[mirror_ubuntu-artful-kernel.git] / drivers / mmc / card / queue.c

/*
 *  linux/drivers/mmc/card/queue.c
 *
 *  Copyright (C) 2003 Russell King, All Rights Reserved.
 *  Copyright 2006-2007 Pierre Ossman
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/freezer.h>
#include <linux/kthread.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>

#include "queue.h"
#include "block.h"

#define MMC_QUEUE_BOUNCESZ	65536

/*
 * Prepare a MMC request. This just filters out odd stuff.
 */
static int mmc_prep_request(struct request_queue *q, struct request *req)
{
	struct mmc_queue *mq = q->queuedata;

	/*
	 * We only like normal block requests and discards.
	 */
	if (req->cmd_type != REQ_TYPE_FS && req_op(req) != REQ_OP_DISCARD &&
	    req_op(req) != REQ_OP_SECURE_ERASE) {
		blk_dump_rq_flags(req, "MMC bad request");
		return BLKPREP_KILL;
	}

	if (mq && (mmc_card_removed(mq->card) || mmc_access_rpmb(mq)))
		return BLKPREP_KILL;

	req->cmd_flags |= REQ_DONTPREP;

	return BLKPREP_OK;
}

static int mmc_queue_thread(void *d)
{
	struct mmc_queue *mq = d;
	struct request_queue *q = mq->queue;
	struct mmc_context_info *cntx = &mq->card->host->context_info;

	current->flags |= PF_MEMALLOC;

	down(&mq->thread_sem);
	do {
		struct request *req = NULL;

		spin_lock_irq(q->queue_lock);
		set_current_state(TASK_INTERRUPTIBLE);
		req = blk_fetch_request(q);
		mq->asleep = false;
		cntx->is_waiting_last_req = false;
		cntx->is_new_req = false;
		if (!req) {
			/*
			 * Dispatch queue is empty so set flags for
			 * mmc_request_fn() to wake us up.
			 */
			if (mq->mqrq_prev->req)
				cntx->is_waiting_last_req = true;
			else
				mq->asleep = true;
		}
		mq->mqrq_cur->req = req;
		spin_unlock_irq(q->queue_lock);

		if (req || mq->mqrq_prev->req) {
			bool req_is_special = mmc_req_is_special(req);

			set_current_state(TASK_RUNNING);
			mmc_blk_issue_rq(mq, req);
			cond_resched();
			if (mq->flags & MMC_QUEUE_NEW_REQUEST) {
				mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
				continue; /* fetch again */
			}

			/*
			 * Current request becomes previous request
			 * and vice versa.
			 * In case of special requests, current request
			 * has been finished. Do not assign it to previous
			 * request.
			 */
			if (req_is_special)
				mq->mqrq_cur->req = NULL;

			mq->mqrq_prev->brq.mrq.data = NULL;
			mq->mqrq_prev->req = NULL;
			swap(mq->mqrq_prev, mq->mqrq_cur);
		} else {
			if (kthread_should_stop()) {
				set_current_state(TASK_RUNNING);
				break;
			}
			up(&mq->thread_sem);
			schedule();
			down(&mq->thread_sem);
		}
	} while (1);
	up(&mq->thread_sem);

	return 0;
}

/*
 * Generic MMC request handler.  This is called for any queue on a
 * particular host.  When the host is not busy, we look for a request
 * on any queue on this host, and attempt to issue it.  This may
 * not be the queue we were asked to process.
 */
static void mmc_request_fn(struct request_queue *q)
{
	struct mmc_queue *mq = q->queuedata;
	struct request *req;
	struct mmc_context_info *cntx;

	if (!mq) {
		while ((req = blk_fetch_request(q)) != NULL) {
			req->cmd_flags |= REQ_QUIET;
			__blk_end_request_all(req, -EIO);
		}
		return;
	}

	cntx = &mq->card->host->context_info;

	if (cntx->is_waiting_last_req) {
		cntx->is_new_req = true;
		wake_up_interruptible(&cntx->wait);
	}

	if (mq->asleep)
		wake_up_process(mq->thread);
}

static struct scatterlist *mmc_alloc_sg(int sg_len, int *err)
{
	struct scatterlist *sg;

	sg = kmalloc(sizeof(struct scatterlist)*sg_len, GFP_KERNEL);
	if (!sg)
		*err = -ENOMEM;
	else {
		*err = 0;
		sg_init_table(sg, sg_len);
	}

	return sg;
}

static void mmc_queue_setup_discard(struct request_queue *q,
				    struct mmc_card *card)
{
	unsigned max_discard;

	max_discard = mmc_calc_max_discard(card);
	if (!max_discard)
		return;

