload, rounded | |
1486 | * to the cacheline size | |
1487 | */ | |
24d2f903 | 1488 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1489 | cache_line_size()); |
24d2f903 | 1490 | left = rq_size * set->queue_depth; |
320ae51f | 1491 | |
24d2f903 | 1492 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1493 | int this_order = max_order; |
1494 | struct page *page; | |
1495 | int to_do; | |
1496 | void *p; | |
1497 | ||
b3a834b1 | 1498 | while (this_order && left < order_to_size(this_order - 1)) |
320ae51f JA |
1499 | this_order--; |
1500 | ||
1501 | do { | |
a5164405 | 1502 | page = alloc_pages_node(set->numa_node, |
ac211175 | 1503 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO, |
a5164405 | 1504 | this_order); |
320ae51f JA |
1505 | if (page) |
1506 | break; | |
1507 | if (!this_order--) | |
1508 | break; | |
1509 | if (order_to_size(this_order) < rq_size) | |
1510 | break; | |
1511 | } while (1); | |
1512 | ||
1513 | if (!page) | |
24d2f903 | 1514 | goto fail; |
320ae51f JA |
1515 | |
1516 | page->private = this_order; | |
24d2f903 | 1517 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1518 | |
1519 | p = page_address(page); | |
f75782e4 CM |
1520 | /* |
1521 | * Allow kmemleak to scan these pages as they contain pointers | |
1522 | * to additional allocations like via ops->init_request(). | |
1523 | */ | |
1524 | kmemleak_alloc(p, order_to_size(this_order), 1, GFP_KERNEL); | |
320ae51f | 1525 | entries_per_page = order_to_size(this_order) / rq_size; |
24d2f903 | 1526 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1527 | left -= to_do * rq_size; |
1528 | for (j = 0; j < to_do; j++) { | |
24d2f903 CH |
1529 | tags->rqs[i] = p; |
1530 | if (set->ops->init_request) { | |
1531 | if (set->ops->init_request(set->driver_data, | |
1532 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1533 | set->numa_node)) { |
1534 | tags->rqs[i] = NULL; | |
24d2f903 | 1535 | goto fail; |
a5164405 | 1536 | } |
e9b267d9 CH |
1537 | } |
1538 | ||
320ae51f JA |
1539 | p += rq_size; |
1540 | i++; | |
1541 | } | |
1542 | } | |
24d2f903 | 1543 | return tags; |
320ae51f | 1544 | |
24d2f903 | 1545 | fail: |
24d2f903 CH |
1546 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1547 | return NULL; | |
320ae51f JA |
1548 | } |
1549 | ||
1429d7c9 JA |
1550 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1551 | { | |
1552 | kfree(bitmap->map); | |
1553 | } | |
1554 | ||
1555 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1556 | { | |
1557 | unsigned int bpw = 8, total, num_maps, i; | |
1558 | ||
1559 | bitmap->bits_per_word = bpw; | |
1560 | ||
1561 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1562 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1563 | GFP_KERNEL, node); | |
1564 | if (!bitmap->map) | |
1565 | return -ENOMEM; | |
1566 | ||
1429d7c9 JA |
1567 | total = nr_cpu_ids; |
1568 | for (i = 0; i < num_maps; i++) { | |
1569 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1570 | total -= bitmap->map[i].depth; | |
1571 | } | |
1572 | ||
1573 | return 0; | |
1574 | } | |
1575 | ||
484b4061 JA |
1576 | static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) |
1577 | { | |
1578 | struct request_queue *q = hctx->queue; | |
1579 | struct blk_mq_ctx *ctx; | |
1580 | LIST_HEAD(tmp); | |
1581 | ||
1582 | /* | |
1583 | * Move ctx entries to new CPU, if this one is going away. | |
1584 | */ | |
1585 | ctx = __blk_mq_get_ctx(q, cpu); | |
1586 | ||
1587 | spin_lock(&ctx->lock); | |
1588 | if (!list_empty(&ctx->rq_list)) { | |
1589 | list_splice_init(&ctx->rq_list, &tmp); | |
1590 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1591 | } | |
1592 | spin_unlock(&ctx->lock); | |
1593 | ||
1594 | if (list_empty(&tmp)) | |
1595 | return NOTIFY_OK; | |
1596 | ||
1597 | ctx = blk_mq_get_ctx(q); | |
1598 | spin_lock(&ctx->lock); | |
1599 | ||
1600 | while (!list_empty(&tmp)) { | |
1601 | struct request *rq; | |
1602 | ||
1603 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1604 | rq->mq_ctx = ctx; | |
1605 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1606 | } | |
1607 | ||
1608 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1609 | blk_mq_hctx_mark_pending(hctx, ctx); | |
