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> | |
12 | #include <linux/mm.h> | |
13 | #include <linux/init.h> | |
14 | #include <linux/slab.h> | |
15 | #include <linux/workqueue.h> | |
16 | #include <linux/smp.h> | |
17 | #include <linux/llist.h> | |
18 | #include <linux/list_sort.h> | |
19 | #include <linux/cpu.h> | |
20 | #include <linux/cache.h> | |
21 | #include <linux/sched/sysctl.h> | |
22 | #include <linux/delay.h> | |
aedcd72f | 23 | #include <linux/crash_dump.h> |
320ae51f JA |
24 | |
25 | #include <trace/events/block.h> | |
26 | ||
27 | #include <linux/blk-mq.h> | |
28 | #include "blk.h" | |
29 | #include "blk-mq.h" | |
30 | #include "blk-mq-tag.h" | |
31 | ||
32 | static DEFINE_MUTEX(all_q_mutex); | |
33 | static LIST_HEAD(all_q_list); | |
34 | ||
35 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx); | |
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 | { | |
42 | unsigned int i; | |
43 | ||
569fd0ce | 44 | for (i = 0; i < hctx->ctx_map.size; i++) |
1429d7c9 | 45 | if (hctx->ctx_map.map[i].word) |
320ae51f JA |
46 | return true; |
47 | ||
48 | return false; | |
49 | } | |
50 | ||
1429d7c9 JA |
51 | static inline struct blk_align_bitmap *get_bm(struct blk_mq_hw_ctx *hctx, |
52 | struct blk_mq_ctx *ctx) | |
53 | { | |
54 | return &hctx->ctx_map.map[ctx->index_hw / hctx->ctx_map.bits_per_word]; | |
55 | } | |
56 | ||
57 | #define CTX_TO_BIT(hctx, ctx) \ | |
58 | ((ctx)->index_hw & ((hctx)->ctx_map.bits_per_word - 1)) | |
59 | ||
320ae51f JA |
60 | /* |
61 | * Mark this ctx as having pending work in this hardware queue | |
62 | */ | |
63 | static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, | |
64 | struct blk_mq_ctx *ctx) | |
65 | { | |
1429d7c9 JA |
66 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); |
67 | ||
68 | if (!test_bit(CTX_TO_BIT(hctx, ctx), &bm->word)) | |
69 | set_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
70 | } | |
71 | ||
72 | static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, | |
73 | struct blk_mq_ctx *ctx) | |
74 | { | |
75 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); | |
76 | ||
77 | clear_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
320ae51f JA |
78 | } |
79 | ||
bfd343aa | 80 | static int blk_mq_queue_enter(struct request_queue *q, gfp_t gfp) |
320ae51f | 81 | { |
add703fd TH |
82 | while (true) { |
83 | int ret; | |
320ae51f | 84 | |
add703fd TH |
85 | if (percpu_ref_tryget_live(&q->mq_usage_counter)) |
86 | return 0; | |
320ae51f | 87 | |
bfd343aa KB |
88 | if (!(gfp & __GFP_WAIT)) |
89 | return -EBUSY; | |
90 | ||
add703fd TH |
91 | ret = wait_event_interruptible(q->mq_freeze_wq, |
92 | !q->mq_freeze_depth || blk_queue_dying(q)); | |
93 | if (blk_queue_dying(q)) | |
94 | return -ENODEV; | |
95 | if (ret) | |
96 | return ret; | |
97 | } | |
320ae51f JA |
98 | } |
99 | ||
100 | static void blk_mq_queue_exit(struct request_queue *q) | |
101 | { | |
add703fd TH |
102 | percpu_ref_put(&q->mq_usage_counter); |
103 | } | |
104 | ||
105 | static void blk_mq_usage_counter_release(struct percpu_ref *ref) | |
106 | { | |
107 | struct request_queue *q = | |
108 | container_of(ref, struct request_queue, mq_usage_counter); | |
109 | ||
110 | wake_up_all(&q->mq_freeze_wq); | |
320ae51f JA |
111 | } |
112 | ||
b4c6a028 | 113 | void blk_mq_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 114 | { |
cddd5d17 TH |
115 | bool freeze; |
116 | ||
72d6f02a | 117 | spin_lock_irq(q->queue_lock); |
cddd5d17 | 118 | freeze = !q->mq_freeze_depth++; |
72d6f02a TH |
119 | spin_unlock_irq(q->queue_lock); |
120 | ||
cddd5d17 | 121 | if (freeze) { |
9eca8046 | 122 | percpu_ref_kill(&q->mq_usage_counter); |
b94ec296 | 123 | blk_mq_run_hw_queues(q, false); |
cddd5d17 | 124 | } |
f3af020b | 125 | } |
b4c6a028 | 126 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start); |
f3af020b TH |
127 | |
128 | static void blk_mq_freeze_queue_wait(struct request_queue *q) | |
129 | { | |
add703fd | 130 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); |
43a5e4e2 ML |
131 | } |
132 | ||
f3af020b TH |
133 | /* |
134 | * Guarantee no request is in use, so we can change any data structure of | |
135 | * the queue afterward. | |
136 | */ | |
137 | void blk_mq_freeze_queue(struct request_queue *q) | |
138 | { | |
139 | blk_mq_freeze_queue_start(q); | |
140 | blk_mq_freeze_queue_wait(q); | |
141 | } | |
c761d96b | 142 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue); |
f3af020b | 143 | |
b4c6a028 | 144 | void blk_mq_unfreeze_queue(struct request_queue *q) |
320ae51f | 145 | { |
cddd5d17 | 146 | bool wake; |
320ae51f JA |
147 | |
148 | spin_lock_irq(q->queue_lock); | |
780db207 TH |
149 | wake = !--q->mq_freeze_depth; |
150 | WARN_ON_ONCE(q->mq_freeze_depth < 0); | |
320ae51f | 151 | spin_unlock_irq(q->queue_lock); |
add703fd TH |
152 | if (wake) { |
153 | percpu_ref_reinit(&q->mq_usage_counter); | |
320ae51f | 154 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 155 | } |
320ae51f | 156 | } |
b4c6a028 | 157 | EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
320ae51f | 158 | |
aed3ea94 JA |
159 | void blk_mq_wake_waiters(struct request_queue *q) |
160 | { | |
161 | struct blk_mq_hw_ctx *hctx; | |
162 | unsigned int i; | |
163 | ||
164 | queue_for_each_hw_ctx(q, hctx, i) | |
165 | if (blk_mq_hw_queue_mapped(hctx)) | |
166 | blk_mq_tag_wakeup_all(hctx->tags, true); | |
3fd5940c KB |
167 | |
168 | /* | |
169 | * If we are called because the queue has now been marked as | |
170 | * dying, we need to ensure that processes currently waiting on | |
171 | * the queue are notified as well. | |
172 | */ | |
173 | wake_up_all(&q->mq_freeze_wq); | |
aed3ea94 JA |
174 | } |
175 | ||
320ae51f JA |
176 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) |
177 | { | |
178 | return blk_mq_has_free_tags(hctx->tags); | |
179 | } | |
180 | EXPORT_SYMBOL(blk_mq_can_queue); | |
181 | ||
94eddfbe JA |
182 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
183 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 184 | { |
94eddfbe JA |
185 | if (blk_queue_io_stat(q)) |
186 | rw_flags |= REQ_IO_STAT; | |
187 | ||
af76e555 CH |
188 | INIT_LIST_HEAD(&rq->queuelist); |
189 | /* csd/requeue_work/fifo_time is initialized before use */ | |
190 | rq->q = q; | |
320ae51f | 191 | rq->mq_ctx = ctx; |
0d2602ca | 192 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
193 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
194 | rq->cpu = -1; | |
af76e555 CH |
195 | INIT_HLIST_NODE(&rq->hash); |
196 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
197 | rq->rq_disk = NULL; |
198 | rq->part = NULL; | |
3ee32372 | 199 | rq->start_time = jiffies; |
af76e555 CH |
200 | #ifdef CONFIG_BLK_CGROUP |
201 | rq->rl = NULL; | |
0fec08b4 | 202 | set_start_time_ns(rq); |
af76e555 CH |
203 | rq->io_start_time_ns = 0; |
204 | #endif | |
205 | rq->nr_phys_segments = 0; | |
206 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
207 | rq->nr_integrity_segments = 0; | |
208 | #endif | |
af76e555 CH |
209 | rq->special = NULL; |
210 | /* tag was already set */ | |
211 | rq->errors = 0; | |
af76e555 | 212 | |
6f4a1626 TB |
213 | rq->cmd = rq->__cmd; |
214 | ||
af76e555 CH |
215 | rq->extra_len = 0; |
216 | rq->sense_len = 0; | |
217 | rq->resid_len = 0; | |
218 | rq->sense = NULL; | |
219 | ||
af76e555 | 220 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
221 | rq->timeout = 0; |
222 | ||
af76e555 CH |
223 | rq->end_io = NULL; |
224 | rq->end_io_data = NULL; | |
225 | rq->next_rq = NULL; | |
226 | ||
320ae51f JA |
227 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
228 | } | |
229 | ||
5dee8577 | 230 | static struct request * |
cb96a42c | 231 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) |
5dee8577 CH |
232 | { |
233 | struct request *rq; | |
234 | unsigned int tag; | |
235 | ||
cb96a42c | 236 | tag = blk_mq_get_tag(data); |
5dee8577 | 237 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 238 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 239 | |
cb96a42c | 240 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 241 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 242 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
243 | } |
244 | ||
245 | rq->tag = tag; | |
cb96a42c | 246 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); |
5dee8577 CH |
247 | return rq; |
248 | } | |
249 | ||
250 | return NULL; | |
251 | } | |
252 | ||
4ce01dd1 CH |
253 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp, |
254 | bool reserved) | |
320ae51f | 255 | { |
d852564f CH |
256 | struct blk_mq_ctx *ctx; |
257 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 258 | struct request *rq; |
cb96a42c | 259 | struct blk_mq_alloc_data alloc_data; |
a492f075 | 260 | int ret; |
320ae51f | 261 | |
bfd343aa | 262 | ret = blk_mq_queue_enter(q, gfp); |
a492f075 JL |
263 | if (ret) |
264 | return ERR_PTR(ret); | |
320ae51f | 265 | |
d852564f CH |
266 | ctx = blk_mq_get_ctx(q); |
267 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
268 | blk_mq_set_alloc_data(&alloc_data, q, gfp & ~__GFP_WAIT, |
269 | reserved, ctx, hctx); | |
d852564f | 270 | |
cb96a42c | 271 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
d852564f CH |
272 | if (!rq && (gfp & __GFP_WAIT)) { |
273 | __blk_mq_run_hw_queue(hctx); | |
274 | blk_mq_put_ctx(ctx); | |
275 | ||
276 | ctx = blk_mq_get_ctx(q); | |
277 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
278 | blk_mq_set_alloc_data(&alloc_data, q, gfp, reserved, ctx, |
279 | hctx); | |
280 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
281 | ctx = alloc_data.ctx; | |
d852564f CH |
282 | } |
283 | blk_mq_put_ctx(ctx); | |
c76541a9 KB |
284 | if (!rq) { |
285 | blk_mq_queue_exit(q); | |
a492f075 | 286 | return ERR_PTR(-EWOULDBLOCK); |
