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Commit | Line | Data |
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75bb4625 JA |
1 | /* |
2 | * Block multiqueue core code | |
3 | * | |
4 | * Copyright (C) 2013-2014 Jens Axboe | |
5 | * Copyright (C) 2013-2014 Christoph Hellwig | |
6 | */ | |
320ae51f JA |
7 | #include <linux/kernel.h> |
8 | #include <linux/module.h> | |
9 | #include <linux/backing-dev.h> | |
10 | #include <linux/bio.h> | |
11 | #include <linux/blkdev.h> | |
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 | ||
f3af020b | 110 | static 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 TH |
122 | } |
123 | ||
124 | static void blk_mq_freeze_queue_wait(struct request_queue *q) | |
125 | { | |
add703fd | 126 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); |
43a5e4e2 ML |
127 | } |
128 | ||
f3af020b TH |
129 | /* |
130 | * Guarantee no request is in use, so we can change any data structure of | |
131 | * the queue afterward. | |
132 | */ | |
133 | void blk_mq_freeze_queue(struct request_queue *q) | |
134 | { | |
135 | blk_mq_freeze_queue_start(q); | |
136 | blk_mq_freeze_queue_wait(q); | |
137 | } | |
138 | ||
320ae51f JA |
139 | static void blk_mq_unfreeze_queue(struct request_queue *q) |
140 | { | |
cddd5d17 | 141 | bool wake; |
320ae51f JA |
142 | |
143 | spin_lock_irq(q->queue_lock); | |
780db207 TH |
144 | wake = !--q->mq_freeze_depth; |
145 | WARN_ON_ONCE(q->mq_freeze_depth < 0); | |
320ae51f | 146 | spin_unlock_irq(q->queue_lock); |
add703fd TH |
147 | if (wake) { |
148 | percpu_ref_reinit(&q->mq_usage_counter); | |
320ae51f | 149 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 150 | } |
320ae51f JA |
151 | } |
152 | ||
153 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) | |
154 | { | |
155 | return blk_mq_has_free_tags(hctx->tags); | |
156 | } | |
157 | EXPORT_SYMBOL(blk_mq_can_queue); | |
158 | ||
94eddfbe JA |
159 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
160 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 161 | { |
94eddfbe JA |
162 | if (blk_queue_io_stat(q)) |
163 | rw_flags |= REQ_IO_STAT; | |
164 | ||
af76e555 CH |
165 | INIT_LIST_HEAD(&rq->queuelist); |
166 | /* csd/requeue_work/fifo_time is initialized before use */ | |
167 | rq->q = q; | |
320ae51f | 168 | rq->mq_ctx = ctx; |
0d2602ca | 169 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
170 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
171 | rq->cpu = -1; | |
af76e555 CH |
172 | INIT_HLIST_NODE(&rq->hash); |
173 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
174 | rq->rq_disk = NULL; |
175 | rq->part = NULL; | |
3ee32372 | 176 | rq->start_time = jiffies; |
af76e555 CH |
177 | #ifdef CONFIG_BLK_CGROUP |
178 | rq->rl = NULL; | |
0fec08b4 | 179 | set_start_time_ns(rq); |
af76e555 CH |
180 | rq->io_start_time_ns = 0; |
181 | #endif | |
182 | rq->nr_phys_segments = 0; | |
183 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
184 | rq->nr_integrity_segments = 0; | |
185 | #endif | |
af76e555 CH |
186 | rq->special = NULL; |
187 | /* tag was already set */ | |
188 | rq->errors = 0; | |
af76e555 | 189 | |
6f4a1626 TB |
190 | rq->cmd = rq->__cmd; |
191 | ||
af76e555 CH |
192 | rq->extra_len = 0; |
193 | rq->sense_len = 0; | |
194 | rq->resid_len = 0; | |
195 | rq->sense = NULL; | |
196 | ||
af76e555 | 197 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
198 | rq->timeout = 0; |
199 | ||
af76e555 CH |
200 | rq->end_io = NULL; |
201 | rq->end_io_data = NULL; | |
202 | rq->next_rq = NULL; | |
203 | ||
320ae51f JA |
204 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
205 | } | |
206 | ||
5dee8577 | 207 | static struct request * |
cb96a42c | 208 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) |
5dee8577 CH |
209 | { |
210 | struct request *rq; | |
211 | unsigned int tag; | |
212 | ||
cb96a42c | 213 | tag = blk_mq_get_tag(data); |
5dee8577 | 214 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 215 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 216 | |
cb96a42c | 217 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 218 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 219 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
220 | } |
221 | ||
222 | rq->tag = tag; | |
cb96a42c | 223 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); |
5dee8577 CH |
224 | return rq; |
225 | } | |
226 | ||
227 | return NULL; | |
228 | } | |
229 | ||
4ce01dd1 CH |
230 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp, |
231 | bool reserved) | |
320ae51f | 232 | { |
d852564f CH |
233 | struct blk_mq_ctx *ctx; |
234 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 235 | struct request *rq; |
cb96a42c | 236 | struct blk_mq_alloc_data alloc_data; |
a492f075 | 237 | int ret; |
320ae51f | 238 | |
a492f075 JL |
239 | ret = blk_mq_queue_enter(q); |
240 | if (ret) | |
241 | return ERR_PTR(ret); | |
320ae51f | 242 | |
d852564f CH |
243 | ctx = blk_mq_get_ctx(q); |
244 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
245 | blk_mq_set_alloc_data(&alloc_data, q, gfp & ~__GFP_WAIT, |
246 | reserved, ctx, hctx); | |
d852564f | 247 | |
cb96a42c | 248 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
d852564f CH |
249 | if (!rq && (gfp & __GFP_WAIT)) { |
250 | __blk_mq_run_hw_queue(hctx); | |
251 | blk_mq_put_ctx(ctx); | |
252 | ||
253 | ctx = blk_mq_get_ctx(q); | |
254 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
255 | blk_mq_set_alloc_data(&alloc_data, q, gfp, reserved, ctx, |
256 | hctx); | |
257 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
258 | ctx = alloc_data.ctx; | |
d852564f CH |
259 | } |
260 | blk_mq_put_ctx(ctx); | |
a492f075 JL |
261 | if (!rq) |
262 | return ERR_PTR(-EWOULDBLOCK); | |
320ae51f JA |
263 | return rq; |
264 | } | |
4bb659b1 | 265 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 266 | |
320ae51f JA |
267 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
268 | struct blk_mq_ctx *ctx, struct request *rq) | |
269 | { | |
270 | const int tag = rq->tag; | |
271 | struct request_queue *q = rq->q; | |
272 | ||
0d2602ca JA |
273 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
274 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 275 | rq->cmd_flags = 0; |
0d2602ca | 276 | |
af76e555 | 277 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 278 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
320ae51f JA |
279 | blk_mq_queue_exit(q); |
280 | } | |
281 | ||
282 | void blk_mq_free_request(struct request *rq) | |
283 | { | |
284 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
285 | struct blk_mq_hw_ctx *hctx; | |
286 | struct request_queue *q = rq->q; | |
287 | ||
288 | ctx->rq_completed[rq_is_sync(rq)]++; | |
289 | ||
290 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
291 | __blk_mq_free_request(hctx, ctx, rq); | |
292 | } | |
293 | ||
c8a446ad | 294 | inline void __blk_mq_end_request(struct request *rq, int error) |
320ae51f | 295 | { |
0d11e6ac ML |
296 | blk_account_io_done(rq); |
297 | ||
91b63639 | 298 | if (rq->end_io) { |
320ae51f | 299 | rq->end_io(rq, error); |
91b63639 CH |
300 | } else { |
301 | if (unlikely(blk_bidi_rq(rq))) | |
302 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 303 | blk_mq_free_request(rq); |
91b63639 | 304 | } |
320ae51f | 305 | } |
c8a446ad | 306 | EXPORT_SYMBOL(__blk_mq_end_request); |
63151a44 | 307 | |
c8a446ad | 308 | void blk_mq_end_request(struct request *rq, int error) |
63151a44 CH |
309 | { |
310 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
311 | BUG(); | |
c8a446ad | 312 | __blk_mq_end_request(rq, error); |
63151a44 | 313 | } |
c8a446ad | 314 | EXPORT_SYMBOL(blk_mq_end_request); |
320ae51f | 315 | |
30a91cb4 | 316 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 317 | { |
3d6efbf6 | 318 | struct request *rq = data; |
320ae51f | 319 | |
30a91cb4 | 320 | rq->q->softirq_done_fn(rq); |
320ae51f | 321 | } |
320ae51f | 322 | |
ed851860 | 323 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
324 | { |
325 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 326 | bool shared = false; |
320ae51f JA |
327 | int cpu; |
328 | ||
38535201 | 329 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
330 | rq->q->softirq_done_fn(rq); |
331 | return; | |
332 | } | |
320ae51f JA |
333 | |
334 | cpu = get_cpu(); | |
38535201 CH |
335 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
336 | shared = cpus_share_cache(cpu, ctx->cpu); | |
337 | ||
338 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 339 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
340 | rq->csd.info = rq; |
341 | rq->csd.flags = 0; | |
c46fff2a | 342 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 343 | } else { |
30a91cb4 | 344 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 345 | } |
320ae51f JA |
346 | put_cpu(); |
347 | } | |
30a91cb4 | 348 | |
ed851860 JA |
349 | void __blk_mq_complete_request(struct request *rq) |
350 | { | |
