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Commit | Line | Data |
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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 | ||
bfd343aa | 81 | static int blk_mq_queue_enter(struct request_queue *q, gfp_t gfp) |
320ae51f | 82 | { |
add703fd TH |
83 | while (true) { |
84 | int ret; | |
320ae51f | 85 | |
add703fd TH |
86 | if (percpu_ref_tryget_live(&q->mq_usage_counter)) |
87 | return 0; | |
320ae51f | 88 | |
bfd343aa KB |
89 | if (!(gfp & __GFP_WAIT)) |
90 | return -EBUSY; | |
91 | ||
add703fd | 92 | ret = wait_event_interruptible(q->mq_freeze_wq, |
4ecd4fef CH |
93 | !atomic_read(&q->mq_freeze_depth) || |
94 | blk_queue_dying(q)); | |
add703fd TH |
95 | if (blk_queue_dying(q)) |
96 | return -ENODEV; | |
97 | if (ret) | |
98 | return ret; | |
99 | } | |
320ae51f JA |
100 | } |
101 | ||
102 | static void blk_mq_queue_exit(struct request_queue *q) | |
103 | { | |
add703fd TH |
104 | percpu_ref_put(&q->mq_usage_counter); |
105 | } | |
106 | ||
107 | static void blk_mq_usage_counter_release(struct percpu_ref *ref) | |
108 | { | |
109 | struct request_queue *q = | |
110 | container_of(ref, struct request_queue, mq_usage_counter); | |
111 | ||
112 | wake_up_all(&q->mq_freeze_wq); | |
320ae51f JA |
113 | } |
114 | ||
b4c6a028 | 115 | void blk_mq_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 116 | { |
4ecd4fef | 117 | int freeze_depth; |
cddd5d17 | 118 | |
4ecd4fef CH |
119 | freeze_depth = atomic_inc_return(&q->mq_freeze_depth); |
120 | if (freeze_depth == 1) { | |
9eca8046 | 121 | percpu_ref_kill(&q->mq_usage_counter); |
b94ec296 | 122 | blk_mq_run_hw_queues(q, false); |
cddd5d17 | 123 | } |
f3af020b | 124 | } |
b4c6a028 | 125 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start); |
f3af020b TH |
126 | |
127 | static void blk_mq_freeze_queue_wait(struct request_queue *q) | |
128 | { | |
add703fd | 129 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); |
43a5e4e2 ML |
130 | } |
131 | ||
f3af020b TH |
132 | /* |
133 | * Guarantee no request is in use, so we can change any data structure of | |
134 | * the queue afterward. | |
135 | */ | |
136 | void blk_mq_freeze_queue(struct request_queue *q) | |
137 | { | |
138 | blk_mq_freeze_queue_start(q); | |
139 | blk_mq_freeze_queue_wait(q); | |
140 | } | |
c761d96b | 141 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue); |
f3af020b | 142 | |
b4c6a028 | 143 | void blk_mq_unfreeze_queue(struct request_queue *q) |
320ae51f | 144 | { |
4ecd4fef | 145 | int freeze_depth; |
320ae51f | 146 | |
4ecd4fef CH |
147 | freeze_depth = atomic_dec_return(&q->mq_freeze_depth); |
148 | WARN_ON_ONCE(freeze_depth < 0); | |
149 | if (!freeze_depth) { | |
add703fd | 150 | percpu_ref_reinit(&q->mq_usage_counter); |
320ae51f | 151 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 152 | } |
320ae51f | 153 | } |
b4c6a028 | 154 | EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
320ae51f | 155 | |
aed3ea94 JA |
156 | void blk_mq_wake_waiters(struct request_queue *q) |
157 | { | |
158 | struct blk_mq_hw_ctx *hctx; | |
159 | unsigned int i; | |
160 | ||
161 | queue_for_each_hw_ctx(q, hctx, i) | |
162 | if (blk_mq_hw_queue_mapped(hctx)) | |
163 | blk_mq_tag_wakeup_all(hctx->tags, true); | |
3fd5940c KB |
164 | |
165 | /* | |
166 | * If we are called because the queue has now been marked as | |
167 | * dying, we need to ensure that processes currently waiting on | |
168 | * the queue are notified as well. | |
169 | */ | |
170 | wake_up_all(&q->mq_freeze_wq); | |
aed3ea94 JA |
171 | } |
172 | ||
320ae51f JA |
173 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) |
174 | { | |
175 | return blk_mq_has_free_tags(hctx->tags); | |
176 | } | |
177 | EXPORT_SYMBOL(blk_mq_can_queue); | |
178 | ||
94eddfbe JA |
179 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
180 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 181 | { |
94eddfbe JA |
182 | if (blk_queue_io_stat(q)) |
183 | rw_flags |= REQ_IO_STAT; | |
184 | ||
af76e555 CH |
185 | INIT_LIST_HEAD(&rq->queuelist); |
186 | /* csd/requeue_work/fifo_time is initialized before use */ | |
187 | rq->q = q; | |
320ae51f | 188 | rq->mq_ctx = ctx; |
0d2602ca | 189 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
190 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
191 | rq->cpu = -1; | |
af76e555 CH |
192 | INIT_HLIST_NODE(&rq->hash); |
193 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
194 | rq->rq_disk = NULL; |
195 | rq->part = NULL; | |
3ee32372 | 196 | rq->start_time = jiffies; |
af76e555 CH |
197 | #ifdef CONFIG_BLK_CGROUP |
198 | rq->rl = NULL; | |
0fec08b4 | 199 | set_start_time_ns(rq); |
af76e555 CH |
200 | rq->io_start_time_ns = 0; |
201 | #endif | |
202 | rq->nr_phys_segments = 0; | |
203 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
204 | rq->nr_integrity_segments = 0; | |
205 | #endif | |
af76e555 CH |
206 | rq->special = NULL; |
207 | /* tag was already set */ | |
208 | rq->errors = 0; | |
af76e555 | 209 | |
6f4a1626 TB |
210 | rq->cmd = rq->__cmd; |
211 | ||
af76e555 CH |
212 | rq->extra_len = 0; |
213 | rq->sense_len = 0; | |
214 | rq->resid_len = 0; | |
215 | rq->sense = NULL; | |
216 | ||
af76e555 | 217 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
218 | rq->timeout = 0; |
219 | ||
af76e555 CH |
220 | rq->end_io = NULL; |
221 | rq->end_io_data = NULL; | |
222 | rq->next_rq = NULL; | |
223 | ||
320ae51f JA |
224 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
225 | } | |
226 | ||
5dee8577 | 227 | static struct request * |
cb96a42c | 228 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) |
5dee8577 CH |
229 | { |
230 | struct request *rq; | |
231 | unsigned int tag; | |
232 | ||
cb96a42c | 233 | tag = blk_mq_get_tag(data); |
5dee8577 | 234 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 235 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 236 | |
cb96a42c | 237 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 238 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 239 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
240 | } |
241 | ||
242 | rq->tag = tag; | |
cb96a42c | 243 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); |
5dee8577 CH |
244 | return rq; |
245 | } | |
246 | ||
247 | return NULL; | |
248 | } | |
249 | ||
4ce01dd1 CH |
250 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp, |
251 | bool reserved) | |
320ae51f | 252 | { |
d852564f CH |
253 | struct blk_mq_ctx *ctx; |
254 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 255 | struct request *rq; |
cb96a42c | 256 | struct blk_mq_alloc_data alloc_data; |
a492f075 | 257 | int ret; |
320ae51f | 258 | |
bfd343aa | 259 | ret = blk_mq_queue_enter(q, gfp); |
a492f075 JL |
260 | if (ret) |
261 | return ERR_PTR(ret); | |
320ae51f | 262 | |
d852564f CH |
263 | ctx = blk_mq_get_ctx(q); |
264 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
265 | blk_mq_set_alloc_data(&alloc_data, q, gfp & ~__GFP_WAIT, |
266 | reserved, ctx, hctx); | |
d852564f | 267 | |
cb96a42c | 268 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
d852564f CH |
269 | if (!rq && (gfp & __GFP_WAIT)) { |
270 | __blk_mq_run_hw_queue(hctx); | |
271 | blk_mq_put_ctx(ctx); | |
272 | ||
273 | ctx = blk_mq_get_ctx(q); | |
274 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
275 | blk_mq_set_alloc_data(&alloc_data, q, gfp, reserved, ctx, |
276 | hctx); | |
277 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
278 | ctx = alloc_data.ctx; | |
d852564f CH |
279 | } |
280 | blk_mq_put_ctx(ctx); | |
c76541a9 KB |
281 | if (!rq) { |
282 | blk_mq_queue_exit(q); | |
a492f075 | 283 | return ERR_PTR(-EWOULDBLOCK); |
c76541a9 | 284 | } |
320ae51f JA |
285 | return rq; |
286 | } | |
4bb659b1 | 287 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 288 | |
320ae51f JA |
289 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
290 | struct blk_mq_ctx *ctx, struct request *rq) | |
291 | { | |
292 | const int tag = rq->tag; | |
293 | struct request_queue *q = rq->q; | |
294 | ||
0d2602ca JA |
295 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
296 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 297 | rq->cmd_flags = 0; |
0d2602ca | 298 | |
af76e555 | 299 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 300 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
320ae51f JA |
301 | blk_mq_queue_exit(q); |
302 | } | |
303 | ||
7c7f2f2b | 304 | void blk_mq_free_hctx_request(struct blk_mq_hw_ctx *hctx, struct request *rq) |
320ae51f JA |
305 | { |
306 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
320ae51f JA |
307 | |
308 | ctx->rq_completed[rq_is_sync(rq)]++; | |
320ae51f | 309 | __blk_mq_free_request(hctx, ctx, rq); |
7c7f2f2b JA |
310 | |
311 | } | |
312 | EXPORT_SYMBOL_GPL(blk_mq_free_hctx_request); | |
313 | ||
314 | void blk_mq_free_request(struct request *rq) | |
315 | { | |
316 | struct blk_mq_hw_ctx *hctx; | |
317 | struct request_queue *q = rq->q; | |
318 | ||
319 | hctx = q->mq_ops->map_queue(q, rq->mq_ctx->cpu); | |
320 | blk_mq_free_hctx_request(hctx, rq); | |
320ae51f | 321 | } |
1a3b595a | 322 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 323 | |
c8a446ad | 324 | inline void __blk_mq_end_request(struct request *rq, int error) |
320ae51f | 325 | { |
0d11e6ac ML |
326 | blk_account_io_done(rq); |
327 | ||
91b63639 | 328 | if (rq->end_io) { |
320ae51f | 329 | rq->end_io(rq, error); |
91b63639 CH |
330 | } else { |
331 | if (unlikely(blk_bidi_rq(rq))) | |
332 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 333 | blk_mq_free_request(rq); |
91b63639 | 334 | } |
320ae51f | 335 | } |
c8a446ad | 336 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 337 | |
c8a446ad | 338 | void blk_mq_end_request(struct request *rq, int error) |
63151a44 CH |
339 | { |
340 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
341 | BUG(); | |
c8a446ad | 342 | __blk_mq_end_request(rq, error); |
63151a44 | 343 | } |
c8a446ad | 344 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 345 | |
30a91cb4 | 346 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 347 | { |
3d6efbf6 | 348 | struct request *rq = data; |
320ae51f | 349 | |
