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 | 91 | ret = wait_event_interruptible(q->mq_freeze_wq, |
4ecd4fef CH |
92 | !atomic_read(&q->mq_freeze_depth) || |
93 | blk_queue_dying(q)); | |
add703fd TH |
94 | if (blk_queue_dying(q)) |
95 | return -ENODEV; | |
96 | if (ret) | |
97 | return ret; | |
98 | } | |
320ae51f JA |
99 | } |
100 | ||
101 | static void blk_mq_queue_exit(struct request_queue *q) | |
102 | { | |
add703fd TH |
103 | percpu_ref_put(&q->mq_usage_counter); |
104 | } | |
105 | ||
106 | static void blk_mq_usage_counter_release(struct percpu_ref *ref) | |
107 | { | |
108 | struct request_queue *q = | |
109 | container_of(ref, struct request_queue, mq_usage_counter); | |
110 | ||
111 | wake_up_all(&q->mq_freeze_wq); | |
320ae51f JA |
112 | } |
113 | ||
b4c6a028 | 114 | void blk_mq_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 115 | { |
4ecd4fef | 116 | int freeze_depth; |
cddd5d17 | 117 | |
4ecd4fef CH |
118 | freeze_depth = atomic_inc_return(&q->mq_freeze_depth); |
119 | if (freeze_depth == 1) { | |
9eca8046 | 120 | percpu_ref_kill(&q->mq_usage_counter); |
b94ec296 | 121 | blk_mq_run_hw_queues(q, false); |
cddd5d17 | 122 | } |
f3af020b | 123 | } |
b4c6a028 | 124 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start); |
f3af020b TH |
125 | |
126 | static void blk_mq_freeze_queue_wait(struct request_queue *q) | |
127 | { | |
add703fd | 128 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); |
43a5e4e2 ML |
129 | } |
130 | ||
f3af020b TH |
131 | /* |
132 | * Guarantee no request is in use, so we can change any data structure of | |
133 | * the queue afterward. | |
134 | */ | |
135 | void blk_mq_freeze_queue(struct request_queue *q) | |
136 | { | |
137 | blk_mq_freeze_queue_start(q); | |
138 | blk_mq_freeze_queue_wait(q); | |
139 | } | |
c761d96b | 140 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue); |
f3af020b | 141 | |
b4c6a028 | 142 | void blk_mq_unfreeze_queue(struct request_queue *q) |
320ae51f | 143 | { |
4ecd4fef | 144 | int freeze_depth; |
320ae51f | 145 | |
4ecd4fef CH |
146 | freeze_depth = atomic_dec_return(&q->mq_freeze_depth); |
147 | WARN_ON_ONCE(freeze_depth < 0); | |
148 | if (!freeze_depth) { | |
add703fd | 149 | percpu_ref_reinit(&q->mq_usage_counter); |
320ae51f | 150 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 151 | } |
320ae51f | 152 | } |
b4c6a028 | 153 | EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
320ae51f | 154 | |
aed3ea94 JA |
155 | void blk_mq_wake_waiters(struct request_queue *q) |
156 | { | |
157 | struct blk_mq_hw_ctx *hctx; | |
158 | unsigned int i; | |
159 | ||
160 | queue_for_each_hw_ctx(q, hctx, i) | |
161 | if (blk_mq_hw_queue_mapped(hctx)) | |
162 | blk_mq_tag_wakeup_all(hctx->tags, true); | |
3fd5940c KB |
163 | |
164 | /* | |
165 | * If we are called because the queue has now been marked as | |
166 | * dying, we need to ensure that processes currently waiting on | |
167 | * the queue are notified as well. | |
168 | */ | |
169 | wake_up_all(&q->mq_freeze_wq); | |
aed3ea94 JA |
170 | } |
171 | ||
320ae51f JA |
172 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) |
173 | { | |
174 | return blk_mq_has_free_tags(hctx->tags); | |
175 | } | |
176 | EXPORT_SYMBOL(blk_mq_can_queue); | |
177 | ||
94eddfbe JA |
178 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
179 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 180 | { |
94eddfbe JA |
181 | if (blk_queue_io_stat(q)) |
182 | rw_flags |= REQ_IO_STAT; | |
183 | ||
af76e555 CH |
184 | INIT_LIST_HEAD(&rq->queuelist); |
185 | /* csd/requeue_work/fifo_time is initialized before use */ | |
186 | rq->q = q; | |
320ae51f | 187 | rq->mq_ctx = ctx; |
0d2602ca | 188 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
189 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
190 | rq->cpu = -1; | |
af76e555 CH |
191 | INIT_HLIST_NODE(&rq->hash); |
192 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
193 | rq->rq_disk = NULL; |
194 | rq->part = NULL; | |
3ee32372 | 195 | rq->start_time = jiffies; |
af76e555 CH |
196 | #ifdef CONFIG_BLK_CGROUP |
197 | rq->rl = NULL; | |
0fec08b4 | 198 | set_start_time_ns(rq); |
af76e555 CH |
199 | rq->io_start_time_ns = 0; |
200 | #endif | |
201 | rq->nr_phys_segments = 0; | |
202 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
203 | rq->nr_integrity_segments = 0; | |
204 | #endif | |
af76e555 CH |
205 | rq->special = NULL; |
206 | /* tag was already set */ | |
207 | rq->errors = 0; | |
af76e555 | 208 | |
6f4a1626 TB |
209 | rq->cmd = rq->__cmd; |
210 | ||
af76e555 CH |
211 | rq->extra_len = 0; |
212 | rq->sense_len = 0; | |
213 | rq->resid_len = 0; | |
214 | rq->sense = NULL; | |
215 | ||
af76e555 | 216 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
217 | rq->timeout = 0; |
218 | ||
af76e555 CH |
219 | rq->end_io = NULL; |
220 | rq->end_io_data = NULL; | |
221 | rq->next_rq = NULL; | |
222 | ||
320ae51f JA |
223 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
224 | } | |
225 | ||
5dee8577 | 226 | static struct request * |
cb96a42c | 227 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) |
5dee8577 CH |
228 | { |
229 | struct request *rq; | |
230 | unsigned int tag; | |
231 | ||
cb96a42c | 232 | tag = blk_mq_get_tag(data); |
5dee8577 | 233 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 234 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 235 | |
cb96a42c | 236 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 237 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 238 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
239 | } |
240 | ||
241 | rq->tag = tag; | |
cb96a42c | 242 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); |
5dee8577 CH |
243 | return rq; |
244 | } | |
245 | ||
246 | return NULL; | |
247 | } | |
248 | ||
4ce01dd1 CH |
249 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp, |
250 | bool reserved) | |
320ae51f | 251 | { |
d852564f CH |
252 | struct blk_mq_ctx *ctx; |
253 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 254 | struct request *rq; |
cb96a42c | 255 | struct blk_mq_alloc_data alloc_data; |
a492f075 | 256 | int ret; |
320ae51f | 257 | |
bfd343aa | 258 | ret = blk_mq_queue_enter(q, gfp); |
a492f075 JL |
259 | if (ret) |
260 | return ERR_PTR(ret); | |
320ae51f | 261 | |
d852564f CH |
262 | ctx = blk_mq_get_ctx(q); |
263 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
264 | blk_mq_set_alloc_data(&alloc_data, q, gfp & ~__GFP_WAIT, |
265 | reserved, ctx, hctx); | |
d852564f | 266 | |
cb96a42c | 267 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
d852564f CH |
268 | if (!rq && (gfp & __GFP_WAIT)) { |
269 | __blk_mq_run_hw_queue(hctx); | |
270 | blk_mq_put_ctx(ctx); | |
271 | ||
272 | ctx = blk_mq_get_ctx(q); | |
273 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
274 | blk_mq_set_alloc_data(&alloc_data, q, gfp, reserved, ctx, |
275 | hctx); | |
276 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
277 | ctx = alloc_data.ctx; | |
d852564f CH |
278 | } |
279 | blk_mq_put_ctx(ctx); | |
c76541a9 KB |
280 | if (!rq) { |
281 | blk_mq_queue_exit(q); | |
a492f075 | 282 | return ERR_PTR(-EWOULDBLOCK); |
c76541a9 | 283 | } |
320ae51f JA |
284 | return rq; |
285 | } | |
4bb659b1 | 286 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 287 | |
320ae51f JA |
288 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
289 | struct blk_mq_ctx *ctx, struct request *rq) | |
290 | { | |
291 | const int tag = rq->tag; | |
292 | struct request_queue *q = rq->q; | |
293 | ||
0d2602ca JA |
294 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
295 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 296 | rq->cmd_flags = 0; |
0d2602ca | 297 | |
af76e555 | 298 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 299 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
320ae51f JA |
300 | blk_mq_queue_exit(q); |
301 | } | |
302 | ||
7c7f2f2b | 303 | void blk_mq_free_hctx_request(struct blk_mq_hw_ctx *hctx, struct request *rq) |
320ae51f JA |
304 | { |
305 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
320ae51f JA |
306 | |
307 | ctx->rq_completed[rq_is_sync(rq)]++; | |
320ae51f | 308 | __blk_mq_free_request(hctx, ctx, rq); |
7c7f2f2b JA |
309 | |
310 | } | |
311 | EXPORT_SYMBOL_GPL(blk_mq_free_hctx_request); | |
312 | ||
313 | void blk_mq_free_request(struct request *rq) | |
314 | { | |
315 | struct blk_mq_hw_ctx *hctx; | |
316 | struct request_queue *q = rq->q; | |
317 | ||
318 | hctx = q->mq_ops->map_queue(q, rq->mq_ctx->cpu); | |
319 | blk_mq_free_hctx_request(hctx, rq); | |
320ae51f | 320 | } |
1a3b595a | 321 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 322 | |
c8a446ad | 323 | inline void __blk_mq_end_request(struct request *rq, int error) |
320ae51f | 324 | { |
0d11e6ac ML |
325 | blk_account_io_done(rq); |
326 | ||
91b63639 | 327 | if (rq->end_io) { |
320ae51f | 328 | rq->end_io(rq, error); |
91b63639 CH |
329 | } else { |
330 | if (unlikely(blk_bidi_rq(rq))) | |
331 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 332 | blk_mq_free_request(rq); |
91b63639 | 333 | } |
320ae51f | 334 | } |
c8a446ad | 335 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 336 | |
c8a446ad | 337 | void blk_mq_end_request(struct request *rq, int error) |
63151a44 CH |
338 | { |
339 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
340 | BUG(); | |
c8a446ad | 341 | __blk_mq_end_request(rq, error); |
63151a44 | 342 | } |
c8a446ad | 343 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 344 | |
30a91cb4 | 345 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 346 | { |
3d6efbf6 | 347 | struct request *rq = data; |
320ae51f | 348 | |
30a91cb4 | 349 | rq->q->softirq_done_fn(rq); |
320ae51f | 350 | } |
320ae51f | 351 | |
ed851860 | 352 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
353 | { |
354 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 355 | bool shared = false; |
320ae51f JA |
356 | int cpu; |
357 | ||
38535201 | 358 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
359 | rq->q->softirq_done_fn(rq); |
360 | return; | |
361 | } | |
320ae51f JA |
362 | |
363 | cpu = get_cpu(); | |
38535201 CH |
