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 | ||
1429d7c9 JA |
44 | for (i = 0; i < hctx->ctx_map.map_size; i++) |
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 | ||
320ae51f JA |
80 | static int blk_mq_queue_enter(struct request_queue *q) |
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 | |
add703fd TH |
88 | ret = wait_event_interruptible(q->mq_freeze_wq, |
89 | !q->mq_freeze_depth || blk_queue_dying(q)); | |
90 | if (blk_queue_dying(q)) | |
91 | return -ENODEV; | |
92 | if (ret) | |
93 | return ret; | |
94 | } | |
320ae51f JA |
95 | } |
96 | ||
97 | static void blk_mq_queue_exit(struct request_queue *q) | |
98 | { | |
add703fd TH |
99 | percpu_ref_put(&q->mq_usage_counter); |
100 | } | |
101 | ||
102 | static void blk_mq_usage_counter_release(struct percpu_ref *ref) | |
103 | { | |
104 | struct request_queue *q = | |
105 | container_of(ref, struct request_queue, mq_usage_counter); | |
106 | ||
107 | wake_up_all(&q->mq_freeze_wq); | |
320ae51f JA |
108 | } |
109 | ||
b4c6a028 | 110 | void blk_mq_freeze_queue_start(struct request_queue *q) |
43a5e4e2 | 111 | { |
cddd5d17 TH |
112 | bool freeze; |
113 | ||
72d6f02a | 114 | spin_lock_irq(q->queue_lock); |
cddd5d17 | 115 | freeze = !q->mq_freeze_depth++; |
72d6f02a TH |
116 | spin_unlock_irq(q->queue_lock); |
117 | ||
cddd5d17 | 118 | if (freeze) { |
9eca8046 | 119 | percpu_ref_kill(&q->mq_usage_counter); |
cddd5d17 TH |
120 | blk_mq_run_queues(q, false); |
121 | } | |
f3af020b | 122 | } |
b4c6a028 | 123 | EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start); |
f3af020b TH |
124 | |
125 | static void blk_mq_freeze_queue_wait(struct request_queue *q) | |
126 | { | |
add703fd | 127 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); |
43a5e4e2 ML |
128 | } |
129 | ||
f3af020b TH |
130 | /* |
131 | * Guarantee no request is in use, so we can change any data structure of | |
132 | * the queue afterward. | |
133 | */ | |
134 | void blk_mq_freeze_queue(struct request_queue *q) | |
135 | { | |
136 | blk_mq_freeze_queue_start(q); | |
137 | blk_mq_freeze_queue_wait(q); | |
138 | } | |
139 | ||
b4c6a028 | 140 | void blk_mq_unfreeze_queue(struct request_queue *q) |
320ae51f | 141 | { |
cddd5d17 | 142 | bool wake; |
320ae51f JA |
143 | |
144 | spin_lock_irq(q->queue_lock); | |
780db207 TH |
145 | wake = !--q->mq_freeze_depth; |
146 | WARN_ON_ONCE(q->mq_freeze_depth < 0); | |
320ae51f | 147 | spin_unlock_irq(q->queue_lock); |
add703fd TH |
148 | if (wake) { |
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); | |
163 | } | |
164 | ||
320ae51f JA |
165 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) |
166 | { | |
167 | return blk_mq_has_free_tags(hctx->tags); | |
168 | } | |
169 | EXPORT_SYMBOL(blk_mq_can_queue); | |
170 | ||
94eddfbe JA |
171 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
172 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 173 | { |
94eddfbe JA |
174 | if (blk_queue_io_stat(q)) |
175 | rw_flags |= REQ_IO_STAT; | |
176 | ||
af76e555 CH |
177 | INIT_LIST_HEAD(&rq->queuelist); |
178 | /* csd/requeue_work/fifo_time is initialized before use */ | |
179 | rq->q = q; | |
320ae51f | 180 | rq->mq_ctx = ctx; |
0d2602ca | 181 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
182 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
183 | rq->cpu = -1; | |
af76e555 CH |
184 | INIT_HLIST_NODE(&rq->hash); |
185 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
186 | rq->rq_disk = NULL; |
187 | rq->part = NULL; | |
3ee32372 | 188 | rq->start_time = jiffies; |
af76e555 CH |
189 | #ifdef CONFIG_BLK_CGROUP |
190 | rq->rl = NULL; | |
0fec08b4 | 191 | set_start_time_ns(rq); |
af76e555 CH |
192 | rq->io_start_time_ns = 0; |
193 | #endif | |
194 | rq->nr_phys_segments = 0; | |
195 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
196 | rq->nr_integrity_segments = 0; | |
197 | #endif | |
af76e555 CH |
198 | rq->special = NULL; |
199 | /* tag was already set */ | |
200 | rq->errors = 0; | |
af76e555 | 201 | |
6f4a1626 TB |
202 | rq->cmd = rq->__cmd; |
203 | ||
af76e555 CH |
204 | rq->extra_len = 0; |
205 | rq->sense_len = 0; | |
206 | rq->resid_len = 0; | |
207 | rq->sense = NULL; | |
208 | ||
af76e555 | 209 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
210 | rq->timeout = 0; |
211 | ||
af76e555 CH |
212 | rq->end_io = NULL; |
213 | rq->end_io_data = NULL; | |
214 | rq->next_rq = NULL; | |
215 | ||
320ae51f JA |
216 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
217 | } | |
218 | ||
5dee8577 | 219 | static struct request * |
cb96a42c | 220 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) |
5dee8577 CH |
221 | { |
222 | struct request *rq; | |
223 | unsigned int tag; | |
224 | ||
cb96a42c | 225 | tag = blk_mq_get_tag(data); |
5dee8577 | 226 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 227 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 228 | |
cb96a42c | 229 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 230 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 231 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
232 | } |
233 | ||
234 | rq->tag = tag; | |
cb96a42c | 235 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); |
5dee8577 CH |
236 | return rq; |
237 | } | |
238 | ||
239 | return NULL; | |
240 | } | |
241 | ||
4ce01dd1 CH |
242 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp, |
243 | bool reserved) | |
320ae51f | 244 | { |
d852564f CH |
245 | struct blk_mq_ctx *ctx; |
246 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 247 | struct request *rq; |
cb96a42c | 248 | struct blk_mq_alloc_data alloc_data; |
a492f075 | 249 | int ret; |
320ae51f | 250 | |
a492f075 JL |
251 | ret = blk_mq_queue_enter(q); |
252 | if (ret) | |
253 | return ERR_PTR(ret); | |
320ae51f | 254 | |
d852564f CH |
255 | ctx = blk_mq_get_ctx(q); |
256 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
257 | blk_mq_set_alloc_data(&alloc_data, q, gfp & ~__GFP_WAIT, |
258 | reserved, ctx, hctx); | |
d852564f | 259 | |
cb96a42c | 260 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
d852564f CH |
261 | if (!rq && (gfp & __GFP_WAIT)) { |
262 | __blk_mq_run_hw_queue(hctx); | |
263 | blk_mq_put_ctx(ctx); | |
264 | ||
265 | ctx = blk_mq_get_ctx(q); | |
266 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
267 | blk_mq_set_alloc_data(&alloc_data, q, gfp, reserved, ctx, |
268 | hctx); | |
269 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
270 | ctx = alloc_data.ctx; | |
d852564f CH |
271 | } |
272 | blk_mq_put_ctx(ctx); | |
c76541a9 KB |
273 | if (!rq) { |
274 | blk_mq_queue_exit(q); | |
a492f075 | 275 | return ERR_PTR(-EWOULDBLOCK); |
c76541a9 | 276 | } |
320ae51f JA |
277 | return rq; |
278 | } | |
4bb659b1 | 279 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 280 | |
320ae51f JA |
281 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
282 | struct blk_mq_ctx *ctx, struct request *rq) | |
283 | { | |
284 | const int tag = rq->tag; | |
285 | struct request_queue *q = rq->q; | |
286 | ||
0d2602ca JA |
287 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
288 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 289 | rq->cmd_flags = 0; |
0d2602ca | 290 | |
af76e555 | 291 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 292 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
320ae51f JA |
293 | blk_mq_queue_exit(q); |
294 | } | |
295 | ||
7c7f2f2b | 296 | void blk_mq_free_hctx_request(struct blk_mq_hw_ctx *hctx, struct request *rq) |
320ae51f JA |
297 | { |
298 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
320ae51f JA |
299 | |
300 | ctx->rq_completed[rq_is_sync(rq)]++; | |
320ae51f | 301 | __blk_mq_free_request(hctx, ctx, rq); |
7c7f2f2b JA |
302 | |
303 | } | |
304 | EXPORT_SYMBOL_GPL(blk_mq_free_hctx_request); | |
305 | ||
306 | void blk_mq_free_request(struct request *rq) | |
307 | { | |
308 | struct blk_mq_hw_ctx *hctx; | |
309 | struct request_queue *q = rq->q; | |
310 | ||
311 | hctx = q->mq_ops->map_queue(q, rq->mq_ctx->cpu); | |
312 | blk_mq_free_hctx_request(hctx, rq); | |
320ae51f | 313 | } |
1a3b595a | 314 | EXPORT_SYMBOL_GPL(blk_mq_free_request); |
320ae51f | 315 | |
c8a446ad | 316 | inline void __blk_mq_end_request(struct request *rq, int error) |
320ae51f | 317 | { |
0d11e6ac ML |
318 | blk_account_io_done(rq); |
319 | ||
91b63639 | 320 | if (rq->end_io) { |
320ae51f | 321 | rq->end_io(rq, error); |
91b63639 CH |
322 | } else { |
323 | if (unlikely(blk_bidi_rq(rq))) | |
324 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 325 | blk_mq_free_request(rq); |
91b63639 | 326 | } |
320ae51f | 327 | } |
c8a446ad | 328 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 329 | |
c8a446ad | 330 | void blk_mq_end_request(struct request *rq, int error) |
63151a44 CH |
331 | { |
332 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
333 | BUG(); | |
c8a446ad | 334 | __blk_mq_end_request(rq, error); |
63151a44 | 335 | } |
c8a446ad | 336 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 337 | |
30a91cb4 | 338 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 339 | { |
3d6efbf6 | 340 | struct request *rq = data; |
320ae51f | 341 | |
30a91cb4 | 342 | rq->q->softirq_done_fn(rq); |
320ae51f | 343 | } |
320ae51f | 344 | |