30a91cb4 | 350 | rq->q->softirq_done_fn(rq); |
320ae51f | 351 | } |
320ae51f | 352 | |
ed851860 | 353 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
354 | { |
355 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 356 | bool shared = false; |
320ae51f JA |
357 | int cpu; |
358 | ||
38535201 | 359 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
360 | rq->q->softirq_done_fn(rq); |
361 | return; | |
362 | } | |
320ae51f JA |
363 | |
364 | cpu = get_cpu(); | |
38535201 CH |
365 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
366 | shared = cpus_share_cache(cpu, ctx->cpu); | |
367 | ||
368 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 369 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
370 | rq->csd.info = rq; |
371 | rq->csd.flags = 0; | |
c46fff2a | 372 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 373 | } else { |
30a91cb4 | 374 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 375 | } |
320ae51f JA |
376 | put_cpu(); |
377 | } | |
30a91cb4 | 378 | |
ed851860 JA |
379 | void __blk_mq_complete_request(struct request *rq) |
380 | { | |
381 | struct request_queue *q = rq->q; | |
382 | ||
383 | if (!q->softirq_done_fn) | |
c8a446ad | 384 | blk_mq_end_request(rq, rq->errors); |
ed851860 JA |
385 | else |
386 | blk_mq_ipi_complete_request(rq); | |
387 | } | |
388 | ||
30a91cb4 CH |
389 | /** |
390 | * blk_mq_complete_request - end I/O on a request | |
391 | * @rq: the request being processed | |
392 | * | |
393 | * Description: | |
394 | * Ends all I/O on a request. It does not handle partial completions. | |
395 | * The actual completion happens out-of-order, through a IPI handler. | |
396 | **/ | |
f4829a9b | 397 | void blk_mq_complete_request(struct request *rq, int error) |
30a91cb4 | 398 | { |
95f09684 JA |
399 | struct request_queue *q = rq->q; |
400 | ||
401 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 402 | return; |
f4829a9b CH |
403 | if (!blk_mark_rq_complete(rq)) { |
404 | rq->errors = error; | |
ed851860 | 405 | __blk_mq_complete_request(rq); |
f4829a9b | 406 | } |
30a91cb4 CH |
407 | } |
408 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 409 | |
973c0191 KB |
410 | int blk_mq_request_started(struct request *rq) |
411 | { | |
412 | return test_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
413 | } | |
414 | EXPORT_SYMBOL_GPL(blk_mq_request_started); | |
415 | ||
e2490073 | 416 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
417 | { |
418 | struct request_queue *q = rq->q; | |
419 | ||
420 | trace_block_rq_issue(q, rq); | |
421 | ||
742ee69b | 422 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
423 | if (unlikely(blk_bidi_rq(rq))) |
424 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 425 | |
2b8393b4 | 426 | blk_add_timer(rq); |
87ee7b11 | 427 | |
538b7534 JA |
428 | /* |
429 | * Ensure that ->deadline is visible before set the started | |
430 | * flag and clear the completed flag. | |
431 | */ | |
432 | smp_mb__before_atomic(); | |
433 | ||
87ee7b11 JA |
434 | /* |
435 | * Mark us as started and clear complete. Complete might have been | |
436 | * set if requeue raced with timeout, which then marked it as | |
437 | * complete. So be sure to clear complete again when we start | |
438 | * the request, otherwise we'll ignore the completion event. | |
439 | */ | |
4b570521 JA |
440 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
441 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
442 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
443 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
444 | |
445 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
446 | /* | |
447 | * Make sure space for the drain appears. We know we can do | |
448 | * this because max_hw_segments has been adjusted to be one | |
449 | * fewer than the device can handle. | |
450 | */ | |
451 | rq->nr_phys_segments++; | |
452 | } | |
320ae51f | 453 | } |
e2490073 | 454 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 455 | |
ed0791b2 | 456 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
457 | { |
458 | struct request_queue *q = rq->q; | |
459 | ||
460 | trace_block_rq_requeue(q, rq); | |
49f5baa5 | 461 | |
e2490073 CH |
462 | if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
463 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
464 | rq->nr_phys_segments--; | |
465 | } | |
320ae51f JA |
466 | } |
467 | ||
ed0791b2 CH |
468 | void blk_mq_requeue_request(struct request *rq) |
469 | { | |
ed0791b2 | 470 | __blk_mq_requeue_request(rq); |
ed0791b2 | 471 | |
ed0791b2 | 472 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 473 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
474 | } |
475 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
476 | ||
6fca6a61 CH |
477 | static void blk_mq_requeue_work(struct work_struct *work) |
478 | { | |
479 | struct request_queue *q = | |
480 | container_of(work, struct request_queue, requeue_work); | |
481 | LIST_HEAD(rq_list); | |
482 | struct request *rq, *next; | |
483 | unsigned long flags; | |
484 | ||
485 | spin_lock_irqsave(&q->requeue_lock, flags); | |
486 | list_splice_init(&q->requeue_list, &rq_list); | |
487 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
488 | ||
489 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
490 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
491 | continue; | |
492 | ||
493 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
494 | list_del_init(&rq->queuelist); | |
495 | blk_mq_insert_request(rq, true, false, false); | |
496 | } | |
497 | ||
498 | while (!list_empty(&rq_list)) { | |
499 | rq = list_entry(rq_list.next, struct request, queuelist); | |
500 | list_del_init(&rq->queuelist); | |
501 | blk_mq_insert_request(rq, false, false, false); | |
502 | } | |
503 | ||
8b957415 JA |
504 | /* |
505 | * Use the start variant of queue running here, so that running | |
506 | * the requeue work will kick stopped queues. | |
507 | */ | |
508 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
509 | } |
510 | ||
511 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
512 | { | |
513 | struct request_queue *q = rq->q; | |
514 | unsigned long flags; | |
515 | ||
516 | /* | |
517 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
518 | * request head insertation from the workqueue. | |
519 | */ | |
520 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
521 | ||
522 | spin_lock_irqsave(&q->requeue_lock, flags); | |
523 | if (at_head) { | |
524 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
525 | list_add(&rq->queuelist, &q->requeue_list); | |
526 | } else { | |
527 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
528 | } | |
529 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
530 | } | |
531 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
532 | ||
c68ed59f KB |
533 | void blk_mq_cancel_requeue_work(struct request_queue *q) |
534 | { | |
535 | cancel_work_sync(&q->requeue_work); | |
536 | } | |
537 | EXPORT_SYMBOL_GPL(blk_mq_cancel_requeue_work); | |
538 | ||
6fca6a61 CH |
539 | void blk_mq_kick_requeue_list(struct request_queue *q) |
540 | { | |
541 | kblockd_schedule_work(&q->requeue_work); | |
542 | } | |
543 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
544 | ||
1885b24d JA |
545 | void blk_mq_abort_requeue_list(struct request_queue *q) |
546 | { | |
547 | unsigned long flags; | |
548 | LIST_HEAD(rq_list); | |
549 | ||
550 | spin_lock_irqsave(&q->requeue_lock, flags); | |
551 | list_splice_init(&q->requeue_list, &rq_list); | |
552 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
553 | ||
554 | while (!list_empty(&rq_list)) { | |
555 | struct request *rq; | |
556 | ||
557 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
558 | list_del_init(&rq->queuelist); | |
559 | rq->errors = -EIO; | |
560 | blk_mq_end_request(rq, rq->errors); | |
561 | } | |
562 | } | |
563 | EXPORT_SYMBOL(blk_mq_abort_requeue_list); | |
564 | ||
0e62f51f JA |
565 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) |
566 | { | |
0048b483 | 567 | return tags->rqs[tag]; |
24d2f903 CH |
568 | } |
569 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
570 | ||
320ae51f | 571 | struct blk_mq_timeout_data { |
46f92d42 CH |
572 | unsigned long next; |
573 | unsigned int next_set; | |
320ae51f JA |
574 | }; |
575 | ||
90415837 | 576 | void blk_mq_rq_timed_out(struct request *req, bool reserved) |
320ae51f | 577 | { |
46f92d42 CH |
578 | struct blk_mq_ops *ops = req->q->mq_ops; |
579 | enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER; | |
87ee7b11 JA |
580 | |
581 | /* | |
582 | * We know that complete is set at this point. If STARTED isn't set | |
583 | * anymore, then the request isn't active and the "timeout" should | |
584 | * just be ignored. This can happen due to the bitflag ordering. | |
585 | * Timeout first checks if STARTED is set, and if it is, assumes | |
586 | * the request is active. But if we race with completion, then | |
587 | * we both flags will get cleared. So check here again, and ignore | |
588 | * a timeout event with a request that isn't active. | |
589 | */ | |
46f92d42 CH |
590 | if (!test_bit(REQ_ATOM_STARTED, &req->atomic_flags)) |
591 | return; | |
87ee7b11 | 592 | |
46f92d42 | 593 | if (ops->timeout) |
0152fb6b | 594 | ret = ops->timeout(req, reserved); |
46f92d42 CH |
595 | |
596 | switch (ret) { | |
597 | case BLK_EH_HANDLED: | |
598 | __blk_mq_complete_request(req); | |
599 | break; | |
600 | case BLK_EH_RESET_TIMER: | |
601 | blk_add_timer(req); | |
602 | blk_clear_rq_complete(req); | |
603 | break; | |
604 | case BLK_EH_NOT_HANDLED: | |
605 | break; | |
606 | default: | |
607 | printk(KERN_ERR "block: bad eh return: %d\n", ret); | |
608 | break; | |
609 | } | |
87ee7b11 | 610 | } |
5b3f25fc | 611 | |
81481eb4 CH |
612 | static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, |
613 | struct request *rq, void *priv, bool reserved) | |
614 | { | |
615 | struct blk_mq_timeout_data *data = priv; | |
87ee7b11 | 616 | |
eb130dbf KB |
617 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
618 | /* | |
619 | * If a request wasn't started before the queue was | |
620 | * marked dying, kill it here or it'll go unnoticed. | |