1610 | ||
1611 | spin_unlock(&ctx->lock); | |
1612 | ||
1613 | blk_mq_run_hw_queue(hctx, true); | |
1614 | blk_mq_put_ctx(ctx); | |
1615 | return NOTIFY_OK; | |
1616 | } | |
1617 | ||
484b4061 JA |
1618 | static int blk_mq_hctx_notify(void *data, unsigned long action, |
1619 | unsigned int cpu) | |
1620 | { | |
1621 | struct blk_mq_hw_ctx *hctx = data; | |
1622 | ||
1623 | if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) | |
1624 | return blk_mq_hctx_cpu_offline(hctx, cpu); | |
2a34c087 ML |
1625 | |
1626 | /* | |
1627 | * In case of CPU online, tags may be reallocated | |
1628 | * in blk_mq_map_swqueue() after mapping is updated. | |
1629 | */ | |
484b4061 JA |
1630 | |
1631 | return NOTIFY_OK; | |
1632 | } | |
1633 | ||
c3b4afca | 1634 | /* hctx->ctxs will be freed in queue's release handler */ |
08e98fc6 ML |
1635 | static void blk_mq_exit_hctx(struct request_queue *q, |
1636 | struct blk_mq_tag_set *set, | |
1637 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
1638 | { | |
f70ced09 ML |
1639 | unsigned flush_start_tag = set->queue_depth; |
1640 | ||
08e98fc6 ML |
1641 | blk_mq_tag_idle(hctx); |
1642 | ||
f70ced09 ML |
1643 | if (set->ops->exit_request) |
1644 | set->ops->exit_request(set->driver_data, | |
1645 | hctx->fq->flush_rq, hctx_idx, | |
1646 | flush_start_tag + hctx_idx); | |
1647 | ||
08e98fc6 ML |
1648 | if (set->ops->exit_hctx) |
1649 | set->ops->exit_hctx(hctx, hctx_idx); | |
1650 | ||
1651 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
f70ced09 | 1652 | blk_free_flush_queue(hctx->fq); |
08e98fc6 ML |
1653 | blk_mq_free_bitmap(&hctx->ctx_map); |
1654 | } | |
1655 | ||
624dbe47 ML |
1656 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1657 | struct blk_mq_tag_set *set, int nr_queue) | |
1658 | { | |
1659 | struct blk_mq_hw_ctx *hctx; | |
1660 | unsigned int i; | |
1661 | ||
1662 | queue_for_each_hw_ctx(q, hctx, i) { | |
1663 | if (i == nr_queue) | |
1664 | break; | |
08e98fc6 | 1665 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 1666 | } |
624dbe47 ML |
1667 | } |
1668 | ||
1669 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1670 | struct blk_mq_tag_set *set) | |
1671 | { | |
1672 | struct blk_mq_hw_ctx *hctx; | |
1673 | unsigned int i; | |
1674 | ||
e09aae7e | 1675 | queue_for_each_hw_ctx(q, hctx, i) |
624dbe47 | 1676 | free_cpumask_var(hctx->cpumask); |
624dbe47 ML |
1677 | } |
1678 | ||
08e98fc6 ML |
1679 | static int blk_mq_init_hctx(struct request_queue *q, |
1680 | struct blk_mq_tag_set *set, | |
1681 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 1682 | { |
08e98fc6 | 1683 | int node; |
f70ced09 | 1684 | unsigned flush_start_tag = set->queue_depth; |
08e98fc6 ML |
1685 | |
1686 | node = hctx->numa_node; | |
1687 | if (node == NUMA_NO_NODE) | |
1688 | node = hctx->numa_node = set->numa_node; | |
1689 | ||
1690 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); | |
1691 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
1692 | spin_lock_init(&hctx->lock); | |
1693 | INIT_LIST_HEAD(&hctx->dispatch); | |
1694 | hctx->queue = q; | |
1695 | hctx->queue_num = hctx_idx; | |
2404e607 | 1696 | hctx->flags = set->flags & ~BLK_MQ_F_TAG_SHARED; |
08e98fc6 ML |
1697 | |
1698 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1699 | blk_mq_hctx_notify, hctx); | |
1700 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1701 | ||
1702 | hctx->tags = set->tags[hctx_idx]; | |
320ae51f JA |
1703 | |
1704 | /* | |
08e98fc6 ML |
1705 | * Allocate space for all possible cpus to avoid allocation at |
1706 | * runtime | |
320ae51f | 1707 | */ |
08e98fc6 ML |
1708 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), |
1709 | GFP_KERNEL, node); | |
1710 | if (!hctx->ctxs) | |
1711 | goto unregister_cpu_notifier; | |
320ae51f | 1712 | |
08e98fc6 ML |
1713 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
1714 | goto free_ctxs; | |
320ae51f | 1715 | |
08e98fc6 | 1716 | hctx->nr_ctx = 0; |
320ae51f | 1717 | |
08e98fc6 ML |
1718 | if (set->ops->init_hctx && |
1719 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
1720 | goto free_bitmap; | |
320ae51f | 1721 | |