351 | struct request_queue *q = rq->q; | |
352 | ||
353 | if (!q->softirq_done_fn) | |
c8a446ad | 354 | blk_mq_end_request(rq, rq->errors); |
ed851860 JA |
355 | else |
356 | blk_mq_ipi_complete_request(rq); | |
357 | } | |
358 | ||
30a91cb4 CH |
359 | /** |
360 | * blk_mq_complete_request - end I/O on a request | |
361 | * @rq: the request being processed | |
362 | * | |
363 | * Description: | |
364 | * Ends all I/O on a request. It does not handle partial completions. | |
365 | * The actual completion happens out-of-order, through a IPI handler. | |
366 | **/ | |
367 | void blk_mq_complete_request(struct request *rq) | |
368 | { | |
95f09684 JA |
369 | struct request_queue *q = rq->q; |
370 | ||
371 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 372 | return; |
ed851860 JA |
373 | if (!blk_mark_rq_complete(rq)) |
374 | __blk_mq_complete_request(rq); | |
30a91cb4 CH |
375 | } |
376 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 377 | |
e2490073 | 378 | void blk_mq_start_request(struct request *rq) |
320ae51f JA |
379 | { |
380 | struct request_queue *q = rq->q; | |
381 | ||
382 | trace_block_rq_issue(q, rq); | |
383 | ||
742ee69b | 384 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
385 | if (unlikely(blk_bidi_rq(rq))) |
386 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 387 | |
2b8393b4 | 388 | blk_add_timer(rq); |
87ee7b11 | 389 | |
538b7534 JA |
390 | /* |
391 | * Ensure that ->deadline is visible before set the started | |
392 | * flag and clear the completed flag. | |
393 | */ | |
394 | smp_mb__before_atomic(); | |
395 | ||
87ee7b11 JA |
396 | /* |
397 | * Mark us as started and clear complete. Complete might have been | |
398 | * set if requeue raced with timeout, which then marked it as | |
399 | * complete. So be sure to clear complete again when we start | |
400 | * the request, otherwise we'll ignore the completion event. | |
401 | */ | |
4b570521 JA |
402 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
403 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
404 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
405 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
406 | |
407 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
408 | /* | |
409 | * Make sure space for the drain appears. We know we can do | |
410 | * this because max_hw_segments has been adjusted to be one | |
411 | * fewer than the device can handle. | |
412 | */ | |
413 | rq->nr_phys_segments++; | |
414 | } | |
320ae51f | 415 | } |
e2490073 | 416 | EXPORT_SYMBOL(blk_mq_start_request); |
320ae51f | 417 | |
ed0791b2 | 418 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
419 | { |
420 | struct request_queue *q = rq->q; | |
421 | ||
422 | trace_block_rq_requeue(q, rq); | |
49f5baa5 | 423 | |
e2490073 CH |
424 | if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { |
425 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
426 | rq->nr_phys_segments--; | |
427 | } | |
320ae51f JA |
428 | } |
429 | ||
ed0791b2 CH |
430 | void blk_mq_requeue_request(struct request *rq) |
431 | { | |
ed0791b2 | 432 | __blk_mq_requeue_request(rq); |
ed0791b2 | 433 | |
ed0791b2 | 434 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 435 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
436 | } |
437 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
438 | ||
6fca6a61 CH |
439 | static void blk_mq_requeue_work(struct work_struct *work) |
440 | { | |
441 | struct request_queue *q = | |
442 | container_of(work, struct request_queue, requeue_work); | |
443 | LIST_HEAD(rq_list); | |
444 | struct request *rq, *next; | |
445 | unsigned long flags; | |
446 | ||
447 | spin_lock_irqsave(&q->requeue_lock, flags); | |
448 | list_splice_init(&q->requeue_list, &rq_list); | |
449 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
450 | ||
451 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
452 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
453 | continue; | |
454 | ||
455 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
456 | list_del_init(&rq->queuelist); | |
457 | blk_mq_insert_request(rq, true, false, false); | |
458 | } | |
459 | ||
460 | while (!list_empty(&rq_list)) { | |
461 | rq = list_entry(rq_list.next, struct request, queuelist); | |
462 | list_del_init(&rq->queuelist); | |
463 | blk_mq_insert_request(rq, false, false, false); | |
464 | } | |
465 | ||
8b957415 JA |
466 | /* |
467 | * Use the start variant of queue running here, so that running | |
468 | * the requeue work will kick stopped queues. | |
469 | */ | |
470 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
471 | } |
472 | ||
473 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
474 | { | |
475 | struct request_queue *q = rq->q; | |
476 | unsigned long flags; | |
477 | ||
478 | /* | |
479 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
480 | * request head insertation from the workqueue. | |
481 | */ | |
482 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
483 | ||
484 | spin_lock_irqsave(&q->requeue_lock, flags); | |
485 | if (at_head) { | |
486 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
487 | list_add(&rq->queuelist, &q->requeue_list); | |
488 | } else { | |
489 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
490 | } | |
491 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
492 | } | |
493 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
494 | ||
495 | void blk_mq_kick_requeue_list(struct request_queue *q) | |
496 | { | |
497 | kblockd_schedule_work(&q->requeue_work); | |
498 | } | |
499 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
500 | ||
7c94e1c1 ML |
501 | static inline bool is_flush_request(struct request *rq, |
502 | struct blk_flush_queue *fq, unsigned int tag) | |
24d2f903 | 503 | { |
0e62f51f | 504 | return ((rq->cmd_flags & REQ_FLUSH_SEQ) && |
7c94e1c1 | 505 | fq->flush_rq->tag == tag); |
0e62f51f JA |
506 | } |
507 | ||
508 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) | |
509 | { | |
510 | struct request *rq = tags->rqs[tag]; | |
e97c293c ML |
511 | /* mq_ctx of flush rq is always cloned from the corresponding req */ |
512 | struct blk_flush_queue *fq = blk_get_flush_queue(rq->q, rq->mq_ctx); | |
22302375 | 513 | |
7c94e1c1 | 514 | if (!is_flush_request(rq, fq, tag)) |
0e62f51f | 515 | return rq; |
22302375 | 516 | |
7c94e1c1 | 517 | return fq->flush_rq; |
24d2f903 CH |
518 | } |
519 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
520 | ||
320ae51f | 521 | struct blk_mq_timeout_data { |
46f92d42 CH |
522 | unsigned long next; |
523 | unsigned int next_set; | |
320ae51f JA |
524 | }; |
525 | ||
90415837 | 526 | void blk_mq_rq_timed_out(struct request *req, bool reserved) |
320ae51f | 527 | { |
46f92d42 CH |
528 | struct blk_mq_ops *ops = req->q->mq_ops; |
529 | enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER; | |
87ee7b11 JA |
530 | |
531 | /* | |
532 | * We know that complete is set at this point. If STARTED isn't set | |
533 | * anymore, then the request isn't active and the "timeout" should | |
534 | * just be ignored. This can happen due to the bitflag ordering. | |
535 | * Timeout first checks if STARTED is set, and if it is, assumes | |
536 | * the request is active. But if we race with completion, then | |
537 | * we both flags will get cleared. So check here again, and ignore | |
538 | * a timeout event with a request that isn't active. | |
539 | */ | |
46f92d42 CH |
540 | if (!test_bit(REQ_ATOM_STARTED, &req->atomic_flags)) |
541 | return; | |
87ee7b11 | 542 | |
46f92d42 | 543 | if (ops->timeout) |
0152fb6b | 544 | ret = ops->timeout(req, reserved); |
46f92d42 CH |
545 | |
546 | switch (ret) { | |
547 | case BLK_EH_HANDLED: | |
548 | __blk_mq_complete_request(req); | |
549 | break; | |
550 | case BLK_EH_RESET_TIMER: | |
551 | blk_add_timer(req); | |
552 | blk_clear_rq_complete(req); | |
553 | break; | |
554 | case BLK_EH_NOT_HANDLED: | |
555 | break; | |
556 | default: | |
557 | printk(KERN_ERR "block: bad eh return: %d\n", ret); | |
558 | break; | |
559 | } | |
87ee7b11 | 560 | } |
81481eb4 | 561 | |
81481eb4 CH |
562 | static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, |
563 | struct request *rq, void *priv, bool reserved) | |
564 | { | |
565 | struct blk_mq_timeout_data *data = priv; | |
87ee7b11 | 566 | |
46f92d42 CH |
567 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
568 | return; | |
87ee7b11 | 569 | |
46f92d42 CH |
570 | if (time_after_eq(jiffies, rq->deadline)) { |
571 | if (!blk_mark_rq_complete(rq)) | |
0152fb6b | 572 | blk_mq_rq_timed_out(rq, reserved); |
46f92d42 CH |
573 | } else if (!data->next_set || time_after(data->next, rq->deadline)) { |
574 | data->next = rq->deadline; | |
575 | data->next_set = 1; | |
576 | } | |
87ee7b11 JA |
577 | } |
578 | ||
81481eb4 | 579 | static void blk_mq_rq_timer(unsigned long priv) |
320ae51f | 580 | { |
81481eb4 CH |
581 | struct request_queue *q = (struct request_queue *)priv; |