c76541a9 | 287 | } |
320ae51f JA |
288 | return rq; |
289 | } | |
4bb659b1 | 290 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 291 | |
320ae51f JA |
292 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
293 | struct blk_mq_ctx *ctx, struct request *rq) | |
294 | { | |
295 | const int tag = rq->tag; | |
296 | struct request_queue *q = rq->q; | |
297 | ||
0d2602ca JA |
298 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
299 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 300 | rq->cmd_flags = 0; |
0d2602ca | 301 | |
af76e555 | 302 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 303 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
320ae51f JA |
304 | blk_mq_queue_exit(q); |
305 | } | |
306 | ||
7c7f2f2b | 307 | void blk_mq_free_hctx_request(struct blk_mq_hw_ctx *hctx, struct request *rq) |
320ae51f JA |
308 | { |
309 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
320ae51f JA |
310 | |
311 | ctx->rq_completed[rq_is_sync(rq)]++; | |
320ae51f | 312 | __blk_mq_free_request(hctx, ctx, rq); |
7c7f2f2b JA |
313 | |
314 | } | |
315 | EXPORT_SYMBOL_GPL(blk_mq_free_hctx_request); | |
316 | ||
317 | void blk_mq_free_request(struct request *rq) | |
318 | { | |
319 | struct blk_mq_hw_ctx *hctx; | |
320 | struct request_queue *q = rq->q; | |
321 | ||
322 | hctx = q->mq_ops->map_queue(q, rq->mq_ctx->cpu); | |
323 | blk_mq_free_hctx_request(hctx, rq); | |
320ae51f | 324 | } |
1a3b595a | 325 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 326 | |
c8a446ad | 327 | inline void __blk_mq_end_request(struct request *rq, int error) |
320ae51f | 328 | { |
0d11e6ac ML |
329 | blk_account_io_done(rq); |
330 | ||
91b63639 | 331 | if (rq->end_io) { |
320ae51f | 332 | rq->end_io(rq, error); |
91b63639 CH |
333 | } else { |
334 | if (unlikely(blk_bidi_rq(rq))) | |
335 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 336 | blk_mq_free_request(rq); |
91b63639 | 337 | } |
320ae51f | 338 | } |
c8a446ad | 339 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 340 | |
c8a446ad | 341 | void blk_mq_end_request(struct request *rq, int error) |
63151a44 CH |
342 | { |
343 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
344 | BUG(); | |
c8a446ad | 345 | __blk_mq_end_request(rq, error); |
63151a44 | 346 | } |
c8a446ad | 347 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 348 | |
30a91cb4 | 349 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 350 | { |
3d6efbf6 | 351 | struct request *rq = data; |
320ae51f | 352 | |
30a91cb4 | 353 | rq->q->softirq_done_fn(rq); |
320ae51f | 354 | } |
320ae51f | 355 | |
ed851860 | 356 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
357 | { |
358 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 359 | bool shared = false; |
320ae51f JA |
360 | int cpu; |
361 | ||
38535201 | 362 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
363 | rq->q->softirq_done_fn(rq); |
364 | return; | |
365 | } | |
320ae51f JA |
366 | |
367 | cpu = get_cpu(); | |
38535201 CH |
368 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
369 | shared = cpus_share_cache(cpu, ctx->cpu); | |
370 | ||
371 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 372 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
373 | rq->csd.info = rq; |
374 | rq->csd.flags = 0; | |
c46fff2a | 375 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 376 | } else { |
30a91cb4 | 377 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 378 | } |
320ae51f JA |
379 | put_cpu(); |
380 | } | |
30a91cb4 | 381 | |
ed851860 JA |
382 | void __blk_mq_complete_request(struct request *rq) |
383 | { | |
384 | struct request_queue *q = rq->q; | |
385 | ||
386 | if (!q->softirq_done_fn) | |
c8a446ad | 387 | blk_mq_end_request(rq, rq->errors); |
ed851860 JA |
388 | else |
389 | blk_mq_ipi_complete_request(rq); | |
390 | } | |
391 | ||
30a91cb4 CH |
392 | /** |
393 | * blk_mq_complete_request - end I/O on a request | |
394 | * @rq: the request being processed | |
395 | * | |
396 | * Description: | |
397 | * Ends all I/O on a request. It does not handle partial completions. | |
398 | * The actual completion happens out-of-order, through a IPI handler. | |
399 | **/ | |
400 | void blk_mq_complete_request(struct request *rq) | |
401 | { | |
95f09684 JA |
402 | struct request_queue *q = rq->q; |
403 | ||
404 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 405 | return; |
ed851860 JA |
406 | if (!blk_mark_rq_complete(rq)) |
407 | __blk_mq_complete_request(rq); | |
30a91cb4 CH |
408 | } |
409 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 410 | |
973c0191 KB |
411 | int blk_mq_request_started(struct request *rq) |
412 | { | |
413 | return test_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
414 | } | |
415 | EXPORT_SYMBOL_GPL(blk_mq_request_started); | |
416 | ||
e2490073 | 417 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
418 | { |
419 | struct request_queue *q = rq->q; | |
420 | ||
421 | trace_block_rq_issue(q, rq); | |
422 | ||
742ee69b | 423 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
424 | if (unlikely(blk_bidi_rq(rq))) |
425 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 426 | |
2b8393b4 | 427 | blk_add_timer(rq); |
87ee7b11 | 428 | |
538b7534 JA |
429 | /* |
430 | * Ensure that ->deadline is visible before set the started | |
431 | * flag and clear the completed flag. | |
432 | */ | |
433 | smp_mb__before_atomic(); | |
434 | ||
87ee7b11 JA |
435 | /* |
436 | * Mark us as started and clear complete. Complete might have been | |
437 | * set if requeue raced with timeout, which then marked it as | |
438 | * complete. So be sure to clear complete again when we start | |
439 | * the request, otherwise we'll ignore the completion event. | |
440 | */ | |
4b570521 JA |
441 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
442 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
443 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
444 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
445 | |
446 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
447 | /* | |
448 | * Make sure space for the drain appears. We know we can do | |
449 | * this because max_hw_segments has been adjusted to be one | |
450 | * fewer than the device can handle. | |
451 | */ | |
452 | rq->nr_phys_segments++; | |
453 | } | |
320ae51f | 454 | } |
e2490073 | 455 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 456 | |
ed0791b2 | 457 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
458 | { |
459 | struct request_queue *q = rq->q; | |
460 | ||
461 | trace_block_rq_requeue(q, rq); | |
49f5baa5 | 462 | |
e2490073 CH |
463 | if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
464 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
465 | rq->nr_phys_segments--; | |
466 | } | |
320ae51f JA |
467 | } |
468 | ||
ed0791b2 CH |
469 | void blk_mq_requeue_request(struct request *rq) |
470 | { | |
ed0791b2 | 471 | __blk_mq_requeue_request(rq); |
ed0791b2 | 472 | |
ed0791b2 | 473 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 474 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
475 | } |
476 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
477 | ||
6fca6a61 CH |
478 | static void blk_mq_requeue_work(struct work_struct *work) |
479 | { | |
480 | struct request_queue *q = | |
481 | container_of(work, struct request_queue, requeue_work); | |
482 | LIST_HEAD(rq_list); | |
483 | struct request *rq, *next; | |
484 | unsigned long flags; | |
485 | ||
486 | spin_lock_irqsave(&q->requeue_lock, flags); | |
487 | list_splice_init(&q->requeue_list, &rq_list); | |
488 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
489 | ||
490 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
491 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
492 | continue; | |
493 | ||
494 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
495 | list_del_init(&rq->queuelist); | |
496 | blk_mq_insert_request(rq, true, false, false); | |
497 | } | |
498 | ||
499 | while (!list_empty(&rq_list)) { | |
500 | rq = list_entry(rq_list.next, struct request, queuelist); | |
501 | list_del_init(&rq->queuelist); | |
502 | blk_mq_insert_request(rq, false, false, false); | |
503 | } | |
504 | ||
8b957415 JA |
505 | /* |
506 | * Use the start variant of queue running here, so that running | |
507 | * the requeue work will kick stopped queues. | |
508 | */ | |
509 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
510 | } |
511 | ||
512 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
513 | { | |
514 | struct request_queue *q = rq->q; | |
515 | unsigned long flags; | |
516 | ||
517 | /* | |
518 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
519 | * request head insertation from the workqueue. | |
520 | */ | |
521 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
522 | ||
523 | spin_lock_irqsave(&q->requeue_lock, flags); | |
524 | if (at_head) { | |
525 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
526 | list_add(&rq->queuelist, &q->requeue_list); | |
527 | } else { | |
528 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
529 | } | |
530 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
531 | } | |
532 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
533 | ||
c68ed59f KB |
534 | void blk_mq_cancel_requeue_work(struct request_queue *q) |
535 | { | |
536 | cancel_work_sync(&q->requeue_work); | |
537 | } | |
538 | EXPORT_SYMBOL_GPL(blk_mq_cancel_requeue_work); | |
539 | ||
6fca6a61 CH |
540 | void blk_mq_kick_requeue_list(struct request_queue *q) |
541 | { | |
542 | kblockd_schedule_work(&q->requeue_work); | |
543 | } | |
544 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
545 | ||
1885b24d JA |
546 | void blk_mq_abort_requeue_list(struct request_queue *q) |
