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320ae51f JA |
1 | #include <linux/kernel.h> |
2 | #include <linux/module.h> | |
3 | #include <linux/backing-dev.h> | |
4 | #include <linux/bio.h> | |
5 | #include <linux/blkdev.h> | |
6 | #include <linux/mm.h> | |
7 | #include <linux/init.h> | |
8 | #include <linux/slab.h> | |
9 | #include <linux/workqueue.h> | |
10 | #include <linux/smp.h> | |
11 | #include <linux/llist.h> | |
12 | #include <linux/list_sort.h> | |
13 | #include <linux/cpu.h> | |
14 | #include <linux/cache.h> | |
15 | #include <linux/sched/sysctl.h> | |
16 | #include <linux/delay.h> | |
17 | ||
18 | #include <trace/events/block.h> | |
19 | ||
20 | #include <linux/blk-mq.h> | |
21 | #include "blk.h" | |
22 | #include "blk-mq.h" | |
23 | #include "blk-mq-tag.h" | |
24 | ||
25 | static DEFINE_MUTEX(all_q_mutex); | |
26 | static LIST_HEAD(all_q_list); | |
27 | ||
28 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx); | |
29 | ||
320ae51f JA |
30 | static struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q, |
31 | unsigned int cpu) | |
32 | { | |
33 | return per_cpu_ptr(q->queue_ctx, cpu); | |
34 | } | |
35 | ||
36 | /* | |
37 | * This assumes per-cpu software queueing queues. They could be per-node | |
38 | * as well, for instance. For now this is hardcoded as-is. Note that we don't | |
39 | * care about preemption, since we know the ctx's are persistent. This does | |
40 | * mean that we can't rely on ctx always matching the currently running CPU. | |
41 | */ | |
42 | static struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q) | |
43 | { | |
44 | return __blk_mq_get_ctx(q, get_cpu()); | |
45 | } | |
46 | ||
47 | static void blk_mq_put_ctx(struct blk_mq_ctx *ctx) | |
48 | { | |
49 | put_cpu(); | |
50 | } | |
51 | ||
52 | /* | |
53 | * Check if any of the ctx's have pending work in this hardware queue | |
54 | */ | |
55 | static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx) | |
56 | { | |
57 | unsigned int i; | |
58 | ||
1429d7c9 JA |
59 | for (i = 0; i < hctx->ctx_map.map_size; i++) |
60 | if (hctx->ctx_map.map[i].word) | |
320ae51f JA |
61 | return true; |
62 | ||
63 | return false; | |
64 | } | |
65 | ||
1429d7c9 JA |
66 | static inline struct blk_align_bitmap *get_bm(struct blk_mq_hw_ctx *hctx, |
67 | struct blk_mq_ctx *ctx) | |
68 | { | |
69 | return &hctx->ctx_map.map[ctx->index_hw / hctx->ctx_map.bits_per_word]; | |
70 | } | |
71 | ||
72 | #define CTX_TO_BIT(hctx, ctx) \ | |
73 | ((ctx)->index_hw & ((hctx)->ctx_map.bits_per_word - 1)) | |
74 | ||
320ae51f JA |
75 | /* |
76 | * Mark this ctx as having pending work in this hardware queue | |
77 | */ | |
78 | static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, | |
79 | struct blk_mq_ctx *ctx) | |
80 | { | |
1429d7c9 JA |
81 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); |
82 | ||
83 | if (!test_bit(CTX_TO_BIT(hctx, ctx), &bm->word)) | |
84 | set_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
85 | } | |
86 | ||
87 | static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, | |
88 | struct blk_mq_ctx *ctx) | |
89 | { | |
90 | struct blk_align_bitmap *bm = get_bm(hctx, ctx); | |
91 | ||
92 | clear_bit(CTX_TO_BIT(hctx, ctx), &bm->word); | |
320ae51f JA |
93 | } |
94 | ||
081241e5 | 95 | static struct request *__blk_mq_alloc_request(struct blk_mq_hw_ctx *hctx, |
4bb659b1 | 96 | struct blk_mq_ctx *ctx, |
081241e5 | 97 | gfp_t gfp, bool reserved) |
320ae51f JA |
98 | { |
99 | struct request *rq; | |
100 | unsigned int tag; | |
101 | ||
0d2602ca | 102 | tag = blk_mq_get_tag(hctx, &ctx->last_tag, gfp, reserved); |
320ae51f | 103 | if (tag != BLK_MQ_TAG_FAIL) { |
24d2f903 | 104 | rq = hctx->tags->rqs[tag]; |
0d2602ca JA |
105 | |
106 | rq->cmd_flags = 0; | |
107 | if (blk_mq_tag_busy(hctx)) { | |
108 | rq->cmd_flags = REQ_MQ_INFLIGHT; | |
109 | atomic_inc(&hctx->nr_active); | |
110 | } | |
111 | ||
320ae51f | 112 | rq->tag = tag; |
320ae51f JA |
113 | return rq; |
114 | } | |
115 | ||
116 | return NULL; | |
117 | } | |
118 | ||
119 | static int blk_mq_queue_enter(struct request_queue *q) | |
120 | { | |
121 | int ret; | |
122 | ||
123 | __percpu_counter_add(&q->mq_usage_counter, 1, 1000000); | |
124 | smp_wmb(); | |
125 | /* we have problems to freeze the queue if it's initializing */ | |
126 | if (!blk_queue_bypass(q) || !blk_queue_init_done(q)) | |
127 | return 0; | |
128 | ||
129 | __percpu_counter_add(&q->mq_usage_counter, -1, 1000000); | |
130 | ||
131 | spin_lock_irq(q->queue_lock); | |
132 | ret = wait_event_interruptible_lock_irq(q->mq_freeze_wq, | |
43a5e4e2 ML |
133 | !blk_queue_bypass(q) || blk_queue_dying(q), |
134 | *q->queue_lock); | |
320ae51f | 135 | /* inc usage with lock hold to avoid freeze_queue runs here */ |
43a5e4e2 | 136 | if (!ret && !blk_queue_dying(q)) |
320ae51f | 137 | __percpu_counter_add(&q->mq_usage_counter, 1, 1000000); |
43a5e4e2 ML |
138 | else if (blk_queue_dying(q)) |
139 | ret = -ENODEV; | |
320ae51f JA |
140 | spin_unlock_irq(q->queue_lock); |
141 | ||
142 | return ret; | |
143 | } | |
144 | ||
145 | static void blk_mq_queue_exit(struct request_queue *q) | |
146 | { | |
147 | __percpu_counter_add(&q->mq_usage_counter, -1, 1000000); | |
148 | } | |
149 | ||
43a5e4e2 ML |
150 | static void __blk_mq_drain_queue(struct request_queue *q) |
151 | { | |
152 | while (true) { | |
153 | s64 count; | |
154 | ||
155 | spin_lock_irq(q->queue_lock); | |
156 | count = percpu_counter_sum(&q->mq_usage_counter); | |
157 | spin_unlock_irq(q->queue_lock); | |
158 | ||
159 | if (count == 0) | |
160 | break; | |
161 | blk_mq_run_queues(q, false); | |
162 | msleep(10); | |
163 | } | |
164 | } | |
165 | ||
320ae51f JA |
166 | /* |
167 | * Guarantee no request is in use, so we can change any data structure of | |
168 | * the queue afterward. | |
169 | */ | |
170 | static void blk_mq_freeze_queue(struct request_queue *q) | |
171 | { | |
172 | bool drain; | |
173 | ||
174 | spin_lock_irq(q->queue_lock); | |
175 | drain = !q->bypass_depth++; | |
176 | queue_flag_set(QUEUE_FLAG_BYPASS, q); | |
177 | spin_unlock_irq(q->queue_lock); | |
178 | ||
43a5e4e2 ML |
179 | if (drain) |
180 | __blk_mq_drain_queue(q); | |
181 | } | |
320ae51f | 182 | |
43a5e4e2 ML |
183 | void blk_mq_drain_queue(struct request_queue *q) |
184 | { | |
185 | __blk_mq_drain_queue(q); | |
320ae51f JA |
186 | } |
187 | ||
188 | static void blk_mq_unfreeze_queue(struct request_queue *q) | |
189 | { | |
190 | bool wake = false; | |
191 | ||
192 | spin_lock_irq(q->queue_lock); | |
193 | if (!--q->bypass_depth) { | |
194 | queue_flag_clear(QUEUE_FLAG_BYPASS, q); | |
195 | wake = true; | |
196 | } | |
197 | WARN_ON_ONCE(q->bypass_depth < 0); | |
198 | spin_unlock_irq(q->queue_lock); | |
199 | if (wake) | |
200 | wake_up_all(&q->mq_freeze_wq); | |
201 | } | |
202 | ||
203 | bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) | |
204 | { | |
205 | return blk_mq_has_free_tags(hctx->tags); | |
206 | } | |
207 | EXPORT_SYMBOL(blk_mq_can_queue); | |
208 | ||
94eddfbe JA |
209 | static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, |
210 | struct request *rq, unsigned int rw_flags) | |
320ae51f | 211 | { |
94eddfbe JA |
212 | if (blk_queue_io_stat(q)) |
213 | rw_flags |= REQ_IO_STAT; | |
214 | ||
af76e555 CH |
215 | INIT_LIST_HEAD(&rq->queuelist); |
216 | /* csd/requeue_work/fifo_time is initialized before use */ | |
217 | rq->q = q; | |
320ae51f | 218 | rq->mq_ctx = ctx; |
0d2602ca | 219 | rq->cmd_flags |= rw_flags; |
af76e555 CH |
220 | rq->cmd_type = 0; |
221 | /* do not touch atomic flags, it needs atomic ops against the timer */ | |
222 | rq->cpu = -1; | |
223 | rq->__data_len = 0; | |
224 | rq->__sector = (sector_t) -1; | |
225 | rq->bio = NULL; | |
226 | rq->biotail = NULL; | |
227 | INIT_HLIST_NODE(&rq->hash); | |
228 | RB_CLEAR_NODE(&rq->rb_node); | |
229 | memset(&rq->flush, 0, max(sizeof(rq->flush), sizeof(rq->elv))); | |
230 | rq->rq_disk = NULL; | |
231 | rq->part = NULL; | |
0fec08b4 | 232 | rq->start_time = jiffies; |
