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v6.2
  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(&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(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(&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(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(&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(mq->card, &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(&mq->lock);
155	mq->recovery_needed = false;
156	spin_unlock_irq(&mq->lock);
 
 
 
 
157
158	if (host->hsq_enabled)
159		host->cqe_ops->cqe_recovery_finish(host);
160
161	mmc_put_card(mq->card, &mq->ctx);
 
 
 
162
163	blk_mq_run_hw_queues(q, 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 request_queue *q,
178				    struct mmc_card *card)
179{
180	unsigned max_discard;
181
182	max_discard = mmc_calc_max_discard(card);
183	if (!max_discard)
184		return;
185
 
186	blk_queue_max_discard_sectors(q, max_discard);
 
 
187	q->limits.discard_granularity = card->pref_erase << 9;
188	/* granularity must not be greater than max. discard */
189	if (card->pref_erase > max_discard)
190		q->limits.discard_granularity = SECTOR_SIZE;
191	if (mmc_can_secure_erase_trim(card))
192		blk_queue_max_secure_erase_sectors(q, max_discard);
193	if (mmc_can_trim(card) && card->erased_byte == 0)
194		blk_queue_max_write_zeroes_sectors(q, max_discard);
195}
196
197static unsigned short mmc_get_max_segments(struct mmc_host *host)
 
 
198{
199	return host->can_dma_map_merge ? MMC_DMA_MAP_MERGE_SEGMENTS :
200					 host->max_segs;
201}
202
203static int mmc_mq_init_request(struct blk_mq_tag_set *set, struct request *req,
204			       unsigned int hctx_idx, unsigned int numa_node)
205{
206	struct mmc_queue_req *mq_rq = req_to_mmc_queue_req(req);
207	struct mmc_queue *mq = set->driver_data;
208	struct mmc_card *card = mq->card;
209	struct mmc_host *host = card->host;
210
211	mq_rq->sg = mmc_alloc_sg(mmc_get_max_segments(host), GFP_KERNEL);
212	if (!mq_rq->sg)
213		return -ENOMEM;
214
215	return 0;
 
 
 
 
 
 
 
216}
217
218static void mmc_mq_exit_request(struct blk_mq_tag_set *set, struct request *req,
219				unsigned int hctx_idx)
220{
221	struct mmc_queue_req *mq_rq = req_to_mmc_queue_req(req);
 
 
 
 
 
 
 
 
 
 
222
223	kfree(mq_rq->sg);
224	mq_rq->sg = NULL;
225}
 
226
227static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
228				    const struct blk_mq_queue_data *bd)
229{
230	struct request *req = bd->rq;
231	struct request_queue *q = req->q;
232	struct mmc_queue *mq = q->queuedata;
233	struct mmc_card *card = mq->card;
234	struct mmc_host *host = card->host;
235	enum mmc_issue_type issue_type;
236	enum mmc_issued issued;
237	bool get_card, cqe_retune_ok;
238	blk_status_t ret;
239
240	if (mmc_card_removed(mq->card)) {
241		req->rq_flags |= RQF_QUIET;
242		return BLK_STS_IOERR;
 