364 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
365 | shared = cpus_share_cache(cpu, ctx->cpu); | |
366 | ||
367 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 368 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
369 | rq->csd.info = rq; |
370 | rq->csd.flags = 0; | |
c46fff2a | 371 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 372 | } else { |
30a91cb4 | 373 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 374 | } |
320ae51f JA |
375 | put_cpu(); |
376 | } | |
30a91cb4 | 377 | |
ed851860 JA |
378 | void __blk_mq_complete_request(struct request *rq) |
379 | { | |
380 | struct request_queue *q = rq->q; | |
381 | ||
382 | if (!q->softirq_done_fn) | |
c8a446ad | 383 | blk_mq_end_request(rq, rq->errors); |
ed851860 JA |
384 | else |
385 | blk_mq_ipi_complete_request(rq); | |
386 | } | |
387 | ||
30a91cb4 CH |
388 | /** |
389 | * blk_mq_complete_request - end I/O on a request | |
390 | * @rq: the request being processed | |
391 | * | |
392 | * Description: | |
393 | * Ends all I/O on a request. It does not handle partial completions. | |
394 | * The actual completion happens out-of-order, through a IPI handler. | |
395 | **/ | |
f4829a9b | 396 | void blk_mq_complete_request(struct request *rq, int error) |
30a91cb4 | 397 | { |
95f09684 JA |
398 | struct request_queue *q = rq->q; |
399 | ||
400 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 401 | return; |
f4829a9b CH |
402 | if (!blk_mark_rq_complete(rq)) { |
403 | rq->errors = error; | |
ed851860 | 404 | __blk_mq_complete_request(rq); |
f4829a9b | 405 | } |
30a91cb4 CH |
406 | } |
407 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 408 | |
973c0191 KB |
409 | int blk_mq_request_started(struct request *rq) |
410 | { | |
411 | return test_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
412 | } | |
413 | EXPORT_SYMBOL_GPL(blk_mq_request_started); | |
414 | ||
e2490073 | 415 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
416 | { |
417 | struct request_queue *q = rq->q; | |
418 | ||
419 | trace_block_rq_issue(q, rq); | |
420 | ||
742ee69b | 421 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
422 | if (unlikely(blk_bidi_rq(rq))) |
423 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 424 | |
2b8393b4 | 425 | blk_add_timer(rq); |
87ee7b11 | 426 | |
538b7534 JA |
427 | /* |
428 | * Ensure that ->deadline is visible before set the started | |
429 | * flag and clear the completed flag. | |
430 | */ | |
431 | smp_mb__before_atomic(); | |
432 | ||
87ee7b11 JA |
433 | /* |
434 | * Mark us as started and clear complete. Complete might have been | |
435 | * set if requeue raced with timeout, which then marked it as | |
436 | * complete. So be sure to clear complete again when we start | |
437 | * the request, otherwise we'll ignore the completion event. | |
438 | */ | |
4b570521 JA |
439 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
440 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
441 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
442 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
443 | |
444 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
445 | /* | |
446 | * Make sure space for the drain appears. We know we can do | |
447 | * this because max_hw_segments has been adjusted to be one | |
448 | * fewer than the device can handle. | |
449 | */ | |
450 | rq->nr_phys_segments++; | |
451 | } | |
320ae51f | 452 | } |
e2490073 | 453 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 454 | |
ed0791b2 | 455 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
456 | { |
457 | struct request_queue *q = rq->q; | |
458 | ||
459 | trace_block_rq_requeue(q, rq); | |
49f5baa5 | 460 | |
e2490073 CH |
461 | if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
462 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
463 | rq->nr_phys_segments--; | |
464 | } | |
320ae51f JA |
465 | } |
466 | ||
ed0791b2 CH |
467 | void blk_mq_requeue_request(struct request *rq) |
468 | { | |
ed0791b2 | 469 | __blk_mq_requeue_request(rq); |
ed0791b2 | 470 | |
ed0791b2 | 471 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 472 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
473 | } |
474 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
475 | ||
6fca6a61 CH |
476 | static void blk_mq_requeue_work(struct work_struct *work) |
477 | { | |
478 | struct request_queue *q = | |
479 | container_of(work, struct request_queue, requeue_work); | |
480 | LIST_HEAD(rq_list); | |
481 | struct request *rq, *next; | |
482 | unsigned long flags; | |
483 | ||
484 | spin_lock_irqsave(&q->requeue_lock, flags); | |
485 | list_splice_init(&q->requeue_list, &rq_list); | |
486 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
487 | ||
488 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
489 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
490 | continue; | |
491 | ||
492 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
493 | list_del_init(&rq->queuelist); | |
494 | blk_mq_insert_request(rq, true, false, false); | |
495 | } | |
496 | ||
497 | while (!list_empty(&rq_list)) { | |
498 | rq = list_entry(rq_list.next, struct request, queuelist); | |
499 | list_del_init(&rq->queuelist); | |
500 | blk_mq_insert_request(rq, false, false, false); | |
501 | } | |
502 | ||
8b957415 JA |
503 | /* |
504 | * Use the start variant of queue running here, so that running | |
505 | * the requeue work will kick stopped queues. | |
506 | */ | |
507 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
508 | } |
509 | ||
510 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
511 | { | |
512 | struct request_queue *q = rq->q; | |
513 | unsigned long flags; | |
514 | ||
515 | /* | |
516 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
517 | * request head insertation from the workqueue. | |
518 | */ | |
519 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
520 | ||
521 | spin_lock_irqsave(&q->requeue_lock, flags); | |
522 | if (at_head) { | |
523 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
524 | list_add(&rq->queuelist, &q->requeue_list); | |
525 | } else { | |
526 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
527 | } | |
528 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
529 | } | |
530 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
531 | ||
c68ed59f KB |
532 | void blk_mq_cancel_requeue_work(struct request_queue *q) |
533 | { | |
534 | cancel_work_sync(&q->requeue_work); | |
535 | } | |
536 | EXPORT_SYMBOL_GPL(blk_mq_cancel_requeue_work); | |
537 | ||
6fca6a61 CH |
538 | void blk_mq_kick_requeue_list(struct request_queue *q) |
539 | { | |
540 | kblockd_schedule_work(&q->requeue_work); | |
541 | } | |
542 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
543 | ||
1885b24d JA |
544 | void blk_mq_abort_requeue_list(struct request_queue *q) |
545 | { | |
546 | unsigned long flags; | |
547 | LIST_HEAD(rq_list); | |
548 | ||
549 | spin_lock_irqsave(&q->requeue_lock, flags); | |
550 | list_splice_init(&q->requeue_list, &rq_list); | |
551 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
552 | ||
553 | while (!list_empty(&rq_list)) { | |
554 | struct request *rq; | |
555 | ||
556 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
557 | list_del_init(&rq->queuelist); | |
558 | rq->errors = -EIO; | |
559 | blk_mq_end_request(rq, rq->errors); | |
560 | } | |
561 | } | |
562 | EXPORT_SYMBOL(blk_mq_abort_requeue_list); | |
563 | ||
0e62f51f JA |
564 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) |
565 | { | |
0048b483 | 566 | return tags->rqs[tag]; |
24d2f903 CH |
567 | } |
568 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
569 | ||
320ae51f | 570 | struct blk_mq_timeout_data { |
46f92d42 CH |
571 | unsigned long next; |
572 | unsigned int next_set; | |
320ae51f JA |
573 | }; |
574 | ||
90415837 | 575 | void blk_mq_rq_timed_out(struct request *req, bool reserved) |
320ae51f | 576 | { |
46f92d42 CH |
577 | struct blk_mq_ops *ops = req->q->mq_ops; |
578 | enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER; | |
87ee7b11 JA |
579 | |
580 | /* | |
581 | * We know that complete is set at this point. If STARTED isn't set | |
582 | * anymore, then the request isn't active and the "timeout" should | |
583 | * just be ignored. This can happen due to the bitflag ordering. | |
584 | * Timeout first checks if STARTED is set, and if it is, assumes | |
585 | * the request is active. But if we race with completion, then | |
586 | * we both flags will get cleared. So check here again, and ignore | |
587 | * a timeout event with a request that isn't active. | |
588 | */ | |
46f92d42 CH |
589 | if (!test_bit(REQ_ATOM_STARTED, &req->atomic_flags)) |
590 | return; | |
87ee7b11 | 591 | |
46f92d42 | 592 | if (ops->timeout) |
0152fb6b | 593 | ret = ops->timeout(req, reserved); |
46f92d42 CH |
594 | |
595 | switch (ret) { | |
596 | case BLK_EH_HANDLED: | |
597 | __blk_mq_complete_request(req); | |
598 | break; | |
599 | case BLK_EH_RESET_TIMER: | |
600 | blk_add_timer(req); | |
601 | blk_clear_rq_complete(req); | |
602 | break; | |
603 | case BLK_EH_NOT_HANDLED: | |
604 | break; | |
605 | default: | |
606 | printk(KERN_ERR "block: bad eh return: %d\n", ret); | |
607 | break; | |
608 | } | |
87ee7b11 | 609 | } |
5b3f25fc | 610 | |
81481eb4 CH |
611 | static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, |
612 | struct request *rq, void *priv, bool reserved) | |
613 | { | |
614 | struct blk_mq_timeout_data *data = priv; | |
87ee7b11 | 615 | |
eb130dbf KB |
616 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
617 | /* | |
618 | * If a request wasn't started before the queue was | |
619 | * marked dying, kill it here or it'll go unnoticed. | |
620 | */ | |
f4829a9b CH |
621 | if (unlikely(blk_queue_dying(rq->q))) |
622 | blk_mq_complete_request(rq, -EIO); | |
46f92d42 | 623 | return; |
eb130dbf | 624 | } |
5b3f25fc KB |
625 | if (rq->cmd_flags & REQ_NO_TIMEOUT) |
626 | return; | |
87ee7b11 | 627 | |
46f92d42 CH |
628 | if (time_after_eq(jiffies, rq->deadline)) { |
629 | if (!blk_mark_rq_complete(rq)) | |
0152fb6b | 630 | blk_mq_rq_timed_out(rq, reserved); |