af76e555 CH |
233 | #ifdef CONFIG_BLK_CGROUP |
234 | rq->rl = NULL; | |
0fec08b4 | 235 | set_start_time_ns(rq); |
af76e555 CH |
236 | rq->io_start_time_ns = 0; |
237 | #endif | |
238 | rq->nr_phys_segments = 0; | |
239 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
240 | rq->nr_integrity_segments = 0; | |
241 | #endif | |
242 | rq->ioprio = 0; | |
243 | rq->special = NULL; | |
244 | /* tag was already set */ | |
245 | rq->errors = 0; | |
246 | memset(rq->__cmd, 0, sizeof(rq->__cmd)); | |
247 | rq->cmd = rq->__cmd; | |
248 | rq->cmd_len = BLK_MAX_CDB; | |
249 | ||
250 | rq->extra_len = 0; | |
251 | rq->sense_len = 0; | |
252 | rq->resid_len = 0; | |
253 | rq->sense = NULL; | |
254 | ||
255 | rq->deadline = 0; | |
256 | INIT_LIST_HEAD(&rq->timeout_list); | |
257 | rq->timeout = 0; | |
258 | rq->retries = 0; | |
259 | rq->end_io = NULL; | |
260 | rq->end_io_data = NULL; | |
261 | rq->next_rq = NULL; | |
262 | ||
320ae51f JA |
263 | ctx->rq_dispatched[rw_is_sync(rw_flags)]++; |
264 | } | |
265 | ||
320ae51f JA |
266 | static struct request *blk_mq_alloc_request_pinned(struct request_queue *q, |
267 | int rw, gfp_t gfp, | |
268 | bool reserved) | |
269 | { | |
270 | struct request *rq; | |
271 | ||
272 | do { | |
273 | struct blk_mq_ctx *ctx = blk_mq_get_ctx(q); | |
274 | struct blk_mq_hw_ctx *hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
275 | ||
4bb659b1 JA |
276 | rq = __blk_mq_alloc_request(hctx, ctx, gfp & ~__GFP_WAIT, |
277 | reserved); | |
320ae51f | 278 | if (rq) { |
94eddfbe | 279 | blk_mq_rq_ctx_init(q, ctx, rq, rw); |
320ae51f | 280 | break; |
959a35f1 | 281 | } |
320ae51f | 282 | |
e4043dcf JA |
283 | if (gfp & __GFP_WAIT) { |
284 | __blk_mq_run_hw_queue(hctx); | |
285 | blk_mq_put_ctx(ctx); | |
286 | } else { | |
287 | blk_mq_put_ctx(ctx); | |
959a35f1 | 288 | break; |
e4043dcf | 289 | } |
959a35f1 | 290 | |
0d2602ca | 291 | blk_mq_wait_for_tags(hctx, reserved); |
320ae51f JA |
292 | } while (1); |
293 | ||
294 | return rq; | |
295 | } | |
296 | ||
18741986 | 297 | struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp) |
320ae51f JA |
298 | { |
299 | struct request *rq; | |
300 | ||
301 | if (blk_mq_queue_enter(q)) | |
302 | return NULL; | |
303 | ||
18741986 | 304 | rq = blk_mq_alloc_request_pinned(q, rw, gfp, false); |
959a35f1 JM |
305 | if (rq) |
306 | blk_mq_put_ctx(rq->mq_ctx); | |
320ae51f JA |
307 | return rq; |
308 | } | |
4bb659b1 | 309 | EXPORT_SYMBOL(blk_mq_alloc_request); |
320ae51f JA |
310 | |
311 | struct request *blk_mq_alloc_reserved_request(struct request_queue *q, int rw, | |
312 | gfp_t gfp) | |
313 | { | |
314 | struct request *rq; | |
315 | ||
316 | if (blk_mq_queue_enter(q)) | |
317 | return NULL; | |
318 | ||
319 | rq = blk_mq_alloc_request_pinned(q, rw, gfp, true); | |
959a35f1 JM |
320 | if (rq) |
321 | blk_mq_put_ctx(rq->mq_ctx); | |
320ae51f JA |
322 | return rq; |
323 | } | |
324 | EXPORT_SYMBOL(blk_mq_alloc_reserved_request); | |
325 | ||
320ae51f JA |
326 | static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, |
327 | struct blk_mq_ctx *ctx, struct request *rq) | |
328 | { | |
329 | const int tag = rq->tag; | |
330 | struct request_queue *q = rq->q; | |
331 | ||
0d2602ca JA |
332 | if (rq->cmd_flags & REQ_MQ_INFLIGHT) |
333 | atomic_dec(&hctx->nr_active); | |
334 | ||
af76e555 | 335 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
0d2602ca | 336 | blk_mq_put_tag(hctx, tag, &ctx->last_tag); |
320ae51f JA |
337 | blk_mq_queue_exit(q); |
338 | } | |
339 | ||
340 | void blk_mq_free_request(struct request *rq) | |
341 | { | |
342 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
343 | struct blk_mq_hw_ctx *hctx; | |
344 | struct request_queue *q = rq->q; | |
345 | ||
346 | ctx->rq_completed[rq_is_sync(rq)]++; | |
347 | ||
348 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
349 | __blk_mq_free_request(hctx, ctx, rq); | |
350 | } | |
351 | ||
8727af4b CH |
352 | /* |
353 | * Clone all relevant state from a request that has been put on hold in | |
354 | * the flush state machine into the preallocated flush request that hangs | |
355 | * off the request queue. | |
356 | * | |
357 | * For a driver the flush request should be invisible, that's why we are | |
358 | * impersonating the original request here. | |
359 | */ | |
360 | void blk_mq_clone_flush_request(struct request *flush_rq, | |
361 | struct request *orig_rq) | |
362 | { | |
363 | struct blk_mq_hw_ctx *hctx = | |
364 | orig_rq->q->mq_ops->map_queue(orig_rq->q, orig_rq->mq_ctx->cpu); | |
365 | ||
366 | flush_rq->mq_ctx = orig_rq->mq_ctx; | |
367 | flush_rq->tag = orig_rq->tag; | |
368 | memcpy(blk_mq_rq_to_pdu(flush_rq), blk_mq_rq_to_pdu(orig_rq), | |
369 | hctx->cmd_size); | |
370 | } | |
371 | ||
63151a44 | 372 | inline void __blk_mq_end_io(struct request *rq, int error) |
320ae51f | 373 | { |
0d11e6ac ML |
374 | blk_account_io_done(rq); |
375 | ||
91b63639 | 376 | if (rq->end_io) { |
320ae51f | 377 | rq->end_io(rq, error); |
91b63639 CH |
378 | } else { |
379 | if (unlikely(blk_bidi_rq(rq))) | |
380 | blk_mq_free_request(rq->next_rq); | |
320ae51f | 381 | blk_mq_free_request(rq); |
91b63639 | 382 | } |
320ae51f | 383 | } |
63151a44 CH |
384 | EXPORT_SYMBOL(__blk_mq_end_io); |
385 | ||
386 | void blk_mq_end_io(struct request *rq, int error) | |
387 | { | |
388 | if (blk_update_request(rq, error, blk_rq_bytes(rq))) | |
389 | BUG(); | |
390 | __blk_mq_end_io(rq, error); | |
391 | } | |
392 | EXPORT_SYMBOL(blk_mq_end_io); | |
320ae51f | 393 | |
30a91cb4 | 394 | static void __blk_mq_complete_request_remote(void *data) |
320ae51f | 395 | { |
3d6efbf6 | 396 | struct request *rq = data; |
320ae51f | 397 | |
30a91cb4 | 398 | rq->q->softirq_done_fn(rq); |
320ae51f | 399 | } |
320ae51f | 400 | |
30a91cb4 | 401 | void __blk_mq_complete_request(struct request *rq) |
320ae51f JA |
402 | { |
403 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
38535201 | 404 | bool shared = false; |
320ae51f JA |
405 | int cpu; |
406 | ||
38535201 | 407 | if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { |
30a91cb4 CH |
408 | rq->q->softirq_done_fn(rq); |
409 | return; | |
410 | } | |
320ae51f JA |
411 | |
412 | cpu = get_cpu(); | |
38535201 CH |
413 | if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) |
414 | shared = cpus_share_cache(cpu, ctx->cpu); | |
415 | ||
416 | if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { | |
30a91cb4 | 417 | rq->csd.func = __blk_mq_complete_request_remote; |
3d6efbf6 CH |
418 | rq->csd.info = rq; |
419 | rq->csd.flags = 0; | |
c46fff2a | 420 | smp_call_function_single_async(ctx->cpu, &rq->csd); |
3d6efbf6 | 421 | } else { |
30a91cb4 | 422 | rq->q->softirq_done_fn(rq); |
3d6efbf6 | 423 | } |
320ae51f JA |
424 | put_cpu(); |
425 | } | |
30a91cb4 CH |
426 | |
427 | /** | |
428 | * blk_mq_complete_request - end I/O on a request | |
429 | * @rq: the request being processed | |
430 | * | |
431 | * Description: | |
432 | * Ends all I/O on a request. It does not handle partial completions. | |
433 | * The actual completion happens out-of-order, through a IPI handler. | |
434 | **/ | |
435 | void blk_mq_complete_request(struct request *rq) | |
436 | { | |
437 | if (unlikely(blk_should_fake_timeout(rq->q))) | |
438 | return; | |
439 | if (!blk_mark_rq_complete(rq)) | |
440 | __blk_mq_complete_request(rq); | |
441 | } | |
442 | EXPORT_SYMBOL(blk_mq_complete_request); | |
320ae51f | 443 | |
49f5baa5 | 444 | static void blk_mq_start_request(struct request *rq, bool last) |
320ae51f JA |
445 | { |
446 | struct request_queue *q = rq->q; | |
447 | ||
448 | trace_block_rq_issue(q, rq); | |
449 | ||
742ee69b | 450 | rq->resid_len = blk_rq_bytes(rq); |
91b63639 CH |
451 | if (unlikely(blk_bidi_rq(rq))) |
452 | rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); | |
742ee69b | 453 | |
320ae51f JA |
454 | /* |
455 | * Just mark start time and set the started bit. Due to memory | |
456 | * ordering, we know we'll see the correct deadline as long as | |