547 | { | |
548 | unsigned long flags; | |
549 | LIST_HEAD(rq_list); | |
550 | ||
551 | spin_lock_irqsave(&q->requeue_lock, flags); | |
552 | list_splice_init(&q->requeue_list, &rq_list); | |
553 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
554 | ||
555 | while (!list_empty(&rq_list)) { | |
556 | struct request *rq; | |
557 | ||
558 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
559 | list_del_init(&rq->queuelist); | |
560 | rq->errors = -EIO; | |
561 | blk_mq_end_request(rq, rq->errors); | |
562 | } | |
563 | } | |
564 | EXPORT_SYMBOL(blk_mq_abort_requeue_list); | |
565 | ||
7c94e1c1 ML |
566 | static inline bool is_flush_request(struct request *rq, |
567 | struct blk_flush_queue *fq, unsigned int tag) | |
24d2f903 | 568 | { |
0e62f51f | 569 | return ((rq->cmd_flags & REQ_FLUSH_SEQ) && |
7c94e1c1 | 570 | fq->flush_rq->tag == tag); |
0e62f51f JA |
571 | } |
572 | ||
573 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) | |
574 | { | |
575 | struct request *rq = tags->rqs[tag]; | |
e97c293c ML |
576 | /* mq_ctx of flush rq is always cloned from the corresponding req */ |
577 | struct blk_flush_queue *fq = blk_get_flush_queue(rq->q, rq->mq_ctx); | |
22302375 | 578 | |
7c94e1c1 | 579 | if (!is_flush_request(rq, fq, tag)) |
0e62f51f | 580 | return rq; |
22302375 | 581 | |
7c94e1c1 | 582 | return fq->flush_rq; |
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 | */ | |
637 | if (unlikely(blk_queue_dying(rq->q))) { | |
638 | rq->errors = -EIO; | |
639 | blk_mq_complete_request(rq); | |
640 | } | |
46f92d42 | 641 | return; |
eb130dbf | 642 | } |
5b3f25fc KB |
643 | if (rq->cmd_flags & REQ_NO_TIMEOUT) |
644 | return; | |
87ee7b11 | 645 | |
46f92d42 CH |
646 | if (time_after_eq(jiffies, rq->deadline)) { |
647 | if (!blk_mark_rq_complete(rq)) | |
0152fb6b | 648 | blk_mq_rq_timed_out(rq, reserved); |
46f92d42 CH |
649 | } else if (!data->next_set || time_after(data->next, rq->deadline)) { |
650 | data->next = rq->deadline; | |
651 | data->next_set = 1; | |
652 | } | |
87ee7b11 JA |
653 | } |
654 | ||
81481eb4 | 655 | static void blk_mq_rq_timer(unsigned long priv) |
320ae51f | 656 | { |
81481eb4 CH |
657 | struct request_queue *q = (struct request_queue *)priv; |
658 | struct blk_mq_timeout_data data = { | |
659 | .next = 0, | |
660 | .next_set = 0, | |
661 | }; | |
320ae51f | 662 | struct blk_mq_hw_ctx *hctx; |
81481eb4 | 663 | int i; |
320ae51f | 664 | |
484b4061 JA |
665 | queue_for_each_hw_ctx(q, hctx, i) { |
666 | /* | |
667 | * If not software queues are currently mapped to this | |
668 | * hardware queue, there's nothing to check | |
669 | */ | |
19c66e59 | 670 | if (!blk_mq_hw_queue_mapped(hctx)) |
484b4061 JA |
671 | continue; |
672 | ||
81481eb4 | 673 | blk_mq_tag_busy_iter(hctx, blk_mq_check_expired, &data); |
484b4061 | 674 | } |
320ae51f | 675 | |
81481eb4 CH |
676 | if (data.next_set) { |
677 | data.next = blk_rq_timeout(round_jiffies_up(data.next)); | |
678 | mod_timer(&q->timeout, data.next); | |
0d2602ca | 679 | } else { |
f054b56c ML |
680 | queue_for_each_hw_ctx(q, hctx, i) { |
681 | /* the hctx may be unmapped, so check it here */ | |
682 | if (blk_mq_hw_queue_mapped(hctx)) | |
683 | blk_mq_tag_idle(hctx); | |
684 | } | |
0d2602ca | 685 | } |
320ae51f JA |
686 | } |
687 | ||
688 | /* | |
689 | * Reverse check our software queue for entries that we could potentially | |
690 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
691 | * too much time checking for merges. | |
692 | */ | |
693 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
694 | struct blk_mq_ctx *ctx, struct bio *bio) | |
695 | { | |
696 | struct request *rq; | |
697 | int checked = 8; | |
698 | ||
699 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
700 | int el_ret; | |
701 | ||
702 | if (!checked--) | |
703 | break; | |
704 | ||
705 | if (!blk_rq_merge_ok(rq, bio)) | |
706 | continue; | |
707 | ||
708 | el_ret = blk_try_merge(rq, bio); | |
709 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
710 | if (bio_attempt_back_merge(q, rq, bio)) { | |
711 | ctx->rq_merged++; | |
712 | return true; | |
713 | } | |
714 | break; | |
715 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
716 | if (bio_attempt_front_merge(q, rq, bio)) { | |
717 | ctx->rq_merged++; | |
718 | return true; | |
719 | } | |
720 | break; | |
721 | } | |
722 | } | |
723 | ||
724 | return false; | |
725 | } | |
726 | ||
1429d7c9 JA |
727 | /* |
728 | * Process software queues that have been marked busy, splicing them | |
729 | * to the for-dispatch | |
730 | */ | |
731 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
732 | { | |
733 | struct blk_mq_ctx *ctx; | |
734 | int i; | |
735 | ||
569fd0ce | 736 | for (i = 0; i < hctx->ctx_map.size; i++) { |
1429d7c9 JA |
737 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; |
738 | unsigned int off, bit; | |
739 | ||
740 | if (!bm->word) | |
741 | continue; | |
742 | ||
743 | bit = 0; | |
744 | off = i * hctx->ctx_map.bits_per_word; | |
745 | do { | |
746 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
747 | if (bit >= bm->depth) | |
748 | break; | |
749 | ||
750 | ctx = hctx->ctxs[bit + off]; | |
751 | clear_bit(bit, &bm->word); | |
752 | spin_lock(&ctx->lock); | |
753 | list_splice_tail_init(&ctx->rq_list, list); | |
754 | spin_unlock(&ctx->lock); | |
755 | ||
756 | bit++; | |
757 | } while (1); | |
758 | } | |
759 | } | |
760 | ||
320ae51f JA |
761 | /* |
762 | * Run this hardware queue, pulling any software queues mapped to it in. | |
763 | * Note that this function currently has various problems around ordering | |
764 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
765 | * items on the hctx->dispatch list. Ignore that for now. | |
766 | */ | |
767 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
768 | { | |
769 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
770 | struct request *rq; |
771 | LIST_HEAD(rq_list); | |
74c45052 JA |
772 | LIST_HEAD(driver_list); |
773 | struct list_head *dptr; | |
1429d7c9 | 774 | int queued; |
320ae51f | 775 | |
fd1270d5 | 776 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 777 | |
5d12f905 | 778 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
779 | return; |
780 | ||
781 | hctx->run++; | |
782 | ||
783 | /* | |
784 | * Touch any software queue that has pending entries. | |
785 | */ | |
1429d7c9 | 786 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
787 | |
788 | /* | |
789 | * If we have previous entries on our dispatch list, grab them | |
790 | * and stuff them at the front for more fair dispatch. | |
791 | */ | |
792 | if (!list_empty_careful(&hctx->dispatch)) { | |
793 | spin_lock(&hctx->lock); | |
794 | if (!list_empty(&hctx->dispatch)) | |
795 | list_splice_init(&hctx->dispatch, &rq_list); | |
796 | spin_unlock(&hctx->lock); | |
797 | } | |
798 | ||
74c45052 JA |
799 | /* |
800 | * Start off with dptr being NULL, so we start the first request | |
801 | * immediately, even if we have more pending. | |
802 | */ | |
803 | dptr = NULL; | |
804 | ||
320ae51f JA |
805 | /* |
806 | * Now process all the entries, sending them to the driver. | |
807 | */ | |
1429d7c9 | 808 | queued = 0; |
320ae51f | 809 | while (!list_empty(&rq_list)) { |
74c45052 | 810 | struct blk_mq_queue_data bd; |
320ae51f JA |
811 | int ret; |
812 | ||
813 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
814 | list_del_init(&rq->queuelist); | |
320ae51f | 815 | |
74c45052 JA |
816 | bd.rq = rq; |
817 | bd.list = dptr; | |
818 | bd.last = list_empty(&rq_list); | |
819 | ||
820 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
320ae51f JA |
821 | switch (ret) { |
822 | case BLK_MQ_RQ_QUEUE_OK: | |
823 | queued++; | |
824 | continue; | |
825 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 826 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 827 | __blk_mq_requeue_request(rq); |
320ae51f JA |
828 | break; |
829 | default: | |
830 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 831 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 832 | rq->errors = -EIO; |
c8a446ad | 833 | blk_mq_end_request(rq, rq->errors); |
320ae51f JA |
834 | break; |
835 | } | |
836 | ||
837 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
838 | break; | |
74c45052 JA |
839 | |
840 | /* | |
841 | * We've done the first request. If we have more than 1 | |
842 | * left in the list, set dptr to defer issue. | |
843 | */ | |
844 | if (!dptr && rq_list.next != rq_list.prev) | |
845 | dptr = &driver_list; | |
320ae51f JA |
846 | } |
847 | ||
848 | if (!queued) | |
849 | hctx->dispatched[0]++; | |
850 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
851 | hctx->dispatched[ilog2(queued) + 1]++; | |
852 | ||
853 | /* | |
854 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
855 | * that is where we will continue on next queue run. | |
856 | */ | |
857 | if (!list_empty(&rq_list)) { | |
858 | spin_lock(&hctx->lock); | |
859 | list_splice(&rq_list, &hctx->dispatch); | |
860 | spin_unlock(&hctx->lock); | |
9ba52e58 SL |
861 | /* |
862 | * the queue is expected stopped with BLK_MQ_RQ_QUEUE_BUSY, but | |
863 | * it's possible the queue is stopped and restarted again | |
864 | * before this. Queue restart will dispatch requests. And since | |
865 | * requests in rq_list aren't added into hctx->dispatch yet, | |
866 | * the requests in rq_list might get lost. | |
867 | * | |
868 | * blk_mq_run_hw_queue() already checks the STOPPED bit | |
869 | **/ | |
870 | blk_mq_run_hw_queue(hctx, true); | |
320ae51f JA |
871 | } |
872 | } | |
873 | ||
506e931f JA |
874 | /* |
875 | * It'd be great if the workqueue API had a way to pass | |
876 | * in a mask and had some smarts for more clever placement. | |
877 | * For now we just round-robin here, switching for every | |