	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
	blk_queue_max_discard_sectors(q, max_discard);
	if (card->erased_byte == 0 && !mmc_can_discard(card))
		q->limits.discard_zeroes_data = 1;
	q->limits.discard_granularity = card->pref_erase << 9;
	/* granularity must not be greater than max. discard */
	if (card->pref_erase > max_discard)
		q->limits.discard_granularity = 0;
	if (mmc_can_secure_erase_trim(card))
		queue_flag_set_unlocked(QUEUE_FLAG_SECERASE, q);
}

#ifdef CONFIG_MMC_BLOCK_BOUNCE
static bool mmc_queue_alloc_bounce_bufs(struct mmc_queue *mq,
					unsigned int bouncesz)
{
	int i;

	for (i = 0; i < mq->qdepth; i++) {
		mq->mqrq[i].bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
		if (!mq->mqrq[i].bounce_buf)
			goto out_err;
	}

	return true;

out_err:
	while (--i >= 0) {
		kfree(mq->mqrq[i].bounce_buf);
		mq->mqrq[i].bounce_buf = NULL;
	}
	pr_warn("%s: unable to allocate bounce buffers\n",
		mmc_card_name(mq->card));
	return false;
}

static int mmc_queue_alloc_bounce_sgs(struct mmc_queue *mq,
				      unsigned int bouncesz)
{
	int i, ret;

	for (i = 0; i < mq->qdepth; i++) {
		mq->mqrq[i].sg = mmc_alloc_sg(1, &ret);
		if (ret)
			return ret;

		mq->mqrq[i].bounce_sg = mmc_alloc_sg(bouncesz / 512, &ret);
		if (ret)
			return ret;
	}

	return 0;
}
#endif

static int mmc_queue_alloc_sgs(struct mmc_queue *mq, int max_segs)
{
	int i, ret;

	for (i = 0; i < mq->qdepth; i++) {
		mq->mqrq[i].sg = mmc_alloc_sg(max_segs, &ret);
		if (ret)
			return ret;
	}

	return 0;
}

static void mmc_queue_req_free_bufs(struct mmc_queue_req *mqrq)
{
	kfree(mqrq->bounce_sg);
	mqrq->bounce_sg = NULL;

	kfree(mqrq->sg);
	mqrq->sg = NULL;

	kfree(mqrq->bounce_buf);
	mqrq->bounce_buf = NULL;
}

static void mmc_queue_reqs_free_bufs(struct mmc_queue *mq)
{
	int i;

	for (i = 0; i < mq->qdepth; i++)
		mmc_queue_req_free_bufs(&mq->mqrq[i]);
}

/**
 * mmc_init_queue - initialise a queue structure.
 * @mq: mmc queue
 * @card: mmc card to attach this queue
 * @lock: queue lock
 * @subname: partition subname
 *
 * Initialise a MMC card request queue.
 */
int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
		   spinlock_t *lock, const char *subname)
{
	struct mmc_host *host = card->host;
	u64 limit = BLK_BOUNCE_HIGH;
	bool bounce = false;
	int ret = -ENOMEM;

	if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
		limit = (u64)dma_max_pfn(mmc_dev(host)) << PAGE_SHIFT;

	mq->card = card;
	mq->queue = blk_init_queue(mmc_request_fn, lock);
	if (!mq->queue)
		return -ENOMEM;

	mq->qdepth = 2;
	mq->mqrq = kcalloc(mq->qdepth, sizeof(struct mmc_queue_req),
			   GFP_KERNEL);
	if (!mq->mqrq)
		goto blk_cleanup;
	mq->mqrq_cur = &mq->mqrq[0];
	mq->mqrq_prev = &mq->mqrq[1];
	mq->queue->queuedata = mq;

	blk_queue_prep_rq(mq->queue, mmc_prep_request);
	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
	queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, mq->queue);
	if (mmc_can_erase(card))
		mmc_queue_setup_discard(mq->queue, card);