f70ced09 ML |
1722 | hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); |
1723 | if (!hctx->fq) | |
1724 | goto exit_hctx; | |
320ae51f | 1725 | |
f70ced09 ML |
1726 | if (set->ops->init_request && |
1727 | set->ops->init_request(set->driver_data, | |
1728 | hctx->fq->flush_rq, hctx_idx, | |
1729 | flush_start_tag + hctx_idx, node)) | |
1730 | goto free_fq; | |
320ae51f | 1731 | |
08e98fc6 | 1732 | return 0; |
320ae51f | 1733 | |
f70ced09 ML |
1734 | free_fq: |
1735 | kfree(hctx->fq); | |
1736 | exit_hctx: | |
1737 | if (set->ops->exit_hctx) | |
1738 | set->ops->exit_hctx(hctx, hctx_idx); | |
08e98fc6 ML |
1739 | free_bitmap: |
1740 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1741 | free_ctxs: | |
1742 | kfree(hctx->ctxs); | |
1743 | unregister_cpu_notifier: | |
1744 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
320ae51f | 1745 | |
08e98fc6 ML |
1746 | return -1; |
1747 | } | |
320ae51f | 1748 | |
320ae51f JA |
1749 | static void blk_mq_init_cpu_queues(struct request_queue *q, |
1750 | unsigned int nr_hw_queues) | |
1751 | { | |
1752 | unsigned int i; | |
1753 | ||
1754 | for_each_possible_cpu(i) { | |
1755 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1756 | struct blk_mq_hw_ctx *hctx; | |
1757 | ||
1758 | memset(__ctx, 0, sizeof(*__ctx)); | |
1759 | __ctx->cpu = i; | |
1760 | spin_lock_init(&__ctx->lock); | |
1761 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1762 | __ctx->queue = q; | |
1763 | ||
1764 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1765 | if (!cpu_online(i)) |
1766 | continue; | |
1767 | ||
e4043dcf | 1768 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1769 | |
320ae51f JA |
1770 | /* |
1771 | * Set local node, IFF we have more than one hw queue. If | |
1772 | * not, we remain on the home node of the device | |
1773 | */ | |
1774 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
bffed457 | 1775 | hctx->numa_node = local_memory_node(cpu_to_node(i)); |
320ae51f JA |
1776 | } |
1777 | } | |
1778 | ||
5778322e AM |
1779 | static void blk_mq_map_swqueue(struct request_queue *q, |
1780 | const struct cpumask *online_mask) | |
320ae51f JA |
1781 | { |
1782 | unsigned int i; | |
1783 | struct blk_mq_hw_ctx *hctx; | |
1784 | struct blk_mq_ctx *ctx; | |
2a34c087 | 1785 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 1786 | |
60de074b AM |
1787 | /* |
1788 | * Avoid others reading imcomplete hctx->cpumask through sysfs | |
1789 | */ | |
1790 | mutex_lock(&q->sysfs_lock); | |
1791 | ||
320ae51f | 1792 | queue_for_each_hw_ctx(q, hctx, i) { |
e4043dcf | 1793 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1794 | hctx->nr_ctx = 0; |
1795 | } | |
1796 | ||
1797 | /* | |
1798 | * Map software to hardware queues | |
1799 | */ | |
897bb0c7 | 1800 | for_each_possible_cpu(i) { |
320ae51f | 1801 | /* If the cpu isn't online, the cpu is mapped to first hctx */ |
5778322e | 1802 | if (!cpumask_test_cpu(i, online_mask)) |
e4043dcf JA |
1803 | continue; |
1804 | ||
897bb0c7 | 1805 | ctx = per_cpu_ptr(q->queue_ctx, i); |
320ae51f | 1806 | hctx = q->mq_ops->map_queue(q, i); |
868f2f0b | 1807 | |
e4043dcf | 1808 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1809 | ctx->index_hw = hctx->nr_ctx; |
1810 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1811 | } | |
506e931f | 1812 | |
60de074b AM |
1813 | mutex_unlock(&q->sysfs_lock); |
1814 | ||
506e931f | 1815 | queue_for_each_hw_ctx(q, hctx, i) { |
889fa31f CY |
1816 | struct blk_mq_ctxmap *map = &hctx->ctx_map; |
1817 | ||
484b4061 | 1818 | /* |
a68aafa5 JA |
1819 | * If no software queues are mapped to this hardware queue, |
1820 | * disable it and free the request entries. | |
484b4061 JA |
1821 | */ |
1822 | if (!hctx->nr_ctx) { | |
484b4061 JA |
1823 | if (set->tags[i]) { |
1824 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1825 | set->tags[i] = NULL; | |
484b4061 | 1826 | } |
2a34c087 | 1827 | hctx->tags = NULL; |
484b4061 JA |
1828 | continue; |
1829 | } | |
1830 | ||
2a34c087 ML |
1831 | /* unmapped hw queue can be remapped after CPU topo changed */ |
1832 | if (!set->tags[i]) | |