621 | */ | |
f4829a9b CH |
622 | if (unlikely(blk_queue_dying(rq->q))) |
623 | blk_mq_complete_request(rq, -EIO); | |
46f92d42 | 624 | return; |
eb130dbf | 625 | } |
5b3f25fc KB |
626 | if (rq->cmd_flags & REQ_NO_TIMEOUT) |
627 | return; | |
87ee7b11 | 628 | |
46f92d42 CH |
629 | if (time_after_eq(jiffies, rq->deadline)) { |
630 | if (!blk_mark_rq_complete(rq)) | |
0152fb6b | 631 | blk_mq_rq_timed_out(rq, reserved); |
46f92d42 CH |
632 | } else if (!data->next_set || time_after(data->next, rq->deadline)) { |
633 | data->next = rq->deadline; | |
634 | data->next_set = 1; | |
635 | } | |
87ee7b11 JA |
636 | } |
637 | ||
81481eb4 | 638 | static void blk_mq_rq_timer(unsigned long priv) |
320ae51f | 639 | { |
81481eb4 CH |
640 | struct request_queue *q = (struct request_queue *)priv; |
641 | struct blk_mq_timeout_data data = { | |
642 | .next = 0, | |
643 | .next_set = 0, | |
644 | }; | |
81481eb4 | 645 | int i; |
320ae51f | 646 | |
0bf6cd5b | 647 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &data); |
320ae51f | 648 | |
81481eb4 CH |
649 | if (data.next_set) { |
650 | data.next = blk_rq_timeout(round_jiffies_up(data.next)); | |
651 | mod_timer(&q->timeout, data.next); | |
0d2602ca | 652 | } else { |
0bf6cd5b CH |
653 | struct blk_mq_hw_ctx *hctx; |
654 | ||
f054b56c ML |
655 | queue_for_each_hw_ctx(q, hctx, i) { |
656 | /* the hctx may be unmapped, so check it here */ | |
657 | if (blk_mq_hw_queue_mapped(hctx)) | |
658 | blk_mq_tag_idle(hctx); | |
659 | } | |
0d2602ca | 660 | } |
320ae51f JA |
661 | } |
662 | ||
663 | /* | |
664 | * Reverse check our software queue for entries that we could potentially | |
665 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
666 | * too much time checking for merges. | |
667 | */ | |
668 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
669 | struct blk_mq_ctx *ctx, struct bio *bio) | |
670 | { | |
671 | struct request *rq; | |
672 | int checked = 8; | |
673 | ||
674 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
675 | int el_ret; | |
676 | ||
677 | if (!checked--) | |
678 | break; | |
679 | ||
680 | if (!blk_rq_merge_ok(rq, bio)) | |
681 | continue; | |
682 | ||
683 | el_ret = blk_try_merge(rq, bio); | |
684 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
685 | if (bio_attempt_back_merge(q, rq, bio)) { | |
686 | ctx->rq_merged++; | |
687 | return true; | |
688 | } | |
689 | break; | |
690 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
691 | if (bio_attempt_front_merge(q, rq, bio)) { | |
692 | ctx->rq_merged++; | |
693 | return true; | |
694 | } | |
695 | break; | |
696 | } | |
697 | } | |
698 | ||
699 | return false; | |
700 | } | |
701 | ||
1429d7c9 JA |
702 | /* |
703 | * Process software queues that have been marked busy, splicing them | |
704 | * to the for-dispatch | |
705 | */ | |
706 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
707 | { | |
708 | struct blk_mq_ctx *ctx; | |
709 | int i; | |
710 | ||
569fd0ce | 711 | for (i = 0; i < hctx->ctx_map.size; i++) { |
1429d7c9 JA |
712 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; |
713 | unsigned int off, bit; | |
714 | ||
715 | if (!bm->word) | |
716 | continue; | |
717 | ||
718 | bit = 0; | |
719 | off = i * hctx->ctx_map.bits_per_word; | |
720 | do { | |
721 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
722 | if (bit >= bm->depth) | |
723 | break; | |
724 | ||
725 | ctx = hctx->ctxs[bit + off]; | |
726 | clear_bit(bit, &bm->word); | |
727 | spin_lock(&ctx->lock); | |
728 | list_splice_tail_init(&ctx->rq_list, list); | |
729 | spin_unlock(&ctx->lock); | |
730 | ||
731 | bit++; | |
732 | } while (1); | |
733 | } | |
734 | } | |
735 | ||
320ae51f JA |
736 | /* |
737 | * Run this hardware queue, pulling any software queues mapped to it in. | |
738 | * Note that this function currently has various problems around ordering | |
739 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
740 | * items on the hctx->dispatch list. Ignore that for now. | |
741 | */ | |
742 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
743 | { | |
744 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
745 | struct request *rq; |
746 | LIST_HEAD(rq_list); | |
74c45052 JA |
747 | LIST_HEAD(driver_list); |
748 | struct list_head *dptr; | |
1429d7c9 | 749 | int queued; |
320ae51f | 750 | |
fd1270d5 | 751 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 752 | |
5d12f905 | 753 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
754 | return; |
755 | ||
756 | hctx->run++; | |
757 | ||
758 | /* | |
759 | * Touch any software queue that has pending entries. | |
760 | */ | |
1429d7c9 | 761 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
762 | |
763 | /* | |
764 | * If we have previous entries on our dispatch list, grab them | |
765 | * and stuff them at the front for more fair dispatch. | |
766 | */ | |
767 | if (!list_empty_careful(&hctx->dispatch)) { | |
768 | spin_lock(&hctx->lock); | |
769 | if (!list_empty(&hctx->dispatch)) | |
770 | list_splice_init(&hctx->dispatch, &rq_list); | |
771 | spin_unlock(&hctx->lock); | |
772 | } | |
773 | ||
74c45052 JA |
774 | /* |
775 | * Start off with dptr being NULL, so we start the first request | |
776 | * immediately, even if we have more pending. | |
777 | */ | |
778 | dptr = NULL; | |
779 | ||
320ae51f JA |
780 | /* |
781 | * Now process all the entries, sending them to the driver. | |
782 | */ | |
1429d7c9 | 783 | queued = 0; |
320ae51f | 784 | while (!list_empty(&rq_list)) { |
74c45052 | 785 | struct blk_mq_queue_data bd; |
320ae51f JA |
786 | int ret; |
787 | ||
788 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
789 | list_del_init(&rq->queuelist); | |
320ae51f | 790 | |
74c45052 JA |
791 | bd.rq = rq; |
792 | bd.list = dptr; | |
793 | bd.last = list_empty(&rq_list); | |
794 | ||
795 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
320ae51f JA |
796 | switch (ret) { |
797 | case BLK_MQ_RQ_QUEUE_OK: | |
798 | queued++; | |
799 | continue; | |
800 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 801 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 802 | __blk_mq_requeue_request(rq); |
320ae51f JA |
803 | break; |
804 | default: | |
805 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 806 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 807 | rq->errors = -EIO; |
c8a446ad | 808 | blk_mq_end_request(rq, rq->errors); |
320ae51f JA |
809 | break; |
810 | } | |
811 | ||
812 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
813 | break; | |
74c45052 JA |
814 | |
815 | /* | |
816 | * We've done the first request. If we have more than 1 | |
817 | * left in the list, set dptr to defer issue. | |
818 | */ | |
819 | if (!dptr && rq_list.next != rq_list.prev) | |
820 | dptr = &driver_list; | |
320ae51f JA |
821 | } |
822 | ||
823 | if (!queued) | |
824 | hctx->dispatched[0]++; | |
825 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
826 | hctx->dispatched[ilog2(queued) + 1]++; | |
827 | ||
828 | /* | |
829 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
830 | * that is where we will continue on next queue run. | |
831 | */ | |
832 | if (!list_empty(&rq_list)) { | |
833 | spin_lock(&hctx->lock); | |
834 | list_splice(&rq_list, &hctx->dispatch); | |
835 | spin_unlock(&hctx->lock); | |
9ba52e58 SL |
836 | /* |
837 | * the queue is expected stopped with BLK_MQ_RQ_QUEUE_BUSY, but | |
838 | * it's possible the queue is stopped and restarted again | |
839 | * before this. Queue restart will dispatch requests. And since | |
840 | * requests in rq_list aren't added into hctx->dispatch yet, | |
841 | * the requests in rq_list might get lost. | |
842 | * | |
843 | * blk_mq_run_hw_queue() already checks the STOPPED bit | |
844 | **/ | |
845 | blk_mq_run_hw_queue(hctx, true); | |
320ae51f JA |
846 | } |
847 | } | |
848 | ||
506e931f JA |
849 | /* |
850 | * It'd be great if the workqueue API had a way to pass | |
851 | * in a mask and had some smarts for more clever placement. | |
852 | * For now we just round-robin here, switching for every | |
853 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
854 | */ | |
855 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
856 | { | |
b657d7e6 CH |
857 | if (hctx->queue->nr_hw_queues == 1) |
858 | return WORK_CPU_UNBOUND; | |
506e931f JA |
859 | |
860 | if (--hctx->next_cpu_batch <= 0) { | |
b657d7e6 | 861 | int cpu = hctx->next_cpu, next_cpu; |
506e931f JA |
862 | |
863 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
864 | if (next_cpu >= nr_cpu_ids) | |
865 | next_cpu = cpumask_first(hctx->cpumask); | |
866 | ||
867 | hctx->next_cpu = next_cpu; | |
868 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
b657d7e6 CH |
869 | |
870 | return cpu; | |
506e931f JA |
871 | } |
872 | ||
b657d7e6 | 873 | return hctx->next_cpu; |
506e931f JA |
874 | } |
875 | ||
320ae51f JA |
876 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
877 | { | |
19c66e59 ML |
878 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state) || |
879 | !blk_mq_hw_queue_mapped(hctx))) | |
320ae51f JA |
880 | return; |
881 | ||
398205b8 | 882 | if (!async) { |
2a90d4aa PB |
883 | int cpu = get_cpu(); |
884 | if (cpumask_test_cpu(cpu, hctx->cpumask)) { | |
398205b8 | 885 | __blk_mq_run_hw_queue(hctx); |
2a90d4aa | 886 | put_cpu(); |
398205b8 PB |
887 | return; |
888 | } | |
e4043dcf | 889 | |
2a90d4aa | 890 | put_cpu(); |
e4043dcf | 891 | } |
398205b8 | 892 | |
b657d7e6 CH |
893 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
894 | &hctx->run_work, 0); | |
320ae51f JA |
895 | } |
896 | ||
b94ec296 | 897 | void blk_mq_run_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
898 | { |
899 | struct blk_mq_hw_ctx *hctx; | |
900 | int i; | |
901 | ||
902 | queue_for_each_hw_ctx(q, hctx, i) { | |
903 | if ((!blk_mq_hctx_has_pending(hctx) && | |
904 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 905 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
906 | continue; |
907 | ||
b94ec296 | 908 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
909 | } |
910 | } | |
b94ec296 | 911 | EXPORT_SYMBOL(blk_mq_run_hw_queues); |
320ae51f JA |
912 | |
913 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
914 | { | |
