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> | |
23 | ||
24 | #include <trace/events/block.h> | |
25 | ||
26 | #include <linux/blk-mq.h> | |
27 | #include "blk.h" | |
28 | #include "blk-mq.h" | |
29 | #include "blk-mq-tag.h" | |
30 | ||
31 | static DEFINE_MUTEX(all_q_mutex); | |
32 | static LIST_HEAD(all_q_list); | |
33 | ||
34 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx); | |
35 | ||
320ae51f JA |
36 | /* |
37 | * Check if any of the ctx's have pending work in this hardware queue | |
38 | */ | |
39 | static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx) | |
40 | { | |
41 | unsigned int i; | |
42 | ||
1429d7c9 JA |
43 | for (i = 0; i < hctx->ctx_map.map_size; i++) |
44 | if (hctx->ctx_map.map[i].word) | |
320ae51f JA |
45 | return true; |
46 | ||
47 | return false; | |
48 | } | |
49 | ||
1429d7c9 JA |
50 | static inline struct blk_align_bitmap *get_bm(struct blk_mq_hw_ctx *hctx, |
51 | struct blk_mq_ctx *ctx) | |
52 | { | |
53 | return &hctx->ctx_map.map[ctx->index_hw / hctx->ctx_map.bits_per_word]; | |
54 | } | |
55 | ||
56 | #define CTX_TO_BIT(hctx, ctx) \ | |
57 | ((ctx)->index_hw & ((hctx)->ctx_map.bits_per_word - 1)) | |
58 | ||
320ae51f JA |
59 | /* |
60 | * Mark this ctx as having pending work in this hardware queue | |
61 | */ | |
62 | static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, | |
63 | struct blk_mq_ctx *ctx) | |
64 | { | |
1429d7c9 JA |
65 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); |
66 | ||
67 | if (!test_bit(CTX_TO_BIT(hctx, ctx), &bm->word)) | |
68 | set_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
69 | } | |
70 | ||
71 | static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, | |
72 | struct blk_mq_ctx *ctx) | |
73 | { | |
74 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); | |
75 | ||
76 | clear_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
320ae51f JA |
77 | } |
78 | ||
320ae51f JA |
79 | static int blk_mq_queue_enter(struct request_queue *q) |
80 | { | |
add703fd TH |
81 | while (true) { |
82 | int ret; | |
320ae51f | 83 | |
add703fd TH |
84 | if (percpu_ref_tryget_live(&q->mq_usage_counter)) |
85 | return 0; | |
320ae51f | 86 | |
add703fd TH |
87 | ret = wait_event_interruptible(q->mq_freeze_wq, |
88 | !q->mq_freeze_depth || blk_queue_dying(q)); | |
89 | if (blk_queue_dying(q)) | |
90 | return -ENODEV; | |
91 | if (ret) | |
92 | return ret; | |
93 | } | |
320ae51f JA |
94 | } |
95 | ||
96 | static void blk_mq_queue_exit(struct request_queue *q) | |
97 | { | |
add703fd TH |
98 | percpu_ref_put(&q->mq_usage_counter); |
99 | } | |
100 | ||
101 | static void blk_mq_usage_counter_release(struct percpu_ref *ref) | |
102 | { | |
103 | struct request_queue *q = | |
104 | container_of(ref, struct request_queue, mq_usage_counter); | |
105 | ||
106 | wake_up_all(&q->mq_freeze_wq); | |
320ae51f JA |
107 | } |
108 | ||
72d6f02a TH |
109 | /* |
110 | * Guarantee no request is in use, so we can change any data structure of | |
111 | * the queue afterward. | |
112 | */ | |
113 | void blk_mq_freeze_queue(struct request_queue *q) | |
43a5e4e2 | 114 | { |
cddd5d17 TH |
115 | bool freeze; |
116 | ||
72d6f02a | 117 | spin_lock_irq(q->queue_lock); |
cddd5d17 | 118 | freeze = !q->mq_freeze_depth++; |
72d6f02a TH |
119 | spin_unlock_irq(q->queue_lock); |
120 | ||
cddd5d17 | 121 | if (freeze) { |
0a30288d TH |
122 | /* |
123 | * XXX: Temporary kludge to work around SCSI blk-mq stall. | |
124 | * SCSI synchronously creates and destroys many queues | |
125 | * back-to-back during probe leading to lengthy stalls. | |
126 | * This will be fixed by keeping ->mq_usage_counter in | |
127 | * atomic mode until genhd registration, but, for now, | |
128 | * let's work around using expedited synchronization. | |
129 | */ | |
130 | __percpu_ref_kill_expedited(&q->mq_usage_counter); | |
131 | ||
cddd5d17 TH |
132 | blk_mq_run_queues(q, false); |
133 | } | |
add703fd | 134 | wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); |
43a5e4e2 ML |
135 | } |
136 | ||
320ae51f JA |
137 | static void blk_mq_unfreeze_queue(struct request_queue *q) |
138 | { | |
cddd5d17 | 139 | bool wake; |
320ae51f JA |
140 | |
141 | spin_lock_irq(q->queue_lock); | |
780db207 TH |
142 | wake = !--q->mq_freeze_depth; |
143 | WARN_ON_ONCE(q->mq_freeze_depth < 0); | |
320ae51f | 144 | spin_unlock_irq(q->queue_lock); |
add703fd TH |
145 | if (wake) { |
146 | percpu_ref_reinit(&q->mq_usage_counter); | |
320ae51f | 147 | wake_up_all(&q->mq_freeze_wq); |
add703fd | 148 | } |
320ae51f JA |
149 | } |
150 | ||
151 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) | |
152 | { | |
153 | return blk_mq_has_free_tags(hctx->tags); | |
154 | } | |
155 | EXPORT_SYMBOL(blk_mq_can_queue); | |
156 | ||
94eddfbe JA |
157 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
158 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 159 | { |
94eddfbe JA |
160 | if (blk_queue_io_stat(q)) |
161 | rw_flags |= REQ_IO_STAT; | |
162 | ||
af76e555 CH |
163 | INIT_LIST_HEAD(&rq->queuelist); |
164 | /* csd/requeue_work/fifo_time is initialized before use */ | |
165 | rq->q = q; | |
320ae51f | 166 | rq->mq_ctx = ctx; |
0d2602ca | 167 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
168 | /* do not touch atomic flags, it needs atomic ops against the timer */ |
169 | rq->cpu = -1; | |
af76e555 CH |
170 | INIT_HLIST_NODE(&rq->hash); |
171 | RB_CLEAR_NODE(&rq->rb_node); | |
af76e555 CH |
172 | rq->rq_disk = NULL; |
173 | rq->part = NULL; | |
3ee32372 | 174 | rq->start_time = jiffies; |
af76e555 CH |
175 | #ifdef CONFIG_BLK_CGROUP |
176 | rq->rl = NULL; | |
0fec08b4 | 177 | set_start_time_ns(rq); |
af76e555 CH |
178 | rq->io_start_time_ns = 0; |
179 | #endif | |
180 | rq->nr_phys_segments = 0; | |
181 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
182 | rq->nr_integrity_segments = 0; | |
183 | #endif | |
af76e555 CH |
184 | rq->special = NULL; |
185 | /* tag was already set */ | |
186 | rq->errors = 0; | |
af76e555 | 187 | |
6f4a1626 TB |
188 | rq->cmd = rq->__cmd; |
189 | ||
af76e555 CH |
190 | rq->extra_len = 0; |
191 | rq->sense_len = 0; | |
192 | rq->resid_len = 0; | |
193 | rq->sense = NULL; | |
194 | ||
af76e555 | 195 | INIT_LIST_HEAD(&rq->timeout_list); |
f6be4fb4 JA |
196 | rq->timeout = 0; |
197 | ||
af76e555 CH |
198 | rq->end_io = NULL; |
199 | rq->end_io_data = NULL; | |
200 | rq->next_rq = NULL; | |
201 | ||
320ae51f JA |
202 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
203 | } | |
204 | ||
5dee8577 | 205 | static struct request * |
cb96a42c | 206 | __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) |
5dee8577 CH |
207 | { |
208 | struct request *rq; | |
209 | unsigned int tag; | |
210 | ||
cb96a42c | 211 | tag = blk_mq_get_tag(data); |
5dee8577 | 212 | if (tag != BLK_MQ_TAG_FAIL) { |
cb96a42c | 213 | rq = data->hctx->tags->rqs[tag]; |
5dee8577 | 214 | |
cb96a42c | 215 | if (blk_mq_tag_busy(data->hctx)) { |
5dee8577 | 216 | rq->cmd_flags = REQ_MQ_INFLIGHT; |
cb96a42c | 217 | atomic_inc(&data->hctx->nr_active); |
5dee8577 CH |
218 | } |
219 | ||
220 | rq->tag = tag; | |
cb96a42c | 221 | blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); |
5dee8577 CH |
222 | return rq; |
223 | } | |
224 | ||
225 | return NULL; | |
226 | } | |
227 | ||
4ce01dd1 CH |
228 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp, |
229 | bool reserved) | |
320ae51f | 230 | { |
d852564f CH |
231 | struct blk_mq_ctx *ctx; |
232 | struct blk_mq_hw_ctx *hctx; | |
320ae51f | 233 | struct request *rq; |
cb96a42c | 234 | struct blk_mq_alloc_data alloc_data; |
320ae51f JA |
235 | |
236 | if (blk_mq_queue_enter(q)) | |
237 | return NULL; | |
238 | ||
d852564f CH |
239 | ctx = blk_mq_get_ctx(q); |
240 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
241 | blk_mq_set_alloc_data(&alloc_data, q, gfp & ~__GFP_WAIT, |
242 | reserved, ctx, hctx); | |
d852564f | 243 | |
cb96a42c | 244 | rq = __blk_mq_alloc_request(&alloc_data, rw); |
d852564f CH |
245 | if (!rq && (gfp & __GFP_WAIT)) { |
246 | __blk_mq_run_hw_queue(hctx); | |
247 | blk_mq_put_ctx(ctx); | |
248 | ||
249 | ctx = blk_mq_get_ctx(q); | |
250 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
cb96a42c ML |
251 | blk_mq_set_alloc_data(&alloc_data, q, gfp, reserved, ctx, |
252 | hctx); | |
253 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
254 | ctx = alloc_data.ctx; | |
d852564f CH |
255 | } |
256 | blk_mq_put_ctx(ctx); | |
320ae51f JA |
257 | return rq; |
258 | } | |
4bb659b1 | 259 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f | 260 | |
320ae51f JA |
261 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
262 | struct blk_mq_ctx *ctx, struct request *rq) | |
263 | { | |
264 | const int tag = rq->tag; | |
265 | struct request_queue *q = rq->q; | |
266 | ||
0d2602ca JA |
267 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
268 | atomic_dec(&hctx->nr_active); | |
683d0e12 | 269 | rq->cmd_flags = 0; |
0d2602ca | 270 | |
af76e555 | 271 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 272 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
320ae51f JA |