1833 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1834 | hctx->tags = set->tags[i]; | |
1835 | WARN_ON(!hctx->tags); | |
1836 | ||
e0e827b9 | 1837 | cpumask_copy(hctx->tags->cpumask, hctx->cpumask); |
889fa31f CY |
1838 | /* |
1839 | * Set the map size to the number of mapped software queues. | |
1840 | * This is more accurate and more efficient than looping | |
1841 | * over all possibly mapped software queues. | |
1842 | */ | |
569fd0ce | 1843 | map->size = DIV_ROUND_UP(hctx->nr_ctx, map->bits_per_word); |
889fa31f | 1844 | |
484b4061 JA |
1845 | /* |
1846 | * Initialize batch roundrobin counts | |
1847 | */ | |
506e931f JA |
1848 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1849 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1850 | } | |
320ae51f JA |
1851 | } |
1852 | ||
2404e607 | 1853 | static void queue_set_hctx_shared(struct request_queue *q, bool shared) |
0d2602ca JA |
1854 | { |
1855 | struct blk_mq_hw_ctx *hctx; | |
0d2602ca JA |
1856 | int i; |
1857 | ||
2404e607 JM |
1858 | queue_for_each_hw_ctx(q, hctx, i) { |
1859 | if (shared) | |
1860 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1861 | else | |
1862 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1863 | } | |
1864 | } | |
1865 | ||
1866 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set, bool shared) | |
1867 | { | |
1868 | struct request_queue *q; | |
0d2602ca JA |
1869 | |
1870 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1871 | blk_mq_freeze_queue(q); | |
2404e607 | 1872 | queue_set_hctx_shared(q, shared); |
0d2602ca JA |
1873 | blk_mq_unfreeze_queue(q); |
1874 | } | |
1875 | } | |
1876 | ||
1877 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1878 | { | |
1879 | struct blk_mq_tag_set *set = q->tag_set; | |
1880 | ||
0d2602ca JA |
1881 | mutex_lock(&set->tag_list_lock); |
1882 | list_del_init(&q->tag_set_list); | |
2404e607 JM |
1883 | if (list_is_singular(&set->tag_list)) { |
1884 | /* just transitioned to unshared */ | |
1885 | set->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1886 | /* update existing queue */ | |
1887 | blk_mq_update_tag_set_depth(set, false); | |
1888 | } | |
0d2602ca | 1889 | mutex_unlock(&set->tag_list_lock); |
0d2602ca JA |
1890 | } |
1891 | ||
1892 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1893 | struct request_queue *q) | |
1894 | { | |
1895 | q->tag_set = set; | |
1896 | ||
1897 | mutex_lock(&set->tag_list_lock); | |
2404e607 JM |
1898 | |
1899 | /* Check to see if we're transitioning to shared (from 1 to 2 queues). */ | |
1900 | if (!list_empty(&set->tag_list) && !(set->flags & BLK_MQ_F_TAG_SHARED)) { | |
1901 | set->flags |= BLK_MQ_F_TAG_SHARED; | |
1902 | /* update existing queue */ | |
1903 | blk_mq_update_tag_set_depth(set, true); | |
1904 | } | |
1905 | if (set->flags & BLK_MQ_F_TAG_SHARED) | |
1906 | queue_set_hctx_shared(q, true); | |
0d2602ca | 1907 | list_add_tail(&q->tag_set_list, &set->tag_list); |
2404e607 | 1908 | |
0d2602ca JA |
1909 | mutex_unlock(&set->tag_list_lock); |
1910 | } | |
1911 | ||
e09aae7e ML |
1912 | /* |
1913 | * It is the actual release handler for mq, but we do it from | |
1914 | * request queue's release handler for avoiding use-after-free | |
1915 | * and headache because q->mq_kobj shouldn't have been introduced, | |
1916 | * but we can't group ctx/kctx kobj without it. | |
1917 | */ | |
1918 | void blk_mq_release(struct request_queue *q) | |
1919 | { | |
1920 | struct blk_mq_hw_ctx *hctx; | |
1921 | unsigned int i; | |
1922 | ||
1923 | /* hctx kobj stays in hctx */ | |
c3b4afca ML |
1924 | queue_for_each_hw_ctx(q, hctx, i) { |
1925 | if (!hctx) | |
1926 | continue; | |
1927 | kfree(hctx->ctxs); | |
e09aae7e | 1928 | kfree(hctx); |
c3b4afca | 1929 | } |
e09aae7e | 1930 | |
a723bab3 AM |
1931 | kfree(q->mq_map); |
1932 | q->mq_map = NULL; | |
1933 | ||
e09aae7e ML |
1934 | kfree(q->queue_hw_ctx); |
1935 | ||
1936 | /* ctx kobj stays in queue_ctx */ | |
1937 | free_percpu(q->queue_ctx); | |
1938 | } | |
1939 | ||
24d2f903 | 1940 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
b62c21b7 MS |
1941 | { |
1942 | struct request_queue *uninit_q, *q; | |
1943 | ||
1944 | uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); | |