582 | struct blk_mq_timeout_data data = { | |
583 | .next = 0, | |
584 | .next_set = 0, | |
585 | }; | |
320ae51f | 586 | struct blk_mq_hw_ctx *hctx; |
81481eb4 | 587 | int i; |
320ae51f | 588 | |
484b4061 JA |
589 | queue_for_each_hw_ctx(q, hctx, i) { |
590 | /* | |
591 | * If not software queues are currently mapped to this | |
592 | * hardware queue, there's nothing to check | |
593 | */ | |
594 | if (!hctx->nr_ctx || !hctx->tags) | |
595 | continue; | |
596 | ||
81481eb4 | 597 | blk_mq_tag_busy_iter(hctx, blk_mq_check_expired, &data); |
484b4061 | 598 | } |
320ae51f | 599 | |
81481eb4 CH |
600 | if (data.next_set) { |
601 | data.next = blk_rq_timeout(round_jiffies_up(data.next)); | |
602 | mod_timer(&q->timeout, data.next); | |
0d2602ca JA |
603 | } else { |
604 | queue_for_each_hw_ctx(q, hctx, i) | |
605 | blk_mq_tag_idle(hctx); | |
606 | } | |
320ae51f JA |
607 | } |
608 | ||
609 | /* | |
610 | * Reverse check our software queue for entries that we could potentially | |
611 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
612 | * too much time checking for merges. | |
613 | */ | |
614 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
615 | struct blk_mq_ctx *ctx, struct bio *bio) | |
616 | { | |
617 | struct request *rq; | |
618 | int checked = 8; | |
619 | ||
620 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
621 | int el_ret; | |
622 | ||
623 | if (!checked--) | |
624 | break; | |
625 | ||
626 | if (!blk_rq_merge_ok(rq, bio)) | |
627 | continue; | |
628 | ||
629 | el_ret = blk_try_merge(rq, bio); | |
630 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
631 | if (bio_attempt_back_merge(q, rq, bio)) { | |
632 | ctx->rq_merged++; | |
633 | return true; | |
634 | } | |
635 | break; | |
636 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
637 | if (bio_attempt_front_merge(q, rq, bio)) { | |
638 | ctx->rq_merged++; | |
639 | return true; | |
640 | } | |
641 | break; | |
642 | } | |
643 | } | |
644 | ||
645 | return false; | |
646 | } | |
647 | ||
1429d7c9 JA |
648 | /* |
649 | * Process software queues that have been marked busy, splicing them | |
650 | * to the for-dispatch | |
651 | */ | |
652 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
653 | { | |
654 | struct blk_mq_ctx *ctx; | |
655 | int i; | |
656 | ||
657 | for (i = 0; i < hctx->ctx_map.map_size; i++) { | |
658 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; | |
659 | unsigned int off, bit; | |
660 | ||
661 | if (!bm->word) | |
662 | continue; | |
663 | ||
664 | bit = 0; | |
665 | off = i * hctx->ctx_map.bits_per_word; | |
666 | do { | |
667 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
668 | if (bit >= bm->depth) | |
669 | break; | |
670 | ||
671 | ctx = hctx->ctxs[bit + off]; | |
672 | clear_bit(bit, &bm->word); | |
673 | spin_lock(&ctx->lock); | |
674 | list_splice_tail_init(&ctx->rq_list, list); | |
675 | spin_unlock(&ctx->lock); | |
676 | ||
677 | bit++; | |
678 | } while (1); | |
679 | } | |
680 | } | |
681 | ||
320ae51f JA |
682 | /* |
683 | * Run this hardware queue, pulling any software queues mapped to it in. | |
684 | * Note that this function currently has various problems around ordering | |
685 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
686 | * items on the hctx->dispatch list. Ignore that for now. | |
687 | */ | |
688 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
689 | { | |
690 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
691 | struct request *rq; |
692 | LIST_HEAD(rq_list); | |
1429d7c9 | 693 | int queued; |
320ae51f | 694 | |
fd1270d5 | 695 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 696 | |
5d12f905 | 697 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
698 | return; |
699 | ||
700 | hctx->run++; | |
701 | ||
702 | /* | |
703 | * Touch any software queue that has pending entries. | |
704 | */ | |
1429d7c9 | 705 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
706 | |
707 | /* | |
708 | * If we have previous entries on our dispatch list, grab them | |
709 | * and stuff them at the front for more fair dispatch. | |
710 | */ | |
711 | if (!list_empty_careful(&hctx->dispatch)) { | |
712 | spin_lock(&hctx->lock); | |
713 | if (!list_empty(&hctx->dispatch)) | |
714 | list_splice_init(&hctx->dispatch, &rq_list); | |
715 | spin_unlock(&hctx->lock); | |
716 | } | |
717 | ||
320ae51f JA |
718 | /* |
719 | * Now process all the entries, sending them to the driver. | |
720 | */ | |
1429d7c9 | 721 | queued = 0; |
320ae51f JA |
722 | while (!list_empty(&rq_list)) { |
723 | int ret; | |
724 | ||
725 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
726 | list_del_init(&rq->queuelist); | |
320ae51f | 727 | |
bf572297 | 728 | ret = q->mq_ops->queue_rq(hctx, rq, list_empty(&rq_list)); |
320ae51f JA |
729 | switch (ret) { |
730 | case BLK_MQ_RQ_QUEUE_OK: | |
731 | queued++; | |
732 | continue; | |
733 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 734 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 735 | __blk_mq_requeue_request(rq); |
320ae51f JA |
736 | break; |
737 | default: | |
738 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 739 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 740 | rq->errors = -EIO; |
c8a446ad | 741 | blk_mq_end_request(rq, rq->errors); |
320ae51f JA |
742 | break; |
743 | } | |
744 | ||
745 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
746 | break; | |
747 | } | |
748 | ||
749 | if (!queued) | |
750 | hctx->dispatched[0]++; | |
751 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
752 | hctx->dispatched[ilog2(queued) + 1]++; | |
753 | ||
754 | /* | |
755 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
756 | * that is where we will continue on next queue run. | |
757 | */ | |
758 | if (!list_empty(&rq_list)) { | |
759 | spin_lock(&hctx->lock); | |
760 | list_splice(&rq_list, &hctx->dispatch); | |
761 | spin_unlock(&hctx->lock); | |
762 | } | |
763 | } | |
764 | ||
506e931f JA |
765 | /* |
766 | * It'd be great if the workqueue API had a way to pass | |
767 | * in a mask and had some smarts for more clever placement. | |
768 | * For now we just round-robin here, switching for every | |
769 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
770 | */ | |
771 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
772 | { | |
773 | int cpu = hctx->next_cpu; | |
774 | ||
775 | if (--hctx->next_cpu_batch <= 0) { | |
776 | int next_cpu; | |
777 | ||
778 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
779 | if (next_cpu >= nr_cpu_ids) | |
780 | next_cpu = cpumask_first(hctx->cpumask); | |
781 | ||
782 | hctx->next_cpu = next_cpu; | |
783 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
784 | } | |
785 | ||
786 | return cpu; | |
787 | } | |
788 | ||
320ae51f JA |
789 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
790 | { | |
5d12f905 | 791 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
792 | return; |
793 | ||
e4043dcf | 794 | if (!async && cpumask_test_cpu(smp_processor_id(), hctx->cpumask)) |
320ae51f | 795 | __blk_mq_run_hw_queue(hctx); |
e4043dcf | 796 | else if (hctx->queue->nr_hw_queues == 1) |
70f4db63 | 797 | kblockd_schedule_delayed_work(&hctx->run_work, 0); |
e4043dcf JA |
798 | else { |
799 | unsigned int cpu; | |
800 | ||
506e931f | 801 | cpu = blk_mq_hctx_next_cpu(hctx); |
70f4db63 | 802 | kblockd_schedule_delayed_work_on(cpu, &hctx->run_work, 0); |
e4043dcf | 803 | } |
320ae51f JA |
804 | } |
805 | ||
806 | void blk_mq_run_queues(struct request_queue *q, bool async) | |
807 | { | |
808 | struct blk_mq_hw_ctx *hctx; | |
809 | int i; | |
810 | ||
811 | queue_for_each_hw_ctx(q, hctx, i) { | |
812 | if ((!blk_mq_hctx_has_pending(hctx) && | |
813 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 814 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
815 | continue; |
816 | ||
e4043dcf | 817 | preempt_disable(); |
320ae51f | 818 | blk_mq_run_hw_queue(hctx, async); |
e4043dcf | 819 | preempt_enable(); |
320ae51f JA |
820 | } |
821 | } | |
822 | EXPORT_SYMBOL(blk_mq_run_queues); | |
823 | ||
824 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
825 | { | |
70f4db63 CH |
826 | cancel_delayed_work(&hctx->run_work); |
827 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
828 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
829 | } | |
830 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
831 | ||
280d45f6 CH |
832 | void blk_mq_stop_hw_queues(struct request_queue *q) |
833 | { | |
834 | struct blk_mq_hw_ctx *hctx; | |
835 | int i; | |
836 | ||
837 | queue_for_each_hw_ctx(q, hctx, i) | |
838 | blk_mq_stop_hw_queue(hctx); | |
839 | } | |
840 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
841 | ||
320ae51f JA |
842 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
843 | { | |
844 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf JA |
845 | |
846 | preempt_disable(); | |
0ffbce80 | 847 | blk_mq_run_hw_queue(hctx, false); |