46f92d42 CH |
631 | } else if (!data->next_set || time_after(data->next, rq->deadline)) { |
632 | data->next = rq->deadline; | |
633 | data->next_set = 1; | |
634 | } | |
87ee7b11 JA |
635 | } |
636 | ||
81481eb4 | 637 | static void blk_mq_rq_timer(unsigned long priv) |
320ae51f | 638 | { |
81481eb4 CH |
639 | struct request_queue *q = (struct request_queue *)priv; |
640 | struct blk_mq_timeout_data data = { | |
641 | .next = 0, | |
642 | .next_set = 0, | |
643 | }; | |
81481eb4 | 644 | int i; |
320ae51f | 645 | |
0bf6cd5b | 646 | blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &data); |
320ae51f | 647 | |
81481eb4 CH |
648 | if (data.next_set) { |
649 | data.next = blk_rq_timeout(round_jiffies_up(data.next)); | |
650 | mod_timer(&q->timeout, data.next); | |
0d2602ca | 651 | } else { |
0bf6cd5b CH |
652 | struct blk_mq_hw_ctx *hctx; |
653 | ||
f054b56c ML |
654 | queue_for_each_hw_ctx(q, hctx, i) { |
655 | /* the hctx may be unmapped, so check it here */ | |
656 | if (blk_mq_hw_queue_mapped(hctx)) | |
657 | blk_mq_tag_idle(hctx); | |
658 | } | |
0d2602ca | 659 | } |
320ae51f JA |
660 | } |
661 | ||
662 | /* | |
663 | * Reverse check our software queue for entries that we could potentially | |
664 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
665 | * too much time checking for merges. | |
666 | */ | |
667 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
668 | struct blk_mq_ctx *ctx, struct bio *bio) | |
669 | { | |
670 | struct request *rq; | |
671 | int checked = 8; | |
672 | ||
673 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
674 | int el_ret; | |
675 | ||
676 | if (!checked--) | |
677 | break; | |
678 | ||
679 | if (!blk_rq_merge_ok(rq, bio)) | |
680 | continue; | |
681 | ||
682 | el_ret = blk_try_merge(rq, bio); | |
683 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
684 | if (bio_attempt_back_merge(q, rq, bio)) { | |
685 | ctx->rq_merged++; | |
686 | return true; | |
687 | } | |
688 | break; | |
689 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
690 | if (bio_attempt_front_merge(q, rq, bio)) { | |
691 | ctx->rq_merged++; | |
692 | return true; | |
693 | } | |
694 | break; | |
695 | } | |
696 | } | |
697 | ||
698 | return false; | |
699 | } | |
700 | ||
1429d7c9 JA |
701 | /* |
702 | * Process software queues that have been marked busy, splicing them | |
703 | * to the for-dispatch | |
704 | */ | |
705 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
706 | { | |
707 | struct blk_mq_ctx *ctx; | |
708 | int i; | |
709 | ||
569fd0ce | 710 | for (i = 0; i < hctx->ctx_map.size; i++) { |
1429d7c9 JA |
711 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; |
712 | unsigned int off, bit; | |
713 | ||
714 | if (!bm->word) | |
715 | continue; | |
716 | ||
717 | bit = 0; | |
718 | off = i * hctx->ctx_map.bits_per_word; | |
719 | do { | |
720 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
721 | if (bit >= bm->depth) | |
722 | break; | |
723 | ||
724 | ctx = hctx->ctxs[bit + off]; | |
725 | clear_bit(bit, &bm->word); | |
726 | spin_lock(&ctx->lock); | |
727 | list_splice_tail_init(&ctx->rq_list, list); | |
728 | spin_unlock(&ctx->lock); | |
729 | ||
730 | bit++; | |
731 | } while (1); | |
732 | } | |
733 | } | |
734 | ||
320ae51f JA |
735 | /* |
736 | * Run this hardware queue, pulling any software queues mapped to it in. | |
737 | * Note that this function currently has various problems around ordering | |
738 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
739 | * items on the hctx->dispatch list. Ignore that for now. | |
740 | */ | |
741 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
742 | { | |
743 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
744 | struct request *rq; |
745 | LIST_HEAD(rq_list); | |
74c45052 JA |
746 | LIST_HEAD(driver_list); |
747 | struct list_head *dptr; | |
1429d7c9 | 748 | int queued; |
320ae51f | 749 | |
fd1270d5 | 750 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 751 | |
5d12f905 | 752 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
753 | return; |
754 | ||
755 | hctx->run++; | |
756 | ||
757 | /* | |
758 | * Touch any software queue that has pending entries. | |
759 | */ | |
1429d7c9 | 760 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
761 | |
762 | /* | |
763 | * If we have previous entries on our dispatch list, grab them | |
764 | * and stuff them at the front for more fair dispatch. | |
765 | */ | |
766 | if (!list_empty_careful(&hctx->dispatch)) { | |
767 | spin_lock(&hctx->lock); | |
768 | if (!list_empty(&hctx->dispatch)) | |
769 | list_splice_init(&hctx->dispatch, &rq_list); | |
770 | spin_unlock(&hctx->lock); | |
771 | } | |
772 | ||
74c45052 JA |
773 | /* |
774 | * Start off with dptr being NULL, so we start the first request | |
775 | * immediately, even if we have more pending. | |
776 | */ | |
777 | dptr = NULL; | |
778 | ||
320ae51f JA |
779 | /* |
780 | * Now process all the entries, sending them to the driver. | |
781 | */ | |
1429d7c9 | 782 | queued = 0; |
320ae51f | 783 | while (!list_empty(&rq_list)) { |
74c45052 | 784 | struct blk_mq_queue_data bd; |
320ae51f JA |
785 | int ret; |
786 | ||
787 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
788 | list_del_init(&rq->queuelist); | |
320ae51f | 789 | |
74c45052 JA |
790 | bd.rq = rq; |
791 | bd.list = dptr; | |
792 | bd.last = list_empty(&rq_list); | |
793 | ||
794 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
320ae51f JA |
795 | switch (ret) { |
796 | case BLK_MQ_RQ_QUEUE_OK: | |
797 | queued++; | |
798 | continue; | |
799 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 800 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 801 | __blk_mq_requeue_request(rq); |
320ae51f JA |
802 | break; |
803 | default: | |
804 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 805 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 806 | rq->errors = -EIO; |
c8a446ad | 807 | blk_mq_end_request(rq, rq->errors); |
320ae51f JA |
808 | break; |
809 | } | |
810 | ||
811 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
812 | break; | |
74c45052 JA |
813 | |
814 | /* | |
815 | * We've done the first request. If we have more than 1 | |
816 | * left in the list, set dptr to defer issue. | |
817 | */ | |
818 | if (!dptr && rq_list.next != rq_list.prev) | |
819 | dptr = &driver_list; | |
320ae51f JA |
820 | } |
821 | ||
822 | if (!queued) | |
823 | hctx->dispatched[0]++; | |
824 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
825 | hctx->dispatched[ilog2(queued) + 1]++; | |
826 | ||
827 | /* | |
828 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
829 | * that is where we will continue on next queue run. | |
830 | */ | |
831 | if (!list_empty(&rq_list)) { | |
832 | spin_lock(&hctx->lock); | |
833 | list_splice(&rq_list, &hctx->dispatch); | |
834 | spin_unlock(&hctx->lock); | |
9ba52e58 SL |
835 | /* |
836 | * the queue is expected stopped with BLK_MQ_RQ_QUEUE_BUSY, but | |
837 | * it's possible the queue is stopped and restarted again | |
838 | * before this. Queue restart will dispatch requests. And since | |
839 | * requests in rq_list aren't added into hctx->dispatch yet, | |
840 | * the requests in rq_list might get lost. | |
841 | * | |
842 | * blk_mq_run_hw_queue() already checks the STOPPED bit | |
843 | **/ | |
844 | blk_mq_run_hw_queue(hctx, true); | |
320ae51f JA |
845 | } |
846 | } | |
847 | ||
506e931f JA |
848 | /* |
849 | * It'd be great if the workqueue API had a way to pass | |
850 | * in a mask and had some smarts for more clever placement. | |
851 | * For now we just round-robin here, switching for every | |
852 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
853 | */ | |
854 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
855 | { | |
b657d7e6 CH |
856 | if (hctx->queue->nr_hw_queues == 1) |
857 | return WORK_CPU_UNBOUND; | |
506e931f JA |
858 | |
859 | if (--hctx->next_cpu_batch <= 0) { | |
b657d7e6 | 860 | int cpu = hctx->next_cpu, next_cpu; |
506e931f JA |
861 | |
862 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
863 | if (next_cpu >= nr_cpu_ids) | |
864 | next_cpu = cpumask_first(hctx->cpumask); | |
865 | ||
866 | hctx->next_cpu = next_cpu; | |
867 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
b657d7e6 CH |
868 | |
869 | return cpu; | |
506e931f JA |
870 | } |
871 | ||
b657d7e6 | 872 | return hctx->next_cpu; |
506e931f JA |
873 | } |
874 | ||
320ae51f JA |
875 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
876 | { | |
19c66e59 ML |
877 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state) || |
878 | !blk_mq_hw_queue_mapped(hctx))) | |
320ae51f JA |
879 | return; |
880 | ||
398205b8 | 881 | if (!async) { |
2a90d4aa PB |
882 | int cpu = get_cpu(); |
883 | if (cpumask_test_cpu(cpu, hctx->cpumask)) { | |
398205b8 | 884 | __blk_mq_run_hw_queue(hctx); |
2a90d4aa | 885 | put_cpu(); |
398205b8 PB |
886 | return; |
887 | } | |
e4043dcf | 888 | |
2a90d4aa | 889 | put_cpu(); |
e4043dcf | 890 | } |
398205b8 | 891 | |
b657d7e6 CH |
892 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
893 | &hctx->run_work, 0); | |
320ae51f JA |
894 | } |
895 | ||
b94ec296 | 896 | void blk_mq_run_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
897 | { |
898 | struct blk_mq_hw_ctx *hctx; | |
899 | int i; | |
900 | ||
901 | queue_for_each_hw_ctx(q, hctx, i) { | |
902 | if ((!blk_mq_hctx_has_pending(hctx) && | |
903 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 904 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
905 | continue; |
906 | ||
b94ec296 | 907 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
908 | } |
909 | } | |
b94ec296 | 910 | EXPORT_SYMBOL(blk_mq_run_hw_queues); |
320ae51f JA |
911 | |
912 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
913 | { | |
70f4db63 CH |
914 | cancel_delayed_work(&hctx->run_work); |
915 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
916 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
917 | } | |
918 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
919 | ||
280d45f6 CH |
920 | void blk_mq_stop_hw_queues(struct request_queue *q) |
921 | { | |
922 | struct blk_mq_hw_ctx *hctx; | |