#ifdef CONFIG_MMC_BLOCK_BOUNCE
	if (host->max_segs == 1) {
		unsigned int bouncesz;

		bouncesz = MMC_QUEUE_BOUNCESZ;

		if (bouncesz > host->max_req_size)
			bouncesz = host->max_req_size;
		if (bouncesz > host->max_seg_size)
			bouncesz = host->max_seg_size;
		if (bouncesz > (host->max_blk_count * 512))
			bouncesz = host->max_blk_count * 512;

		if (bouncesz > 512 &&
		    mmc_queue_alloc_bounce_bufs(mq, bouncesz)) {
			blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_ANY);
			blk_queue_max_hw_sectors(mq->queue, bouncesz / 512);
			blk_queue_max_segments(mq->queue, bouncesz / 512);
			blk_queue_max_segment_size(mq->queue, bouncesz);

			ret = mmc_queue_alloc_bounce_sgs(mq, bouncesz);
			if (ret)
				goto cleanup_queue;
			bounce = true;
		}
	}
#endif

	if (!bounce) {
		blk_queue_bounce_limit(mq->queue, limit);
		blk_queue_max_hw_sectors(mq->queue,
			min(host->max_blk_count, host->max_req_size / 512));
		blk_queue_max_segments(mq->queue, host->max_segs);
		blk_queue_max_segment_size(mq->queue, host->max_seg_size);

		ret = mmc_queue_alloc_sgs(mq, host->max_segs);
		if (ret)
			goto cleanup_queue;
	}

	sema_init(&mq->thread_sem, 1);

	mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd/%d%s",
		host->index, subname ? subname : "");

	if (IS_ERR(mq->thread)) {
		ret = PTR_ERR(mq->thread);
		goto cleanup_queue;
	}

	return 0;

 cleanup_queue:
	mmc_queue_reqs_free_bufs(mq);
	kfree(mq->mqrq);
	mq->mqrq = NULL;
blk_cleanup:
	blk_cleanup_queue(mq->queue);
	return ret;
}

void mmc_cleanup_queue(struct mmc_queue *mq)
{
	struct request_queue *q = mq->queue;
	unsigned long flags;

	/* Make sure the queue isn't suspended, as that will deadlock */
	mmc_queue_resume(mq);

	/* Then terminate our worker thread */
	kthread_stop(mq->thread);

	/* Empty the queue */
	spin_lock_irqsave(q->queue_lock, flags);
	q->queuedata = NULL;
	blk_start_queue(q);
	spin_unlock_irqrestore(q->queue_lock, flags);

	mmc_queue_reqs_free_bufs(mq);
	kfree(mq->mqrq);
	mq->mqrq = NULL;

	mq->card = NULL;
}
EXPORT_SYMBOL(mmc_cleanup_queue);

/**
 * mmc_queue_suspend - suspend a MMC request queue
 * @mq: MMC queue to suspend
 *
 * Stop the block request queue, and wait for our thread to
 * complete any outstanding requests.  This ensures that we
 * won't suspend while a request is being processed.
 */
void mmc_queue_suspend(struct mmc_queue *mq)
{
	struct request_queue *q = mq->queue;
	unsigned long flags;

	if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
		mq->flags |= MMC_QUEUE_SUSPENDED;

		spin_lock_irqsave(q->queue_lock, flags);
		blk_stop_queue(q);
		spin_unlock_irqrestore(q->queue_lock, flags);

		down(&mq->thread_sem);
	}
}

/**
 * mmc_queue_resume - resume a previously suspended MMC request queue
 * @mq: MMC queue to resume
 */
void mmc_queue_resume(struct mmc_queue *mq)
{
	struct request_queue *q = mq->queue;
	unsigned long flags;

	if (mq->flags & MMC_QUEUE_SUSPENDED) {
		mq->flags &= ~MMC_QUEUE_SUSPENDED;

		up(&mq->thread_sem);

		spin_lock_irqsave(q->queue_lock, flags);
		blk_start_queue(q);
		spin_unlock_irqrestore(q->queue_lock, flags);
	}
}

/*
 * Prepare the sg list(s) to be handed of to the host driver
 */
unsigned int mmc_queue_map_sg(struct mmc_queue *mq, struct mmc_queue_req *mqrq)
{
	unsigned int sg_len;
	size_t buflen;
	struct scatterlist *sg;
	int i;

	if (!mqrq->bounce_buf)
		return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);

	BUG_ON(!mqrq->bounce_sg);

	sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg);

	mqrq->bounce_sg_len = sg_len;

	buflen = 0;
	for_each_sg(mqrq->bounce_sg, sg, sg_len, i)
		buflen += sg->length;

	sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen);

	return 1;
}

/*
 * If writing, bounce the data to the buffer before the request
 * is sent to the host driver
 */
void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq)
{
	if (!mqrq->bounce_buf)
		return;

	if (rq_data_dir(mqrq->req) != WRITE)
		return;

	sg_copy_to_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
		mqrq->bounce_buf, mqrq->sg[0].length);
}