e4043dcf | 848 | preempt_enable(); |
320ae51f JA |
849 | } |
850 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
851 | ||
2f268556 CH |
852 | void blk_mq_start_hw_queues(struct request_queue *q) |
853 | { | |
854 | struct blk_mq_hw_ctx *hctx; | |
855 | int i; | |
856 | ||
857 | queue_for_each_hw_ctx(q, hctx, i) | |
858 | blk_mq_start_hw_queue(hctx); | |
859 | } | |
860 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
861 | ||
862 | ||
1b4a3258 | 863 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
864 | { |
865 | struct blk_mq_hw_ctx *hctx; | |
866 | int i; | |
867 | ||
868 | queue_for_each_hw_ctx(q, hctx, i) { | |
869 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
870 | continue; | |
871 | ||
872 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 873 | preempt_disable(); |
1b4a3258 | 874 | blk_mq_run_hw_queue(hctx, async); |
e4043dcf | 875 | preempt_enable(); |
320ae51f JA |
876 | } |
877 | } | |
878 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
879 | ||
70f4db63 | 880 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
881 | { |
882 | struct blk_mq_hw_ctx *hctx; | |
883 | ||
70f4db63 | 884 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 885 | |
320ae51f JA |
886 | __blk_mq_run_hw_queue(hctx); |
887 | } | |
888 | ||
70f4db63 CH |
889 | static void blk_mq_delay_work_fn(struct work_struct *work) |
890 | { | |
891 | struct blk_mq_hw_ctx *hctx; | |
892 | ||
893 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
894 | ||
895 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
896 | __blk_mq_run_hw_queue(hctx); | |
897 | } | |
898 | ||
899 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
900 | { | |
901 | unsigned long tmo = msecs_to_jiffies(msecs); | |
902 | ||
903 | if (hctx->queue->nr_hw_queues == 1) | |
904 | kblockd_schedule_delayed_work(&hctx->delay_work, tmo); | |
905 | else { | |
906 | unsigned int cpu; | |
907 | ||
506e931f | 908 | cpu = blk_mq_hctx_next_cpu(hctx); |
70f4db63 CH |
909 | kblockd_schedule_delayed_work_on(cpu, &hctx->delay_work, tmo); |
910 | } | |
911 | } | |
912 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
913 | ||
320ae51f | 914 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
72a0a36e | 915 | struct request *rq, bool at_head) |
320ae51f JA |
916 | { |
917 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
918 | ||
01b983c9 JA |
919 | trace_block_rq_insert(hctx->queue, rq); |
920 | ||
72a0a36e CH |
921 | if (at_head) |
922 | list_add(&rq->queuelist, &ctx->rq_list); | |
923 | else | |
924 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
4bb659b1 | 925 | |
320ae51f | 926 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
927 | } |
928 | ||
eeabc850 CH |
929 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
930 | bool async) | |
320ae51f | 931 | { |
eeabc850 | 932 | struct request_queue *q = rq->q; |
320ae51f | 933 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
934 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
935 | ||
936 | current_ctx = blk_mq_get_ctx(q); | |
937 | if (!cpu_online(ctx->cpu)) | |
938 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 939 | |
320ae51f JA |
940 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
941 | ||
a57a178a CH |
942 | spin_lock(&ctx->lock); |
943 | __blk_mq_insert_request(hctx, rq, at_head); | |
944 | spin_unlock(&ctx->lock); | |
320ae51f | 945 | |
320ae51f JA |
946 | if (run_queue) |
947 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
948 | |
949 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
950 | } |
951 | ||
952 | static void blk_mq_insert_requests(struct request_queue *q, | |
953 | struct blk_mq_ctx *ctx, | |
954 | struct list_head *list, | |
955 | int depth, | |
956 | bool from_schedule) | |
957 | ||
958 | { | |
959 | struct blk_mq_hw_ctx *hctx; | |
960 | struct blk_mq_ctx *current_ctx; | |
961 | ||
962 | trace_block_unplug(q, depth, !from_schedule); | |
963 | ||
964 | current_ctx = blk_mq_get_ctx(q); | |
965 | ||
966 | if (!cpu_online(ctx->cpu)) | |
967 | ctx = current_ctx; | |
968 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
969 | ||
970 | /* | |
971 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
972 | * offline now | |
973 | */ | |
974 | spin_lock(&ctx->lock); | |
975 | while (!list_empty(list)) { | |
976 | struct request *rq; | |
977 | ||
978 | rq = list_first_entry(list, struct request, queuelist); | |
979 | list_del_init(&rq->queuelist); | |
980 | rq->mq_ctx = ctx; | |
72a0a36e | 981 | __blk_mq_insert_request(hctx, rq, false); |
320ae51f JA |
982 | } |
983 | spin_unlock(&ctx->lock); | |
984 | ||
320ae51f | 985 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 986 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
987 | } |
988 | ||
989 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
990 | { | |
991 | struct request *rqa = container_of(a, struct request, queuelist); | |
992 | struct request *rqb = container_of(b, struct request, queuelist); | |
993 | ||
994 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
995 | (rqa->mq_ctx == rqb->mq_ctx && | |
996 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
997 | } | |
998 | ||
999 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1000 | { | |
1001 | struct blk_mq_ctx *this_ctx; | |
1002 | struct request_queue *this_q; | |
1003 | struct request *rq; | |
1004 | LIST_HEAD(list); | |
1005 | LIST_HEAD(ctx_list); | |
1006 | unsigned int depth; | |
1007 | ||
1008 | list_splice_init(&plug->mq_list, &list); | |
1009 | ||
1010 | list_sort(NULL, &list, plug_ctx_cmp); | |
1011 | ||
1012 | this_q = NULL; | |
1013 | this_ctx = NULL; | |
1014 | depth = 0; | |
1015 | ||
1016 | while (!list_empty(&list)) { | |
1017 | rq = list_entry_rq(list.next); | |
1018 | list_del_init(&rq->queuelist); | |
1019 | BUG_ON(!rq->q); | |
1020 | if (rq->mq_ctx != this_ctx) { | |
1021 | if (this_ctx) { | |
1022 | blk_mq_insert_requests(this_q, this_ctx, | |
1023 | &ctx_list, depth, | |
1024 | from_schedule); | |
1025 | } | |
1026 | ||
1027 | this_ctx = rq->mq_ctx; | |
1028 | this_q = rq->q; | |
1029 | depth = 0; | |
1030 | } | |
1031 | ||
1032 | depth++; | |
1033 | list_add_tail(&rq->queuelist, &ctx_list); | |
1034 | } | |
1035 | ||
1036 | /* | |
1037 | * If 'this_ctx' is set, we know we have entries to complete | |
1038 | * on 'ctx_list'. Do those. | |
1039 | */ | |
1040 | if (this_ctx) { | |
1041 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1042 | from_schedule); | |
1043 | } | |
1044 | } | |
1045 | ||
1046 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1047 | { | |
1048 | init_request_from_bio(rq, bio); | |
4b570521 | 1049 | |
3ee32372 | 1050 | if (blk_do_io_stat(rq)) |
4b570521 | 1051 | blk_account_io_start(rq, 1); |
320ae51f JA |
1052 | } |
1053 | ||
274a5843 JA |
1054 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1055 | { | |
1056 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1057 | !blk_queue_nomerges(hctx->queue); | |
1058 | } | |
1059 | ||
07068d5b JA |
1060 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1061 | struct blk_mq_ctx *ctx, | |
1062 | struct request *rq, struct bio *bio) | |
320ae51f | 1063 | { |
274a5843 | 1064 | if (!hctx_allow_merges(hctx)) { |
07068d5b JA |
1065 | blk_mq_bio_to_request(rq, bio); |
1066 | spin_lock(&ctx->lock); | |
1067 | insert_rq: | |
1068 | __blk_mq_insert_request(hctx, rq, false); | |
1069 | spin_unlock(&ctx->lock); | |
1070 | return false; | |
1071 | } else { | |
274a5843 JA |
1072 | struct request_queue *q = hctx->queue; |
1073 | ||
07068d5b JA |
1074 | spin_lock(&ctx->lock); |
1075 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1076 | blk_mq_bio_to_request(rq, bio); | |
1077 | goto insert_rq; | |
1078 | } | |
320ae51f | 1079 | |
07068d5b JA |
1080 | spin_unlock(&ctx->lock); |
1081 | __blk_mq_free_request(hctx, ctx, rq); | |
1082 | return true; | |
14ec77f3 | 1083 | } |
07068d5b | 1084 | } |
14ec77f3 | 1085 | |
07068d5b JA |
1086 | struct blk_map_ctx { |
1087 | struct blk_mq_hw_ctx *hctx; | |
1088 | struct blk_mq_ctx *ctx; | |
1089 | }; | |
1090 | ||
1091 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1092 | struct bio *bio, | |
1093 | struct blk_map_ctx *data) | |
1094 | { | |
1095 | struct blk_mq_hw_ctx *hctx; | |
1096 | struct blk_mq_ctx *ctx; | |
1097 | struct request *rq; | |
1098 | int rw = bio_data_dir(bio); | |
cb96a42c | 1099 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1100 | |
07068d5b | 1101 | if (unlikely(blk_mq_queue_enter(q))) { |
320ae51f | 1102 | bio_endio(bio, -EIO); |
07068d5b | 1103 | return NULL; |
320ae51f JA |
1104 | } |
1105 | ||
1106 | ctx = blk_mq_get_ctx(q); | |
1107 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1108 | ||
07068d5b | 1109 | if (rw_is_sync(bio->bi_rw)) |
27fbf4e8 | 1110 | rw |= REQ_SYNC; |
07068d5b | 1111 | |
320ae51f | 1112 | trace_block_getrq(q, bio, rw); |
cb96a42c ML |
1113 | blk_mq_set_alloc_data(&alloc_data, q, GFP_ATOMIC, false, ctx, |
1114 | hctx); | |