70f4db63 CH |
915 | cancel_delayed_work(&hctx->run_work); |
916 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
917 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
918 | } | |
919 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
920 | ||
280d45f6 CH |
921 | void blk_mq_stop_hw_queues(struct request_queue *q) |
922 | { | |
923 | struct blk_mq_hw_ctx *hctx; | |
924 | int i; | |
925 | ||
926 | queue_for_each_hw_ctx(q, hctx, i) | |
927 | blk_mq_stop_hw_queue(hctx); | |
928 | } | |
929 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
930 | ||
320ae51f JA |
931 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
932 | { | |
933 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 934 | |
0ffbce80 | 935 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
936 | } |
937 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
938 | ||
2f268556 CH |
939 | void blk_mq_start_hw_queues(struct request_queue *q) |
940 | { | |
941 | struct blk_mq_hw_ctx *hctx; | |
942 | int i; | |
943 | ||
944 | queue_for_each_hw_ctx(q, hctx, i) | |
945 | blk_mq_start_hw_queue(hctx); | |
946 | } | |
947 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
948 | ||
1b4a3258 | 949 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
950 | { |
951 | struct blk_mq_hw_ctx *hctx; | |
952 | int i; | |
953 | ||
954 | queue_for_each_hw_ctx(q, hctx, i) { | |
955 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
956 | continue; | |
957 | ||
958 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
1b4a3258 | 959 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
960 | } |
961 | } | |
962 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
963 | ||
70f4db63 | 964 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
965 | { |
966 | struct blk_mq_hw_ctx *hctx; | |
967 | ||
70f4db63 | 968 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 969 | |
320ae51f JA |
970 | __blk_mq_run_hw_queue(hctx); |
971 | } | |
972 | ||
70f4db63 CH |
973 | static void blk_mq_delay_work_fn(struct work_struct *work) |
974 | { | |
975 | struct blk_mq_hw_ctx *hctx; | |
976 | ||
977 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
978 | ||
979 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
980 | __blk_mq_run_hw_queue(hctx); | |
981 | } | |
982 | ||
983 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
984 | { | |
19c66e59 ML |
985 | if (unlikely(!blk_mq_hw_queue_mapped(hctx))) |
986 | return; | |
70f4db63 | 987 | |
b657d7e6 CH |
988 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
989 | &hctx->delay_work, msecs_to_jiffies(msecs)); | |
70f4db63 CH |
990 | } |
991 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
992 | ||
320ae51f | 993 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
72a0a36e | 994 | struct request *rq, bool at_head) |
320ae51f JA |
995 | { |
996 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
997 | ||
01b983c9 JA |
998 | trace_block_rq_insert(hctx->queue, rq); |
999 | ||
72a0a36e CH |
1000 | if (at_head) |
1001 | list_add(&rq->queuelist, &ctx->rq_list); | |
1002 | else | |
1003 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
4bb659b1 | 1004 | |
320ae51f | 1005 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
1006 | } |
1007 | ||
eeabc850 CH |
1008 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
1009 | bool async) | |
320ae51f | 1010 | { |
eeabc850 | 1011 | struct request_queue *q = rq->q; |
320ae51f | 1012 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
1013 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
1014 | ||
1015 | current_ctx = blk_mq_get_ctx(q); | |
1016 | if (!cpu_online(ctx->cpu)) | |
1017 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 1018 | |
320ae51f JA |
1019 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
1020 | ||
a57a178a CH |
1021 | spin_lock(&ctx->lock); |
1022 | __blk_mq_insert_request(hctx, rq, at_head); | |
1023 | spin_unlock(&ctx->lock); | |
320ae51f | 1024 | |
320ae51f JA |
1025 | if (run_queue) |
1026 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
1027 | |
1028 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
1029 | } |
1030 | ||
1031 | static void blk_mq_insert_requests(struct request_queue *q, | |
1032 | struct blk_mq_ctx *ctx, | |
1033 | struct list_head *list, | |
1034 | int depth, | |
1035 | bool from_schedule) | |
1036 | ||
1037 | { | |
1038 | struct blk_mq_hw_ctx *hctx; | |
1039 | struct blk_mq_ctx *current_ctx; | |
1040 | ||
1041 | trace_block_unplug(q, depth, !from_schedule); | |
1042 | ||
1043 | current_ctx = blk_mq_get_ctx(q); | |
1044 | ||
1045 | if (!cpu_online(ctx->cpu)) | |
1046 | ctx = current_ctx; | |
1047 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1048 | ||
1049 | /* | |
1050 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
1051 | * offline now | |
1052 | */ | |
1053 | spin_lock(&ctx->lock); | |
1054 | while (!list_empty(list)) { | |
1055 | struct request *rq; | |
1056 | ||
1057 | rq = list_first_entry(list, struct request, queuelist); | |
1058 | list_del_init(&rq->queuelist); | |
1059 | rq->mq_ctx = ctx; | |
72a0a36e | 1060 | __blk_mq_insert_request(hctx, rq, false); |
320ae51f JA |
1061 | } |
1062 | spin_unlock(&ctx->lock); | |
1063 | ||
320ae51f | 1064 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 1065 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
1066 | } |
1067 | ||
1068 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1069 | { | |
1070 | struct request *rqa = container_of(a, struct request, queuelist); | |
1071 | struct request *rqb = container_of(b, struct request, queuelist); | |
1072 | ||
1073 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1074 | (rqa->mq_ctx == rqb->mq_ctx && | |
1075 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1076 | } | |
1077 | ||
1078 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1079 | { | |
1080 | struct blk_mq_ctx *this_ctx; | |
1081 | struct request_queue *this_q; | |
1082 | struct request *rq; | |
1083 | LIST_HEAD(list); | |
1084 | LIST_HEAD(ctx_list); | |
1085 | unsigned int depth; | |
1086 | ||
1087 | list_splice_init(&plug->mq_list, &list); | |
1088 | ||
1089 | list_sort(NULL, &list, plug_ctx_cmp); | |
1090 | ||
1091 | this_q = NULL; | |
1092 | this_ctx = NULL; | |
1093 | depth = 0; | |
1094 | ||
1095 | while (!list_empty(&list)) { | |
1096 | rq = list_entry_rq(list.next); | |
1097 | list_del_init(&rq->queuelist); | |
1098 | BUG_ON(!rq->q); | |
1099 | if (rq->mq_ctx != this_ctx) { | |
1100 | if (this_ctx) { | |
1101 | blk_mq_insert_requests(this_q, this_ctx, | |
1102 | &ctx_list, depth, | |
1103 | from_schedule); | |
1104 | } | |
1105 | ||
1106 | this_ctx = rq->mq_ctx; | |
1107 | this_q = rq->q; | |
1108 | depth = 0; | |
1109 | } | |
1110 | ||
1111 | depth++; | |
1112 | list_add_tail(&rq->queuelist, &ctx_list); | |
1113 | } | |
1114 | ||
1115 | /* | |
1116 | * If 'this_ctx' is set, we know we have entries to complete | |
1117 | * on 'ctx_list'. Do those. | |
1118 | */ | |
1119 | if (this_ctx) { | |
1120 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1121 | from_schedule); | |
1122 | } | |
1123 | } | |
1124 | ||
1125 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1126 | { | |
1127 | init_request_from_bio(rq, bio); | |
4b570521 | 1128 | |
3ee32372 | 1129 | if (blk_do_io_stat(rq)) |
4b570521 | 1130 | blk_account_io_start(rq, 1); |
320ae51f JA |
1131 | } |
1132 | ||
274a5843 JA |
1133 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1134 | { | |
1135 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1136 | !blk_queue_nomerges(hctx->queue); | |
1137 | } | |
1138 | ||
07068d5b JA |
1139 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1140 | struct blk_mq_ctx *ctx, | |
1141 | struct request *rq, struct bio *bio) | |
320ae51f | 1142 | { |
274a5843 | 1143 | if (!hctx_allow_merges(hctx)) { |
07068d5b JA |
1144 | blk_mq_bio_to_request(rq, bio); |
1145 | spin_lock(&ctx->lock); | |
1146 | insert_rq: | |
1147 | __blk_mq_insert_request(hctx, rq, false); | |
1148 | spin_unlock(&ctx->lock); | |
1149 | return false; | |
1150 | } else { | |
274a5843 JA |
1151 | struct request_queue *q = hctx->queue; |
1152 | ||
07068d5b JA |
1153 | spin_lock(&ctx->lock); |
1154 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1155 | blk_mq_bio_to_request(rq, bio); | |
1156 | goto insert_rq; | |
1157 | } | |
320ae51f | 1158 | |
07068d5b JA |
1159 | spin_unlock(&ctx->lock); |
1160 | __blk_mq_free_request(hctx, ctx, rq); | |
1161 | return true; | |
14ec77f3 | 1162 | } |
07068d5b | 1163 | } |
14ec77f3 | 1164 | |
07068d5b JA |
1165 | struct blk_map_ctx { |
1166 | struct blk_mq_hw_ctx *hctx; | |
1167 | struct blk_mq_ctx *ctx; | |
1168 | }; | |
1169 | ||
1170 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1171 | struct bio *bio, | |
1172 | struct blk_map_ctx *data) | |
1173 | { | |
1174 | struct blk_mq_hw_ctx *hctx; | |
1175 | struct blk_mq_ctx *ctx; | |
1176 | struct request *rq; | |
1177 | int rw = bio_data_dir(bio); | |
cb96a42c | 1178 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1179 | |
bfd343aa | 1180 | if (unlikely(blk_mq_queue_enter(q, GFP_KERNEL))) { |
4246a0b6 | 1181 | bio_io_error(bio); |
07068d5b | 1182 | return NULL; |
320ae51f JA |
1183 | } |
1184 | ||
1185 | ctx = blk_mq_get_ctx(q); | |
1186 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1187 | ||
07068d5b | 1188 | if (rw_is_sync(bio->bi_rw)) |
27fbf4e8 | 1189 | rw |= REQ_SYNC; |
07068d5b | 1190 | |
320ae51f | 1191 | trace_block_getrq(q, bio, rw); |
cb96a42c ML |
1192 | blk_mq_set_alloc_data(&alloc_data, q, GFP_ATOMIC, false, ctx, |
1193 | hctx); | |
1194 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
5dee8577 | 1195 | if (unlikely(!rq)) { |
793597a6 | 1196 | __blk_mq_run_hw_queue(hctx); |
320ae51f JA |
1197 | blk_mq_put_ctx(ctx); |
1198 | trace_block_sleeprq(q, bio, rw); | |
793597a6 CH |
1199 | |
1200 | ctx = blk_mq_get_ctx(q); | |
320ae51f | 1201 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
cb96a42c ML |
1202 | blk_mq_set_alloc_data(&alloc_data, q, |
1203 | __GFP_WAIT|GFP_ATOMIC, false, ctx, hctx); | |
1204 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
1205 | ctx = alloc_data.ctx; | |
1206 | hctx = alloc_data.hctx; | |
320ae51f JA |