878 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
879 | */ | |
880 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
881 | { | |
b657d7e6 CH |
882 | if (hctx->queue->nr_hw_queues == 1) |
883 | return WORK_CPU_UNBOUND; | |
506e931f JA |
884 | |
885 | if (--hctx->next_cpu_batch <= 0) { | |
b657d7e6 | 886 | int cpu = hctx->next_cpu, next_cpu; |
506e931f JA |
887 | |
888 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
889 | if (next_cpu >= nr_cpu_ids) | |
890 | next_cpu = cpumask_first(hctx->cpumask); | |
891 | ||
892 | hctx->next_cpu = next_cpu; | |
893 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
b657d7e6 CH |
894 | |
895 | return cpu; | |
506e931f JA |
896 | } |
897 | ||
b657d7e6 | 898 | return hctx->next_cpu; |
506e931f JA |
899 | } |
900 | ||
320ae51f JA |
901 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
902 | { | |
19c66e59 ML |
903 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state) || |
904 | !blk_mq_hw_queue_mapped(hctx))) | |
320ae51f JA |
905 | return; |
906 | ||
398205b8 | 907 | if (!async) { |
2a90d4aa PB |
908 | int cpu = get_cpu(); |
909 | if (cpumask_test_cpu(cpu, hctx->cpumask)) { | |
398205b8 | 910 | __blk_mq_run_hw_queue(hctx); |
2a90d4aa | 911 | put_cpu(); |
398205b8 PB |
912 | return; |
913 | } | |
e4043dcf | 914 | |
2a90d4aa | 915 | put_cpu(); |
e4043dcf | 916 | } |
398205b8 | 917 | |
b657d7e6 CH |
918 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
919 | &hctx->run_work, 0); | |
320ae51f JA |
920 | } |
921 | ||
b94ec296 | 922 | void blk_mq_run_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
923 | { |
924 | struct blk_mq_hw_ctx *hctx; | |
925 | int i; | |
926 | ||
927 | queue_for_each_hw_ctx(q, hctx, i) { | |
928 | if ((!blk_mq_hctx_has_pending(hctx) && | |
929 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 930 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
931 | continue; |
932 | ||
b94ec296 | 933 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
934 | } |
935 | } | |
b94ec296 | 936 | EXPORT_SYMBOL(blk_mq_run_hw_queues); |
320ae51f JA |
937 | |
938 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
939 | { | |
70f4db63 CH |
940 | cancel_delayed_work(&hctx->run_work); |
941 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
942 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
943 | } | |
944 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
945 | ||
280d45f6 CH |
946 | void blk_mq_stop_hw_queues(struct request_queue *q) |
947 | { | |
948 | struct blk_mq_hw_ctx *hctx; | |
949 | int i; | |
950 | ||
951 | queue_for_each_hw_ctx(q, hctx, i) | |
952 | blk_mq_stop_hw_queue(hctx); | |
953 | } | |
954 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
955 | ||
320ae51f JA |
956 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
957 | { | |
958 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 959 | |
0ffbce80 | 960 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
961 | } |
962 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
963 | ||
2f268556 CH |
964 | void blk_mq_start_hw_queues(struct request_queue *q) |
965 | { | |
966 | struct blk_mq_hw_ctx *hctx; | |
967 | int i; | |
968 | ||
969 | queue_for_each_hw_ctx(q, hctx, i) | |
970 | blk_mq_start_hw_queue(hctx); | |
971 | } | |
972 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
973 | ||
1b4a3258 | 974 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
975 | { |
976 | struct blk_mq_hw_ctx *hctx; | |
977 | int i; | |
978 | ||
979 | queue_for_each_hw_ctx(q, hctx, i) { | |
980 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
981 | continue; | |
982 | ||
983 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
1b4a3258 | 984 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
985 | } |
986 | } | |
987 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
988 | ||
70f4db63 | 989 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
990 | { |
991 | struct blk_mq_hw_ctx *hctx; | |
992 | ||
70f4db63 | 993 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 994 | |
320ae51f JA |
995 | __blk_mq_run_hw_queue(hctx); |
996 | } | |
997 | ||
70f4db63 CH |
998 | static void blk_mq_delay_work_fn(struct work_struct *work) |
999 | { | |
1000 | struct blk_mq_hw_ctx *hctx; | |
1001 | ||
1002 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
1003 | ||
1004 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
1005 | __blk_mq_run_hw_queue(hctx); | |
1006 | } | |
1007 | ||
1008 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
1009 | { | |
19c66e59 ML |
1010 | if (unlikely(!blk_mq_hw_queue_mapped(hctx))) |
1011 | return; | |
70f4db63 | 1012 | |
b657d7e6 CH |
1013 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
1014 | &hctx->delay_work, msecs_to_jiffies(msecs)); | |
70f4db63 CH |
1015 | } |
1016 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
1017 | ||
320ae51f | 1018 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
72a0a36e | 1019 | struct request *rq, bool at_head) |
320ae51f JA |
1020 | { |
1021 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
1022 | ||
01b983c9 JA |
1023 | trace_block_rq_insert(hctx->queue, rq); |
1024 | ||
72a0a36e CH |
1025 | if (at_head) |
1026 | list_add(&rq->queuelist, &ctx->rq_list); | |
1027 | else | |
1028 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
4bb659b1 | 1029 | |
320ae51f | 1030 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
1031 | } |
1032 | ||
eeabc850 CH |
1033 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
1034 | bool async) | |
320ae51f | 1035 | { |
eeabc850 | 1036 | struct request_queue *q = rq->q; |
320ae51f | 1037 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
1038 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
1039 | ||
1040 | current_ctx = blk_mq_get_ctx(q); | |
1041 | if (!cpu_online(ctx->cpu)) | |
1042 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 1043 | |
320ae51f JA |
1044 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
1045 | ||
a57a178a CH |
1046 | spin_lock(&ctx->lock); |
1047 | __blk_mq_insert_request(hctx, rq, at_head); | |
1048 | spin_unlock(&ctx->lock); | |
320ae51f | 1049 | |
320ae51f JA |
1050 | if (run_queue) |
1051 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
1052 | |
1053 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
1054 | } |
1055 | ||
1056 | static void blk_mq_insert_requests(struct request_queue *q, | |
1057 | struct blk_mq_ctx *ctx, | |
1058 | struct list_head *list, | |
1059 | int depth, | |
1060 | bool from_schedule) | |
1061 | ||
1062 | { | |
1063 | struct blk_mq_hw_ctx *hctx; | |
1064 | struct blk_mq_ctx *current_ctx; | |
1065 | ||
1066 | trace_block_unplug(q, depth, !from_schedule); | |
1067 | ||
1068 | current_ctx = blk_mq_get_ctx(q); | |
1069 | ||
1070 | if (!cpu_online(ctx->cpu)) | |
1071 | ctx = current_ctx; | |
1072 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1073 | ||
1074 | /* | |
1075 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
1076 | * offline now | |
1077 | */ | |
1078 | spin_lock(&ctx->lock); | |
1079 | while (!list_empty(list)) { | |
1080 | struct request *rq; | |
1081 | ||
1082 | rq = list_first_entry(list, struct request, queuelist); | |
1083 | list_del_init(&rq->queuelist); | |
1084 | rq->mq_ctx = ctx; | |
72a0a36e | 1085 | __blk_mq_insert_request(hctx, rq, false); |
320ae51f JA |
1086 | } |
1087 | spin_unlock(&ctx->lock); | |
1088 | ||
320ae51f | 1089 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 1090 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
1091 | } |
1092 | ||
1093 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1094 | { | |
1095 | struct request *rqa = container_of(a, struct request, queuelist); | |
1096 | struct request *rqb = container_of(b, struct request, queuelist); | |
1097 | ||
1098 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1099 | (rqa->mq_ctx == rqb->mq_ctx && | |
1100 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1101 | } | |
1102 | ||
1103 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1104 | { | |
1105 | struct blk_mq_ctx *this_ctx; | |
1106 | struct request_queue *this_q; | |
1107 | struct request *rq; | |
1108 | LIST_HEAD(list); | |
1109 | LIST_HEAD(ctx_list); | |
1110 | unsigned int depth; | |
1111 | ||
1112 | list_splice_init(&plug->mq_list, &list); | |
1113 | ||
1114 | list_sort(NULL, &list, plug_ctx_cmp); | |
1115 | ||
1116 | this_q = NULL; | |
1117 | this_ctx = NULL; | |
1118 | depth = 0; | |
1119 | ||
1120 | while (!list_empty(&list)) { | |
1121 | rq = list_entry_rq(list.next); | |
1122 | list_del_init(&rq->queuelist); | |
1123 | BUG_ON(!rq->q); | |
1124 | if (rq->mq_ctx != this_ctx) { | |
1125 | if (this_ctx) { | |
1126 | blk_mq_insert_requests(this_q, this_ctx, | |
1127 | &ctx_list, depth, | |
1128 | from_schedule); | |
1129 | } | |
1130 | ||
1131 | this_ctx = rq->mq_ctx; | |
1132 | this_q = rq->q; | |
1133 | depth = 0; | |
1134 | } | |
1135 | ||
1136 | depth++; | |
1137 | list_add_tail(&rq->queuelist, &ctx_list); | |
1138 | } | |
1139 | ||
1140 | /* | |
1141 | * If 'this_ctx' is set, we know we have entries to complete | |
1142 | * on 'ctx_list'. Do those. | |
1143 | */ | |
1144 | if (this_ctx) { | |
1145 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1146 | from_schedule); | |
1147 | } | |
1148 | } | |
1149 | ||
1150 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1151 | { | |
1152 | init_request_from_bio(rq, bio); | |
4b570521 | 1153 | |
3ee32372 | 1154 | if (blk_do_io_stat(rq)) |
4b570521 | 1155 | blk_account_io_start(rq, 1); |
320ae51f JA |
1156 | } |
1157 | ||
274a5843 JA |
1158 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1159 | { | |
1160 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1161 | !blk_queue_nomerges(hctx->queue); | |