923 | int i; | |
924 | ||
925 | queue_for_each_hw_ctx(q, hctx, i) | |
926 | blk_mq_stop_hw_queue(hctx); | |
927 | } | |
928 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
929 | ||
320ae51f JA |
930 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
931 | { | |
932 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 933 | |
0ffbce80 | 934 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
935 | } |
936 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
937 | ||
2f268556 CH |
938 | void blk_mq_start_hw_queues(struct request_queue *q) |
939 | { | |
940 | struct blk_mq_hw_ctx *hctx; | |
941 | int i; | |
942 | ||
943 | queue_for_each_hw_ctx(q, hctx, i) | |
944 | blk_mq_start_hw_queue(hctx); | |
945 | } | |
946 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
947 | ||
1b4a3258 | 948 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
949 | { |
950 | struct blk_mq_hw_ctx *hctx; | |
951 | int i; | |
952 | ||
953 | queue_for_each_hw_ctx(q, hctx, i) { | |
954 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
955 | continue; | |
956 | ||
957 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
1b4a3258 | 958 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
959 | } |
960 | } | |
961 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
962 | ||
70f4db63 | 963 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
964 | { |
965 | struct blk_mq_hw_ctx *hctx; | |
966 | ||
70f4db63 | 967 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 968 | |
320ae51f JA |
969 | __blk_mq_run_hw_queue(hctx); |
970 | } | |
971 | ||
70f4db63 CH |
972 | static void blk_mq_delay_work_fn(struct work_struct *work) |
973 | { | |
974 | struct blk_mq_hw_ctx *hctx; | |
975 | ||
976 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
977 | ||
978 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
979 | __blk_mq_run_hw_queue(hctx); | |
980 | } | |
981 | ||
982 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
983 | { | |
19c66e59 ML |
984 | if (unlikely(!blk_mq_hw_queue_mapped(hctx))) |
985 | return; | |
70f4db63 | 986 | |
b657d7e6 CH |
987 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
988 | &hctx->delay_work, msecs_to_jiffies(msecs)); | |
70f4db63 CH |
989 | } |
990 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
991 | ||
320ae51f | 992 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
72a0a36e | 993 | struct request *rq, bool at_head) |
320ae51f JA |
994 | { |
995 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
996 | ||
01b983c9 JA |
997 | trace_block_rq_insert(hctx->queue, rq); |
998 | ||
72a0a36e CH |
999 | if (at_head) |
1000 | list_add(&rq->queuelist, &ctx->rq_list); | |
1001 | else | |
1002 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
4bb659b1 | 1003 | |
320ae51f | 1004 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
1005 | } |
1006 | ||
eeabc850 CH |
1007 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
1008 | bool async) | |
320ae51f | 1009 | { |
eeabc850 | 1010 | struct request_queue *q = rq->q; |
320ae51f | 1011 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
1012 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
1013 | ||
1014 | current_ctx = blk_mq_get_ctx(q); | |
1015 | if (!cpu_online(ctx->cpu)) | |
1016 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 1017 | |
320ae51f JA |
1018 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
1019 | ||
a57a178a CH |
1020 | spin_lock(&ctx->lock); |
1021 | __blk_mq_insert_request(hctx, rq, at_head); | |
1022 | spin_unlock(&ctx->lock); | |
320ae51f | 1023 | |
320ae51f JA |
1024 | if (run_queue) |
1025 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
1026 | |
1027 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
1028 | } |
1029 | ||
1030 | static void blk_mq_insert_requests(struct request_queue *q, | |
1031 | struct blk_mq_ctx *ctx, | |
1032 | struct list_head *list, | |
1033 | int depth, | |
1034 | bool from_schedule) | |
1035 | ||
1036 | { | |
1037 | struct blk_mq_hw_ctx *hctx; | |
1038 | struct blk_mq_ctx *current_ctx; | |
1039 | ||
1040 | trace_block_unplug(q, depth, !from_schedule); | |
1041 | ||
1042 | current_ctx = blk_mq_get_ctx(q); | |
1043 | ||
1044 | if (!cpu_online(ctx->cpu)) | |
1045 | ctx = current_ctx; | |
1046 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1047 | ||
1048 | /* | |
1049 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
1050 | * offline now | |
1051 | */ | |
1052 | spin_lock(&ctx->lock); | |
1053 | while (!list_empty(list)) { | |
1054 | struct request *rq; | |
1055 | ||
1056 | rq = list_first_entry(list, struct request, queuelist); | |
1057 | list_del_init(&rq->queuelist); | |
1058 | rq->mq_ctx = ctx; | |
72a0a36e | 1059 | __blk_mq_insert_request(hctx, rq, false); |
320ae51f JA |
1060 | } |
1061 | spin_unlock(&ctx->lock); | |
1062 | ||
320ae51f | 1063 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 1064 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
1065 | } |
1066 | ||
1067 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1068 | { | |
1069 | struct request *rqa = container_of(a, struct request, queuelist); | |
1070 | struct request *rqb = container_of(b, struct request, queuelist); | |
1071 | ||
1072 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1073 | (rqa->mq_ctx == rqb->mq_ctx && | |
1074 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1075 | } | |
1076 | ||
1077 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1078 | { | |
1079 | struct blk_mq_ctx *this_ctx; | |
1080 | struct request_queue *this_q; | |
1081 | struct request *rq; | |
1082 | LIST_HEAD(list); | |
1083 | LIST_HEAD(ctx_list); | |
1084 | unsigned int depth; | |
1085 | ||
1086 | list_splice_init(&plug->mq_list, &list); | |
1087 | ||
1088 | list_sort(NULL, &list, plug_ctx_cmp); | |
1089 | ||
1090 | this_q = NULL; | |
1091 | this_ctx = NULL; | |
1092 | depth = 0; | |
1093 | ||
1094 | while (!list_empty(&list)) { | |
1095 | rq = list_entry_rq(list.next); | |
1096 | list_del_init(&rq->queuelist); | |
1097 | BUG_ON(!rq->q); | |
1098 | if (rq->mq_ctx != this_ctx) { | |
1099 | if (this_ctx) { | |
1100 | blk_mq_insert_requests(this_q, this_ctx, | |
1101 | &ctx_list, depth, | |
1102 | from_schedule); | |
1103 | } | |
1104 | ||
1105 | this_ctx = rq->mq_ctx; | |
1106 | this_q = rq->q; | |
1107 | depth = 0; | |
1108 | } | |
1109 | ||
1110 | depth++; | |
1111 | list_add_tail(&rq->queuelist, &ctx_list); | |
1112 | } | |
1113 | ||
1114 | /* | |
1115 | * If 'this_ctx' is set, we know we have entries to complete | |
1116 | * on 'ctx_list'. Do those. | |
1117 | */ | |
1118 | if (this_ctx) { | |
1119 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1120 | from_schedule); | |
1121 | } | |
1122 | } | |
1123 | ||
1124 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1125 | { | |
1126 | init_request_from_bio(rq, bio); | |
4b570521 | 1127 | |
3ee32372 | 1128 | if (blk_do_io_stat(rq)) |
4b570521 | 1129 | blk_account_io_start(rq, 1); |
320ae51f JA |
1130 | } |
1131 | ||
274a5843 JA |
1132 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1133 | { | |
1134 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1135 | !blk_queue_nomerges(hctx->queue); | |
1136 | } | |
1137 | ||
07068d5b JA |
1138 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1139 | struct blk_mq_ctx *ctx, | |
1140 | struct request *rq, struct bio *bio) | |
320ae51f | 1141 | { |
274a5843 | 1142 | if (!hctx_allow_merges(hctx)) { |
07068d5b JA |
1143 | blk_mq_bio_to_request(rq, bio); |
1144 | spin_lock(&ctx->lock); | |
1145 | insert_rq: | |
1146 | __blk_mq_insert_request(hctx, rq, false); | |
1147 | spin_unlock(&ctx->lock); | |
1148 | return false; | |
1149 | } else { | |
274a5843 JA |
1150 | struct request_queue *q = hctx->queue; |
1151 | ||
07068d5b JA |
1152 | spin_lock(&ctx->lock); |
1153 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1154 | blk_mq_bio_to_request(rq, bio); | |
1155 | goto insert_rq; | |
1156 | } | |
320ae51f | 1157 | |
07068d5b JA |
1158 | spin_unlock(&ctx->lock); |
1159 | __blk_mq_free_request(hctx, ctx, rq); | |
1160 | return true; | |
14ec77f3 | 1161 | } |
07068d5b | 1162 | } |
14ec77f3 | 1163 | |
07068d5b JA |
1164 | struct blk_map_ctx { |
1165 | struct blk_mq_hw_ctx *hctx; | |
1166 | struct blk_mq_ctx *ctx; | |
1167 | }; | |
1168 | ||
1169 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1170 | struct bio *bio, | |
1171 | struct blk_map_ctx *data) | |
1172 | { | |
1173 | struct blk_mq_hw_ctx *hctx; | |
1174 | struct blk_mq_ctx *ctx; | |
1175 | struct request *rq; | |
1176 | int rw = bio_data_dir(bio); | |
cb96a42c | 1177 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1178 | |
bfd343aa | 1179 | if (unlikely(blk_mq_queue_enter(q, GFP_KERNEL))) { |
4246a0b6 | 1180 | bio_io_error(bio); |
07068d5b | 1181 | return NULL; |
320ae51f JA |
1182 | } |
1183 | ||
1184 | ctx = blk_mq_get_ctx(q); | |
1185 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1186 | ||
07068d5b | 1187 | if (rw_is_sync(bio->bi_rw)) |
27fbf4e8 | 1188 | rw |= REQ_SYNC; |
07068d5b | 1189 | |
320ae51f | 1190 | trace_block_getrq(q, bio, rw); |
cb96a42c ML |
1191 | blk_mq_set_alloc_data(&alloc_data, q, GFP_ATOMIC, false, ctx, |
1192 | hctx); | |
1193 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
5dee8577 | 1194 | if (unlikely(!rq)) { |
793597a6 | 1195 | __blk_mq_run_hw_queue(hctx); |
320ae51f JA |
1196 | blk_mq_put_ctx(ctx); |
1197 | trace_block_sleeprq(q, bio, rw); | |
793597a6 CH |
1198 | |
1199 | ctx = blk_mq_get_ctx(q); | |
320ae51f | 1200 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
cb96a42c ML |
1201 | blk_mq_set_alloc_data(&alloc_data, q, |
1202 | __GFP_WAIT|GFP_ATOMIC, false, ctx, hctx); | |
1203 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
1204 | ctx = alloc_data.ctx; | |
1205 | hctx = alloc_data.hctx; | |
320ae51f JA |
1206 | } |
1207 | ||
1208 | hctx->queued++; | |
07068d5b JA |
1209 | data->hctx = hctx; |
1210 | data->ctx = ctx; | |
1211 | return rq; | |
1212 | } | |
1213 | ||
f984df1f SL |
1214 | static int blk_mq_direct_issue_request(struct request *rq) |
1215 | { | |
1216 | int ret; | |
1217 | struct request_queue *q = rq->q; | |