/*
 * If reading, bounce the data from the buffer after the request
 * has been handled by the host driver
 */
void mmc_queue_bounce_post(struct mmc_queue_req *mqrq)
{
	if (!mqrq->bounce_buf)
		return;

	if (rq_data_dir(mqrq->req) != READ)
		return;

	sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
		mqrq->bounce_buf, mqrq->sg[0].length);
}
Commit	Line	Data
1da177e4	1	/*
70f10482	2	* linux/drivers/mmc/card/queue.c
1da177e4 LT	3	*
1da177e4 LT	4	* Copyright (C) 2003 Russell King, All Rights Reserved.
98ac2162	5	* Copyright 2006-2007 Pierre Ossman
1da177e4 LT	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	*/
5a0e3ad6	12	#include <linux/slab.h>
1da177e4 LT	13	#include <linux/module.h>
1da177e4 LT	14	#include <linux/blkdev.h>
83144186	15	#include <linux/freezer.h>
87598a2b	16	#include <linux/kthread.h>
45711f1a	17	#include <linux/scatterlist.h>
8e0cb8a1	18	#include <linux/dma-mapping.h>
1da177e4 LT	19
	20	#include <linux/mmc/card.h>
	21	#include <linux/mmc/host.h>
29eb7bd0	22
98ac2162	23	#include "queue.h"
29eb7bd0	24	#include "block.h"
1da177e4	25
98ccf149 PO	26	#define MMC_QUEUE_BOUNCESZ 65536
98ccf149 PO	27
1da177e4	28	/*
9c9f2d63	29	* Prepare a MMC request. This just filters out odd stuff.
1da177e4 LT	30	*/
	31	static int mmc_prep_request(struct request_queue q, struct request req)
	32	{
a8ad82cc SRT	33	struct mmc_queue *mq = q->queuedata;
a8ad82cc SRT	34
9c9f2d63	35	/*
bd788c96	36	* We only like normal block requests and discards.
9c9f2d63	37	*/
7afafc8a AH	38	if (req->cmd_type != REQ_TYPE_FS && req_op(req) != REQ_OP_DISCARD &&
7afafc8a AH	39	req_op(req) != REQ_OP_SECURE_ERASE) {
1da177e4	40	blk_dump_rq_flags(req, "MMC bad request");
9c9f2d63	41	return BLKPREP_KILL;
1da177e4 LT	42	}
1da177e4 LT	43
4e93b9a6	44	if (mq && (mmc_card_removed(mq->card) \|\| mmc_access_rpmb(mq)))
a8ad82cc SRT	45	return BLKPREP_KILL;
a8ad82cc SRT	46
9c9f2d63	47	req->cmd_flags \|= REQ_DONTPREP;
1da177e4	48
9c9f2d63	49	return BLKPREP_OK;
1da177e4 LT	50	}
	51
	52	static int mmc_queue_thread(void *d)
	53	{
	54	struct mmc_queue *mq = d;
	55	struct request_queue *q = mq->queue;
e0097cf5	56	struct mmc_context_info *cntx = &mq->card->host->context_info;
1da177e4	57
83144186	58	current->flags \|= PF_MEMALLOC;
1da177e4	59
1da177e4	60	down(&mq->thread_sem);
1da177e4 LT	61	do {
	62	struct request *req = NULL;
	63
	64	spin_lock_irq(q->queue_lock);
	65	set_current_state(TASK_INTERRUPTIBLE);
7eaceacc	66	req = blk_fetch_request(q);
e0097cf5 AH	67	mq->asleep = false;
	68	cntx->is_waiting_last_req = false;
	69	cntx->is_new_req = false;
	70	if (!req) {
	71	/*
	72	* Dispatch queue is empty so set flags for
	73	* mmc_request_fn() to wake us up.
	74	*/
	75	if (mq->mqrq_prev->req)
	76	cntx->is_waiting_last_req = true;
	77	else
	78	mq->asleep = true;
	79	}
97868a2b	80	mq->mqrq_cur->req = req;
1da177e4 LT	81	spin_unlock_irq(q->queue_lock);
1da177e4 LT	82
ee8a43a5	83	if (req \|\| mq->mqrq_prev->req) {
869c5548 AH	84	bool req_is_special = mmc_req_is_special(req);
869c5548 AH	85
ee8a43a5	86	set_current_state(TASK_RUNNING);
29eb7bd0	87	mmc_blk_issue_rq(mq, req);
a8c27c0b	88	cond_resched();
2220eedf KD	89	if (mq->flags & MMC_QUEUE_NEW_REQUEST) {
	90	mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
