1 files changed, 141 insertions, 76 deletions

diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index 6413afa318d..45fb362e3f0 100644
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -52,14 +52,18 @@ static int mmc_queue_thread(void *d)
 	down(&mq->thread_sem);
 	do {
 		struct request *req = NULL;
+		struct mmc_queue_req *tmp;
 
 		spin_lock_irq(q->queue_lock);
 		set_current_state(TASK_INTERRUPTIBLE);
 		req = blk_fetch_request(q);
-		mq->req = req;
+		mq->mqrq_cur->req = req;
 		spin_unlock_irq(q->queue_lock);
 
-		if (!req) {
+		if (req || mq->mqrq_prev->req) {
+			set_current_state(TASK_RUNNING);
+			mq->issue_fn(mq, req);
+		} else {
 			if (kthread_should_stop()) {
 				set_current_state(TASK_RUNNING);
 				break;
@@ -67,11 +71,14 @@ static int mmc_queue_thread(void *d)
 			up(&mq->thread_sem);
 			schedule();
 			down(&mq->thread_sem);
-			continue;
 		}
-		set_current_state(TASK_RUNNING);
 
-		mq->issue_fn(mq, req);
+		/* Current request becomes previous request and vice versa. */
+		mq->mqrq_prev->brq.mrq.data = NULL;
+		mq->mqrq_prev->req = NULL;
+		tmp = mq->mqrq_prev;
+		mq->mqrq_prev = mq->mqrq_cur;
+		mq->mqrq_cur = tmp;
 	} while (1);
 	up(&mq->thread_sem);
 
@@ -97,10 +104,46 @@ static void mmc_request(struct request_queue *q)
 		return;
 	}
 
-	if (!mq->req)
+	if (!mq->mqrq_cur->req && !mq->mqrq_prev->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
@@ -116,6 +159,8 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
 	struct mmc_host *host = card->host;
 	u64 limit = BLK_BOUNCE_HIGH;
 	int ret;
+	struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
+	struct mmc_queue_req *mqrq_prev = &mq->mqrq[1];
 
 	if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
 		limit = *mmc_dev(host)->dma_mask;
@@ -125,21 +170,16 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
 	if (!mq->queue)
 		return -ENOMEM;
 
+	memset(&mq->mqrq_cur, 0, sizeof(mq->mqrq_cur));
+	memset(&mq->mqrq_prev, 0, sizeof(mq->mqrq_prev));
+	mq->mqrq_cur = mqrq_cur;
+	mq->mqrq_prev = mqrq_prev;
 	mq->queue->queuedata = mq;
-	mq->req = NULL;
 
 	blk_queue_prep_rq(mq->queue, mmc_prep_request);
 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
-	if (mmc_can_erase(card)) {
-		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mq->queue);
-		mq->queue->limits.max_discard_sectors = UINT_MAX;
-		if (card->erased_byte == 0)
-			mq->queue->limits.discard_zeroes_data = 1;
-		mq->queue->limits.discard_granularity = card->pref_erase << 9;
-		if (mmc_can_secure_erase_trim(card))
-			queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD,
-						mq->queue);
-	}
+	if (mmc_can_erase(card))
+		mmc_queue_setup_discard(mq->queue, card);
 
 #ifdef CONFIG_MMC_BLOCK_BOUNCE
 	if (host->max_segs == 1) {
@@ -155,53 +195,64 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
 			bouncesz = host->max_blk_count * 512;
 
 		if (bouncesz > 512) {
-			mq->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
-			if (!mq->bounce_buf) {
+			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));
+			}
+			mqrq_prev->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
+			if (!mqrq_prev->bounce_buf) {
 				printk(KERN_WARNING "%s: unable to "
-					"allocate bounce buffer\n",
+					"allocate bounce prev buffer\n",
 					mmc_card_name(card));
+				kfree(mqrq_cur->bounce_buf);
+				mqrq_cur->bounce_buf = NULL;
 			}
 		}
 
-		if (mq->bounce_buf) {
+		if (mqrq_cur->bounce_buf && mqrq_prev->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);
 
-			mq->sg = kmalloc(sizeof(struct scatterlist),
-				GFP_KERNEL);
-			if (!mq->sg) {
-				ret = -ENOMEM;
+			mqrq_cur->sg = mmc_alloc_sg(1, &ret);
+			if (ret)
 				goto cleanup_queue;
-			}
-			sg_init_table(mq->sg, 1);
 
-			mq->bounce_sg = kmalloc(sizeof(struct scatterlist) *
-				bouncesz / 512, GFP_KERNEL);
-			if (!mq->bounce_sg) {
-				ret = -ENOMEM;
+			mqrq_cur->bounce_sg =
+				mmc_alloc_sg(bouncesz / 512, &ret);
+			if (ret)
+				goto cleanup_queue;
+
+			mqrq_prev->sg = mmc_alloc_sg(1, &ret);
+			if (ret)
+				goto cleanup_queue;
+
+			mqrq_prev->bounce_sg =
+				mmc_alloc_sg(bouncesz / 512, &ret);
+			if (ret)
 				goto cleanup_queue;
-			}
-			sg_init_table(mq->bounce_sg, bouncesz / 512);
 		}
 	}
 #endif
 
-	if (!mq->bounce_buf) {
+	if (!mqrq_cur->bounce_buf && !mqrq_prev->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);
 