1945 | if (!uninit_q) | |
1946 | return ERR_PTR(-ENOMEM); | |
1947 | ||
1948 | q = blk_mq_init_allocated_queue(set, uninit_q); | |
1949 | if (IS_ERR(q)) | |
1950 | blk_cleanup_queue(uninit_q); | |
1951 | ||
1952 | return q; | |
1953 | } | |
1954 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1955 | ||
868f2f0b KB |
1956 | static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, |
1957 | struct request_queue *q) | |
320ae51f | 1958 | { |
868f2f0b KB |
1959 | int i, j; |
1960 | struct blk_mq_hw_ctx **hctxs = q->queue_hw_ctx; | |
f14bbe77 | 1961 | |
868f2f0b | 1962 | blk_mq_sysfs_unregister(q); |
24d2f903 | 1963 | for (i = 0; i < set->nr_hw_queues; i++) { |
868f2f0b | 1964 | int node; |
f14bbe77 | 1965 | |
868f2f0b KB |
1966 | if (hctxs[i]) |
1967 | continue; | |
1968 | ||
1969 | node = blk_mq_hw_queue_to_node(q->mq_map, i); | |
cdef54dd CH |
1970 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1971 | GFP_KERNEL, node); | |
320ae51f | 1972 | if (!hctxs[i]) |
868f2f0b | 1973 | break; |
320ae51f | 1974 | |
a86073e4 | 1975 | if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, |
868f2f0b KB |
1976 | node)) { |
1977 | kfree(hctxs[i]); | |
1978 | hctxs[i] = NULL; | |
1979 | break; | |
1980 | } | |
e4043dcf | 1981 | |
0d2602ca | 1982 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1983 | hctxs[i]->numa_node = node; |
320ae51f | 1984 | hctxs[i]->queue_num = i; |
868f2f0b KB |
1985 | |
1986 | if (blk_mq_init_hctx(q, set, hctxs[i], i)) { | |
1987 | free_cpumask_var(hctxs[i]->cpumask); | |
1988 | kfree(hctxs[i]); | |
1989 | hctxs[i] = NULL; | |
1990 | break; | |
1991 | } | |
1992 | blk_mq_hctx_kobj_init(hctxs[i]); | |
320ae51f | 1993 | } |
868f2f0b KB |
1994 | for (j = i; j < q->nr_hw_queues; j++) { |
1995 | struct blk_mq_hw_ctx *hctx = hctxs[j]; | |
1996 | ||
1997 | if (hctx) { | |
1998 | if (hctx->tags) { | |
1999 | blk_mq_free_rq_map(set, hctx->tags, j); | |
2000 | set->tags[j] = NULL; | |
2001 | } | |
2002 | blk_mq_exit_hctx(q, set, hctx, j); | |
2003 | free_cpumask_var(hctx->cpumask); | |
2004 | kobject_put(&hctx->kobj); | |
2005 | kfree(hctx->ctxs); | |
2006 | kfree(hctx); | |
2007 | hctxs[j] = NULL; | |
2008 | ||
2009 | } | |
2010 | } | |
2011 | q->nr_hw_queues = i; | |
2012 | blk_mq_sysfs_register(q); | |
2013 | } | |
2014 | ||
2015 | struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, | |
2016 | struct request_queue *q) | |
2017 | { | |
66841672 ML |
2018 | /* mark the queue as mq asap */ |
2019 | q->mq_ops = set->ops; | |
2020 | ||
868f2f0b KB |
2021 | q->queue_ctx = alloc_percpu(struct blk_mq_ctx); |
2022 | if (!q->queue_ctx) | |
c7de5726 | 2023 | goto err_exit; |
868f2f0b KB |
2024 | |
2025 | q->queue_hw_ctx = kzalloc_node(nr_cpu_ids * sizeof(*(q->queue_hw_ctx)), | |
2026 | GFP_KERNEL, set->numa_node); | |
2027 | if (!q->queue_hw_ctx) | |
2028 | goto err_percpu; | |
2029 | ||
2030 | q->mq_map = blk_mq_make_queue_map(set); | |
2031 | if (!q->mq_map) | |
2032 | goto err_map; | |
2033 | ||
2034 | blk_mq_realloc_hw_ctxs(set, q); | |
2035 | if (!q->nr_hw_queues) | |
2036 | goto err_hctxs; | |
320ae51f | 2037 | |
287922eb | 2038 | INIT_WORK(&q->timeout_work, blk_mq_timeout_work); |
e56f698b | 2039 | blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); |
320ae51f JA |
2040 | |
2041 | q->nr_queues = nr_cpu_ids; | |
320ae51f | 2042 | |
94eddfbe | 2043 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 2044 | |
05f1dd53 JA |
2045 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
2046 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
2047 | ||
1be036e9 CH |
2048 | q->sg_reserved_size = INT_MAX; |
2049 | ||
6fca6a61 CH |
2050 | INIT_WORK(&q->requeue_work, blk_mq_requeue_work); |
2051 | INIT_LIST_HEAD(&q->requeue_list); | |
2052 | spin_lock_init(&q->requeue_lock); | |
2053 | ||
07068d5b JA |
2054 | if (q->nr_hw_queues > 1) |
2055 | blk_queue_make_request(q, blk_mq_make_request); | |
2056 | else | |
2057 | blk_queue_make_request(q, blk_sq_make_request); | |
2058 | ||
eba71768 JA |
2059 | /* |
2060 | * Do this after blk_queue_make_request() overrides it... | |
2061 | */ | |
2062 | q->nr_requests = set->queue_depth; | |