457 | * REQ_ATOMIC_STARTED is seen. | |
458 | */ | |
459 | rq->deadline = jiffies + q->rq_timeout; | |
87ee7b11 JA |
460 | |
461 | /* | |
462 | * Mark us as started and clear complete. Complete might have been | |
463 | * set if requeue raced with timeout, which then marked it as | |
464 | * complete. So be sure to clear complete again when we start | |
465 | * the request, otherwise we'll ignore the completion event. | |
466 | */ | |
320ae51f | 467 | set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); |
87ee7b11 | 468 | clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); |
49f5baa5 CH |
469 | |
470 | if (q->dma_drain_size && blk_rq_bytes(rq)) { | |
471 | /* | |
472 | * Make sure space for the drain appears. We know we can do | |
473 | * this because max_hw_segments has been adjusted to be one | |
474 | * fewer than the device can handle. | |
475 | */ | |
476 | rq->nr_phys_segments++; | |
477 | } | |
478 | ||
479 | /* | |
480 | * Flag the last request in the series so that drivers know when IO | |
481 | * should be kicked off, if they don't do it on a per-request basis. | |
482 | * | |
483 | * Note: the flag isn't the only condition drivers should do kick off. | |
484 | * If drive is busy, the last request might not have the bit set. | |
485 | */ | |
486 | if (last) | |
487 | rq->cmd_flags |= REQ_END; | |
320ae51f JA |
488 | } |
489 | ||
ed0791b2 | 490 | static void __blk_mq_requeue_request(struct request *rq) |
320ae51f JA |
491 | { |
492 | struct request_queue *q = rq->q; | |
493 | ||
494 | trace_block_rq_requeue(q, rq); | |
495 | clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); | |
49f5baa5 CH |
496 | |
497 | rq->cmd_flags &= ~REQ_END; | |
498 | ||
499 | if (q->dma_drain_size && blk_rq_bytes(rq)) | |
500 | rq->nr_phys_segments--; | |
320ae51f JA |
501 | } |
502 | ||
ed0791b2 CH |
503 | void blk_mq_requeue_request(struct request *rq) |
504 | { | |
ed0791b2 CH |
505 | __blk_mq_requeue_request(rq); |
506 | blk_clear_rq_complete(rq); | |
507 | ||
ed0791b2 CH |
508 | BUG_ON(blk_queued_rq(rq)); |
509 | blk_mq_insert_request(rq, true, true, false); | |
510 | } | |
511 | EXPORT_SYMBOL(blk_mq_requeue_request); | |
512 | ||
24d2f903 CH |
513 | struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) |
514 | { | |
515 | return tags->rqs[tag]; | |
516 | } | |
517 | EXPORT_SYMBOL(blk_mq_tag_to_rq); | |
518 | ||
320ae51f JA |
519 | struct blk_mq_timeout_data { |
520 | struct blk_mq_hw_ctx *hctx; | |
521 | unsigned long *next; | |
522 | unsigned int *next_set; | |
523 | }; | |
524 | ||
525 | static void blk_mq_timeout_check(void *__data, unsigned long *free_tags) | |
526 | { | |
527 | struct blk_mq_timeout_data *data = __data; | |
528 | struct blk_mq_hw_ctx *hctx = data->hctx; | |
529 | unsigned int tag; | |
530 | ||
531 | /* It may not be in flight yet (this is where | |
532 | * the REQ_ATOMIC_STARTED flag comes in). The requests are | |
533 | * statically allocated, so we know it's always safe to access the | |
534 | * memory associated with a bit offset into ->rqs[]. | |
535 | */ | |
536 | tag = 0; | |
537 | do { | |
538 | struct request *rq; | |
539 | ||
24d2f903 CH |
540 | tag = find_next_zero_bit(free_tags, hctx->tags->nr_tags, tag); |
541 | if (tag >= hctx->tags->nr_tags) | |
320ae51f JA |
542 | break; |
543 | ||
24d2f903 CH |
544 | rq = blk_mq_tag_to_rq(hctx->tags, tag++); |
545 | if (rq->q != hctx->queue) | |
546 | continue; | |
320ae51f JA |
547 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) |
548 | continue; | |
549 | ||
550 | blk_rq_check_expired(rq, data->next, data->next_set); | |
551 | } while (1); | |
552 | } | |
553 | ||
554 | static void blk_mq_hw_ctx_check_timeout(struct blk_mq_hw_ctx *hctx, | |
555 | unsigned long *next, | |
556 | unsigned int *next_set) | |
557 | { | |
558 | struct blk_mq_timeout_data data = { | |
559 | .hctx = hctx, | |
560 | .next = next, | |
561 | .next_set = next_set, | |
562 | }; | |
563 | ||
564 | /* | |
565 | * Ask the tagging code to iterate busy requests, so we can | |
566 | * check them for timeout. | |
567 | */ | |
568 | blk_mq_tag_busy_iter(hctx->tags, blk_mq_timeout_check, &data); | |
569 | } | |
570 | ||
87ee7b11 JA |
571 | static enum blk_eh_timer_return blk_mq_rq_timed_out(struct request *rq) |
572 | { | |
573 | struct request_queue *q = rq->q; | |
574 | ||
575 | /* | |
576 | * We know that complete is set at this point. If STARTED isn't set | |
577 | * anymore, then the request isn't active and the "timeout" should | |
578 | * just be ignored. This can happen due to the bitflag ordering. | |
579 | * Timeout first checks if STARTED is set, and if it is, assumes | |
580 | * the request is active. But if we race with completion, then | |
581 | * we both flags will get cleared. So check here again, and ignore | |
582 | * a timeout event with a request that isn't active. | |
583 | */ | |
584 | if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) | |
585 | return BLK_EH_NOT_HANDLED; | |
586 | ||
587 | if (!q->mq_ops->timeout) | |
588 | return BLK_EH_RESET_TIMER; | |
589 | ||
590 | return q->mq_ops->timeout(rq); | |
591 | } | |
592 | ||
320ae51f JA |
593 | static void blk_mq_rq_timer(unsigned long data) |
594 | { | |
595 | struct request_queue *q = (struct request_queue *) data; | |
596 | struct blk_mq_hw_ctx *hctx; | |
597 | unsigned long next = 0; | |
598 | int i, next_set = 0; | |
599 | ||
600 | queue_for_each_hw_ctx(q, hctx, i) | |
601 | blk_mq_hw_ctx_check_timeout(hctx, &next, &next_set); | |
602 | ||
0d2602ca JA |
603 | if (next_set) { |
604 | next = blk_rq_timeout(round_jiffies_up(next)); | |
605 | mod_timer(&q->timeout, next); | |
606 | } else { | |
607 | queue_for_each_hw_ctx(q, hctx, i) | |
608 | blk_mq_tag_idle(hctx); | |
609 | } | |
320ae51f JA |
610 | } |
611 | ||
612 | /* | |
613 | * Reverse check our software queue for entries that we could potentially | |
614 | * merge with. Currently includes a hand-wavy stop count of 8, to not spend | |
615 | * too much time checking for merges. | |
616 | */ | |
617 | static bool blk_mq_attempt_merge(struct request_queue *q, | |
618 | struct blk_mq_ctx *ctx, struct bio *bio) | |
619 | { | |
620 | struct request *rq; | |
621 | int checked = 8; | |
622 | ||
623 | list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { | |
624 | int el_ret; | |
625 | ||
626 | if (!checked--) | |
627 | break; | |
628 | ||
629 | if (!blk_rq_merge_ok(rq, bio)) | |
630 | continue; | |
631 | ||
632 | el_ret = blk_try_merge(rq, bio); | |
633 | if (el_ret == ELEVATOR_BACK_MERGE) { | |
634 | if (bio_attempt_back_merge(q, rq, bio)) { | |
635 | ctx->rq_merged++; | |
636 | return true; | |
637 | } | |
638 | break; | |
639 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { | |
640 | if (bio_attempt_front_merge(q, rq, bio)) { | |
641 | ctx->rq_merged++; | |
642 | return true; | |
643 | } | |
644 | break; | |
645 | } | |
646 | } | |
647 | ||
648 | return false; | |
649 | } | |
650 | ||
1429d7c9 JA |
651 | /* |
652 | * Process software queues that have been marked busy, splicing them | |
653 | * to the for-dispatch | |
654 | */ | |
655 | static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) | |
656 | { | |
657 | struct blk_mq_ctx *ctx; | |
658 | int i; | |
659 | ||
660 | for (i = 0; i < hctx->ctx_map.map_size; i++) { | |
661 | struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; | |
662 | unsigned int off, bit; | |
663 | ||
664 | if (!bm->word) | |
665 | continue; | |
666 | ||
667 | bit = 0; | |
668 | off = i * hctx->ctx_map.bits_per_word; | |
669 | do { | |
670 | bit = find_next_bit(&bm->word, bm->depth, bit); | |
671 | if (bit >= bm->depth) | |
672 | break; | |
673 | ||
674 | ctx = hctx->ctxs[bit + off]; | |
675 | clear_bit(bit, &bm->word); | |
676 | spin_lock(&ctx->lock); | |
677 | list_splice_tail_init(&ctx->rq_list, list); | |
678 | spin_unlock(&ctx->lock); | |
679 | ||
680 | bit++; | |
681 | } while (1); | |
682 | } | |
683 | } | |
684 | ||
320ae51f JA |
685 | /* |