-		mq->sg = kmalloc(sizeof(struct scatterlist) *
-			host->max_segs, GFP_KERNEL);
-		if (!mq->sg) {
-			ret = -ENOMEM;
+		mqrq_cur->sg = mmc_alloc_sg(host->max_segs, &ret);
+		if (ret)
+			goto cleanup_queue;
+
+
+		mqrq_prev->sg = mmc_alloc_sg(host->max_segs, &ret);
+		if (ret)
 			goto cleanup_queue;
-		}
-		sg_init_table(mq->sg, host->max_segs);
 	}
 
 	sema_init(&mq->thread_sem, 1);
@@ -216,16 +267,22 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
 
 	return 0;
  free_bounce_sg:
- 	if (mq->bounce_sg)
- 		kfree(mq->bounce_sg);
- 	mq->bounce_sg = NULL;
+	kfree(mqrq_cur->bounce_sg);
+	mqrq_cur->bounce_sg = NULL;
+	kfree(mqrq_prev->bounce_sg);
+	mqrq_prev->bounce_sg = NULL;
+
  cleanup_queue:
- 	if (mq->sg)
-		kfree(mq->sg);
-	mq->sg = NULL;
-	if (mq->bounce_buf)
-		kfree(mq->bounce_buf);
-	mq->bounce_buf = NULL;
+	kfree(mqrq_cur->sg);
+	mqrq_cur->sg = NULL;
+	kfree(mqrq_cur->bounce_buf);
+	mqrq_cur->bounce_buf = NULL;
+
+	kfree(mqrq_prev->sg);
+	mqrq_prev->sg = NULL;
+	kfree(mqrq_prev->bounce_buf);
+	mqrq_prev->bounce_buf = NULL;
+
 	blk_cleanup_queue(mq->queue);
 	return ret;
 }
@@ -234,6 +291,8 @@ 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;
+	struct mmc_queue_req *mqrq_prev = mq->mqrq_prev;
 
 	/* Make sure the queue isn't suspended, as that will deadlock */
 	mmc_queue_resume(mq);
@@ -247,16 +306,23 @@ void mmc_cleanup_queue(struct mmc_queue *mq)
 	blk_start_queue(q);
 	spin_unlock_irqrestore(q->queue_lock, flags);
 
- 	if (mq->bounce_sg)
- 		kfree(mq->bounce_sg);
- 	mq->bounce_sg = NULL;
+	kfree(mqrq_cur->bounce_sg);
+	mqrq_cur->bounce_sg = NULL;
 
-	kfree(mq->sg);
-	mq->sg = NULL;
+	kfree(mqrq_cur->sg);
+	mqrq_cur->sg = NULL;
 
-	if (mq->bounce_buf)
-		kfree(mq->bounce_buf);
-	mq->bounce_buf = NULL;
+	kfree(mqrq_cur->bounce_buf);
+	mqrq_cur->bounce_buf = NULL;
+
+	kfree(mqrq_prev->bounce_sg);
+	mqrq_prev->bounce_sg = NULL;
+
+	kfree(mqrq_prev->sg);
+	mqrq_prev->sg = NULL;
+
+	kfree(mqrq_prev->bounce_buf);
+	mqrq_prev->bounce_buf = NULL;
 
 	mq->card = NULL;
 }
@@ -309,27 +375,27 @@ void mmc_queue_resume(struct mmc_queue *mq)
 /*
  * Prepare the sg list(s) to be handed of to the host driver
  */
-unsigned int mmc_queue_map_sg(struct mmc_queue *mq)
+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 (!mq->bounce_buf)
-		return blk_rq_map_sg(mq->queue, mq->req, mq->sg);
+	if (!mqrq->bounce_buf)
+		return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);
 
-	BUG_ON(!mq->bounce_sg);
+	BUG_ON(!mqrq->bounce_sg);
 
-	sg_len = blk_rq_map_sg(mq->queue, mq->req, mq->bounce_sg);
+	sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg);
 
-	mq->bounce_sg_len = sg_len;
+	mqrq->bounce_sg_len = sg_len;
 
 	buflen = 0;
-	for_each_sg(mq->bounce_sg, sg, sg_len, i)
+	for_each_sg(mqrq->bounce_sg, sg, sg_len, i)
 		buflen += sg->length;
 
-	sg_init_one(mq->sg, mq->bounce_buf, buflen);
+	sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen);
 
 	return 1;
 }
@@ -338,31 +404,30 @@ unsigned int mmc_queue_map_sg(struct mmc_queue *mq)
  * 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 *mq)
+void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq)
 {
-	if (!mq->bounce_buf)
+	if (!mqrq->bounce_buf)
 		return;
 
-	if (rq_data_dir(mq->req) != WRITE)
+	if (rq_data_dir(mqrq->req) != WRITE)
 		return;
 
-	sg_copy_to_buffer(mq->bounce_sg, mq->bounce_sg_len,
-		mq->bounce_buf, mq->sg[0].length);
+	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 *mq)
+void mmc_queue_bounce_post(struct mmc_queue_req *mqrq)
 {
-	if (!mq->bounce_buf)
+	if (!mqrq->bounce_buf)
 		return;
 
-	if (rq_data_dir(mq->req) != READ)
+	if (rq_data_dir(mqrq->req) != READ)
 		return;
 
-	sg_copy_from_buffer(mq->bounce_sg, mq->bounce_sg_len,
-		mq->bounce_buf, mq->sg[0].length);
+	sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
+		mqrq->bounce_buf, mqrq->sg[0].length);
 }
-