273 | blk_mq_queue_exit(q); |
274 | } | |
275 | ||
276 | void blk_mq_free_request(struct request *rq) | |
277 | { | |
278 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
279 | struct blk_mq_hw_ctx *hctx; | |
280 | struct request_queue *q = rq->q; | |
281 | ||
282 | ctx->rq_completed[rq_is_sync(rq)]++; | |
283 | ||
284 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
285 | __blk_mq_free_request(hctx, ctx, rq); | |
286 | } | |
287 | ||
8727af4b CH |
288 | /* |
289 | * Clone all relevant state from a request that has been put on hold in | |
290 | * the flush state machine into the preallocated flush request that hangs | |
291 | * off the request queue. | |
292 | * | |
293 | * For a driver the flush request should be invisible, that's why we are | |
294 | * impersonating the original request here. | |
295 | */ | |
296 | void blk_mq_clone_flush_request(struct request *flush_rq, | |
297 | struct request *orig_rq) | |
298 | { | |
299 | struct blk_mq_hw_ctx *hctx = | |
300 | orig_rq->q->mq_ops->map_queue(orig_rq->q, orig_rq->mq_ctx->cpu); | |
301 | ||
302 | flush_rq->mq_ctx = orig_rq->mq_ctx; | |
303 | flush_rq->tag = orig_rq->tag; | |
304 | memcpy(blk_mq_rq_to_pdu(flush_rq), blk_mq_rq_to_pdu(orig_rq), | |
305 | hctx->cmd_size); | |
306 | } | |
307 | ||
63151a44 | 308 | inline void __blk_mq_end_io(struct request *rq, int error) |
320ae51f | 309 | { |
0d11e6ac ML |
310 | blk_account_io_done(rq); |
311 | ||
91b63639 | 312 | if (rq->end_io) { |
320ae51f | 313 | rq->end_io(rq, error); |
91b63639 CH |
314 | } else { |
315 | if (unlikely(blk_bidi_rq(rq))) | |
316 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 317 | blk_mq_free_request(rq); |
91b63639 | 318 | } |
320ae51f | 319 | } |
63151a44 CH |
320 | EXPORT_SYMBOL(__blk_mq_end_io); |
321 | ||
322 | void blk_mq_end_io(struct request *rq, int error) | |
323 | { | |
324 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
325 | BUG(); | |
326 | __blk_mq_end_io(rq, error); | |
327 | } | |
328 | EXPORT_SYMBOL(blk_mq_end_io); | |
320ae51f | 329 | |
30a91cb4 | 330 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 331 | { |
3d6efbf6 | 332 | struct request *rq = data; |
320ae51f | 333 | |
30a91cb4 | 334 | rq->q->softirq_done_fn(rq); |
320ae51f | 335 | } |
320ae51f | 336 | |
ed851860 | 337 | static void blk_mq_ipi_complete_request(struct request *rq) |
320ae51f JA |
338 | { |
339 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 340 | bool shared = false; |
320ae51f JA |
341 | int cpu; |
342 | ||
38535201 | 343 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
344 | rq->q->softirq_done_fn(rq); |
345 | return; | |
346 | } | |
320ae51f JA |
347 | |
348 | cpu = get_cpu(); | |
38535201 CH |
349 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
350 | shared = cpus_share_cache(cpu, ctx->cpu); | |
351 | ||
352 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 353 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
354 | rq->csd.info = rq; |
355 | rq->csd.flags = 0; | |
c46fff2a | 356 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 357 | } else { |
30a91cb4 | 358 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 359 | } |
320ae51f JA |
360 | put_cpu(); |
361 | } | |
30a91cb4 | 362 | |
ed851860 JA |
363 | void __blk_mq_complete_request(struct request *rq) |
364 | { | |
365 | struct request_queue *q = rq->q; | |
366 | ||
367 | if (!q->softirq_done_fn) | |
368 | blk_mq_end_io(rq, rq->errors); | |
369 | else | |
370 | blk_mq_ipi_complete_request(rq); | |
371 | } | |
372 | ||
30a91cb4 CH |
373 | /** |
374 | * blk_mq_complete_request - end I/O on a request | |
375 | * @rq: the request being processed | |
376 | * | |
377 | * Description: | |
378 | * Ends all I/O on a request. It does not handle partial completions. | |
379 | * The actual completion happens out-of-order, through a IPI handler. | |
380 | **/ | |
381 | void blk_mq_complete_request(struct request *rq) | |
382 | { | |
95f09684 JA |
383 | struct request_queue *q = rq->q; |
384 | ||
385 | if (unlikely(blk_should_fake_timeout(q))) | |
30a91cb4 | 386 | return; |
ed851860 JA |
387 | if (!blk_mark_rq_complete(rq)) |
388 | __blk_mq_complete_request(rq); | |
30a91cb4 CH |
389 | } |
390 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 391 | |
49f5baa5 | 392 | static void blk_mq_start_request(struct request *rq, bool last) |
320ae51f JA |
393 | { |
394 | struct request_queue *q = rq->q; | |
395 | ||
396 | trace_block_rq_issue(q, rq); | |
397 | ||
742ee69b | 398 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
399 | if (unlikely(blk_bidi_rq(rq))) |
400 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 401 | |
2b8393b4 | 402 | blk_add_timer(rq); |
87ee7b11 | 403 | |
538b7534 JA |
404 | /* |
405 | * Ensure that ->deadline is visible before set the started | |
406 | * flag and clear the completed flag. | |
407 | */ | |
408 | smp_mb__before_atomic(); | |
409 | ||
87ee7b11 JA |
410 | /* |
411 | * Mark us as started and clear complete. Complete might have been | |
412 | * set if requeue raced with timeout, which then marked it as | |
413 | * complete. So be sure to clear complete again when we start | |
414 | * the request, otherwise we'll ignore the completion event. | |
415 | */ | |
4b570521 JA |
416 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
417 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
418 | if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) | |
419 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); | |
49f5baa5 CH |
420 | |
421 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
422 | /* | |
423 | * Make sure space for the drain appears. We know we can do | |
424 | * this because max_hw_segments has been adjusted to be one | |
425 | * fewer than the device can handle. | |
426 | */ | |
427 | rq->nr_phys_segments++; | |
428 | } | |
429 | ||
430 | /* | |
431 | * Flag the last request in the series so that drivers know when IO | |
432 | * should be kicked off, if they don't do it on a per-request basis. | |
433 | * | |
434 | * Note: the flag isn't the only condition drivers should do kick off. | |
435 | * If drive is busy, the last request might not have the bit set. | |
436 | */ | |
437 | if (last) | |
438 | rq->cmd_flags |= REQ_END; | |
320ae51f JA |
439 | } |
440 | ||
ed0791b2 | 441 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
442 | { |
443 | struct request_queue *q = rq->q; | |
444 | ||
445 | trace_block_rq_requeue(q, rq); | |
446 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
49f5baa5 CH |
447 | |
448 | rq->cmd_flags &= ~REQ_END; | |
449 | ||
450 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
451 | rq->nr_phys_segments--; | |
320ae51f JA |
452 | } |
453 | ||
ed0791b2 CH |
454 | void blk_mq_requeue_request(struct request *rq) |
455 | { | |
ed0791b2 CH |
456 | __blk_mq_requeue_request(rq); |
457 | blk_clear_rq_complete(rq); | |
458 | ||
ed0791b2 | 459 | BUG_ON(blk_queued_rq(rq)); |
6fca6a61 | 460 | blk_mq_add_to_requeue_list(rq, true); |
ed0791b2 CH |
461 | } |
462 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
463 | ||
6fca6a61 CH |
464 | static void blk_mq_requeue_work(struct work_struct *work) |
465 | { | |
466 | struct request_queue *q = | |
467 | container_of(work, struct request_queue, requeue_work); | |
468 | LIST_HEAD(rq_list); | |
469 | struct request *rq, *next; | |
470 | unsigned long flags; | |
471 | ||
472 | spin_lock_irqsave(&q->requeue_lock, flags); | |
473 | list_splice_init(&q->requeue_list, &rq_list); | |
474 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
475 | ||
476 | list_for_each_entry_safe(rq, next, &rq_list, queuelist) { | |
477 | if (!(rq->cmd_flags & REQ_SOFTBARRIER)) | |
478 | continue; | |
479 | ||
480 | rq->cmd_flags &= ~REQ_SOFTBARRIER; | |
481 | list_del_init(&rq->queuelist); | |
482 | blk_mq_insert_request(rq, true, false, false); | |
483 | } | |
484 | ||
485 | while (!list_empty(&rq_list)) { | |
486 | rq = list_entry(rq_list.next, struct request, queuelist); | |
487 | list_del_init(&rq->queuelist); | |
488 | blk_mq_insert_request(rq, false, false, false); | |
489 | } | |
490 | ||
8b957415 JA |
491 | /* |
492 | * Use the start variant of queue running here, so that running | |
493 | * the requeue work will kick stopped queues. | |
494 | */ | |
495 | blk_mq_start_hw_queues(q); | |
6fca6a61 CH |
496 | } |
497 | ||
498 | void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) | |
499 | { | |
500 | struct request_queue *q = rq->q; | |
501 | unsigned long flags; | |
502 | ||
503 | /* | |
504 | * We abuse this flag that is otherwise used by the I/O scheduler to | |
505 | * request head insertation from the workqueue. | |
506 | */ | |
507 | BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); | |
508 | ||
509 | spin_lock_irqsave(&q->requeue_lock, flags); | |
510 | if (at_head) { | |
511 | rq->cmd_flags |= REQ_SOFTBARRIER; | |
512 | list_add(&rq->queuelist, &q->requeue_list); | |
513 | } else { | |
514 | list_add_tail(&rq->queuelist, &q->requeue_list); | |
515 | } | |
516 | spin_unlock_irqrestore(&q->requeue_lock, flags); | |
517 | } | |
