blob: 3f8577e2c13be0440d7af403cb8498d8a4b78afa [file] [log] [blame]
Mike Snitzer4cc96132016-05-12 16:28:10 -04001/*
2 * Copyright (C) 2016 Red Hat, Inc. All rights reserved.
3 *
4 * This file is released under the GPL.
5 */
6
7#include "dm-core.h"
8#include "dm-rq.h"
9
10#include <linux/elevator.h> /* for rq_end_sector() */
11#include <linux/blk-mq.h>
12
13#define DM_MSG_PREFIX "core-rq"
14
Mike Snitzere689fba2019-02-20 15:37:44 -050015/*
16 * One of these is allocated per request.
17 */
18struct dm_rq_target_io {
19 struct mapped_device *md;
20 struct dm_target *ti;
21 struct request *orig, *clone;
22 struct kthread_work work;
23 blk_status_t error;
24 union map_info info;
25 struct dm_stats_aux stats_aux;
26 unsigned long duration_jiffies;
27 unsigned n_sectors;
28 unsigned completed;
29};
30
Mike Snitzer4cc96132016-05-12 16:28:10 -040031#define DM_MQ_NR_HW_QUEUES 1
32#define DM_MQ_QUEUE_DEPTH 2048
33static unsigned dm_mq_nr_hw_queues = DM_MQ_NR_HW_QUEUES;
34static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH;
35
36/*
37 * Request-based DM's mempools' reserved IOs set by the user.
38 */
39#define RESERVED_REQUEST_BASED_IOS 256
40static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS;
41
Mike Snitzer4cc96132016-05-12 16:28:10 -040042unsigned dm_get_reserved_rq_based_ios(void)
43{
44 return __dm_get_module_param(&reserved_rq_based_ios,
45 RESERVED_REQUEST_BASED_IOS, DM_RESERVED_MAX_IOS);
46}
47EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios);
48
49static unsigned dm_get_blk_mq_nr_hw_queues(void)
50{
51 return __dm_get_module_param(&dm_mq_nr_hw_queues, 1, 32);
52}
53
54static unsigned dm_get_blk_mq_queue_depth(void)
55{
56 return __dm_get_module_param(&dm_mq_queue_depth,
57 DM_MQ_QUEUE_DEPTH, BLK_MQ_MAX_DEPTH);
58}
59
60int dm_request_based(struct mapped_device *md)
61{
Jens Axboe344e9ff2018-11-15 12:22:51 -070062 return queue_is_mq(md->queue);
Mike Snitzer4cc96132016-05-12 16:28:10 -040063}
64
Jens Axboe6a23e052018-10-10 20:49:26 -060065void dm_start_queue(struct request_queue *q)
Mike Snitzer9dbeaea2016-09-01 11:59:33 -040066{
Ming Leif6601742017-06-06 23:22:04 +080067 blk_mq_unquiesce_queue(q);
Mike Snitzer9dbeaea2016-09-01 11:59:33 -040068 blk_mq_kick_requeue_list(q);
69}
70
Jens Axboe6a23e052018-10-10 20:49:26 -060071void dm_stop_queue(struct request_queue *q)
Bart Van Assche2397a152016-08-31 15:18:11 -070072{
Bart Van Asschef0d33ab2016-10-28 17:22:00 -070073 if (blk_mq_queue_stopped(q))
Mike Snitzer4cc96132016-05-12 16:28:10 -040074 return;
Mike Snitzer4cc96132016-05-12 16:28:10 -040075
Bart Van Assche7b17c2f2016-10-28 17:22:16 -070076 blk_mq_quiesce_queue(q);
Mike Snitzer4cc96132016-05-12 16:28:10 -040077}
78
Mike Snitzer4cc96132016-05-12 16:28:10 -040079/*
80 * Partial completion handling for request-based dm
81 */
82static void end_clone_bio(struct bio *clone)
83{
84 struct dm_rq_clone_bio_info *info =
85 container_of(clone, struct dm_rq_clone_bio_info, clone);
86 struct dm_rq_target_io *tio = info->tio;
Mike Snitzer4cc96132016-05-12 16:28:10 -040087 unsigned int nr_bytes = info->orig->bi_iter.bi_size;
Christoph Hellwig4e4cbee2017-06-03 09:38:06 +020088 blk_status_t error = clone->bi_status;
Ming Leidc6364b2017-08-24 20:19:52 +080089 bool is_last = !clone->bi_next;
Mike Snitzer4cc96132016-05-12 16:28:10 -040090
91 bio_put(clone);
92
93 if (tio->error)
94 /*
95 * An error has already been detected on the request.