ed851860 | 345 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
346 | { |
347 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 348 | bool shared = false; |
320ae51f JA |
349 | int cpu; |
350 | ||
38535201 | 351 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
352 | rq->q->softirq_done_fn(rq); |
353 | return; | |
354 | } | |
320ae51f JA |
355 | |
356 | cpu = get_cpu(); | |
38535201 CH |
357 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
358 | shared = cpus_share_cache(cpu, ctx->cpu); | |
359 | ||
360 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 361 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
362 | rq->csd.info = rq; |
363 | rq->csd.flags = 0; | |
c46fff2a | 364 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 365 | } else { |
30a91cb4 | 366 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 367 | } |
320ae51f JA |
368 | put_cpu(); |
369 | } | |
30a91cb4 | 370 | |
ed851860 JA |
371 | void __blk_mq_complete_request(struct request *rq) |
372 | { | |
373 | struct request_queue *q = rq->q; | |
374 | ||
375 | if (!q->softirq_done_fn) | |
c8a446ad | 376 | blk_mq_end_request(rq, rq->errors); |
ed851860 JA |
377 | else |
378 | blk_mq_ipi_complete_request(rq); | |
379 | } | |
380 | ||
30a91cb4 CH |
381 | /** |
382 | * blk_mq_complete_request - end I/O on a request | |
383 | * @rq: the request being processed | |
384 | * | |
385 | * Description: | |
386 | * Ends all I/O on a request. It does not handle partial completions. | |
387 | * The actual completion happens out-of-order, through a IPI handler. | |
388 | **/ | |
389 | void blk_mq_complete_request(struct request *rq) | |
390 | { | |
95f09684 JA |
391 | struct request_queue *q = rq->q; |
392 | ||
393 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 394 | return; |
ed851860 JA |
395 | if (!blk_mark_rq_complete(rq)) |
396 | __blk_mq_complete_request(rq); | |
30a91cb4 CH |
397 | } |
398 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 399 | |
e2490073 | 400 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
401 | { |
402 | struct request_queue *q = rq->q; | |
403 | ||
404 | trace_block_rq_issue(q, rq); | |
405 | ||
742ee69b | 406 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
407 | if (unlikely(blk_bidi_rq(rq))) |
408 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 409 | |
2b8393b4 | 410 | blk_add_timer(rq); |
87ee7b11 | 411 | |
538b7534 JA |
412 | /* |
413 | * Ensure that ->deadline is visible before set the started | |
414 | * flag and clear the completed flag. | |
415 | */ | |
416 | smp_mb__before_atomic(); | |
417 | ||
87ee7b11 JA |
418 | /* |
419 | * Mark us as started and clear complete. Complete might have been | |
420 | * set if requeue raced with timeout, which then marked it as | |
421 | * complete. So be sure to clear complete again when we start | |
422 | * the request, otherwise we'll ignore the completion event. | |
423 | */ | |
4b570521 JA |
424 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
425 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
426 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
427 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
428 | |
429 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
430 | /* | |
431 | * Make sure space for the drain appears. We know we can do | |
432 | * this because max_hw_segments has been adjusted to be one | |
433 | * fewer than the device can handle. | |
434 | */ | |
435 | rq->nr_phys_segments++; | |
436 | } | |
320ae51f | 437 | } |
e2490073 | 438 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 439 | |
ed0791b2 | 440 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
441 | { |
442 | struct request_queue *q = rq->q; | |
443 | ||
444 | trace_block_rq_requeue(q, rq); | |
49f5baa5 | 445 | |
e2490073 CH |
446 | if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
447 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
448 | rq->nr_phys_segments--; | |
449 | } | |
320ae51f JA |
450 | } |
451 | ||
ed0791b2 CH |
452 | void blk_mq_requeue_request(struct request *rq) |
453 | { | |
ed0791b2 | 454 | __blk_mq_requeue_request(rq); |
ed0791b2 | 455 | |
ed0791b2 | 456 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 457 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
458 | } |
459 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
460 | ||
6fca6a61 CH |
461 | static void blk_mq_requeue_work(struct work_struct *work) |
462 | { | |
463 | struct request_queue *q = | |
464 | container_of(work, struct request_queue, requeue_work); | |
465 | LIST_HEAD(rq_list); | |
466 | struct request *rq, *next; | |
467 | unsigned long flags; | |
468 | ||
469 | spin_lock_irqsave(&q->requeue_lock, flags); | |
470 | list_splice_init(&q->requeue_list, &rq_list); | |
471 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
472 | ||
473 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
474 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
475 | continue; | |
476 | ||
477 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
478 | list_del_init(&rq->queuelist); | |
479 | blk_mq_insert_request(rq, true, false, false); | |
480 | } | |
481 | ||
482 | while (!list_empty(&rq_list)) { | |
483 | rq = list_entry(rq_list.next, struct request, queuelist); | |
484 | list_del_init(&rq->queuelist); | |
485 | blk_mq_insert_request(rq, false, false, false); | |
486 | } | |
487 | ||
8b957415 JA |
488 | /* |
489 | * Use the start variant of queue running here, so that running | |
490 | * the requeue work will kick stopped queues. | |
491 | */ | |
492 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
493 | } |
494 | ||
495 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
496 | { | |
497 | struct request_queue *q = rq->q; | |
498 | unsigned long flags; | |
499 | ||
500 | /* | |
501 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
502 | * request head insertation from the workqueue. | |
503 | */ | |
504 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
505 | ||
506 | spin_lock_irqsave(&q->requeue_lock, flags); | |
507 | if (at_head) { | |
508 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
509 | list_add(&rq->queuelist, &q->requeue_list); | |
510 | } else { | |
511 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
512 | } | |
513 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
514 | } | |
515 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
516 | ||
517 | void blk_mq_kick_requeue_list(struct request_queue *q) | |
518 | { | |
519 | kblockd_schedule_work(&q->requeue_work); | |
520 | } | |
521 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
522 | ||
7c94e1c1 ML |
523 | static inline bool is_flush_request(struct request *rq, |
524 | struct blk_flush_queue *fq, unsigned int tag) | |
24d2f903 | 525 | { |
0e62f51f | 526 | return ((rq->cmd_flags & REQ_FLUSH_SEQ) && |
7c94e1c1 | 527 | fq->flush_rq->tag == tag); |
0e62f51f JA |
528 | } |
529 | ||
530 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) | |
531 | { | |
532 | struct request *rq = tags->rqs[tag]; | |
e97c293c ML |
533 | /* mq_ctx of flush rq is always cloned from the corresponding req */ |
534 | struct blk_flush_queue *fq = blk_get_flush_queue(rq->q, rq->mq_ctx); | |
22302375 | 535 | |
7c94e1c1 | 536 | if (!is_flush_request(rq, fq, tag)) |
0e62f51f | 537 | return rq; |
22302375 | 538 | |
7c94e1c1 | 539 | return fq->flush_rq; |
24d2f903 CH |
540 | } |
541 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
542 | ||
320ae51f | 543 | struct blk_mq_timeout_data { |
46f92d42 CH |
544 | unsigned long next; |
545 | unsigned int next_set; | |
320ae51f JA |
546 | }; |
547 | ||
90415837 | 548 | void blk_mq_rq_timed_out(struct request *req, bool reserved) |
320ae51f | 549 | { |
46f92d42 CH |
550 | struct blk_mq_ops *ops = req->q->mq_ops; |
551 | enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER; | |
87ee7b11 JA |
552 | |
553 | /* | |
554 | * We know that complete is set at this point. If STARTED isn't set | |
555 | * anymore, then the request isn't active and the "timeout" should | |
556 | * just be ignored. This can happen due to the bitflag ordering. | |
557 | * Timeout first checks if STARTED is set, and if it is, assumes | |
558 | * the request is active. But if we race with completion, then | |
559 | * we both flags will get cleared. So check here again, and ignore | |
560 | * a timeout event with a request that isn't active. | |
561 | */ | |
46f92d42 CH |
562 | if (!test_bit(REQ_ATOM_STARTED, &req->atomic_flags)) |
563 | return; | |
87ee7b11 | 564 | |
46f92d42 | 565 | if (ops->timeout) |
0152fb6b | 566 | ret = ops->timeout(req, reserved); |
46f92d42 CH |
567 | |
568 | switch (ret) { | |
569 | case BLK_EH_HANDLED: | |
570 | __blk_mq_complete_request(req); | |
571 | break; | |
572 | case BLK_EH_RESET_TIMER: | |
573 | blk_add_timer(req); | |
574 | blk_clear_rq_complete(req); | |
575 | break; | |
576 | case BLK_EH_NOT_HANDLED: | |
577 | break; | |
578 | default: | |
579 | printk(KERN_ERR "block: bad eh return: %d\n", ret); | |
580 | break; | |
581 | } | |
87ee7b11 | 582 | } |
81481eb4 | 583 | |
81481eb4 CH |
584 | static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, |
585 | struct request *rq, void *priv, bool reserved) | |