2063 | ||
24d2f903 CH |
2064 | if (set->ops->complete) |
2065 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 2066 | |
24d2f903 | 2067 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 2068 | |
5778322e | 2069 | get_online_cpus(); |
320ae51f | 2070 | mutex_lock(&all_q_mutex); |
320ae51f | 2071 | |
4593fdbe | 2072 | list_add_tail(&q->all_q_node, &all_q_list); |
0d2602ca | 2073 | blk_mq_add_queue_tag_set(set, q); |
5778322e | 2074 | blk_mq_map_swqueue(q, cpu_online_mask); |
484b4061 | 2075 | |
4593fdbe | 2076 | mutex_unlock(&all_q_mutex); |
5778322e | 2077 | put_online_cpus(); |
4593fdbe | 2078 | |
320ae51f | 2079 | return q; |
18741986 | 2080 | |
320ae51f | 2081 | err_hctxs: |
868f2f0b | 2082 | kfree(q->mq_map); |
f14bbe77 | 2083 | err_map: |
868f2f0b | 2084 | kfree(q->queue_hw_ctx); |
320ae51f | 2085 | err_percpu: |
868f2f0b | 2086 | free_percpu(q->queue_ctx); |
c7de5726 ML |
2087 | err_exit: |
2088 | q->mq_ops = NULL; | |
320ae51f JA |
2089 | return ERR_PTR(-ENOMEM); |
2090 | } | |
b62c21b7 | 2091 | EXPORT_SYMBOL(blk_mq_init_allocated_queue); |
320ae51f JA |
2092 | |
2093 | void blk_mq_free_queue(struct request_queue *q) | |
2094 | { | |
624dbe47 | 2095 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 2096 | |
0e626368 AM |
2097 | mutex_lock(&all_q_mutex); |
2098 | list_del_init(&q->all_q_node); | |
2099 | mutex_unlock(&all_q_mutex); | |
2100 | ||
0d2602ca JA |
2101 | blk_mq_del_queue_tag_set(q); |
2102 | ||
624dbe47 ML |
2103 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
2104 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 2105 | } |
320ae51f JA |
2106 | |
2107 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
5778322e AM |
2108 | static void blk_mq_queue_reinit(struct request_queue *q, |
2109 | const struct cpumask *online_mask) | |
320ae51f | 2110 | { |
4ecd4fef | 2111 | WARN_ON_ONCE(!atomic_read(&q->mq_freeze_depth)); |
320ae51f | 2112 | |
67aec14c JA |
2113 | blk_mq_sysfs_unregister(q); |
2114 | ||
5778322e | 2115 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues, online_mask); |
320ae51f JA |
2116 | |
2117 | /* | |
2118 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
2119 | * we should change hctx numa_node according to new topology (this | |
2120 | * involves free and re-allocate memory, worthy doing?) | |
2121 | */ | |
2122 | ||
5778322e | 2123 | blk_mq_map_swqueue(q, online_mask); |
320ae51f | 2124 | |
67aec14c | 2125 | blk_mq_sysfs_register(q); |
320ae51f JA |
2126 | } |
2127 | ||
f618ef7c PG |
2128 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
2129 | unsigned long action, void *hcpu) | |
320ae51f JA |
2130 | { |
2131 | struct request_queue *q; | |
5778322e AM |
2132 | int cpu = (unsigned long)hcpu; |
2133 | /* | |
2134 | * New online cpumask which is going to be set in this hotplug event. | |
2135 | * Declare this cpumasks as global as cpu-hotplug operation is invoked | |
2136 | * one-by-one and dynamically allocating this could result in a failure. | |
2137 | */ | |
2138 | static struct cpumask online_new; | |
320ae51f JA |
2139 | |
2140 | /* | |
5778322e AM |
2141 | * Before hotadded cpu starts handling requests, new mappings must |
2142 | * be established. Otherwise, these requests in hw queue might | |
2143 | * never be dispatched. | |
2144 | * | |
2145 | * For example, there is a single hw queue (hctx) and two CPU queues | |
2146 | * (ctx0 for CPU0, and ctx1 for CPU1). | |
2147 | * | |
2148 | * Now CPU1 is just onlined and a request is inserted into | |
2149 | * ctx1->rq_list and set bit0 in pending bitmap as ctx1->index_hw is | |
2150 | * still zero. | |
2151 | * | |
2152 | * And then while running hw queue, flush_busy_ctxs() finds bit0 is | |
2153 | * set in pending bitmap and tries to retrieve requests in | |
2154 | * hctx->ctxs[0]->rq_list. But htx->ctxs[0] is a pointer to ctx0, | |
2155 | * so the request in ctx1->rq_list is ignored. | |
320ae51f | 2156 | */ |
5778322e AM |
2157 | switch (action & ~CPU_TASKS_FROZEN) { |
2158 | case CPU_DEAD: | |
2159 | case CPU_UP_CANCELED: | |
2160 | cpumask_copy(&online_new, cpu_online_mask); | |
2161 | break; | |
2162 | case CPU_UP_PREPARE: | |