	91	continue; /* fetch again */
	92	}
45c5a914 SJ	93
	94	/*
	95	* Current request becomes previous request
	96	* and vice versa.
369d321e SJ	97	* In case of special requests, current request
	98	* has been finished. Do not assign it to previous
	99	* request.
45c5a914	100	*/
869c5548	101	if (req_is_special)
369d321e SJ	102	mq->mqrq_cur->req = NULL;
369d321e SJ	103
45c5a914 SJ	104	mq->mqrq_prev->brq.mrq.data = NULL;
45c5a914 SJ	105	mq->mqrq_prev->req = NULL;
7551847c	106	swap(mq->mqrq_prev, mq->mqrq_cur);
ee8a43a5	107	} else {
7b30d281 VW	108	if (kthread_should_stop()) {
7b30d281 VW	109	set_current_state(TASK_RUNNING);
1da177e4	110	break;
7b30d281	111	}
1da177e4 LT	112	up(&mq->thread_sem);
	113	schedule();
	114	down(&mq->thread_sem);
1da177e4	115	}
1da177e4	116	} while (1);
1da177e4 LT	117	up(&mq->thread_sem);
1da177e4 LT	118
1da177e4 LT	119	return 0;
	120	}
	121
	122	/*
	123	* Generic MMC request handler. This is called for any queue on a
	124	* particular host. When the host is not busy, we look for a request
	125	* on any queue on this host, and attempt to issue it. This may
	126	* not be the queue we were asked to process.
	127	*/
1b50f5f3	128	static void mmc_request_fn(struct request_queue *q)
1da177e4 LT	129	{
1da177e4 LT	130	struct mmc_queue *mq = q->queuedata;
89b4e133	131	struct request *req;
2220eedf	132	struct mmc_context_info *cntx;
89b4e133 PO	133
89b4e133 PO	134	if (!mq) {
5fa83ce2 AH	135	while ((req = blk_fetch_request(q)) != NULL) {
5fa83ce2 AH	136	req->cmd_flags \|= REQ_QUIET;
296b2f6a	137	__blk_end_request_all(req, -EIO);
5fa83ce2	138	}
89b4e133 PO	139	return;
89b4e133 PO	140	}
1da177e4	141
2220eedf	142	cntx = &mq->card->host->context_info;
e0097cf5 AH	143
	144	if (cntx->is_waiting_last_req) {
	145	cntx->is_new_req = true;
	146	wake_up_interruptible(&cntx->wait);
	147	}
	148
	149	if (mq->asleep)
87598a2b	150	wake_up_process(mq->thread);
1da177e4 LT	151	}
1da177e4 LT	152
7513cd7a	153	static struct scatterlist mmc_alloc_sg(int sg_len, int err)
97868a2b PF	154	{
	155	struct scatterlist *sg;
	156
	157	sg = kmalloc(sizeof(struct scatterlist)*sg_len, GFP_KERNEL);
	158	if (!sg)
	159	*err = -ENOMEM;
	160	else {
	161	*err = 0;
	162	sg_init_table(sg, sg_len);
	163	}
	164
	165	return sg;
	166	}
	167
e056a1b5 AH	168	static void mmc_queue_setup_discard(struct request_queue *q,
	169	struct mmc_card *card)
	170	{
	171	unsigned max_discard;
	172
	173	max_discard = mmc_calc_max_discard(card);
	174	if (!max_discard)
	175	return;
	176
	177	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
2bb4cd5c	178	blk_queue_max_discard_sectors(q, max_discard);
7194efb8	179	if (card->erased_byte == 0 && !mmc_can_discard(card))
e056a1b5 AH	180	q->limits.discard_zeroes_data = 1;
	181	q->limits.discard_granularity = card->pref_erase << 9;
	182	/* granularity must not be greater than max. discard */
	183	if (card->pref_erase > max_discard)
	184	q->limits.discard_granularity = 0;
775a9362	185	if (mmc_can_secure_erase_trim(card))
288dab8a	186	queue_flag_set_unlocked(QUEUE_FLAG_SECERASE, q);
e056a1b5 AH	187	}
e056a1b5 AH	188
c853982e AH	189	#ifdef CONFIG_MMC_BLOCK_BOUNCE
	190	static bool mmc_queue_alloc_bounce_bufs(struct mmc_queue *mq,