1207 | } |
1208 | ||
1209 | hctx->queued++; | |
07068d5b JA |
1210 | data->hctx = hctx; |
1211 | data->ctx = ctx; | |
1212 | return rq; | |
1213 | } | |
1214 | ||
f984df1f SL |
1215 | static int blk_mq_direct_issue_request(struct request *rq) |
1216 | { | |
1217 | int ret; | |
1218 | struct request_queue *q = rq->q; | |
1219 | struct blk_mq_hw_ctx *hctx = q->mq_ops->map_queue(q, | |
1220 | rq->mq_ctx->cpu); | |
1221 | struct blk_mq_queue_data bd = { | |
1222 | .rq = rq, | |
1223 | .list = NULL, | |
1224 | .last = 1 | |
1225 | }; | |
1226 | ||
1227 | /* | |
1228 | * For OK queue, we are done. For error, kill it. Any other | |
1229 | * error (busy), just add it to our list as we previously | |
1230 | * would have done | |
1231 | */ | |
1232 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
1233 | if (ret == BLK_MQ_RQ_QUEUE_OK) | |
1234 | return 0; | |
1235 | else { | |
1236 | __blk_mq_requeue_request(rq); | |
1237 | ||
1238 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1239 | rq->errors = -EIO; | |
1240 | blk_mq_end_request(rq, rq->errors); | |
1241 | return 0; | |
1242 | } | |
1243 | return -1; | |
1244 | } | |
1245 | } | |
1246 | ||
07068d5b JA |
1247 | /* |
1248 | * Multiple hardware queue variant. This will not use per-process plugs, | |
1249 | * but will attempt to bypass the hctx queueing if we can go straight to | |
1250 | * hardware for SYNC IO. | |
1251 | */ | |
1252 | static void blk_mq_make_request(struct request_queue *q, struct bio *bio) | |
1253 | { | |
1254 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1255 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1256 | struct blk_map_ctx data; | |
1257 | struct request *rq; | |
f984df1f SL |
1258 | unsigned int request_count = 0; |
1259 | struct blk_plug *plug; | |
5b3f341f | 1260 | struct request *same_queue_rq = NULL; |
07068d5b JA |
1261 | |
1262 | blk_queue_bounce(q, &bio); | |
1263 | ||
1264 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1265 | bio_io_error(bio); |
07068d5b JA |
1266 | return; |
1267 | } | |
1268 | ||
54efd50b KO |
1269 | blk_queue_split(q, &bio, q->bio_split); |
1270 | ||
f984df1f | 1271 | if (!is_flush_fua && !blk_queue_nomerges(q) && |
5b3f341f | 1272 | blk_attempt_plug_merge(q, bio, &request_count, &same_queue_rq)) |
f984df1f SL |
1273 | return; |
1274 | ||
07068d5b JA |
1275 | rq = blk_mq_map_request(q, bio, &data); |
1276 | if (unlikely(!rq)) | |
1277 | return; | |
1278 | ||
1279 | if (unlikely(is_flush_fua)) { | |
1280 | blk_mq_bio_to_request(rq, bio); | |
1281 | blk_insert_flush(rq); | |
1282 | goto run_queue; | |
1283 | } | |
1284 | ||
f984df1f | 1285 | plug = current->plug; |
e167dfb5 JA |
1286 | /* |
1287 | * If the driver supports defer issued based on 'last', then | |
1288 | * queue it up like normal since we can potentially save some | |
1289 | * CPU this way. | |
1290 | */ | |
f984df1f SL |
1291 | if (((plug && !blk_queue_nomerges(q)) || is_sync) && |
1292 | !(data.hctx->flags & BLK_MQ_F_DEFER_ISSUE)) { | |
1293 | struct request *old_rq = NULL; | |
07068d5b JA |
1294 | |
1295 | blk_mq_bio_to_request(rq, bio); | |
07068d5b JA |
1296 | |
1297 | /* | |
f984df1f SL |
1298 | * we do limited pluging. If bio can be merged, do merge. |
1299 | * Otherwise the existing request in the plug list will be | |
1300 | * issued. So the plug list will have one request at most | |
07068d5b | 1301 | */ |
f984df1f | 1302 | if (plug) { |
5b3f341f SL |
1303 | /* |
1304 | * The plug list might get flushed before this. If that | |
1305 | * happens, same_queue_rq is invalid and plug list is empty | |
1306 | **/ | |
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) | |
239ad215 | 1316 | return; |
f984df1f SL |
1317 | if (!blk_mq_direct_issue_request(old_rq)) |
1318 | return; | |
1319 | blk_mq_insert_request(old_rq, false, true, true); | |
1320 | return; | |
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 JA |
1333 | blk_mq_put_ctx(data.ctx); |
1334 | } | |
1335 | ||
1336 | /* | |
1337 | * Single hardware queue variant. This will attempt to use any per-process | |
1338 | * plug for merging and IO deferral. | |
1339 | */ | |
1340 | static void blk_sq_make_request(struct request_queue *q, struct bio *bio) | |
1341 | { | |
1342 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1343 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
e6c4438b JM |
1344 | struct blk_plug *plug; |
1345 | unsigned int request_count = 0; | |
07068d5b JA |
1346 | struct blk_map_ctx data; |
1347 | struct request *rq; | |
1348 | ||
07068d5b JA |
1349 | blk_queue_bounce(q, &bio); |
1350 | ||
1351 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1352 | bio_io_error(bio); |
07068d5b JA |
1353 | return; |
1354 | } | |
1355 | ||
54efd50b KO |
1356 | blk_queue_split(q, &bio, q->bio_split); |
1357 | ||
e6c4438b | 1358 | if (!is_flush_fua && !blk_queue_nomerges(q) && |
5b3f341f | 1359 | blk_attempt_plug_merge(q, bio, &request_count, NULL)) |
07068d5b JA |
1360 | return; |
1361 | ||
1362 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec JA |
1363 | if (unlikely(!rq)) |
1364 | return; | |
320ae51f JA |
1365 | |
1366 | if (unlikely(is_flush_fua)) { | |
1367 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1368 | blk_insert_flush(rq); |
1369 | goto run_queue; | |
1370 | } | |
1371 | ||
1372 | /* | |
1373 | * A task plug currently exists. Since this is completely lockless, | |
1374 | * utilize that to temporarily store requests until the task is | |
1375 | * either done or scheduled away. | |
1376 | */ | |
e6c4438b JM |
1377 | plug = current->plug; |
1378 | if (plug) { | |
1379 | blk_mq_bio_to_request(rq, bio); | |
1380 | if (list_empty(&plug->mq_list)) | |
1381 | trace_block_plug(q); | |
1382 | else if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
1383 | blk_flush_plug_list(plug, false); | |
1384 | trace_block_plug(q); | |
320ae51f | 1385 | } |
e6c4438b JM |
1386 | list_add_tail(&rq->queuelist, &plug->mq_list); |
1387 | blk_mq_put_ctx(data.ctx); | |
1388 | return; | |
320ae51f JA |
1389 | } |
1390 | ||
07068d5b JA |
1391 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1392 | /* | |
1393 | * For a SYNC request, send it to the hardware immediately. For | |
1394 | * an ASYNC request, just ensure that we run it later on. The | |
1395 | * latter allows for merging opportunities and more efficient | |
1396 | * dispatching. | |
1397 | */ | |
1398 | run_queue: | |
1399 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1400 | } |
1401 | ||
07068d5b | 1402 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1403 | } |
1404 | ||
1405 | /* | |
1406 | * Default mapping to a software queue, since we use one per CPU. | |
1407 | */ | |
1408 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1409 | { | |
1410 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1411 | } | |
1412 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1413 | ||
24d2f903 CH |
1414 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1415 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1416 | { |
e9b267d9 | 1417 | struct page *page; |
320ae51f | 1418 | |
24d2f903 | 1419 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1420 | int i; |
320ae51f | 1421 | |
24d2f903 CH |
1422 | for (i = 0; i < tags->nr_tags; i++) { |
1423 | if (!tags->rqs[i]) | |
e9b267d9 | 1424 | continue; |
24d2f903 CH |
1425 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1426 | hctx_idx, i); | |
a5164405 | 1427 | tags->rqs[i] = NULL; |
e9b267d9 | 1428 | } |
320ae51f | 1429 | } |
320ae51f | 1430 | |
24d2f903 CH |
1431 | while (!list_empty(&tags->page_list)) { |
1432 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1433 | list_del_init(&page->lru); |
f75782e4 CM |
1434 | /* |
1435 | * Remove kmemleak object previously allocated in | |
1436 | * blk_mq_init_rq_map(). | |
1437 | */ | |
1438 | kmemleak_free(page_address(page)); | |
320ae51f JA |
1439 | __free_pages(page, page->private); |
1440 | } | |
1441 | ||
24d2f903 | 1442 | kfree(tags->rqs); |
320ae51f | 1443 | |
24d2f903 | 1444 | blk_mq_free_tags(tags); |
320ae51f JA |
1445 | } |
1446 | ||
1447 | static size_t order_to_size(unsigned int order) | |
1448 | { | |
4ca08500 | 1449 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1450 | } |
1451 | ||
24d2f903 CH |
1452 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1453 | unsigned int hctx_idx) | |
320ae51f | 1454 | { |
24d2f903 | 1455 | struct blk_mq_tags *tags; |
320ae51f JA |
1456 | unsigned int i, j, entries_per_page, max_order = 4; |
1457 | size_t rq_size, left; | |
1458 | ||
24d2f903 | 1459 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
24391c0d SL |
1460 | set->numa_node, |
1461 | BLK_MQ_FLAG_TO_ALLOC_POLICY(set->flags)); | |
24d2f903 CH |
1462 | if (!tags) |
1463 | return NULL; | |
320ae51f | 1464 | |
24d2f903 CH |
1465 | INIT_LIST_HEAD(&tags->page_list); |
1466 | ||
a5164405 JA |
1467 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1468 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1469 | set->numa_node); | |
24d2f903 CH |
1470 | if (!tags->rqs) { |
1471 | blk_mq_free_tags(tags); | |
1472 | return NULL; | |
1473 | } | |
320ae51f JA |
1474 | |
1475 | /* | |
1476 | * rq_size is the size of the request plus driver payload, rounded | |
1477 | * to the cacheline size | |
1478 | */ | |
24d2f903 | 1479 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1480 | cache_line_size()); |
24d2f903 | 1481 | left = rq_size * set->queue_depth; |
320ae51f | 1482 | |
24d2f903 | 1483 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1484 | int this_order = max_order; |
1485 | struct page *page; | |
1486 | int to_do; | |
1487 | void *p; | |
1488 | ||
1489 | while (left < order_to_size(this_order - 1) && this_order) | |
1490 | this_order--; | |
1491 | ||
1492 | do { | |
a5164405 | 1493 | page = alloc_pages_node(set->numa_node, |
ac211175 | 1494 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO, |
a5164405 | 1495 | this_order); |
320ae51f JA |
1496 | if (page) |
1497 | break; | |
1498 | if (!this_order--) | |
1499 | break; | |
1500 | if (order_to_size(this_order) < rq_size) | |
1501 | break; | |
1502 | } while (1); | |
1503 | ||
1504 | if (!page) | |
24d2f903 | 1505 | goto fail; |