243	}
244
245	issue_type = mmc_issue_type(mq, req);
246
247	spin_lock_irq(&mq->lock);
248
249	if (mq->recovery_needed || mq->busy) {
250		spin_unlock_irq(&mq->lock);
251		return BLK_STS_RESOURCE;
252	}
253
254	switch (issue_type) {
255	case MMC_ISSUE_DCMD:
256		if (mmc_cqe_dcmd_busy(mq)) {
257			mq->cqe_busy |= MMC_CQE_DCMD_BUSY;
258			spin_unlock_irq(&mq->lock);
259			return BLK_STS_RESOURCE;
260		}
261		break;
262	case MMC_ISSUE_ASYNC:
263		/*
264		 * For MMC host software queue, we only allow 2 requests in
265		 * flight to avoid a long latency.
266		 */
267		if (host->hsq_enabled && mq->in_flight[issue_type] > 2) {
268			spin_unlock_irq(&mq->lock);
269			return BLK_STS_RESOURCE;
270		}
271		break;
272	default:
273		/*
274		 * Timeouts are handled by mmc core, and we don't have a host
275		 * API to abort requests, so we can't handle the timeout anyway.
276		 * However, when the timeout happens, blk_mq_complete_request()
277		 * no longer works (to stop the request disappearing under us).
278		 * To avoid racing with that, set a large timeout.
279		 */
280		req->timeout = 600 * HZ;
281		break;
282	}
283
284	/* Parallel dispatch of requests is not supported at the moment */
285	mq->busy = true;
286
287	mq->in_flight[issue_type] += 1;
288	get_card = (mmc_tot_in_flight(mq) == 1);
289	cqe_retune_ok = (mmc_cqe_qcnt(mq) == 1);
290
291	spin_unlock_irq(&mq->lock);
292
293	if (!(req->rq_flags & RQF_DONTPREP)) {
294		req_to_mmc_queue_req(req)->retries = 0;
295		req->rq_flags |= RQF_DONTPREP;
296	}
297
298	if (get_card)
299		mmc_get_card(card, &mq->ctx);
300
301	if (host->cqe_enabled) {
302		host->retune_now = host->need_retune && cqe_retune_ok &&
303				   !host->hold_retune;
304	}
305
306	blk_mq_start_request(req);
307
308	issued = mmc_blk_mq_issue_rq(mq, req);
309
310	switch (issued) {
311	case MMC_REQ_BUSY:
312		ret = BLK_STS_RESOURCE;
313		break;
314	case MMC_REQ_FAILED_TO_START:
315		ret = BLK_STS_IOERR;
316		break;
317	default:
318		ret = BLK_STS_OK;
319		break;
320	}
321
322	if (issued != MMC_REQ_STARTED) {
323		bool put_card = false;
324
325		spin_lock_irq(&mq->lock);
326		mq->in_flight[issue_type] -= 1;
327		if (mmc_tot_in_flight(mq) == 0)
328			put_card = true;
329		mq->busy = false;
330		spin_unlock_irq(&mq->lock);
331		if (put_card)
332			mmc_put_card(card, &mq->ctx);
333	} else {
334		WRITE_ONCE(mq->busy, false);
335	}
336
337	return ret;
 
338}
339
340static const struct blk_mq_ops mmc_mq_ops = {
341	.queue_rq	= mmc_mq_queue_rq,
342	.init_request	= mmc_mq_init_request,
343	.exit_request	= mmc_mq_exit_request,
344	.complete	= mmc_blk_mq_complete,
345	.timeout	= mmc_mq_timed_out,
346};
347
348static void mmc_setup_queue(struct mmc_queue *mq, struct mmc_card *card)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
349{
350	struct mmc_host *host = card->host;
351	unsigned block_size = 512;
 
 
 
 
 
352
353	blk_queue_flag_set(QUEUE_FLAG_NONROT, mq->queue);
354	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, mq->queue);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
355	if (mmc_can_erase(card))
356		mmc_queue_setup_discard(mq->queue, card);
357
358	if (!mmc_dev(host)->dma_mask || !*mmc_dev(host)->dma_mask)
359		blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_HIGH);
360	blk_queue_max_hw_sectors(mq->queue,
361		min(host->max_blk_count, host->max_req_size / 512));
362	if (host->can_dma_map_merge)
363		WARN(!blk_queue_can_use_dma_map_merging(mq->queue,
364							mmc_dev(host)),
365		     "merging was advertised but not possible");
366	blk_queue_max_segments(mq->queue, mmc_get_max_segments(host));
367
368	if (mmc_card_mmc(card) && card->ext_csd.data_sector_size) {
369		block_size = card->ext_csd.data_sector_size;
370		WARN_ON(block_size != 512 && block_size != 4096);
 
 
 
 
 
 
 
 
 
 
 
 
371	}
 
372
373	blk_queue_logical_block_size(mq->queue, block_size);
374	/*
375	 * After blk_queue_can_use_dma_map_merging() was called with succeed,
376	 * since it calls blk_queue_virt_boundary(), the mmc should not call
377	 * both blk_queue_max_segment_size().
378	 */
379	if (!host->can_dma_map_merge)
380		blk_queue_max_segment_size(mq->queue,
381			round_down(host->max_seg_size, block_size));
382
383	dma_set_max_seg_size(mmc_dev(host), queue_max_segment_size(mq->queue));
 
 
 