	191	unsigned int bouncesz)
	192	{
c5bda0ca	193	int i;
c853982e	194
c5bda0ca AH	195	for (i = 0; i < mq->qdepth; i++) {
	196	mq->mqrq[i].bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
	197	if (!mq->mqrq[i].bounce_buf)
	198	goto out_err;
c853982e AH	199	}
	200
	201	return true;
c5bda0ca AH	202
	203	out_err:
	204	while (--i >= 0) {
	205	kfree(mq->mqrq[i].bounce_buf);
	206	mq->mqrq[i].bounce_buf = NULL;
	207	}
	208	pr_warn("%s: unable to allocate bounce buffers\n",
	209	mmc_card_name(mq->card));
	210	return false;
c853982e	211	}
f2b8b522 AH	212
	213	static int mmc_queue_alloc_bounce_sgs(struct mmc_queue *mq,
	214	unsigned int bouncesz)
	215	{
c5bda0ca	216	int i, ret;
f2b8b522	217
c5bda0ca AH	218	for (i = 0; i < mq->qdepth; i++) {
	219	mq->mqrq[i].sg = mmc_alloc_sg(1, &ret);
	220	if (ret)
	221	return ret;
f2b8b522	222
c5bda0ca AH	223	mq->mqrq[i].bounce_sg = mmc_alloc_sg(bouncesz / 512, &ret);
	224	if (ret)
	225	return ret;
	226	}
f2b8b522	227
c5bda0ca	228	return 0;
f2b8b522	229	}
c853982e AH	230	#endif
c853982e AH	231
64e29e42 AH	232	static int mmc_queue_alloc_sgs(struct mmc_queue *mq, int max_segs)
64e29e42 AH	233	{
c5bda0ca	234	int i, ret;
64e29e42	235
c5bda0ca AH	236	for (i = 0; i < mq->qdepth; i++) {
	237	mq->mqrq[i].sg = mmc_alloc_sg(max_segs, &ret);
	238	if (ret)
	239	return ret;
	240	}
64e29e42	241
c5bda0ca AH	242	return 0;
c5bda0ca AH	243	}
64e29e42	244
c5bda0ca AH	245	static void mmc_queue_req_free_bufs(struct mmc_queue_req *mqrq)
	246	{
	247	kfree(mqrq->bounce_sg);
	248	mqrq->bounce_sg = NULL;
	249
	250	kfree(mqrq->sg);
	251	mqrq->sg = NULL;
	252
	253	kfree(mqrq->bounce_buf);
	254	mqrq->bounce_buf = NULL;
64e29e42 AH	255	}
64e29e42 AH	256
c09949cf AH	257	static void mmc_queue_reqs_free_bufs(struct mmc_queue *mq)
c09949cf AH	258	{
c5bda0ca AH	259	int i;
	260
	261	for (i = 0; i < mq->qdepth; i++)
	262	mmc_queue_req_free_bufs(&mq->mqrq[i]);
c09949cf AH	263	}
c09949cf AH	264
1da177e4 LT	265	/**
	266	* mmc_init_queue - initialise a queue structure.
	267	* @mq: mmc queue
	268	* @card: mmc card to attach this queue
	269	* @lock: queue lock
d09408ad	270	* @subname: partition subname
1da177e4 LT	271	*
	272	* Initialise a MMC card request queue.
	273	*/
d09408ad AH	274	int mmc_init_queue(struct mmc_queue mq, struct mmc_card card,
d09408ad AH	275	spinlock_t lock, const char subname)
1da177e4 LT	276	{
	277	struct mmc_host *host = card->host;
	278	u64 limit = BLK_BOUNCE_HIGH;
f2b8b522	279	bool bounce = false;
c5bda0ca	280	int ret = -ENOMEM;
1da177e4	281
fcaf71fd	282	if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
e83b3664	283	limit = (u64)dma_max_pfn(mmc_dev(host)) << PAGE_SHIFT;
1da177e4 LT	284
1da177e4 LT	285	mq->card = card;
1b50f5f3	286	mq->queue = blk_init_queue(mmc_request_fn, lock);
1da177e4 LT	287	if (!mq->queue)
	288	return -ENOMEM;
	289
c5bda0ca AH	290	mq->qdepth = 2;
	291	mq->mqrq = kcalloc(mq->qdepth, sizeof(struct mmc_queue_req),
	292	GFP_KERNEL);
	293	if (!mq->mqrq)
	294	goto blk_cleanup;
c09949cf AH	295	mq->mqrq_cur = &mq->mqrq[0];
c09949cf AH	296	mq->mqrq_prev = &mq->mqrq[1];
1da177e4	297	mq->queue->queuedata = mq;
1da177e4	298
98ccf149	299	blk_queue_prep_rq(mq->queue, mmc_prep_request);
8dddfe19	300	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