96 * Once error occurred, just let clone->end_io() handle
97 * the remainder.
98 */
99 return;
100 else if (error) {
101 /*
102 * Don't notice the error to the upper layer yet.
103 * The error handling decision is made by the target driver,
104 * when the request is completed.
105 */
106 tio->error = error;
Ming Leidc6364b2017-08-24 20:19:52 +0800107 goto exit;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400108 }
109
110 /*
111 * I/O for the bio successfully completed.
112 * Notice the data completion to the upper layer.
113 */
Ming Leidc6364b2017-08-24 20:19:52 +0800114 tio->completed += nr_bytes;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400115
116 /*
117 * Update the original request.
Pavel Begunkovd370ad22019-06-20 20:50:50 +0300118 * Do not use blk_mq_end_request() here, because it may complete
Mike Snitzer4cc96132016-05-12 16:28:10 -0400119 * the original request before the clone, and break the ordering.
120 */
Ming Leidc6364b2017-08-24 20:19:52 +0800121 if (is_last)
122 exit:
123 blk_update_request(tio->orig, BLK_STS_OK, tio->completed);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400124}
125
126static struct dm_rq_target_io *tio_from_request(struct request *rq)
127{
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100128 return blk_mq_rq_to_pdu(rq);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400129}
130
131static void rq_end_stats(struct mapped_device *md, struct request *orig)
132{
133 if (unlikely(dm_stats_used(&md->stats))) {
134 struct dm_rq_target_io *tio = tio_from_request(orig);
135 tio->duration_jiffies = jiffies - tio->duration_jiffies;
136 dm_stats_account_io(&md->stats, rq_data_dir(orig),
137 blk_rq_pos(orig), tio->n_sectors, true,
138 tio->duration_jiffies, &tio->stats_aux);
139 }
140}
141
142/*
143 * Don't touch any member of the md after calling this function because
144 * the md may be freed in dm_put() at the end of this function.
145 * Or do dm_get() before calling this function and dm_put() later.
146 */
Mike Snitzer2adc5c52018-11-08 14:59:41 -0500147static void rq_completed(struct mapped_device *md)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400148{
Mike Snitzer4cc96132016-05-12 16:28:10 -0400149 /* nudge anyone waiting on suspend queue */
Mikulas Patocka645efa82019-02-05 05:09:00 -0500150 if (unlikely(wq_has_sleeper(&md->wait)))
Mike Snitzerc4576ae2018-12-11 09:10:26 -0500151 wake_up(&md->wait);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400152
153 /*
Mike Snitzer4cc96132016-05-12 16:28:10 -0400154 * dm_put() must be at the end of this function. See the comment above
155 */
156 dm_put(md);
157}
158
Mike Snitzer4cc96132016-05-12 16:28:10 -0400159/*
160 * Complete the clone and the original request.
161 * Must be called without clone's queue lock held,
162 * see end_clone_request() for more details.