384
385	INIT_WORK(&mq->recovery_work, mmc_mq_recovery_handler);
386	INIT_WORK(&mq->complete_work, mmc_blk_mq_complete_work);
387
388	mutex_init(&mq->complete_lock);
 
389
390	init_waitqueue_head(&mq->wait);
 
 
 
391
392	mmc_crypto_setup_queue(mq->queue, host);
393}
394
395static inline bool mmc_merge_capable(struct mmc_host *host)
396{
397	return host->caps2 & MMC_CAP2_MERGE_CAPABLE;
 
 
 
 
398}
399
400/* Set queue depth to get a reasonable value for q->nr_requests */
401#define MMC_QUEUE_DEPTH 64
402
403/**
404 * mmc_init_queue - initialise a queue structure.
405 * @mq: mmc queue
406 * @card: mmc card to attach this queue
407 *
408 * Initialise a MMC card request queue.
409 */
410struct gendisk *mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
411{
412	struct mmc_host *host = card->host;
413	struct gendisk *disk;
414	int ret;
415
416	mq->card = card;
417	
418	spin_lock_init(&mq->lock);
419
420	memset(&mq->tag_set, 0, sizeof(mq->tag_set));
421	mq->tag_set.ops = &mmc_mq_ops;
422	/*
423	 * The queue depth for CQE must match the hardware because the request
424	 * tag is used to index the hardware queue.
425	 */
426	if (host->cqe_enabled && !host->hsq_enabled)
427		mq->tag_set.queue_depth =
428			min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth);
429	else
430		mq->tag_set.queue_depth = MMC_QUEUE_DEPTH;
431	mq->tag_set.numa_node = NUMA_NO_NODE;
432	mq->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING;
433	mq->tag_set.nr_hw_queues = 1;
434	mq->tag_set.cmd_size = sizeof(struct mmc_queue_req);
435	mq->tag_set.driver_data = mq;
436
437	/*
438	 * Since blk_mq_alloc_tag_set() calls .init_request() of mmc_mq_ops,
439	 * the host->can_dma_map_merge should be set before to get max_segs
440	 * from mmc_get_max_segments().
441	 */
442	if (mmc_merge_capable(host) &&
443	    host->max_segs < MMC_DMA_MAP_MERGE_SEGMENTS &&
444	    dma_get_merge_boundary(mmc_dev(host)))
445		host->can_dma_map_merge = 1;
446	else
447		host->can_dma_map_merge = 0;
448
449	ret = blk_mq_alloc_tag_set(&mq->tag_set);
450	if (ret)
451		return ERR_PTR(ret);
452		
453
454	disk = blk_mq_alloc_disk(&mq->tag_set, mq);
455	if (IS_ERR(disk)) {
456		blk_mq_free_tag_set(&mq->tag_set);
457		return disk;
458	}
459	mq->queue = disk->queue;
460
461	if (mmc_host_is_spi(host) && host->use_spi_crc)
462		blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, mq->queue);
463	blk_queue_rq_timeout(mq->queue, 60 * HZ);
464
465	mmc_setup_queue(mq, card);
466	return disk;
467}
 
468
 
 
 
 
 
 
 
 
469void mmc_queue_suspend(struct mmc_queue *mq)
470{
471	blk_mq_quiesce_queue(mq->queue);
 
472
473	/*
474	 * The host remains claimed while there are outstanding requests, so
475	 * simply claiming and releasing here ensures there are none.
476	 */
477	mmc_claim_host(mq->card->host);
478	mmc_release_host(mq->card->host);
 
 
 
479}
480
 
 
 
 
481void mmc_queue_resume(struct mmc_queue *mq)
482{
483	blk_mq_unquiesce_queue(mq->queue);
 
 
 
 
 
 
 
 
 
 
 
484}
485
486void mmc_cleanup_queue(struct mmc_queue *mq)
 
 
 
487{
488	struct request_queue *q = mq->queue;
 
 
 
489
490	/*
491	 * The legacy code handled the possibility of being suspended,
492	 * so do that here too.
493	 */
494	if (blk_queue_quiesced(q))
495		blk_mq_unquiesce_queue(q);
496
497	/*
498	 * If the recovery completes the last (and only remaining) request in
499	 * the queue, and the card has been removed, we could end up here with
500	 * the recovery not quite finished yet, so cancel it.
501	 */
502	cancel_work_sync(&mq->recovery_work);
503
504	blk_mq_free_tag_set(&mq->tag_set);
505
506	/*
507	 * A request can be completed before the next request, potentially
508	 * leaving a complete_work with nothing to do. Such a work item might
509	 * still be queued at this point. Flush it.
510	 */
511	flush_work(&mq->complete_work);
512
513	mq->card = NULL;
 