1115 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
5dee8577 | 1116 | if (unlikely(!rq)) { |
793597a6 | 1117 | __blk_mq_run_hw_queue(hctx); |
320ae51f JA |
1118 | blk_mq_put_ctx(ctx); |
1119 | trace_block_sleeprq(q, bio, rw); | |
793597a6 CH |
1120 | |
1121 | ctx = blk_mq_get_ctx(q); | |
320ae51f | 1122 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
cb96a42c ML |
1123 | blk_mq_set_alloc_data(&alloc_data, q, |
1124 | __GFP_WAIT|GFP_ATOMIC, false, ctx, hctx); | |
1125 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
1126 | ctx = alloc_data.ctx; | |
1127 | hctx = alloc_data.hctx; | |
320ae51f JA |
1128 | } |
1129 | ||
1130 | hctx->queued++; | |
07068d5b JA |
1131 | data->hctx = hctx; |
1132 | data->ctx = ctx; | |
1133 | return rq; | |
1134 | } | |
1135 | ||
1136 | /* | |
1137 | * Multiple hardware queue variant. This will not use per-process plugs, | |
1138 | * but will attempt to bypass the hctx queueing if we can go straight to | |
1139 | * hardware for SYNC IO. | |
1140 | */ | |
1141 | static void blk_mq_make_request(struct request_queue *q, struct bio *bio) | |
1142 | { | |
1143 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1144 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1145 | struct blk_map_ctx data; | |
1146 | struct request *rq; | |
1147 | ||
1148 | blk_queue_bounce(q, &bio); | |
1149 | ||
1150 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1151 | bio_endio(bio, -EIO); | |
1152 | return; | |
1153 | } | |
1154 | ||
1155 | rq = blk_mq_map_request(q, bio, &data); | |
1156 | if (unlikely(!rq)) | |
1157 | return; | |
1158 | ||
1159 | if (unlikely(is_flush_fua)) { | |
1160 | blk_mq_bio_to_request(rq, bio); | |
1161 | blk_insert_flush(rq); | |
1162 | goto run_queue; | |
1163 | } | |
1164 | ||
1165 | if (is_sync) { | |
1166 | int ret; | |
1167 | ||
1168 | blk_mq_bio_to_request(rq, bio); | |
07068d5b JA |
1169 | |
1170 | /* | |
1171 | * For OK queue, we are done. For error, kill it. Any other | |
1172 | * error (busy), just add it to our list as we previously | |
1173 | * would have done | |
1174 | */ | |
bf572297 | 1175 | ret = q->mq_ops->queue_rq(data.hctx, rq, true); |
07068d5b JA |
1176 | if (ret == BLK_MQ_RQ_QUEUE_OK) |
1177 | goto done; | |
1178 | else { | |
1179 | __blk_mq_requeue_request(rq); | |
1180 | ||
1181 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1182 | rq->errors = -EIO; | |
c8a446ad | 1183 | blk_mq_end_request(rq, rq->errors); |
07068d5b JA |
1184 | goto done; |
1185 | } | |
1186 | } | |
1187 | } | |
1188 | ||
1189 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { | |
1190 | /* | |
1191 | * For a SYNC request, send it to the hardware immediately. For | |
1192 | * an ASYNC request, just ensure that we run it later on. The | |
1193 | * latter allows for merging opportunities and more efficient | |
1194 | * dispatching. | |
1195 | */ | |
1196 | run_queue: | |
1197 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
1198 | } | |
1199 | done: | |
1200 | blk_mq_put_ctx(data.ctx); | |
1201 | } | |
1202 | ||
1203 | /* | |
1204 | * Single hardware queue variant. This will attempt to use any per-process | |
1205 | * plug for merging and IO deferral. | |
1206 | */ | |
1207 | static void blk_sq_make_request(struct request_queue *q, struct bio *bio) | |
1208 | { | |
1209 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1210 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1211 | unsigned int use_plug, request_count = 0; | |
1212 | struct blk_map_ctx data; | |
1213 | struct request *rq; | |
1214 | ||
1215 | /* | |
1216 | * If we have multiple hardware queues, just go directly to | |
1217 | * one of those for sync IO. | |
1218 | */ | |
1219 | use_plug = !is_flush_fua && !is_sync; | |
1220 | ||
1221 | blk_queue_bounce(q, &bio); | |
1222 | ||
1223 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1224 | bio_endio(bio, -EIO); | |
1225 | return; | |
1226 | } | |
1227 | ||
1228 | if (use_plug && !blk_queue_nomerges(q) && | |
1229 | blk_attempt_plug_merge(q, bio, &request_count)) | |
1230 | return; | |
1231 | ||
1232 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec JA |
1233 | if (unlikely(!rq)) |
1234 | return; | |
320ae51f JA |
1235 | |
1236 | if (unlikely(is_flush_fua)) { | |
1237 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1238 | blk_insert_flush(rq); |
1239 | goto run_queue; | |
1240 | } | |
1241 | ||
1242 | /* | |
1243 | * A task plug currently exists. Since this is completely lockless, | |
1244 | * utilize that to temporarily store requests until the task is | |
1245 | * either done or scheduled away. | |
1246 | */ | |
1247 | if (use_plug) { | |
1248 | struct blk_plug *plug = current->plug; | |
1249 | ||
1250 | if (plug) { | |
1251 | blk_mq_bio_to_request(rq, bio); | |
92f399c7 | 1252 | if (list_empty(&plug->mq_list)) |
320ae51f JA |
1253 | trace_block_plug(q); |
1254 | else if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
1255 | blk_flush_plug_list(plug, false); | |
1256 | trace_block_plug(q); | |
1257 | } | |
1258 | list_add_tail(&rq->queuelist, &plug->mq_list); | |
07068d5b | 1259 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1260 | return; |
1261 | } | |
1262 | } | |
1263 | ||
07068d5b JA |
1264 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1265 | /* | |
1266 | * For a SYNC request, send it to the hardware immediately. For | |
1267 | * an ASYNC request, just ensure that we run it later on. The | |
1268 | * latter allows for merging opportunities and more efficient | |
1269 | * dispatching. | |
1270 | */ | |
1271 | run_queue: | |
1272 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1273 | } |
1274 | ||
07068d5b | 1275 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1276 | } |
1277 | ||
1278 | /* | |
1279 | * Default mapping to a software queue, since we use one per CPU. | |
1280 | */ | |
1281 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1282 | { | |
1283 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1284 | } | |
1285 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1286 | ||
24d2f903 CH |
1287 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1288 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1289 | { |
e9b267d9 | 1290 | struct page *page; |
320ae51f | 1291 | |
24d2f903 | 1292 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1293 | int i; |
320ae51f | 1294 | |
24d2f903 CH |
1295 | for (i = 0; i < tags->nr_tags; i++) { |
1296 | if (!tags->rqs[i]) | |
e9b267d9 | 1297 | continue; |
24d2f903 CH |
1298 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1299 | hctx_idx, i); | |
a5164405 | 1300 | tags->rqs[i] = NULL; |
e9b267d9 | 1301 | } |
320ae51f | 1302 | } |
320ae51f | 1303 | |
24d2f903 CH |
1304 | while (!list_empty(&tags->page_list)) { |
1305 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1306 | list_del_init(&page->lru); |
320ae51f JA |
1307 | __free_pages(page, page->private); |
1308 | } | |
1309 | ||
24d2f903 | 1310 | kfree(tags->rqs); |
320ae51f | 1311 | |
24d2f903 | 1312 | blk_mq_free_tags(tags); |
320ae51f JA |
1313 | } |
1314 | ||
1315 | static size_t order_to_size(unsigned int order) | |
1316 | { | |
4ca08500 | 1317 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1318 | } |
1319 | ||
24d2f903 CH |
1320 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1321 | unsigned int hctx_idx) | |
320ae51f | 1322 | { |
24d2f903 | 1323 | struct blk_mq_tags *tags; |
320ae51f JA |
1324 | unsigned int i, j, entries_per_page, max_order = 4; |
1325 | size_t rq_size, left; | |
1326 | ||
24d2f903 CH |
1327 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
1328 | set->numa_node); | |
1329 | if (!tags) | |
1330 | return NULL; | |
320ae51f | 1331 | |
24d2f903 CH |
1332 | INIT_LIST_HEAD(&tags->page_list); |
1333 | ||
a5164405 JA |
1334 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1335 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1336 | set->numa_node); | |
24d2f903 CH |
1337 | if (!tags->rqs) { |
1338 | blk_mq_free_tags(tags); | |
1339 | return NULL; | |
1340 | } | |
320ae51f JA |
1341 | |
1342 | /* | |
1343 | * rq_size is the size of the request plus driver payload, rounded | |
1344 | * to the cacheline size | |
1345 | */ | |
24d2f903 | 1346 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1347 | cache_line_size()); |
24d2f903 | 1348 | left = rq_size * set->queue_depth; |
320ae51f | 1349 | |
24d2f903 | 1350 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1351 | int this_order = max_order; |
1352 | struct page *page; | |
1353 | int to_do; | |
1354 | void *p; | |
1355 | ||
1356 | while (left < order_to_size(this_order - 1) && this_order) | |
1357 | this_order--; | |
1358 | ||
1359 | do { | |
a5164405 JA |
1360 | page = alloc_pages_node(set->numa_node, |
1361 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1362 | this_order); | |
320ae51f JA |
1363 | if (page) |
1364 | break; | |
1365 | if (!this_order--) | |
1366 | break; | |
1367 | if (order_to_size(this_order) < rq_size) | |