163 */
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200164static void dm_end_request(struct request *clone, blk_status_t error)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400165{
Mike Snitzer4cc96132016-05-12 16:28:10 -0400166 struct dm_rq_target_io *tio = clone->end_io_data;
167 struct mapped_device *md = tio->md;
168 struct request *rq = tio->orig;
169
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100170 blk_rq_unprep_clone(clone);
Yufen Yu5de719e2019-04-24 23:19:05 +0800171 tio->ti->type->release_clone_rq(clone, NULL);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400172
Mike Snitzer4cc96132016-05-12 16:28:10 -0400173 rq_end_stats(md, rq);
Jens Axboe6a23e052018-10-10 20:49:26 -0600174 blk_mq_end_request(rq, error);
Mike Snitzer2adc5c52018-11-08 14:59:41 -0500175 rq_completed(md);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400176}
177
Mike Snitzere0c10752016-09-14 10:36:39 -0400178static void __dm_mq_kick_requeue_list(struct request_queue *q, unsigned long msecs)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400179{
Bart Van Assche52d7f1b2016-10-28 17:20:32 -0700180 blk_mq_delay_kick_requeue_list(q, msecs);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400181}
182
Mike Snitzere0c10752016-09-14 10:36:39 -0400183void dm_mq_kick_requeue_list(struct mapped_device *md)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400184{
Mike Snitzere0c10752016-09-14 10:36:39 -0400185 __dm_mq_kick_requeue_list(dm_get_md_queue(md), 0);
186}
187EXPORT_SYMBOL(dm_mq_kick_requeue_list);
188
189static void dm_mq_delay_requeue_request(struct request *rq, unsigned long msecs)
190{
Bart Van Assche2b053ac2016-10-28 17:21:41 -0700191 blk_mq_requeue_request(rq, false);
Mike Snitzere0c10752016-09-14 10:36:39 -0400192 __dm_mq_kick_requeue_list(rq->q, msecs);
193}
194
Mike Snitzerfbc39b42016-09-13 12:16:14 -0400195static void dm_requeue_original_request(struct dm_rq_target_io *tio, bool delay_requeue)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400196{
Mike Snitzerfbc39b42016-09-13 12:16:14 -0400197 struct mapped_device *md = tio->md;
198 struct request *rq = tio->orig;
Bart Van Assched5c27f3f2017-08-09 11:32:16 -0700199 unsigned long delay_ms = delay_requeue ? 100 : 0;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400200
201 rq_end_stats(md, rq);
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100202 if (tio->clone) {
203 blk_rq_unprep_clone(tio->clone);
Yufen Yu5de719e2019-04-24 23:19:05 +0800204 tio->ti->type->release_clone_rq(tio->clone, NULL);
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100205 }
Mike Snitzer4cc96132016-05-12 16:28:10 -0400206
Jens Axboe6a23e052018-10-10 20:49:26 -0600207 dm_mq_delay_requeue_request(rq, delay_ms);
Mike Snitzer2adc5c52018-11-08 14:59:41 -0500208 rq_completed(md);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400209}
210
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200211static void dm_done(struct request *clone, blk_status_t error, bool mapped)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400212{
Christoph Hellwig7ed85782017-04-26 09:40:37 +0200213 int r = DM_ENDIO_DONE;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400214 struct dm_rq_target_io *tio = clone->end_io_data;
215 dm_request_endio_fn rq_end_io = NULL;
216
217 if (tio->ti) {
218 rq_end_io = tio->ti->type->rq_end_io;
219
220 if (mapped && rq_end_io)
221 r = rq_end_io(tio->ti, clone, error, &tio->info);
222 }
223
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200224 if (unlikely(error == BLK_STS_TARGET)) {
Mike Snitzerbcb44432019-04-03 12:23:11 -0400225 if (req_op(clone) == REQ_OP_DISCARD &&
226 !clone->q->limits.max_discard_sectors)
227 disable_discard(tio->md);
228 else if (req_op(clone) == REQ_OP_WRITE_SAME &&
229 !clone->q->limits.max_write_same_sectors)
Christoph Hellwigac62d622017-04-05 19:21:05 +0200230 disable_write_same(tio->md);
Mike Snitzerbcb44432019-04-03 12:23:11 -0400231 else if (req_op(clone) == REQ_OP_WRITE_ZEROES &&
232 !clone->q->limits.max_write_zeroes_sectors)
Christoph Hellwigac62d622017-04-05 19:21:05 +0200233 disable_write_zeroes(tio->md);
234 }
Mike Snitzer4cc96132016-05-12 16:28:10 -0400235