 
514}
515
516/*
517 * Prepare the sg list(s) to be handed of to the host driver
 
518 */
519unsigned int mmc_queue_map_sg(struct mmc_queue *mq, struct mmc_queue_req *mqrq)
520{
521	struct request *req = mmc_queue_req_to_req(mqrq);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
522
523	return blk_rq_map_sg(mq->queue, req, mqrq->sg);
 
524}
v4.10.11
 
  1/*
  2 *  Copyright (C) 2003 Russell King, All Rights Reserved.
  3 *  Copyright 2006-2007 Pierre Ossman
  4 *
  5 * This program is free software; you can redistribute it and/or modify
  6 * it under the terms of the GNU General Public License version 2 as
  7 * published by the Free Software Foundation.
  8 *
  9 */
 10#include <linux/slab.h>
 11#include <linux/module.h>
 12#include <linux/blkdev.h>
 13#include <linux/freezer.h>
 14#include <linux/kthread.h>
 15#include <linux/scatterlist.h>
 16#include <linux/dma-mapping.h>
 
 17
 18#include <linux/mmc/card.h>
 19#include <linux/mmc/host.h>
 20
 21#include "queue.h"
 22#include "block.h"
 
 
 
 
 
 
 
 
 
 
 
 
 23
 24#define MMC_QUEUE_BOUNCESZ	65536
 
 
 
 
 25
 26/*
 27 * Prepare a MMC request. This just filters out odd stuff.
 28 */
 29static int mmc_prep_request(struct request_queue *q, struct request *req)
 30{
 31	struct mmc_queue *mq = q->queuedata;
 
 32
 33	/*
 34	 * We only like normal block requests and discards.
 35	 */
 36	if (req->cmd_type != REQ_TYPE_FS && req_op(req) != REQ_OP_DISCARD &&
 37	    req_op(req) != REQ_OP_SECURE_ERASE) {
 38		blk_dump_rq_flags(req, "MMC bad request");
 39		return BLKPREP_KILL;
 
 
 
 
 
 
 
 40	}
 
 
 
 
 
 41
 42	if (mq && (mmc_card_removed(mq->card) || mmc_access_rpmb(mq)))
 43		return BLKPREP_KILL;
 44
 45	req->rq_flags |= RQF_DONTPREP;
 
 46
 47	return BLKPREP_OK;
 48}
 49
 50static int mmc_queue_thread(void *d)
 51{
 52	struct mmc_queue *mq = d;
 53	struct request_queue *q = mq->queue;
 54	struct mmc_context_info *cntx = &mq->card->host->context_info;
 
 
 55
 56	current->flags |= PF_MEMALLOC;
 
 
 
 
 
 
 
 57
 58	down(&mq->thread_sem);
 59	do {
 60		struct request *req = NULL;
 61
 62		spin_lock_irq(q->queue_lock);
 63		set_current_state(TASK_INTERRUPTIBLE);
 64		req = blk_fetch_request(q);
 65		mq->asleep = false;
 66		cntx->is_waiting_last_req = false;
 67		cntx->is_new_req = false;
 68		if (!req) {
 69			/*
 70			 * Dispatch queue is empty so set flags for
 71			 * mmc_request_fn() to wake us up.
 72			 */
 73			if (mq->mqrq_prev->req)
 74				cntx->is_waiting_last_req = true;
 75			else
 76				mq->asleep = true;
 
 
 77		}
 78		mq->mqrq_cur->req = req;
 79		spin_unlock_irq(q->queue_lock);
 
 
 
 
 
 80
 81		if (req || mq->mqrq_prev->req) {
 82			bool req_is_special = mmc_req_is_special(req);
 
 
 
 
 