518 | EXPORT_SYMBOL(blk_mq_add_to_requeue_list); | |
519 | ||
520 | void blk_mq_kick_requeue_list(struct request_queue *q) | |
521 | { | |
522 | kblockd_schedule_work(&q->requeue_work); | |
523 | } | |
524 | EXPORT_SYMBOL(blk_mq_kick_requeue_list); | |
525 | ||
0e62f51f | 526 | static inline bool is_flush_request(struct request *rq, unsigned int tag) |
24d2f903 | 527 | { |
0e62f51f JA |
528 | return ((rq->cmd_flags & REQ_FLUSH_SEQ) && |
529 | rq->q->flush_rq->tag == tag); | |
530 | } | |
531 | ||
532 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) | |
533 | { | |
534 | struct request *rq = tags->rqs[tag]; | |
22302375 | 535 | |
0e62f51f JA |
536 | if (!is_flush_request(rq, tag)) |
537 | return rq; | |
22302375 | 538 | |
0e62f51f | 539 | return rq->q->flush_rq; |
24d2f903 CH |
540 | } |
541 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
542 | ||
320ae51f JA |
543 | struct blk_mq_timeout_data { |
544 | struct blk_mq_hw_ctx *hctx; | |
545 | unsigned long *next; | |
546 | unsigned int *next_set; | |
547 | }; | |
548 | ||
549 | static void blk_mq_timeout_check(void *__data, unsigned long *free_tags) | |
550 | { | |
551 | struct blk_mq_timeout_data *data = __data; | |
552 | struct blk_mq_hw_ctx *hctx = data->hctx; | |
553 | unsigned int tag; | |
554 | ||
555 | /* It may not be in flight yet (this is where | |
556 | * the REQ_ATOMIC_STARTED flag comes in). The requests are | |
557 | * statically allocated, so we know it's always safe to access the | |
558 | * memory associated with a bit offset into ->rqs[]. | |
559 | */ | |
560 | tag = 0; | |
561 | do { | |
562 | struct request *rq; | |
563 | ||
24d2f903 CH |
564 | tag = find_next_zero_bit(free_tags, hctx->tags->nr_tags, tag); |
565 | if (tag >= hctx->tags->nr_tags) | |
320ae51f JA |
566 | break; |
567 | ||
0e62f51f | 568 | rq = blk_mq_tag_to_rq(hctx->tags, tag++); |
24d2f903 CH |
569 | if (rq->q != hctx->queue) |
570 | continue; | |
320ae51f JA |
571 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
572 | continue; | |
573 | ||
574 | blk_rq_check_expired(rq, data->next, data->next_set); | |
575 | } while (1); | |
576 | } | |
577 | ||
578 | static void blk_mq_hw_ctx_check_timeout(struct blk_mq_hw_ctx *hctx, | |
579 | unsigned long *next, | |
580 | unsigned int *next_set) | |
581 | { | |
582 | struct blk_mq_timeout_data data = { | |
583 | .hctx = hctx, | |
584 | .next = next, | |
585 | .next_set = next_set, | |
586 | }; | |
587 | ||
588 | /* | |
589 | * Ask the tagging code to iterate busy requests, so we can | |
590 | * check them for timeout. | |
591 | */ | |
592 | blk_mq_tag_busy_iter(hctx->tags, blk_mq_timeout_check, &data); | |
593 | } | |
594 | ||
87ee7b11 JA |
595 | static enum blk_eh_timer_return blk_mq_rq_timed_out(struct request *rq) |
596 | { | |
597 | struct request_queue *q = rq->q; | |
598 | ||
599 | /* | |
600 | * We know that complete is set at this point. If STARTED isn't set | |
601 | * anymore, then the request isn't active and the "timeout" should | |
602 | * just be ignored. This can happen due to the bitflag ordering. | |
603 | * Timeout first checks if STARTED is set, and if it is, assumes | |
604 | * the request is active. But if we race with completion, then | |
605 | * we both flags will get cleared. So check here again, and ignore | |
606 | * a timeout event with a request that isn't active. | |
607 | */ | |
608 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) | |
609 | return BLK_EH_NOT_HANDLED; | |
610 | ||
611 | if (!q->mq_ops->timeout) | |
612 | return BLK_EH_RESET_TIMER; | |
613 | ||
614 | return q->mq_ops->timeout(rq); | |
615 | } | |
616 | ||
320ae51f JA |
617 | static void blk_mq_rq_timer(unsigned long data) |
618 | { | |
619 | struct request_queue *q = (struct request_queue *) data; | |
620 | struct blk_mq_hw_ctx *hctx; | |
621 | unsigned long next = 0; | |
622 | int i, next_set = 0; | |
623 | ||
484b4061 JA |
624 | queue_for_each_hw_ctx(q, hctx, i) { |
625 | /* | |
626 | * If not software queues are currently mapped to this | |
627 | * hardware queue, there's nothing to check | |
628 | */ | |
629 | if (!hctx->nr_ctx || !hctx->tags) | |
630 | continue; | |
631 | ||
320ae51f | 632 | blk_mq_hw_ctx_check_timeout(hctx, &next, &next_set); |
484b4061 | 633 | } |
320ae51f | 634 | |
0d2602ca JA |
635 | if (next_set) { |
636 | next = blk_rq_timeout(round_jiffies_up(next)); | |
637 | mod_timer(&q->timeout, next); | |
638 | } else { | |
639 | queue_for_each_hw_ctx(q, hctx, i) | |
640 | blk_mq_tag_idle(hctx); | |
641 | } | |
320ae51f JA |
642 | } |
643 | ||
644 | /* | |
645 | * Reverse check our software queue for entries that we could potentially | |
646 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
647 | * too much time checking for merges. | |
648 | */ | |
649 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
650 | struct blk_mq_ctx *ctx, struct bio *bio) | |
651 | { | |
652 | struct request *rq; | |
653 | int checked = 8; | |
654 | ||
655 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
656 | int el_ret; | |
657 | ||
658 | if (!checked--) | |
659 | break; | |
660 | ||
661 | if (!blk_rq_merge_ok(rq, bio)) | |
662 | continue; | |
663 | ||
664 | el_ret = blk_try_merge(rq, bio); | |
665 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
666 | if (bio_attempt_back_merge(q, rq, bio)) { | |
667 | ctx->rq_merged++; | |
668 | return true; | |
669 | } | |
670 | break; | |
671 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
672 | if (bio_attempt_front_merge(q, rq, bio)) { | |
673 | ctx->rq_merged++; | |
674 | return true; | |
675 | } | |
676 | break; | |
677 | } | |
678 | } | |
679 | ||
680 | return false; | |
681 | } | |
682 | ||
1429d7c9 JA |
683 | /* |
684 | * Process software queues that have been marked busy, splicing them | |
685 | * to the for-dispatch | |
686 | */ | |
687 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
688 | { | |
689 | struct blk_mq_ctx *ctx; | |
690 | int i; | |
691 | ||
692 | for (i = 0; i < hctx->ctx_map.map_size; i++) { | |
693 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; | |
694 | unsigned int off, bit; | |
695 | ||
696 | if (!bm->word) | |
697 | continue; | |
698 | ||
699 | bit = 0; | |
700 | off = i * hctx->ctx_map.bits_per_word; | |
701 | do { | |
702 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
703 | if (bit >= bm->depth) | |
704 | break; | |
705 | ||
706 | ctx = hctx->ctxs[bit + off]; | |
707 | clear_bit(bit, &bm->word); | |
708 | spin_lock(&ctx->lock); | |
709 | list_splice_tail_init(&ctx->rq_list, list); | |
710 | spin_unlock(&ctx->lock); | |
711 | ||
712 | bit++; | |
713 | } while (1); | |
714 | } | |
715 | } | |
716 | ||
320ae51f JA |
717 | /* |
718 | * Run this hardware queue, pulling any software queues mapped to it in. | |
719 | * Note that this function currently has various problems around ordering | |
720 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
721 | * items on the hctx->dispatch list. Ignore that for now. | |
722 | */ | |
723 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
724 | { | |
725 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
726 | struct request *rq; |
727 | LIST_HEAD(rq_list); | |
1429d7c9 | 728 | int queued; |
320ae51f | 729 | |
fd1270d5 | 730 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 731 | |
5d12f905 | 732 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
733 | return; |
734 | ||
735 | hctx->run++; | |
736 | ||
737 | /* | |
738 | * Touch any software queue that has pending entries. | |
739 | */ | |
1429d7c9 | 740 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
741 | |
742 | /* | |
743 | * If we have previous entries on our dispatch list, grab them | |
744 | * and stuff them at the front for more fair dispatch. | |
745 | */ | |
746 | if (!list_empty_careful(&hctx->dispatch)) { | |
747 | spin_lock(&hctx->lock); | |
748 | if (!list_empty(&hctx->dispatch)) | |
749 | list_splice_init(&hctx->dispatch, &rq_list); | |
750 | spin_unlock(&hctx->lock); | |
751 | } | |
752 | ||
320ae51f JA |
753 | /* |
754 | * Now process all the entries, sending them to the driver. | |
755 | */ | |
1429d7c9 | 756 | queued = 0; |
320ae51f JA |
757 | while (!list_empty(&rq_list)) { |
758 | int ret; | |
759 | ||
760 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
761 | list_del_init(&rq->queuelist); | |
320ae51f | 762 | |
49f5baa5 | 763 | blk_mq_start_request(rq, list_empty(&rq_list)); |
320ae51f JA |
764 | |
765 | ret = q->mq_ops->queue_rq(hctx, rq); | |
766 | switch (ret) { | |
767 | case BLK_MQ_RQ_QUEUE_OK: | |
768 | queued++; | |
769 | continue; | |
770 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 771 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 772 | __blk_mq_requeue_request(rq); |
320ae51f JA |
773 | break; |
774 | default: | |
775 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 776 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 777 | rq->errors = -EIO; |
320ae51f JA |
778 | blk_mq_end_io(rq, rq->errors); |
779 | break; | |
780 | } | |
781 | ||
782 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