586 | { | |
587 | struct blk_mq_timeout_data *data = priv; | |
87ee7b11 | 588 | |
46f92d42 CH |
589 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
590 | return; | |
87ee7b11 | 591 | |
46f92d42 CH |
592 | if (time_after_eq(jiffies, rq->deadline)) { |
593 | if (!blk_mark_rq_complete(rq)) | |
0152fb6b | 594 | blk_mq_rq_timed_out(rq, reserved); |
46f92d42 CH |
595 | } else if (!data->next_set || time_after(data->next, rq->deadline)) { |
596 | data->next = rq->deadline; | |
597 | data->next_set = 1; | |
598 | } | |
87ee7b11 JA |
599 | } |
600 | ||
81481eb4 | 601 | static void blk_mq_rq_timer(unsigned long priv) |
320ae51f | 602 | { |
81481eb4 CH |
603 | struct request_queue *q = (struct request_queue *)priv; |
604 | struct blk_mq_timeout_data data = { | |
605 | .next = 0, | |
606 | .next_set = 0, | |
607 | }; | |
320ae51f | 608 | struct blk_mq_hw_ctx *hctx; |
81481eb4 | 609 | int i; |
320ae51f | 610 | |
484b4061 JA |
611 | queue_for_each_hw_ctx(q, hctx, i) { |
612 | /* | |
613 | * If not software queues are currently mapped to this | |
614 | * hardware queue, there's nothing to check | |
615 | */ | |
19c66e59 | 616 | if (!blk_mq_hw_queue_mapped(hctx)) |
484b4061 JA |
617 | continue; |
618 | ||
81481eb4 | 619 | blk_mq_tag_busy_iter(hctx, blk_mq_check_expired, &data); |
484b4061 | 620 | } |
320ae51f | 621 | |
81481eb4 CH |
622 | if (data.next_set) { |
623 | data.next = blk_rq_timeout(round_jiffies_up(data.next)); | |
624 | mod_timer(&q->timeout, data.next); | |
0d2602ca JA |
625 | } else { |
626 | queue_for_each_hw_ctx(q, hctx, i) | |
627 | blk_mq_tag_idle(hctx); | |
628 | } | |
320ae51f JA |
629 | } |
630 | ||
631 | /* | |
632 | * Reverse check our software queue for entries that we could potentially | |
633 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
634 | * too much time checking for merges. | |
635 | */ | |
636 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
637 | struct blk_mq_ctx *ctx, struct bio *bio) | |
638 | { | |
639 | struct request *rq; | |
640 | int checked = 8; | |
641 | ||
642 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
643 | int el_ret; | |
644 | ||
645 | if (!checked--) | |
646 | break; | |
647 | ||
648 | if (!blk_rq_merge_ok(rq, bio)) | |
649 | continue; | |
650 | ||
651 | el_ret = blk_try_merge(rq, bio); | |
652 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
653 | if (bio_attempt_back_merge(q, rq, bio)) { | |
654 | ctx->rq_merged++; | |
655 | return true; | |
656 | } | |
657 | break; | |
658 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
659 | if (bio_attempt_front_merge(q, rq, bio)) { | |
660 | ctx->rq_merged++; | |
661 | return true; | |
662 | } | |
663 | break; | |
664 | } | |
665 | } | |
666 | ||
667 | return false; | |
668 | } | |
669 | ||
1429d7c9 JA |
670 | /* |
671 | * Process software queues that have been marked busy, splicing them | |
672 | * to the for-dispatch | |
673 | */ | |
674 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
675 | { | |
676 | struct blk_mq_ctx *ctx; | |
677 | int i; | |
678 | ||
679 | for (i = 0; i < hctx->ctx_map.map_size; i++) { | |
680 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; | |
681 | unsigned int off, bit; | |
682 | ||
683 | if (!bm->word) | |
684 | continue; | |
685 | ||
686 | bit = 0; | |
687 | off = i * hctx->ctx_map.bits_per_word; | |
688 | do { | |
689 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
690 | if (bit >= bm->depth) | |
691 | break; | |
692 | ||
693 | ctx = hctx->ctxs[bit + off]; | |
694 | clear_bit(bit, &bm->word); | |
695 | spin_lock(&ctx->lock); | |
696 | list_splice_tail_init(&ctx->rq_list, list); | |
697 | spin_unlock(&ctx->lock); | |
698 | ||
699 | bit++; | |
700 | } while (1); | |
701 | } | |
702 | } | |
703 | ||
320ae51f JA |
704 | /* |
705 | * Run this hardware queue, pulling any software queues mapped to it in. | |
706 | * Note that this function currently has various problems around ordering | |
707 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
708 | * items on the hctx->dispatch list. Ignore that for now. | |
709 | */ | |
710 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
711 | { | |
712 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
713 | struct request *rq; |
714 | LIST_HEAD(rq_list); | |
74c45052 JA |
715 | LIST_HEAD(driver_list); |
716 | struct list_head *dptr; | |
1429d7c9 | 717 | int queued; |
320ae51f | 718 | |
fd1270d5 | 719 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 720 | |
5d12f905 | 721 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
722 | return; |
723 | ||
724 | hctx->run++; | |
725 | ||
726 | /* | |
727 | * Touch any software queue that has pending entries. | |
728 | */ | |
1429d7c9 | 729 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
730 | |
731 | /* | |
732 | * If we have previous entries on our dispatch list, grab them | |
733 | * and stuff them at the front for more fair dispatch. | |
734 | */ | |
735 | if (!list_empty_careful(&hctx->dispatch)) { | |
736 | spin_lock(&hctx->lock); | |
737 | if (!list_empty(&hctx->dispatch)) | |
738 | list_splice_init(&hctx->dispatch, &rq_list); | |
739 | spin_unlock(&hctx->lock); | |
740 | } | |
741 | ||
74c45052 JA |
742 | /* |
743 | * Start off with dptr being NULL, so we start the first request | |
744 | * immediately, even if we have more pending. | |
745 | */ | |
746 | dptr = NULL; | |
747 | ||
320ae51f JA |
748 | /* |
749 | * Now process all the entries, sending them to the driver. | |
750 | */ | |
1429d7c9 | 751 | queued = 0; |
320ae51f | 752 | while (!list_empty(&rq_list)) { |
74c45052 | 753 | struct blk_mq_queue_data bd; |
320ae51f JA |
754 | int ret; |
755 | ||
756 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
757 | list_del_init(&rq->queuelist); | |
320ae51f | 758 | |
74c45052 JA |
759 | bd.rq = rq; |
760 | bd.list = dptr; | |
761 | bd.last = list_empty(&rq_list); | |
762 | ||
763 | ret = q->mq_ops->queue_rq(hctx, &bd); | |
320ae51f JA |
764 | switch (ret) { |
765 | case BLK_MQ_RQ_QUEUE_OK: | |
766 | queued++; | |
767 | continue; | |
768 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 769 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 770 | __blk_mq_requeue_request(rq); |
320ae51f JA |
771 | break; |
772 | default: | |
773 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 774 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 775 | rq->errors = -EIO; |
c8a446ad | 776 | blk_mq_end_request(rq, rq->errors); |
320ae51f JA |
777 | break; |
778 | } | |
779 | ||
780 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
781 | break; | |
74c45052 JA |
782 | |
783 | /* | |
784 | * We've done the first request. If we have more than 1 | |
785 | * left in the list, set dptr to defer issue. | |
786 | */ | |
787 | if (!dptr && rq_list.next != rq_list.prev) | |
788 | dptr = &driver_list; | |
320ae51f JA |
789 | } |
790 | ||
791 | if (!queued) | |
792 | hctx->dispatched[0]++; | |
793 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
794 | hctx->dispatched[ilog2(queued) + 1]++; | |
795 | ||
796 | /* | |
797 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
798 | * that is where we will continue on next queue run. | |
799 | */ | |
800 | if (!list_empty(&rq_list)) { | |
801 | spin_lock(&hctx->lock); | |
802 | list_splice(&rq_list, &hctx->dispatch); | |
803 | spin_unlock(&hctx->lock); | |
804 | } | |
805 | } | |
806 | ||
506e931f JA |
807 | /* |
808 | * It'd be great if the workqueue API had a way to pass | |
809 | * in a mask and had some smarts for more clever placement. | |
810 | * For now we just round-robin here, switching for every | |
811 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
812 | */ | |
813 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
814 | { | |
b657d7e6 CH |
815 | if (hctx->queue->nr_hw_queues == 1) |
816 | return WORK_CPU_UNBOUND; | |
506e931f JA |
817 | |
818 | if (--hctx->next_cpu_batch <= 0) { | |
b657d7e6 | 819 | int cpu = hctx->next_cpu, next_cpu; |
506e931f JA |
820 | |
821 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
822 | if (next_cpu >= nr_cpu_ids) | |
823 | next_cpu = cpumask_first(hctx->cpumask); | |
824 | ||
825 | hctx->next_cpu = next_cpu; | |
826 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
b657d7e6 CH |
827 | |
828 | return cpu; | |
506e931f JA |
829 | } |
830 | ||
b657d7e6 | 831 | return hctx->next_cpu; |
506e931f JA |
832 | } |
833 | ||
320ae51f JA |
834 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
835 | { | |
19c66e59 ML |
836 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state) || |
837 | !blk_mq_hw_queue_mapped(hctx))) | |
320ae51f JA |
838 | return; |
839 | ||
398205b8 | 840 | if (!async) { |
2a90d4aa PB |
841 | int cpu = get_cpu(); |
842 | if (cpumask_test_cpu(cpu, hctx->cpumask)) { | |
398205b8 | 843 | __blk_mq_run_hw_queue(hctx); |
2a90d4aa | 844 | put_cpu(); |
398205b8 PB |
845 | return; |
846 | } | |
e4043dcf | 847 | |
2a90d4aa | 848 | put_cpu(); |
e4043dcf | 849 | } |
398205b8 | 850 | |
b657d7e6 CH |
851 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
852 | &hctx->run_work, 0); | |
320ae51f JA |
853 | } |
854 | ||
855 | void blk_mq_run_queues(struct request_queue *q, bool async) | |
856 | { | |
857 | struct blk_mq_hw_ctx *hctx; | |