1218 | struct blk_mq_hw_ctx *hctx = q->mq_ops->map_queue(q, | |
1219 | rq->mq_ctx->cpu); | |
1220 | struct blk_mq_queue_data bd = { | |
1221 | .rq = rq, | |
1222 | .list = NULL, | |
1223 | .last = 1 | |
1224 | }; | |
1225 | ||
1226 | /* | |
1227 | * For OK queue, we are done. For error, kill it. Any other | |
1228 | * error (busy), just add it to our list as we previously | |
1229 | * would have done | |
1230 | */ | |
1231 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
1232 | if (ret == BLK_MQ_RQ_QUEUE_OK) | |
1233 | return 0; | |
1234 | else { | |
1235 | __blk_mq_requeue_request(rq); | |
1236 | ||
1237 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1238 | rq->errors = -EIO; | |
1239 | blk_mq_end_request(rq, rq->errors); | |
1240 | return 0; | |
1241 | } | |
1242 | return -1; | |
1243 | } | |
1244 | } | |
1245 | ||
07068d5b JA |
1246 | /* |
1247 | * Multiple hardware queue variant. This will not use per-process plugs, | |
1248 | * but will attempt to bypass the hctx queueing if we can go straight to | |
1249 | * hardware for SYNC IO. | |
1250 | */ | |
1251 | static void blk_mq_make_request(struct request_queue *q, struct bio *bio) | |
1252 | { | |
1253 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1254 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1255 | struct blk_map_ctx data; | |
1256 | struct request *rq; | |
f984df1f SL |
1257 | unsigned int request_count = 0; |
1258 | struct blk_plug *plug; | |
5b3f341f | 1259 | struct request *same_queue_rq = NULL; |
07068d5b JA |
1260 | |
1261 | blk_queue_bounce(q, &bio); | |
1262 | ||
1263 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1264 | bio_io_error(bio); |
07068d5b JA |
1265 | return; |
1266 | } | |
1267 | ||
54efd50b KO |
1268 | blk_queue_split(q, &bio, q->bio_split); |
1269 | ||
f984df1f | 1270 | if (!is_flush_fua && !blk_queue_nomerges(q) && |
5b3f341f | 1271 | blk_attempt_plug_merge(q, bio, &request_count, &same_queue_rq)) |
f984df1f SL |
1272 | return; |
1273 | ||
07068d5b JA |
1274 | rq = blk_mq_map_request(q, bio, &data); |
1275 | if (unlikely(!rq)) | |
1276 | return; | |
1277 | ||
1278 | if (unlikely(is_flush_fua)) { | |
1279 | blk_mq_bio_to_request(rq, bio); | |
1280 | blk_insert_flush(rq); | |
1281 | goto run_queue; | |
1282 | } | |
1283 | ||
f984df1f | 1284 | plug = current->plug; |
e167dfb5 JA |
1285 | /* |
1286 | * If the driver supports defer issued based on 'last', then | |
1287 | * queue it up like normal since we can potentially save some | |
1288 | * CPU this way. | |
1289 | */ | |
f984df1f SL |
1290 | if (((plug && !blk_queue_nomerges(q)) || is_sync) && |
1291 | !(data.hctx->flags & BLK_MQ_F_DEFER_ISSUE)) { | |
1292 | struct request *old_rq = NULL; | |
07068d5b JA |
1293 | |
1294 | blk_mq_bio_to_request(rq, bio); | |
07068d5b JA |
1295 | |
1296 | /* | |
f984df1f SL |
1297 | * we do limited pluging. If bio can be merged, do merge. |
1298 | * Otherwise the existing request in the plug list will be | |
1299 | * issued. So the plug list will have one request at most | |
07068d5b | 1300 | */ |
f984df1f | 1301 | if (plug) { |
5b3f341f SL |
1302 | /* |
1303 | * The plug list might get flushed before this. If that | |
1304 | * happens, same_queue_rq is invalid and plug list is empty | |
1305 | **/ | |
1306 | if (same_queue_rq && !list_empty(&plug->mq_list)) { | |
1307 | old_rq = same_queue_rq; | |
f984df1f | 1308 | list_del_init(&old_rq->queuelist); |
07068d5b | 1309 | } |
f984df1f SL |
1310 | list_add_tail(&rq->queuelist, &plug->mq_list); |
1311 | } else /* is_sync */ | |
1312 | old_rq = rq; | |
1313 | blk_mq_put_ctx(data.ctx); | |
1314 | if (!old_rq) | |
239ad215 | 1315 | return; |
f984df1f SL |
1316 | if (!blk_mq_direct_issue_request(old_rq)) |
1317 | return; | |
1318 | blk_mq_insert_request(old_rq, false, true, true); | |
1319 | return; | |
07068d5b JA |
1320 | } |
1321 | ||
1322 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { | |
1323 | /* | |
1324 | * For a SYNC request, send it to the hardware immediately. For | |
1325 | * an ASYNC request, just ensure that we run it later on. The | |
1326 | * latter allows for merging opportunities and more efficient | |
1327 | * dispatching. | |
1328 | */ | |
1329 | run_queue: | |
1330 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
1331 | } | |
07068d5b JA |
1332 | blk_mq_put_ctx(data.ctx); |
1333 | } | |
1334 | ||
1335 | /* | |
1336 | * Single hardware queue variant. This will attempt to use any per-process | |
1337 | * plug for merging and IO deferral. | |
1338 | */ | |
1339 | static void blk_sq_make_request(struct request_queue *q, struct bio *bio) | |
1340 | { | |
1341 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1342 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
e6c4438b JM |
1343 | struct blk_plug *plug; |
1344 | unsigned int request_count = 0; | |
07068d5b JA |
1345 | struct blk_map_ctx data; |
1346 | struct request *rq; | |
1347 | ||
07068d5b JA |
1348 | blk_queue_bounce(q, &bio); |
1349 | ||
1350 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
4246a0b6 | 1351 | bio_io_error(bio); |
07068d5b JA |
1352 | return; |
1353 | } | |
1354 | ||
54efd50b KO |
1355 | blk_queue_split(q, &bio, q->bio_split); |
1356 | ||
e6c4438b | 1357 | if (!is_flush_fua && !blk_queue_nomerges(q) && |
5b3f341f | 1358 | blk_attempt_plug_merge(q, bio, &request_count, NULL)) |
07068d5b JA |
1359 | return; |
1360 | ||
1361 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec JA |
1362 | if (unlikely(!rq)) |
1363 | return; | |
320ae51f JA |
1364 | |
1365 | if (unlikely(is_flush_fua)) { | |
1366 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1367 | blk_insert_flush(rq); |
1368 | goto run_queue; | |
1369 | } | |
1370 | ||
1371 | /* | |
1372 | * A task plug currently exists. Since this is completely lockless, | |
1373 | * utilize that to temporarily store requests until the task is | |
1374 | * either done or scheduled away. | |
1375 | */ | |
e6c4438b JM |
1376 | plug = current->plug; |
1377 | if (plug) { | |
1378 | blk_mq_bio_to_request(rq, bio); | |
1379 | if (list_empty(&plug->mq_list)) | |
1380 | trace_block_plug(q); | |
1381 | else if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
1382 | blk_flush_plug_list(plug, false); | |
1383 | trace_block_plug(q); | |
320ae51f | 1384 | } |
e6c4438b JM |
1385 | list_add_tail(&rq->queuelist, &plug->mq_list); |
1386 | blk_mq_put_ctx(data.ctx); | |
1387 | return; | |
320ae51f JA |
1388 | } |
1389 | ||
07068d5b JA |
1390 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1391 | /* | |
1392 | * For a SYNC request, send it to the hardware immediately. For | |
1393 | * an ASYNC request, just ensure that we run it later on. The | |
1394 | * latter allows for merging opportunities and more efficient | |
1395 | * dispatching. | |
1396 | */ | |
1397 | run_queue: | |
1398 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1399 | } |
1400 | ||
07068d5b | 1401 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1402 | } |
1403 | ||
1404 | /* | |
1405 | * Default mapping to a software queue, since we use one per CPU. | |
1406 | */ | |
1407 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1408 | { | |
1409 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1410 | } | |
1411 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1412 | ||
24d2f903 CH |
1413 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1414 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1415 | { |
e9b267d9 | 1416 | struct page *page; |
320ae51f | 1417 | |
24d2f903 | 1418 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1419 | int i; |
320ae51f | 1420 | |
24d2f903 CH |
1421 | for (i = 0; i < tags->nr_tags; i++) { |
1422 | if (!tags->rqs[i]) | |
e9b267d9 | 1423 | continue; |
24d2f903 CH |
1424 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1425 | hctx_idx, i); | |
a5164405 | 1426 | tags->rqs[i] = NULL; |
e9b267d9 | 1427 | } |
320ae51f | 1428 | } |
320ae51f | 1429 | |
24d2f903 CH |
1430 | while (!list_empty(&tags->page_list)) { |
1431 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1432 | list_del_init(&page->lru); |
320ae51f JA |
1433 | __free_pages(page, page->private); |
1434 | } | |
1435 | ||
24d2f903 | 1436 | kfree(tags->rqs); |
320ae51f | 1437 | |
24d2f903 | 1438 | blk_mq_free_tags(tags); |
320ae51f JA |
1439 | } |
1440 | ||
1441 | static size_t order_to_size(unsigned int order) | |
1442 | { | |
4ca08500 | 1443 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1444 | } |
1445 | ||
24d2f903 CH |
1446 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1447 | unsigned int hctx_idx) | |
320ae51f | 1448 | { |
24d2f903 | 1449 | struct blk_mq_tags *tags; |
320ae51f JA |
1450 | unsigned int i, j, entries_per_page, max_order = 4; |
1451 | size_t rq_size, left; | |
1452 | ||
24d2f903 | 1453 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
24391c0d SL |
1454 | set->numa_node, |
1455 | BLK_MQ_FLAG_TO_ALLOC_POLICY(set->flags)); | |
24d2f903 CH |
1456 | if (!tags) |
1457 | return NULL; | |
320ae51f | 1458 | |
24d2f903 CH |
1459 | INIT_LIST_HEAD(&tags->page_list); |
1460 | ||
a5164405 JA |
1461 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1462 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1463 | set->numa_node); | |
24d2f903 CH |
1464 | if (!tags->rqs) { |
1465 | blk_mq_free_tags(tags); | |
1466 | return NULL; | |
1467 | } | |
320ae51f JA |
1468 | |
1469 | /* | |
1470 | * rq_size is the size of the request plus driver payload, rounded | |
1471 | * to the cacheline size | |
1472 | */ | |
24d2f903 | 1473 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1474 | cache_line_size()); |
24d2f903 | 1475 | left = rq_size * set->queue_depth; |
320ae51f | 1476 | |
24d2f903 | 1477 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1478 | int this_order = max_order; |
1479 | struct page *page; | |
1480 | int to_do; | |
1481 | void *p; | |
1482 | ||
1483 | while (left < order_to_size(this_order - 1) && this_order) | |
1484 | this_order--; | |
1485 | ||
1486 | do { | |
a5164405 | 1487 | page = alloc_pages_node(set->numa_node, |
ac211175 | 1488 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO, |
a5164405 | 1489 | this_order); |