 
 83
 84			set_current_state(TASK_RUNNING);
 85			mmc_blk_issue_rq(mq, req);
 86			cond_resched();
 87			if (mq->flags & MMC_QUEUE_NEW_REQUEST) {
 88				mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
 89				continue; /* fetch again */
 90			}
 91
 92			/*
 93			 * Current request becomes previous request
 94			 * and vice versa.
 95			 * In case of special requests, current request
 96			 * has been finished. Do not assign it to previous
 97			 * request.
 98			 */
 99			if (req_is_special)
100				mq->mqrq_cur->req = NULL;
101
102			mq->mqrq_prev->brq.mrq.data = NULL;
103			mq->mqrq_prev->req = NULL;
104			swap(mq->mqrq_prev, mq->mqrq_cur);
105		} else {
106			if (kthread_should_stop()) {
107				set_current_state(TASK_RUNNING);
108				break;
109			}
110			up(&mq->thread_sem);
111			schedule();
112			down(&mq->thread_sem);
113		}
114	} while (1);
115	up(&mq->thread_sem);
116
117	return 0;
118}
119
120/*
121 * Generic MMC request handler.  This is called for any queue on a
122 * particular host.  When the host is not busy, we look for a request
123 * on any queue on this host, and attempt to issue it.  This may
124 * not be the queue we were asked to process.
125 */
126static void mmc_request_fn(struct request_queue *q)
127{
128	struct mmc_queue *mq = q->queuedata;
129	struct request *req;
130	struct mmc_context_info *cntx;
 
 
 
 
 
 
 
 
 
 
 
 
131
132	if (!mq) {
133		while ((req = blk_fetch_request(q)) != NULL) {
134			req->rq_flags |= RQF_QUIET;
135			__blk_end_request_all(req, -EIO);
136		}
137		return;
138	}
139
140	cntx = &mq->card->host->context_info;
 
141
142	if (cntx->is_waiting_last_req) {
143		cntx->is_new_req = true;
144		wake_up_interruptible(&cntx->wait);
145	}
146
147	if (mq->asleep)
148		wake_up_process(mq->thread);
149}
150
151static struct scatterlist *mmc_alloc_sg(int sg_len, int *err)
152{
153	struct scatterlist *sg;
154
155	sg = kmalloc(sizeof(struct scatterlist)*sg_len, GFP_KERNEL);
156	if (!sg)
157		*err = -ENOMEM;
158	else {
159		*err = 0;
160		sg_init_table(sg, sg_len);
161	}
162
163	return sg;
164}
165
166static void mmc_queue_setup_discard(struct request_queue *q,
167				    struct mmc_card *card)
168{
169	unsigned max_discard;
170
171	max_discard = mmc_calc_max_discard(card);
172	if (!max_discard)
173		return;
174
175	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
176	blk_queue_max_discard_sectors(q, max_discard);
177	if (card->erased_byte == 0 && !mmc_can_discard(card))
178		q->limits.discard_zeroes_data = 1;
179	q->limits.discard_granularity = card->pref_erase << 9;
180	/* granularity must not be greater than max. discard */
181	if (card->pref_erase > max_discard)
182		q->limits.discard_granularity = 0;
183	if (mmc_can_secure_erase_trim(card))
184		queue_flag_set_unlocked(QUEUE_FLAG_SECERASE, q);
 
 
185}
186
187#ifdef CONFIG_MMC_BLOCK_BOUNCE
188static bool mmc_queue_alloc_bounce_bufs(struct mmc_queue *mq,
189					unsigned int bouncesz)
190{
191	int i;
 
 
192
193	for (i = 0; i < mq->qdepth; i++) {
194		mq->mqrq[i].bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
195		if (!mq->mqrq[i].bounce_buf)
196			goto out_err;
197	}
 
 
198
199	return true;
 
 
200
201out_err:
202	while (--i >= 0) {
203		kfree(mq->mqrq[i].bounce_buf);
204		mq->mqrq[i].bounce_buf = NULL;
205	}
206	pr_warn("%s: unable to allocate bounce buffers\n",
207		mmc_card_name(mq->card));
208	return false;
209}
210
211static int mmc_queue_alloc_bounce_sgs(struct mmc_queue *mq,
212				      unsigned int bouncesz)
213{
214	int i, ret;
215
216	for (i = 0; i < mq->qdepth; i++) {
217		mq->mqrq[i].sg = mmc_alloc_sg(1, &ret);
218		if (ret)
219			return ret;
220
221		mq->mqrq[i].bounce_sg = mmc_alloc_sg(bouncesz / 512, &ret);
222		if (ret)
223			return ret;
224	}
225
226	return 0;
 