b277da0a	301	queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, mq->queue);
e056a1b5 AH	302	if (mmc_can_erase(card))
e056a1b5 AH	303	mmc_queue_setup_discard(mq->queue, card);
98ccf149 PO	304
98ccf149 PO	305	#ifdef CONFIG_MMC_BLOCK_BOUNCE
a36274e0	306	if (host->max_segs == 1) {
aafabfab PO	307	unsigned int bouncesz;
aafabfab PO	308
98ccf149 PO	309	bouncesz = MMC_QUEUE_BOUNCESZ;
	310
	311	if (bouncesz > host->max_req_size)
	312	bouncesz = host->max_req_size;
	313	if (bouncesz > host->max_seg_size)
	314	bouncesz = host->max_seg_size;
f3eb0aaa PO	315	if (bouncesz > (host->max_blk_count * 512))
	316	bouncesz = host->max_blk_count * 512;
	317
c853982e AH	318	if (bouncesz > 512 &&
c853982e AH	319	mmc_queue_alloc_bounce_bufs(mq, bouncesz)) {
2ff1fa67	320	blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_ANY);
086fa5ff	321	blk_queue_max_hw_sectors(mq->queue, bouncesz / 512);
8a78362c	322	blk_queue_max_segments(mq->queue, bouncesz / 512);
98ccf149 PO	323	blk_queue_max_segment_size(mq->queue, bouncesz);
98ccf149 PO	324
f2b8b522	325	ret = mmc_queue_alloc_bounce_sgs(mq, bouncesz);
04296b7b PF	326	if (ret)
04296b7b PF	327	goto cleanup_queue;
f2b8b522	328	bounce = true;
98ccf149 PO	329	}
	330	}
	331	#endif
	332
f2b8b522	333	if (!bounce) {
98ccf149	334	blk_queue_bounce_limit(mq->queue, limit);
086fa5ff	335	blk_queue_max_hw_sectors(mq->queue,
f3eb0aaa	336	min(host->max_blk_count, host->max_req_size / 512));
a36274e0	337	blk_queue_max_segments(mq->queue, host->max_segs);
98ccf149 PO	338	blk_queue_max_segment_size(mq->queue, host->max_seg_size);
98ccf149 PO	339
64e29e42	340	ret = mmc_queue_alloc_sgs(mq, host->max_segs);
04296b7b PF	341	if (ret)
04296b7b PF	342	goto cleanup_queue;
1da177e4 LT	343	}
1da177e4 LT	344
632cf92a	345	sema_init(&mq->thread_sem, 1);
1da177e4	346
d09408ad AH	347	mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd/%d%s",
d09408ad AH	348	host->index, subname ? subname : "");
de528fa3	349
87598a2b CH	350	if (IS_ERR(mq->thread)) {
87598a2b CH	351	ret = PTR_ERR(mq->thread);
c09949cf	352	goto cleanup_queue;
1da177e4 LT	353	}
1da177e4 LT	354
87598a2b	355	return 0;
97868a2b	356
aafabfab	357	cleanup_queue:
c09949cf	358	mmc_queue_reqs_free_bufs(mq);
c5bda0ca AH	359	kfree(mq->mqrq);
	360	mq->mqrq = NULL;
	361	blk_cleanup:
1da177e4	362	blk_cleanup_queue(mq->queue);
1da177e4 LT	363	return ret;
1da177e4 LT	364	}
1da177e4 LT	365
	366	void mmc_cleanup_queue(struct mmc_queue *mq)
	367	{
165125e1	368	struct request_queue *q = mq->queue;
89b4e133 PO	369	unsigned long flags;
89b4e133 PO	370
d2b46f66 PO	371	/* Make sure the queue isn't suspended, as that will deadlock */
	372	mmc_queue_resume(mq);
	373
89b4e133	374	/* Then terminate our worker thread */
87598a2b	375	kthread_stop(mq->thread);
1da177e4	376
5fa83ce2 AH	377	/* Empty the queue */
	378	spin_lock_irqsave(q->queue_lock, flags);
	379	q->queuedata = NULL;
	380	blk_start_queue(q);
	381	spin_unlock_irqrestore(q->queue_lock, flags);
	382
c09949cf	383	mmc_queue_reqs_free_bufs(mq);
c5bda0ca AH	384	kfree(mq->mqrq);
c5bda0ca AH	385	mq->mqrq = NULL;
04296b7b	386
1da177e4 LT	387	mq->card = NULL;
	388	}
	389	EXPORT_SYMBOL(mmc_cleanup_queue);
	390
	391	/**
	392	* mmc_queue_suspend - suspend a MMC request queue