320ae51f JA |
1506 | |
1507 | page->private = this_order; | |
24d2f903 | 1508 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1509 | |
1510 | p = page_address(page); | |
f75782e4 CM |
1511 | /* |
1512 | * Allow kmemleak to scan these pages as they contain pointers | |
1513 | * to additional allocations like via ops->init_request(). | |
1514 | */ | |
1515 | kmemleak_alloc(p, order_to_size(this_order), 1, GFP_KERNEL); | |
320ae51f | 1516 | entries_per_page = order_to_size(this_order) / rq_size; |
24d2f903 | 1517 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1518 | left -= to_do * rq_size; |
1519 | for (j = 0; j < to_do; j++) { | |
24d2f903 CH |
1520 | tags->rqs[i] = p; |
1521 | if (set->ops->init_request) { | |
1522 | if (set->ops->init_request(set->driver_data, | |
1523 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1524 | set->numa_node)) { |
1525 | tags->rqs[i] = NULL; | |
24d2f903 | 1526 | goto fail; |
a5164405 | 1527 | } |
e9b267d9 CH |
1528 | } |
1529 | ||
320ae51f JA |
1530 | p += rq_size; |
1531 | i++; | |
1532 | } | |
1533 | } | |
24d2f903 | 1534 | return tags; |
320ae51f | 1535 | |
24d2f903 | 1536 | fail: |
24d2f903 CH |
1537 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1538 | return NULL; | |
320ae51f JA |
1539 | } |
1540 | ||
1429d7c9 JA |
1541 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1542 | { | |
1543 | kfree(bitmap->map); | |
1544 | } | |
1545 | ||
1546 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1547 | { | |
1548 | unsigned int bpw = 8, total, num_maps, i; | |
1549 | ||
1550 | bitmap->bits_per_word = bpw; | |
1551 | ||
1552 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1553 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1554 | GFP_KERNEL, node); | |
1555 | if (!bitmap->map) | |
1556 | return -ENOMEM; | |
1557 | ||
1429d7c9 JA |
1558 | total = nr_cpu_ids; |
1559 | for (i = 0; i < num_maps; i++) { | |
1560 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1561 | total -= bitmap->map[i].depth; | |
1562 | } | |
1563 | ||
1564 | return 0; | |
1565 | } | |
1566 | ||
484b4061 JA |
1567 | static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) |
1568 | { | |
1569 | struct request_queue *q = hctx->queue; | |
1570 | struct blk_mq_ctx *ctx; | |
1571 | LIST_HEAD(tmp); | |
1572 | ||
1573 | /* | |
1574 | * Move ctx entries to new CPU, if this one is going away. | |
1575 | */ | |
1576 | ctx = __blk_mq_get_ctx(q, cpu); | |
1577 | ||
1578 | spin_lock(&ctx->lock); | |
1579 | if (!list_empty(&ctx->rq_list)) { | |
1580 | list_splice_init(&ctx->rq_list, &tmp); | |
1581 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1582 | } | |
1583 | spin_unlock(&ctx->lock); | |
1584 | ||
1585 | if (list_empty(&tmp)) | |
1586 | return NOTIFY_OK; | |
1587 | ||
1588 | ctx = blk_mq_get_ctx(q); | |
1589 | spin_lock(&ctx->lock); | |
1590 | ||
1591 | while (!list_empty(&tmp)) { | |
1592 | struct request *rq; | |
1593 | ||
1594 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1595 | rq->mq_ctx = ctx; | |
1596 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1597 | } | |
1598 | ||
1599 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1600 | blk_mq_hctx_mark_pending(hctx, ctx); | |
1601 | ||
1602 | spin_unlock(&ctx->lock); | |
1603 | ||
1604 | blk_mq_run_hw_queue(hctx, true); | |
1605 | blk_mq_put_ctx(ctx); | |
1606 | return NOTIFY_OK; | |
1607 | } | |
1608 | ||
484b4061 JA |
1609 | static int blk_mq_hctx_notify(void *data, unsigned long action, |
1610 | unsigned int cpu) | |
1611 | { | |
1612 | struct blk_mq_hw_ctx *hctx = data; | |
1613 | ||
1614 | if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) | |
1615 | return blk_mq_hctx_cpu_offline(hctx, cpu); | |
2a34c087 ML |
1616 | |
1617 | /* | |
1618 | * In case of CPU online, tags may be reallocated | |
1619 | * in blk_mq_map_swqueue() after mapping is updated. | |
1620 | */ | |
484b4061 JA |
1621 | |
1622 | return NOTIFY_OK; | |
1623 | } | |
1624 | ||
c3b4afca | 1625 | /* hctx->ctxs will be freed in queue's release handler */ |
08e98fc6 ML |
1626 | static void blk_mq_exit_hctx(struct request_queue *q, |
1627 | struct blk_mq_tag_set *set, | |
1628 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
1629 | { | |
f70ced09 ML |
1630 | unsigned flush_start_tag = set->queue_depth; |
1631 | ||
08e98fc6 ML |
1632 | blk_mq_tag_idle(hctx); |
1633 | ||
f70ced09 ML |
1634 | if (set->ops->exit_request) |
1635 | set->ops->exit_request(set->driver_data, | |
1636 | hctx->fq->flush_rq, hctx_idx, | |
1637 | flush_start_tag + hctx_idx); | |
1638 | ||
08e98fc6 ML |
1639 | if (set->ops->exit_hctx) |
1640 | set->ops->exit_hctx(hctx, hctx_idx); | |
1641 | ||
1642 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
f70ced09 | 1643 | blk_free_flush_queue(hctx->fq); |
08e98fc6 ML |
1644 | blk_mq_free_bitmap(&hctx->ctx_map); |
1645 | } | |
1646 | ||
624dbe47 ML |
1647 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1648 | struct blk_mq_tag_set *set, int nr_queue) | |
1649 | { | |
1650 | struct blk_mq_hw_ctx *hctx; | |
1651 | unsigned int i; | |
1652 | ||
1653 | queue_for_each_hw_ctx(q, hctx, i) { | |
1654 | if (i == nr_queue) | |
1655 | break; | |
08e98fc6 | 1656 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 1657 | } |
624dbe47 ML |
1658 | } |
1659 | ||
1660 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1661 | struct blk_mq_tag_set *set) | |
1662 | { | |
1663 | struct blk_mq_hw_ctx *hctx; | |
1664 | unsigned int i; | |
1665 | ||
e09aae7e | 1666 | queue_for_each_hw_ctx(q, hctx, i) |
624dbe47 | 1667 | free_cpumask_var(hctx->cpumask); |
624dbe47 ML |
1668 | } |
1669 | ||
08e98fc6 ML |
1670 | static int blk_mq_init_hctx(struct request_queue *q, |
1671 | struct blk_mq_tag_set *set, | |
1672 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 1673 | { |
08e98fc6 | 1674 | int node; |
f70ced09 | 1675 | unsigned flush_start_tag = set->queue_depth; |
08e98fc6 ML |
1676 | |
1677 | node = hctx->numa_node; | |
1678 | if (node == NUMA_NO_NODE) | |
1679 | node = hctx->numa_node = set->numa_node; | |
1680 | ||
1681 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); | |
1682 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
1683 | spin_lock_init(&hctx->lock); | |
1684 | INIT_LIST_HEAD(&hctx->dispatch); | |
1685 | hctx->queue = q; | |
1686 | hctx->queue_num = hctx_idx; | |
1687 | hctx->flags = set->flags; | |
08e98fc6 ML |
1688 | |
1689 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1690 | blk_mq_hctx_notify, hctx); | |
1691 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1692 | ||
1693 | hctx->tags = set->tags[hctx_idx]; | |
320ae51f JA |
1694 | |
1695 | /* | |
08e98fc6 ML |
1696 | * Allocate space for all possible cpus to avoid allocation at |
1697 | * runtime | |
320ae51f | 1698 | */ |
08e98fc6 ML |
1699 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), |
1700 | GFP_KERNEL, node); | |
1701 | if (!hctx->ctxs) | |
1702 | goto unregister_cpu_notifier; | |
320ae51f | 1703 | |
08e98fc6 ML |
1704 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
1705 | goto free_ctxs; | |
320ae51f | 1706 | |
08e98fc6 | 1707 | hctx->nr_ctx = 0; |
320ae51f | 1708 | |
08e98fc6 ML |
1709 | if (set->ops->init_hctx && |
1710 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
1711 | goto free_bitmap; | |
320ae51f | 1712 | |
f70ced09 ML |
1713 | hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); |
1714 | if (!hctx->fq) | |
1715 | goto exit_hctx; | |
320ae51f | 1716 | |
f70ced09 ML |
1717 | if (set->ops->init_request && |
1718 | set->ops->init_request(set->driver_data, | |
1719 | hctx->fq->flush_rq, hctx_idx, | |
1720 | flush_start_tag + hctx_idx, node)) | |
1721 | goto free_fq; | |
320ae51f | 1722 | |
08e98fc6 | 1723 | return 0; |
320ae51f | 1724 | |
f70ced09 ML |
1725 | free_fq: |
1726 | kfree(hctx->fq); | |
1727 | exit_hctx: | |
1728 | if (set->ops->exit_hctx) | |
1729 | set->ops->exit_hctx(hctx, hctx_idx); | |
08e98fc6 ML |
1730 | free_bitmap: |
1731 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1732 | free_ctxs: | |
1733 | kfree(hctx->ctxs); | |
1734 | unregister_cpu_notifier: | |
1735 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
320ae51f | 1736 | |
08e98fc6 ML |
1737 | return -1; |
1738 | } | |
320ae51f | 1739 | |
08e98fc6 ML |
1740 | static int blk_mq_init_hw_queues(struct request_queue *q, |
1741 | struct blk_mq_tag_set *set) | |
1742 | { | |
1743 | struct blk_mq_hw_ctx *hctx; | |
1744 | unsigned int i; | |
320ae51f | 1745 | |
08e98fc6 ML |
1746 | /* |
1747 | * Initialize hardware queues | |
1748 | */ | |
1749 | queue_for_each_hw_ctx(q, hctx, i) { | |
1750 | if (blk_mq_init_hctx(q, set, hctx, i)) | |
320ae51f JA |
1751 | break; |
1752 | } | |
1753 | ||
1754 | if (i == q->nr_hw_queues) | |
1755 | return 0; | |
1756 | ||
1757 | /* | |
1758 | * Init failed | |
1759 | */ | |
624dbe47 | 1760 | blk_mq_exit_hw_queues(q, set, i); |
320ae51f JA |
1761 | |
1762 | return 1; | |
1763 | } | |
1764 | ||
1765 | static void blk_mq_init_cpu_queues(struct request_queue *q, | |
1766 | unsigned int nr_hw_queues) | |
1767 | { | |
1768 | unsigned int i; | |
1769 | ||
1770 | for_each_possible_cpu(i) { | |
1771 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1772 | struct blk_mq_hw_ctx *hctx; | |
1773 | ||
1774 | memset(__ctx, 0, sizeof(*__ctx)); | |
1775 | __ctx->cpu = i; | |
1776 | spin_lock_init(&__ctx->lock); | |
1777 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1778 | __ctx->queue = q; | |
1779 | ||
1780 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1781 | if (!cpu_online(i)) |
1782 | continue; | |
1783 | ||
e4043dcf | 1784 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1785 | |
320ae51f JA |
1786 | /* |
1787 | * Set local node, IFF we have more than one hw queue. If | |
1788 | * not, we remain on the home node of the device | |
1789 | */ | |
1790 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
1791 | hctx->numa_node = cpu_to_node(i); | |
1792 | } | |
1793 | } | |
1794 | ||
5778322e AM |
1795 | static void blk_mq_map_swqueue(struct request_queue *q, |
1796 | const struct cpumask *online_mask) | |
320ae51f JA |
1797 | { |
1798 | unsigned int i; | |
1799 | struct blk_mq_hw_ctx *hctx; | |