1162 | } | |
1163 | ||
07068d5b JA |
1164 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1165 | struct blk_mq_ctx *ctx, | |
1166 | struct request *rq, struct bio *bio) | |
320ae51f | 1167 | { |
274a5843 | 1168 | if (!hctx_allow_merges(hctx)) { |
07068d5b JA |
1169 | blk_mq_bio_to_request(rq, bio); |
1170 | spin_lock(&ctx->lock); | |
1171 | insert_rq: | |
1172 | __blk_mq_insert_request(hctx, rq, false); | |
1173 | spin_unlock(&ctx->lock); | |
1174 | return false; | |
1175 | } else { | |
274a5843 JA |
1176 | struct request_queue *q = hctx->queue; |
1177 | ||
07068d5b JA |
1178 | spin_lock(&ctx->lock); |
1179 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1180 | blk_mq_bio_to_request(rq, bio); | |
1181 | goto insert_rq; | |
1182 | } | |
320ae51f | 1183 | |
07068d5b JA |
1184 | spin_unlock(&ctx->lock); |
1185 | __blk_mq_free_request(hctx, ctx, rq); | |
1186 | return true; | |
14ec77f3 | 1187 | } |
07068d5b | 1188 | } |
14ec77f3 | 1189 | |
07068d5b JA |
1190 | struct blk_map_ctx { |
1191 | struct blk_mq_hw_ctx *hctx; | |
1192 | struct blk_mq_ctx *ctx; | |
1193 | }; | |
1194 | ||
1195 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1196 | struct bio *bio, | |
1197 | struct blk_map_ctx *data) | |
1198 | { | |
1199 | struct blk_mq_hw_ctx *hctx; | |
1200 | struct blk_mq_ctx *ctx; | |
1201 | struct request *rq; | |
1202 | int rw = bio_data_dir(bio); | |
cb96a42c | 1203 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1204 | |
bfd343aa | 1205 | if (unlikely(blk_mq_queue_enter(q, GFP_KERNEL))) { |
320ae51f | 1206 | bio_endio(bio, -EIO); |
07068d5b | 1207 | return NULL; |
320ae51f JA |
1208 | } |
1209 | ||
1210 | ctx = blk_mq_get_ctx(q); | |
1211 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1212 | ||
07068d5b | 1213 | if (rw_is_sync(bio->bi_rw)) |
27fbf4e8 | 1214 | rw |= REQ_SYNC; |
07068d5b | 1215 | |
320ae51f | 1216 | trace_block_getrq(q, bio, rw); |
cb96a42c ML |
1217 | blk_mq_set_alloc_data(&alloc_data, q, GFP_ATOMIC, false, ctx, |
1218 | hctx); | |
1219 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
5dee8577 | 1220 | if (unlikely(!rq)) { |
793597a6 | 1221 | __blk_mq_run_hw_queue(hctx); |
320ae51f JA |
1222 | blk_mq_put_ctx(ctx); |
1223 | trace_block_sleeprq(q, bio, rw); | |
793597a6 CH |
1224 | |
1225 | ctx = blk_mq_get_ctx(q); | |
320ae51f | 1226 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
cb96a42c ML |
1227 | blk_mq_set_alloc_data(&alloc_data, q, |
1228 | __GFP_WAIT|GFP_ATOMIC, false, ctx, hctx); | |
1229 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
1230 | ctx = alloc_data.ctx; | |
1231 | hctx = alloc_data.hctx; | |
320ae51f JA |
1232 | } |
1233 | ||
1234 | hctx->queued++; | |
07068d5b JA |
1235 | data->hctx = hctx; |
1236 | data->ctx = ctx; | |
1237 | return rq; | |
1238 | } | |
1239 | ||
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 | */ | |
1245 | static void blk_mq_make_request(struct request_queue *q, struct bio *bio) | |
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; | |
1251 | ||
1252 | blk_queue_bounce(q, &bio); | |
1253 | ||
1254 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1255 | bio_endio(bio, -EIO); | |
1256 | return; | |
1257 | } | |
1258 | ||
1259 | rq = blk_mq_map_request(q, bio, &data); | |
1260 | if (unlikely(!rq)) | |
1261 | return; | |
1262 | ||
1263 | if (unlikely(is_flush_fua)) { | |
1264 | blk_mq_bio_to_request(rq, bio); | |
1265 | blk_insert_flush(rq); | |
1266 | goto run_queue; | |
1267 | } | |
1268 | ||
e167dfb5 JA |
1269 | /* |
1270 | * If the driver supports defer issued based on 'last', then | |
1271 | * queue it up like normal since we can potentially save some | |
1272 | * CPU this way. | |
1273 | */ | |
1274 | if (is_sync && !(data.hctx->flags & BLK_MQ_F_DEFER_ISSUE)) { | |
74c45052 JA |
1275 | struct blk_mq_queue_data bd = { |
1276 | .rq = rq, | |
1277 | .list = NULL, | |
1278 | .last = 1 | |
1279 | }; | |
07068d5b JA |
1280 | int ret; |
1281 | ||
1282 | blk_mq_bio_to_request(rq, bio); | |
07068d5b JA |
1283 | |
1284 | /* | |
1285 | * For OK queue, we are done. For error, kill it. Any other | |
1286 | * error (busy), just add it to our list as we previously | |
1287 | * would have done | |
1288 | */ | |
74c45052 | 1289 | ret = q->mq_ops->queue_rq(data.hctx, &bd); |
07068d5b JA |
1290 | if (ret == BLK_MQ_RQ_QUEUE_OK) |
1291 | goto done; | |
1292 | else { | |
1293 | __blk_mq_requeue_request(rq); | |
1294 | ||
1295 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1296 | rq->errors = -EIO; | |
c8a446ad | 1297 | blk_mq_end_request(rq, rq->errors); |
07068d5b JA |
1298 | goto done; |
1299 | } | |
1300 | } | |
1301 | } | |
1302 | ||
1303 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { | |
1304 | /* | |
1305 | * For a SYNC request, send it to the hardware immediately. For | |
1306 | * an ASYNC request, just ensure that we run it later on. The | |
1307 | * latter allows for merging opportunities and more efficient | |
1308 | * dispatching. | |
1309 | */ | |
1310 | run_queue: | |
1311 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
1312 | } | |
1313 | done: | |
1314 | blk_mq_put_ctx(data.ctx); | |
1315 | } | |
1316 | ||
1317 | /* | |
1318 | * Single hardware queue variant. This will attempt to use any per-process | |
1319 | * plug for merging and IO deferral. | |
1320 | */ | |
1321 | static void blk_sq_make_request(struct request_queue *q, struct bio *bio) | |
1322 | { | |
1323 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1324 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1325 | unsigned int use_plug, request_count = 0; | |
1326 | struct blk_map_ctx data; | |
1327 | struct request *rq; | |
1328 | ||
1329 | /* | |
1330 | * If we have multiple hardware queues, just go directly to | |
1331 | * one of those for sync IO. | |
1332 | */ | |
1333 | use_plug = !is_flush_fua && !is_sync; | |
1334 | ||
1335 | blk_queue_bounce(q, &bio); | |
1336 | ||
1337 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1338 | bio_endio(bio, -EIO); | |
1339 | return; | |
1340 | } | |
1341 | ||
1342 | if (use_plug && !blk_queue_nomerges(q) && | |
1343 | blk_attempt_plug_merge(q, bio, &request_count)) | |
1344 | return; | |
1345 | ||
1346 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec JA |
1347 | if (unlikely(!rq)) |
1348 | return; | |
320ae51f JA |
1349 | |
1350 | if (unlikely(is_flush_fua)) { | |
1351 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1352 | blk_insert_flush(rq); |
1353 | goto run_queue; | |
1354 | } | |
1355 | ||
1356 | /* | |
1357 | * A task plug currently exists. Since this is completely lockless, | |
1358 | * utilize that to temporarily store requests until the task is | |
1359 | * either done or scheduled away. | |
1360 | */ | |
1361 | if (use_plug) { | |
1362 | struct blk_plug *plug = current->plug; | |
1363 | ||
1364 | if (plug) { | |
1365 | blk_mq_bio_to_request(rq, bio); | |
92f399c7 | 1366 | if (list_empty(&plug->mq_list)) |
320ae51f JA |
1367 | trace_block_plug(q); |
1368 | else if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
1369 | blk_flush_plug_list(plug, false); | |
1370 | trace_block_plug(q); | |
1371 | } | |
1372 | list_add_tail(&rq->queuelist, &plug->mq_list); | |
07068d5b | 1373 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1374 | return; |
1375 | } | |
1376 | } | |
1377 | ||
07068d5b JA |
1378 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1379 | /* | |
1380 | * For a SYNC request, send it to the hardware immediately. For | |
1381 | * an ASYNC request, just ensure that we run it later on. The | |
1382 | * latter allows for merging opportunities and more efficient | |
1383 | * dispatching. | |
1384 | */ | |
1385 | run_queue: | |
1386 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1387 | } |
1388 | ||
07068d5b | 1389 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1390 | } |
1391 | ||
1392 | /* | |
1393 | * Default mapping to a software queue, since we use one per CPU. | |
1394 | */ | |
1395 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1396 | { | |
1397 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1398 | } | |
1399 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1400 | ||
24d2f903 CH |
1401 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1402 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1403 | { |
e9b267d9 | 1404 | struct page *page; |
320ae51f | 1405 | |
24d2f903 | 1406 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1407 | int i; |
320ae51f | 1408 | |
24d2f903 CH |
1409 | for (i = 0; i < tags->nr_tags; i++) { |
1410 | if (!tags->rqs[i]) | |
e9b267d9 | 1411 | continue; |
24d2f903 CH |
1412 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1413 | hctx_idx, i); | |
a5164405 | 1414 | tags->rqs[i] = NULL; |
e9b267d9 | 1415 | } |
320ae51f | 1416 | } |
320ae51f | 1417 | |
24d2f903 CH |
1418 | while (!list_empty(&tags->page_list)) { |
1419 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1420 | list_del_init(&page->lru); |
320ae51f JA |
1421 | __free_pages(page, page->private); |
1422 | } | |
1423 | ||
24d2f903 | 1424 | kfree(tags->rqs); |
320ae51f | 1425 | |
24d2f903 | 1426 | blk_mq_free_tags(tags); |
320ae51f JA |
1427 | } |
1428 | ||
1429 | static size_t order_to_size(unsigned int order) | |
1430 | { | |
4ca08500 | 1431 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1432 | } |
1433 | ||
24d2f903 CH |
1434 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1435 | unsigned int hctx_idx) | |
320ae51f | 1436 | { |
24d2f903 | 1437 | struct blk_mq_tags *tags; |
320ae51f JA |
1438 | unsigned int i, j, entries_per_page, max_order = 4; |
1439 | size_t rq_size, left; | |
1440 | ||
24d2f903 | 1441 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
24391c0d SL |
1442 | set->numa_node, |