227}
228#endif
229
230static int mmc_queue_alloc_sgs(struct mmc_queue *mq, int max_segs)
 
231{
232	int i, ret;
 
 
 
 
 
 
 
 
233
234	for (i = 0; i < mq->qdepth; i++) {
235		mq->mqrq[i].sg = mmc_alloc_sg(max_segs, &ret);
236		if (ret)
237			return ret;
238	}
239
240	return 0;
241}
 
242
243static void mmc_queue_req_free_bufs(struct mmc_queue_req *mqrq)
244{
245	kfree(mqrq->bounce_sg);
246	mqrq->bounce_sg = NULL;
247
248	kfree(mqrq->sg);
249	mqrq->sg = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
250
251	kfree(mqrq->bounce_buf);
252	mqrq->bounce_buf = NULL;
253}
254
255static void mmc_queue_reqs_free_bufs(struct mmc_queue *mq)
256{
257	int i;
 
 
 
 
258
259	for (i = 0; i < mq->qdepth; i++)
260		mmc_queue_req_free_bufs(&mq->mqrq[i]);
261}
262
263/**
264 * mmc_init_queue - initialise a queue structure.
265 * @mq: mmc queue
266 * @card: mmc card to attach this queue
267 * @lock: queue lock
268 * @subname: partition subname
269 *
270 * Initialise a MMC card request queue.
271 */
272int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
273		   spinlock_t *lock, const char *subname)
274{
275	struct mmc_host *host = card->host;
276	u64 limit = BLK_BOUNCE_HIGH;
277	bool bounce = false;
278	int ret = -ENOMEM;
279
280	if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
281		limit = (u64)dma_max_pfn(mmc_dev(host)) << PAGE_SHIFT;
282
283	mq->card = card;
284	mq->queue = blk_init_queue(mmc_request_fn, lock);
285	if (!mq->queue)
286		return -ENOMEM;
287
288	mq->qdepth = 2;
289	mq->mqrq = kcalloc(mq->qdepth, sizeof(struct mmc_queue_req),
290			   GFP_KERNEL);
291	if (!mq->mqrq)
292		goto blk_cleanup;
293	mq->mqrq_cur = &mq->mqrq[0];
294	mq->mqrq_prev = &mq->mqrq[1];
295	mq->queue->queuedata = mq;
296
297	blk_queue_prep_rq(mq->queue, mmc_prep_request);
298	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
299	queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, mq->queue);
300	if (mmc_can_erase(card))
301		mmc_queue_setup_discard(mq->queue, card);
302
303#ifdef CONFIG_MMC_BLOCK_BOUNCE
304	if (host->max_segs == 1) {
305		unsigned int bouncesz;
306
307		bouncesz = MMC_QUEUE_BOUNCESZ;
308
309		if (bouncesz > host->max_req_size)
310			bouncesz = host->max_req_size;
311		if (bouncesz > host->max_seg_size)
312			bouncesz = host->max_seg_size;
313		if (bouncesz > (host->max_blk_count * 512))
314			bouncesz = host->max_blk_count * 512;
315
316		if (bouncesz > 512 &&
317		    mmc_queue_alloc_bounce_bufs(mq, bouncesz)) {
318			blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_ANY);
319			blk_queue_max_hw_sectors(mq->queue, bouncesz / 512);
320			blk_queue_max_segments(mq->queue, bouncesz / 512);
321			blk_queue_max_segment_size(mq->queue, bouncesz);
322
323			ret = mmc_queue_alloc_bounce_sgs(mq, bouncesz);
324			if (ret)
325				goto cleanup_queue;
326			bounce = true;
327		}
328	}
329#endif
330
331	if (!bounce) {
332		blk_queue_bounce_limit(mq->queue, limit);
333		blk_queue_max_hw_sectors(mq->queue,
334			min(host->max_blk_count, host->max_req_size / 512));
335		blk_queue_max_segments(mq->queue, host->max_segs);
336		blk_queue_max_segment_size(mq->queue, host->max_seg_size);
 
 
 
337
338		ret = mmc_queue_alloc_sgs(mq, host->max_segs);
339		if (ret)
340			goto cleanup_queue;
341	}
342
343	sema_init(&mq->thread_sem, 1);
 
