1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2003 Russell King, All Rights Reserved.
4 * Copyright 2006-2007 Pierre Ossman
5 */
6#include <linux/slab.h>
7#include <linux/module.h>
8#include <linux/blkdev.h>
9#include <linux/freezer.h>
10#include <linux/scatterlist.h>
11#include <linux/dma-mapping.h>
12#include <linux/backing-dev.h>
13
14#include <linux/mmc/card.h>
15#include <linux/mmc/host.h>
16
17#include "queue.h"
18#include "block.h"
19#include "core.h"
20#include "card.h"
21#include "crypto.h"
22#include "host.h"
23
24#define MMC_DMA_MAP_MERGE_SEGMENTS 512
25
26static inline bool mmc_cqe_dcmd_busy(struct mmc_queue *mq)
27{
28 /* Allow only 1 DCMD at a time */
29 return mq->in_flight[MMC_ISSUE_DCMD];
30}
31
32void mmc_cqe_check_busy(struct mmc_queue *mq)
33{
34 if ((mq->cqe_busy & MMC_CQE_DCMD_BUSY) && !mmc_cqe_dcmd_busy(mq))
35 mq->cqe_busy &= ~MMC_CQE_DCMD_BUSY;
36}
37
38static inline bool mmc_cqe_can_dcmd(struct mmc_host *host)
39{
40 return host->caps2 & MMC_CAP2_CQE_DCMD;
41}
42
43static enum mmc_issue_type mmc_cqe_issue_type(struct mmc_host *host,
44 struct request *req)
45{
46 switch (req_op(req)) {
47 case REQ_OP_DRV_IN:
48 case REQ_OP_DRV_OUT:
49 case REQ_OP_DISCARD:
50 case REQ_OP_SECURE_ERASE:
51 case REQ_OP_WRITE_ZEROES:
52 return MMC_ISSUE_SYNC;
53 case REQ_OP_FLUSH:
54 return mmc_cqe_can_dcmd(host) ? MMC_ISSUE_DCMD : MMC_ISSUE_SYNC;
55 default:
56 return MMC_ISSUE_ASYNC;
57 }
58}
59
60enum mmc_issue_type mmc_issue_type(struct mmc_queue *mq, struct request *req)
61{
62 struct mmc_host *host = mq->card->host;
63
64 if (host->cqe_enabled && !host->hsq_enabled)
65 return mmc_cqe_issue_type(host, req);
66
67 if (req_op(req) == REQ_OP_READ || req_op(req) == REQ_OP_WRITE)
68 return MMC_ISSUE_ASYNC;
69
70 return MMC_ISSUE_SYNC;
71}
72
73static void __mmc_cqe_recovery_notifier(struct mmc_queue *mq)
74{
75 if (!mq->recovery_needed) {
76 mq->recovery_needed = true;
77 schedule_work(work: &mq->recovery_work);
78 }
79}
80
81void mmc_cqe_recovery_notifier(struct mmc_request *mrq)
82{
83 struct mmc_queue_req *mqrq = container_of(mrq, struct mmc_queue_req,
84 brq.mrq);
85 struct request *req = mmc_queue_req_to_req(mqr: mqrq);
86 struct request_queue *q = req->q;
87 struct mmc_queue *mq = q->queuedata;
88 unsigned long flags;
89
90 spin_lock_irqsave(&mq->lock, flags);
91 __mmc_cqe_recovery_notifier(mq);
92 spin_unlock_irqrestore(lock: &mq->lock, flags);
93}
94
95static enum blk_eh_timer_return mmc_cqe_timed_out(struct request *req)
96{
97 struct mmc_queue_req *mqrq = req_to_mmc_queue_req(rq: req);
98 struct mmc_request *mrq = &mqrq->brq.mrq;
99 struct mmc_queue *mq = req->q->queuedata;
100 struct mmc_host *host = mq->card->host;
101 enum mmc_issue_type issue_type = mmc_issue_type(mq, req);
102 bool recovery_needed = false;
103
104 switch (issue_type) {
105 case MMC_ISSUE_ASYNC:
106 case MMC_ISSUE_DCMD:
107 if (host->cqe_ops->cqe_timeout(host, mrq, &recovery_needed)) {