686 | * Run this hardware queue, pulling any software queues mapped to it in. | |
687 | * Note that this function currently has various problems around ordering | |
688 | * of IO. In particular, we'd like FIFO behaviour on handling existing | |
689 | * items on the hctx->dispatch list. Ignore that for now. | |
690 | */ | |
691 | static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) | |
692 | { | |
693 | struct request_queue *q = hctx->queue; | |
320ae51f JA |
694 | struct request *rq; |
695 | LIST_HEAD(rq_list); | |
1429d7c9 | 696 | int queued; |
320ae51f | 697 | |
fd1270d5 | 698 | WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); |
e4043dcf | 699 | |
5d12f905 | 700 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
701 | return; |
702 | ||
703 | hctx->run++; | |
704 | ||
705 | /* | |
706 | * Touch any software queue that has pending entries. | |
707 | */ | |
1429d7c9 | 708 | flush_busy_ctxs(hctx, &rq_list); |
320ae51f JA |
709 | |
710 | /* | |
711 | * If we have previous entries on our dispatch list, grab them | |
712 | * and stuff them at the front for more fair dispatch. | |
713 | */ | |
714 | if (!list_empty_careful(&hctx->dispatch)) { | |
715 | spin_lock(&hctx->lock); | |
716 | if (!list_empty(&hctx->dispatch)) | |
717 | list_splice_init(&hctx->dispatch, &rq_list); | |
718 | spin_unlock(&hctx->lock); | |
719 | } | |
720 | ||
320ae51f JA |
721 | /* |
722 | * Now process all the entries, sending them to the driver. | |
723 | */ | |
1429d7c9 | 724 | queued = 0; |
320ae51f JA |
725 | while (!list_empty(&rq_list)) { |
726 | int ret; | |
727 | ||
728 | rq = list_first_entry(&rq_list, struct request, queuelist); | |
729 | list_del_init(&rq->queuelist); | |
320ae51f | 730 | |
49f5baa5 | 731 | blk_mq_start_request(rq, list_empty(&rq_list)); |
320ae51f JA |
732 | |
733 | ret = q->mq_ops->queue_rq(hctx, rq); | |
734 | switch (ret) { | |
735 | case BLK_MQ_RQ_QUEUE_OK: | |
736 | queued++; | |
737 | continue; | |
738 | case BLK_MQ_RQ_QUEUE_BUSY: | |
320ae51f | 739 | list_add(&rq->queuelist, &rq_list); |
ed0791b2 | 740 | __blk_mq_requeue_request(rq); |
320ae51f JA |
741 | break; |
742 | default: | |
743 | pr_err("blk-mq: bad return on queue: %d\n", ret); | |
320ae51f | 744 | case BLK_MQ_RQ_QUEUE_ERROR: |
1e93b8c2 | 745 | rq->errors = -EIO; |
320ae51f JA |
746 | blk_mq_end_io(rq, rq->errors); |
747 | break; | |
748 | } | |
749 | ||
750 | if (ret == BLK_MQ_RQ_QUEUE_BUSY) | |
751 | break; | |
752 | } | |
753 | ||
754 | if (!queued) | |
755 | hctx->dispatched[0]++; | |
756 | else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) | |
757 | hctx->dispatched[ilog2(queued) + 1]++; | |
758 | ||
759 | /* | |
760 | * Any items that need requeuing? Stuff them into hctx->dispatch, | |
761 | * that is where we will continue on next queue run. | |
762 | */ | |
763 | if (!list_empty(&rq_list)) { | |
764 | spin_lock(&hctx->lock); | |
765 | list_splice(&rq_list, &hctx->dispatch); | |
766 | spin_unlock(&hctx->lock); | |
767 | } | |
768 | } | |
769 | ||
506e931f JA |
770 | /* |
771 | * It'd be great if the workqueue API had a way to pass | |
772 | * in a mask and had some smarts for more clever placement. | |
773 | * For now we just round-robin here, switching for every | |
774 | * BLK_MQ_CPU_WORK_BATCH queued items. | |
775 | */ | |
776 | static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) | |
777 | { | |
778 | int cpu = hctx->next_cpu; | |
779 | ||
780 | if (--hctx->next_cpu_batch <= 0) { | |
781 | int next_cpu; | |
782 | ||
783 | next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); | |
784 | if (next_cpu >= nr_cpu_ids) | |
785 | next_cpu = cpumask_first(hctx->cpumask); | |
786 | ||
787 | hctx->next_cpu = next_cpu; | |
788 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
789 | } | |
790 | ||
791 | return cpu; | |
792 | } | |
793 | ||
320ae51f JA |
794 | void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) |
795 | { | |
5d12f905 | 796 | if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) |
320ae51f JA |
797 | return; |
798 | ||
e4043dcf | 799 | if (!async && cpumask_test_cpu(smp_processor_id(), hctx->cpumask)) |
320ae51f | 800 | __blk_mq_run_hw_queue(hctx); |
e4043dcf | 801 | else if (hctx->queue->nr_hw_queues == 1) |
70f4db63 | 802 | kblockd_schedule_delayed_work(&hctx->run_work, 0); |
e4043dcf JA |
803 | else { |
804 | unsigned int cpu; | |
805 | ||
506e931f | 806 | cpu = blk_mq_hctx_next_cpu(hctx); |
70f4db63 | 807 | kblockd_schedule_delayed_work_on(cpu, &hctx->run_work, 0); |
e4043dcf | 808 | } |
320ae51f JA |
809 | } |
810 | ||
811 | void blk_mq_run_queues(struct request_queue *q, bool async) | |
812 | { | |
813 | struct blk_mq_hw_ctx *hctx; | |
814 | int i; | |
815 | ||
816 | queue_for_each_hw_ctx(q, hctx, i) { | |
817 | if ((!blk_mq_hctx_has_pending(hctx) && | |
818 | list_empty_careful(&hctx->dispatch)) || | |
5d12f905 | 819 | test_bit(BLK_MQ_S_STOPPED, &hctx->state)) |
320ae51f JA |
820 | continue; |
821 | ||
e4043dcf | 822 | preempt_disable(); |
320ae51f | 823 | blk_mq_run_hw_queue(hctx, async); |
e4043dcf | 824 | preempt_enable(); |
320ae51f JA |
825 | } |
826 | } | |
827 | EXPORT_SYMBOL(blk_mq_run_queues); | |
828 | ||
829 | void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) | |
830 | { | |
70f4db63 CH |
831 | cancel_delayed_work(&hctx->run_work); |
832 | cancel_delayed_work(&hctx->delay_work); | |
320ae51f JA |
833 | set_bit(BLK_MQ_S_STOPPED, &hctx->state); |
834 | } | |
835 | EXPORT_SYMBOL(blk_mq_stop_hw_queue); | |
836 | ||
280d45f6 CH |
837 | void blk_mq_stop_hw_queues(struct request_queue *q) |
838 | { | |
839 | struct blk_mq_hw_ctx *hctx; | |
840 | int i; | |
841 | ||
842 | queue_for_each_hw_ctx(q, hctx, i) | |
843 | blk_mq_stop_hw_queue(hctx); | |
844 | } | |
845 | EXPORT_SYMBOL(blk_mq_stop_hw_queues); | |
846 | ||
320ae51f JA |
847 | void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) |
848 | { | |
849 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf JA |
850 | |
851 | preempt_disable(); | |
320ae51f | 852 | __blk_mq_run_hw_queue(hctx); |
e4043dcf | 853 | preempt_enable(); |
320ae51f JA |
854 | } |
855 | EXPORT_SYMBOL(blk_mq_start_hw_queue); | |
856 | ||
2f268556 CH |
857 | void blk_mq_start_hw_queues(struct request_queue *q) |
858 | { | |
859 | struct blk_mq_hw_ctx *hctx; | |
860 | int i; | |
861 | ||
862 | queue_for_each_hw_ctx(q, hctx, i) | |
863 | blk_mq_start_hw_queue(hctx); | |
864 | } | |
865 | EXPORT_SYMBOL(blk_mq_start_hw_queues); | |
866 | ||
867 | ||
1b4a3258 | 868 | void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) |
320ae51f JA |
869 | { |
870 | struct blk_mq_hw_ctx *hctx; | |
871 | int i; | |
872 | ||
873 | queue_for_each_hw_ctx(q, hctx, i) { | |
874 | if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
875 | continue; | |
876 | ||
877 | clear_bit(BLK_MQ_S_STOPPED, &hctx->state); | |
e4043dcf | 878 | preempt_disable(); |
1b4a3258 | 879 | blk_mq_run_hw_queue(hctx, async); |
e4043dcf | 880 | preempt_enable(); |
320ae51f JA |
881 | } |
882 | } | |
883 | EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); | |
884 | ||
70f4db63 | 885 | static void blk_mq_run_work_fn(struct work_struct *work) |
320ae51f JA |
886 | { |
887 | struct blk_mq_hw_ctx *hctx; | |
888 | ||
70f4db63 | 889 | hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); |
e4043dcf | 890 | |
320ae51f JA |
891 | __blk_mq_run_hw_queue(hctx); |
892 | } | |
893 | ||
70f4db63 CH |
894 | static void blk_mq_delay_work_fn(struct work_struct *work) |
895 | { | |
896 | struct blk_mq_hw_ctx *hctx; | |
897 | ||
898 | hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); | |
899 | ||
900 | if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) | |
901 | __blk_mq_run_hw_queue(hctx); | |
902 | } | |
903 | ||
904 | void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) | |
905 | { | |
906 | unsigned long tmo = msecs_to_jiffies(msecs); | |
907 | ||
908 | if (hctx->queue->nr_hw_queues == 1) | |
909 | kblockd_schedule_delayed_work(&hctx->delay_work, tmo); | |
910 | else { | |
911 | unsigned int cpu; | |
