[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/mmc/card.h>
#include <linux/mmc/host.h>
#include "queue.h"

#define MMC_QUEUE_BOUNCESZ	65536

#define MMC_QUEUE_SUSPENDED	(1 << 0)

/*
 * Prepare a MMC request. This just filters out odd stuff.
 */
static int mmc_prep_request(struct request_queue *q, struct request *req)
{
	/*
	 * We only like normal block requests and discards.
	 */
	if (req->cmd_type != REQ_TYPE_FS && !(req->cmd_flags & REQ_DISCARD)) {
		blk_dump_rq_flags(req, "MMC bad request");
		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;

	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->mqrq_cur->req = req;
		spin_unlock_irq(q->queue_lock);

		if (!req) {
			if (kthread_should_stop()) {
				set_current_state(TASK_RUNNING);
				break;
			}
			up(&mq->thread_sem);
			schedule();
			down(&mq->thread_sem);
			continue;
		}
		set_current_state(TASK_RUNNING);

		mq->issue_fn(mq, req);
	} 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(struct request_queue *q)
{
	struct mmc_queue *mq = q->queuedata;
	struct request *req;

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

	if (!mq->mqrq_cur->req)
		wake_up_process(mq->thread);
}

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);
	q->limits.max_discard_sectors = max_discard;
	if (card->erased_byte == 0)
		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_SECDISCARD, q);
}

/**
 * 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;
	int ret;
	struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];

	if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
		limit = *mmc_dev(host)->dma_mask;

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

	memset(&mq->mqrq_cur, 0, sizeof(mq->mqrq_cur));
	mq->mqrq_cur = mqrq_cur;
	mq->queue->queuedata = mq;

	blk_queue_prep_rq(mq->queue, mmc_prep_request);
	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, 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) {
			mqrq_cur->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
			if (!mqrq_cur->bounce_buf) {
				printk(KERN_WARNING "%s: unable to "
					"allocate bounce cur buffer\n",
					mmc_card_name(card));
			}
		}

		if (mqrq_cur->bounce_buf) {
			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);

			mqrq_cur->sg = mmc_alloc_sg(1, &ret);
			if (ret)
				goto cleanup_queue;

			mqrq_cur->bounce_sg =
				mmc_alloc_sg(bouncesz / 512, &ret);
			if (ret)
				goto cleanup_queue;

		}
	}
#endif

	if (!mqrq_cur->bounce_buf) {
		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);

		mqrq_cur->sg = mmc_alloc_sg(host->max_segs, &ret);
		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 free_bounce_sg;
	}

	return 0;
 free_bounce_sg:
	kfree(mqrq_cur->bounce_sg);
	mqrq_cur->bounce_sg = NULL;

 cleanup_queue:
	kfree(mqrq_cur->sg);
	mqrq_cur->sg = NULL;
	kfree(mqrq_cur->bounce_buf);
	mqrq_cur->bounce_buf = NULL;

	blk_cleanup_queue(mq->queue);
	return ret;
}

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

	/* 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);

	kfree(mqrq_cur->bounce_sg);
	mqrq_cur->bounce_sg = NULL;