858 | int i; | |
859 | ||
860 | queue_for_each_hw_ctx(q, hctx, i) { | |
861 | if ((!blk_mq_hctx_has_pending(hctx) && | |
862 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 863 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
864 | continue; |
865 | ||
866 | blk_mq_run_hw_queue(hctx, async); | |
867 | } | |
868 | } | |
869 | EXPORT_SYMBOL(blk_mq_run_queues); | |
870 | ||
871 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
872 | { | |
70f4db63 CH |
873 | cancel_delayed_work(&hctx->run_work); |
874 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
875 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
876 | } | |
877 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
878 | ||
280d45f6 CH |
879 | void blk_mq_stop_hw_queues(struct request_queue *q) |
880 | { | |
881 | struct blk_mq_hw_ctx *hctx; | |
882 | int i; | |
883 | ||
884 | queue_for_each_hw_ctx(q, hctx, i) | |
885 | blk_mq_stop_hw_queue(hctx); | |
886 | } | |
887 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
888 | ||
320ae51f JA |
889 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
890 | { | |
891 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 892 | |
0ffbce80 | 893 | blk_mq_run_hw_queue(hctx, false); |
320ae51f JA |
894 | } |
895 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
896 | ||
2f268556 CH |
897 | void blk_mq_start_hw_queues(struct request_queue *q) |
898 | { | |
899 | struct blk_mq_hw_ctx *hctx; | |
900 | int i; | |
901 | ||
902 | queue_for_each_hw_ctx(q, hctx, i) | |
903 | blk_mq_start_hw_queue(hctx); | |
904 | } | |
905 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
906 | ||
907 | ||
1b4a3258 | 908 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
909 | { |
910 | struct blk_mq_hw_ctx *hctx; | |
911 | int i; | |
912 | ||
913 | queue_for_each_hw_ctx(q, hctx, i) { | |
914 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
915 | continue; | |
916 | ||
917 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
1b4a3258 | 918 | blk_mq_run_hw_queue(hctx, async); |
320ae51f JA |
919 | } |
920 | } | |
921 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
922 | ||
70f4db63 | 923 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
924 | { |
925 | struct blk_mq_hw_ctx *hctx; | |
926 | ||
70f4db63 | 927 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 928 | |
320ae51f JA |
929 | __blk_mq_run_hw_queue(hctx); |
930 | } | |
931 | ||
70f4db63 CH |
932 | static void blk_mq_delay_work_fn(struct work_struct *work) |
933 | { | |
934 | struct blk_mq_hw_ctx *hctx; | |
935 | ||
936 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
937 | ||
938 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
939 | __blk_mq_run_hw_queue(hctx); | |
940 | } | |
941 | ||
942 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
943 | { | |
19c66e59 ML |
944 | if (unlikely(!blk_mq_hw_queue_mapped(hctx))) |
945 | return; | |
70f4db63 | 946 | |
b657d7e6 CH |
947 | kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx), |
948 | &hctx->delay_work, msecs_to_jiffies(msecs)); | |
70f4db63 CH |
949 | } |
950 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
951 | ||
320ae51f | 952 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
72a0a36e | 953 | struct request *rq, bool at_head) |
320ae51f JA |
954 | { |
955 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
956 | ||
01b983c9 JA |
957 | trace_block_rq_insert(hctx->queue, rq); |
958 | ||
72a0a36e CH |
959 | if (at_head) |
960 | list_add(&rq->queuelist, &ctx->rq_list); | |
961 | else | |
962 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
4bb659b1 | 963 | |
320ae51f | 964 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
965 | } |
966 | ||
eeabc850 CH |
967 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
968 | bool async) | |
320ae51f | 969 | { |
eeabc850 | 970 | struct request_queue *q = rq->q; |
320ae51f | 971 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
972 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
973 | ||
974 | current_ctx = blk_mq_get_ctx(q); | |
975 | if (!cpu_online(ctx->cpu)) | |
976 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 977 | |
320ae51f JA |
978 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
979 | ||
a57a178a CH |
980 | spin_lock(&ctx->lock); |
981 | __blk_mq_insert_request(hctx, rq, at_head); | |
982 | spin_unlock(&ctx->lock); | |
320ae51f | 983 | |
320ae51f JA |
984 | if (run_queue) |
985 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
986 | |
987 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
988 | } |
989 | ||
990 | static void blk_mq_insert_requests(struct request_queue *q, | |
991 | struct blk_mq_ctx *ctx, | |
992 | struct list_head *list, | |
993 | int depth, | |
994 | bool from_schedule) | |
995 | ||
996 | { | |
997 | struct blk_mq_hw_ctx *hctx; | |
998 | struct blk_mq_ctx *current_ctx; | |
999 | ||
1000 | trace_block_unplug(q, depth, !from_schedule); | |
1001 | ||
1002 | current_ctx = blk_mq_get_ctx(q); | |
1003 | ||
1004 | if (!cpu_online(ctx->cpu)) | |
1005 | ctx = current_ctx; | |
1006 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1007 | ||
1008 | /* | |
1009 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
1010 | * offline now | |
1011 | */ | |
1012 | spin_lock(&ctx->lock); | |
1013 | while (!list_empty(list)) { | |
1014 | struct request *rq; | |
1015 | ||
1016 | rq = list_first_entry(list, struct request, queuelist); | |
1017 | list_del_init(&rq->queuelist); | |
1018 | rq->mq_ctx = ctx; | |
72a0a36e | 1019 | __blk_mq_insert_request(hctx, rq, false); |
320ae51f JA |
1020 | } |
1021 | spin_unlock(&ctx->lock); | |
1022 | ||
320ae51f | 1023 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 1024 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
1025 | } |
1026 | ||
1027 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1028 | { | |
1029 | struct request *rqa = container_of(a, struct request, queuelist); | |
1030 | struct request *rqb = container_of(b, struct request, queuelist); | |
1031 | ||
1032 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1033 | (rqa->mq_ctx == rqb->mq_ctx && | |
1034 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1035 | } | |
1036 | ||
1037 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1038 | { | |
1039 | struct blk_mq_ctx *this_ctx; | |
1040 | struct request_queue *this_q; | |
1041 | struct request *rq; | |
1042 | LIST_HEAD(list); | |
1043 | LIST_HEAD(ctx_list); | |
1044 | unsigned int depth; | |
1045 | ||
1046 | list_splice_init(&plug->mq_list, &list); | |
1047 | ||
1048 | list_sort(NULL, &list, plug_ctx_cmp); | |
1049 | ||
1050 | this_q = NULL; | |
1051 | this_ctx = NULL; | |
1052 | depth = 0; | |
1053 | ||
1054 | while (!list_empty(&list)) { | |
1055 | rq = list_entry_rq(list.next); | |
1056 | list_del_init(&rq->queuelist); | |
1057 | BUG_ON(!rq->q); | |
1058 | if (rq->mq_ctx != this_ctx) { | |
1059 | if (this_ctx) { | |
1060 | blk_mq_insert_requests(this_q, this_ctx, | |
1061 | &ctx_list, depth, | |
1062 | from_schedule); | |
1063 | } | |
1064 | ||
1065 | this_ctx = rq->mq_ctx; | |
1066 | this_q = rq->q; | |
1067 | depth = 0; | |
1068 | } | |
1069 | ||
1070 | depth++; | |
1071 | list_add_tail(&rq->queuelist, &ctx_list); | |
1072 | } | |
1073 | ||
1074 | /* | |
1075 | * If 'this_ctx' is set, we know we have entries to complete | |
1076 | * on 'ctx_list'. Do those. | |
1077 | */ | |
1078 | if (this_ctx) { | |
1079 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1080 | from_schedule); | |
1081 | } | |
1082 | } | |
1083 | ||
1084 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1085 | { | |
1086 | init_request_from_bio(rq, bio); | |
4b570521 | 1087 | |
3ee32372 | 1088 | if (blk_do_io_stat(rq)) |
4b570521 | 1089 | blk_account_io_start(rq, 1); |
320ae51f JA |
1090 | } |
1091 | ||
274a5843 JA |
1092 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1093 | { | |
1094 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1095 | !blk_queue_nomerges(hctx->queue); | |
1096 | } | |
1097 | ||
07068d5b JA |
1098 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1099 | struct blk_mq_ctx *ctx, | |
1100 | struct request *rq, struct bio *bio) | |
320ae51f | 1101 | { |
274a5843 | 1102 | if (!hctx_allow_merges(hctx)) { |
07068d5b JA |
1103 | blk_mq_bio_to_request(rq, bio); |
1104 | spin_lock(&ctx->lock); | |
1105 | insert_rq: | |
1106 | __blk_mq_insert_request(hctx, rq, false); | |
1107 | spin_unlock(&ctx->lock); | |
1108 | return false; | |
1109 | } else { | |
274a5843 JA |
1110 | struct request_queue *q = hctx->queue; |
1111 | ||
07068d5b JA |
1112 | spin_lock(&ctx->lock); |
1113 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1114 | blk_mq_bio_to_request(rq, bio); | |
1115 | goto insert_rq; | |
1116 | } | |
320ae51f | 1117 | |
07068d5b JA |
1118 | spin_unlock(&ctx->lock); |
1119 | __blk_mq_free_request(hctx, ctx, rq); | |
1120 | return true; | |
14ec77f3 | 1121 | } |
07068d5b | 1122 | } |
14ec77f3 | 1123 | |
07068d5b JA |
1124 | struct blk_map_ctx { |
1125 | struct blk_mq_hw_ctx *hctx; | |
1126 | struct blk_mq_ctx *ctx; | |
1127 | }; | |
1128 | ||
1129 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1130 | struct bio *bio, | |
1131 | struct blk_map_ctx *data) | |
1132 | { | |