108 if (recovery_needed)
109 mmc_cqe_recovery_notifier(mrq);
110 return BLK_EH_RESET_TIMER;
111 }
112 /* The request has gone already */
113 return BLK_EH_DONE;
114 default:
115 /* Timeout is handled by mmc core */
116 return BLK_EH_RESET_TIMER;
117 }
118}
119
120static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req)
121{
122 struct request_queue *q = req->q;
123 struct mmc_queue *mq = q->queuedata;
124 struct mmc_card *card = mq->card;
125 struct mmc_host *host = card->host;
126 unsigned long flags;
127 bool ignore_tout;
128
129 spin_lock_irqsave(&mq->lock, flags);
130 ignore_tout = mq->recovery_needed || !host->cqe_enabled || host->hsq_enabled;
131 spin_unlock_irqrestore(lock: &mq->lock, flags);
132
133 return ignore_tout ? BLK_EH_RESET_TIMER : mmc_cqe_timed_out(req);
134}
135
136static void mmc_mq_recovery_handler(struct work_struct *work)
137{
138 struct mmc_queue *mq = container_of(work, struct mmc_queue,
139 recovery_work);
140 struct request_queue *q = mq->queue;
141 struct mmc_host *host = mq->card->host;
142
143 mmc_get_card(card: mq->card, ctx: &mq->ctx);
144
145 mq->in_recovery = true;
146
147 if (host->cqe_enabled && !host->hsq_enabled)
148 mmc_blk_cqe_recovery(mq);
149 else
150 mmc_blk_mq_recovery(mq);
151
152 mq->in_recovery = false;
153
154 spin_lock_irq(lock: &mq->lock);
155 mq->recovery_needed = false;
156 spin_unlock_irq(lock: &mq->lock);
157
158 if (host->hsq_enabled)
159 host->cqe_ops->cqe_recovery_finish(host);
160
161 mmc_put_card(card: mq->card, ctx: &mq->ctx);
162
163 blk_mq_run_hw_queues(q, async: true);
164}
165
166static struct scatterlist *mmc_alloc_sg(unsigned short sg_len, gfp_t gfp)
167{
168 struct scatterlist *sg;
169
170 sg = kmalloc_array(sg_len, sizeof(*sg), gfp);
171 if (sg)
172 sg_init_table(sg, sg_len);
173
174 return sg;
175}
176
177static void mmc_queue_setup_discard(struct mmc_card *card,
178 struct queue_limits *lim)
179{
180 unsigned max_discard;
181
182 max_discard = mmc_calc_max_discard(card);
183 if (!max_discard)
184 return;
185
186 lim->max_hw_discard_sectors = max_discard;
187 if (mmc_card_can_secure_erase_trim(card))
188 lim->max_secure_erase_sectors = max_discard;
189 if (mmc_card_can_trim(card) && card->erased_byte == 0)
190 lim->max_write_zeroes_sectors = max_discard;
191
192 /* granularity must not be greater than max. discard */
193 if (card->pref_erase > max_discard)
194 lim->discard_granularity = SECTOR_SIZE;
195 else
196 lim->discard_granularity = card->pref_erase << 9;
197}
198
199static unsigned short mmc_get_max_segments(struct mmc_host *host)
200{
201 return host->can_dma_map_merge ? MMC_DMA_MAP_MERGE_SEGMENTS :
202 host->max_segs;
203}
204
205static int mmc_mq_init_request(struct blk_mq_tag_set *set, struct request *req,
206 unsigned int hctx_idx, unsigned int numa_node)
207{
208 struct mmc_queue_req *mq_rq = req_to_mmc_queue_req(rq: req);