912 | ||
506e931f | 913 | cpu = blk_mq_hctx_next_cpu(hctx); |
70f4db63 CH |
914 | kblockd_schedule_delayed_work_on(cpu, &hctx->delay_work, tmo); |
915 | } | |
916 | } | |
917 | EXPORT_SYMBOL(blk_mq_delay_queue); | |
918 | ||
320ae51f | 919 | static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, |
72a0a36e | 920 | struct request *rq, bool at_head) |
320ae51f JA |
921 | { |
922 | struct blk_mq_ctx *ctx = rq->mq_ctx; | |
923 | ||
01b983c9 JA |
924 | trace_block_rq_insert(hctx->queue, rq); |
925 | ||
72a0a36e CH |
926 | if (at_head) |
927 | list_add(&rq->queuelist, &ctx->rq_list); | |
928 | else | |
929 | list_add_tail(&rq->queuelist, &ctx->rq_list); | |
4bb659b1 | 930 | |
320ae51f JA |
931 | blk_mq_hctx_mark_pending(hctx, ctx); |
932 | ||
933 | /* | |
934 | * We do this early, to ensure we are on the right CPU. | |
935 | */ | |
87ee7b11 | 936 | blk_add_timer(rq); |
320ae51f JA |
937 | } |
938 | ||
eeabc850 CH |
939 | void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, |
940 | bool async) | |
320ae51f | 941 | { |
eeabc850 | 942 | struct request_queue *q = rq->q; |
320ae51f | 943 | struct blk_mq_hw_ctx *hctx; |
eeabc850 CH |
944 | struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; |
945 | ||
946 | current_ctx = blk_mq_get_ctx(q); | |
947 | if (!cpu_online(ctx->cpu)) | |
948 | rq->mq_ctx = ctx = current_ctx; | |
320ae51f | 949 | |
320ae51f JA |
950 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
951 | ||
eeabc850 CH |
952 | if (rq->cmd_flags & (REQ_FLUSH | REQ_FUA) && |
953 | !(rq->cmd_flags & (REQ_FLUSH_SEQ))) { | |
320ae51f JA |
954 | blk_insert_flush(rq); |
955 | } else { | |
320ae51f | 956 | spin_lock(&ctx->lock); |
72a0a36e | 957 | __blk_mq_insert_request(hctx, rq, at_head); |
320ae51f | 958 | spin_unlock(&ctx->lock); |
320ae51f JA |
959 | } |
960 | ||
320ae51f JA |
961 | if (run_queue) |
962 | blk_mq_run_hw_queue(hctx, async); | |
e4043dcf JA |
963 | |
964 | blk_mq_put_ctx(current_ctx); | |
320ae51f JA |
965 | } |
966 | ||
967 | static void blk_mq_insert_requests(struct request_queue *q, | |
968 | struct blk_mq_ctx *ctx, | |
969 | struct list_head *list, | |
970 | int depth, | |
971 | bool from_schedule) | |
972 | ||
973 | { | |
974 | struct blk_mq_hw_ctx *hctx; | |
975 | struct blk_mq_ctx *current_ctx; | |
976 | ||
977 | trace_block_unplug(q, depth, !from_schedule); | |
978 | ||
979 | current_ctx = blk_mq_get_ctx(q); | |
980 | ||
981 | if (!cpu_online(ctx->cpu)) | |
982 | ctx = current_ctx; | |
983 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
984 | ||
985 | /* | |
986 | * preemption doesn't flush plug list, so it's possible ctx->cpu is | |
987 | * offline now | |
988 | */ | |
989 | spin_lock(&ctx->lock); | |
990 | while (!list_empty(list)) { | |
991 | struct request *rq; | |
992 | ||
993 | rq = list_first_entry(list, struct request, queuelist); | |
994 | list_del_init(&rq->queuelist); | |
995 | rq->mq_ctx = ctx; | |
72a0a36e | 996 | __blk_mq_insert_request(hctx, rq, false); |
320ae51f JA |
997 | } |
998 | spin_unlock(&ctx->lock); | |
999 | ||
320ae51f | 1000 | blk_mq_run_hw_queue(hctx, from_schedule); |
e4043dcf | 1001 | blk_mq_put_ctx(current_ctx); |
320ae51f JA |
1002 | } |
1003 | ||
1004 | static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) | |
1005 | { | |
1006 | struct request *rqa = container_of(a, struct request, queuelist); | |
1007 | struct request *rqb = container_of(b, struct request, queuelist); | |
1008 | ||
1009 | return !(rqa->mq_ctx < rqb->mq_ctx || | |
1010 | (rqa->mq_ctx == rqb->mq_ctx && | |
1011 | blk_rq_pos(rqa) < blk_rq_pos(rqb))); | |
1012 | } | |
1013 | ||
1014 | void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) | |
1015 | { | |
1016 | struct blk_mq_ctx *this_ctx; | |
1017 | struct request_queue *this_q; | |
1018 | struct request *rq; | |
1019 | LIST_HEAD(list); | |
1020 | LIST_HEAD(ctx_list); | |
1021 | unsigned int depth; | |
1022 | ||
1023 | list_splice_init(&plug->mq_list, &list); | |
1024 | ||
1025 | list_sort(NULL, &list, plug_ctx_cmp); | |
1026 | ||
1027 | this_q = NULL; | |
1028 | this_ctx = NULL; | |
1029 | depth = 0; | |
1030 | ||
1031 | while (!list_empty(&list)) { | |
1032 | rq = list_entry_rq(list.next); | |
1033 | list_del_init(&rq->queuelist); | |
1034 | BUG_ON(!rq->q); | |
1035 | if (rq->mq_ctx != this_ctx) { | |
1036 | if (this_ctx) { | |
1037 | blk_mq_insert_requests(this_q, this_ctx, | |
1038 | &ctx_list, depth, | |
1039 | from_schedule); | |
1040 | } | |
1041 | ||
1042 | this_ctx = rq->mq_ctx; | |
1043 | this_q = rq->q; | |
1044 | depth = 0; | |
1045 | } | |
1046 | ||
1047 | depth++; | |
1048 | list_add_tail(&rq->queuelist, &ctx_list); | |
1049 | } | |
1050 | ||
1051 | /* | |
1052 | * If 'this_ctx' is set, we know we have entries to complete | |
1053 | * on 'ctx_list'. Do those. | |
1054 | */ | |
1055 | if (this_ctx) { | |
1056 | blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, | |
1057 | from_schedule); | |
1058 | } | |
1059 | } | |
1060 | ||
1061 | static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) | |
1062 | { | |
1063 | init_request_from_bio(rq, bio); | |
1064 | blk_account_io_start(rq, 1); | |
1065 | } | |
1066 | ||
1067 | static void blk_mq_make_request(struct request_queue *q, struct bio *bio) | |
1068 | { | |
1069 | struct blk_mq_hw_ctx *hctx; | |
1070 | struct blk_mq_ctx *ctx; | |
1071 | const int is_sync = rw_is_sync(bio->bi_rw); | |
1072 | const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); | |
1073 | int rw = bio_data_dir(bio); | |
1074 | struct request *rq; | |
1075 | unsigned int use_plug, request_count = 0; | |
1076 | ||
1077 | /* | |
1078 | * If we have multiple hardware queues, just go directly to | |
1079 | * one of those for sync IO. | |
1080 | */ | |
1081 | use_plug = !is_flush_fua && ((q->nr_hw_queues == 1) || !is_sync); | |
1082 | ||
1083 | blk_queue_bounce(q, &bio); | |
1084 | ||
14ec77f3 NB |
1085 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { |
1086 | bio_endio(bio, -EIO); | |
1087 | return; | |
1088 | } | |
1089 | ||
da41a589 RE |
1090 | if (use_plug && !blk_queue_nomerges(q) && |
1091 | blk_attempt_plug_merge(q, bio, &request_count)) | |
320ae51f JA |
1092 | return; |
1093 | ||
1094 | if (blk_mq_queue_enter(q)) { | |
1095 | bio_endio(bio, -EIO); | |
1096 | return; | |
1097 | } | |
1098 | ||
1099 | ctx = blk_mq_get_ctx(q); | |
1100 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1101 | ||
27fbf4e8 SL |
1102 | if (is_sync) |
1103 | rw |= REQ_SYNC; | |
320ae51f | 1104 | trace_block_getrq(q, bio, rw); |
4bb659b1 | 1105 | rq = __blk_mq_alloc_request(hctx, ctx, GFP_ATOMIC, false); |
320ae51f | 1106 | if (likely(rq)) |
18741986 | 1107 | blk_mq_rq_ctx_init(q, ctx, rq, rw); |
320ae51f JA |
1108 | else { |
1109 | blk_mq_put_ctx(ctx); | |
1110 | trace_block_sleeprq(q, bio, rw); | |
18741986 CH |
1111 | rq = blk_mq_alloc_request_pinned(q, rw, __GFP_WAIT|GFP_ATOMIC, |
1112 | false); | |
320ae51f JA |
1113 | ctx = rq->mq_ctx; |
1114 | hctx = q->mq_ops->map_queue(q, ctx->cpu); | |
1115 | } | |
1116 | ||
1117 | hctx->queued++; | |
1118 | ||
1119 | if (unlikely(is_flush_fua)) { | |
1120 | blk_mq_bio_to_request(rq, bio); | |
320ae51f JA |
1121 | blk_insert_flush(rq); |
1122 | goto run_queue; | |
1123 | } | |
1124 | ||
1125 | /* | |
1126 | * A task plug currently exists. Since this is completely lockless, | |
1127 | * utilize that to temporarily store requests until the task is | |
1128 | * either done or scheduled away. | |
1129 | */ | |
1130 | if (use_plug) { | |
1131 | struct blk_plug *plug = current->plug; | |
1132 | ||
1133 | if (plug) { | |
1134 | blk_mq_bio_to_request(rq, bio); | |
92f399c7 | 1135 | if (list_empty(&plug->mq_list)) |
320ae51f JA |
1136 | trace_block_plug(q); |
1137 | else if (request_count >= BLK_MAX_REQUEST_COUNT) { | |
1138 | blk_flush_plug_list(plug, false); | |
1139 | trace_block_plug(q); | |
1140 | } | |
1141 | list_add_tail(&rq->queuelist, &plug->mq_list); | |
1142 | blk_mq_put_ctx(ctx); | |
1143 | return; | |
1144 | } | |