Christoph Hellwig7ed85782017-04-26 09:40:37 +0200236 switch (r) {
237 case DM_ENDIO_DONE:
Mike Snitzer4cc96132016-05-12 16:28:10 -0400238 /* The target wants to complete the I/O */
Christoph Hellwig7ed85782017-04-26 09:40:37 +0200239 dm_end_request(clone, error);
240 break;
241 case DM_ENDIO_INCOMPLETE:
Mike Snitzer4cc96132016-05-12 16:28:10 -0400242 /* The target will handle the I/O */
243 return;
Christoph Hellwig7ed85782017-04-26 09:40:37 +0200244 case DM_ENDIO_REQUEUE:
Mike Snitzer4cc96132016-05-12 16:28:10 -0400245 /* The target wants to requeue the I/O */
Mike Snitzerfbc39b42016-09-13 12:16:14 -0400246 dm_requeue_original_request(tio, false);
Christoph Hellwig7ed85782017-04-26 09:40:37 +0200247 break;
Mike Snitzerac514ff2018-01-12 19:53:40 -0500248 case DM_ENDIO_DELAY_REQUEUE:
249 /* The target wants to requeue the I/O after a delay */
250 dm_requeue_original_request(tio, true);
251 break;
Christoph Hellwig7ed85782017-04-26 09:40:37 +0200252 default:
Mike Snitzer4cc96132016-05-12 16:28:10 -0400253 DMWARN("unimplemented target endio return value: %d", r);
254 BUG();
255 }
256}
257
258/*
259 * Request completion handler for request-based dm
260 */
261static void dm_softirq_done(struct request *rq)
262{
263 bool mapped = true;
264 struct dm_rq_target_io *tio = tio_from_request(rq);
265 struct request *clone = tio->clone;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400266
267 if (!clone) {
Jens Axboe61febef2017-02-24 13:19:32 -0700268 struct mapped_device *md = tio->md;
269
270 rq_end_stats(md, rq);
Jens Axboe6a23e052018-10-10 20:49:26 -0600271 blk_mq_end_request(rq, tio->error);
Mike Snitzer2adc5c52018-11-08 14:59:41 -0500272 rq_completed(md);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400273 return;
274 }
275
Christoph Hellwige8064022016-10-20 15:12:13 +0200276 if (rq->rq_flags & RQF_FAILED)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400277 mapped = false;
278
279 dm_done(clone, tio->error, mapped);
280}
281
282/*
283 * Complete the clone and the original request with the error status
284 * through softirq context.
285 */
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200286static void dm_complete_request(struct request *rq, blk_status_t error)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400287{
288 struct dm_rq_target_io *tio = tio_from_request(rq);
289
290 tio->error = error;
Jens Axboe6a23e052018-10-10 20:49:26 -0600291 blk_mq_complete_request(rq);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400292}
293
294/*
295 * Complete the not-mapped clone and the original request with the error status
296 * through softirq context.
297 * Target's rq_end_io() function isn't called.
Jens Axboe6a23e052018-10-10 20:49:26 -0600298 * This may be used when the target's clone_and_map_rq() function fails.
Mike Snitzer4cc96132016-05-12 16:28:10 -0400299 */
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200300static void dm_kill_unmapped_request(struct request *rq, blk_status_t error)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400301{
Christoph Hellwige8064022016-10-20 15:12:13 +0200302 rq->rq_flags |= RQF_FAILED;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400303 dm_complete_request(rq, error);
304}
305
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200306static void end_clone_request(struct request *clone, blk_status_t error)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400307{
308 struct dm_rq_target_io *tio = clone->end_io_data;
309
Mike Snitzer4cc96132016-05-12 16:28:10 -0400310 dm_complete_request(tio->orig, error);
311}
312
Ming Lei396eaf22018-01-17 11:25:57 -0500313static blk_status_t dm_dispatch_clone_request(struct request *clone, struct request *rq)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400314{
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200315 blk_status_t r;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400316
317 if (blk_queue_io_stat(clone->q))
Christoph Hellwige8064022016-10-20 15:12:13 +0200318 clone->rq_flags |= RQF_IO_STAT;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400319
Omar Sandoval522a7772018-05-09 02:08:53 -0700320 clone->start_time_ns = ktime_get_ns();