1133 | struct blk_mq_hw_ctx *hctx; | |
1134 | struct blk_mq_ctx *ctx; | |
1135 | struct request *rq; | |
1136 | int rw = bio_data_dir(bio); | |
cb96a42c | 1137 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1138 | |
07068d5b | 1139 | if (unlikely(blk_mq_queue_enter(q))) { |
320ae51f | 1140 | bio_endio(bio, -EIO); |
07068d5b | 1141 | return NULL; |
320ae51f JA |
1142 | } |
1143 | ||
1144 | ctx = blk_mq_get_ctx(q); | |
1145 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1146 | ||
07068d5b | 1147 | if (rw_is_sync(bio->bi_rw)) |
27fbf4e8 | 1148 | rw |= REQ_SYNC; |
07068d5b | 1149 | |
320ae51f | 1150 | trace_block_getrq(q, bio, rw); |
cb96a42c ML |
1151 | blk_mq_set_alloc_data(&alloc_data, q, GFP_ATOMIC, false, ctx, |
1152 | hctx); | |
1153 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
5dee8577 | 1154 | if (unlikely(!rq)) { |
793597a6 | 1155 | __blk_mq_run_hw_queue(hctx); |
320ae51f JA |
1156 | blk_mq_put_ctx(ctx); |
1157 | trace_block_sleeprq(q, bio, rw); | |
793597a6 CH |
1158 | |
1159 | ctx = blk_mq_get_ctx(q); | |
320ae51f | 1160 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
cb96a42c ML |
1161 | blk_mq_set_alloc_data(&alloc_data, q, |
1162 | __GFP_WAIT|GFP_ATOMIC, false, ctx, hctx); | |
1163 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
1164 | ctx = alloc_data.ctx; | |
1165 | hctx = alloc_data.hctx; | |
320ae51f JA |
1166 | } |
1167 | ||
1168 | hctx->queued++; | |
07068d5b JA |
1169 | data->hctx = hctx; |
1170 | data->ctx = ctx; | |
1171 | return rq; | |
1172 | } | |
1173 | ||
1174 | /* | |
1175 | * Multiple hardware queue variant. This will not use per-process plugs, | |
1176 | * but will attempt to bypass the hctx queueing if we can go straight to | |
1177 | * hardware for SYNC IO. | |
1178 | */ | |
1179 | static void blk_mq_make_request(struct request_queue *q, struct bio *bio) | |
1180 | { | |
1181 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1182 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1183 | struct blk_map_ctx data; | |
1184 | struct request *rq; | |
1185 | ||
1186 | blk_queue_bounce(q, &bio); | |
1187 | ||
1188 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1189 | bio_endio(bio, -EIO); | |
1190 | return; | |
1191 | } | |
1192 | ||
1193 | rq = blk_mq_map_request(q, bio, &data); | |
1194 | if (unlikely(!rq)) | |
1195 | return; | |
1196 | ||
1197 | if (unlikely(is_flush_fua)) { | |
1198 | blk_mq_bio_to_request(rq, bio); | |
1199 | blk_insert_flush(rq); | |
1200 | goto run_queue; | |
1201 | } | |
1202 | ||
e167dfb5 JA |
1203 | /* |
1204 | * If the driver supports defer issued based on 'last', then | |
1205 | * queue it up like normal since we can potentially save some | |
1206 | * CPU this way. | |
1207 | */ | |
1208 | if (is_sync && !(data.hctx->flags & BLK_MQ_F_DEFER_ISSUE)) { | |
74c45052 JA |
1209 | struct blk_mq_queue_data bd = { |
1210 | .rq = rq, | |
1211 | .list = NULL, | |
1212 | .last = 1 | |
1213 | }; | |
07068d5b JA |
1214 | int ret; |
1215 | ||
1216 | blk_mq_bio_to_request(rq, bio); | |
07068d5b JA |
1217 | |
1218 | /* | |
1219 | * For OK queue, we are done. For error, kill it. Any other | |
1220 | * error (busy), just add it to our list as we previously | |
1221 | * would have done | |
1222 | */ | |
74c45052 | 1223 | ret = q->mq_ops->queue_rq(data.hctx, &bd); |
07068d5b JA |
1224 | if (ret == BLK_MQ_RQ_QUEUE_OK) |
1225 | goto done; | |
1226 | else { | |
1227 | __blk_mq_requeue_request(rq); | |
1228 | ||
1229 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1230 | rq->errors = -EIO; | |
c8a446ad | 1231 | blk_mq_end_request(rq, rq->errors); |
07068d5b JA |
1232 | goto done; |
1233 | } | |
1234 | } | |
1235 | } | |
1236 | ||
1237 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { | |
1238 | /* | |
1239 | * For a SYNC request, send it to the hardware immediately. For | |
1240 | * an ASYNC request, just ensure that we run it later on. The | |
1241 | * latter allows for merging opportunities and more efficient | |
1242 | * dispatching. | |
1243 | */ | |
1244 | run_queue: | |
1245 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
1246 | } | |
1247 | done: | |
1248 | blk_mq_put_ctx(data.ctx); | |
1249 | } | |
1250 | ||
1251 | /* | |
1252 | * Single hardware queue variant. This will attempt to use any per-process | |
1253 | * plug for merging and IO deferral. | |
1254 | */ | |
1255 | static void blk_sq_make_request(struct request_queue *q, struct bio *bio) | |
1256 | { | |
1257 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1258 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1259 | unsigned int use_plug, request_count = 0; | |
1260 | struct blk_map_ctx data; | |
1261 | struct request *rq; | |
1262 | ||
1263 | /* | |
1264 | * If we have multiple hardware queues, just go directly to | |
1265 | * one of those for sync IO. | |
1266 | */ | |
1267 | use_plug = !is_flush_fua && !is_sync; | |
1268 | ||
1269 | blk_queue_bounce(q, &bio); | |
1270 | ||
1271 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1272 | bio_endio(bio, -EIO); | |
1273 | return; | |
1274 | } | |
1275 | ||
1276 | if (use_plug && !blk_queue_nomerges(q) && | |
1277 | blk_attempt_plug_merge(q, bio, &request_count)) | |
1278 | return; | |
1279 | ||
1280 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec JA |
1281 | if (unlikely(!rq)) |
1282 | return; | |
320ae51f JA |
1283 | |
1284 | if (unlikely(is_flush_fua)) { | |
1285 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1286 | blk_insert_flush(rq); |
1287 | goto run_queue; | |
1288 | } | |
1289 | ||
1290 | /* | |
1291 | * A task plug currently exists. Since this is completely lockless, | |
1292 | * utilize that to temporarily store requests until the task is | |
1293 | * either done or scheduled away. | |
1294 | */ | |
1295 | if (use_plug) { | |
1296 | struct blk_plug *plug = current->plug; | |
1297 | ||
1298 | if (plug) { | |
1299 | blk_mq_bio_to_request(rq, bio); | |
92f399c7 | 1300 | if (list_empty(&plug->mq_list)) |
320ae51f JA |
1301 | trace_block_plug(q); |
1302 | else if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
1303 | blk_flush_plug_list(plug, false); | |
1304 | trace_block_plug(q); | |
1305 | } | |
1306 | list_add_tail(&rq->queuelist, &plug->mq_list); | |
07068d5b | 1307 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1308 | return; |
1309 | } | |
1310 | } | |
1311 | ||
07068d5b JA |
1312 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1313 | /* | |
1314 | * For a SYNC request, send it to the hardware immediately. For | |
1315 | * an ASYNC request, just ensure that we run it later on. The | |
1316 | * latter allows for merging opportunities and more efficient | |
1317 | * dispatching. | |
1318 | */ | |
1319 | run_queue: | |
1320 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1321 | } |
1322 | ||
07068d5b | 1323 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1324 | } |
1325 | ||
1326 | /* | |
1327 | * Default mapping to a software queue, since we use one per CPU. | |
1328 | */ | |
1329 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1330 | { | |
1331 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1332 | } | |
1333 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1334 | ||
24d2f903 CH |
1335 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1336 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1337 | { |
e9b267d9 | 1338 | struct page *page; |
320ae51f | 1339 | |
24d2f903 | 1340 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1341 | int i; |
320ae51f | 1342 | |
24d2f903 CH |
1343 | for (i = 0; i < tags->nr_tags; i++) { |
1344 | if (!tags->rqs[i]) | |
e9b267d9 | 1345 | continue; |
24d2f903 CH |
1346 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1347 | hctx_idx, i); | |
a5164405 | 1348 | tags->rqs[i] = NULL; |
e9b267d9 | 1349 | } |
320ae51f | 1350 | } |
320ae51f | 1351 | |
24d2f903 CH |
1352 | while (!list_empty(&tags->page_list)) { |
1353 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1354 | list_del_init(&page->lru); |
320ae51f JA |
1355 | __free_pages(page, page->private); |
1356 | } | |
1357 | ||
24d2f903 | 1358 | kfree(tags->rqs); |
320ae51f | 1359 | |
24d2f903 | 1360 | blk_mq_free_tags(tags); |
320ae51f JA |
1361 | } |
1362 | ||
1363 | static size_t order_to_size(unsigned int order) | |
1364 | { | |
4ca08500 | 1365 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1366 | } |
1367 | ||
24d2f903 CH |
1368 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1369 | unsigned int hctx_idx) | |
320ae51f | 1370 | { |
24d2f903 | 1371 | struct blk_mq_tags *tags; |
320ae51f JA |
1372 | unsigned int i, j, entries_per_page, max_order = 4; |
1373 | size_t rq_size, left; | |
1374 | ||
24d2f903 CH |
1375 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
1376 | set->numa_node); | |
1377 | if (!tags) | |
1378 | return NULL; | |
320ae51f | 1379 | |
24d2f903 CH |
1380 | INIT_LIST_HEAD(&tags->page_list); |
1381 | ||
a5164405 JA |
1382 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1383 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1384 | set->numa_node); | |
24d2f903 CH |
1385 | if (!tags->rqs) { |
1386 | blk_mq_free_tags(tags); | |
1387 | return NULL; | |
1388 | } | |
320ae51f JA |
1389 | |
1390 | /* | |