1145 | } | |
1146 | ||
c6d600c6 | 1147 | if (!(hctx->flags & BLK_MQ_F_SHOULD_MERGE)) { |
cf4b50af | 1148 | blk_mq_bio_to_request(rq, bio); |
c6d600c6 JA |
1149 | spin_lock(&ctx->lock); |
1150 | insert_rq: | |
72a0a36e | 1151 | __blk_mq_insert_request(hctx, rq, false); |
c6d600c6 | 1152 | spin_unlock(&ctx->lock); |
c6d600c6 JA |
1153 | } else { |
1154 | spin_lock(&ctx->lock); | |
1155 | if (!blk_mq_attempt_merge(q, ctx, bio)) { | |
cf4b50af | 1156 | blk_mq_bio_to_request(rq, bio); |
c6d600c6 JA |
1157 | goto insert_rq; |
1158 | } | |
1159 | ||
1160 | spin_unlock(&ctx->lock); | |
1161 | __blk_mq_free_request(hctx, ctx, rq); | |
320ae51f JA |
1162 | } |
1163 | ||
320ae51f JA |
1164 | |
1165 | /* | |
1166 | * For a SYNC request, send it to the hardware immediately. For an | |
1167 | * ASYNC request, just ensure that we run it later on. The latter | |
1168 | * allows for merging opportunities and more efficient dispatching. | |
1169 | */ | |
1170 | run_queue: | |
1171 | blk_mq_run_hw_queue(hctx, !is_sync || is_flush_fua); | |
e4043dcf | 1172 | blk_mq_put_ctx(ctx); |
320ae51f JA |
1173 | } |
1174 | ||
1175 | /* | |
1176 | * Default mapping to a software queue, since we use one per CPU. | |
1177 | */ | |
1178 | struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) | |
1179 | { | |
1180 | return q->queue_hw_ctx[q->mq_map[cpu]]; | |
1181 | } | |
1182 | EXPORT_SYMBOL(blk_mq_map_queue); | |
1183 | ||
24d2f903 | 1184 | struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_tag_set *set, |
320ae51f JA |
1185 | unsigned int hctx_index) |
1186 | { | |
4bb659b1 JA |
1187 | return kzalloc_node(sizeof(struct blk_mq_hw_ctx), GFP_KERNEL, |
1188 | set->numa_node); | |
320ae51f JA |
1189 | } |
1190 | EXPORT_SYMBOL(blk_mq_alloc_single_hw_queue); | |
1191 | ||
1192 | void blk_mq_free_single_hw_queue(struct blk_mq_hw_ctx *hctx, | |
1193 | unsigned int hctx_index) | |
1194 | { | |
1195 | kfree(hctx); | |
1196 | } | |
1197 | EXPORT_SYMBOL(blk_mq_free_single_hw_queue); | |
1198 | ||
e814e71b JA |
1199 | static int blk_mq_hctx_notify(void *data, unsigned long action, |
1200 | unsigned int cpu) | |
320ae51f JA |
1201 | { |
1202 | struct blk_mq_hw_ctx *hctx = data; | |
bccb5f7c | 1203 | struct request_queue *q = hctx->queue; |
320ae51f JA |
1204 | struct blk_mq_ctx *ctx; |
1205 | LIST_HEAD(tmp); | |
1206 | ||
1207 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) | |
e814e71b | 1208 | return NOTIFY_OK; |
320ae51f JA |
1209 | |
1210 | /* | |
1211 | * Move ctx entries to new CPU, if this one is going away. | |
1212 | */ | |
bccb5f7c | 1213 | ctx = __blk_mq_get_ctx(q, cpu); |
320ae51f JA |
1214 | |
1215 | spin_lock(&ctx->lock); | |
1216 | if (!list_empty(&ctx->rq_list)) { | |
1217 | list_splice_init(&ctx->rq_list, &tmp); | |
1429d7c9 | 1218 | blk_mq_hctx_clear_pending(hctx, ctx); |
320ae51f JA |
1219 | } |
1220 | spin_unlock(&ctx->lock); | |
1221 | ||
1222 | if (list_empty(&tmp)) | |
e814e71b | 1223 | return NOTIFY_OK; |
320ae51f | 1224 | |
bccb5f7c | 1225 | ctx = blk_mq_get_ctx(q); |
320ae51f JA |
1226 | spin_lock(&ctx->lock); |
1227 | ||
1228 | while (!list_empty(&tmp)) { | |
1229 | struct request *rq; | |
1230 | ||
1231 | rq = list_first_entry(&tmp, struct request, queuelist); | |
1232 | rq->mq_ctx = ctx; | |
1233 | list_move_tail(&rq->queuelist, &ctx->rq_list); | |
1234 | } | |
1235 | ||
bccb5f7c | 1236 | hctx = q->mq_ops->map_queue(q, ctx->cpu); |
320ae51f JA |
1237 | blk_mq_hctx_mark_pending(hctx, ctx); |
1238 | ||
1239 | spin_unlock(&ctx->lock); | |
bccb5f7c JA |
1240 | |
1241 | blk_mq_run_hw_queue(hctx, true); | |
e4043dcf | 1242 | blk_mq_put_ctx(ctx); |
e814e71b | 1243 | return NOTIFY_OK; |
320ae51f JA |
1244 | } |
1245 | ||
24d2f903 CH |
1246 | static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, |
1247 | struct blk_mq_tags *tags, unsigned int hctx_idx) | |
95363efd | 1248 | { |
e9b267d9 | 1249 | struct page *page; |
320ae51f | 1250 | |
24d2f903 | 1251 | if (tags->rqs && set->ops->exit_request) { |
e9b267d9 | 1252 | int i; |
320ae51f | 1253 | |
24d2f903 CH |
1254 | for (i = 0; i < tags->nr_tags; i++) { |
1255 | if (!tags->rqs[i]) | |
e9b267d9 | 1256 | continue; |
24d2f903 CH |
1257 | set->ops->exit_request(set->driver_data, tags->rqs[i], |
1258 | hctx_idx, i); | |
e9b267d9 | 1259 | } |
320ae51f | 1260 | } |
320ae51f | 1261 | |
24d2f903 CH |
1262 | while (!list_empty(&tags->page_list)) { |
1263 | page = list_first_entry(&tags->page_list, struct page, lru); | |
6753471c | 1264 | list_del_init(&page->lru); |
320ae51f JA |
1265 | __free_pages(page, page->private); |
1266 | } | |
1267 | ||
24d2f903 | 1268 | kfree(tags->rqs); |
320ae51f | 1269 | |
24d2f903 | 1270 | blk_mq_free_tags(tags); |
320ae51f JA |
1271 | } |
1272 | ||
1273 | static size_t order_to_size(unsigned int order) | |
1274 | { | |
4ca08500 | 1275 | return (size_t)PAGE_SIZE << order; |
320ae51f JA |
1276 | } |
1277 | ||
24d2f903 CH |
1278 | static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, |
1279 | unsigned int hctx_idx) | |
320ae51f | 1280 | { |
24d2f903 | 1281 | struct blk_mq_tags *tags; |
320ae51f JA |
1282 | unsigned int i, j, entries_per_page, max_order = 4; |
1283 | size_t rq_size, left; | |
1284 | ||
24d2f903 CH |
1285 | tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, |
1286 | set->numa_node); | |
1287 | if (!tags) | |
1288 | return NULL; | |
320ae51f | 1289 | |
24d2f903 CH |
1290 | INIT_LIST_HEAD(&tags->page_list); |
1291 | ||
1292 | tags->rqs = kmalloc_node(set->queue_depth * sizeof(struct request *), | |
1293 | GFP_KERNEL, set->numa_node); | |
1294 | if (!tags->rqs) { | |
1295 | blk_mq_free_tags(tags); | |
1296 | return NULL; | |
1297 | } | |
320ae51f JA |
1298 | |
1299 | /* | |
1300 | * rq_size is the size of the request plus driver payload, rounded | |
1301 | * to the cacheline size | |
1302 | */ | |
24d2f903 | 1303 | rq_size = round_up(sizeof(struct request) + set->cmd_size, |
320ae51f | 1304 | cache_line_size()); |
24d2f903 | 1305 | left = rq_size * set->queue_depth; |
320ae51f | 1306 | |
24d2f903 | 1307 | for (i = 0; i < set->queue_depth; ) { |
320ae51f JA |
1308 | int this_order = max_order; |
1309 | struct page *page; | |
1310 | int to_do; | |
1311 | void *p; | |
1312 | ||
1313 | while (left < order_to_size(this_order - 1) && this_order) | |
1314 | this_order--; | |
1315 | ||
1316 | do { | |
24d2f903 CH |
1317 | page = alloc_pages_node(set->numa_node, GFP_KERNEL, |
1318 | this_order); | |
320ae51f JA |
1319 | if (page) |
1320 | break; | |
1321 | if (!this_order--) | |
1322 | break; | |
1323 | if (order_to_size(this_order) < rq_size) | |
1324 | break; | |
1325 | } while (1); | |
1326 | ||
1327 | if (!page) | |
24d2f903 | 1328 | goto fail; |
320ae51f JA |
1329 | |
1330 | page->private = this_order; | |
24d2f903 | 1331 | list_add_tail(&page->lru, &tags->page_list); |
320ae51f JA |
1332 | |
1333 | p = page_address(page); | |
1334 | entries_per_page = order_to_size(this_order) / rq_size; | |
24d2f903 | 1335 | to_do = min(entries_per_page, set->queue_depth - i); |
320ae51f JA |
1336 | left -= to_do * rq_size; |
1337 | for (j = 0; j < to_do; j++) { | |
24d2f903 CH |
1338 | tags->rqs[i] = p; |
1339 | if (set->ops->init_request) { | |
1340 | if (set->ops->init_request(set->driver_data, | |
1341 | tags->rqs[i], hctx_idx, i, | |
1342 | set->numa_node)) | |
1343 | goto fail; | |
e9b267d9 CH |
1344 | } |
1345 | ||
320ae51f JA |
1346 | p += rq_size; |
1347 | i++; | |
1348 | } | |
1349 | } | |
1350 | ||
24d2f903 | 1351 | return tags; |
320ae51f | 1352 | |
24d2f903 CH |
1353 | fail: |
1354 | pr_warn("%s: failed to allocate requests\n", __func__); | |
1355 | blk_mq_free_rq_map(set, tags, hctx_idx); | |
1356 | return NULL; | |
320ae51f JA |
1357 | } |
1358 | ||
1429d7c9 JA |
1359 | static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) |
1360 | { | |
1361 | kfree(bitmap->map); | |
1362 | } | |
1363 | ||
1364 | static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) | |
1365 | { | |
1366 | unsigned int bpw = 8, total, num_maps, i; | |