783 | break; | |
784 | } | |
785 | ||
786 | if (!queued) | |
787 | hctx->dispatched[0]++; | |
788 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
789 | hctx->dispatched[ilog2(queued) + 1]++; | |
790 | ||
791 | /* | |
792 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
793 | * that is where we will continue on next queue run. | |
794 | */ | |
795 | if (!list_empty(&rq_list)) { | |
796 | spin_lock(&hctx->lock); | |
797 | list_splice(&rq_list, &hctx->dispatch); | |
798 | spin_unlock(&hctx->lock); | |
799 | } | |
800 | } | |
801 | ||
506e931f JA |
802 | /* |
803 | * It'd be great if the workqueue API had a way to pass | |
804 | * in a mask and had some smarts for more clever placement. | |
805 | * For now we just round-robin here, switching for every | |
806 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
807 | */ | |
808 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
809 | { | |
810 | int cpu = hctx->next_cpu; | |
811 | ||
812 | if (--hctx->next_cpu_batch <= 0) { | |
813 | int next_cpu; | |
814 | ||
815 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
816 | if (next_cpu >= nr_cpu_ids) | |
817 | next_cpu = cpumask_first(hctx->cpumask); | |
818 | ||
819 | hctx->next_cpu = next_cpu; | |
820 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
821 | } | |
822 | ||
823 | return cpu; | |
824 | } | |
825 | ||
320ae51f JA |
826 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
827 | { | |
5d12f905 | 828 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
829 | return; |
830 | ||
e4043dcf | 831 | if (!async && cpumask_test_cpu(smp_processor_id(), hctx->cpumask)) |
320ae51f | 832 | __blk_mq_run_hw_queue(hctx); |
e4043dcf | 833 | else if (hctx->queue->nr_hw_queues == 1) |
70f4db63 | 834 | kblockd_schedule_delayed_work(&hctx->run_work, 0); |
e4043dcf JA |
835 | else { |
836 | unsigned int cpu; | |
837 | ||
506e931f | 838 | cpu = blk_mq_hctx_next_cpu(hctx); |
70f4db63 | 839 | kblockd_schedule_delayed_work_on(cpu, &hctx->run_work, 0); |
e4043dcf | 840 | } |
320ae51f JA |
841 | } |
842 | ||
843 | void blk_mq_run_queues(struct request_queue *q, bool async) | |
844 | { | |
845 | struct blk_mq_hw_ctx *hctx; | |
846 | int i; | |
847 | ||
848 | queue_for_each_hw_ctx(q, hctx, i) { | |
849 | if ((!blk_mq_hctx_has_pending(hctx) && | |
850 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 851 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
852 | continue; |
853 | ||
e4043dcf | 854 | preempt_disable(); |
320ae51f | 855 | blk_mq_run_hw_queue(hctx, async); |
e4043dcf | 856 | preempt_enable(); |
320ae51f JA |
857 | } |
858 | } | |
859 | EXPORT_SYMBOL(blk_mq_run_queues); | |
860 | ||
861 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
862 | { | |
70f4db63 CH |
863 | cancel_delayed_work(&hctx->run_work); |
864 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
865 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
866 | } | |
867 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
868 | ||
280d45f6 CH |
869 | void blk_mq_stop_hw_queues(struct request_queue *q) |
870 | { | |
871 | struct blk_mq_hw_ctx *hctx; | |
872 | int i; | |
873 | ||
874 | queue_for_each_hw_ctx(q, hctx, i) | |
875 | blk_mq_stop_hw_queue(hctx); | |
876 | } | |
877 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
878 | ||
320ae51f JA |
879 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
880 | { | |
881 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf JA |
882 | |
883 | preempt_disable(); | |
0ffbce80 | 884 | blk_mq_run_hw_queue(hctx, false); |
e4043dcf | 885 | preempt_enable(); |
320ae51f JA |
886 | } |
887 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
888 | ||
2f268556 CH |
889 | void blk_mq_start_hw_queues(struct request_queue *q) |
890 | { | |
891 | struct blk_mq_hw_ctx *hctx; | |
892 | int i; | |
893 | ||
894 | queue_for_each_hw_ctx(q, hctx, i) | |
895 | blk_mq_start_hw_queue(hctx); | |
896 | } | |
897 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
898 | ||
899 | ||
1b4a3258 | 900 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
901 | { |
902 | struct blk_mq_hw_ctx *hctx; | |
903 | int i; | |
904 | ||
905 | queue_for_each_hw_ctx(q, hctx, i) { | |
906 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
907 | continue; | |
908 | ||
909 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 910 | preempt_disable(); |
1b4a3258 | 911 | blk_mq_run_hw_queue(hctx, async); |
e4043dcf | 912 | preempt_enable(); |
320ae51f JA |
913 | } |
914 | } | |
915 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
916 | ||
70f4db63 | 917 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
918 | { |
919 | struct blk_mq_hw_ctx *hctx; | |
920 | ||
70f4db63 | 921 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 922 | |
320ae51f JA |
923 | __blk_mq_run_hw_queue(hctx); |
924 | } | |
925 | ||
70f4db63 CH |
926 | static void blk_mq_delay_work_fn(struct work_struct *work) |
927 | { | |
928 | struct blk_mq_hw_ctx *hctx; | |
929 | ||
930 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
931 | ||
932 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
933 | __blk_mq_run_hw_queue(hctx); | |
934 | } | |
935 | ||
936 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
937 | { | |
938 | unsigned long tmo = msecs_to_jiffies(msecs); | |
939 | ||
940 | if (hctx->queue->nr_hw_queues == 1) | |
941 | kblockd_schedule_delayed_work(&hctx->delay_work, tmo); | |
942 | else { | |
943 | unsigned int cpu; | |
944 | ||
506e931f | 945 | cpu = blk_mq_hctx_next_cpu(hctx); |
70f4db63 CH |
946 | kblockd_schedule_delayed_work_on(cpu, &hctx->delay_work, tmo); |
947 | } | |
948 | } | |
949 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
950 | ||
320ae51f | 951 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
72a0a36e | 952 | struct request *rq, bool at_head) |
320ae51f JA |
953 | { |
954 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
955 | ||
01b983c9 JA |
956 | trace_block_rq_insert(hctx->queue, rq); |
957 | ||
72a0a36e CH |
958 | if (at_head) |
959 | list_add(&rq->queuelist, &ctx->rq_list); | |
960 | else | |
961 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
4bb659b1 | 962 | |
320ae51f | 963 | blk_mq_hctx_mark_pending(hctx, ctx); |
320ae51f JA |
964 | } |
965 | ||
eeabc850 CH |
966 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
967 | bool async) | |
320ae51f | 968 | { |
eeabc850 | 969 | struct request_queue *q = rq->q; |
320ae51f | 970 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
971 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
972 | ||
973 | current_ctx = blk_mq_get_ctx(q); | |
974 | if (!cpu_online(ctx->cpu)) | |
975 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 976 | |
320ae51f JA |
977 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
978 | ||
a57a178a CH |
979 | spin_lock(&ctx->lock); |
980 | __blk_mq_insert_request(hctx, rq, at_head); | |
981 | spin_unlock(&ctx->lock); | |
320ae51f | 982 | |
320ae51f JA |
983 | if (run_queue) |
984 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
985 | |
986 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
987 | } |
988 | ||
989 | static void blk_mq_insert_requests(struct request_queue *q, | |
990 | struct blk_mq_ctx *ctx, | |
991 | struct list_head *list, | |
992 | int depth, | |
993 | bool from_schedule) | |
994 | ||
995 | { | |
996 | struct blk_mq_hw_ctx *hctx; | |
997 | struct blk_mq_ctx *current_ctx; | |
998 | ||
999 | trace_block_unplug(q, depth, !from_schedule); | |
1000 | ||
1001 | current_ctx = blk_mq_get_ctx(q); | |
1002 | ||
1003 | if (!cpu_online(ctx->cpu)) | |
1004 | ctx = current_ctx; | |
1005 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1006 | ||
1007 | /* | |
1008 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
1009 | * offline now | |
1010 | */ | |
1011 | spin_lock(&ctx->lock); | |
1012 | while (!list_empty(list)) { | |
1013 | struct request *rq; | |
1014 | ||
1015 | rq = list_first_entry(list, struct request, queuelist); | |
1016 | list_del_init(&rq->queuelist); | |
1017 | rq->mq_ctx = ctx; | |
72a0a36e | 1018 | __blk_mq_insert_request(hctx, rq, false); |
320ae51f JA |
1019 | } |
1020 | spin_unlock(&ctx->lock); | |
1021 | ||
320ae51f | 1022 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 1023 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
1024 | } |
1025 | ||
1026 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1027 | { | |
1028 | struct request *rqa = container_of(a, struct request, queuelist); | |
1029 | struct request *rqb = container_of(b, struct request, queuelist); | |
1030 | ||
1031 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1032 | (rqa->mq_ctx == rqb->mq_ctx && | |
1033 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1034 | } | |
1035 | ||
1036 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1037 | { | |
1038 | struct blk_mq_ctx *this_ctx; | |
1039 | struct request_queue *this_q; | |
1040 | struct request *rq; | |
1041 | LIST_HEAD(list); | |
1042 | LIST_HEAD(ctx_list); | |
1043 | unsigned int depth; | |
1044 | ||
1045 | list_splice_init(&plug->mq_list, &list); | |
1046 | ||