320ae51f JA |
1490 | if (page) |
1491 | break; | |
1492 | if (!this_order--) | |
1493 | break; | |
1494 | if (order_to_size(this_order) < rq_size) | |
1495 | break; | |
1496 | } while (1); | |
1497 | ||
1498 | if (!page) | |
24d2f903 | 1499 | goto fail; |
320ae51f JA |
1500 | |
1501 | page->private = this_order; | |
24d2f903 | 1502 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1503 | |
1504 | p = page_address(page); | |
1505 | entries_per_page = order_to_size(this_order) / rq_size; | |
24d2f903 | 1506 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1507 | left -= to_do * rq_size; |
1508 | for (j = 0; j < to_do; j++) { | |
24d2f903 CH |
1509 | tags->rqs[i] = p; |
1510 | if (set->ops->init_request) { | |
1511 | if (set->ops->init_request(set->driver_data, | |
1512 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1513 | set->numa_node)) { |
1514 | tags->rqs[i] = NULL; | |
24d2f903 | 1515 | goto fail; |
a5164405 | 1516 | } |
e9b267d9 CH |
1517 | } |
1518 | ||
320ae51f JA |
1519 | p += rq_size; |
1520 | i++; | |
1521 | } | |
1522 | } | |
24d2f903 | 1523 | return tags; |
320ae51f | 1524 | |
24d2f903 | 1525 | fail: |
24d2f903 CH |
1526 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1527 | return NULL; | |
320ae51f JA |
1528 | } |
1529 | ||
1429d7c9 JA |
1530 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1531 | { | |
1532 | kfree(bitmap->map); | |
1533 | } | |
1534 | ||
1535 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1536 | { | |
1537 | unsigned int bpw = 8, total, num_maps, i; | |
1538 | ||
1539 | bitmap->bits_per_word = bpw; | |
1540 | ||
1541 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1542 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1543 | GFP_KERNEL, node); | |
1544 | if (!bitmap->map) | |
1545 | return -ENOMEM; | |
1546 | ||
1429d7c9 JA |
1547 | total = nr_cpu_ids; |
1548 | for (i = 0; i < num_maps; i++) { | |
1549 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1550 | total -= bitmap->map[i].depth; | |
1551 | } | |
1552 | ||
1553 | return 0; | |
1554 | } | |
1555 | ||
484b4061 JA |
1556 | static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) |
1557 | { | |
1558 | struct request_queue *q = hctx->queue; | |
1559 | struct blk_mq_ctx *ctx; | |
1560 | LIST_HEAD(tmp); | |
1561 | ||
1562 | /* | |
1563 | * Move ctx entries to new CPU, if this one is going away. | |
1564 | */ | |
1565 | ctx = __blk_mq_get_ctx(q, cpu); | |
1566 | ||
1567 | spin_lock(&ctx->lock); | |
1568 | if (!list_empty(&ctx->rq_list)) { | |
1569 | list_splice_init(&ctx->rq_list, &tmp); | |
1570 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1571 | } | |
1572 | spin_unlock(&ctx->lock); | |
1573 | ||
1574 | if (list_empty(&tmp)) | |
1575 | return NOTIFY_OK; | |
1576 | ||
1577 | ctx = blk_mq_get_ctx(q); | |
1578 | spin_lock(&ctx->lock); | |
1579 | ||
1580 | while (!list_empty(&tmp)) { | |
1581 | struct request *rq; | |
1582 | ||
1583 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1584 | rq->mq_ctx = ctx; | |
1585 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1586 | } | |
1587 | ||
1588 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1589 | blk_mq_hctx_mark_pending(hctx, ctx); | |
1590 | ||
1591 | spin_unlock(&ctx->lock); | |
1592 | ||
1593 | blk_mq_run_hw_queue(hctx, true); | |
1594 | blk_mq_put_ctx(ctx); | |
1595 | return NOTIFY_OK; | |
1596 | } | |
1597 | ||
484b4061 JA |
1598 | static int blk_mq_hctx_notify(void *data, unsigned long action, |
1599 | unsigned int cpu) | |
1600 | { | |
1601 | struct blk_mq_hw_ctx *hctx = data; | |
1602 | ||
1603 | if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) | |
1604 | return blk_mq_hctx_cpu_offline(hctx, cpu); | |
2a34c087 ML |
1605 | |
1606 | /* | |
1607 | * In case of CPU online, tags may be reallocated | |
1608 | * in blk_mq_map_swqueue() after mapping is updated. | |
1609 | */ | |
484b4061 JA |
1610 | |
1611 | return NOTIFY_OK; | |
1612 | } | |
1613 | ||
c3b4afca | 1614 | /* hctx->ctxs will be freed in queue's release handler */ |
08e98fc6 ML |
1615 | static void blk_mq_exit_hctx(struct request_queue *q, |
1616 | struct blk_mq_tag_set *set, | |
1617 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
1618 | { | |
f70ced09 ML |
1619 | unsigned flush_start_tag = set->queue_depth; |
1620 | ||
08e98fc6 ML |
1621 | blk_mq_tag_idle(hctx); |
1622 | ||
f70ced09 ML |
1623 | if (set->ops->exit_request) |
1624 | set->ops->exit_request(set->driver_data, | |
1625 | hctx->fq->flush_rq, hctx_idx, | |
1626 | flush_start_tag + hctx_idx); | |
1627 | ||
08e98fc6 ML |
1628 | if (set->ops->exit_hctx) |
1629 | set->ops->exit_hctx(hctx, hctx_idx); | |
1630 | ||
1631 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
f70ced09 | 1632 | blk_free_flush_queue(hctx->fq); |
08e98fc6 ML |
1633 | blk_mq_free_bitmap(&hctx->ctx_map); |
1634 | } | |
1635 | ||
624dbe47 ML |
1636 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1637 | struct blk_mq_tag_set *set, int nr_queue) | |
1638 | { | |
1639 | struct blk_mq_hw_ctx *hctx; | |
1640 | unsigned int i; | |
1641 | ||
1642 | queue_for_each_hw_ctx(q, hctx, i) { | |
1643 | if (i == nr_queue) | |
1644 | break; | |
08e98fc6 | 1645 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 1646 | } |
624dbe47 ML |
1647 | } |
1648 | ||
1649 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1650 | struct blk_mq_tag_set *set) | |
1651 | { | |
1652 | struct blk_mq_hw_ctx *hctx; | |
1653 | unsigned int i; | |
1654 | ||
e09aae7e | 1655 | queue_for_each_hw_ctx(q, hctx, i) |
624dbe47 | 1656 | free_cpumask_var(hctx->cpumask); |
624dbe47 ML |
1657 | } |
1658 | ||
08e98fc6 ML |
1659 | static int blk_mq_init_hctx(struct request_queue *q, |
1660 | struct blk_mq_tag_set *set, | |
1661 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 1662 | { |
08e98fc6 | 1663 | int node; |
f70ced09 | 1664 | unsigned flush_start_tag = set->queue_depth; |
08e98fc6 ML |
1665 | |
1666 | node = hctx->numa_node; | |
1667 | if (node == NUMA_NO_NODE) | |
1668 | node = hctx->numa_node = set->numa_node; | |
1669 | ||
1670 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); | |
1671 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
1672 | spin_lock_init(&hctx->lock); | |
1673 | INIT_LIST_HEAD(&hctx->dispatch); | |
1674 | hctx->queue = q; | |
1675 | hctx->queue_num = hctx_idx; | |
1676 | hctx->flags = set->flags; | |
08e98fc6 ML |
1677 | |
1678 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1679 | blk_mq_hctx_notify, hctx); | |
1680 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1681 | ||
1682 | hctx->tags = set->tags[hctx_idx]; | |
320ae51f JA |
1683 | |
1684 | /* | |
08e98fc6 ML |
1685 | * Allocate space for all possible cpus to avoid allocation at |
1686 | * runtime | |
320ae51f | 1687 | */ |
08e98fc6 ML |
1688 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), |
1689 | GFP_KERNEL, node); | |
1690 | if (!hctx->ctxs) | |
1691 | goto unregister_cpu_notifier; | |
320ae51f | 1692 | |
08e98fc6 ML |
1693 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
1694 | goto free_ctxs; | |
320ae51f | 1695 | |
08e98fc6 | 1696 | hctx->nr_ctx = 0; |
320ae51f | 1697 | |
08e98fc6 ML |
1698 | if (set->ops->init_hctx && |
1699 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
1700 | goto free_bitmap; | |
320ae51f | 1701 | |
f70ced09 ML |
1702 | hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); |
1703 | if (!hctx->fq) | |
1704 | goto exit_hctx; | |
320ae51f | 1705 | |
f70ced09 ML |
1706 | if (set->ops->init_request && |
1707 | set->ops->init_request(set->driver_data, | |
1708 | hctx->fq->flush_rq, hctx_idx, | |
1709 | flush_start_tag + hctx_idx, node)) | |
1710 | goto free_fq; | |
320ae51f | 1711 | |
08e98fc6 | 1712 | return 0; |
320ae51f | 1713 | |
f70ced09 ML |
1714 | free_fq: |
1715 | kfree(hctx->fq); | |
1716 | exit_hctx: | |
1717 | if (set->ops->exit_hctx) | |
1718 | set->ops->exit_hctx(hctx, hctx_idx); | |
08e98fc6 ML |
1719 | free_bitmap: |
1720 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1721 | free_ctxs: | |
1722 | kfree(hctx->ctxs); | |
1723 | unregister_cpu_notifier: | |
1724 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
320ae51f | 1725 | |
08e98fc6 ML |
1726 | return -1; |
1727 | } | |
320ae51f | 1728 | |
08e98fc6 ML |
1729 | static int blk_mq_init_hw_queues(struct request_queue *q, |
1730 | struct blk_mq_tag_set *set) | |
1731 | { | |
1732 | struct blk_mq_hw_ctx *hctx; | |
1733 | unsigned int i; | |
320ae51f | 1734 | |
08e98fc6 ML |
1735 | /* |
1736 | * Initialize hardware queues | |
1737 | */ | |
1738 | queue_for_each_hw_ctx(q, hctx, i) { | |
1739 | if (blk_mq_init_hctx(q, set, hctx, i)) | |
320ae51f JA |
1740 | break; |
1741 | } | |
1742 | ||
1743 | if (i == q->nr_hw_queues) | |
1744 | return 0; | |
1745 | ||
1746 | /* | |
1747 | * Init failed | |
1748 | */ | |
624dbe47 | 1749 | blk_mq_exit_hw_queues(q, set, i); |
320ae51f JA |
1750 | |
1751 | return 1; | |
1752 | } | |
1753 | ||
1754 | static void blk_mq_init_cpu_queues(struct request_queue *q, | |
1755 | unsigned int nr_hw_queues) | |
1756 | { | |
1757 | unsigned int i; | |
1758 | ||
1759 | for_each_possible_cpu(i) { | |
1760 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1761 | struct blk_mq_hw_ctx *hctx; | |
1762 | ||
1763 | memset(__ctx, 0, sizeof(*__ctx)); | |
1764 | __ctx->cpu = i; | |
1765 | spin_lock_init(&__ctx->lock); | |
1766 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1767 | __ctx->queue = q; | |
1768 | ||
1769 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1770 | if (!cpu_online(i)) |
1771 | continue; | |
1772 | ||
e4043dcf | 1773 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1774 | |
320ae51f JA |
1775 | /* |
1776 | * Set local node, IFF we have more than one hw queue. If | |
1777 | * not, we remain on the home node of the device | |
1778 | */ | |
1779 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
1780 | hctx->numa_node = cpu_to_node(i); | |
1781 | } | |
1782 | } | |
1783 | ||
5778322e AM |
1784 | static void blk_mq_map_swqueue(struct request_queue *q, |
1785 | const struct cpumask *online_mask) | |
320ae51f JA |
1786 | { |
1787 | unsigned int i; | |
1788 | struct blk_mq_hw_ctx *hctx; | |