1800 | struct blk_mq_ctx *ctx; | |
2a34c087 | 1801 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 1802 | |
60de074b AM |
1803 | /* |
1804 | * Avoid others reading imcomplete hctx->cpumask through sysfs | |
1805 | */ | |
1806 | mutex_lock(&q->sysfs_lock); | |
1807 | ||
320ae51f | 1808 | queue_for_each_hw_ctx(q, hctx, i) { |
e4043dcf | 1809 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1810 | hctx->nr_ctx = 0; |
1811 | } | |
1812 | ||
1813 | /* | |
1814 | * Map software to hardware queues | |
1815 | */ | |
1816 | queue_for_each_ctx(q, ctx, i) { | |
1817 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
5778322e | 1818 | if (!cpumask_test_cpu(i, online_mask)) |
e4043dcf JA |
1819 | continue; |
1820 | ||
320ae51f | 1821 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1822 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1823 | ctx->index_hw = hctx->nr_ctx; |
1824 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1825 | } | |
506e931f | 1826 | |
60de074b AM |
1827 | mutex_unlock(&q->sysfs_lock); |
1828 | ||
506e931f | 1829 | queue_for_each_hw_ctx(q, hctx, i) { |
889fa31f CY |
1830 | struct blk_mq_ctxmap *map = &hctx->ctx_map; |
1831 | ||
484b4061 | 1832 | /* |
a68aafa5 JA |
1833 | * If no software queues are mapped to this hardware queue, |
1834 | * disable it and free the request entries. | |
484b4061 JA |
1835 | */ |
1836 | if (!hctx->nr_ctx) { | |
484b4061 JA |
1837 | if (set->tags[i]) { |
1838 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1839 | set->tags[i] = NULL; | |
484b4061 | 1840 | } |
2a34c087 | 1841 | hctx->tags = NULL; |
484b4061 JA |
1842 | continue; |
1843 | } | |
1844 | ||
2a34c087 ML |
1845 | /* unmapped hw queue can be remapped after CPU topo changed */ |
1846 | if (!set->tags[i]) | |
1847 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1848 | hctx->tags = set->tags[i]; | |
1849 | WARN_ON(!hctx->tags); | |
1850 | ||
889fa31f CY |
1851 | /* |
1852 | * Set the map size to the number of mapped software queues. | |
1853 | * This is more accurate and more efficient than looping | |
1854 | * over all possibly mapped software queues. | |
1855 | */ | |
569fd0ce | 1856 | map->size = DIV_ROUND_UP(hctx->nr_ctx, map->bits_per_word); |
889fa31f | 1857 | |
484b4061 JA |
1858 | /* |
1859 | * Initialize batch roundrobin counts | |
1860 | */ | |
506e931f JA |
1861 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1862 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1863 | } | |
1356aae0 AM |
1864 | |
1865 | queue_for_each_ctx(q, ctx, i) { | |
5778322e | 1866 | if (!cpumask_test_cpu(i, online_mask)) |
1356aae0 AM |
1867 | continue; |
1868 | ||
1869 | hctx = q->mq_ops->map_queue(q, i); | |
1870 | cpumask_set_cpu(i, hctx->tags->cpumask); | |
1871 | } | |
320ae51f JA |
1872 | } |
1873 | ||
0d2602ca JA |
1874 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |
1875 | { | |
1876 | struct blk_mq_hw_ctx *hctx; | |
1877 | struct request_queue *q; | |
1878 | bool shared; | |
1879 | int i; | |
1880 | ||
1881 | if (set->tag_list.next == set->tag_list.prev) | |
1882 | shared = false; | |
1883 | else | |
1884 | shared = true; | |
1885 | ||
1886 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1887 | blk_mq_freeze_queue(q); | |
1888 | ||
1889 | queue_for_each_hw_ctx(q, hctx, i) { | |
1890 | if (shared) | |
1891 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1892 | else | |
1893 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1894 | } | |
1895 | blk_mq_unfreeze_queue(q); | |
1896 | } | |
1897 | } | |
1898 | ||
1899 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1900 | { | |
1901 | struct blk_mq_tag_set *set = q->tag_set; | |
1902 | ||
0d2602ca JA |
1903 | mutex_lock(&set->tag_list_lock); |
1904 | list_del_init(&q->tag_set_list); | |
1905 | blk_mq_update_tag_set_depth(set); | |
1906 | mutex_unlock(&set->tag_list_lock); | |
0d2602ca JA |
1907 | } |
1908 | ||
1909 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1910 | struct request_queue *q) | |
1911 | { | |
1912 | q->tag_set = set; | |
1913 | ||
1914 | mutex_lock(&set->tag_list_lock); | |
1915 | list_add_tail(&q->tag_set_list, &set->tag_list); | |
1916 | blk_mq_update_tag_set_depth(set); | |
1917 | mutex_unlock(&set->tag_list_lock); | |
1918 | } | |
1919 | ||
e09aae7e ML |
1920 | /* |
1921 | * It is the actual release handler for mq, but we do it from | |
1922 | * request queue's release handler for avoiding use-after-free | |
1923 | * and headache because q->mq_kobj shouldn't have been introduced, | |
1924 | * but we can't group ctx/kctx kobj without it. | |
1925 | */ | |
1926 | void blk_mq_release(struct request_queue *q) | |
1927 | { | |
1928 | struct blk_mq_hw_ctx *hctx; | |
1929 | unsigned int i; | |
1930 | ||
1931 | /* hctx kobj stays in hctx */ | |
c3b4afca ML |
1932 | queue_for_each_hw_ctx(q, hctx, i) { |
1933 | if (!hctx) | |
1934 | continue; | |
1935 | kfree(hctx->ctxs); | |
e09aae7e | 1936 | kfree(hctx); |
c3b4afca | 1937 | } |
e09aae7e | 1938 | |
a723bab3 AM |
1939 | kfree(q->mq_map); |
1940 | q->mq_map = NULL; | |
1941 | ||
e09aae7e ML |
1942 | kfree(q->queue_hw_ctx); |
1943 | ||
1944 | /* ctx kobj stays in queue_ctx */ | |
1945 | free_percpu(q->queue_ctx); | |
1946 | } | |
1947 | ||
24d2f903 | 1948 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
b62c21b7 MS |
1949 | { |
1950 | struct request_queue *uninit_q, *q; | |
1951 | ||
1952 | uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); | |
1953 | if (!uninit_q) | |
1954 | return ERR_PTR(-ENOMEM); | |
1955 | ||
1956 | q = blk_mq_init_allocated_queue(set, uninit_q); | |
1957 | if (IS_ERR(q)) | |
1958 | blk_cleanup_queue(uninit_q); | |
1959 | ||
1960 | return q; | |
1961 | } | |
1962 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1963 | ||
1964 | struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, | |
1965 | struct request_queue *q) | |
320ae51f JA |
1966 | { |
1967 | struct blk_mq_hw_ctx **hctxs; | |
e6cdb092 | 1968 | struct blk_mq_ctx __percpu *ctx; |
f14bbe77 | 1969 | unsigned int *map; |
320ae51f JA |
1970 | int i; |
1971 | ||
320ae51f JA |
1972 | ctx = alloc_percpu(struct blk_mq_ctx); |
1973 | if (!ctx) | |
1974 | return ERR_PTR(-ENOMEM); | |
1975 | ||
24d2f903 CH |
1976 | hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, |
1977 | set->numa_node); | |
320ae51f JA |
1978 | |
1979 | if (!hctxs) | |
1980 | goto err_percpu; | |
1981 | ||
f14bbe77 JA |
1982 | map = blk_mq_make_queue_map(set); |
1983 | if (!map) | |
1984 | goto err_map; | |
1985 | ||
24d2f903 | 1986 | for (i = 0; i < set->nr_hw_queues; i++) { |
f14bbe77 JA |
1987 | int node = blk_mq_hw_queue_to_node(map, i); |
1988 | ||
cdef54dd CH |
1989 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1990 | GFP_KERNEL, node); | |
320ae51f JA |
1991 | if (!hctxs[i]) |
1992 | goto err_hctxs; | |
1993 | ||
a86073e4 JA |
1994 | if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, |
1995 | node)) | |
e4043dcf JA |
1996 | goto err_hctxs; |
1997 | ||
0d2602ca | 1998 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1999 | hctxs[i]->numa_node = node; |
320ae51f JA |
2000 | hctxs[i]->queue_num = i; |
2001 | } | |
2002 | ||
17497acb TH |
2003 | /* |
2004 | * Init percpu_ref in atomic mode so that it's faster to shutdown. | |
2005 | * See blk_register_queue() for details. | |
2006 | */ | |
a34375ef | 2007 | if (percpu_ref_init(&q->mq_usage_counter, blk_mq_usage_counter_release, |
17497acb | 2008 | PERCPU_REF_INIT_ATOMIC, GFP_KERNEL)) |
b62c21b7 | 2009 | goto err_hctxs; |
3d2936f4 | 2010 | |
320ae51f | 2011 | setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); |
e56f698b | 2012 | blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); |
320ae51f JA |
2013 | |
2014 | q->nr_queues = nr_cpu_ids; | |
24d2f903 | 2015 | q->nr_hw_queues = set->nr_hw_queues; |
f14bbe77 | 2016 | q->mq_map = map; |
320ae51f JA |
2017 | |
2018 | q->queue_ctx = ctx; | |
2019 | q->queue_hw_ctx = hctxs; | |
2020 | ||
24d2f903 | 2021 | q->mq_ops = set->ops; |
94eddfbe | 2022 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 2023 | |
05f1dd53 JA |
2024 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
2025 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
2026 | ||
1be036e9 CH |
2027 | q->sg_reserved_size = INT_MAX; |
2028 | ||
6fca6a61 CH |
2029 | INIT_WORK(&q->requeue_work, blk_mq_requeue_work); |
2030 | INIT_LIST_HEAD(&q->requeue_list); | |
2031 | spin_lock_init(&q->requeue_lock); | |
2032 | ||
07068d5b JA |
2033 | if (q->nr_hw_queues > 1) |
2034 | blk_queue_make_request(q, blk_mq_make_request); | |
2035 | else | |
2036 | blk_queue_make_request(q, blk_sq_make_request); | |
2037 | ||
eba71768 JA |
2038 | /* |
2039 | * Do this after blk_queue_make_request() overrides it... | |
2040 | */ | |
2041 | q->nr_requests = set->queue_depth; | |
2042 | ||
24d2f903 CH |
2043 | if (set->ops->complete) |
2044 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 2045 | |
24d2f903 | 2046 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 2047 | |
24d2f903 | 2048 | if (blk_mq_init_hw_queues(q, set)) |
b62c21b7 | 2049 | goto err_hctxs; |
18741986 | 2050 | |
5778322e | 2051 | get_online_cpus(); |
320ae51f | 2052 | mutex_lock(&all_q_mutex); |
320ae51f | 2053 | |
4593fdbe | 2054 | list_add_tail(&q->all_q_node, &all_q_list); |
0d2602ca | 2055 | blk_mq_add_queue_tag_set(set, q); |
5778322e | 2056 | blk_mq_map_swqueue(q, cpu_online_mask); |
0d2602ca | 2057 | |
4593fdbe | 2058 | mutex_unlock(&all_q_mutex); |
5778322e | 2059 | put_online_cpus(); |
484b4061 | 2060 | |
320ae51f | 2061 | return q; |
18741986 | 2062 | |
320ae51f | 2063 | err_hctxs: |
f14bbe77 | 2064 | kfree(map); |
24d2f903 | 2065 | for (i = 0; i < set->nr_hw_queues; i++) { |
320ae51f JA |
2066 | if (!hctxs[i]) |
2067 | break; | |
e4043dcf | 2068 | free_cpumask_var(hctxs[i]->cpumask); |
cdef54dd | 2069 | kfree(hctxs[i]); |
320ae51f | 2070 | } |
f14bbe77 | 2071 | err_map: |
320ae51f JA |
2072 | kfree(hctxs); |
2073 | err_percpu: | |
2074 | free_percpu(ctx); | |
2075 | return ERR_PTR(-ENOMEM); | |
2076 | } | |
b62c21b7 | 2077 | EXPORT_SYMBOL(blk_mq_init_allocated_queue); |
320ae51f JA |
2078 | |
2079 | void blk_mq_free_queue(struct request_queue *q) | |
2080 | { | |