1367 | ||
1368 | bitmap->bits_per_word = bpw; | |
1369 | ||
1370 | num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; | |
1371 | bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), | |
1372 | GFP_KERNEL, node); | |
1373 | if (!bitmap->map) | |
1374 | return -ENOMEM; | |
1375 | ||
1376 | bitmap->map_size = num_maps; | |
1377 | ||
1378 | total = nr_cpu_ids; | |
1379 | for (i = 0; i < num_maps; i++) { | |
1380 | bitmap->map[i].depth = min(total, bitmap->bits_per_word); | |
1381 | total -= bitmap->map[i].depth; | |
1382 | } | |
1383 | ||
1384 | return 0; | |
1385 | } | |
1386 | ||
320ae51f | 1387 | static int blk_mq_init_hw_queues(struct request_queue *q, |
24d2f903 | 1388 | struct blk_mq_tag_set *set) |
320ae51f JA |
1389 | { |
1390 | struct blk_mq_hw_ctx *hctx; | |
1391 | unsigned int i, j; | |
1392 | ||
1393 | /* | |
1394 | * Initialize hardware queues | |
1395 | */ | |
1396 | queue_for_each_hw_ctx(q, hctx, i) { | |
320ae51f JA |
1397 | int node; |
1398 | ||
1399 | node = hctx->numa_node; | |
1400 | if (node == NUMA_NO_NODE) | |
24d2f903 | 1401 | node = hctx->numa_node = set->numa_node; |
320ae51f | 1402 | |
70f4db63 CH |
1403 | INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); |
1404 | INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); | |
320ae51f JA |
1405 | spin_lock_init(&hctx->lock); |
1406 | INIT_LIST_HEAD(&hctx->dispatch); | |
1407 | hctx->queue = q; | |
1408 | hctx->queue_num = i; | |
24d2f903 CH |
1409 | hctx->flags = set->flags; |
1410 | hctx->cmd_size = set->cmd_size; | |
320ae51f JA |
1411 | |
1412 | blk_mq_init_cpu_notifier(&hctx->cpu_notifier, | |
1413 | blk_mq_hctx_notify, hctx); | |
1414 | blk_mq_register_cpu_notifier(&hctx->cpu_notifier); | |
1415 | ||
24d2f903 | 1416 | hctx->tags = set->tags[i]; |
320ae51f JA |
1417 | |
1418 | /* | |
1419 | * Allocate space for all possible cpus to avoid allocation in | |
1420 | * runtime | |
1421 | */ | |
1422 | hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), | |
1423 | GFP_KERNEL, node); | |
1424 | if (!hctx->ctxs) | |
1425 | break; | |
1426 | ||
1429d7c9 | 1427 | if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) |
320ae51f JA |
1428 | break; |
1429 | ||
320ae51f JA |
1430 | hctx->nr_ctx = 0; |
1431 | ||
24d2f903 CH |
1432 | if (set->ops->init_hctx && |
1433 | set->ops->init_hctx(hctx, set->driver_data, i)) | |
320ae51f JA |
1434 | break; |
1435 | } | |
1436 | ||
1437 | if (i == q->nr_hw_queues) | |
1438 | return 0; | |
1439 | ||
1440 | /* | |
1441 | * Init failed | |
1442 | */ | |
1443 | queue_for_each_hw_ctx(q, hctx, j) { | |
1444 | if (i == j) | |
1445 | break; | |
1446 | ||
24d2f903 CH |
1447 | if (set->ops->exit_hctx) |
1448 | set->ops->exit_hctx(hctx, j); | |
320ae51f JA |
1449 | |
1450 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); | |
320ae51f | 1451 | kfree(hctx->ctxs); |
1429d7c9 | 1452 | blk_mq_free_bitmap(&hctx->ctx_map); |
320ae51f JA |
1453 | } |
1454 | ||
1455 | return 1; | |
1456 | } | |
1457 | ||
1458 | static void blk_mq_init_cpu_queues(struct request_queue *q, | |
1459 | unsigned int nr_hw_queues) | |
1460 | { | |
1461 | unsigned int i; | |
1462 | ||
1463 | for_each_possible_cpu(i) { | |
1464 | struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); | |
1465 | struct blk_mq_hw_ctx *hctx; | |
1466 | ||
1467 | memset(__ctx, 0, sizeof(*__ctx)); | |
1468 | __ctx->cpu = i; | |
1469 | spin_lock_init(&__ctx->lock); | |
1470 | INIT_LIST_HEAD(&__ctx->rq_list); | |
1471 | __ctx->queue = q; | |
1472 | ||
1473 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
320ae51f JA |
1474 | if (!cpu_online(i)) |
1475 | continue; | |
1476 | ||
e4043dcf JA |
1477 | hctx = q->mq_ops->map_queue(q, i); |
1478 | cpumask_set_cpu(i, hctx->cpumask); | |
1479 | hctx->nr_ctx++; | |
1480 | ||
320ae51f JA |
1481 | /* |
1482 | * Set local node, IFF we have more than one hw queue. If | |
1483 | * not, we remain on the home node of the device | |
1484 | */ | |
1485 | if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) | |
1486 | hctx->numa_node = cpu_to_node(i); | |
1487 | } | |
1488 | } | |
1489 | ||
1490 | static void blk_mq_map_swqueue(struct request_queue *q) | |
1491 | { | |
1492 | unsigned int i; | |
1493 | struct blk_mq_hw_ctx *hctx; | |
1494 | struct blk_mq_ctx *ctx; | |
1495 | ||
1496 | queue_for_each_hw_ctx(q, hctx, i) { | |
e4043dcf | 1497 | cpumask_clear(hctx->cpumask); |
320ae51f JA |
1498 | hctx->nr_ctx = 0; |
1499 | } | |
1500 | ||
1501 | /* | |
1502 | * Map software to hardware queues | |
1503 | */ | |
1504 | queue_for_each_ctx(q, ctx, i) { | |
1505 | /* If the cpu isn't online, the cpu is mapped to first hctx */ | |
e4043dcf JA |
1506 | if (!cpu_online(i)) |
1507 | continue; | |
1508 | ||
320ae51f | 1509 | hctx = q->mq_ops->map_queue(q, i); |
e4043dcf | 1510 | cpumask_set_cpu(i, hctx->cpumask); |
320ae51f JA |
1511 | ctx->index_hw = hctx->nr_ctx; |
1512 | hctx->ctxs[hctx->nr_ctx++] = ctx; | |
1513 | } | |
506e931f JA |
1514 | |
1515 | queue_for_each_hw_ctx(q, hctx, i) { | |
1516 | hctx->next_cpu = cpumask_first(hctx->cpumask); | |
1517 | hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; | |
1518 | } | |
320ae51f JA |
1519 | } |
1520 | ||
0d2602ca JA |
1521 | static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |
1522 | { | |
1523 | struct blk_mq_hw_ctx *hctx; | |
1524 | struct request_queue *q; | |
1525 | bool shared; | |
1526 | int i; | |
1527 | ||
1528 | if (set->tag_list.next == set->tag_list.prev) | |
1529 | shared = false; | |
1530 | else | |
1531 | shared = true; | |
1532 | ||
1533 | list_for_each_entry(q, &set->tag_list, tag_set_list) { | |
1534 | blk_mq_freeze_queue(q); | |
1535 | ||
1536 | queue_for_each_hw_ctx(q, hctx, i) { | |
1537 | if (shared) | |
1538 | hctx->flags |= BLK_MQ_F_TAG_SHARED; | |
1539 | else | |
1540 | hctx->flags &= ~BLK_MQ_F_TAG_SHARED; | |
1541 | } | |
1542 | blk_mq_unfreeze_queue(q); | |
1543 | } | |
1544 | } | |
1545 | ||
1546 | static void blk_mq_del_queue_tag_set(struct request_queue *q) | |
1547 | { | |
1548 | struct blk_mq_tag_set *set = q->tag_set; | |
1549 | ||
1550 | blk_mq_freeze_queue(q); | |
1551 | ||
1552 | mutex_lock(&set->tag_list_lock); | |
1553 | list_del_init(&q->tag_set_list); | |
1554 | blk_mq_update_tag_set_depth(set); | |
1555 | mutex_unlock(&set->tag_list_lock); | |
1556 | ||
1557 | blk_mq_unfreeze_queue(q); | |
1558 | } | |
1559 | ||
1560 | static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, | |
1561 | struct request_queue *q) | |
1562 | { | |
1563 | q->tag_set = set; | |
1564 | ||
1565 | mutex_lock(&set->tag_list_lock); | |
1566 | list_add_tail(&q->tag_set_list, &set->tag_list); | |
1567 | blk_mq_update_tag_set_depth(set); | |
1568 | mutex_unlock(&set->tag_list_lock); | |
1569 | } | |
1570 | ||
24d2f903 | 1571 | struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) |
320ae51f JA |
1572 | { |
1573 | struct blk_mq_hw_ctx **hctxs; | |
1574 | struct blk_mq_ctx *ctx; | |
1575 | struct request_queue *q; | |
1576 | int i; | |
1577 | ||
320ae51f JA |
1578 | ctx = alloc_percpu(struct blk_mq_ctx); |
1579 | if (!ctx) | |
1580 | return ERR_PTR(-ENOMEM); | |
1581 | ||
24d2f903 CH |
1582 | hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, |
1583 | set->numa_node); | |
320ae51f JA |
1584 | |
1585 | if (!hctxs) | |
1586 | goto err_percpu; | |
1587 | ||
24d2f903 CH |
1588 | for (i = 0; i < set->nr_hw_queues; i++) { |
1589 | hctxs[i] = set->ops->alloc_hctx(set, i); | |
320ae51f JA |
1590 | if (!hctxs[i]) |
1591 | goto err_hctxs; | |
1592 | ||
e4043dcf JA |
1593 | if (!zalloc_cpumask_var(&hctxs[i]->cpumask, GFP_KERNEL)) |
1594 | goto err_hctxs; | |
1595 | ||
0d2602ca | 1596 | atomic_set(&hctxs[i]->nr_active, 0); |
320ae51f JA |
1597 | hctxs[i]->numa_node = NUMA_NO_NODE; |
1598 | hctxs[i]->queue_num = i; | |
1599 | } | |
1600 | ||
24d2f903 | 1601 | q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); |
320ae51f JA |
1602 | if (!q) |
1603 | goto err_hctxs; | |
1604 | ||
24d2f903 | 1605 | q->mq_map = blk_mq_make_queue_map(set); |