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

	kfree(mqrq_cur->bounce_buf);
	mqrq_cur->bounce_buf = 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>
1da177e4 LT	18
	19	#include <linux/mmc/card.h>
	20	#include <linux/mmc/host.h>
98ac2162	21	#include "queue.h"
1da177e4	22
98ccf149 PO	23	#define MMC_QUEUE_BOUNCESZ 65536
98ccf149 PO	24
87598a2b	25	#define MMC_QUEUE_SUSPENDED (1 << 0)
1da177e4 LT	26
1da177e4 LT	27	/*
9c9f2d63	28	* Prepare a MMC request. This just filters out odd stuff.
1da177e4 LT	29	*/
	30	static int mmc_prep_request(struct request_queue q, struct request req)
	31	{
9c9f2d63	32	/*
bd788c96	33	* We only like normal block requests and discards.
9c9f2d63	34	*/
bd788c96	35	if (req->cmd_type != REQ_TYPE_FS && !(req->cmd_flags & REQ_DISCARD)) {
1da177e4	36	blk_dump_rq_flags(req, "MMC bad request");
9c9f2d63	37	return BLKPREP_KILL;
1da177e4 LT	38	}
1da177e4 LT	39
9c9f2d63	40	req->cmd_flags \|= REQ_DONTPREP;
1da177e4	41
9c9f2d63	42	return BLKPREP_OK;
1da177e4 LT	43	}
	44
	45	static int mmc_queue_thread(void *d)
	46	{
	47	struct mmc_queue *mq = d;
	48	struct request_queue *q = mq->queue;
1da177e4	49
83144186	50	current->flags \|= PF_MEMALLOC;
1da177e4	51
1da177e4	52	down(&mq->thread_sem);
1da177e4 LT	53	do {
	54	struct request *req = NULL;
	55
	56	spin_lock_irq(q->queue_lock);
	57	set_current_state(TASK_INTERRUPTIBLE);
7eaceacc	58	req = blk_fetch_request(q);
97868a2b	59	mq->mqrq_cur->req = req;
1da177e4 LT	60	spin_unlock_irq(q->queue_lock);
	61
	62	if (!req) {
7b30d281 VW	63	if (kthread_should_stop()) {
7b30d281 VW	64	set_current_state(TASK_RUNNING);
1da177e4	65	break;
7b30d281	66	}
1da177e4 LT	67	up(&mq->thread_sem);
	68	schedule();
	69	down(&mq->thread_sem);
	70	continue;
	71	}
	72	set_current_state(TASK_RUNNING);
	73
	74	mq->issue_fn(mq, req);
	75	} while (1);
1da177e4 LT	76	up(&mq->thread_sem);
1da177e4 LT	77
1da177e4 LT	78	return 0;
	79	}
	80
	81	/*
	82	* Generic MMC request handler. This is called for any queue on a
	83	* particular host. When the host is not busy, we look for a request
	84	* on any queue on this host, and attempt to issue it. This may
	85	* not be the queue we were asked to process.
	86	*/
165125e1	87	static void mmc_request(struct request_queue *q)
1da177e4 LT	88	{
1da177e4 LT	89	struct mmc_queue *mq = q->queuedata;
89b4e133	90	struct request *req;
89b4e133 PO	91
89b4e133 PO	92	if (!mq) {
5fa83ce2 AH	93	while ((req = blk_fetch_request(q)) != NULL) {
5fa83ce2 AH	94	req->cmd_flags \|= REQ_QUIET;
296b2f6a	95	__blk_end_request_all(req, -EIO);
5fa83ce2	96	}
89b4e133 PO	97	return;
89b4e133 PO	98	}
1da177e4	99
97868a2b	100	if (!mq->mqrq_cur->req)
87598a2b	101	wake_up_process(mq->thread);
1da177e4 LT	102	}
1da177e4 LT	103
97868a2b PF	104	struct scatterlist mmc_alloc_sg(int sg_len, int err)
	105	{
	106	struct scatterlist *sg;
	107
	108	sg = kmalloc(sizeof(struct scatterlist)*sg_len, GFP_KERNEL);
	109	if (!sg)
	110	*err = -ENOMEM;
	111	else {
	112	*err = 0;
	113	sg_init_table(sg, sg_len);
	114	}
	115