1443 | BLK_MQ_FLAG_TO_ALLOC_POLICY(set->flags)); | |
24d2f903 CH |
1444 | if (!tags) |
1445 | return NULL; | |
320ae51f | 1446 | |
24d2f903 CH |
1447 | INIT_LIST_HEAD(&tags->page_list); |
1448 | ||
a5164405 JA |
1449 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1450 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1451 | set->numa_node); | |
24d2f903 CH |
1452 | if (!tags->rqs) { |
1453 | blk_mq_free_tags(tags); | |
1454 | return NULL; | |
1455 | } | |
320ae51f JA |
1456 | |
1457 | /* | |
1458 | * rq_size is the size of the request plus driver payload, rounded | |
1459 | * to the cacheline size | |
1460 | */ | |
24d2f903 | 1461 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1462 | cache_line_size()); |
24d2f903 | 1463 | left = rq_size * set->queue_depth; |
320ae51f | 1464 | |
24d2f903 | 1465 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1466 | int this_order = max_order; |
1467 | struct page *page; | |
1468 | int to_do; | |
1469 | void *p; | |
1470 | ||
1471 | while (left < order_to_size(this_order - 1) && this_order) | |
1472 | this_order--; | |
1473 | ||
1474 | do { | |
a5164405 | 1475 | page = alloc_pages_node(set->numa_node, |
ac211175 | 1476 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO, |
a5164405 | 1477 | this_order); |
320ae51f JA |
1478 | if (page) |
1479 | break; | |
1480 | if (!this_order--) | |
1481 | break; | |
1482 | if (order_to_size(this_order) < rq_size) | |
1483 | break; | |
1484 | } while (1); | |
1485 | ||
1486 | if (!page) | |
24d2f903 | 1487 | goto fail; |
320ae51f JA |
1488 | |
1489 | page->private = this_order; | |
24d2f903 | 1490 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1491 | |
1492 | p = page_address(page); | |
1493 | entries_per_page = order_to_size(this_order) / rq_size; | |
24d2f903 | 1494 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1495 | left -= to_do * rq_size; |
1496 | for (j = 0; j < to_do; j++) { | |
24d2f903 CH |
1497 | tags->rqs[i] = p; |
1498 | if (set->ops->init_request) { | |
1499 | if (set->ops->init_request(set->driver_data, | |
1500 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1501 | set->numa_node)) { |
1502 | tags->rqs[i] = NULL; | |
24d2f903 | 1503 | goto fail; |
a5164405 | 1504 | } |
e9b267d9 CH |
1505 | } |
1506 | ||
320ae51f JA |
1507 | p += rq_size; |
1508 | i++; | |
1509 | } | |
1510 | } | |
1511 | ||
24d2f903 | 1512 | return tags; |
320ae51f | 1513 | |
24d2f903 | 1514 | fail: |
24d2f903 CH |
1515 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1516 | return NULL; | |
320ae51f JA |
1517 | } |
1518 | ||
1429d7c9 JA |
1519 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1520 | { | |
1521 | kfree(bitmap->map); | |
1522 | } | |
1523 | ||
1524 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1525 | { | |
1526 | unsigned int bpw = 8, total, num_maps, i; | |
1527 | ||
1528 | bitmap->bits_per_word = bpw; | |
1529 | ||
1530 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1531 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1532 | GFP_KERNEL, node); | |
1533 | if (!bitmap->map) | |
1534 | return -ENOMEM; | |
1535 | ||
1429d7c9 JA |
1536 | total = nr_cpu_ids; |
1537 | for (i = 0; i < num_maps; i++) { | |
1538 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1539 | total -= bitmap->map[i].depth; | |
1540 | } | |
1541 | ||
1542 | return 0; | |
1543 | } | |
1544 | ||
484b4061 JA |
1545 | static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) |
1546 | { | |
1547 | struct request_queue *q = hctx->queue; | |
1548 | struct blk_mq_ctx *ctx; | |
1549 | LIST_HEAD(tmp); | |
1550 | ||
1551 | /* | |
1552 | * Move ctx entries to new CPU, if this one is going away. | |
1553 | */ | |
1554 | ctx = __blk_mq_get_ctx(q, cpu); | |
1555 | ||
1556 | spin_lock(&ctx->lock); | |
1557 | if (!list_empty(&ctx->rq_list)) { | |
1558 | list_splice_init(&ctx->rq_list, &tmp); | |
1559 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1560 | } | |
1561 | spin_unlock(&ctx->lock); | |
1562 | ||
1563 | if (list_empty(&tmp)) | |
1564 | return NOTIFY_OK; | |
1565 | ||
1566 | ctx = blk_mq_get_ctx(q); | |
1567 | spin_lock(&ctx->lock); | |
1568 | ||
1569 | while (!list_empty(&tmp)) { | |
1570 | struct request *rq; | |
1571 | ||
1572 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1573 | rq->mq_ctx = ctx; | |
1574 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1575 | } | |
1576 | ||
1577 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1578 | blk_mq_hctx_mark_pending(hctx, ctx); | |
1579 | ||
1580 | spin_unlock(&ctx->lock); | |
1581 | ||
1582 | blk_mq_run_hw_queue(hctx, true); | |
1583 | blk_mq_put_ctx(ctx); | |
1584 | return NOTIFY_OK; | |
1585 | } | |
1586 | ||
484b4061 JA |
1587 | static int blk_mq_hctx_notify(void *data, unsigned long action, |
1588 | unsigned int cpu) | |
1589 | { | |
1590 | struct blk_mq_hw_ctx *hctx = data; | |
1591 | ||
1592 | if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) | |
1593 | return blk_mq_hctx_cpu_offline(hctx, cpu); | |
2a34c087 ML |
1594 | |
1595 | /* | |
1596 | * In case of CPU online, tags may be reallocated | |
1597 | * in blk_mq_map_swqueue() after mapping is updated. | |
1598 | */ | |
484b4061 JA |
1599 | |
1600 | return NOTIFY_OK; | |
1601 | } | |
1602 | ||
08e98fc6 ML |
1603 | static void blk_mq_exit_hctx(struct request_queue *q, |
1604 | struct blk_mq_tag_set *set, | |
1605 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
1606 | { | |
f70ced09 ML |
1607 | unsigned flush_start_tag = set->queue_depth; |
1608 | ||
08e98fc6 ML |
1609 | blk_mq_tag_idle(hctx); |
1610 | ||
f70ced09 ML |
1611 | if (set->ops->exit_request) |
1612 | set->ops->exit_request(set->driver_data, | |
1613 | hctx->fq->flush_rq, hctx_idx, | |
1614 | flush_start_tag + hctx_idx); | |
1615 | ||
08e98fc6 ML |
1616 | if (set->ops->exit_hctx) |
1617 | set->ops->exit_hctx(hctx, hctx_idx); | |
1618 | ||
1619 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
f70ced09 | 1620 | blk_free_flush_queue(hctx->fq); |
08e98fc6 ML |
1621 | kfree(hctx->ctxs); |
1622 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1623 | } | |
1624 | ||
624dbe47 ML |
1625 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1626 | struct blk_mq_tag_set *set, int nr_queue) | |
1627 | { | |
1628 | struct blk_mq_hw_ctx *hctx; | |
1629 | unsigned int i; | |
1630 | ||
1631 | queue_for_each_hw_ctx(q, hctx, i) { | |
1632 | if (i == nr_queue) | |
1633 | break; | |
08e98fc6 | 1634 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 1635 | } |
624dbe47 ML |
1636 | } |
1637 | ||
1638 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1639 | struct blk_mq_tag_set *set) | |
1640 | { | |
1641 | struct blk_mq_hw_ctx *hctx; | |
1642 | unsigned int i; | |
1643 | ||
e09aae7e | 1644 | queue_for_each_hw_ctx(q, hctx, i) |
624dbe47 | 1645 | free_cpumask_var(hctx->cpumask); |
624dbe47 ML |
1646 | } |
1647 | ||
08e98fc6 ML |
1648 | static int blk_mq_init_hctx(struct request_queue *q, |
1649 | struct blk_mq_tag_set *set, | |
1650 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 1651 | { |
08e98fc6 | 1652 | int node; |
f70ced09 | 1653 | unsigned flush_start_tag = set->queue_depth; |
08e98fc6 ML |
1654 | |
1655 | node = hctx->numa_node; | |
1656 | if (node == NUMA_NO_NODE) | |
1657 | node = hctx->numa_node = set->numa_node; | |
1658 | ||
1659 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); | |
1660 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
1661 | spin_lock_init(&hctx->lock); | |
1662 | INIT_LIST_HEAD(&hctx->dispatch); | |
1663 | hctx->queue = q; | |
1664 | hctx->queue_num = hctx_idx; | |
1665 | hctx->flags = set->flags; | |
08e98fc6 ML |
1666 | |
1667 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1668 | blk_mq_hctx_notify, hctx); | |
1669 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1670 | ||
1671 | hctx->tags = set->tags[hctx_idx]; | |
320ae51f JA |
1672 | |
1673 | /* | |
08e98fc6 ML |
1674 | * Allocate space for all possible cpus to avoid allocation at |
1675 | * runtime | |
320ae51f | 1676 | */ |
08e98fc6 ML |
1677 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), |
1678 | GFP_KERNEL, node); | |
1679 | if (!hctx->ctxs) | |
1680 | goto unregister_cpu_notifier; | |
320ae51f | 1681 | |
08e98fc6 ML |
1682 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
1683 | goto free_ctxs; | |
320ae51f | 1684 | |
08e98fc6 | 1685 | hctx->nr_ctx = 0; |
320ae51f | 1686 | |
08e98fc6 ML |
1687 | if (set->ops->init_hctx && |
1688 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
1689 | goto free_bitmap; | |
320ae51f | 1690 | |
f70ced09 ML |
1691 | hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); |
1692 | if (!hctx->fq) | |
1693 | goto exit_hctx; | |
320ae51f | 1694 | |
f70ced09 ML |
1695 | if (set->ops->init_request && |
1696 | set->ops->init_request(set->driver_data, | |
1697 | hctx->fq->flush_rq, hctx_idx, | |
1698 | flush_start_tag + hctx_idx, node)) | |
1699 | goto free_fq; | |
320ae51f | 1700 | |
08e98fc6 | 1701 | return 0; |
320ae51f | 1702 | |
f70ced09 ML |
1703 | free_fq: |
1704 | kfree(hctx->fq); | |
1705 | exit_hctx: | |
1706 | if (set->ops->exit_hctx) | |
1707 | set->ops->exit_hctx(hctx, hctx_idx); | |
08e98fc6 ML |
1708 | free_bitmap: |
1709 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1710 | free_ctxs: | |
1711 | kfree(hctx->ctxs); | |
1712 | unregister_cpu_notifier: | |
1713 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
320ae51f | 1714 | |
08e98fc6 ML |
1715 | return -1; |
1716 | } | |
320ae51f | 1717 | |
08e98fc6 ML |
1718 | static int blk_mq_init_hw_queues(struct request_queue *q, |
1719 | struct blk_mq_tag_set *set) | |
1720 | { | |
1721 | struct blk_mq_hw_ctx *hctx; | |
1722 | unsigned int i; | |
320ae51f | 1723 | |
08e98fc6 ML |
1724 | /* |
1725 | * Initialize hardware queues | |