344
345	mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd/%d%s",
346		host->index, subname ? subname : "");
347
348	if (IS_ERR(mq->thread)) {
349		ret = PTR_ERR(mq->thread);
350		goto cleanup_queue;
351	}
352
353	return 0;
 
354
355 cleanup_queue:
356	mmc_queue_reqs_free_bufs(mq);
357	kfree(mq->mqrq);
358	mq->mqrq = NULL;
359blk_cleanup:
360	blk_cleanup_queue(mq->queue);
361	return ret;
362}
363
364void mmc_cleanup_queue(struct mmc_queue *mq)
 
 
 
 
 
 
 
 
 
 
365{
366	struct request_queue *q = mq->queue;
367	unsigned long flags;
 
368
369	/* Make sure the queue isn't suspended, as that will deadlock */
370	mmc_queue_resume(mq);
 
371
372	/* Then terminate our worker thread */
373	kthread_stop(mq->thread);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
374
375	/* Empty the queue */
376	spin_lock_irqsave(q->queue_lock, flags);
377	q->queuedata = NULL;
378	blk_start_queue(q);
379	spin_unlock_irqrestore(q->queue_lock, flags);
380
381	mmc_queue_reqs_free_bufs(mq);
382	kfree(mq->mqrq);
383	mq->mqrq = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
384
385	mq->card = NULL;
 
386}
387EXPORT_SYMBOL(mmc_cleanup_queue);
388
389/**
390 * mmc_queue_suspend - suspend a MMC request queue
391 * @mq: MMC queue to suspend
392 *
393 * Stop the block request queue, and wait for our thread to
394 * complete any outstanding requests.  This ensures that we
395 * won't suspend while a request is being processed.
396 */
397void mmc_queue_suspend(struct mmc_queue *mq)
398{
399	struct request_queue *q = mq->queue;
400	unsigned long flags;
401
402	if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
403		mq->flags |= MMC_QUEUE_SUSPENDED;
404
405		spin_lock_irqsave(q->queue_lock, flags);
406		blk_stop_queue(q);
407		spin_unlock_irqrestore(q->queue_lock, flags);
408
409		down(&mq->thread_sem);
410	}
411}
412
413/**
414 * mmc_queue_resume - resume a previously suspended MMC request queue
415 * @mq: MMC queue to resume
416 */
417void mmc_queue_resume(struct mmc_queue *mq)
418{
419	struct request_queue *q = mq->queue;
420	unsigned long flags;
421
422	if (mq->flags & MMC_QUEUE_SUSPENDED) {
423		mq->flags &= ~MMC_QUEUE_SUSPENDED;
424
425		up(&mq->thread_sem);
426
427		spin_lock_irqsave(q->queue_lock, flags);
428		blk_start_queue(q);
429		spin_unlock_irqrestore(q->queue_lock, flags);
430	}
431}
432
433/*
434 * Prepare the sg list(s) to be handed of to the host driver
435 */
436unsigned int mmc_queue_map_sg(struct mmc_queue *mq, struct mmc_queue_req *mqrq)
437{
438	unsigned int sg_len;
439	size_t buflen;
440	struct scatterlist *sg;
441	int i;
442
443	if (!mqrq->bounce_buf)
444		return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);
 
 
 
 
445
446	sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg);
 
 
 
 
 
447
448	mqrq->bounce_sg_len = sg_len;
449
450	buflen = 0;
451	for_each_sg(mqrq->bounce_sg, sg, sg_len, i)
452		buflen += sg->length;
 
 
 
453
454	sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen);
455
456	return 1;
457}
458
459/*
460 * If writing, bounce the data to the buffer before the request
461 * is sent to the host driver
462 */
463void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq)
464{
465	if (!mqrq->bounce_buf)
466		return;
467
468	if (rq_data_dir(mqrq->req) != WRITE)
469		return;
470
471	sg_copy_to_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
472		mqrq->bounce_buf, mqrq->sg[0].length);
473}
474
475/*
476 * If reading, bounce the data from the buffer after the request
477 * has been handled by the host driver
478 */
479void mmc_queue_bounce_post(struct mmc_queue_req *mqrq)
480{
481	if (!mqrq->bounce_buf)
482		return;
483
484	if (rq_data_dir(mqrq->req) != READ)
485		return;
486
487	sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
488		mqrq->bounce_buf, mqrq->sg[0].length);
489}