	116	return sg;
	117	}
	118
e056a1b5 AH	119	static void mmc_queue_setup_discard(struct request_queue *q,
	120	struct mmc_card *card)
	121	{
	122	unsigned max_discard;
	123
	124	max_discard = mmc_calc_max_discard(card);
	125	if (!max_discard)
	126	return;
	127
	128	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
	129	q->limits.max_discard_sectors = max_discard;
	130	if (card->erased_byte == 0)
	131	q->limits.discard_zeroes_data = 1;
	132	q->limits.discard_granularity = card->pref_erase << 9;
	133	/* granularity must not be greater than max. discard */
	134	if (card->pref_erase > max_discard)
	135	q->limits.discard_granularity = 0;
	136	if (mmc_can_secure_erase_trim(card))
	137	queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD, q);
	138	}
	139
1da177e4 LT	140	/**
	141	* mmc_init_queue - initialise a queue structure.
	142	* @mq: mmc queue
	143	* @card: mmc card to attach this queue
	144	* @lock: queue lock
d09408ad	145	* @subname: partition subname
1da177e4 LT	146	*
	147	* Initialise a MMC card request queue.
	148	*/
d09408ad AH	149	int mmc_init_queue(struct mmc_queue mq, struct mmc_card card,
d09408ad AH	150	spinlock_t lock, const char subname)
1da177e4 LT	151	{
	152	struct mmc_host *host = card->host;
	153	u64 limit = BLK_BOUNCE_HIGH;
	154	int ret;
97868a2b	155	struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
1da177e4	156
fcaf71fd GKH	157	if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
fcaf71fd GKH	158	limit = *mmc_dev(host)->dma_mask;
1da177e4 LT	159
	160	mq->card = card;
	161	mq->queue = blk_init_queue(mmc_request, lock);
	162	if (!mq->queue)
	163	return -ENOMEM;
	164
97868a2b PF	165	memset(&mq->mqrq_cur, 0, sizeof(mq->mqrq_cur));
97868a2b PF	166	mq->mqrq_cur = mqrq_cur;
1da177e4	167	mq->queue->queuedata = mq;
1da177e4	168
98ccf149	169	blk_queue_prep_rq(mq->queue, mmc_prep_request);
8dddfe19	170	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
e056a1b5 AH	171	if (mmc_can_erase(card))
e056a1b5 AH	172	mmc_queue_setup_discard(mq->queue, card);
98ccf149 PO	173
98ccf149 PO	174	#ifdef CONFIG_MMC_BLOCK_BOUNCE
a36274e0	175	if (host->max_segs == 1) {
aafabfab PO	176	unsigned int bouncesz;
aafabfab PO	177
98ccf149 PO	178	bouncesz = MMC_QUEUE_BOUNCESZ;
	179
	180	if (bouncesz > host->max_req_size)
	181	bouncesz = host->max_req_size;
	182	if (bouncesz > host->max_seg_size)
	183	bouncesz = host->max_seg_size;
f3eb0aaa PO	184	if (bouncesz > (host->max_blk_count * 512))
	185	bouncesz = host->max_blk_count * 512;
	186
	187	if (bouncesz > 512) {
97868a2b PF	188	mqrq_cur->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
97868a2b PF	189	if (!mqrq_cur->bounce_buf) {
f3eb0aaa	190	printk(KERN_WARNING "%s: unable to "
97868a2b	191	"allocate bounce cur buffer\n",
f3eb0aaa PO	192	mmc_card_name(card));
	193	}
	194	}
98ccf149	195
97868a2b	196	if (mqrq_cur->bounce_buf) {
2ff1fa67	197	blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_ANY);
086fa5ff	198	blk_queue_max_hw_sectors(mq->queue, bouncesz / 512);