209 struct mmc_queue *mq = set->driver_data;
210 struct mmc_card *card = mq->card;
211 struct mmc_host *host = card->host;
212
213 mq_rq->sg = mmc_alloc_sg(sg_len: mmc_get_max_segments(host), GFP_KERNEL);
214 if (!mq_rq->sg)
215 return -ENOMEM;
216
217 return 0;
218}
219
220static void mmc_mq_exit_request(struct blk_mq_tag_set *set, struct request *req,
221 unsigned int hctx_idx)
222{
223 struct mmc_queue_req *mq_rq = req_to_mmc_queue_req(rq: req);
224
225 kfree(objp: mq_rq->sg);
226 mq_rq->sg = NULL;
227}
228
229static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
230 const struct blk_mq_queue_data *bd)
231{
232 struct request *req = bd->rq;
233 struct request_queue *q = req->q;
234 struct mmc_queue *mq = q->queuedata;
235 struct mmc_card *card = mq->card;
236 struct mmc_host *host = card->host;
237 enum mmc_issue_type issue_type;
238 enum mmc_issued issued;
239 bool get_card, cqe_retune_ok;
240 blk_status_t ret;
241
242 if (mmc_card_removed(mq->card)) {
243 req->rq_flags |= RQF_QUIET;
244 return BLK_STS_IOERR;
245 }
246
247 issue_type = mmc_issue_type(mq, req);
248
249 spin_lock_irq(lock: &mq->lock);
250
251 if (mq->recovery_needed || mq->busy) {
252 spin_unlock_irq(lock: &mq->lock);
253 return BLK_STS_RESOURCE;
254 }
255
256 switch (issue_type) {
257 case MMC_ISSUE_DCMD:
258 if (mmc_cqe_dcmd_busy(mq)) {
259 mq->cqe_busy |= MMC_CQE_DCMD_BUSY;
260 spin_unlock_irq(lock: &mq->lock);
261 return BLK_STS_RESOURCE;
262 }
263 break;
264 case MMC_ISSUE_ASYNC:
265 if (host->hsq_enabled && mq->in_flight[issue_type] > host->hsq_depth) {
266 spin_unlock_irq(lock: &mq->lock);
267 return BLK_STS_RESOURCE;
268 }
269 break;
270 default:
271 /*
272 * Timeouts are handled by mmc core, and we don't have a host
273 * API to abort requests, so we can't handle the timeout anyway.
274 * However, when the timeout happens, blk_mq_complete_request()
275 * no longer works (to stop the request disappearing under us).
276 * To avoid racing with that, set a large timeout.
277 */
278 req->timeout = 600 * HZ;
279 break;
280 }
281
282 /* Parallel dispatch of requests is not supported at the moment */
283 mq->busy = true;
284
285 mq->in_flight[issue_type] += 1;
286 get_card = (mmc_tot_in_flight(mq) == 1);
287 cqe_retune_ok = (mmc_cqe_qcnt(mq) == 1);
288
289 spin_unlock_irq(lock: &mq->lock);
290
291 if (!(req->rq_flags & RQF_DONTPREP)) {
292 req_to_mmc_queue_req(rq: req)->retries = 0;
293 req->rq_flags |= RQF_DONTPREP;
294 }
295
296 if (get_card)
297 mmc_get_card(card, ctx: &mq->ctx);
298
299 if (host->cqe_enabled) {
300 host->retune_now = host->need_retune && cqe_retune_ok &&
301 !host->hold_retune;
302 }
303
304 blk_mq_start_request(rq: req);
305
306 issued = mmc_blk_mq_issue_rq(mq, req);
307
308 switch (issued) {
309 case MMC_REQ_BUSY:
310 ret = BLK_STS_RESOURCE;
311 break;
312 case MMC_REQ_FAILED_TO_START:
313 ret = BLK_STS_IOERR;
314 break;
315 default:
316 ret = BLK_STS_OK;