1368 | break; | |
1369 | } while (1); | |
1370 | ||
1371 | if (!page) | |
24d2f903 | 1372 | goto fail; |
320ae51f JA |
1373 | |
1374 | page->private = this_order; | |
24d2f903 | 1375 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1376 | |
1377 | p = page_address(page); | |
1378 | entries_per_page = order_to_size(this_order) / rq_size; | |
24d2f903 | 1379 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1380 | left -= to_do * rq_size; |
1381 | for (j = 0; j < to_do; j++) { | |
24d2f903 | 1382 | tags->rqs[i] = p; |
683d0e12 DH |
1383 | tags->rqs[i]->atomic_flags = 0; |
1384 | tags->rqs[i]->cmd_flags = 0; | |
24d2f903 CH |
1385 | if (set->ops->init_request) { |
1386 | if (set->ops->init_request(set->driver_data, | |
1387 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1388 | set->numa_node)) { |
1389 | tags->rqs[i] = NULL; | |
24d2f903 | 1390 | goto fail; |
a5164405 | 1391 | } |
e9b267d9 CH |
1392 | } |
1393 | ||
320ae51f JA |
1394 | p += rq_size; |
1395 | i++; | |
1396 | } | |
1397 | } | |
1398 | ||
24d2f903 | 1399 | return tags; |
320ae51f | 1400 | |
24d2f903 | 1401 | fail: |
24d2f903 CH |
1402 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1403 | return NULL; | |
320ae51f JA |
1404 | } |
1405 | ||
1429d7c9 JA |
1406 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1407 | { | |
1408 | kfree(bitmap->map); | |
1409 | } | |
1410 | ||
1411 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1412 | { | |
1413 | unsigned int bpw = 8, total, num_maps, i; | |
1414 | ||
1415 | bitmap->bits_per_word = bpw; | |
1416 | ||
1417 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1418 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1419 | GFP_KERNEL, node); | |
1420 | if (!bitmap->map) | |
1421 | return -ENOMEM; | |
1422 | ||
1423 | bitmap->map_size = num_maps; | |
1424 | ||
1425 | total = nr_cpu_ids; | |
1426 | for (i = 0; i < num_maps; i++) { | |
1427 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1428 | total -= bitmap->map[i].depth; | |
1429 | } | |
1430 | ||
1431 | return 0; | |
1432 | } | |
1433 | ||
484b4061 JA |
1434 | static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) |
1435 | { | |
1436 | struct request_queue *q = hctx->queue; | |
1437 | struct blk_mq_ctx *ctx; | |
1438 | LIST_HEAD(tmp); | |
1439 | ||
1440 | /* | |
1441 | * Move ctx entries to new CPU, if this one is going away. | |
1442 | */ | |
1443 | ctx = __blk_mq_get_ctx(q, cpu); | |
1444 | ||
1445 | spin_lock(&ctx->lock); | |
1446 | if (!list_empty(&ctx->rq_list)) { | |
1447 | list_splice_init(&ctx->rq_list, &tmp); | |
1448 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1449 | } | |
1450 | spin_unlock(&ctx->lock); | |
1451 | ||
1452 | if (list_empty(&tmp)) | |
1453 | return NOTIFY_OK; | |
1454 | ||
1455 | ctx = blk_mq_get_ctx(q); | |
1456 | spin_lock(&ctx->lock); | |
1457 | ||
1458 | while (!list_empty(&tmp)) { | |
1459 | struct request *rq; | |
1460 | ||
1461 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1462 | rq->mq_ctx = ctx; | |
1463 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1464 | } | |
1465 | ||
1466 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1467 | blk_mq_hctx_mark_pending(hctx, ctx); | |
1468 | ||
1469 | spin_unlock(&ctx->lock); | |
1470 | ||
1471 | blk_mq_run_hw_queue(hctx, true); | |
1472 | blk_mq_put_ctx(ctx); | |
1473 | return NOTIFY_OK; | |
1474 | } | |
1475 | ||
1476 | static int blk_mq_hctx_cpu_online(struct blk_mq_hw_ctx *hctx, int cpu) | |
1477 | { | |
1478 | struct request_queue *q = hctx->queue; | |
1479 | struct blk_mq_tag_set *set = q->tag_set; | |
1480 | ||
1481 | if (set->tags[hctx->queue_num]) | |
1482 | return NOTIFY_OK; | |
1483 | ||
1484 | set->tags[hctx->queue_num] = blk_mq_init_rq_map(set, hctx->queue_num); | |
1485 | if (!set->tags[hctx->queue_num]) | |
1486 | return NOTIFY_STOP; | |
1487 | ||
1488 | hctx->tags = set->tags[hctx->queue_num]; | |
1489 | return NOTIFY_OK; | |
1490 | } | |
1491 | ||
1492 | static int blk_mq_hctx_notify(void *data, unsigned long action, | |
1493 | unsigned int cpu) | |
1494 | { | |
1495 | struct blk_mq_hw_ctx *hctx = data; | |
1496 | ||
1497 | if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) | |
1498 | return blk_mq_hctx_cpu_offline(hctx, cpu); | |
1499 | else if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) | |
1500 | return blk_mq_hctx_cpu_online(hctx, cpu); | |
1501 | ||
1502 | return NOTIFY_OK; | |
1503 | } | |
1504 | ||
08e98fc6 ML |
1505 | static void blk_mq_exit_hctx(struct request_queue *q, |
1506 | struct blk_mq_tag_set *set, | |
1507 | struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
1508 | { | |
f70ced09 ML |
1509 | unsigned flush_start_tag = set->queue_depth; |
1510 | ||
08e98fc6 ML |
1511 | blk_mq_tag_idle(hctx); |
1512 | ||
f70ced09 ML |
1513 | if (set->ops->exit_request) |
1514 | set->ops->exit_request(set->driver_data, | |
1515 | hctx->fq->flush_rq, hctx_idx, | |
1516 | flush_start_tag + hctx_idx); | |
1517 | ||
08e98fc6 ML |
1518 | if (set->ops->exit_hctx) |
1519 | set->ops->exit_hctx(hctx, hctx_idx); | |
1520 | ||
1521 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
f70ced09 | 1522 | blk_free_flush_queue(hctx->fq); |
08e98fc6 ML |
1523 | kfree(hctx->ctxs); |
1524 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1525 | } | |
1526 | ||
624dbe47 ML |
1527 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1528 | struct blk_mq_tag_set *set, int nr_queue) | |
1529 | { | |
1530 | struct blk_mq_hw_ctx *hctx; | |
1531 | unsigned int i; | |
1532 | ||
1533 | queue_for_each_hw_ctx(q, hctx, i) { | |
1534 | if (i == nr_queue) | |
1535 | break; | |
08e98fc6 | 1536 | blk_mq_exit_hctx(q, set, hctx, i); |
624dbe47 | 1537 | } |
624dbe47 ML |
1538 | } |
1539 | ||
1540 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1541 | struct blk_mq_tag_set *set) | |
1542 | { | |
1543 | struct blk_mq_hw_ctx *hctx; | |
1544 | unsigned int i; | |
1545 | ||
1546 | queue_for_each_hw_ctx(q, hctx, i) { | |
1547 | free_cpumask_var(hctx->cpumask); | |
cdef54dd | 1548 | kfree(hctx); |
624dbe47 ML |
1549 | } |
1550 | } | |
1551 | ||
08e98fc6 ML |
1552 | static int blk_mq_init_hctx(struct request_queue *q, |
1553 | struct blk_mq_tag_set *set, | |
1554 | struct blk_mq_hw_ctx *hctx, unsigned hctx_idx) | |
320ae51f | 1555 | { |
08e98fc6 | 1556 | int node; |
f70ced09 | 1557 | unsigned flush_start_tag = set->queue_depth; |
08e98fc6 ML |
1558 | |
1559 | node = hctx->numa_node; | |
1560 | if (node == NUMA_NO_NODE) | |
1561 | node = hctx->numa_node = set->numa_node; | |
1562 | ||
1563 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); | |
1564 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
1565 | spin_lock_init(&hctx->lock); | |
1566 | INIT_LIST_HEAD(&hctx->dispatch); | |
1567 | hctx->queue = q; | |
1568 | hctx->queue_num = hctx_idx; | |
1569 | hctx->flags = set->flags; | |
1570 | hctx->cmd_size = set->cmd_size; | |
1571 | ||
1572 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1573 | blk_mq_hctx_notify, hctx); | |
1574 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1575 | ||
1576 | hctx->tags = set->tags[hctx_idx]; | |
320ae51f JA |
1577 | |
1578 | /* | |
08e98fc6 ML |
1579 | * Allocate space for all possible cpus to avoid allocation at |
1580 | * runtime | |
320ae51f | 1581 | */ |
08e98fc6 ML |
1582 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), |
1583 | GFP_KERNEL, node); | |
1584 | if (!hctx->ctxs) | |
1585 | goto unregister_cpu_notifier; | |
320ae51f | 1586 | |
08e98fc6 ML |
1587 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
1588 | goto free_ctxs; | |
320ae51f | 1589 | |
08e98fc6 | 1590 | hctx->nr_ctx = 0; |
320ae51f | 1591 | |
08e98fc6 ML |
1592 | if (set->ops->init_hctx && |
1593 | set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) | |
1594 | goto free_bitmap; | |
320ae51f | 1595 | |
f70ced09 ML |
1596 | hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); |
1597 | if (!hctx->fq) | |
1598 | goto exit_hctx; | |
320ae51f | 1599 | |
f70ced09 ML |
1600 | if (set->ops->init_request && |
1601 | set->ops->init_request(set->driver_data, | |
1602 | hctx->fq->flush_rq, hctx_idx, | |
1603 | flush_start_tag + hctx_idx, node)) | |
1604 | goto free_fq; | |
320ae51f | 1605 | |
08e98fc6 | 1606 | return 0; |
320ae51f | 1607 | |
f70ced09 ML |
1608 | free_fq: |
1609 | kfree(hctx->fq); | |
1610 | exit_hctx: | |
1611 | if (set->ops->exit_hctx) | |
1612 | set->ops->exit_hctx(hctx, hctx_idx); | |
08e98fc6 ML |
1613 | free_bitmap: |
1614 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1615 | free_ctxs: | |
1616 | kfree(hctx->ctxs); | |
1617 | unregister_cpu_notifier: | |
1618 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
320ae51f | 1619 | |
08e98fc6 ML |
1620 | return -1; |
1621 | } | |
320ae51f | 1622 | |
08e98fc6 ML |
1623 | static int blk_mq_init_hw_queues(struct request_queue *q, |
1624 | struct blk_mq_tag_set *set) | |
1625 | { | |
1626 | struct blk_mq_hw_ctx *hctx; | |