624dbe47 | 2081 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 2082 | |
0e626368 AM |
2083 | mutex_lock(&all_q_mutex); |
2084 | list_del_init(&q->all_q_node); | |
2085 | mutex_unlock(&all_q_mutex); | |
2086 | ||
0d2602ca JA |
2087 | blk_mq_del_queue_tag_set(q); |
2088 | ||
624dbe47 ML |
2089 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
2090 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 2091 | |
add703fd | 2092 | percpu_ref_exit(&q->mq_usage_counter); |
320ae51f | 2093 | } |
320ae51f JA |
2094 | |
2095 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
5778322e AM |
2096 | static void blk_mq_queue_reinit(struct request_queue *q, |
2097 | const struct cpumask *online_mask) | |
320ae51f | 2098 | { |
4ecd4fef | 2099 | WARN_ON_ONCE(!atomic_read(&q->mq_freeze_depth)); |
320ae51f | 2100 | |
67aec14c JA |
2101 | blk_mq_sysfs_unregister(q); |
2102 | ||
5778322e | 2103 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues, online_mask); |
320ae51f JA |
2104 | |
2105 | /* | |
2106 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
2107 | * we should change hctx numa_node according to new topology (this | |
2108 | * involves free and re-allocate memory, worthy doing?) | |
2109 | */ | |
2110 | ||
5778322e | 2111 | blk_mq_map_swqueue(q, online_mask); |
320ae51f | 2112 | |
67aec14c | 2113 | blk_mq_sysfs_register(q); |
320ae51f JA |
2114 | } |
2115 | ||
f618ef7c PG |
2116 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
2117 | unsigned long action, void *hcpu) | |
320ae51f JA |
2118 | { |
2119 | struct request_queue *q; | |
5778322e AM |
2120 | int cpu = (unsigned long)hcpu; |
2121 | /* | |
2122 | * New online cpumask which is going to be set in this hotplug event. | |
2123 | * Declare this cpumasks as global as cpu-hotplug operation is invoked | |
2124 | * one-by-one and dynamically allocating this could result in a failure. | |
2125 | */ | |
2126 | static struct cpumask online_new; | |
320ae51f JA |
2127 | |
2128 | /* | |
5778322e AM |
2129 | * Before hotadded cpu starts handling requests, new mappings must |
2130 | * be established. Otherwise, these requests in hw queue might | |
2131 | * never be dispatched. | |
2132 | * | |
2133 | * For example, there is a single hw queue (hctx) and two CPU queues | |
2134 | * (ctx0 for CPU0, and ctx1 for CPU1). | |
2135 | * | |
2136 | * Now CPU1 is just onlined and a request is inserted into | |
2137 | * ctx1->rq_list and set bit0 in pending bitmap as ctx1->index_hw is | |
2138 | * still zero. | |
2139 | * | |
2140 | * And then while running hw queue, flush_busy_ctxs() finds bit0 is | |
2141 | * set in pending bitmap and tries to retrieve requests in | |
2142 | * hctx->ctxs[0]->rq_list. But htx->ctxs[0] is a pointer to ctx0, | |
2143 | * so the request in ctx1->rq_list is ignored. | |
320ae51f | 2144 | */ |
5778322e AM |
2145 | switch (action & ~CPU_TASKS_FROZEN) { |
2146 | case CPU_DEAD: | |
2147 | case CPU_UP_CANCELED: | |
2148 | cpumask_copy(&online_new, cpu_online_mask); | |
2149 | break; | |
2150 | case CPU_UP_PREPARE: | |
2151 | cpumask_copy(&online_new, cpu_online_mask); | |
2152 | cpumask_set_cpu(cpu, &online_new); | |
2153 | break; | |
2154 | default: | |
320ae51f | 2155 | return NOTIFY_OK; |
5778322e | 2156 | } |
320ae51f JA |
2157 | |
2158 | mutex_lock(&all_q_mutex); | |
f3af020b TH |
2159 | |
2160 | /* | |
2161 | * We need to freeze and reinit all existing queues. Freezing | |
2162 | * involves synchronous wait for an RCU grace period and doing it | |
2163 | * one by one may take a long time. Start freezing all queues in | |
2164 | * one swoop and then wait for the completions so that freezing can | |
2165 | * take place in parallel. | |
2166 | */ | |
2167 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2168 | blk_mq_freeze_queue_start(q); | |
f054b56c | 2169 | list_for_each_entry(q, &all_q_list, all_q_node) { |
f3af020b TH |
2170 | blk_mq_freeze_queue_wait(q); |
2171 | ||
f054b56c ML |
2172 | /* |
2173 | * timeout handler can't touch hw queue during the | |
2174 | * reinitialization | |
2175 | */ | |
2176 | del_timer_sync(&q->timeout); | |
2177 | } | |
2178 | ||
320ae51f | 2179 | list_for_each_entry(q, &all_q_list, all_q_node) |
5778322e | 2180 | blk_mq_queue_reinit(q, &online_new); |
f3af020b TH |
2181 | |
2182 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2183 | blk_mq_unfreeze_queue(q); | |
2184 | ||
320ae51f JA |
2185 | mutex_unlock(&all_q_mutex); |
2186 | return NOTIFY_OK; | |
2187 | } | |
2188 | ||
a5164405 JA |
2189 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
2190 | { | |
2191 | int i; | |
2192 | ||
2193 | for (i = 0; i < set->nr_hw_queues; i++) { | |
2194 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
2195 | if (!set->tags[i]) | |
2196 | goto out_unwind; | |
2197 | } | |
2198 | ||
2199 | return 0; | |
2200 | ||
2201 | out_unwind: | |
2202 | while (--i >= 0) | |
2203 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2204 | ||
a5164405 JA |
2205 | return -ENOMEM; |
2206 | } | |
2207 | ||
2208 | /* | |
2209 | * Allocate the request maps associated with this tag_set. Note that this | |
2210 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
2211 | * will be updated to reflect the allocated depth. | |
2212 | */ | |
2213 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
2214 | { | |
2215 | unsigned int depth; | |
2216 | int err; | |
2217 | ||
2218 | depth = set->queue_depth; | |
2219 | do { | |
2220 | err = __blk_mq_alloc_rq_maps(set); | |
2221 | if (!err) | |
2222 | break; | |
2223 | ||
2224 | set->queue_depth >>= 1; | |
2225 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
2226 | err = -ENOMEM; | |
2227 | break; | |
2228 | } | |
2229 | } while (set->queue_depth); | |
2230 | ||
2231 | if (!set->queue_depth || err) { | |
2232 | pr_err("blk-mq: failed to allocate request map\n"); | |
2233 | return -ENOMEM; | |
2234 | } | |
2235 | ||
2236 | if (depth != set->queue_depth) | |
2237 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2238 | depth, set->queue_depth); | |
2239 | ||
2240 | return 0; | |
2241 | } | |
2242 | ||
f26cdc85 KB |
2243 | struct cpumask *blk_mq_tags_cpumask(struct blk_mq_tags *tags) |
2244 | { | |
2245 | return tags->cpumask; | |
2246 | } | |
2247 | EXPORT_SYMBOL_GPL(blk_mq_tags_cpumask); | |
2248 | ||
a4391c64 JA |
2249 | /* |
2250 | * Alloc a tag set to be associated with one or more request queues. | |
2251 | * May fail with EINVAL for various error conditions. May adjust the | |
2252 | * requested depth down, if if it too large. In that case, the set | |
2253 | * value will be stored in set->queue_depth. | |
2254 | */ | |
24d2f903 CH |
2255 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2256 | { | |
205fb5f5 BVA |
2257 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
2258 | ||
24d2f903 CH |
2259 | if (!set->nr_hw_queues) |
2260 | return -EINVAL; | |
a4391c64 | 2261 | if (!set->queue_depth) |
24d2f903 CH |
2262 | return -EINVAL; |
2263 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2264 | return -EINVAL; | |
2265 | ||
f9018ac9 | 2266 | if (!set->ops->queue_rq || !set->ops->map_queue) |
24d2f903 CH |
2267 | return -EINVAL; |
2268 | ||
a4391c64 JA |
2269 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2270 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2271 | BLK_MQ_MAX_DEPTH); | |
2272 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2273 | } | |
24d2f903 | 2274 | |
6637fadf SL |
2275 | /* |
2276 | * If a crashdump is active, then we are potentially in a very | |
2277 | * memory constrained environment. Limit us to 1 queue and | |
2278 | * 64 tags to prevent using too much memory. | |
2279 | */ | |
2280 | if (is_kdump_kernel()) { | |
2281 | set->nr_hw_queues = 1; | |
2282 | set->queue_depth = min(64U, set->queue_depth); | |
2283 | } | |
2284 | ||
48479005 ML |
2285 | set->tags = kmalloc_node(set->nr_hw_queues * |
2286 | sizeof(struct blk_mq_tags *), | |
24d2f903 CH |
2287 | GFP_KERNEL, set->numa_node); |
2288 | if (!set->tags) | |
a5164405 | 2289 | return -ENOMEM; |
24d2f903 | 2290 | |
a5164405 JA |
2291 | if (blk_mq_alloc_rq_maps(set)) |
2292 | goto enomem; | |
24d2f903 | 2293 | |
0d2602ca JA |
2294 | mutex_init(&set->tag_list_lock); |
2295 | INIT_LIST_HEAD(&set->tag_list); | |
2296 | ||
24d2f903 | 2297 | return 0; |
a5164405 | 2298 | enomem: |
5676e7b6 RE |
2299 | kfree(set->tags); |
2300 | set->tags = NULL; | |
24d2f903 CH |
2301 | return -ENOMEM; |
2302 | } | |
2303 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2304 | ||
2305 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2306 | { | |
2307 | int i; | |
2308 | ||
484b4061 | 2309 | for (i = 0; i < set->nr_hw_queues; i++) { |
f26cdc85 | 2310 | if (set->tags[i]) { |
484b4061 | 2311 | blk_mq_free_rq_map(set, set->tags[i], i); |
f26cdc85 KB |
2312 | free_cpumask_var(set->tags[i]->cpumask); |
2313 | } | |
484b4061 JA |
2314 | } |
2315 | ||
981bd189 | 2316 | kfree(set->tags); |
5676e7b6 | 2317 | set->tags = NULL; |
24d2f903 CH |
2318 | } |
2319 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2320 | ||
e3a2b3f9 JA |
2321 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2322 | { | |
2323 | struct blk_mq_tag_set *set = q->tag_set; | |
2324 | struct blk_mq_hw_ctx *hctx; | |
2325 | int i, ret; | |
2326 | ||
2327 | if (!set || nr > set->queue_depth) | |
2328 | return -EINVAL; | |
2329 | ||
2330 | ret = 0; | |
2331 | queue_for_each_hw_ctx(q, hctx, i) { | |
2332 | ret = blk_mq_tag_update_depth(hctx->tags, nr); | |
2333 | if (ret) | |
2334 | break; | |
2335 | } | |
2336 | ||
2337 | if (!ret) | |
2338 | q->nr_requests = nr; | |
2339 | ||
2340 | return ret; | |
2341 | } | |
2342 | ||
676141e4 JA |
2343 | void blk_mq_disable_hotplug(void) |
2344 | { | |
2345 | mutex_lock(&all_q_mutex); | |
2346 | } | |
2347 | ||
2348 | void blk_mq_enable_hotplug(void) | |
2349 | { | |
2350 | mutex_unlock(&all_q_mutex); | |
2351 | } | |
2352 | ||
320ae51f JA |
2353 | static int __init blk_mq_init(void) |
2354 | { | |
320ae51f JA |
2355 | blk_mq_cpu_init(); |
2356 | ||
add703fd | 2357 | hotcpu_notifier(blk_mq_queue_reinit_notify, 0); |
320ae51f JA |
2358 | |
2359 | return 0; | |
2360 | } | |
2361 | subsys_initcall(blk_mq_init); |