1789 | struct blk_mq_ctx *ctx; | |
2a34c087 | 1790 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 1791 | |
60de074b AM |
1792 | /* |
1793 | * Avoid others reading imcomplete hctx->cpumask through sysfs | |
1794 | */ | |
1795 | mutex_lock(&q->sysfs_lock); | |
1796 | ||
320ae51f | 1797 | queue_for_each_hw_ctx(q, hctx, i) { |
e4043dcf | 1798 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1799 | hctx->nr_ctx = 0; |
1800 | } | |
1801 | ||
1802 | /* | |
1803 | * Map software to hardware queues | |
1804 | */ | |
1805 | queue_for_each_ctx(q, ctx, i) { | |
1806 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
5778322e | 1807 | if (!cpumask_test_cpu(i, online_mask)) |
e4043dcf JA |
1808 | continue; |
1809 | ||
320ae51f | 1810 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1811 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1812 | ctx->index_hw = hctx->nr_ctx; |
1813 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1814 | } | |
506e931f | 1815 | |
60de074b AM |
1816 | mutex_unlock(&q->sysfs_lock); |
1817 | ||
506e931f | 1818 | queue_for_each_hw_ctx(q, hctx, i) { |
889fa31f CY |
1819 | struct blk_mq_ctxmap *map = &hctx->ctx_map; |
1820 | ||
484b4061 | 1821 | /* |
a68aafa5 JA |
1822 | * If no software queues are mapped to this hardware queue, |
1823 | * disable it and free the request entries. | |
484b4061 JA |
1824 | */ |
1825 | if (!hctx->nr_ctx) { | |
484b4061 JA |
1826 | if (set->tags[i]) { |
1827 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1828 | set->tags[i] = NULL; | |
484b4061 | 1829 | } |
2a34c087 | 1830 | hctx->tags = NULL; |
484b4061 JA |
1831 | continue; |
1832 | } | |
1833 | ||
2a34c087 ML |
1834 | /* unmapped hw queue can be remapped after CPU topo changed */ |
1835 | if (!set->tags[i]) | |
1836 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1837 | hctx->tags = set->tags[i]; | |
1838 | WARN_ON(!hctx->tags); | |
1839 | ||
889fa31f CY |
1840 | /* |
1841 | * Set the map size to the number of mapped software queues. | |
1842 | * This is more accurate and more efficient than looping | |
1843 | * over all possibly mapped software queues. | |
1844 | */ | |
569fd0ce | 1845 | map->size = DIV_ROUND_UP(hctx->nr_ctx, map->bits_per_word); |
889fa31f | 1846 | |
484b4061 JA |
1847 | /* |
1848 | * Initialize batch roundrobin counts | |
1849 | */ | |
506e931f JA |
1850 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1851 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1852 | } | |
1356aae0 AM |
1853 | |
1854 | queue_for_each_ctx(q, ctx, i) { | |
5778322e | 1855 | if (!cpumask_test_cpu(i, online_mask)) |
1356aae0 AM |
1856 | continue; |
1857 | ||
1858 | hctx = q->mq_ops->map_queue(q, i); | |
1859 | cpumask_set_cpu(i, hctx->tags->cpumask); | |
1860 | } | |
320ae51f JA |
1861 | } |
1862 | ||
0d2602ca JA |
1863 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |
1864 | { | |
1865 | struct blk_mq_hw_ctx *hctx; | |
1866 | struct request_queue *q; | |
1867 | bool shared; | |
1868 | int i; | |
1869 | ||
1870 | if (set->tag_list.next == set->tag_list.prev) | |
1871 | shared = false; | |
1872 | else | |
1873 | shared = true; | |
1874 | ||
1875 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1876 | blk_mq_freeze_queue(q); | |
1877 | ||
1878 | queue_for_each_hw_ctx(q, hctx, i) { | |
1879 | if (shared) | |
1880 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1881 | else | |
1882 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1883 | } | |
1884 | blk_mq_unfreeze_queue(q); | |
1885 | } | |
1886 | } | |
1887 | ||
1888 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1889 | { | |
1890 | struct blk_mq_tag_set *set = q->tag_set; | |
1891 | ||
0d2602ca JA |
1892 | mutex_lock(&set->tag_list_lock); |
1893 | list_del_init(&q->tag_set_list); | |
1894 | blk_mq_update_tag_set_depth(set); | |
1895 | mutex_unlock(&set->tag_list_lock); | |
0d2602ca JA |
1896 | } |
1897 | ||
1898 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1899 | struct request_queue *q) | |
1900 | { | |
1901 | q->tag_set = set; | |
1902 | ||
1903 | mutex_lock(&set->tag_list_lock); | |
1904 | list_add_tail(&q->tag_set_list, &set->tag_list); | |
1905 | blk_mq_update_tag_set_depth(set); | |
1906 | mutex_unlock(&set->tag_list_lock); | |
1907 | } | |
1908 | ||
e09aae7e ML |
1909 | /* |
1910 | * It is the actual release handler for mq, but we do it from | |
1911 | * request queue's release handler for avoiding use-after-free | |
1912 | * and headache because q->mq_kobj shouldn't have been introduced, | |
1913 | * but we can't group ctx/kctx kobj without it. | |
1914 | */ | |
1915 | void blk_mq_release(struct request_queue *q) | |
1916 | { | |
1917 | struct blk_mq_hw_ctx *hctx; | |
1918 | unsigned int i; | |
1919 | ||
1920 | /* hctx kobj stays in hctx */ | |
c3b4afca ML |
1921 | queue_for_each_hw_ctx(q, hctx, i) { |
1922 | if (!hctx) | |
1923 | continue; | |
1924 | kfree(hctx->ctxs); | |
e09aae7e | 1925 | kfree(hctx); |
c3b4afca | 1926 | } |
e09aae7e | 1927 | |
a723bab3 AM |
1928 | kfree(q->mq_map); |
1929 | q->mq_map = NULL; | |
1930 | ||
e09aae7e ML |
1931 | kfree(q->queue_hw_ctx); |
1932 | ||
1933 | /* ctx kobj stays in queue_ctx */ | |
1934 | free_percpu(q->queue_ctx); | |
1935 | } | |
1936 | ||
24d2f903 | 1937 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
b62c21b7 MS |
1938 | { |
1939 | struct request_queue *uninit_q, *q; | |
1940 | ||
1941 | uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); | |
1942 | if (!uninit_q) | |
1943 | return ERR_PTR(-ENOMEM); | |
1944 | ||
1945 | q = blk_mq_init_allocated_queue(set, uninit_q); | |
1946 | if (IS_ERR(q)) | |
1947 | blk_cleanup_queue(uninit_q); | |
1948 | ||
1949 | return q; | |
1950 | } | |
1951 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1952 | ||
1953 | struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, | |
1954 | struct request_queue *q) | |
320ae51f JA |
1955 | { |
1956 | struct blk_mq_hw_ctx **hctxs; | |
e6cdb092 | 1957 | struct blk_mq_ctx __percpu *ctx; |
f14bbe77 | 1958 | unsigned int *map; |
320ae51f JA |
1959 | int i; |
1960 | ||
320ae51f JA |
1961 | ctx = alloc_percpu(struct blk_mq_ctx); |
1962 | if (!ctx) | |
1963 | return ERR_PTR(-ENOMEM); | |
1964 | ||
24d2f903 CH |
1965 | hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, |
1966 | set->numa_node); | |
320ae51f JA |
1967 | |
1968 | if (!hctxs) | |
1969 | goto err_percpu; | |
1970 | ||
f14bbe77 JA |
1971 | map = blk_mq_make_queue_map(set); |
1972 | if (!map) | |
1973 | goto err_map; | |
1974 | ||
24d2f903 | 1975 | for (i = 0; i < set->nr_hw_queues; i++) { |
f14bbe77 JA |
1976 | int node = blk_mq_hw_queue_to_node(map, i); |
1977 | ||
cdef54dd CH |
1978 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1979 | GFP_KERNEL, node); | |
320ae51f JA |
1980 | if (!hctxs[i]) |
1981 | goto err_hctxs; | |
1982 | ||
a86073e4 JA |
1983 | if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, |
1984 | node)) | |
e4043dcf JA |
1985 | goto err_hctxs; |
1986 | ||
0d2602ca | 1987 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1988 | hctxs[i]->numa_node = node; |
320ae51f JA |
1989 | hctxs[i]->queue_num = i; |
1990 | } | |
1991 | ||
17497acb TH |
1992 | /* |
1993 | * Init percpu_ref in atomic mode so that it's faster to shutdown. | |
1994 | * See blk_register_queue() for details. | |
1995 | */ | |
a34375ef | 1996 | if (percpu_ref_init(&q->mq_usage_counter, blk_mq_usage_counter_release, |
17497acb | 1997 | PERCPU_REF_INIT_ATOMIC, GFP_KERNEL)) |
b62c21b7 | 1998 | goto err_hctxs; |
3d2936f4 | 1999 | |
320ae51f | 2000 | setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); |
e56f698b | 2001 | blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); |
320ae51f JA |
2002 | |
2003 | q->nr_queues = nr_cpu_ids; | |
24d2f903 | 2004 | q->nr_hw_queues = set->nr_hw_queues; |
f14bbe77 | 2005 | q->mq_map = map; |
320ae51f JA |
2006 | |
2007 | q->queue_ctx = ctx; | |
2008 | q->queue_hw_ctx = hctxs; | |
2009 | ||
24d2f903 | 2010 | q->mq_ops = set->ops; |
94eddfbe | 2011 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 2012 | |
05f1dd53 JA |
2013 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
2014 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
2015 | ||
1be036e9 CH |
2016 | q->sg_reserved_size = INT_MAX; |
2017 | ||
6fca6a61 CH |
2018 | INIT_WORK(&q->requeue_work, blk_mq_requeue_work); |
2019 | INIT_LIST_HEAD(&q->requeue_list); | |
2020 | spin_lock_init(&q->requeue_lock); | |
2021 | ||
07068d5b JA |
2022 | if (q->nr_hw_queues > 1) |
2023 | blk_queue_make_request(q, blk_mq_make_request); | |
2024 | else | |
2025 | blk_queue_make_request(q, blk_sq_make_request); | |
2026 | ||
eba71768 JA |
2027 | /* |
2028 | * Do this after blk_queue_make_request() overrides it... | |
2029 | */ | |
2030 | q->nr_requests = set->queue_depth; | |
2031 | ||
24d2f903 CH |
2032 | if (set->ops->complete) |
2033 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 2034 | |
24d2f903 | 2035 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 2036 | |
24d2f903 | 2037 | if (blk_mq_init_hw_queues(q, set)) |
b62c21b7 | 2038 | goto err_hctxs; |
18741986 | 2039 | |
5778322e | 2040 | get_online_cpus(); |
320ae51f | 2041 | mutex_lock(&all_q_mutex); |
320ae51f | 2042 | |
4593fdbe | 2043 | list_add_tail(&q->all_q_node, &all_q_list); |
0d2602ca | 2044 | blk_mq_add_queue_tag_set(set, q); |
5778322e | 2045 | blk_mq_map_swqueue(q, cpu_online_mask); |
484b4061 | 2046 | |
4593fdbe | 2047 | mutex_unlock(&all_q_mutex); |
5778322e | 2048 | put_online_cpus(); |
4593fdbe | 2049 | |
320ae51f | 2050 | return q; |
18741986 | 2051 | |
320ae51f | 2052 | err_hctxs: |
f14bbe77 | 2053 | kfree(map); |
24d2f903 | 2054 | for (i = 0; i < set->nr_hw_queues; i++) { |
320ae51f JA |
2055 | if (!hctxs[i]) |
2056 | break; | |
e4043dcf | 2057 | free_cpumask_var(hctxs[i]->cpumask); |
cdef54dd | 2058 | kfree(hctxs[i]); |
320ae51f | 2059 | } |
f14bbe77 | 2060 | err_map: |
320ae51f JA |
2061 | kfree(hctxs); |
2062 | err_percpu: | |
2063 | free_percpu(ctx); | |
2064 | return ERR_PTR(-ENOMEM); | |
2065 | } | |
b62c21b7 | 2066 | EXPORT_SYMBOL(blk_mq_init_allocated_queue); |
320ae51f JA |
2067 | |