2163 | cpumask_copy(&online_new, cpu_online_mask); | |
2164 | cpumask_set_cpu(cpu, &online_new); | |
2165 | break; | |
2166 | default: | |
320ae51f | 2167 | return NOTIFY_OK; |
5778322e | 2168 | } |
320ae51f JA |
2169 | |
2170 | mutex_lock(&all_q_mutex); | |
f3af020b TH |
2171 | |
2172 | /* | |
2173 | * We need to freeze and reinit all existing queues. Freezing | |
2174 | * involves synchronous wait for an RCU grace period and doing it | |
2175 | * one by one may take a long time. Start freezing all queues in | |
2176 | * one swoop and then wait for the completions so that freezing can | |
2177 | * take place in parallel. | |
2178 | */ | |
2179 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2180 | blk_mq_freeze_queue_start(q); | |
f054b56c | 2181 | list_for_each_entry(q, &all_q_list, all_q_node) { |
f3af020b TH |
2182 | blk_mq_freeze_queue_wait(q); |
2183 | ||
f054b56c ML |
2184 | /* |
2185 | * timeout handler can't touch hw queue during the | |
2186 | * reinitialization | |
2187 | */ | |
2188 | del_timer_sync(&q->timeout); | |
2189 | } | |
2190 | ||
320ae51f | 2191 | list_for_each_entry(q, &all_q_list, all_q_node) |
5778322e | 2192 | blk_mq_queue_reinit(q, &online_new); |
f3af020b TH |
2193 | |
2194 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2195 | blk_mq_unfreeze_queue(q); | |
2196 | ||
320ae51f JA |
2197 | mutex_unlock(&all_q_mutex); |
2198 | return NOTIFY_OK; | |
2199 | } | |
2200 | ||
a5164405 JA |
2201 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
2202 | { | |
2203 | int i; | |
2204 | ||
2205 | for (i = 0; i < set->nr_hw_queues; i++) { | |
2206 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
2207 | if (!set->tags[i]) | |
2208 | goto out_unwind; | |
2209 | } | |
2210 | ||
2211 | return 0; | |
2212 | ||
2213 | out_unwind: | |
2214 | while (--i >= 0) | |
2215 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2216 | ||
a5164405 JA |
2217 | return -ENOMEM; |
2218 | } | |
2219 | ||
2220 | /* | |
2221 | * Allocate the request maps associated with this tag_set. Note that this | |
2222 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
2223 | * will be updated to reflect the allocated depth. | |
2224 | */ | |
2225 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
2226 | { | |
2227 | unsigned int depth; | |
2228 | int err; | |
2229 | ||
2230 | depth = set->queue_depth; | |
2231 | do { | |
2232 | err = __blk_mq_alloc_rq_maps(set); | |
2233 | if (!err) | |
2234 | break; | |
2235 | ||
2236 | set->queue_depth >>= 1; | |
2237 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
2238 | err = -ENOMEM; | |
2239 | break; | |
2240 | } | |
2241 | } while (set->queue_depth); | |
2242 | ||
2243 | if (!set->queue_depth || err) { | |
2244 | pr_err("blk-mq: failed to allocate request map\n"); | |
2245 | return -ENOMEM; | |
2246 | } | |
2247 | ||
2248 | if (depth != set->queue_depth) | |
2249 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2250 | depth, set->queue_depth); | |
2251 | ||
2252 | return 0; | |
2253 | } | |
2254 | ||
f26cdc85 KB |
2255 | struct cpumask *blk_mq_tags_cpumask(struct blk_mq_tags *tags) |
2256 | { | |
2257 | return tags->cpumask; | |
2258 | } | |
2259 | EXPORT_SYMBOL_GPL(blk_mq_tags_cpumask); | |
2260 | ||
a4391c64 JA |
2261 | /* |
2262 | * Alloc a tag set to be associated with one or more request queues. | |
2263 | * May fail with EINVAL for various error conditions. May adjust the | |
2264 | * requested depth down, if if it too large. In that case, the set | |
2265 | * value will be stored in set->queue_depth. | |
2266 | */ | |
24d2f903 CH |
2267 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2268 | { | |
205fb5f5 BVA |
2269 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
2270 | ||
24d2f903 CH |
2271 | if (!set->nr_hw_queues) |
2272 | return -EINVAL; | |
a4391c64 | 2273 | if (!set->queue_depth) |
24d2f903 CH |
2274 | return -EINVAL; |
2275 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2276 | return -EINVAL; | |
2277 | ||
f9018ac9 | 2278 | if (!set->ops->queue_rq || !set->ops->map_queue) |
24d2f903 CH |
2279 | return -EINVAL; |
2280 | ||
a4391c64 JA |