1391 | * rq_size is the size of the request plus driver payload, rounded | |
1392 | * to the cacheline size | |
1393 | */ | |
24d2f903 | 1394 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1395 | cache_line_size()); |
24d2f903 | 1396 | left = rq_size * set->queue_depth; |
320ae51f | 1397 | |
24d2f903 | 1398 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1399 | int this_order = max_order; |
1400 | struct page *page; | |
1401 | int to_do; | |
1402 | void *p; | |
1403 | ||
1404 | while (left < order_to_size(this_order - 1) && this_order) | |
1405 | this_order--; | |
1406 | ||
1407 | do { | |
a5164405 JA |
1408 | page = alloc_pages_node(set->numa_node, |
1409 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1410 | this_order); | |
320ae51f JA |
1411 | if (page) |
1412 | break; | |
1413 | if (!this_order--) | |
1414 | break; | |
1415 | if (order_to_size(this_order) < rq_size) | |
1416 | break; | |
1417 | } while (1); | |
1418 | ||
1419 | if (!page) | |
24d2f903 | 1420 | goto fail; |
320ae51f JA |
1421 | |
1422 | page->private = this_order; | |
24d2f903 | 1423 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1424 | |
1425 | p = page_address(page); | |
1426 | entries_per_page = order_to_size(this_order) / rq_size; | |
24d2f903 | 1427 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1428 | left -= to_do * rq_size; |
1429 | for (j = 0; j < to_do; j++) { | |
24d2f903 | 1430 | tags->rqs[i] = p; |
683d0e12 DH |
1431 | tags->rqs[i]->atomic_flags = 0; |
1432 | tags->rqs[i]->cmd_flags = 0; | |
24d2f903 CH |
1433 | if (set->ops->init_request) { |
1434 | if (set->ops->init_request(set->driver_data, | |
1435 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1436 | set->numa_node)) { |
1437 | tags->rqs[i] = NULL; | |
24d2f903 | 1438 | goto fail; |
a5164405 | 1439 | } |
e9b267d9 CH |
1440 | } |
1441 | ||
320ae51f JA |
1442 | p += rq_size; |
1443 | i++; | |
1444 | } | |
1445 | } | |
1446 | ||
24d2f903 | 1447 | return tags; |
320ae51f | 1448 | |
24d2f903 | 1449 | fail: |
24d2f903 CH |
1450 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1451 | return NULL; | |
320ae51f JA |
1452 | } |
1453 | ||
1429d7c9 JA |
1454 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1455 | { | |
1456 | kfree(bitmap->map); | |
1457 | } | |
1458 | ||
1459 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1460 | { | |
1461 | unsigned int bpw = 8, total, num_maps, i; | |
1462 | ||
1463 | bitmap->bits_per_word = bpw; | |
1464 | ||
1465 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1466 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1467 | GFP_KERNEL, node); | |
1468 | if (!bitmap->map) | |
1469 | return -ENOMEM; | |
1470 | ||
1471 | bitmap->map_size = num_maps; | |
1472 | ||
1473 | total = nr_cpu_ids; | |
1474 | for (i = 0; i < num_maps; i++) { | |
1475 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1476 | total -= bitmap->map[i].depth; | |
1477 | } | |
1478 | ||
1479 | return 0; | |
1480 | } | |
1481 | ||
484b4061 JA |
1482 | static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) |
1483 | { | |
1484 | struct request_queue *q = hctx->queue; | |
1485 | struct blk_mq_ctx *ctx; | |
1486 | LIST_HEAD(tmp); | |
1487 | ||
1488 | /* | |
1489 | * Move ctx entries to new CPU, if this one is going away. | |
1490 | */ | |
1491 | ctx = __blk_mq_get_ctx(q, cpu); | |
1492 | ||
1493 | spin_lock(&ctx->lock); | |
1494 | if (!list_empty(&ctx->rq_list)) { | |
1495 | list_splice_init(&ctx->rq_list, &tmp); | |
1496 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1497 | } | |
1498 | spin_unlock(&ctx->lock); | |
1499 | ||
1500 | if (list_empty(&tmp)) | |
1501 | return NOTIFY_OK; | |
1502 | ||
1503 | ctx = blk_mq_get_ctx(q); | |
1504 | spin_lock(&ctx->lock); | |
1505 | ||
1506 | while (!list_empty(&tmp)) { | |
1507 | struct request *rq; | |
1508 | ||
1509 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1510 | rq->mq_ctx = ctx; | |
1511 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1512 | } | |
1513 | ||
1514 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1515 | blk_mq_hctx_mark_pending(hctx, ctx); | |
1516 | ||
1517 | spin_unlock(&ctx->lock); | |
1518 | ||
1519 | blk_mq_run_hw_queue(hctx, true); | |
1520 | blk_mq_put_ctx(ctx); | |
1521 | return NOTIFY_OK; | |
1522 | } | |
1523 | ||
1524 | static int blk_mq_hctx_cpu_online(struct blk_mq_hw_ctx *hctx, int cpu) | |
1525 | { | |
1526 | struct request_queue *q = hctx->queue; | |
1527 | struct blk_mq_tag_set *set = q->tag_set; | |
1528 | ||
1529 | if (set->tags[hctx->queue_num]) | |
1530 | return NOTIFY_OK; | |
1531 | ||
1532 | set->tags[hctx->queue_num] = blk_mq_init_rq_map(set, hctx->queue_num); | |
1533 | if (!set->tags[hctx->queue_num]) | |
1534 | return NOTIFY_STOP; | |
1535 | ||
1536 | hctx->tags = set->tags[hctx->queue_num]; | |
1537 | return NOTIFY_OK; | |
1538 | } | |
1539 | ||
1540 | static int blk_mq_hctx_notify(void *data, unsigned long action, | |
1541 | unsigned int cpu) | |
1542 | { | |
1543 | struct blk_mq_hw_ctx *hctx = data; | |
1544 | ||
1545 | if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) | |
1546 | return blk_mq_hctx_cpu_offline(hctx, cpu); | |
1547 | else if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) | |
1548 | return blk_mq_hctx_cpu_online(hctx, cpu); | |
1549 | ||
1550 | return NOTIFY_OK; | |
1551 | } | |
1552 | ||
08e98fc6 ML |
1553 | static void blk_mq_exit_hctx(struct request_queue *q, |
1554 | struct blk_mq_tag_set *set, | |
1555 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
1556 | { | |
f70ced09 ML |
1557 | unsigned flush_start_tag = set->queue_depth; |
1558 | ||
08e98fc6 ML |
1559 | blk_mq_tag_idle(hctx); |
1560 | ||
f70ced09 ML |
1561 | if (set->ops->exit_request) |
1562 | set->ops->exit_request(set->driver_data, | |
1563 | hctx->fq->flush_rq, hctx_idx, | |
1564 | flush_start_tag + hctx_idx); | |
1565 | ||
08e98fc6 ML |
1566 | if (set->ops->exit_hctx) |
1567 | set->ops->exit_hctx(hctx, hctx_idx); | |
1568 | ||
1569 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
f70ced09 | 1570 | blk_free_flush_queue(hctx->fq); |
08e98fc6 ML |
1571 | kfree(hctx->ctxs); |
1572 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1573 | } | |
1574 | ||
624dbe47 ML |
1575 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1576 | struct blk_mq_tag_set *set, int nr_queue) | |
1577 | { | |
1578 | struct blk_mq_hw_ctx *hctx; | |
1579 | unsigned int i; | |
1580 | ||
1581 | queue_for_each_hw_ctx(q, hctx, i) { | |
1582 | if (i == nr_queue) | |
1583 | break; | |
08e98fc6 | 1584 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 1585 | } |
624dbe47 ML |
1586 | } |
1587 | ||
1588 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1589 | struct blk_mq_tag_set *set) | |
1590 | { | |
1591 | struct blk_mq_hw_ctx *hctx; | |
1592 | unsigned int i; | |
1593 | ||
1594 | queue_for_each_hw_ctx(q, hctx, i) { | |
1595 | free_cpumask_var(hctx->cpumask); | |
cdef54dd | 1596 | kfree(hctx); |
624dbe47 ML |
1597 | } |
1598 | } | |
1599 | ||
08e98fc6 ML |
1600 | static int blk_mq_init_hctx(struct request_queue *q, |
1601 | struct blk_mq_tag_set *set, | |
1602 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 1603 | { |
08e98fc6 | 1604 | int node; |
f70ced09 | 1605 | unsigned flush_start_tag = set->queue_depth; |
08e98fc6 ML |
1606 | |
1607 | node = hctx->numa_node; | |
1608 | if (node == NUMA_NO_NODE) | |
1609 | node = hctx->numa_node = set->numa_node; | |
1610 | ||
1611 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); | |
1612 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
1613 | spin_lock_init(&hctx->lock); | |
1614 | INIT_LIST_HEAD(&hctx->dispatch); | |
1615 | hctx->queue = q; | |
1616 | hctx->queue_num = hctx_idx; | |
1617 | hctx->flags = set->flags; | |
1618 | hctx->cmd_size = set->cmd_size; | |
1619 | ||
1620 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1621 | blk_mq_hctx_notify, hctx); | |
1622 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1623 | ||
1624 | hctx->tags = set->tags[hctx_idx]; | |
320ae51f JA |
1625 | |
1626 | /* | |
08e98fc6 ML |
1627 | * Allocate space for all possible cpus to avoid allocation at |
1628 | * runtime | |
320ae51f | 1629 | */ |
08e98fc6 ML |
1630 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), |
1631 | GFP_KERNEL, node); | |
1632 | if (!hctx->ctxs) | |
1633 | goto unregister_cpu_notifier; | |
320ae51f | 1634 | |
08e98fc6 ML |
1635 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
1636 | goto free_ctxs; | |
320ae51f | 1637 | |
08e98fc6 | 1638 | hctx->nr_ctx = 0; |
320ae51f | 1639 | |
08e98fc6 ML |
1640 | if (set->ops->init_hctx && |
1641 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
1642 | goto free_bitmap; | |
320ae51f | 1643 | |
f70ced09 ML |
1644 | hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); |
1645 | if (!hctx->fq) | |
1646 | goto exit_hctx; | |
320ae51f | 1647 | |
f70ced09 ML |
1648 | if (set->ops->init_request && |
1649 | set->ops->init_request(set->driver_data, | |
1650 | hctx->fq->flush_rq, hctx_idx, | |
1651 | flush_start_tag + hctx_idx, node)) | |
1652 | goto free_fq; | |
320ae51f | 1653 | |
08e98fc6 | 1654 | return 0; |
320ae51f | 1655 | |
f70ced09 ML |
1656 | free_fq: |
1657 | kfree(hctx->fq); | |
1658 | exit_hctx: | |