Mike Snitzer4cc96132016-05-12 16:28:10 -0400321 r = blk_insert_cloned_request(clone->q, clone);
Ming Lei86ff7c22018-01-30 22:04:57 -0500322 if (r != BLK_STS_OK && r != BLK_STS_RESOURCE && r != BLK_STS_DEV_RESOURCE)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400323 /* must complete clone in terms of original request */
324 dm_complete_request(rq, r);
Ming Lei396eaf22018-01-17 11:25:57 -0500325 return r;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400326}
327
328static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
329 void *data)
330{
331 struct dm_rq_target_io *tio = data;
332 struct dm_rq_clone_bio_info *info =
333 container_of(bio, struct dm_rq_clone_bio_info, clone);
334
335 info->orig = bio_orig;
336 info->tio = tio;
337 bio->bi_end_io = end_clone_bio;
338
339 return 0;
340}
341
342static int setup_clone(struct request *clone, struct request *rq,
343 struct dm_rq_target_io *tio, gfp_t gfp_mask)
344{
345 int r;
346
Kent Overstreet6f1c8192018-05-20 18:25:53 -0400347 r = blk_rq_prep_clone(clone, rq, &tio->md->bs, gfp_mask,
Mike Snitzer4cc96132016-05-12 16:28:10 -0400348 dm_rq_bio_constructor, tio);
349 if (r)
350 return r;
351
Mike Snitzer4cc96132016-05-12 16:28:10 -0400352 clone->end_io = end_clone_request;
353 clone->end_io_data = tio;
354
355 tio->clone = clone;
356
357 return 0;
358}
359
Mike Snitzer4cc96132016-05-12 16:28:10 -0400360static void init_tio(struct dm_rq_target_io *tio, struct request *rq,
361 struct mapped_device *md)
362{
363 tio->md = md;
364 tio->ti = NULL;
365 tio->clone = NULL;
366 tio->orig = rq;
367 tio->error = 0;
Ming Leidc6364b2017-08-24 20:19:52 +0800368 tio->completed = 0;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400369 /*
370 * Avoid initializing info for blk-mq; it passes
371 * target-specific data through info.ptr
372 * (see: dm_mq_init_request)
373 */
374 if (!md->init_tio_pdu)
375 memset(&tio->info, 0, sizeof(tio->info));
Mike Snitzer4cc96132016-05-12 16:28:10 -0400376}
377
Mike Snitzer4cc96132016-05-12 16:28:10 -0400378/*
379 * Returns:
Mike Snitzera8ac51e2016-09-09 19:24:57 -0400380 * DM_MAPIO_* : the request has been processed as indicated
381 * DM_MAPIO_REQUEUE : the original request needs to be immediately requeued
Mike Snitzer4cc96132016-05-12 16:28:10 -0400382 * < 0 : the request was completed due to failure
383 */
Mike Snitzerfbc39b42016-09-13 12:16:14 -0400384static int map_request(struct dm_rq_target_io *tio)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400385{
386 int r;
387 struct dm_target *ti = tio->ti;
Mike Snitzerfbc39b42016-09-13 12:16:14 -0400388 struct mapped_device *md = tio->md;
389 struct request *rq = tio->orig;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400390 struct request *clone = NULL;
Ming Lei396eaf22018-01-17 11:25:57 -0500391 blk_status_t ret;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400392
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100393 r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400394 switch (r) {
395 case DM_MAPIO_SUBMITTED:
396 /* The target has taken the I/O to submit by itself later */
397 break;
398 case DM_MAPIO_REMAPPED:
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100399 if (setup_clone(clone, rq, tio, GFP_ATOMIC)) {
400 /* -ENOMEM */
Yufen Yu5de719e2019-04-24 23:19:05 +0800401 ti->type->release_clone_rq(clone, &tio->info);
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100402 return DM_MAPIO_REQUEUE;
403 }
404
Mike Snitzer4cc96132016-05-12 16:28:10 -0400405 /* The target has remapped the I/O so dispatch it */
406 trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)),
407 blk_rq_pos(rq));
Ming Lei396eaf22018-01-17 11:25:57 -0500408 ret = dm_dispatch_clone_request(clone, rq);
Ming Lei86ff7c22018-01-30 22:04:57 -0500409 if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) {
Ming Lei396eaf22018-01-17 11:25:57 -0500410 blk_rq_unprep_clone(clone);
Ming Lei226b4fc2019-07-25 10:04:59 +0800411 blk_mq_cleanup_rq(clone);
Yufen Yu5de719e2019-04-24 23:19:05 +0800412 tio->ti->type->release_clone_rq(clone, &tio->info);
Ming Lei396eaf22018-01-17 11:25:57 -0500413 tio->clone = NULL;