	393	* @mq: MMC queue to suspend
	394	*
	395	* Stop the block request queue, and wait for our thread to
	396	* complete any outstanding requests. This ensures that we
	397	* won't suspend while a request is being processed.
	398	*/
	399	void mmc_queue_suspend(struct mmc_queue *mq)
	400	{
165125e1	401	struct request_queue *q = mq->queue;
1da177e4 LT	402	unsigned long flags;
	403
	404	if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
	405	mq->flags \|= MMC_QUEUE_SUSPENDED;
	406
	407	spin_lock_irqsave(q->queue_lock, flags);
	408	blk_stop_queue(q);
	409	spin_unlock_irqrestore(q->queue_lock, flags);
	410
	411	down(&mq->thread_sem);
	412	}
	413	}
1da177e4 LT	414
	415	/**
	416	* mmc_queue_resume - resume a previously suspended MMC request queue
	417	* @mq: MMC queue to resume
	418	*/
	419	void mmc_queue_resume(struct mmc_queue *mq)
	420	{
165125e1	421	struct request_queue *q = mq->queue;
1da177e4 LT	422	unsigned long flags;
	423
	424	if (mq->flags & MMC_QUEUE_SUSPENDED) {
	425	mq->flags &= ~MMC_QUEUE_SUSPENDED;
	426
	427	up(&mq->thread_sem);
	428
	429	spin_lock_irqsave(q->queue_lock, flags);
	430	blk_start_queue(q);
	431	spin_unlock_irqrestore(q->queue_lock, flags);
	432	}
	433	}
98ac2162	434
2ff1fa67 PO	435	/*
	436	* Prepare the sg list(s) to be handed of to the host driver
	437	*/
97868a2b	438	unsigned int mmc_queue_map_sg(struct mmc_queue mq, struct mmc_queue_req mqrq)
98ccf149 PO	439	{
98ccf149 PO	440	unsigned int sg_len;
2ff1fa67 PO	441	size_t buflen;
	442	struct scatterlist *sg;
	443	int i;
98ccf149	444
03d640ae LW	445	if (!mqrq->bounce_buf)
03d640ae LW	446	return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);
98ccf149	447
97868a2b	448	BUG_ON(!mqrq->bounce_sg);
98ccf149	449
03d640ae	450	sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg);
98ccf149	451
97868a2b	452	mqrq->bounce_sg_len = sg_len;
98ccf149	453
2ff1fa67	454	buflen = 0;
97868a2b	455	for_each_sg(mqrq->bounce_sg, sg, sg_len, i)
2ff1fa67	456	buflen += sg->length;
98ccf149	457
97868a2b	458	sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen);
98ccf149 PO	459
	460	return 1;
	461	}
	462
2ff1fa67 PO	463	/*
	464	* If writing, bounce the data to the buffer before the request
	465	* is sent to the host driver
	466	*/
97868a2b	467	void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq)
98ccf149	468	{
97868a2b	469	if (!mqrq->bounce_buf)
98ccf149 PO	470	return;
98ccf149 PO	471
97868a2b	472	if (rq_data_dir(mqrq->req) != WRITE)
98ccf149 PO	473	return;
98ccf149 PO	474
97868a2b PF	475	sg_copy_to_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
97868a2b PF	476	mqrq->bounce_buf, mqrq->sg[0].length);
98ccf149 PO	477	}
98ccf149 PO	478
2ff1fa67 PO	479	/*
	480	* If reading, bounce the data from the buffer after the request
	481	* has been handled by the host driver
	482	*/
97868a2b	483	void mmc_queue_bounce_post(struct mmc_queue_req *mqrq)
98ccf149	484	{
97868a2b	485	if (!mqrq->bounce_buf)
98ccf149 PO	486	return;
98ccf149 PO	487
97868a2b	488	if (rq_data_dir(mqrq->req) != READ)
98ccf149 PO	489	return;
98ccf149 PO	490
97868a2b PF	491	sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
97868a2b PF	492	mqrq->bounce_buf, mqrq->sg[0].length);
98ccf149	493	}