1726 | */ | |
1727 | queue_for_each_hw_ctx(q, hctx, i) { | |
1728 | if (blk_mq_init_hctx(q, set, hctx, i)) | |
320ae51f JA |
1729 | break; |
1730 | } | |
1731 | ||
1732 | if (i == q->nr_hw_queues) | |
1733 | return 0; | |
1734 | ||
1735 | /* | |
1736 | * Init failed | |
1737 | */ | |
624dbe47 | 1738 | blk_mq_exit_hw_queues(q, set, i); |
320ae51f JA |
1739 | |
1740 | return 1; | |
1741 | } | |
1742 | ||
1743 | static void blk_mq_init_cpu_queues(struct request_queue *q, | |
1744 | unsigned int nr_hw_queues) | |
1745 | { | |
1746 | unsigned int i; | |
1747 | ||
1748 | for_each_possible_cpu(i) { | |
1749 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1750 | struct blk_mq_hw_ctx *hctx; | |
1751 | ||
1752 | memset(__ctx, 0, sizeof(*__ctx)); | |
1753 | __ctx->cpu = i; | |
1754 | spin_lock_init(&__ctx->lock); | |
1755 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1756 | __ctx->queue = q; | |
1757 | ||
1758 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1759 | if (!cpu_online(i)) |
1760 | continue; | |
1761 | ||
e4043dcf | 1762 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1763 | |
320ae51f JA |
1764 | /* |
1765 | * Set local node, IFF we have more than one hw queue. If | |
1766 | * not, we remain on the home node of the device | |
1767 | */ | |
1768 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
1769 | hctx->numa_node = cpu_to_node(i); | |
1770 | } | |
1771 | } | |
1772 | ||
1773 | static void blk_mq_map_swqueue(struct request_queue *q) | |
1774 | { | |
1775 | unsigned int i; | |
1776 | struct blk_mq_hw_ctx *hctx; | |
1777 | struct blk_mq_ctx *ctx; | |
2a34c087 | 1778 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f JA |
1779 | |
1780 | queue_for_each_hw_ctx(q, hctx, i) { | |
e4043dcf | 1781 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1782 | hctx->nr_ctx = 0; |
1783 | } | |
1784 | ||
1785 | /* | |
1786 | * Map software to hardware queues | |
1787 | */ | |
1788 | queue_for_each_ctx(q, ctx, i) { | |
1789 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
e4043dcf JA |
1790 | if (!cpu_online(i)) |
1791 | continue; | |
1792 | ||
320ae51f | 1793 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1794 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1795 | ctx->index_hw = hctx->nr_ctx; |
1796 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1797 | } | |
506e931f JA |
1798 | |
1799 | queue_for_each_hw_ctx(q, hctx, i) { | |
889fa31f CY |
1800 | struct blk_mq_ctxmap *map = &hctx->ctx_map; |
1801 | ||
484b4061 | 1802 | /* |
a68aafa5 JA |
1803 | * If no software queues are mapped to this hardware queue, |
1804 | * disable it and free the request entries. | |
484b4061 JA |
1805 | */ |
1806 | if (!hctx->nr_ctx) { | |
484b4061 JA |
1807 | if (set->tags[i]) { |
1808 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1809 | set->tags[i] = NULL; | |
484b4061 | 1810 | } |
2a34c087 | 1811 | hctx->tags = NULL; |
484b4061 JA |
1812 | continue; |
1813 | } | |
1814 | ||
2a34c087 ML |
1815 | /* unmapped hw queue can be remapped after CPU topo changed */ |
1816 | if (!set->tags[i]) | |
1817 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1818 | hctx->tags = set->tags[i]; | |
1819 | WARN_ON(!hctx->tags); | |
1820 | ||
889fa31f CY |
1821 | /* |
1822 | * Set the map size to the number of mapped software queues. | |
1823 | * This is more accurate and more efficient than looping | |
1824 | * over all possibly mapped software queues. | |
1825 | */ | |
569fd0ce | 1826 | map->size = DIV_ROUND_UP(hctx->nr_ctx, map->bits_per_word); |
889fa31f | 1827 | |
484b4061 JA |
1828 | /* |
1829 | * Initialize batch roundrobin counts | |
1830 | */ | |
506e931f JA |
1831 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1832 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1833 | } | |
320ae51f JA |
1834 | } |
1835 | ||
0d2602ca JA |
1836 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |
1837 | { | |
1838 | struct blk_mq_hw_ctx *hctx; | |
1839 | struct request_queue *q; | |
1840 | bool shared; | |
1841 | int i; | |
1842 | ||
1843 | if (set->tag_list.next == set->tag_list.prev) | |
1844 | shared = false; | |
1845 | else | |
1846 | shared = true; | |
1847 | ||
1848 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1849 | blk_mq_freeze_queue(q); | |
1850 | ||
1851 | queue_for_each_hw_ctx(q, hctx, i) { | |
1852 | if (shared) | |
1853 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1854 | else | |
1855 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1856 | } | |
1857 | blk_mq_unfreeze_queue(q); | |
1858 | } | |
1859 | } | |
1860 | ||
1861 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1862 | { | |
1863 | struct blk_mq_tag_set *set = q->tag_set; | |
1864 | ||
0d2602ca JA |
1865 | mutex_lock(&set->tag_list_lock); |
1866 | list_del_init(&q->tag_set_list); | |
1867 | blk_mq_update_tag_set_depth(set); | |
1868 | mutex_unlock(&set->tag_list_lock); | |
0d2602ca JA |
1869 | } |
1870 | ||
1871 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1872 | struct request_queue *q) | |
1873 | { | |
1874 | q->tag_set = set; | |
1875 | ||
1876 | mutex_lock(&set->tag_list_lock); | |
1877 | list_add_tail(&q->tag_set_list, &set->tag_list); | |
1878 | blk_mq_update_tag_set_depth(set); | |
1879 | mutex_unlock(&set->tag_list_lock); | |
1880 | } | |
1881 | ||
e09aae7e ML |
1882 | /* |
1883 | * It is the actual release handler for mq, but we do it from | |
1884 | * request queue's release handler for avoiding use-after-free | |
1885 | * and headache because q->mq_kobj shouldn't have been introduced, | |
1886 | * but we can't group ctx/kctx kobj without it. | |
1887 | */ | |
1888 | void blk_mq_release(struct request_queue *q) | |
1889 | { | |
1890 | struct blk_mq_hw_ctx *hctx; | |
1891 | unsigned int i; | |
1892 | ||
1893 | /* hctx kobj stays in hctx */ | |
1894 | queue_for_each_hw_ctx(q, hctx, i) | |
1895 | kfree(hctx); | |
1896 | ||
1897 | kfree(q->queue_hw_ctx); | |
1898 | ||
1899 | /* ctx kobj stays in queue_ctx */ | |
1900 | free_percpu(q->queue_ctx); | |
1901 | } | |
1902 | ||
24d2f903 | 1903 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
b62c21b7 MS |
1904 | { |
1905 | struct request_queue *uninit_q, *q; | |
1906 | ||
1907 | uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); | |
1908 | if (!uninit_q) | |
1909 | return ERR_PTR(-ENOMEM); | |
1910 | ||
1911 | q = blk_mq_init_allocated_queue(set, uninit_q); | |
1912 | if (IS_ERR(q)) | |
1913 | blk_cleanup_queue(uninit_q); | |
1914 | ||
1915 | return q; | |
1916 | } | |
1917 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1918 | ||
1919 | struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, | |
1920 | struct request_queue *q) | |
320ae51f JA |
1921 | { |
1922 | struct blk_mq_hw_ctx **hctxs; | |
e6cdb092 | 1923 | struct blk_mq_ctx __percpu *ctx; |
f14bbe77 | 1924 | unsigned int *map; |
320ae51f JA |
1925 | int i; |
1926 | ||
320ae51f JA |
1927 | ctx = alloc_percpu(struct blk_mq_ctx); |
1928 | if (!ctx) | |
1929 | return ERR_PTR(-ENOMEM); | |
1930 | ||
24d2f903 CH |
1931 | hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, |
1932 | set->numa_node); | |
320ae51f JA |
1933 | |
1934 | if (!hctxs) | |
1935 | goto err_percpu; | |
1936 | ||
f14bbe77 JA |
1937 | map = blk_mq_make_queue_map(set); |
1938 | if (!map) | |
1939 | goto err_map; | |
1940 | ||
24d2f903 | 1941 | for (i = 0; i < set->nr_hw_queues; i++) { |
f14bbe77 JA |
1942 | int node = blk_mq_hw_queue_to_node(map, i); |
1943 | ||
cdef54dd CH |
1944 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1945 | GFP_KERNEL, node); | |
320ae51f JA |
1946 | if (!hctxs[i]) |
1947 | goto err_hctxs; | |
1948 | ||
a86073e4 JA |
1949 | if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, |
1950 | node)) | |
e4043dcf JA |
1951 | goto err_hctxs; |
1952 | ||
0d2602ca | 1953 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1954 | hctxs[i]->numa_node = node; |
320ae51f JA |
1955 | hctxs[i]->queue_num = i; |
1956 | } | |
1957 | ||
17497acb TH |
1958 | /* |
1959 | * Init percpu_ref in atomic mode so that it's faster to shutdown. | |
1960 | * See blk_register_queue() for details. | |
1961 | */ | |
a34375ef | 1962 | if (percpu_ref_init(&q->mq_usage_counter, blk_mq_usage_counter_release, |
17497acb | 1963 | PERCPU_REF_INIT_ATOMIC, GFP_KERNEL)) |
b62c21b7 | 1964 | goto err_hctxs; |
3d2936f4 | 1965 | |
320ae51f | 1966 | setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); |
c76cbbcf | 1967 | blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30000); |
320ae51f JA |
1968 | |
1969 | q->nr_queues = nr_cpu_ids; | |
24d2f903 | 1970 | q->nr_hw_queues = set->nr_hw_queues; |
f14bbe77 | 1971 | q->mq_map = map; |
320ae51f JA |
1972 | |
1973 | q->queue_ctx = ctx; | |
1974 | q->queue_hw_ctx = hctxs; | |
1975 | ||
24d2f903 | 1976 | q->mq_ops = set->ops; |
94eddfbe | 1977 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 1978 | |
05f1dd53 JA |
1979 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
1980 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
1981 | ||
1be036e9 CH |
1982 | q->sg_reserved_size = INT_MAX; |
1983 | ||
6fca6a61 CH |
1984 | INIT_WORK(&q->requeue_work, blk_mq_requeue_work); |
1985 | INIT_LIST_HEAD(&q->requeue_list); | |
1986 | spin_lock_init(&q->requeue_lock); | |
1987 | ||
07068d5b JA |
1988 | if (q->nr_hw_queues > 1) |
1989 | blk_queue_make_request(q, blk_mq_make_request); | |
1990 | else | |
1991 | blk_queue_make_request(q, blk_sq_make_request); | |
1992 | ||
eba71768 JA |
1993 | /* |
1994 | * Do this after blk_queue_make_request() overrides it... | |
1995 | */ | |
1996 | q->nr_requests = set->queue_depth; | |
1997 | ||
24d2f903 CH |
1998 | if (set->ops->complete) |
1999 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 2000 | |