Mike Snitzer34743bf2018-12-10 11:55:56 -0500414 return DM_MAPIO_REQUEUE;
Ming Lei396eaf22018-01-17 11:25:57 -0500415 }
Mike Snitzer4cc96132016-05-12 16:28:10 -0400416 break;
417 case DM_MAPIO_REQUEUE:
418 /* The target wants to requeue the I/O */
Mike Snitzera8ac51e2016-09-09 19:24:57 -0400419 break;
420 case DM_MAPIO_DELAY_REQUEUE:
421 /* The target wants to requeue the I/O after a delay */
Mike Snitzerfbc39b42016-09-13 12:16:14 -0400422 dm_requeue_original_request(tio, true);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400423 break;
Christoph Hellwig412445a2017-04-26 09:40:39 +0200424 case DM_MAPIO_KILL:
Mike Snitzer4cc96132016-05-12 16:28:10 -0400425 /* The target wants to complete the I/O */
Christoph Hellwig2a842ac2017-06-03 09:38:04 +0200426 dm_kill_unmapped_request(rq, BLK_STS_IOERR);
Christoph Hellwigece07282017-05-15 17:28:36 +0200427 break;
Christoph Hellwig412445a2017-04-26 09:40:39 +0200428 default:
429 DMWARN("unimplemented target map return value: %d", r);
430 BUG();
Mike Snitzer4cc96132016-05-12 16:28:10 -0400431 }
432
Mike Snitzera8ac51e2016-09-09 19:24:57 -0400433 return r;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400434}
435
Jens Axboe6a23e052018-10-10 20:49:26 -0600436/* DEPRECATED: previously used for request-based merge heuristic in dm_request_fn() */
437ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf)
438{
439 return sprintf(buf, "%u\n", 0);
440}
441
442ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
443 const char *buf, size_t count)
444{
445 return count;
446}
447
Mike Snitzer4cc96132016-05-12 16:28:10 -0400448static void dm_start_request(struct mapped_device *md, struct request *orig)
449{
Jens Axboe6a23e052018-10-10 20:49:26 -0600450 blk_mq_start_request(orig);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400451
Mike Snitzer4cc96132016-05-12 16:28:10 -0400452 if (unlikely(dm_stats_used(&md->stats))) {
453 struct dm_rq_target_io *tio = tio_from_request(orig);
454 tio->duration_jiffies = jiffies;
455 tio->n_sectors = blk_rq_sectors(orig);
456 dm_stats_account_io(&md->stats, rq_data_dir(orig),
457 blk_rq_pos(orig), tio->n_sectors, false, 0,
458 &tio->stats_aux);
459 }
460
461 /*
462 * Hold the md reference here for the in-flight I/O.
463 * We can't rely on the reference count by device opener,
464 * because the device may be closed during the request completion
465 * when all bios are completed.
466 * See the comment in rq_completed() too.
467 */
468 dm_get(md);
469}
470
Jens Axboe6a23e052018-10-10 20:49:26 -0600471static int dm_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
472 unsigned int hctx_idx, unsigned int numa_node)
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100473{
Jens Axboe6a23e052018-10-10 20:49:26 -0600474 struct mapped_device *md = set->driver_data;
Christoph Hellwigeb8db832017-01-22 18:32:46 +0100475 struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
476
477 /*
478 * Must initialize md member of tio, otherwise it won't
479 * be available in dm_mq_queue_rq.
480 */
481 tio->md = md;
482
483 if (md->init_tio_pdu) {
484 /* target-specific per-io data is immediately after the tio */
485 tio->info.ptr = tio + 1;
486 }
487
488 return 0;
489}
490
Christoph Hellwigfc17b652017-06-03 09:38:05 +0200491static blk_status_t dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
Mike Snitzer4cc96132016-05-12 16:28:10 -0400492 const struct blk_mq_queue_data *bd)
493{
494 struct request *rq = bd->rq;
495 struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
496 struct mapped_device *md = tio->md;
497 struct dm_target *ti = md->immutable_target;
498
499 if (unlikely(!ti)) {
500 int srcu_idx;
501 struct dm_table *map = dm_get_live_table(md, &srcu_idx);
502
503 ti = dm_table_find_target(map, 0);
504 dm_put_live_table(md, srcu_idx);
505 }
506
507 if (ti->type->busy && ti->type->busy(ti))
Christoph Hellwigfc17b652017-06-03 09:38:05 +0200508 return BLK_STS_RESOURCE;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400509
510 dm_start_request(md, rq);
511
512 /* Init tio using md established in .init_request */
513 init_tio(tio, rq, md);
514
515 /*
516 * Establish tio->ti before calling map_request().