1047 | list_sort(NULL, &list, plug_ctx_cmp); | |
1048 | ||
1049 | this_q = NULL; | |
1050 | this_ctx = NULL; | |
1051 | depth = 0; | |
1052 | ||
1053 | while (!list_empty(&list)) { | |
1054 | rq = list_entry_rq(list.next); | |
1055 | list_del_init(&rq->queuelist); | |
1056 | BUG_ON(!rq->q); | |
1057 | if (rq->mq_ctx != this_ctx) { | |
1058 | if (this_ctx) { | |
1059 | blk_mq_insert_requests(this_q, this_ctx, | |
1060 | &ctx_list, depth, | |
1061 | from_schedule); | |
1062 | } | |
1063 | ||
1064 | this_ctx = rq->mq_ctx; | |
1065 | this_q = rq->q; | |
1066 | depth = 0; | |
1067 | } | |
1068 | ||
1069 | depth++; | |
1070 | list_add_tail(&rq->queuelist, &ctx_list); | |
1071 | } | |
1072 | ||
1073 | /* | |
1074 | * If 'this_ctx' is set, we know we have entries to complete | |
1075 | * on 'ctx_list'. Do those. | |
1076 | */ | |
1077 | if (this_ctx) { | |
1078 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1079 | from_schedule); | |
1080 | } | |
1081 | } | |
1082 | ||
1083 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1084 | { | |
1085 | init_request_from_bio(rq, bio); | |
4b570521 | 1086 | |
3ee32372 | 1087 | if (blk_do_io_stat(rq)) |
4b570521 | 1088 | blk_account_io_start(rq, 1); |
320ae51f JA |
1089 | } |
1090 | ||
274a5843 JA |
1091 | static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx) |
1092 | { | |
1093 | return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) && | |
1094 | !blk_queue_nomerges(hctx->queue); | |
1095 | } | |
1096 | ||
07068d5b JA |
1097 | static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, |
1098 | struct blk_mq_ctx *ctx, | |
1099 | struct request *rq, struct bio *bio) | |
320ae51f | 1100 | { |
274a5843 | 1101 | if (!hctx_allow_merges(hctx)) { |
07068d5b JA |
1102 | blk_mq_bio_to_request(rq, bio); |
1103 | spin_lock(&ctx->lock); | |
1104 | insert_rq: | |
1105 | __blk_mq_insert_request(hctx, rq, false); | |
1106 | spin_unlock(&ctx->lock); | |
1107 | return false; | |
1108 | } else { | |
274a5843 JA |
1109 | struct request_queue *q = hctx->queue; |
1110 | ||
07068d5b JA |
1111 | spin_lock(&ctx->lock); |
1112 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
1113 | blk_mq_bio_to_request(rq, bio); | |
1114 | goto insert_rq; | |
1115 | } | |
320ae51f | 1116 | |
07068d5b JA |
1117 | spin_unlock(&ctx->lock); |
1118 | __blk_mq_free_request(hctx, ctx, rq); | |
1119 | return true; | |
14ec77f3 | 1120 | } |
07068d5b | 1121 | } |
14ec77f3 | 1122 | |
07068d5b JA |
1123 | struct blk_map_ctx { |
1124 | struct blk_mq_hw_ctx *hctx; | |
1125 | struct blk_mq_ctx *ctx; | |
1126 | }; | |
1127 | ||
1128 | static struct request *blk_mq_map_request(struct request_queue *q, | |
1129 | struct bio *bio, | |
1130 | struct blk_map_ctx *data) | |
1131 | { | |
1132 | struct blk_mq_hw_ctx *hctx; | |
1133 | struct blk_mq_ctx *ctx; | |
1134 | struct request *rq; | |
1135 | int rw = bio_data_dir(bio); | |
cb96a42c | 1136 | struct blk_mq_alloc_data alloc_data; |
320ae51f | 1137 | |
07068d5b | 1138 | if (unlikely(blk_mq_queue_enter(q))) { |
320ae51f | 1139 | bio_endio(bio, -EIO); |
07068d5b | 1140 | return NULL; |
320ae51f JA |
1141 | } |
1142 | ||
1143 | ctx = blk_mq_get_ctx(q); | |
1144 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1145 | ||
07068d5b | 1146 | if (rw_is_sync(bio->bi_rw)) |
27fbf4e8 | 1147 | rw |= REQ_SYNC; |
07068d5b | 1148 | |
320ae51f | 1149 | trace_block_getrq(q, bio, rw); |
cb96a42c ML |
1150 | blk_mq_set_alloc_data(&alloc_data, q, GFP_ATOMIC, false, ctx, |
1151 | hctx); | |
1152 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
5dee8577 | 1153 | if (unlikely(!rq)) { |
793597a6 | 1154 | __blk_mq_run_hw_queue(hctx); |
320ae51f JA |
1155 | blk_mq_put_ctx(ctx); |
1156 | trace_block_sleeprq(q, bio, rw); | |
793597a6 CH |
1157 | |
1158 | ctx = blk_mq_get_ctx(q); | |
320ae51f | 1159 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
cb96a42c ML |
1160 | blk_mq_set_alloc_data(&alloc_data, q, |
1161 | __GFP_WAIT|GFP_ATOMIC, false, ctx, hctx); | |
1162 | rq = __blk_mq_alloc_request(&alloc_data, rw); | |
1163 | ctx = alloc_data.ctx; | |
1164 | hctx = alloc_data.hctx; | |
320ae51f JA |
1165 | } |
1166 | ||
1167 | hctx->queued++; | |
07068d5b JA |
1168 | data->hctx = hctx; |
1169 | data->ctx = ctx; | |
1170 | return rq; | |
1171 | } | |
1172 | ||
1173 | /* | |
1174 | * Multiple hardware queue variant. This will not use per-process plugs, | |
1175 | * but will attempt to bypass the hctx queueing if we can go straight to | |
1176 | * hardware for SYNC IO. | |
1177 | */ | |
1178 | static void blk_mq_make_request(struct request_queue *q, struct bio *bio) | |
1179 | { | |
1180 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1181 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1182 | struct blk_map_ctx data; | |
1183 | struct request *rq; | |
1184 | ||
1185 | blk_queue_bounce(q, &bio); | |
1186 | ||
1187 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1188 | bio_endio(bio, -EIO); | |
1189 | return; | |
1190 | } | |
1191 | ||
1192 | rq = blk_mq_map_request(q, bio, &data); | |
1193 | if (unlikely(!rq)) | |
1194 | return; | |
1195 | ||
1196 | if (unlikely(is_flush_fua)) { | |
1197 | blk_mq_bio_to_request(rq, bio); | |
1198 | blk_insert_flush(rq); | |
1199 | goto run_queue; | |
1200 | } | |
1201 | ||
1202 | if (is_sync) { | |
1203 | int ret; | |
1204 | ||
1205 | blk_mq_bio_to_request(rq, bio); | |
1206 | blk_mq_start_request(rq, true); | |
1207 | ||
1208 | /* | |
1209 | * For OK queue, we are done. For error, kill it. Any other | |
1210 | * error (busy), just add it to our list as we previously | |
1211 | * would have done | |
1212 | */ | |
1213 | ret = q->mq_ops->queue_rq(data.hctx, rq); | |
1214 | if (ret == BLK_MQ_RQ_QUEUE_OK) | |
1215 | goto done; | |
1216 | else { | |
1217 | __blk_mq_requeue_request(rq); | |
1218 | ||
1219 | if (ret == BLK_MQ_RQ_QUEUE_ERROR) { | |
1220 | rq->errors = -EIO; | |
1221 | blk_mq_end_io(rq, rq->errors); | |
1222 | goto done; | |
1223 | } | |
1224 | } | |
1225 | } | |
1226 | ||
1227 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { | |
1228 | /* | |
1229 | * For a SYNC request, send it to the hardware immediately. For | |
1230 | * an ASYNC request, just ensure that we run it later on. The | |
1231 | * latter allows for merging opportunities and more efficient | |
1232 | * dispatching. | |
1233 | */ | |
1234 | run_queue: | |
1235 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
1236 | } | |
1237 | done: | |
1238 | blk_mq_put_ctx(data.ctx); | |
1239 | } | |
1240 | ||
1241 | /* | |
1242 | * Single hardware queue variant. This will attempt to use any per-process | |
1243 | * plug for merging and IO deferral. | |
1244 | */ | |
1245 | static void blk_sq_make_request(struct request_queue *q, struct bio *bio) | |
1246 | { | |
1247 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1248 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1249 | unsigned int use_plug, request_count = 0; | |
1250 | struct blk_map_ctx data; | |
1251 | struct request *rq; | |
1252 | ||
1253 | /* | |
1254 | * If we have multiple hardware queues, just go directly to | |
1255 | * one of those for sync IO. | |
1256 | */ | |
1257 | use_plug = !is_flush_fua && !is_sync; | |
1258 | ||
1259 | blk_queue_bounce(q, &bio); | |
1260 | ||
1261 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { | |
1262 | bio_endio(bio, -EIO); | |
1263 | return; | |
1264 | } | |
1265 | ||
1266 | if (use_plug && !blk_queue_nomerges(q) && | |
1267 | blk_attempt_plug_merge(q, bio, &request_count)) | |
1268 | return; | |
1269 | ||
1270 | rq = blk_mq_map_request(q, bio, &data); | |
ff87bcec JA |
1271 | if (unlikely(!rq)) |
1272 | return; | |
320ae51f JA |
1273 | |
1274 | if (unlikely(is_flush_fua)) { | |
1275 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1276 | blk_insert_flush(rq); |
1277 | goto run_queue; | |
1278 | } | |
1279 | ||
1280 | /* | |
1281 | * A task plug currently exists. Since this is completely lockless, | |
1282 | * utilize that to temporarily store requests until the task is | |
1283 | * either done or scheduled away. | |
1284 | */ | |
1285 | if (use_plug) { | |
1286 | struct blk_plug *plug = current->plug; | |
1287 | ||
1288 | if (plug) { | |
1289 | blk_mq_bio_to_request(rq, bio); | |
92f399c7 | 1290 | if (list_empty(&plug->mq_list)) |
320ae51f JA |
1291 | trace_block_plug(q); |
1292 | else if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
1293 | blk_flush_plug_list(plug, false); | |
1294 | trace_block_plug(q); | |
1295 | } | |
1296 | list_add_tail(&rq->queuelist, &plug->mq_list); | |
07068d5b | 1297 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1298 | return; |
1299 | } | |
1300 | } | |
1301 | ||
07068d5b JA |
1302 | if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { |
1303 | /* | |
1304 | * For a SYNC request, send it to the hardware immediately. For | |
1305 | * an ASYNC request, just ensure that we run it later on. The | |
1306 | * latter allows for merging opportunities and more efficient | |
1307 | * dispatching. | |
1308 | */ | |
1309 | run_queue: | |
1310 | blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); | |