1627 | unsigned int i; | |
320ae51f | 1628 | |
08e98fc6 ML |
1629 | /* |
1630 | * Initialize hardware queues | |
1631 | */ | |
1632 | queue_for_each_hw_ctx(q, hctx, i) { | |
1633 | if (blk_mq_init_hctx(q, set, hctx, i)) | |
320ae51f JA |
1634 | break; |
1635 | } | |
1636 | ||
1637 | if (i == q->nr_hw_queues) | |
1638 | return 0; | |
1639 | ||
1640 | /* | |
1641 | * Init failed | |
1642 | */ | |
624dbe47 | 1643 | blk_mq_exit_hw_queues(q, set, i); |
320ae51f JA |
1644 | |
1645 | return 1; | |
1646 | } | |
1647 | ||
1648 | static void blk_mq_init_cpu_queues(struct request_queue *q, | |
1649 | unsigned int nr_hw_queues) | |
1650 | { | |
1651 | unsigned int i; | |
1652 | ||
1653 | for_each_possible_cpu(i) { | |
1654 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1655 | struct blk_mq_hw_ctx *hctx; | |
1656 | ||
1657 | memset(__ctx, 0, sizeof(*__ctx)); | |
1658 | __ctx->cpu = i; | |
1659 | spin_lock_init(&__ctx->lock); | |
1660 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1661 | __ctx->queue = q; | |
1662 | ||
1663 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1664 | if (!cpu_online(i)) |
1665 | continue; | |
1666 | ||
e4043dcf JA |
1667 | hctx = q->mq_ops->map_queue(q, i); |
1668 | cpumask_set_cpu(i, hctx->cpumask); | |
1669 | hctx->nr_ctx++; | |
1670 | ||
320ae51f JA |
1671 | /* |
1672 | * Set local node, IFF we have more than one hw queue. If | |
1673 | * not, we remain on the home node of the device | |
1674 | */ | |
1675 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
1676 | hctx->numa_node = cpu_to_node(i); | |
1677 | } | |
1678 | } | |
1679 | ||
1680 | static void blk_mq_map_swqueue(struct request_queue *q) | |
1681 | { | |
1682 | unsigned int i; | |
1683 | struct blk_mq_hw_ctx *hctx; | |
1684 | struct blk_mq_ctx *ctx; | |
1685 | ||
1686 | queue_for_each_hw_ctx(q, hctx, i) { | |
e4043dcf | 1687 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1688 | hctx->nr_ctx = 0; |
1689 | } | |
1690 | ||
1691 | /* | |
1692 | * Map software to hardware queues | |
1693 | */ | |
1694 | queue_for_each_ctx(q, ctx, i) { | |
1695 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
e4043dcf JA |
1696 | if (!cpu_online(i)) |
1697 | continue; | |
1698 | ||
320ae51f | 1699 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1700 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1701 | ctx->index_hw = hctx->nr_ctx; |
1702 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1703 | } | |
506e931f JA |
1704 | |
1705 | queue_for_each_hw_ctx(q, hctx, i) { | |
484b4061 | 1706 | /* |
a68aafa5 JA |
1707 | * If no software queues are mapped to this hardware queue, |
1708 | * disable it and free the request entries. | |
484b4061 JA |
1709 | */ |
1710 | if (!hctx->nr_ctx) { | |
1711 | struct blk_mq_tag_set *set = q->tag_set; | |
1712 | ||
1713 | if (set->tags[i]) { | |
1714 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1715 | set->tags[i] = NULL; | |
1716 | hctx->tags = NULL; | |
1717 | } | |
1718 | continue; | |
1719 | } | |
1720 | ||
1721 | /* | |
1722 | * Initialize batch roundrobin counts | |
1723 | */ | |
506e931f JA |
1724 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1725 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1726 | } | |
320ae51f JA |
1727 | } |
1728 | ||
0d2602ca JA |
1729 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |
1730 | { | |
1731 | struct blk_mq_hw_ctx *hctx; | |
1732 | struct request_queue *q; | |
1733 | bool shared; | |
1734 | int i; | |
1735 | ||
1736 | if (set->tag_list.next == set->tag_list.prev) | |
1737 | shared = false; | |
1738 | else | |
1739 | shared = true; | |
1740 | ||
1741 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1742 | blk_mq_freeze_queue(q); | |
1743 | ||
1744 | queue_for_each_hw_ctx(q, hctx, i) { | |
1745 | if (shared) | |
1746 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1747 | else | |
1748 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1749 | } | |
1750 | blk_mq_unfreeze_queue(q); | |
1751 | } | |
1752 | } | |
1753 | ||
1754 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1755 | { | |
1756 | struct blk_mq_tag_set *set = q->tag_set; | |
1757 | ||
0d2602ca JA |
1758 | mutex_lock(&set->tag_list_lock); |
1759 | list_del_init(&q->tag_set_list); | |
1760 | blk_mq_update_tag_set_depth(set); | |
1761 | mutex_unlock(&set->tag_list_lock); | |
0d2602ca JA |
1762 | } |
1763 | ||
1764 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1765 | struct request_queue *q) | |
1766 | { | |
1767 | q->tag_set = set; | |
1768 | ||
1769 | mutex_lock(&set->tag_list_lock); | |
1770 | list_add_tail(&q->tag_set_list, &set->tag_list); | |
1771 | blk_mq_update_tag_set_depth(set); | |
1772 | mutex_unlock(&set->tag_list_lock); | |
1773 | } | |
1774 | ||
24d2f903 | 1775 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
320ae51f JA |
1776 | { |
1777 | struct blk_mq_hw_ctx **hctxs; | |
e6cdb092 | 1778 | struct blk_mq_ctx __percpu *ctx; |
320ae51f | 1779 | struct request_queue *q; |
f14bbe77 | 1780 | unsigned int *map; |
320ae51f JA |
1781 | int i; |
1782 | ||
320ae51f JA |
1783 | ctx = alloc_percpu(struct blk_mq_ctx); |
1784 | if (!ctx) | |
1785 | return ERR_PTR(-ENOMEM); | |
1786 | ||
aedcd72f JA |
1787 | /* |
1788 | * If a crashdump is active, then we are potentially in a very | |
1789 | * memory constrained environment. Limit us to 1 queue and | |
1790 | * 64 tags to prevent using too much memory. | |
1791 | */ | |
1792 | if (is_kdump_kernel()) { | |
1793 | set->nr_hw_queues = 1; | |
1794 | set->queue_depth = min(64U, set->queue_depth); | |
1795 | } | |
1796 | ||
24d2f903 CH |
1797 | hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, |
1798 | set->numa_node); | |
320ae51f JA |
1799 | |
1800 | if (!hctxs) | |
1801 | goto err_percpu; | |
1802 | ||
f14bbe77 JA |
1803 | map = blk_mq_make_queue_map(set); |
1804 | if (!map) | |
1805 | goto err_map; | |
1806 | ||
24d2f903 | 1807 | for (i = 0; i < set->nr_hw_queues; i++) { |
f14bbe77 JA |
1808 | int node = blk_mq_hw_queue_to_node(map, i); |
1809 | ||
cdef54dd CH |
1810 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1811 | GFP_KERNEL, node); | |
320ae51f JA |
1812 | if (!hctxs[i]) |
1813 | goto err_hctxs; | |
1814 | ||
a86073e4 JA |
1815 | if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, |
1816 | node)) | |
e4043dcf JA |
1817 | goto err_hctxs; |
1818 | ||
0d2602ca | 1819 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1820 | hctxs[i]->numa_node = node; |
320ae51f JA |
1821 | hctxs[i]->queue_num = i; |
1822 | } | |
1823 | ||
24d2f903 | 1824 | q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); |
320ae51f JA |
1825 | if (!q) |
1826 | goto err_hctxs; | |
1827 | ||
17497acb TH |
1828 | /* |
1829 | * Init percpu_ref in atomic mode so that it's faster to shutdown. | |
1830 | * See blk_register_queue() for details. | |
1831 | */ | |
a34375ef | 1832 | if (percpu_ref_init(&q->mq_usage_counter, blk_mq_usage_counter_release, |
17497acb | 1833 | PERCPU_REF_INIT_ATOMIC, GFP_KERNEL)) |
3d2936f4 ML |
1834 | goto err_map; |
1835 | ||
320ae51f JA |
1836 | setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); |
1837 | blk_queue_rq_timeout(q, 30000); | |
1838 | ||
1839 | q->nr_queues = nr_cpu_ids; | |
24d2f903 | 1840 | q->nr_hw_queues = set->nr_hw_queues; |
f14bbe77 | 1841 | q->mq_map = map; |
320ae51f JA |
1842 | |
1843 | q->queue_ctx = ctx; | |
1844 | q->queue_hw_ctx = hctxs; | |
1845 | ||
24d2f903 | 1846 | q->mq_ops = set->ops; |
94eddfbe | 1847 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 1848 | |
05f1dd53 JA |
1849 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
1850 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
1851 | ||
1be036e9 CH |
1852 | q->sg_reserved_size = INT_MAX; |
1853 | ||
6fca6a61 CH |
1854 | INIT_WORK(&q->requeue_work, blk_mq_requeue_work); |
1855 | INIT_LIST_HEAD(&q->requeue_list); | |
1856 | spin_lock_init(&q->requeue_lock); | |
1857 | ||
07068d5b JA |
1858 | if (q->nr_hw_queues > 1) |
1859 | blk_queue_make_request(q, blk_mq_make_request); | |
1860 | else | |
1861 | blk_queue_make_request(q, blk_sq_make_request); | |
1862 | ||
24d2f903 CH |
1863 | if (set->timeout) |
1864 | blk_queue_rq_timeout(q, set->timeout); | |
320ae51f | 1865 | |
eba71768 JA |
1866 | /* |
1867 | * Do this after blk_queue_make_request() overrides it... | |
1868 | */ | |
1869 | q->nr_requests = set->queue_depth; | |
1870 | ||
24d2f903 CH |
1871 | if (set->ops->complete) |
1872 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 1873 | |
24d2f903 | 1874 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 1875 | |
24d2f903 | 1876 | if (blk_mq_init_hw_queues(q, set)) |
1bcb1ead | 1877 | goto err_hw; |
18741986 | 1878 | |
320ae51f JA |
1879 | mutex_lock(&all_q_mutex); |
1880 | list_add_tail(&q->all_q_node, &all_q_list); | |
1881 | mutex_unlock(&all_q_mutex); | |
1882 | ||
0d2602ca JA |
1883 | blk_mq_add_queue_tag_set(set, q); |
1884 | ||
484b4061 JA |