317 break;
318 }
319
320 if (issued != MMC_REQ_STARTED) {
321 bool put_card = false;
322
323 spin_lock_irq(lock: &mq->lock);
324 mq->in_flight[issue_type] -= 1;
325 if (mmc_tot_in_flight(mq) == 0)
326 put_card = true;
327 mq->busy = false;
328 spin_unlock_irq(lock: &mq->lock);
329 if (put_card)
330 mmc_put_card(card, ctx: &mq->ctx);
331 } else {
332 WRITE_ONCE(mq->busy, false);
333 }
334
335 return ret;
336}
337
338static const struct blk_mq_ops mmc_mq_ops = {
339 .queue_rq = mmc_mq_queue_rq,
340 .init_request = mmc_mq_init_request,
341 .exit_request = mmc_mq_exit_request,
342 .complete = mmc_blk_mq_complete,
343 .timeout = mmc_mq_timed_out,
344};
345
346static struct gendisk *mmc_alloc_disk(struct mmc_queue *mq,
347 struct mmc_card *card, unsigned int features)
348{
349 struct mmc_host *host = card->host;
350 struct queue_limits lim = {
351 .features = features,
352 };
353 struct gendisk *disk;
354
355 if (mmc_card_can_erase(card))
356 mmc_queue_setup_discard(card, lim: &lim);
357
358 lim.max_hw_sectors = min(host->max_blk_count, host->max_req_size / 512);
359
360 if (mmc_card_mmc(card) && card->ext_csd.data_sector_size)
361 lim.logical_block_size = card->ext_csd.data_sector_size;
362 else
363 lim.logical_block_size = 512;
364
365 WARN_ON_ONCE(lim.logical_block_size != 512 &&
366 lim.logical_block_size != 4096);
367
368 /*
369 * Setting a virt_boundary implicity sets a max_segment_size, so try
370 * to set the hardware one here.
371 */
372 if (host->can_dma_map_merge) {
373 lim.virt_boundary_mask = dma_get_merge_boundary(mmc_dev(host));
374 lim.max_segments = MMC_DMA_MAP_MERGE_SEGMENTS;
375 } else {
376 lim.max_segment_size =
377 round_down(host->max_seg_size, lim.logical_block_size);
378 lim.max_segments = host->max_segs;
379 }
380
381 if (mmc_host_is_spi(host) && host->use_spi_crc)
382 lim.features |= BLK_FEAT_STABLE_WRITES;
383
384 disk = blk_mq_alloc_disk(&mq->tag_set, &lim, mq);
385 if (IS_ERR(ptr: disk))
386 return disk;
387 mq->queue = disk->queue;
388
389 blk_queue_rq_timeout(mq->queue, 60 * HZ);
390
391 if (mmc_dev(host)->dma_parms)
392 dma_set_max_seg_size(mmc_dev(host), size: queue_max_segment_size(q: mq->queue));
393
394 INIT_WORK(&mq->recovery_work, mmc_mq_recovery_handler);
395 INIT_WORK(&mq->complete_work, mmc_blk_mq_complete_work);
396
397 mutex_init(&mq->complete_lock);
398
399 init_waitqueue_head(&mq->wait);
400
401 mmc_crypto_setup_queue(q: mq->queue, host);
402 return disk;
403}
404
405static inline bool mmc_merge_capable(struct mmc_host *host)
406{
407 return host->caps2 & MMC_CAP2_MERGE_CAPABLE;
408}
409
410/* Set queue depth to get a reasonable value for q->nr_requests */
411#define MMC_QUEUE_DEPTH 64
412
413/**
414 * mmc_init_queue - initialise a queue structure.
415 * @mq: mmc queue
416 * @card: mmc card to attach this queue
417 * @features: block layer features (BLK_FEAT_*)
418 *
419 * Initialise a MMC card request queue.