8a78362c	199	blk_queue_max_segments(mq->queue, bouncesz / 512);
98ccf149 PO	200	blk_queue_max_segment_size(mq->queue, bouncesz);
98ccf149 PO	201
97868a2b PF	202	mqrq_cur->sg = mmc_alloc_sg(1, &ret);
97868a2b PF	203	if (ret)
aafabfab	204	goto cleanup_queue;
98ccf149	205
97868a2b PF	206	mqrq_cur->bounce_sg =
	207	mmc_alloc_sg(bouncesz / 512, &ret);
	208	if (ret)
aafabfab	209	goto cleanup_queue;
97868a2b	210
98ccf149 PO	211	}
	212	}
	213	#endif
	214
97868a2b	215	if (!mqrq_cur->bounce_buf) {
98ccf149	216	blk_queue_bounce_limit(mq->queue, limit);
086fa5ff	217	blk_queue_max_hw_sectors(mq->queue,
f3eb0aaa	218	min(host->max_blk_count, host->max_req_size / 512));
a36274e0	219	blk_queue_max_segments(mq->queue, host->max_segs);
98ccf149 PO	220	blk_queue_max_segment_size(mq->queue, host->max_seg_size);
98ccf149 PO	221
97868a2b PF	222	mqrq_cur->sg = mmc_alloc_sg(host->max_segs, &ret);
97868a2b PF	223	if (ret)
98ccf149	224	goto cleanup_queue;
97868a2b	225
1da177e4 LT	226	}
1da177e4 LT	227
632cf92a	228	sema_init(&mq->thread_sem, 1);
1da177e4	229
d09408ad AH	230	mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd/%d%s",
d09408ad AH	231	host->index, subname ? subname : "");
de528fa3	232
87598a2b CH	233	if (IS_ERR(mq->thread)) {
87598a2b CH	234	ret = PTR_ERR(mq->thread);
98ccf149	235	goto free_bounce_sg;
1da177e4 LT	236	}
1da177e4 LT	237
87598a2b	238	return 0;
98ccf149	239	free_bounce_sg:
97868a2b PF	240	kfree(mqrq_cur->bounce_sg);
	241	mqrq_cur->bounce_sg = NULL;
	242
aafabfab	243	cleanup_queue:
97868a2b PF	244	kfree(mqrq_cur->sg);
	245	mqrq_cur->sg = NULL;
	246	kfree(mqrq_cur->bounce_buf);
	247	mqrq_cur->bounce_buf = NULL;
	248
1da177e4	249	blk_cleanup_queue(mq->queue);
1da177e4 LT	250	return ret;
1da177e4 LT	251	}
1da177e4 LT	252
	253	void mmc_cleanup_queue(struct mmc_queue *mq)
	254	{
165125e1	255	struct request_queue *q = mq->queue;
89b4e133	256	unsigned long flags;
97868a2b	257	struct mmc_queue_req *mqrq_cur = mq->mqrq_cur;
89b4e133	258
d2b46f66 PO	259	/* Make sure the queue isn't suspended, as that will deadlock */
	260	mmc_queue_resume(mq);
	261
89b4e133	262	/* Then terminate our worker thread */
87598a2b	263	kthread_stop(mq->thread);
1da177e4	264
5fa83ce2 AH	265	/* Empty the queue */
	266	spin_lock_irqsave(q->queue_lock, flags);
	267	q->queuedata = NULL;
	268	blk_start_queue(q);
	269	spin_unlock_irqrestore(q->queue_lock, flags);
	270
97868a2b PF	271	kfree(mqrq_cur->bounce_sg);
97868a2b PF	272	mqrq_cur->bounce_sg = NULL;
98ccf149	273
97868a2b PF	274	kfree(mqrq_cur->sg);
97868a2b PF	275	mqrq_cur->sg = NULL;
1da177e4	276
97868a2b PF	277	kfree(mqrq_cur->bounce_buf);
97868a2b PF	278	mqrq_cur->bounce_buf = NULL;
98ccf149	279
1da177e4 LT	280	mq->card = NULL;
	281	}
	282	EXPORT_SYMBOL(mmc_cleanup_queue);
	283
	284	/**
	285	* mmc_queue_suspend - suspend a MMC request queue
	286	* @mq: MMC queue to suspend
	287	*
	288	* Stop the block request queue, and wait for our thread to
	289	* complete any outstanding requests. This ensures that we