320ae51f JA |
1311 | } |
1312 | ||
07068d5b | 1313 | blk_mq_put_ctx(data.ctx); |
320ae51f JA |
1314 | } |
1315 | ||
1316 | /* | |
1317 | * Default mapping to a software queue, since we use one per CPU. | |
1318 | */ | |
1319 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1320 | { | |
1321 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1322 | } | |
1323 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1324 | ||
24d2f903 CH |
1325 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1326 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1327 | { |
e9b267d9 | 1328 | struct page *page; |
320ae51f | 1329 | |
24d2f903 | 1330 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1331 | int i; |
320ae51f | 1332 | |
24d2f903 CH |
1333 | for (i = 0; i < tags->nr_tags; i++) { |
1334 | if (!tags->rqs[i]) | |
e9b267d9 | 1335 | continue; |
24d2f903 CH |
1336 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1337 | hctx_idx, i); | |
a5164405 | 1338 | tags->rqs[i] = NULL; |
e9b267d9 | 1339 | } |
320ae51f | 1340 | } |
320ae51f | 1341 | |
24d2f903 CH |
1342 | while (!list_empty(&tags->page_list)) { |
1343 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1344 | list_del_init(&page->lru); |
320ae51f JA |
1345 | __free_pages(page, page->private); |
1346 | } | |
1347 | ||
24d2f903 | 1348 | kfree(tags->rqs); |
320ae51f | 1349 | |
24d2f903 | 1350 | blk_mq_free_tags(tags); |
320ae51f JA |
1351 | } |
1352 | ||
1353 | static size_t order_to_size(unsigned int order) | |
1354 | { | |
4ca08500 | 1355 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1356 | } |
1357 | ||
24d2f903 CH |
1358 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1359 | unsigned int hctx_idx) | |
320ae51f | 1360 | { |
24d2f903 | 1361 | struct blk_mq_tags *tags; |
320ae51f JA |
1362 | unsigned int i, j, entries_per_page, max_order = 4; |
1363 | size_t rq_size, left; | |
1364 | ||
24d2f903 CH |
1365 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
1366 | set->numa_node); | |
1367 | if (!tags) | |
1368 | return NULL; | |
320ae51f | 1369 | |
24d2f903 CH |
1370 | INIT_LIST_HEAD(&tags->page_list); |
1371 | ||
a5164405 JA |
1372 | tags->rqs = kzalloc_node(set->queue_depth * sizeof(struct request *), |
1373 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1374 | set->numa_node); | |
24d2f903 CH |
1375 | if (!tags->rqs) { |
1376 | blk_mq_free_tags(tags); | |
1377 | return NULL; | |
1378 | } | |
320ae51f JA |
1379 | |
1380 | /* | |
1381 | * rq_size is the size of the request plus driver payload, rounded | |
1382 | * to the cacheline size | |
1383 | */ | |
24d2f903 | 1384 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1385 | cache_line_size()); |
24d2f903 | 1386 | left = rq_size * set->queue_depth; |
320ae51f | 1387 | |
24d2f903 | 1388 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1389 | int this_order = max_order; |
1390 | struct page *page; | |
1391 | int to_do; | |
1392 | void *p; | |
1393 | ||
1394 | while (left < order_to_size(this_order - 1) && this_order) | |
1395 | this_order--; | |
1396 | ||
1397 | do { | |
a5164405 JA |
1398 | page = alloc_pages_node(set->numa_node, |
1399 | GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, | |
1400 | this_order); | |
320ae51f JA |
1401 | if (page) |
1402 | break; | |
1403 | if (!this_order--) | |
1404 | break; | |
1405 | if (order_to_size(this_order) < rq_size) | |
1406 | break; | |
1407 | } while (1); | |
1408 | ||
1409 | if (!page) | |
24d2f903 | 1410 | goto fail; |
320ae51f JA |
1411 | |
1412 | page->private = this_order; | |
24d2f903 | 1413 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1414 | |
1415 | p = page_address(page); | |
1416 | entries_per_page = order_to_size(this_order) / rq_size; | |
24d2f903 | 1417 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1418 | left -= to_do * rq_size; |
1419 | for (j = 0; j < to_do; j++) { | |
24d2f903 | 1420 | tags->rqs[i] = p; |
683d0e12 DH |
1421 | tags->rqs[i]->atomic_flags = 0; |
1422 | tags->rqs[i]->cmd_flags = 0; | |
24d2f903 CH |
1423 | if (set->ops->init_request) { |
1424 | if (set->ops->init_request(set->driver_data, | |
1425 | tags->rqs[i], hctx_idx, i, | |
a5164405 JA |
1426 | set->numa_node)) { |
1427 | tags->rqs[i] = NULL; | |
24d2f903 | 1428 | goto fail; |
a5164405 | 1429 | } |
e9b267d9 CH |
1430 | } |
1431 | ||
320ae51f JA |
1432 | p += rq_size; |
1433 | i++; | |
1434 | } | |
1435 | } | |
1436 | ||
24d2f903 | 1437 | return tags; |
320ae51f | 1438 | |
24d2f903 | 1439 | fail: |
24d2f903 CH |
1440 | blk_mq_free_rq_map(set, tags, hctx_idx); |
1441 | return NULL; | |
320ae51f JA |
1442 | } |
1443 | ||
1429d7c9 JA |
1444 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1445 | { | |
1446 | kfree(bitmap->map); | |
1447 | } | |
1448 | ||
1449 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1450 | { | |
1451 | unsigned int bpw = 8, total, num_maps, i; | |
1452 | ||
1453 | bitmap->bits_per_word = bpw; | |
1454 | ||
1455 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1456 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1457 | GFP_KERNEL, node); | |
1458 | if (!bitmap->map) | |
1459 | return -ENOMEM; | |
1460 | ||
1461 | bitmap->map_size = num_maps; | |
1462 | ||
1463 | total = nr_cpu_ids; | |
1464 | for (i = 0; i < num_maps; i++) { | |
1465 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1466 | total -= bitmap->map[i].depth; | |
1467 | } | |
1468 | ||
1469 | return 0; | |
1470 | } | |
1471 | ||
484b4061 JA |
1472 | static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) |
1473 | { | |
1474 | struct request_queue *q = hctx->queue; | |
1475 | struct blk_mq_ctx *ctx; | |
1476 | LIST_HEAD(tmp); | |
1477 | ||
1478 | /* | |
1479 | * Move ctx entries to new CPU, if this one is going away. | |
1480 | */ | |
1481 | ctx = __blk_mq_get_ctx(q, cpu); | |
1482 | ||
1483 | spin_lock(&ctx->lock); | |
1484 | if (!list_empty(&ctx->rq_list)) { | |
1485 | list_splice_init(&ctx->rq_list, &tmp); | |
1486 | blk_mq_hctx_clear_pending(hctx, ctx); | |
1487 | } | |
1488 | spin_unlock(&ctx->lock); | |
1489 | ||
1490 | if (list_empty(&tmp)) | |
1491 | return NOTIFY_OK; | |
1492 | ||
1493 | ctx = blk_mq_get_ctx(q); | |
1494 | spin_lock(&ctx->lock); | |
1495 | ||
1496 | while (!list_empty(&tmp)) { | |
1497 | struct request *rq; | |
1498 | ||
1499 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1500 | rq->mq_ctx = ctx; | |
1501 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1502 | } | |
1503 | ||
1504 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1505 | blk_mq_hctx_mark_pending(hctx, ctx); | |
1506 | ||
1507 | spin_unlock(&ctx->lock); | |
1508 | ||
1509 | blk_mq_run_hw_queue(hctx, true); | |
1510 | blk_mq_put_ctx(ctx); | |
1511 | return NOTIFY_OK; | |
1512 | } | |
1513 | ||
1514 | static int blk_mq_hctx_cpu_online(struct blk_mq_hw_ctx *hctx, int cpu) | |
1515 | { | |
1516 | struct request_queue *q = hctx->queue; | |
1517 | struct blk_mq_tag_set *set = q->tag_set; | |
1518 | ||
1519 | if (set->tags[hctx->queue_num]) | |
1520 | return NOTIFY_OK; | |
1521 | ||
1522 | set->tags[hctx->queue_num] = blk_mq_init_rq_map(set, hctx->queue_num); | |
1523 | if (!set->tags[hctx->queue_num]) | |
1524 | return NOTIFY_STOP; | |
1525 | ||
1526 | hctx->tags = set->tags[hctx->queue_num]; | |
1527 | return NOTIFY_OK; | |
1528 | } | |
1529 | ||
1530 | static int blk_mq_hctx_notify(void *data, unsigned long action, | |
1531 | unsigned int cpu) | |
1532 | { | |
1533 | struct blk_mq_hw_ctx *hctx = data; | |
1534 | ||
1535 | if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) | |
1536 | return blk_mq_hctx_cpu_offline(hctx, cpu); | |
1537 | else if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) | |
1538 | return blk_mq_hctx_cpu_online(hctx, cpu); | |
1539 | ||
1540 | return NOTIFY_OK; | |
1541 | } | |
1542 | ||
624dbe47 ML |
1543 | static void blk_mq_exit_hw_queues(struct request_queue *q, |
1544 | struct blk_mq_tag_set *set, int nr_queue) | |
1545 | { | |
1546 | struct blk_mq_hw_ctx *hctx; | |
1547 | unsigned int i; | |
1548 | ||
1549 | queue_for_each_hw_ctx(q, hctx, i) { | |
1550 | if (i == nr_queue) | |
1551 | break; | |
1552 | ||
f899fed4 JA |
1553 | blk_mq_tag_idle(hctx); |
1554 | ||
624dbe47 ML |
1555 | if (set->ops->exit_hctx) |
1556 | set->ops->exit_hctx(hctx, i); | |
1557 | ||
1558 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
1559 | kfree(hctx->ctxs); | |
1560 | blk_mq_free_bitmap(&hctx->ctx_map); | |
1561 | } | |
1562 | ||
1563 | } | |
1564 | ||
1565 | static void blk_mq_free_hw_queues(struct request_queue *q, | |
1566 | struct blk_mq_tag_set *set) | |
1567 | { | |
1568 | struct blk_mq_hw_ctx *hctx; | |
1569 | unsigned int i; | |
1570 | ||
1571 | queue_for_each_hw_ctx(q, hctx, i) { | |
1572 | free_cpumask_var(hctx->cpumask); | |
cdef54dd | 1573 | kfree(hctx); |
624dbe47 ML |
1574 | } |
1575 | } | |
1576 | ||
320ae51f | 1577 | static int blk_mq_init_hw_queues(struct request_queue *q, |
24d2f903 | 1578 | struct blk_mq_tag_set *set) |
320ae51f JA |
1579 | { |
1580 | struct blk_mq_hw_ctx *hctx; | |
624dbe47 | 1581 | unsigned int i; |