2281 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2282 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2283 | BLK_MQ_MAX_DEPTH); | |
2284 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2285 | } | |
24d2f903 | 2286 | |
6637fadf SL |
2287 | /* |
2288 | * If a crashdump is active, then we are potentially in a very | |
2289 | * memory constrained environment. Limit us to 1 queue and | |
2290 | * 64 tags to prevent using too much memory. | |
2291 | */ | |
2292 | if (is_kdump_kernel()) { | |
2293 | set->nr_hw_queues = 1; | |
2294 | set->queue_depth = min(64U, set->queue_depth); | |
2295 | } | |
868f2f0b KB |
2296 | /* |
2297 | * There is no use for more h/w queues than cpus. | |
2298 | */ | |
2299 | if (set->nr_hw_queues > nr_cpu_ids) | |
2300 | set->nr_hw_queues = nr_cpu_ids; | |
6637fadf | 2301 | |
868f2f0b | 2302 | set->tags = kzalloc_node(nr_cpu_ids * sizeof(struct blk_mq_tags *), |
24d2f903 CH |
2303 | GFP_KERNEL, set->numa_node); |
2304 | if (!set->tags) | |
a5164405 | 2305 | return -ENOMEM; |
24d2f903 | 2306 | |
a5164405 JA |
2307 | if (blk_mq_alloc_rq_maps(set)) |
2308 | goto enomem; | |
24d2f903 | 2309 | |
0d2602ca JA |
2310 | mutex_init(&set->tag_list_lock); |
2311 | INIT_LIST_HEAD(&set->tag_list); | |
2312 | ||
24d2f903 | 2313 | return 0; |
a5164405 | 2314 | enomem: |
5676e7b6 RE |
2315 | kfree(set->tags); |
2316 | set->tags = NULL; | |
24d2f903 CH |
2317 | return -ENOMEM; |
2318 | } | |
2319 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2320 | ||
2321 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2322 | { | |
2323 | int i; | |
2324 | ||
868f2f0b | 2325 | for (i = 0; i < nr_cpu_ids; i++) { |
f42d79ab | 2326 | if (set->tags[i]) |
484b4061 JA |
2327 | blk_mq_free_rq_map(set, set->tags[i], i); |
2328 | } | |
2329 | ||
981bd189 | 2330 | kfree(set->tags); |
5676e7b6 | 2331 | set->tags = NULL; |
24d2f903 CH |
2332 | } |
2333 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2334 | ||
e3a2b3f9 JA |
2335 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2336 | { | |
2337 | struct blk_mq_tag_set *set = q->tag_set; | |
2338 | struct blk_mq_hw_ctx *hctx; | |
2339 | int i, ret; | |
2340 | ||
2341 | if (!set || nr > set->queue_depth) | |
2342 | return -EINVAL; | |
2343 | ||
2344 | ret = 0; | |
2345 | queue_for_each_hw_ctx(q, hctx, i) { | |
e9137d4b KB |
2346 | if (!hctx->tags) |
2347 | continue; | |
e3a2b3f9 JA |
2348 | ret = blk_mq_tag_update_depth(hctx->tags, nr); |
2349 | if (ret) | |
2350 | break; | |
2351 | } | |
2352 | ||
2353 | if (!ret) | |
2354 | q->nr_requests = nr; | |
2355 | ||
2356 | return ret; | |
2357 | } | |
2358 | ||
868f2f0b KB |
2359 | void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues) |
2360 | { | |
2361 | struct request_queue *q; | |
2362 | ||
2363 | if (nr_hw_queues > nr_cpu_ids) | |
2364 | nr_hw_queues = nr_cpu_ids; | |
2365 | if (nr_hw_queues < 1 || nr_hw_queues == set->nr_hw_queues) | |
2366 | return; | |
2367 | ||
2368 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
2369 | blk_mq_freeze_queue(q); | |
2370 | ||
2371 | set->nr_hw_queues = nr_hw_queues; | |
2372 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
2373 | blk_mq_realloc_hw_ctxs(set, q); | |
2374 | ||
2375 | if (q->nr_hw_queues > 1) | |
2376 | blk_queue_make_request(q, blk_mq_make_request); | |
2377 | else | |
2378 | blk_queue_make_request(q, blk_sq_make_request); | |
2379 | ||
2380 | blk_mq_queue_reinit(q, cpu_online_mask); | |
2381 | } | |
2382 | ||
2383 | list_for_each_entry(q, &set->tag_list, tag_set_list) | |
2384 | blk_mq_unfreeze_queue(q); | |
2385 | } | |
2386 | EXPORT_SYMBOL_GPL(blk_mq_update_nr_hw_queues); | |
2387 | ||
676141e4 JA |
2388 | void blk_mq_disable_hotplug(void) |
2389 | { | |
2390 | mutex_lock(&all_q_mutex); | |
2391 | } | |
2392 | ||
2393 | void blk_mq_enable_hotplug(void) | |
2394 | { | |
2395 | mutex_unlock(&all_q_mutex); | |
2396 | } | |
2397 | ||
320ae51f JA |
2398 | static int __init blk_mq_init(void) |
2399 | { | |
320ae51f JA |
2400 | blk_mq_cpu_init(); |
2401 | ||
add703fd | 2402 | hotcpu_notifier(blk_mq_queue_reinit_notify, 0); |
320ae51f JA |
2403 | |
2404 | return 0; | |
2405 | } | |
2406 | subsys_initcall(blk_mq_init); |