1659 | if (set->ops->exit_hctx) | |
1660 | set->ops->exit_hctx(hctx, hctx_idx); | |
08e98fc6 ML |
1661 | free_bitmap: |
1662 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1663 | free_ctxs: | |
1664 | kfree(hctx->ctxs); | |
1665 | unregister_cpu_notifier: | |
1666 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
320ae51f | 1667 | |
08e98fc6 ML |
1668 | return -1; |
1669 | } | |
320ae51f | 1670 | |
08e98fc6 ML |
1671 | static int blk_mq_init_hw_queues(struct request_queue *q, |
1672 | struct blk_mq_tag_set *set) | |
1673 | { | |
1674 | struct blk_mq_hw_ctx *hctx; | |
1675 | unsigned int i; | |
320ae51f | 1676 | |
08e98fc6 ML |
1677 | /* |
1678 | * Initialize hardware queues | |
1679 | */ | |
1680 | queue_for_each_hw_ctx(q, hctx, i) { | |
1681 | if (blk_mq_init_hctx(q, set, hctx, i)) | |
320ae51f JA |
1682 | break; |
1683 | } | |
1684 | ||
1685 | if (i == q->nr_hw_queues) | |
1686 | return 0; | |
1687 | ||
1688 | /* | |
1689 | * Init failed | |
1690 | */ | |
624dbe47 | 1691 | blk_mq_exit_hw_queues(q, set, i); |
320ae51f JA |
1692 | |
1693 | return 1; | |
1694 | } | |
1695 | ||
1696 | static void blk_mq_init_cpu_queues(struct request_queue *q, | |
1697 | unsigned int nr_hw_queues) | |
1698 | { | |
1699 | unsigned int i; | |
1700 | ||
1701 | for_each_possible_cpu(i) { | |
1702 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1703 | struct blk_mq_hw_ctx *hctx; | |
1704 | ||
1705 | memset(__ctx, 0, sizeof(*__ctx)); | |
1706 | __ctx->cpu = i; | |
1707 | spin_lock_init(&__ctx->lock); | |
1708 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1709 | __ctx->queue = q; | |
1710 | ||
1711 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1712 | if (!cpu_online(i)) |
1713 | continue; | |
1714 | ||
e4043dcf JA |
1715 | hctx = q->mq_ops->map_queue(q, i); |
1716 | cpumask_set_cpu(i, hctx->cpumask); | |
1717 | hctx->nr_ctx++; | |
1718 | ||
320ae51f JA |
1719 | /* |
1720 | * Set local node, IFF we have more than one hw queue. If | |
1721 | * not, we remain on the home node of the device | |
1722 | */ | |
1723 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
1724 | hctx->numa_node = cpu_to_node(i); | |
1725 | } | |
1726 | } | |
1727 | ||
1728 | static void blk_mq_map_swqueue(struct request_queue *q) | |
1729 | { | |
1730 | unsigned int i; | |
1731 | struct blk_mq_hw_ctx *hctx; | |
1732 | struct blk_mq_ctx *ctx; | |
1733 | ||
1734 | queue_for_each_hw_ctx(q, hctx, i) { | |
e4043dcf | 1735 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1736 | hctx->nr_ctx = 0; |
1737 | } | |
1738 | ||
1739 | /* | |
1740 | * Map software to hardware queues | |
1741 | */ | |
1742 | queue_for_each_ctx(q, ctx, i) { | |
1743 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
e4043dcf JA |
1744 | if (!cpu_online(i)) |
1745 | continue; | |
1746 | ||
320ae51f | 1747 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1748 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1749 | ctx->index_hw = hctx->nr_ctx; |
1750 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1751 | } | |
506e931f JA |
1752 | |
1753 | queue_for_each_hw_ctx(q, hctx, i) { | |
484b4061 | 1754 | /* |
a68aafa5 JA |
1755 | * If no software queues are mapped to this hardware queue, |
1756 | * disable it and free the request entries. | |
484b4061 JA |
1757 | */ |
1758 | if (!hctx->nr_ctx) { | |
1759 | struct blk_mq_tag_set *set = q->tag_set; | |
1760 | ||
1761 | if (set->tags[i]) { | |
1762 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1763 | set->tags[i] = NULL; | |
1764 | hctx->tags = NULL; | |
1765 | } | |
1766 | continue; | |
1767 | } | |
1768 | ||
1769 | /* | |
1770 | * Initialize batch roundrobin counts | |
1771 | */ | |
506e931f JA |
1772 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1773 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1774 | } | |
320ae51f JA |
1775 | } |
1776 | ||
0d2602ca JA |
1777 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |
1778 | { | |
1779 | struct blk_mq_hw_ctx *hctx; | |
1780 | struct request_queue *q; | |
1781 | bool shared; | |
1782 | int i; | |
1783 | ||
1784 | if (set->tag_list.next == set->tag_list.prev) | |
1785 | shared = false; | |
1786 | else | |
1787 | shared = true; | |
1788 | ||
1789 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1790 | blk_mq_freeze_queue(q); | |
1791 | ||
1792 | queue_for_each_hw_ctx(q, hctx, i) { | |
1793 | if (shared) | |
1794 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1795 | else | |
1796 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1797 | } | |
1798 | blk_mq_unfreeze_queue(q); | |
1799 | } | |
1800 | } | |
1801 | ||
1802 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1803 | { | |
1804 | struct blk_mq_tag_set *set = q->tag_set; | |
1805 | ||
0d2602ca JA |
1806 | mutex_lock(&set->tag_list_lock); |
1807 | list_del_init(&q->tag_set_list); | |
1808 | blk_mq_update_tag_set_depth(set); | |
1809 | mutex_unlock(&set->tag_list_lock); | |
0d2602ca JA |
1810 | } |
1811 | ||
1812 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1813 | struct request_queue *q) | |
1814 | { | |
1815 | q->tag_set = set; | |
1816 | ||
1817 | mutex_lock(&set->tag_list_lock); | |
1818 | list_add_tail(&q->tag_set_list, &set->tag_list); | |
1819 | blk_mq_update_tag_set_depth(set); | |
1820 | mutex_unlock(&set->tag_list_lock); | |
1821 | } | |
1822 | ||
24d2f903 | 1823 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
320ae51f JA |
1824 | { |
1825 | struct blk_mq_hw_ctx **hctxs; | |
e6cdb092 | 1826 | struct blk_mq_ctx __percpu *ctx; |
320ae51f | 1827 | struct request_queue *q; |
f14bbe77 | 1828 | unsigned int *map; |
320ae51f JA |
1829 | int i; |
1830 | ||
320ae51f JA |
1831 | ctx = alloc_percpu(struct blk_mq_ctx); |
1832 | if (!ctx) | |
1833 | return ERR_PTR(-ENOMEM); | |
1834 | ||
24d2f903 CH |
1835 | hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, |
1836 | set->numa_node); | |
320ae51f JA |
1837 | |
1838 | if (!hctxs) | |
1839 | goto err_percpu; | |
1840 | ||
f14bbe77 JA |
1841 | map = blk_mq_make_queue_map(set); |
1842 | if (!map) | |
1843 | goto err_map; | |
1844 | ||
24d2f903 | 1845 | for (i = 0; i < set->nr_hw_queues; i++) { |
f14bbe77 JA |
1846 | int node = blk_mq_hw_queue_to_node(map, i); |
1847 | ||
cdef54dd CH |
1848 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1849 | GFP_KERNEL, node); | |
320ae51f JA |
1850 | if (!hctxs[i]) |
1851 | goto err_hctxs; | |
1852 | ||
a86073e4 JA |
1853 | if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, |
1854 | node)) | |
e4043dcf JA |
1855 | goto err_hctxs; |
1856 | ||
0d2602ca | 1857 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1858 | hctxs[i]->numa_node = node; |
320ae51f JA |
1859 | hctxs[i]->queue_num = i; |
1860 | } | |
1861 | ||
24d2f903 | 1862 | q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); |
320ae51f JA |
1863 | if (!q) |
1864 | goto err_hctxs; | |
1865 | ||
17497acb TH |
1866 | /* |
1867 | * Init percpu_ref in atomic mode so that it's faster to shutdown. | |
1868 | * See blk_register_queue() for details. | |
1869 | */ | |
a34375ef | 1870 | if (percpu_ref_init(&q->mq_usage_counter, blk_mq_usage_counter_release, |
17497acb | 1871 | PERCPU_REF_INIT_ATOMIC, GFP_KERNEL)) |
3d2936f4 ML |
1872 | goto err_map; |
1873 | ||
320ae51f JA |
1874 | setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); |
1875 | blk_queue_rq_timeout(q, 30000); | |
1876 | ||
1877 | q->nr_queues = nr_cpu_ids; | |
24d2f903 | 1878 | q->nr_hw_queues = set->nr_hw_queues; |
f14bbe77 | 1879 | q->mq_map = map; |
320ae51f JA |
1880 | |
1881 | q->queue_ctx = ctx; | |
1882 | q->queue_hw_ctx = hctxs; | |
1883 | ||
24d2f903 | 1884 | q->mq_ops = set->ops; |
94eddfbe | 1885 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 1886 | |
05f1dd53 JA |
1887 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
1888 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
1889 | ||
1be036e9 CH |
1890 | q->sg_reserved_size = INT_MAX; |
1891 | ||
6fca6a61 CH |
1892 | INIT_WORK(&q->requeue_work, blk_mq_requeue_work); |
1893 | INIT_LIST_HEAD(&q->requeue_list); | |
1894 | spin_lock_init(&q->requeue_lock); | |
1895 | ||
07068d5b JA |
1896 | if (q->nr_hw_queues > 1) |
1897 | blk_queue_make_request(q, blk_mq_make_request); | |
1898 | else | |
1899 | blk_queue_make_request(q, blk_sq_make_request); | |
1900 | ||
24d2f903 CH |
1901 | if (set->timeout) |
1902 | blk_queue_rq_timeout(q, set->timeout); | |
320ae51f | 1903 | |
eba71768 JA |
1904 | /* |
1905 | * Do this after blk_queue_make_request() overrides it... | |
1906 | */ | |
1907 | q->nr_requests = set->queue_depth; | |
1908 | ||
24d2f903 CH |
1909 | if (set->ops->complete) |
1910 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 1911 | |
24d2f903 | 1912 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 1913 | |
24d2f903 | 1914 | if (blk_mq_init_hw_queues(q, set)) |
1bcb1ead | 1915 | goto err_hw; |
18741986 | 1916 | |
320ae51f JA |
1917 | mutex_lock(&all_q_mutex); |
1918 | list_add_tail(&q->all_q_node, &all_q_list); | |
1919 | mutex_unlock(&all_q_mutex); | |
1920 | ||
0d2602ca JA |
1921 | blk_mq_add_queue_tag_set(set, q); |
1922 | ||
484b4061 JA |
1923 | blk_mq_map_swqueue(q); |
1924 | ||
320ae51f | 1925 | return q; |
18741986 | 1926 | |