320ae51f JA |
1582 | |
1583 | /* | |
1584 | * Initialize hardware queues | |
1585 | */ | |
1586 | queue_for_each_hw_ctx(q, hctx, i) { | |
320ae51f JA |
1587 | int node; |
1588 | ||
1589 | node = hctx->numa_node; | |
1590 | if (node == NUMA_NO_NODE) | |
24d2f903 | 1591 | node = hctx->numa_node = set->numa_node; |
320ae51f | 1592 | |
70f4db63 CH |
1593 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); |
1594 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
320ae51f JA |
1595 | spin_lock_init(&hctx->lock); |
1596 | INIT_LIST_HEAD(&hctx->dispatch); | |
1597 | hctx->queue = q; | |
1598 | hctx->queue_num = i; | |
24d2f903 CH |
1599 | hctx->flags = set->flags; |
1600 | hctx->cmd_size = set->cmd_size; | |
320ae51f JA |
1601 | |
1602 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1603 | blk_mq_hctx_notify, hctx); | |
1604 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1605 | ||
24d2f903 | 1606 | hctx->tags = set->tags[i]; |
320ae51f JA |
1607 | |
1608 | /* | |
a68aafa5 | 1609 | * Allocate space for all possible cpus to avoid allocation at |
320ae51f JA |
1610 | * runtime |
1611 | */ | |
1612 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), | |
1613 | GFP_KERNEL, node); | |
1614 | if (!hctx->ctxs) | |
1615 | break; | |
1616 | ||
1429d7c9 | 1617 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
320ae51f JA |
1618 | break; |
1619 | ||
320ae51f JA |
1620 | hctx->nr_ctx = 0; |
1621 | ||
24d2f903 CH |
1622 | if (set->ops->init_hctx && |
1623 | set->ops->init_hctx(hctx, set->driver_data, i)) | |
320ae51f JA |
1624 | break; |
1625 | } | |
1626 | ||
1627 | if (i == q->nr_hw_queues) | |
1628 | return 0; | |
1629 | ||
1630 | /* | |
1631 | * Init failed | |
1632 | */ | |
624dbe47 | 1633 | blk_mq_exit_hw_queues(q, set, i); |
320ae51f JA |
1634 | |
1635 | return 1; | |
1636 | } | |
1637 | ||
1638 | static void blk_mq_init_cpu_queues(struct request_queue *q, | |
1639 | unsigned int nr_hw_queues) | |
1640 | { | |
1641 | unsigned int i; | |
1642 | ||
1643 | for_each_possible_cpu(i) { | |
1644 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1645 | struct blk_mq_hw_ctx *hctx; | |
1646 | ||
1647 | memset(__ctx, 0, sizeof(*__ctx)); | |
1648 | __ctx->cpu = i; | |
1649 | spin_lock_init(&__ctx->lock); | |
1650 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1651 | __ctx->queue = q; | |
1652 | ||
1653 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1654 | if (!cpu_online(i)) |
1655 | continue; | |
1656 | ||
e4043dcf JA |
1657 | hctx = q->mq_ops->map_queue(q, i); |
1658 | cpumask_set_cpu(i, hctx->cpumask); | |
1659 | hctx->nr_ctx++; | |
1660 | ||
320ae51f JA |
1661 | /* |
1662 | * Set local node, IFF we have more than one hw queue. If | |
1663 | * not, we remain on the home node of the device | |
1664 | */ | |
1665 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
1666 | hctx->numa_node = cpu_to_node(i); | |
1667 | } | |
1668 | } | |
1669 | ||
1670 | static void blk_mq_map_swqueue(struct request_queue *q) | |
1671 | { | |
1672 | unsigned int i; | |
1673 | struct blk_mq_hw_ctx *hctx; | |
1674 | struct blk_mq_ctx *ctx; | |
1675 | ||
1676 | queue_for_each_hw_ctx(q, hctx, i) { | |
e4043dcf | 1677 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1678 | hctx->nr_ctx = 0; |
1679 | } | |
1680 | ||
1681 | /* | |
1682 | * Map software to hardware queues | |
1683 | */ | |
1684 | queue_for_each_ctx(q, ctx, i) { | |
1685 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
e4043dcf JA |
1686 | if (!cpu_online(i)) |
1687 | continue; | |
1688 | ||
320ae51f | 1689 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1690 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1691 | ctx->index_hw = hctx->nr_ctx; |
1692 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1693 | } | |
506e931f JA |
1694 | |
1695 | queue_for_each_hw_ctx(q, hctx, i) { | |
484b4061 | 1696 | /* |
a68aafa5 JA |
1697 | * If no software queues are mapped to this hardware queue, |
1698 | * disable it and free the request entries. | |
484b4061 JA |
1699 | */ |
1700 | if (!hctx->nr_ctx) { | |
1701 | struct blk_mq_tag_set *set = q->tag_set; | |
1702 | ||
1703 | if (set->tags[i]) { | |
1704 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1705 | set->tags[i] = NULL; | |
1706 | hctx->tags = NULL; | |
1707 | } | |
1708 | continue; | |
1709 | } | |
1710 | ||
1711 | /* | |
1712 | * Initialize batch roundrobin counts | |
1713 | */ | |
506e931f JA |
1714 | hctx->next_cpu = cpumask_first(hctx->cpumask); |
1715 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1716 | } | |
320ae51f JA |
1717 | } |
1718 | ||
0d2602ca JA |
1719 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |
1720 | { | |
1721 | struct blk_mq_hw_ctx *hctx; | |
1722 | struct request_queue *q; | |
1723 | bool shared; | |
1724 | int i; | |
1725 | ||
1726 | if (set->tag_list.next == set->tag_list.prev) | |
1727 | shared = false; | |
1728 | else | |
1729 | shared = true; | |
1730 | ||
1731 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1732 | blk_mq_freeze_queue(q); | |
1733 | ||
1734 | queue_for_each_hw_ctx(q, hctx, i) { | |
1735 | if (shared) | |
1736 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1737 | else | |
1738 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1739 | } | |
1740 | blk_mq_unfreeze_queue(q); | |
1741 | } | |
1742 | } | |
1743 | ||
1744 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1745 | { | |
1746 | struct blk_mq_tag_set *set = q->tag_set; | |
1747 | ||
0d2602ca JA |
1748 | mutex_lock(&set->tag_list_lock); |
1749 | list_del_init(&q->tag_set_list); | |
1750 | blk_mq_update_tag_set_depth(set); | |
1751 | mutex_unlock(&set->tag_list_lock); | |
0d2602ca JA |
1752 | } |
1753 | ||
1754 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1755 | struct request_queue *q) | |
1756 | { | |
1757 | q->tag_set = set; | |
1758 | ||
1759 | mutex_lock(&set->tag_list_lock); | |
1760 | list_add_tail(&q->tag_set_list, &set->tag_list); | |
1761 | blk_mq_update_tag_set_depth(set); | |
1762 | mutex_unlock(&set->tag_list_lock); | |
1763 | } | |
1764 | ||
24d2f903 | 1765 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
320ae51f JA |
1766 | { |
1767 | struct blk_mq_hw_ctx **hctxs; | |
e6cdb092 | 1768 | struct blk_mq_ctx __percpu *ctx; |
320ae51f | 1769 | struct request_queue *q; |
f14bbe77 | 1770 | unsigned int *map; |
320ae51f JA |
1771 | int i; |
1772 | ||
320ae51f JA |
1773 | ctx = alloc_percpu(struct blk_mq_ctx); |
1774 | if (!ctx) | |
1775 | return ERR_PTR(-ENOMEM); | |
1776 | ||
24d2f903 CH |
1777 | hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, |
1778 | set->numa_node); | |
320ae51f JA |
1779 | |
1780 | if (!hctxs) | |
1781 | goto err_percpu; | |
1782 | ||
f14bbe77 JA |
1783 | map = blk_mq_make_queue_map(set); |
1784 | if (!map) | |
1785 | goto err_map; | |
1786 | ||
24d2f903 | 1787 | for (i = 0; i < set->nr_hw_queues; i++) { |
f14bbe77 JA |
1788 | int node = blk_mq_hw_queue_to_node(map, i); |
1789 | ||
cdef54dd CH |
1790 | hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), |
1791 | GFP_KERNEL, node); | |
320ae51f JA |
1792 | if (!hctxs[i]) |
1793 | goto err_hctxs; | |
1794 | ||
e4043dcf JA |
1795 | if (!zalloc_cpumask_var(&hctxs[i]->cpumask, GFP_KERNEL)) |
1796 | goto err_hctxs; | |
1797 | ||
0d2602ca | 1798 | atomic_set(&hctxs[i]->nr_active, 0); |
f14bbe77 | 1799 | hctxs[i]->numa_node = node; |
320ae51f JA |
1800 | hctxs[i]->queue_num = i; |
1801 | } | |
1802 | ||
24d2f903 | 1803 | q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); |
320ae51f JA |
1804 | if (!q) |
1805 | goto err_hctxs; | |
1806 | ||
add703fd | 1807 | if (percpu_ref_init(&q->mq_usage_counter, blk_mq_usage_counter_release)) |
3d2936f4 ML |
1808 | goto err_map; |
1809 | ||
320ae51f JA |
1810 | setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); |
1811 | blk_queue_rq_timeout(q, 30000); | |
1812 | ||
1813 | q->nr_queues = nr_cpu_ids; | |
24d2f903 | 1814 | q->nr_hw_queues = set->nr_hw_queues; |
f14bbe77 | 1815 | q->mq_map = map; |
320ae51f JA |
1816 | |
1817 | q->queue_ctx = ctx; | |
1818 | q->queue_hw_ctx = hctxs; | |
1819 | ||
24d2f903 | 1820 | q->mq_ops = set->ops; |
94eddfbe | 1821 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 1822 | |
05f1dd53 JA |
1823 | if (!(set->flags & BLK_MQ_F_SG_MERGE)) |
1824 | q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; | |
1825 | ||
1be036e9 CH |
1826 | q->sg_reserved_size = INT_MAX; |
1827 | ||
6fca6a61 CH |
1828 | INIT_WORK(&q->requeue_work, blk_mq_requeue_work); |
1829 | INIT_LIST_HEAD(&q->requeue_list); | |
1830 | spin_lock_init(&q->requeue_lock); | |
1831 | ||
07068d5b JA |
1832 | if (q->nr_hw_queues > 1) |
1833 | blk_queue_make_request(q, blk_mq_make_request); | |
1834 | else | |
1835 | blk_queue_make_request(q, blk_sq_make_request); | |
1836 | ||
87ee7b11 | 1837 | blk_queue_rq_timed_out(q, blk_mq_rq_timed_out); |
24d2f903 CH |
1838 | if (set->timeout) |
1839 | blk_queue_rq_timeout(q, set->timeout); | |
320ae51f | 1840 | |
eba71768 JA |
1841 | /* |
1842 | * Do this after blk_queue_make_request() overrides it... | |
1843 | */ | |