517 */
518 tio->ti = ti;
519
520 /* Direct call is fine since .queue_rq allows allocations */
Mike Snitzerfbc39b42016-09-13 12:16:14 -0400521 if (map_request(tio) == DM_MAPIO_REQUEUE) {
Mike Snitzer4cc96132016-05-12 16:28:10 -0400522 /* Undo dm_start_request() before requeuing */
523 rq_end_stats(md, rq);
Mike Snitzer2adc5c52018-11-08 14:59:41 -0500524 rq_completed(md);
Christoph Hellwigfc17b652017-06-03 09:38:05 +0200525 return BLK_STS_RESOURCE;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400526 }
527
Christoph Hellwigfc17b652017-06-03 09:38:05 +0200528 return BLK_STS_OK;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400529}
530
Eric Biggersf363b082017-03-30 13:39:16 -0700531static const struct blk_mq_ops dm_mq_ops = {
Mike Snitzer4cc96132016-05-12 16:28:10 -0400532 .queue_rq = dm_mq_queue_rq,
Mike Snitzer4cc96132016-05-12 16:28:10 -0400533 .complete = dm_softirq_done,
534 .init_request = dm_mq_init_request,
535};
536
Mike Snitzere83068a2016-05-24 21:16:51 -0400537int dm_mq_init_request_queue(struct mapped_device *md, struct dm_table *t)
Mike Snitzer4cc96132016-05-12 16:28:10 -0400538{
539 struct request_queue *q;
Mike Snitzere83068a2016-05-24 21:16:51 -0400540 struct dm_target *immutable_tgt;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400541 int err;
542
Mike Snitzer4cc96132016-05-12 16:28:10 -0400543 md->tag_set = kzalloc_node(sizeof(struct blk_mq_tag_set), GFP_KERNEL, md->numa_node_id);
544 if (!md->tag_set)
545 return -ENOMEM;
546
547 md->tag_set->ops = &dm_mq_ops;
548 md->tag_set->queue_depth = dm_get_blk_mq_queue_depth();
549 md->tag_set->numa_node = md->numa_node_id;
Ming Lei56d18f62019-02-15 19:13:24 +0800550 md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400551 md->tag_set->nr_hw_queues = dm_get_blk_mq_nr_hw_queues();
552 md->tag_set->driver_data = md;
553
554 md->tag_set->cmd_size = sizeof(struct dm_rq_target_io);
Mike Snitzere83068a2016-05-24 21:16:51 -0400555 immutable_tgt = dm_table_get_immutable_target(t);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400556 if (immutable_tgt && immutable_tgt->per_io_data_size) {
557 /* any target-specific per-io data is immediately after the tio */
558 md->tag_set->cmd_size += immutable_tgt->per_io_data_size;
559 md->init_tio_pdu = true;
560 }
561
562 err = blk_mq_alloc_tag_set(md->tag_set);
563 if (err)
564 goto out_kfree_tag_set;
565
Damien Le Moal737eb782019-09-05 18:51:33 +0900566 q = blk_mq_init_allocated_queue(md->tag_set, md->queue, true);
Mike Snitzer4cc96132016-05-12 16:28:10 -0400567 if (IS_ERR(q)) {
568 err = PTR_ERR(q);
569 goto out_tag_set;
570 }
Mike Snitzer4cc96132016-05-12 16:28:10 -0400571
Mike Snitzer4cc96132016-05-12 16:28:10 -0400572 return 0;
573
Mike Snitzer4cc96132016-05-12 16:28:10 -0400574out_tag_set:
575 blk_mq_free_tag_set(md->tag_set);
576out_kfree_tag_set:
577 kfree(md->tag_set);
578
579 return err;
580}
581
582void dm_mq_cleanup_mapped_device(struct mapped_device *md)
583{
584 if (md->tag_set) {
585 blk_mq_free_tag_set(md->tag_set);
586 kfree(md->tag_set);
587 }
588}
589
590module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR);
591MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools");
592
Jens Axboe6a23e052018-10-10 20:49:26 -0600593/* Unused, but preserved for userspace compatibility */
594static bool use_blk_mq = true;
Mike Snitzer4cc96132016-05-12 16:28:10 -0400595module_param(use_blk_mq, bool, S_IRUGO | S_IWUSR);
596MODULE_PARM_DESC(use_blk_mq, "Use block multiqueue for request-based DM devices");
597
598module_param(dm_mq_nr_hw_queues, uint, S_IRUGO | S_IWUSR);
599MODULE_PARM_DESC(dm_mq_nr_hw_queues, "Number of hardware queues for request-based dm-mq devices");
600
601module_param(dm_mq_queue_depth, uint, S_IRUGO | S_IWUSR);
602MODULE_PARM_DESC(dm_mq_queue_depth, "Queue depth for request-based dm-mq devices");