320ae51f | 1927 | err_hw: |
320ae51f JA |
1928 | blk_cleanup_queue(q); |
1929 | err_hctxs: | |
f14bbe77 | 1930 | kfree(map); |
24d2f903 | 1931 | for (i = 0; i < set->nr_hw_queues; i++) { |
320ae51f JA |
1932 | if (!hctxs[i]) |
1933 | break; | |
e4043dcf | 1934 | free_cpumask_var(hctxs[i]->cpumask); |
cdef54dd | 1935 | kfree(hctxs[i]); |
320ae51f | 1936 | } |
f14bbe77 | 1937 | err_map: |
320ae51f JA |
1938 | kfree(hctxs); |
1939 | err_percpu: | |
1940 | free_percpu(ctx); | |
1941 | return ERR_PTR(-ENOMEM); | |
1942 | } | |
1943 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1944 | ||
1945 | void blk_mq_free_queue(struct request_queue *q) | |
1946 | { | |
624dbe47 | 1947 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 1948 | |
0d2602ca JA |
1949 | blk_mq_del_queue_tag_set(q); |
1950 | ||
624dbe47 ML |
1951 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
1952 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 1953 | |
add703fd | 1954 | percpu_ref_exit(&q->mq_usage_counter); |
3d2936f4 | 1955 | |
320ae51f JA |
1956 | free_percpu(q->queue_ctx); |
1957 | kfree(q->queue_hw_ctx); | |
1958 | kfree(q->mq_map); | |
1959 | ||
1960 | q->queue_ctx = NULL; | |
1961 | q->queue_hw_ctx = NULL; | |
1962 | q->mq_map = NULL; | |
1963 | ||
1964 | mutex_lock(&all_q_mutex); | |
1965 | list_del_init(&q->all_q_node); | |
1966 | mutex_unlock(&all_q_mutex); | |
1967 | } | |
320ae51f JA |
1968 | |
1969 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
f618ef7c | 1970 | static void blk_mq_queue_reinit(struct request_queue *q) |
320ae51f | 1971 | { |
f3af020b | 1972 | WARN_ON_ONCE(!q->mq_freeze_depth); |
320ae51f | 1973 | |
67aec14c JA |
1974 | blk_mq_sysfs_unregister(q); |
1975 | ||
320ae51f JA |
1976 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues); |
1977 | ||
1978 | /* | |
1979 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
1980 | * we should change hctx numa_node according to new topology (this | |
1981 | * involves free and re-allocate memory, worthy doing?) | |
1982 | */ | |
1983 | ||
1984 | blk_mq_map_swqueue(q); | |
1985 | ||
67aec14c | 1986 | blk_mq_sysfs_register(q); |
320ae51f JA |
1987 | } |
1988 | ||
f618ef7c PG |
1989 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
1990 | unsigned long action, void *hcpu) | |
320ae51f JA |
1991 | { |
1992 | struct request_queue *q; | |
1993 | ||
1994 | /* | |
9fccfed8 JA |
1995 | * Before new mappings are established, hotadded cpu might already |
1996 | * start handling requests. This doesn't break anything as we map | |
1997 | * offline CPUs to first hardware queue. We will re-init the queue | |
1998 | * below to get optimal settings. | |
320ae51f JA |
1999 | */ |
2000 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN && | |
2001 | action != CPU_ONLINE && action != CPU_ONLINE_FROZEN) | |
2002 | return NOTIFY_OK; | |
2003 | ||
2004 | mutex_lock(&all_q_mutex); | |
f3af020b TH |
2005 | |
2006 | /* | |
2007 | * We need to freeze and reinit all existing queues. Freezing | |
2008 | * involves synchronous wait for an RCU grace period and doing it | |
2009 | * one by one may take a long time. Start freezing all queues in | |
2010 | * one swoop and then wait for the completions so that freezing can | |
2011 | * take place in parallel. | |
2012 | */ | |
2013 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2014 | blk_mq_freeze_queue_start(q); | |
2015 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2016 | blk_mq_freeze_queue_wait(q); | |
2017 | ||
320ae51f JA |
2018 | list_for_each_entry(q, &all_q_list, all_q_node) |
2019 | blk_mq_queue_reinit(q); | |
f3af020b TH |
2020 | |
2021 | list_for_each_entry(q, &all_q_list, all_q_node) | |
2022 | blk_mq_unfreeze_queue(q); | |
2023 | ||
320ae51f JA |
2024 | mutex_unlock(&all_q_mutex); |
2025 | return NOTIFY_OK; | |
2026 | } | |
2027 | ||
a5164405 JA |
2028 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
2029 | { | |
2030 | int i; | |
2031 | ||
2032 | for (i = 0; i < set->nr_hw_queues; i++) { | |
2033 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
2034 | if (!set->tags[i]) | |
2035 | goto out_unwind; | |
2036 | } | |
2037 | ||
2038 | return 0; | |
2039 | ||
2040 | out_unwind: | |
2041 | while (--i >= 0) | |
2042 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2043 | ||
a5164405 JA |
2044 | return -ENOMEM; |
2045 | } | |
2046 | ||
2047 | /* | |
2048 | * Allocate the request maps associated with this tag_set. Note that this | |
2049 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
2050 | * will be updated to reflect the allocated depth. | |
2051 | */ | |
2052 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
2053 | { | |
2054 | unsigned int depth; | |
2055 | int err; | |
2056 | ||
2057 | depth = set->queue_depth; | |
2058 | do { | |
2059 | err = __blk_mq_alloc_rq_maps(set); | |
2060 | if (!err) | |
2061 | break; | |
2062 | ||
2063 | set->queue_depth >>= 1; | |
2064 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
2065 | err = -ENOMEM; | |
2066 | break; | |
2067 | } | |
2068 | } while (set->queue_depth); | |
2069 | ||
2070 | if (!set->queue_depth || err) { | |
2071 | pr_err("blk-mq: failed to allocate request map\n"); | |
2072 | return -ENOMEM; | |
2073 | } | |
2074 | ||
2075 | if (depth != set->queue_depth) | |
2076 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2077 | depth, set->queue_depth); | |
2078 | ||
2079 | return 0; | |
2080 | } | |
2081 | ||
a4391c64 JA |
2082 | /* |
2083 | * Alloc a tag set to be associated with one or more request queues. | |
2084 | * May fail with EINVAL for various error conditions. May adjust the | |
2085 | * requested depth down, if if it too large. In that case, the set | |
2086 | * value will be stored in set->queue_depth. | |
2087 | */ | |
24d2f903 CH |
2088 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2089 | { | |
205fb5f5 BVA |
2090 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
2091 | ||
24d2f903 CH |
2092 | if (!set->nr_hw_queues) |
2093 | return -EINVAL; | |
a4391c64 | 2094 | if (!set->queue_depth) |
24d2f903 CH |
2095 | return -EINVAL; |
2096 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2097 | return -EINVAL; | |
2098 | ||
cdef54dd | 2099 | if (!set->nr_hw_queues || !set->ops->queue_rq || !set->ops->map_queue) |
24d2f903 CH |
2100 | return -EINVAL; |
2101 | ||
a4391c64 JA |
2102 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2103 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2104 | BLK_MQ_MAX_DEPTH); | |
2105 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2106 | } | |
24d2f903 | 2107 | |
6637fadf SL |
2108 | /* |
2109 | * If a crashdump is active, then we are potentially in a very | |
2110 | * memory constrained environment. Limit us to 1 queue and | |
2111 | * 64 tags to prevent using too much memory. | |
2112 | */ | |
2113 | if (is_kdump_kernel()) { | |
2114 | set->nr_hw_queues = 1; | |
2115 | set->queue_depth = min(64U, set->queue_depth); | |
2116 | } | |
2117 | ||
48479005 ML |
2118 | set->tags = kmalloc_node(set->nr_hw_queues * |
2119 | sizeof(struct blk_mq_tags *), | |
24d2f903 CH |
2120 | GFP_KERNEL, set->numa_node); |
2121 | if (!set->tags) | |
a5164405 | 2122 | return -ENOMEM; |
24d2f903 | 2123 | |
a5164405 JA |
2124 | if (blk_mq_alloc_rq_maps(set)) |
2125 | goto enomem; | |
24d2f903 | 2126 | |
0d2602ca JA |
2127 | mutex_init(&set->tag_list_lock); |
2128 | INIT_LIST_HEAD(&set->tag_list); | |
2129 | ||
24d2f903 | 2130 | return 0; |
a5164405 | 2131 | enomem: |
5676e7b6 RE |
2132 | kfree(set->tags); |
2133 | set->tags = NULL; | |
24d2f903 CH |
2134 | return -ENOMEM; |
2135 | } | |
2136 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2137 | ||
2138 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2139 | { | |
2140 | int i; | |
2141 | ||
484b4061 JA |
2142 | for (i = 0; i < set->nr_hw_queues; i++) { |
2143 | if (set->tags[i]) | |
2144 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2145 | } | |
2146 | ||
981bd189 | 2147 | kfree(set->tags); |
5676e7b6 | 2148 | set->tags = NULL; |
24d2f903 CH |
2149 | } |
2150 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2151 | ||
e3a2b3f9 JA |
2152 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2153 | { | |
2154 | struct blk_mq_tag_set *set = q->tag_set; | |
2155 | struct blk_mq_hw_ctx *hctx; | |
2156 | int i, ret; | |
2157 | ||
2158 | if (!set || nr > set->queue_depth) | |
2159 | return -EINVAL; | |
2160 | ||
2161 | ret = 0; | |
2162 | queue_for_each_hw_ctx(q, hctx, i) { | |
2163 | ret = blk_mq_tag_update_depth(hctx->tags, nr); | |
2164 | if (ret) | |
2165 | break; | |
2166 | } | |
2167 | ||
2168 | if (!ret) | |
2169 | q->nr_requests = nr; | |
2170 | ||
2171 | return ret; | |
2172 | } | |
2173 | ||
676141e4 JA |
2174 | void blk_mq_disable_hotplug(void) |
2175 | { | |
2176 | mutex_lock(&all_q_mutex); | |
2177 | } | |
2178 | ||
2179 | void blk_mq_enable_hotplug(void) | |
2180 | { | |
2181 | mutex_unlock(&all_q_mutex); | |
2182 | } | |
2183 | ||
320ae51f JA |
2184 | static int __init blk_mq_init(void) |
2185 | { | |
320ae51f JA |
2186 | blk_mq_cpu_init(); |
2187 | ||
add703fd | 2188 | hotcpu_notifier(blk_mq_queue_reinit_notify, 0); |
320ae51f JA |
2189 | |
2190 | return 0; | |
2191 | } | |
2192 | subsys_initcall(blk_mq_init); |