1844 | q->nr_requests = set->queue_depth; | |
1845 | ||
24d2f903 CH |
1846 | if (set->ops->complete) |
1847 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 1848 | |
320ae51f | 1849 | blk_mq_init_flush(q); |
24d2f903 | 1850 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 1851 | |
24d2f903 CH |
1852 | q->flush_rq = kzalloc(round_up(sizeof(struct request) + |
1853 | set->cmd_size, cache_line_size()), | |
1854 | GFP_KERNEL); | |
18741986 | 1855 | if (!q->flush_rq) |
320ae51f JA |
1856 | goto err_hw; |
1857 | ||
24d2f903 | 1858 | if (blk_mq_init_hw_queues(q, set)) |
18741986 CH |
1859 | goto err_flush_rq; |
1860 | ||
320ae51f JA |
1861 | mutex_lock(&all_q_mutex); |
1862 | list_add_tail(&q->all_q_node, &all_q_list); | |
1863 | mutex_unlock(&all_q_mutex); | |
1864 | ||
0d2602ca JA |
1865 | blk_mq_add_queue_tag_set(set, q); |
1866 | ||
484b4061 JA |
1867 | blk_mq_map_swqueue(q); |
1868 | ||
320ae51f | 1869 | return q; |
18741986 CH |
1870 | |
1871 | err_flush_rq: | |
1872 | kfree(q->flush_rq); | |
320ae51f | 1873 | err_hw: |
320ae51f JA |
1874 | blk_cleanup_queue(q); |
1875 | err_hctxs: | |
f14bbe77 | 1876 | kfree(map); |
24d2f903 | 1877 | for (i = 0; i < set->nr_hw_queues; i++) { |
320ae51f JA |
1878 | if (!hctxs[i]) |
1879 | break; | |
e4043dcf | 1880 | free_cpumask_var(hctxs[i]->cpumask); |
cdef54dd | 1881 | kfree(hctxs[i]); |
320ae51f | 1882 | } |
f14bbe77 | 1883 | err_map: |
320ae51f JA |
1884 | kfree(hctxs); |
1885 | err_percpu: | |
1886 | free_percpu(ctx); | |
1887 | return ERR_PTR(-ENOMEM); | |
1888 | } | |
1889 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1890 | ||
1891 | void blk_mq_free_queue(struct request_queue *q) | |
1892 | { | |
624dbe47 | 1893 | struct blk_mq_tag_set *set = q->tag_set; |
320ae51f | 1894 | |
0d2602ca JA |
1895 | blk_mq_del_queue_tag_set(q); |
1896 | ||
624dbe47 ML |
1897 | blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); |
1898 | blk_mq_free_hw_queues(q, set); | |
320ae51f | 1899 | |
add703fd | 1900 | percpu_ref_exit(&q->mq_usage_counter); |
3d2936f4 | 1901 | |
320ae51f JA |
1902 | free_percpu(q->queue_ctx); |
1903 | kfree(q->queue_hw_ctx); | |
1904 | kfree(q->mq_map); | |
1905 | ||
1906 | q->queue_ctx = NULL; | |
1907 | q->queue_hw_ctx = NULL; | |
1908 | q->mq_map = NULL; | |
1909 | ||
1910 | mutex_lock(&all_q_mutex); | |
1911 | list_del_init(&q->all_q_node); | |
1912 | mutex_unlock(&all_q_mutex); | |
1913 | } | |
320ae51f JA |
1914 | |
1915 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
f618ef7c | 1916 | static void blk_mq_queue_reinit(struct request_queue *q) |
320ae51f JA |
1917 | { |
1918 | blk_mq_freeze_queue(q); | |
1919 | ||
67aec14c JA |
1920 | blk_mq_sysfs_unregister(q); |
1921 | ||
320ae51f JA |
1922 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues); |
1923 | ||
1924 | /* | |
1925 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
1926 | * we should change hctx numa_node according to new topology (this | |
1927 | * involves free and re-allocate memory, worthy doing?) | |
1928 | */ | |
1929 | ||
1930 | blk_mq_map_swqueue(q); | |
1931 | ||
67aec14c JA |
1932 | blk_mq_sysfs_register(q); |
1933 | ||
320ae51f JA |
1934 | blk_mq_unfreeze_queue(q); |
1935 | } | |
1936 | ||
f618ef7c PG |
1937 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
1938 | unsigned long action, void *hcpu) | |
320ae51f JA |
1939 | { |
1940 | struct request_queue *q; | |
1941 | ||
1942 | /* | |
9fccfed8 JA |
1943 | * Before new mappings are established, hotadded cpu might already |
1944 | * start handling requests. This doesn't break anything as we map | |
1945 | * offline CPUs to first hardware queue. We will re-init the queue | |
1946 | * below to get optimal settings. | |
320ae51f JA |
1947 | */ |
1948 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN && | |
1949 | action != CPU_ONLINE && action != CPU_ONLINE_FROZEN) | |
1950 | return NOTIFY_OK; | |
1951 | ||
1952 | mutex_lock(&all_q_mutex); | |
1953 | list_for_each_entry(q, &all_q_list, all_q_node) | |
1954 | blk_mq_queue_reinit(q); | |
1955 | mutex_unlock(&all_q_mutex); | |
1956 | return NOTIFY_OK; | |
1957 | } | |
1958 | ||
a5164405 JA |
1959 | static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) |
1960 | { | |
1961 | int i; | |
1962 | ||
1963 | for (i = 0; i < set->nr_hw_queues; i++) { | |
1964 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1965 | if (!set->tags[i]) | |
1966 | goto out_unwind; | |
1967 | } | |
1968 | ||
1969 | return 0; | |
1970 | ||
1971 | out_unwind: | |
1972 | while (--i >= 0) | |
1973 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1974 | ||
a5164405 JA |
1975 | return -ENOMEM; |
1976 | } | |
1977 | ||
1978 | /* | |
1979 | * Allocate the request maps associated with this tag_set. Note that this | |
1980 | * may reduce the depth asked for, if memory is tight. set->queue_depth | |
1981 | * will be updated to reflect the allocated depth. | |
1982 | */ | |
1983 | static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) | |
1984 | { | |
1985 | unsigned int depth; | |
1986 | int err; | |
1987 | ||
1988 | depth = set->queue_depth; | |
1989 | do { | |
1990 | err = __blk_mq_alloc_rq_maps(set); | |
1991 | if (!err) | |
1992 | break; | |
1993 | ||
1994 | set->queue_depth >>= 1; | |
1995 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) { | |
1996 | err = -ENOMEM; | |
1997 | break; | |
1998 | } | |
1999 | } while (set->queue_depth); | |
2000 | ||
2001 | if (!set->queue_depth || err) { | |
2002 | pr_err("blk-mq: failed to allocate request map\n"); | |
2003 | return -ENOMEM; | |
2004 | } | |
2005 | ||
2006 | if (depth != set->queue_depth) | |
2007 | pr_info("blk-mq: reduced tag depth (%u -> %u)\n", | |
2008 | depth, set->queue_depth); | |
2009 | ||
2010 | return 0; | |
2011 | } | |
2012 | ||
a4391c64 JA |
2013 | /* |
2014 | * Alloc a tag set to be associated with one or more request queues. | |
2015 | * May fail with EINVAL for various error conditions. May adjust the | |
2016 | * requested depth down, if if it too large. In that case, the set | |
2017 | * value will be stored in set->queue_depth. | |
2018 | */ | |
24d2f903 CH |
2019 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
2020 | { | |
24d2f903 CH |
2021 | if (!set->nr_hw_queues) |
2022 | return -EINVAL; | |
a4391c64 | 2023 | if (!set->queue_depth) |
24d2f903 CH |
2024 | return -EINVAL; |
2025 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
2026 | return -EINVAL; | |
2027 | ||
cdef54dd | 2028 | if (!set->nr_hw_queues || !set->ops->queue_rq || !set->ops->map_queue) |
24d2f903 CH |
2029 | return -EINVAL; |
2030 | ||
a4391c64 JA |
2031 | if (set->queue_depth > BLK_MQ_MAX_DEPTH) { |
2032 | pr_info("blk-mq: reduced tag depth to %u\n", | |
2033 | BLK_MQ_MAX_DEPTH); | |
2034 | set->queue_depth = BLK_MQ_MAX_DEPTH; | |
2035 | } | |
24d2f903 | 2036 | |
48479005 ML |
2037 | set->tags = kmalloc_node(set->nr_hw_queues * |
2038 | sizeof(struct blk_mq_tags *), | |
24d2f903 CH |
2039 | GFP_KERNEL, set->numa_node); |
2040 | if (!set->tags) | |
a5164405 | 2041 | return -ENOMEM; |
24d2f903 | 2042 | |
a5164405 JA |
2043 | if (blk_mq_alloc_rq_maps(set)) |
2044 | goto enomem; | |
24d2f903 | 2045 | |
0d2602ca JA |
2046 | mutex_init(&set->tag_list_lock); |
2047 | INIT_LIST_HEAD(&set->tag_list); | |
2048 | ||
24d2f903 | 2049 | return 0; |
a5164405 | 2050 | enomem: |
5676e7b6 RE |
2051 | kfree(set->tags); |
2052 | set->tags = NULL; | |
24d2f903 CH |
2053 | return -ENOMEM; |
2054 | } | |
2055 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
2056 | ||
2057 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
2058 | { | |
2059 | int i; | |
2060 | ||
484b4061 JA |
2061 | for (i = 0; i < set->nr_hw_queues; i++) { |
2062 | if (set->tags[i]) | |
2063 | blk_mq_free_rq_map(set, set->tags[i], i); | |
2064 | } | |
2065 | ||
981bd189 | 2066 | kfree(set->tags); |
5676e7b6 | 2067 | set->tags = NULL; |
24d2f903 CH |
2068 | } |
2069 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
2070 | ||
e3a2b3f9 JA |
2071 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
2072 | { | |
2073 | struct blk_mq_tag_set *set = q->tag_set; | |
2074 | struct blk_mq_hw_ctx *hctx; | |
2075 | int i, ret; | |
2076 | ||
2077 | if (!set || nr > set->queue_depth) | |
2078 | return -EINVAL; | |
2079 | ||
2080 | ret = 0; | |
2081 | queue_for_each_hw_ctx(q, hctx, i) { | |
2082 | ret = blk_mq_tag_update_depth(hctx->tags, nr); | |
2083 | if (ret) | |
2084 | break; | |
2085 | } | |
2086 | ||
2087 | if (!ret) | |
2088 | q->nr_requests = nr; | |
2089 | ||
2090 | return ret; | |
2091 | } | |
2092 | ||
676141e4 JA |
2093 | void blk_mq_disable_hotplug(void) |
2094 | { | |
2095 | mutex_lock(&all_q_mutex); | |
2096 | } | |
2097 | ||
2098 | void blk_mq_enable_hotplug(void) | |
2099 | { | |
2100 | mutex_unlock(&all_q_mutex); | |
2101 | } | |
2102 | ||
320ae51f JA |
2103 | static int __init blk_mq_init(void) |
2104 | { | |
320ae51f JA |
2105 | blk_mq_cpu_init(); |
2106 | ||
add703fd | 2107 | hotcpu_notifier(blk_mq_queue_reinit_notify, 0); |
320ae51f JA |
2108 | |
2109 | return 0; | |
2110 | } | |
2111 | subsys_initcall(blk_mq_init); |