320ae51f JA |
1606 | if (!q->mq_map) |
1607 | goto err_map; | |
1608 | ||
1609 | setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); | |
1610 | blk_queue_rq_timeout(q, 30000); | |
1611 | ||
1612 | q->nr_queues = nr_cpu_ids; | |
24d2f903 | 1613 | q->nr_hw_queues = set->nr_hw_queues; |
320ae51f JA |
1614 | |
1615 | q->queue_ctx = ctx; | |
1616 | q->queue_hw_ctx = hctxs; | |
1617 | ||
24d2f903 | 1618 | q->mq_ops = set->ops; |
94eddfbe | 1619 | q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; |
320ae51f | 1620 | |
1be036e9 CH |
1621 | q->sg_reserved_size = INT_MAX; |
1622 | ||
320ae51f | 1623 | blk_queue_make_request(q, blk_mq_make_request); |
87ee7b11 | 1624 | blk_queue_rq_timed_out(q, blk_mq_rq_timed_out); |
24d2f903 CH |
1625 | if (set->timeout) |
1626 | blk_queue_rq_timeout(q, set->timeout); | |
320ae51f | 1627 | |
eba71768 JA |
1628 | /* |
1629 | * Do this after blk_queue_make_request() overrides it... | |
1630 | */ | |
1631 | q->nr_requests = set->queue_depth; | |
1632 | ||
24d2f903 CH |
1633 | if (set->ops->complete) |
1634 | blk_queue_softirq_done(q, set->ops->complete); | |
30a91cb4 | 1635 | |
320ae51f | 1636 | blk_mq_init_flush(q); |
24d2f903 | 1637 | blk_mq_init_cpu_queues(q, set->nr_hw_queues); |
320ae51f | 1638 | |
24d2f903 CH |
1639 | q->flush_rq = kzalloc(round_up(sizeof(struct request) + |
1640 | set->cmd_size, cache_line_size()), | |
1641 | GFP_KERNEL); | |
18741986 | 1642 | if (!q->flush_rq) |
320ae51f JA |
1643 | goto err_hw; |
1644 | ||
24d2f903 | 1645 | if (blk_mq_init_hw_queues(q, set)) |
18741986 CH |
1646 | goto err_flush_rq; |
1647 | ||
320ae51f JA |
1648 | blk_mq_map_swqueue(q); |
1649 | ||
1650 | mutex_lock(&all_q_mutex); | |
1651 | list_add_tail(&q->all_q_node, &all_q_list); | |
1652 | mutex_unlock(&all_q_mutex); | |
1653 | ||
0d2602ca JA |
1654 | blk_mq_add_queue_tag_set(set, q); |
1655 | ||
320ae51f | 1656 | return q; |
18741986 CH |
1657 | |
1658 | err_flush_rq: | |
1659 | kfree(q->flush_rq); | |
320ae51f JA |
1660 | err_hw: |
1661 | kfree(q->mq_map); | |
1662 | err_map: | |
1663 | blk_cleanup_queue(q); | |
1664 | err_hctxs: | |
24d2f903 | 1665 | for (i = 0; i < set->nr_hw_queues; i++) { |
320ae51f JA |
1666 | if (!hctxs[i]) |
1667 | break; | |
e4043dcf | 1668 | free_cpumask_var(hctxs[i]->cpumask); |
24d2f903 | 1669 | set->ops->free_hctx(hctxs[i], i); |
320ae51f JA |
1670 | } |
1671 | kfree(hctxs); | |
1672 | err_percpu: | |
1673 | free_percpu(ctx); | |
1674 | return ERR_PTR(-ENOMEM); | |
1675 | } | |
1676 | EXPORT_SYMBOL(blk_mq_init_queue); | |
1677 | ||
1678 | void blk_mq_free_queue(struct request_queue *q) | |
1679 | { | |
1680 | struct blk_mq_hw_ctx *hctx; | |
1681 | int i; | |
1682 | ||
0d2602ca JA |
1683 | blk_mq_del_queue_tag_set(q); |
1684 | ||
320ae51f | 1685 | queue_for_each_hw_ctx(q, hctx, i) { |
320ae51f | 1686 | kfree(hctx->ctxs); |
320ae51f JA |
1687 | blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); |
1688 | if (q->mq_ops->exit_hctx) | |
1689 | q->mq_ops->exit_hctx(hctx, i); | |
e4043dcf | 1690 | free_cpumask_var(hctx->cpumask); |
320ae51f JA |
1691 | q->mq_ops->free_hctx(hctx, i); |
1692 | } | |
1693 | ||
1694 | free_percpu(q->queue_ctx); | |
1695 | kfree(q->queue_hw_ctx); | |
1696 | kfree(q->mq_map); | |
1697 | ||
1698 | q->queue_ctx = NULL; | |
1699 | q->queue_hw_ctx = NULL; | |
1700 | q->mq_map = NULL; | |
1701 | ||
1702 | mutex_lock(&all_q_mutex); | |
1703 | list_del_init(&q->all_q_node); | |
1704 | mutex_unlock(&all_q_mutex); | |
1705 | } | |
320ae51f JA |
1706 | |
1707 | /* Basically redo blk_mq_init_queue with queue frozen */ | |
f618ef7c | 1708 | static void blk_mq_queue_reinit(struct request_queue *q) |
320ae51f JA |
1709 | { |
1710 | blk_mq_freeze_queue(q); | |
1711 | ||
1712 | blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues); | |
1713 | ||
1714 | /* | |
1715 | * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe | |
1716 | * we should change hctx numa_node according to new topology (this | |
1717 | * involves free and re-allocate memory, worthy doing?) | |
1718 | */ | |
1719 | ||
1720 | blk_mq_map_swqueue(q); | |
1721 | ||
1722 | blk_mq_unfreeze_queue(q); | |
1723 | } | |
1724 | ||
f618ef7c PG |
1725 | static int blk_mq_queue_reinit_notify(struct notifier_block *nb, |
1726 | unsigned long action, void *hcpu) | |
320ae51f JA |
1727 | { |
1728 | struct request_queue *q; | |
1729 | ||
1730 | /* | |
9fccfed8 JA |
1731 | * Before new mappings are established, hotadded cpu might already |
1732 | * start handling requests. This doesn't break anything as we map | |
1733 | * offline CPUs to first hardware queue. We will re-init the queue | |
1734 | * below to get optimal settings. | |
320ae51f JA |
1735 | */ |
1736 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN && | |
1737 | action != CPU_ONLINE && action != CPU_ONLINE_FROZEN) | |
1738 | return NOTIFY_OK; | |
1739 | ||
1740 | mutex_lock(&all_q_mutex); | |
1741 | list_for_each_entry(q, &all_q_list, all_q_node) | |
1742 | blk_mq_queue_reinit(q); | |
1743 | mutex_unlock(&all_q_mutex); | |
1744 | return NOTIFY_OK; | |
1745 | } | |
1746 | ||
24d2f903 CH |
1747 | int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) |
1748 | { | |
1749 | int i; | |
1750 | ||
1751 | if (!set->nr_hw_queues) | |
1752 | return -EINVAL; | |
1753 | if (!set->queue_depth || set->queue_depth > BLK_MQ_MAX_DEPTH) | |
1754 | return -EINVAL; | |
1755 | if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) | |
1756 | return -EINVAL; | |
1757 | ||
1758 | if (!set->nr_hw_queues || | |
1759 | !set->ops->queue_rq || !set->ops->map_queue || | |
1760 | !set->ops->alloc_hctx || !set->ops->free_hctx) | |
1761 | return -EINVAL; | |
1762 | ||
1763 | ||
48479005 ML |
1764 | set->tags = kmalloc_node(set->nr_hw_queues * |
1765 | sizeof(struct blk_mq_tags *), | |
24d2f903 CH |
1766 | GFP_KERNEL, set->numa_node); |
1767 | if (!set->tags) | |
1768 | goto out; | |
1769 | ||
1770 | for (i = 0; i < set->nr_hw_queues; i++) { | |
1771 | set->tags[i] = blk_mq_init_rq_map(set, i); | |
1772 | if (!set->tags[i]) | |
1773 | goto out_unwind; | |
1774 | } | |
1775 | ||
0d2602ca JA |
1776 | mutex_init(&set->tag_list_lock); |
1777 | INIT_LIST_HEAD(&set->tag_list); | |
1778 | ||
24d2f903 CH |
1779 | return 0; |
1780 | ||
1781 | out_unwind: | |
1782 | while (--i >= 0) | |
1783 | blk_mq_free_rq_map(set, set->tags[i], i); | |
1784 | out: | |
1785 | return -ENOMEM; | |
1786 | } | |
1787 | EXPORT_SYMBOL(blk_mq_alloc_tag_set); | |
1788 | ||
1789 | void blk_mq_free_tag_set(struct blk_mq_tag_set *set) | |
1790 | { | |
1791 | int i; | |
1792 | ||
1793 | for (i = 0; i < set->nr_hw_queues; i++) | |
1794 | blk_mq_free_rq_map(set, set->tags[i], i); | |
981bd189 | 1795 | kfree(set->tags); |
24d2f903 CH |
1796 | } |
1797 | EXPORT_SYMBOL(blk_mq_free_tag_set); | |
1798 | ||
e3a2b3f9 JA |
1799 | int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) |
1800 | { | |
1801 | struct blk_mq_tag_set *set = q->tag_set; | |
1802 | struct blk_mq_hw_ctx *hctx; | |
1803 | int i, ret; | |
1804 | ||
1805 | if (!set || nr > set->queue_depth) | |
1806 | return -EINVAL; | |
1807 | ||
1808 | ret = 0; | |
1809 | queue_for_each_hw_ctx(q, hctx, i) { | |
1810 | ret = blk_mq_tag_update_depth(hctx->tags, nr); | |
1811 | if (ret) | |
1812 | break; | |
1813 | } | |
1814 | ||
1815 | if (!ret) | |
1816 | q->nr_requests = nr; | |
1817 | ||
1818 | return ret; | |
1819 | } | |
1820 | ||
676141e4 JA |
1821 | void blk_mq_disable_hotplug(void) |
1822 | { | |
1823 | mutex_lock(&all_q_mutex); | |
1824 | } | |
1825 | ||
1826 | void blk_mq_enable_hotplug(void) | |
1827 | { | |
1828 | mutex_unlock(&all_q_mutex); | |
1829 | } | |
1830 | ||
320ae51f JA |
1831 | static int __init blk_mq_init(void) |
1832 | { | |
320ae51f JA |
1833 | blk_mq_cpu_init(); |
1834 | ||
1835 | /* Must be called after percpu_counter_hotcpu_callback() */ | |
1836 | hotcpu_notifier(blk_mq_queue_reinit_notify, -10); | |
1837 | ||
1838 | return 0; | |
1839 | } | |
1840 | subsys_initcall(blk_mq_init); |