1885 | blk_mq_map_swqueue(q); |
1886 | ||
320ae51f | 1887 | return q; |
18741986 | 1888 | |
320ae51f | 1889 | err_hw: |
320ae51f JA |
1890 | blk_cleanup_queue(q); |
1891 | err_hctxs: | |
f14bbe77 | 1892 | kfree(map); |
24d2f903 | 1893 | for (i = 0; i < set->nr_hw_queues; i++) { |
320ae51f JA |
1894 | if (!hctxs[i]) |
1895 | break; | |
e4043dcf | 1896 | free_cpumask_var(hctxs[i]->cpumask); |
cdef54dd | 1897 | kfree(hctxs[i]); |
320ae51f | 1898 | } |
f14bbe77 | 1899 | err_map: |
320ae51f JA |
1900 | kfree(hctxs); |
1901 | err_percpu: | |
1902 | free_percpu(ctx); | |
1903 | return ERR_PTR(-ENOMEM); | |
1904 | } | |
1905 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1906 | ||
1907 | void blk_mq_free_queue(struct request_queue *q) | |
1908 | { | |
624dbe47 | 1909 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 1910 | |
0d2602ca JA |
1911 | blk_mq_del_queue_tag_set(q); |
1912 | ||
624dbe47 ML |
1913 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
1914 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 1915 | |
add703fd | 1916 | percpu_ref_exit(&q->mq_usage_counter); |
3d2936f4 | 1917 | |
320ae51f JA |
1918 | free_percpu(q->queue_ctx); |
1919 | kfree(q->queue_hw_ctx); | |
1920 | kfree(q->mq_map); | |
1921 | ||
1922 | q->queue_ctx = NULL; | |
1923 | q->queue_hw_ctx = NULL; | |
1924 | q->mq_map = NULL; | |
1925 | ||
1926 | mutex_lock(&all_q_mutex); | |
1927 | list_del_init(&q->all_q_node); | |
1928 | mutex_unlock(&all_q_mutex); | |
1929 | } | |
320ae51f JA |
1930 | |
1931 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
f618ef7c | 1932 | static void blk_mq_queue_reinit(struct request_queue *q) |
320ae51f | 1933 | { |
f3af020b | 1934 | WARN_ON_ONCE(!q->mq_freeze_depth); |
320ae51f | 1935 | |
67aec14c JA |
1936 | blk_mq_sysfs_unregister(q); |
1937 | ||
320ae51f JA |
1938 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues); |
1939 | ||
1940 | /* | |
1941 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
1942 | * we should change hctx numa_node according to new topology (this | |
1943 | * involves free and re-allocate memory, worthy doing?) | |
1944 | */ | |
1945 | ||
1946 | blk_mq_map_swqueue(q); | |
1947 | ||
67aec14c | 1948 | blk_mq_sysfs_register(q); |
320ae51f JA |
1949 | } |
1950 | ||
f618ef7c PG |
1951 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
1952 | unsigned long action, void *hcpu) | |
320ae51f JA |
1953 | { |
1954 | struct request_queue *q; | |
1955 | ||
1956 | /* | |
9fccfed8 JA |
1957 | * Before new mappings are established, hotadded cpu might already |
1958 | * start handling requests. This doesn't break anything as we map | |
1959 | * offline CPUs to first hardware queue. We will re-init the queue | |
1960 | * below to get optimal settings. | |
320ae51f JA |
1961 | */ |
1962 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN && | |
1963 | action != CPU_ONLINE && action != CPU_ONLINE_FROZEN) | |
1964 | return NOTIFY_OK; | |
1965 | ||
1966 | mutex_lock(&all_q_mutex); | |
f3af020b TH |
1967 | |
1968 | /* | |
1969 | * We need to freeze and reinit all existing queues. Freezing | |
1970 | * involves synchronous wait for an RCU grace period and doing it | |
1971 | * one by one may take a long time. Start freezing all queues in | |
1972 | * one swoop and then wait for the completions so that freezing can | |
1973 | * take place in parallel. | |
1974 | */ | |
1975 | list_for_each_entry(q, &all_q_list, all_q_node) | |
1976 | blk_mq_freeze_queue_start(q); | |
1977 | list_for_each_entry(q, &all_q_list, all_q_node) | |
1978 | blk_mq_freeze_queue_wait(q); | |
1979 | ||
320ae51f JA |
1980 | list_for_each_entry(q, &all_q_list, all_q_node) |
1981 | blk_mq_queue_reinit(q); | |
f3af020b TH |
1982 | |
1983 | list_for_each_entry(q, &all_q_list, all_q_node) | |
1984 | blk_mq_unfreeze_queue(q); | |
1985 | ||
320ae51f JA |
1986 | mutex_unlock(&all_q_mutex); |
1987 | return NOTIFY_OK; | |
1988 | } | |
1989 | ||
a5164405 JA |
1990 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
1991 | { | |
1992 | int i; | |
1993 | ||
1994 | for (i = 0; i < set->nr_hw_queues; i++) { | |
1995 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1996 | if (!set->tags[i]) | |
1997 | goto out_unwind; | |
1998 | } | |
1999 | ||
2000 | return 0; | |
2001 | ||
2002 | out_unwind: | |
2003 | while (--i >= 0) | |
2004 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2005 | ||
a5164405 JA |
2006 | return -ENOMEM; |
2007 | } | |
2008 | ||
2009 | /* | |
2010 | * Allocate the request maps associated with this tag_set. Note that this | |
2011 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
2012 | * will be updated to reflect the allocated depth. | |
2013 | */ | |
2014 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
2015 | { | |
2016 | unsigned int depth; | |
2017 | int err; | |
2018 | ||
2019 | depth = set->queue_depth; | |
2020 | do { | |
2021 | err = __blk_mq_alloc_rq_maps(set); | |
2022 | if (!err) | |
2023 | break; | |
2024 | ||
2025 | set->queue_depth >>= 1; | |
2026 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
2027 | err = -ENOMEM; | |
2028 | break; | |
2029 | } | |
2030 | } while (set->queue_depth); | |
2031 | ||
2032 | if (!set->queue_depth || err) { | |
2033 | pr_err("blk-mq: failed to allocate request map\n"); | |
2034 | return -ENOMEM; | |
2035 | } | |
2036 | ||
2037 | if (depth != set->queue_depth) | |
2038 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2039 | depth, set->queue_depth); | |
2040 | ||
2041 | return 0; | |
2042 | } | |
2043 | ||
a4391c64 JA |
2044 | /* |
2045 | * Alloc a tag set to be associated with one or more request queues. | |
2046 | * May fail with EINVAL for various error conditions. May adjust the | |
2047 | * requested depth down, if if it too large. In that case, the set | |
2048 | * value will be stored in set->queue_depth. | |
2049 | */ | |
24d2f903 CH |
2050 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2051 | { | |
205fb5f5 BVA |
2052 | BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS); |
2053 | ||
24d2f903 CH |
2054 | if (!set->nr_hw_queues) |
2055 | return -EINVAL; | |
a4391c64 | 2056 | if (!set->queue_depth) |
24d2f903 CH |
2057 | return -EINVAL; |
2058 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2059 | return -EINVAL; | |
2060 | ||
cdef54dd | 2061 | if (!set->nr_hw_queues || !set->ops->queue_rq || !set->ops->map_queue) |
24d2f903 CH |
2062 | return -EINVAL; |
2063 | ||
a4391c64 JA |
2064 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2065 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2066 | BLK_MQ_MAX_DEPTH); | |
2067 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2068 | } | |
24d2f903 | 2069 | |
48479005 ML |
2070 | set->tags = kmalloc_node(set->nr_hw_queues * |
2071 | sizeof(struct blk_mq_tags *), | |
24d2f903 CH |
2072 | GFP_KERNEL, set->numa_node); |
2073 | if (!set->tags) | |
a5164405 | 2074 | return -ENOMEM; |
24d2f903 | 2075 | |
a5164405 JA |
2076 | if (blk_mq_alloc_rq_maps(set)) |
2077 | goto enomem; | |
24d2f903 | 2078 | |
0d2602ca JA |
2079 | mutex_init(&set->tag_list_lock); |
2080 | INIT_LIST_HEAD(&set->tag_list); | |
2081 | ||
24d2f903 | 2082 | return 0; |
a5164405 | 2083 | enomem: |
5676e7b6 RE |
2084 | kfree(set->tags); |
2085 | set->tags = NULL; | |
24d2f903 CH |
2086 | return -ENOMEM; |
2087 | } | |
2088 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2089 | ||
2090 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2091 | { | |
2092 | int i; | |
2093 | ||
484b4061 JA |
2094 | for (i = 0; i < set->nr_hw_queues; i++) { |
2095 | if (set->tags[i]) | |
2096 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2097 | } | |
2098 | ||
981bd189 | 2099 | kfree(set->tags); |
5676e7b6 | 2100 | set->tags = NULL; |
24d2f903 CH |
2101 | } |
2102 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2103 | ||
e3a2b3f9 JA |
2104 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2105 | { | |
2106 | struct blk_mq_tag_set *set = q->tag_set; | |
2107 | struct blk_mq_hw_ctx *hctx; | |
2108 | int i, ret; | |
2109 | ||
2110 | if (!set || nr > set->queue_depth) | |
2111 | return -EINVAL; | |
2112 | ||
2113 | ret = 0; | |
2114 | queue_for_each_hw_ctx(q, hctx, i) { | |
2115 | ret = blk_mq_tag_update_depth(hctx->tags, nr); | |
2116 | if (ret) | |
2117 | break; | |
2118 | } | |
2119 | ||
2120 | if (!ret) | |
2121 | q->nr_requests = nr; | |
2122 | ||
2123 | return ret; | |
2124 | } | |
2125 | ||
676141e4 JA |
2126 | void blk_mq_disable_hotplug(void) |
2127 | { | |
2128 | mutex_lock(&all_q_mutex); | |
2129 | } | |
2130 | ||
2131 | void blk_mq_enable_hotplug(void) | |
2132 | { | |
2133 | mutex_unlock(&all_q_mutex); | |
2134 | } | |
2135 | ||
320ae51f JA |
2136 | static int __init blk_mq_init(void) |
2137 | { | |
320ae51f JA |
2138 | blk_mq_cpu_init(); |
2139 | ||
add703fd | 2140 | hotcpu_notifier(blk_mq_queue_reinit_notify, 0); |
320ae51f JA |
2141 | |
2142 | return 0; | |
2143 | } | |
2144 | subsys_initcall(blk_mq_init); |