	290	* won't suspend while a request is being processed.
	291	*/
	292	void mmc_queue_suspend(struct mmc_queue *mq)
	293	{
165125e1	294	struct request_queue *q = mq->queue;
1da177e4 LT	295	unsigned long flags;
	296
	297	if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
	298	mq->flags \|= MMC_QUEUE_SUSPENDED;
	299
	300	spin_lock_irqsave(q->queue_lock, flags);
	301	blk_stop_queue(q);
	302	spin_unlock_irqrestore(q->queue_lock, flags);
	303
	304	down(&mq->thread_sem);
	305	}
	306	}
1da177e4 LT	307
	308	/**
	309	* mmc_queue_resume - resume a previously suspended MMC request queue
	310	* @mq: MMC queue to resume
	311	*/
	312	void mmc_queue_resume(struct mmc_queue *mq)
	313	{
165125e1	314	struct request_queue *q = mq->queue;
1da177e4 LT	315	unsigned long flags;
	316
	317	if (mq->flags & MMC_QUEUE_SUSPENDED) {
	318	mq->flags &= ~MMC_QUEUE_SUSPENDED;
	319
	320	up(&mq->thread_sem);
	321
	322	spin_lock_irqsave(q->queue_lock, flags);
	323	blk_start_queue(q);
	324	spin_unlock_irqrestore(q->queue_lock, flags);
	325	}
	326	}
98ac2162	327
2ff1fa67 PO	328	/*
	329	* Prepare the sg list(s) to be handed of to the host driver
	330	*/
97868a2b	331	unsigned int mmc_queue_map_sg(struct mmc_queue mq, struct mmc_queue_req mqrq)
98ccf149 PO	332	{
98ccf149 PO	333	unsigned int sg_len;
2ff1fa67 PO	334	size_t buflen;
	335	struct scatterlist *sg;
	336	int i;
98ccf149	337
97868a2b PF	338	if (!mqrq->bounce_buf)
97868a2b PF	339	return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);
98ccf149	340
97868a2b	341	BUG_ON(!mqrq->bounce_sg);
98ccf149	342
97868a2b	343	sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg);
98ccf149	344
97868a2b	345	mqrq->bounce_sg_len = sg_len;
98ccf149	346
2ff1fa67	347	buflen = 0;
97868a2b	348	for_each_sg(mqrq->bounce_sg, sg, sg_len, i)
2ff1fa67	349	buflen += sg->length;
98ccf149	350
97868a2b	351	sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen);
98ccf149 PO	352
	353	return 1;
	354	}
	355
2ff1fa67 PO	356	/*
	357	* If writing, bounce the data to the buffer before the request
	358	* is sent to the host driver
	359	*/
97868a2b	360	void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq)
98ccf149	361	{
97868a2b	362	if (!mqrq->bounce_buf)
98ccf149 PO	363	return;
98ccf149 PO	364
97868a2b	365	if (rq_data_dir(mqrq->req) != WRITE)
98ccf149 PO	366	return;
98ccf149 PO	367
97868a2b PF	368	sg_copy_to_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
97868a2b PF	369	mqrq->bounce_buf, mqrq->sg[0].length);
98ccf149 PO	370	}
98ccf149 PO	371
2ff1fa67 PO	372	/*
	373	* If reading, bounce the data from the buffer after the request
	374	* has been handled by the host driver
	375	*/
97868a2b	376	void mmc_queue_bounce_post(struct mmc_queue_req *mqrq)
98ccf149	377	{
97868a2b	378	if (!mqrq->bounce_buf)
98ccf149 PO	379	return;
98ccf149 PO	380
97868a2b	381	if (rq_data_dir(mqrq->req) != READ)
98ccf149 PO	382	return;
98ccf149 PO	383
97868a2b PF	384	sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
97868a2b PF	385	mqrq->bounce_buf, mqrq->sg[0].length);
98ccf149	386	}