2068 | void blk_mq_free_queue(struct request_queue *q) | |
2069 | { | |
624dbe47 | 2070 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 2071 | |
0e626368 AM |
2072 | mutex_lock(&all_q_mutex); |
2073 | list_del_init(&q->all_q_node); | |
2074 | mutex_unlock(&all_q_mutex); | |
2075 | ||
0d2602ca JA |
2076 | blk_mq_del_queue_tag_set(q); |
2077 | ||
624dbe47 ML |
2078 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
2079 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 2080 | |
add703fd | 2081 | percpu_ref_exit(&q->mq_usage_counter); |
320ae51f | 2082 | } |
320ae51f JA |
2083 | |
2084 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
5778322e AM |
2085 | static void blk_mq_queue_reinit(struct request_queue *q, |
2086 | const struct cpumask *online_mask) | |
320ae51f | 2087 | { |
4ecd4fef | 2088 | WARN_ON_ONCE(!atomic_read(&q->mq_freeze_depth)); |
320ae51f | 2089 | |
67aec14c JA |
2090 | blk_mq_sysfs_unregister(q); |
2091 | ||
5778322e | 2092 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues, online_mask); |
320ae51f JA |
2093 | |
2094 | /* | |
2095 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
2096 | * we should change hctx numa_node according to new topology (this | |
2097 | * involves free and re-allocate memory, worthy doing?) | |
2098 | */ | |
2099 | ||
5778322e | 2100 | blk_mq_map_swqueue(q, online_mask); |
320ae51f | 2101 | |
67aec14c | 2102 | blk_mq_sysfs_register(q); |
320ae51f JA |
2103 | } |
2104 | ||
f618ef7c PG |
2105 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
2106 | unsigned long action, void *hcpu) | |
320ae51f JA |
2107 | { |
2108 | struct request_queue *q; | |
5778322e AM |
2109 | int cpu = (unsigned long)hcpu; |
2110 | /* | |
2111 | * New online cpumask which is going to be set in this hotplug event. | |
2112 | * Declare this cpumasks as global as cpu-hotplug operation is invoked | |
2113 | * one-by-one and dynamically allocating this could result in a failure. | |
2114 | */ | |
2115 | static struct cpumask online_new; | |
320ae51f JA |
2116 | |
2117 | /* | |
5778322e AM |
2118 | * Before hotadded cpu starts handling requests, new mappings must |
2119 | * be established. Otherwise, these requests in hw queue might | |
2120 | * never be dispatched. | |
2121 | * | |
2122 | * For example, there is a single hw queue (hctx) and two CPU queues | |
2123 | * (ctx0 for CPU0, and ctx1 for CPU1). | |
2124 | * | |
2125 | * Now CPU1 is just onlined and a request is inserted into | |
2126 | * ctx1->rq_list and set bit0 in pending bitmap as ctx1->index_hw is | |
2127 | * still zero. | |
2128 | * | |
2129 | * And then while running hw queue, flush_busy_ctxs() finds bit0 is | |
2130 | * set in pending bitmap and tries to retrieve requests in | |
2131 | * hctx->ctxs[0]->rq_list. But htx->ctxs[0] is a pointer to ctx0, | |
2132 | * so the request in ctx1->rq_list is ignored. | |
320ae51f | 2133 | */ |
5778322e AM |
2134 | switch (action & ~CPU_TASKS_FROZEN) { |
2135 | case CPU_DEAD: | |
2136 | case CPU_UP_CANCELED: | |
2137 | cpumask_copy(&online_new, cpu_online_mask); | |
2138 | break; | |
2139 | case CPU_UP_PREPARE: | |
2140 | cpumask_copy(&online_new, cpu_online_mask); | |
2141 | cpumask_set_cpu(cpu, &online_new); | |
2142 | break; | |
2143 | default: | |
320ae51f | 2144 | return NOTIFY_OK; |
5778322e | 2145 | } |
320ae51f JA |
2146 | |
2147 | mutex_lock(&all_q_mutex); | |
f3af020b TH |
2148 | |
2149 | /* | |
2150 | * We need to freeze and reinit all existing queues. Freezing | |
2151 | * involves synchronous wait for an RCU grace period and doing it | |
2152 | * one by one may take a long time. Start freezing all queues in | |
2153 | * one swoop and then wait for the completions so that freezing can | |
2154 | * take place in parallel. | |
2155 | */ | |
2156 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2157 | blk_mq_freeze_queue_start(q); | |
f054b56c | 2158 | list_for_each_entry(q, &all_q_list, all_q_node) { |
f3af020b TH |
2159 | blk_mq_freeze_queue_wait(q); |
2160 | ||
f054b56c ML |
2161 | /* |
2162 | * timeout handler can't touch hw queue during the | |
2163 | * reinitialization | |
2164 | */ | |
2165 | del_timer_sync(&q->timeout); | |
2166 | } | |
2167 | ||
320ae51f | 2168 | list_for_each_entry(q, &all_q_list, all_q_node) |
5778322e | 2169 | blk_mq_queue_reinit(q, &online_new); |
f3af020b TH |
2170 | |
2171 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2172 | blk_mq_unfreeze_queue(q); | |
2173 | ||
320ae51f JA |
2174 | mutex_unlock(&all_q_mutex); |
2175 | return NOTIFY_OK; | |
2176 | } | |
2177 | ||
a5164405 JA |
2178 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
2179 | { | |
2180 | int i; | |
2181 | ||
2182 | for (i = 0; i < set->nr_hw_queues; i++) { | |
2183 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
2184 | if (!set->tags[i]) | |
2185 | goto out_unwind; | |
2186 | } | |
2187 | ||
2188 | return 0; | |
2189 | ||
2190 | out_unwind: | |
2191 | while (--i >= 0) | |
2192 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2193 | ||
a5164405 JA |
2194 | return -ENOMEM; |
2195 | } | |
2196 | ||
2197 | /* | |
2198 | * Allocate the request maps associated with this tag_set. Note that this | |
2199 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
2200 | * will be updated to reflect the allocated depth. | |
2201 | */ | |
2202 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
2203 | { | |
2204 | unsigned int depth; | |
2205 | int err; | |
2206 | ||
2207 | depth = set->queue_depth; | |
2208 | do { | |
2209 | err = __blk_mq_alloc_rq_maps(set); | |
2210 | if (!err) | |
2211 | break; | |
2212 | ||
2213 | set->queue_depth >>= 1; | |
2214 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
2215 | err = -ENOMEM; | |
2216 | break; | |
2217 | } | |
2218 | } while (set->queue_depth); | |
2219 | ||
2220 | if (!set->queue_depth || err) { | |
2221 | pr_err("blk-mq: failed to allocate request map\n"); | |
2222 | return -ENOMEM; | |
2223 | } | |
2224 | ||
2225 | if (depth != set->queue_depth) | |
2226 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2227 | depth, set->queue_depth); | |
2228 | ||
2229 | return 0; | |
2230 | } | |
2231 | ||
f26cdc85 KB |
2232 | struct cpumask *blk_mq_tags_cpumask(struct blk_mq_tags *tags) |
2233 | { | |
2234 | return tags->cpumask; | |
2235 | } | |
2236 | EXPORT_SYMBOL_GPL(blk_mq_tags_cpumask); | |
2237 | ||
a4391c64 JA |
2238 | /* |
2239 | * Alloc a tag set to be associated with one or more request queues. | |
2240 | * May fail with EINVAL for various error conditions. May adjust the | |
2241 | * requested depth down, if if it too large. In that case, the set | |
2242 | * value will be stored in set->queue_depth. | |
2243 | */ | |
24d2f903 CH |
2244 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2245 | { | |
205fb5f5 BVA |
2246 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
2247 | ||
24d2f903 CH |
2248 | if (!set->nr_hw_queues) |
2249 | return -EINVAL; | |
a4391c64 | 2250 | if (!set->queue_depth) |
24d2f903 CH |
2251 | return -EINVAL; |
2252 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2253 | return -EINVAL; | |
2254 | ||
f9018ac9 | 2255 | if (!set->ops->queue_rq || !set->ops->map_queue) |
24d2f903 CH |
2256 | return -EINVAL; |
2257 | ||
a4391c64 JA |
2258 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2259 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2260 | BLK_MQ_MAX_DEPTH); | |
2261 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2262 | } | |
24d2f903 | 2263 | |
6637fadf SL |
2264 | /* |
2265 | * If a crashdump is active, then we are potentially in a very | |
2266 | * memory constrained environment. Limit us to 1 queue and | |
2267 | * 64 tags to prevent using too much memory. | |
2268 | */ | |
2269 | if (is_kdump_kernel()) { | |
2270 | set->nr_hw_queues = 1; | |
2271 | set->queue_depth = min(64U, set->queue_depth); | |
2272 | } | |
2273 | ||
48479005 ML |
2274 | set->tags = kmalloc_node(set->nr_hw_queues * |
2275 | sizeof(struct blk_mq_tags *), | |
24d2f903 CH |
2276 | GFP_KERNEL, set->numa_node); |
2277 | if (!set->tags) | |
a5164405 | 2278 | return -ENOMEM; |
24d2f903 | 2279 | |
a5164405 JA |
2280 | if (blk_mq_alloc_rq_maps(set)) |
2281 | goto enomem; | |
24d2f903 | 2282 | |
0d2602ca JA |
2283 | mutex_init(&set->tag_list_lock); |
2284 | INIT_LIST_HEAD(&set->tag_list); | |
2285 | ||
24d2f903 | 2286 | return 0; |
a5164405 | 2287 | enomem: |
5676e7b6 RE |
2288 | kfree(set->tags); |
2289 | set->tags = NULL; | |
24d2f903 CH |
2290 | return -ENOMEM; |
2291 | } | |
2292 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2293 | ||
2294 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2295 | { | |
2296 | int i; | |
2297 | ||
484b4061 | 2298 | for (i = 0; i < set->nr_hw_queues; i++) { |
f42d79ab | 2299 | if (set->tags[i]) |
484b4061 JA |
2300 | blk_mq_free_rq_map(set, set->tags[i], i); |
2301 | } | |
2302 | ||
981bd189 | 2303 | kfree(set->tags); |
5676e7b6 | 2304 | set->tags = NULL; |
24d2f903 CH |
2305 | } |
2306 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2307 | ||
e3a2b3f9 JA |
2308 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2309 | { | |
2310 | struct blk_mq_tag_set *set = q->tag_set; | |
2311 | struct blk_mq_hw_ctx *hctx; | |
2312 | int i, ret; | |
2313 | ||
2314 | if (!set || nr > set->queue_depth) | |
2315 | return -EINVAL; | |
2316 | ||
2317 | ret = 0; | |
2318 | queue_for_each_hw_ctx(q, hctx, i) { | |
2319 | ret = blk_mq_tag_update_depth(hctx->tags, nr); | |
2320 | if (ret) | |
2321 | break; | |
2322 | } | |
2323 | ||
2324 | if (!ret) | |
2325 | q->nr_requests = nr; | |
2326 | ||
2327 | return ret; | |
2328 | } | |
2329 | ||
676141e4 JA |
2330 | void blk_mq_disable_hotplug(void) |
2331 | { | |
2332 | mutex_lock(&all_q_mutex); | |
2333 | } | |
2334 | ||
2335 | void blk_mq_enable_hotplug(void) | |
2336 | { | |
2337 | mutex_unlock(&all_q_mutex); | |
2338 | } | |
2339 | ||
320ae51f JA |
2340 | static int __init blk_mq_init(void) |
2341 | { | |
320ae51f JA |
2342 | blk_mq_cpu_init(); |
2343 | ||
add703fd | 2344 | hotcpu_notifier(blk_mq_queue_reinit_notify, 0); |
320ae51f JA |
2345 | |
2346 | return 0; | |
2347 | } | |
2348 | subsys_initcall(blk_mq_init); |