24d2f903 | 2001 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 2002 | |
24d2f903 | 2003 | if (blk_mq_init_hw_queues(q, set)) |
b62c21b7 | 2004 | goto err_hctxs; |
18741986 | 2005 | |
320ae51f JA |
2006 | mutex_lock(&all_q_mutex); |
2007 | list_add_tail(&q->all_q_node, &all_q_list); | |
2008 | mutex_unlock(&all_q_mutex); | |
2009 | ||
0d2602ca JA |
2010 | blk_mq_add_queue_tag_set(set, q); |
2011 | ||
484b4061 JA |
2012 | blk_mq_map_swqueue(q); |
2013 | ||
320ae51f | 2014 | return q; |
18741986 | 2015 | |
320ae51f | 2016 | err_hctxs: |
f14bbe77 | 2017 | kfree(map); |
24d2f903 | 2018 | for (i = 0; i < set->nr_hw_queues; i++) { |
320ae51f JA |
2019 | if (!hctxs[i]) |
2020 | break; | |
e4043dcf | 2021 | free_cpumask_var(hctxs[i]->cpumask); |
cdef54dd | 2022 | kfree(hctxs[i]); |
320ae51f | 2023 | } |
f14bbe77 | 2024 | err_map: |
320ae51f JA |
2025 | kfree(hctxs); |
2026 | err_percpu: | |
2027 | free_percpu(ctx); | |
2028 | return ERR_PTR(-ENOMEM); | |
2029 | } | |
b62c21b7 | 2030 | EXPORT_SYMBOL(blk_mq_init_allocated_queue); |
320ae51f JA |
2031 | |
2032 | void blk_mq_free_queue(struct request_queue *q) | |
2033 | { | |
624dbe47 | 2034 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 2035 | |
0d2602ca JA |
2036 | blk_mq_del_queue_tag_set(q); |
2037 | ||
624dbe47 ML |
2038 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
2039 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 2040 | |
add703fd | 2041 | percpu_ref_exit(&q->mq_usage_counter); |
3d2936f4 | 2042 | |
320ae51f JA |
2043 | kfree(q->mq_map); |
2044 | ||
320ae51f JA |
2045 | q->mq_map = NULL; |
2046 | ||
2047 | mutex_lock(&all_q_mutex); | |
2048 | list_del_init(&q->all_q_node); | |
2049 | mutex_unlock(&all_q_mutex); | |
2050 | } | |
320ae51f JA |
2051 | |
2052 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
f618ef7c | 2053 | static void blk_mq_queue_reinit(struct request_queue *q) |
320ae51f | 2054 | { |
f3af020b | 2055 | WARN_ON_ONCE(!q->mq_freeze_depth); |
320ae51f | 2056 | |
67aec14c JA |
2057 | blk_mq_sysfs_unregister(q); |
2058 | ||
320ae51f JA |
2059 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues); |
2060 | ||
2061 | /* | |
2062 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
2063 | * we should change hctx numa_node according to new topology (this | |
2064 | * involves free and re-allocate memory, worthy doing?) | |
2065 | */ | |
2066 | ||
2067 | blk_mq_map_swqueue(q); | |
2068 | ||
67aec14c | 2069 | blk_mq_sysfs_register(q); |
320ae51f JA |
2070 | } |
2071 | ||
f618ef7c PG |
2072 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
2073 | unsigned long action, void *hcpu) | |
320ae51f JA |
2074 | { |
2075 | struct request_queue *q; | |
2076 | ||
2077 | /* | |
9fccfed8 JA |
2078 | * Before new mappings are established, hotadded cpu might already |
2079 | * start handling requests. This doesn't break anything as we map | |
2080 | * offline CPUs to first hardware queue. We will re-init the queue | |
2081 | * below to get optimal settings. | |
320ae51f JA |
2082 | */ |
2083 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN && | |
2084 | action != CPU_ONLINE && action != CPU_ONLINE_FROZEN) | |
2085 | return NOTIFY_OK; | |
2086 | ||
2087 | mutex_lock(&all_q_mutex); | |
f3af020b TH |
2088 | |
2089 | /* | |
2090 | * We need to freeze and reinit all existing queues. Freezing | |
2091 | * involves synchronous wait for an RCU grace period and doing it | |
2092 | * one by one may take a long time. Start freezing all queues in | |
2093 | * one swoop and then wait for the completions so that freezing can | |
2094 | * take place in parallel. | |
2095 | */ | |
2096 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2097 | blk_mq_freeze_queue_start(q); | |
f054b56c | 2098 | list_for_each_entry(q, &all_q_list, all_q_node) { |
f3af020b TH |
2099 | blk_mq_freeze_queue_wait(q); |
2100 | ||
f054b56c ML |
2101 | /* |
2102 | * timeout handler can't touch hw queue during the | |
2103 | * reinitialization | |
2104 | */ | |
2105 | del_timer_sync(&q->timeout); | |
2106 | } | |
2107 | ||
320ae51f JA |
2108 | list_for_each_entry(q, &all_q_list, all_q_node) |
2109 | blk_mq_queue_reinit(q); | |
f3af020b TH |
2110 | |
2111 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2112 | blk_mq_unfreeze_queue(q); | |
2113 | ||
320ae51f JA |
2114 | mutex_unlock(&all_q_mutex); |
2115 | return NOTIFY_OK; | |
2116 | } | |
2117 | ||
a5164405 JA |
2118 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
2119 | { | |
2120 | int i; | |
2121 | ||
2122 | for (i = 0; i < set->nr_hw_queues; i++) { | |
2123 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
2124 | if (!set->tags[i]) | |
2125 | goto out_unwind; | |
2126 | } | |
2127 | ||
2128 | return 0; | |
2129 | ||
2130 | out_unwind: | |
2131 | while (--i >= 0) | |
2132 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2133 | ||
a5164405 JA |
2134 | return -ENOMEM; |
2135 | } | |
2136 | ||
2137 | /* | |
2138 | * Allocate the request maps associated with this tag_set. Note that this | |
2139 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
2140 | * will be updated to reflect the allocated depth. | |
2141 | */ | |
2142 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
2143 | { | |
2144 | unsigned int depth; | |
2145 | int err; | |
2146 | ||
2147 | depth = set->queue_depth; | |
2148 | do { | |
2149 | err = __blk_mq_alloc_rq_maps(set); | |
2150 | if (!err) | |
2151 | break; | |
2152 | ||
2153 | set->queue_depth >>= 1; | |
2154 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
2155 | err = -ENOMEM; | |
2156 | break; | |
2157 | } | |
2158 | } while (set->queue_depth); | |
2159 | ||
2160 | if (!set->queue_depth || err) { | |
2161 | pr_err("blk-mq: failed to allocate request map\n"); | |
2162 | return -ENOMEM; | |
2163 | } | |
2164 | ||
2165 | if (depth != set->queue_depth) | |
2166 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2167 | depth, set->queue_depth); | |
2168 | ||
2169 | return 0; | |
2170 | } | |
2171 | ||
a4391c64 JA |
2172 | /* |
2173 | * Alloc a tag set to be associated with one or more request queues. | |
2174 | * May fail with EINVAL for various error conditions. May adjust the | |
2175 | * requested depth down, if if it too large. In that case, the set | |
2176 | * value will be stored in set->queue_depth. | |
2177 | */ | |
24d2f903 CH |
2178 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2179 | { | |
205fb5f5 BVA |
2180 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
2181 | ||
24d2f903 CH |
2182 | if (!set->nr_hw_queues) |
2183 | return -EINVAL; | |
a4391c64 | 2184 | if (!set->queue_depth) |
24d2f903 CH |
2185 | return -EINVAL; |
2186 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2187 | return -EINVAL; | |
2188 | ||
f9018ac9 | 2189 | if (!set->ops->queue_rq || !set->ops->map_queue) |
24d2f903 CH |
2190 | return -EINVAL; |
2191 | ||
a4391c64 JA |
2192 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2193 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2194 | BLK_MQ_MAX_DEPTH); | |
2195 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2196 | } | |
24d2f903 | 2197 | |
6637fadf SL |
2198 | /* |
2199 | * If a crashdump is active, then we are potentially in a very | |
2200 | * memory constrained environment. Limit us to 1 queue and | |
2201 | * 64 tags to prevent using too much memory. | |
2202 | */ | |
2203 | if (is_kdump_kernel()) { | |
2204 | set->nr_hw_queues = 1; | |
2205 | set->queue_depth = min(64U, set->queue_depth); | |
2206 | } | |
2207 | ||
48479005 ML |
2208 | set->tags = kmalloc_node(set->nr_hw_queues * |
2209 | sizeof(struct blk_mq_tags *), | |
24d2f903 CH |
2210 | GFP_KERNEL, set->numa_node); |
2211 | if (!set->tags) | |
a5164405 | 2212 | return -ENOMEM; |
24d2f903 | 2213 | |
a5164405 JA |
2214 | if (blk_mq_alloc_rq_maps(set)) |
2215 | goto enomem; | |
24d2f903 | 2216 | |
0d2602ca JA |
2217 | mutex_init(&set->tag_list_lock); |
2218 | INIT_LIST_HEAD(&set->tag_list); | |
2219 | ||
24d2f903 | 2220 | return 0; |
a5164405 | 2221 | enomem: |
5676e7b6 RE |
2222 | kfree(set->tags); |
2223 | set->tags = NULL; | |
24d2f903 CH |
2224 | return -ENOMEM; |
2225 | } | |
2226 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2227 | ||
2228 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2229 | { | |
2230 | int i; | |
2231 | ||
484b4061 JA |
2232 | for (i = 0; i < set->nr_hw_queues; i++) { |
2233 | if (set->tags[i]) | |
2234 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2235 | } | |
2236 | ||
981bd189 | 2237 | kfree(set->tags); |
5676e7b6 | 2238 | set->tags = NULL; |
24d2f903 CH |
2239 | } |
2240 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2241 | ||
e3a2b3f9 JA |
2242 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2243 | { | |
2244 | struct blk_mq_tag_set *set = q->tag_set; | |
2245 | struct blk_mq_hw_ctx *hctx; | |
2246 | int i, ret; | |
2247 | ||
2248 | if (!set || nr > set->queue_depth) | |
2249 | return -EINVAL; | |
2250 | ||
2251 | ret = 0; | |
2252 | queue_for_each_hw_ctx(q, hctx, i) { | |
2253 | ret = blk_mq_tag_update_depth(hctx->tags, nr); | |
2254 | if (ret) | |
2255 | break; | |
2256 | } | |
2257 | ||
2258 | if (!ret) | |
2259 | q->nr_requests = nr; | |
2260 | ||
2261 | return ret; | |
2262 | } | |
2263 | ||
676141e4 JA |
2264 | void blk_mq_disable_hotplug(void) |
2265 | { | |
2266 | mutex_lock(&all_q_mutex); | |
2267 | } | |
2268 | ||
2269 | void blk_mq_enable_hotplug(void) | |
2270 | { | |
2271 | mutex_unlock(&all_q_mutex); | |
2272 | } | |
2273 | ||
320ae51f JA |
2274 | static int __init blk_mq_init(void) |
2275 | { | |
320ae51f JA |
2276 | blk_mq_cpu_init(); |
2277 | ||
add703fd | 2278 | hotcpu_notifier(blk_mq_queue_reinit_notify, 0); |
320ae51f JA |
2279 | |
2280 | return 0; | |
2281 | } | |
2282 | subsys_initcall(blk_mq_init); |