420 */
421struct gendisk *mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
422 unsigned int features)
423{
424 struct mmc_host *host = card->host;
425 struct gendisk *disk;
426 int ret;
427
428 mq->card = card;
429
430 spin_lock_init(&mq->lock);
431
432 memset(&mq->tag_set, 0, sizeof(mq->tag_set));
433 mq->tag_set.ops = &mmc_mq_ops;
434 /*
435 * The queue depth for CQE must match the hardware because the request
436 * tag is used to index the hardware queue.
437 */
438 if (host->cqe_enabled && !host->hsq_enabled)
439 mq->tag_set.queue_depth =
440 min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth);
441 else
442 mq->tag_set.queue_depth = MMC_QUEUE_DEPTH;
443 mq->tag_set.numa_node = NUMA_NO_NODE;
444 mq->tag_set.flags = BLK_MQ_F_BLOCKING;
445 mq->tag_set.nr_hw_queues = 1;
446 mq->tag_set.cmd_size = sizeof(struct mmc_queue_req);
447 mq->tag_set.driver_data = mq;
448
449 /*
450 * Since blk_mq_alloc_tag_set() calls .init_request() of mmc_mq_ops,
451 * the host->can_dma_map_merge should be set before to get max_segs
452 * from mmc_get_max_segments().
453 */
454 if (mmc_merge_capable(host) &&
455 host->max_segs < MMC_DMA_MAP_MERGE_SEGMENTS &&
456 dma_get_merge_boundary(mmc_dev(host)))
457 host->can_dma_map_merge = 1;
458 else
459 host->can_dma_map_merge = 0;
460
461 ret = blk_mq_alloc_tag_set(set: &mq->tag_set);
462 if (ret)
463 return ERR_PTR(error: ret);
464
465
466 disk = mmc_alloc_disk(mq, card, features);
467 if (IS_ERR(ptr: disk))
468 blk_mq_free_tag_set(set: &mq->tag_set);
469 return disk;
470}
471
472void mmc_queue_suspend(struct mmc_queue *mq)
473{
474 blk_mq_quiesce_queue(q: mq->queue);
475
476 /*
477 * The host remains claimed while there are outstanding requests, so
478 * simply claiming and releasing here ensures there are none.
479 */
480 mmc_claim_host(host: mq->card->host);
481 mmc_release_host(host: mq->card->host);
482}
483
484void mmc_queue_resume(struct mmc_queue *mq)
485{
486 blk_mq_unquiesce_queue(q: mq->queue);
487}
488
489void mmc_cleanup_queue(struct mmc_queue *mq)
490{
491 struct request_queue *q = mq->queue;
492
493 /*
494 * The legacy code handled the possibility of being suspended,
495 * so do that here too.
496 */
497 if (blk_queue_quiesced(q))
498 blk_mq_unquiesce_queue(q);
499
500 /*
501 * If the recovery completes the last (and only remaining) request in
502 * the queue, and the card has been removed, we could end up here with
503 * the recovery not quite finished yet, so cancel it.
504 */
505 cancel_work_sync(work: &mq->recovery_work);
506
507 blk_mq_free_tag_set(set: &mq->tag_set);
508
509 /*
510 * A request can be completed before the next request, potentially
511 * leaving a complete_work with nothing to do. Such a work item might
512 * still be queued at this point. Flush it.
513 */
514 flush_work(work: &mq->complete_work);
515
516 mq->card = NULL;
517}
518
519/*
520 * Prepare the sg list(s) to be handed of to the host driver
521 */
522unsigned int mmc_queue_map_sg(struct mmc_queue *mq, struct mmc_queue_req *mqrq)
523{
524 struct request *req = mmc_queue_req_to_req(mqr: mqrq);
525
526 return blk_rq_map_sg(rq: req, sglist: mqrq->sg);
527}
528

source code of linux/drivers/mmc/core/queue.c