1 files changed, 30 insertions, 129 deletions

diff --git a/block/blk-flush.c b/block/blk-flush.c
index 331e627301e..3cb5e9e7108 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -130,20 +130,21 @@ static void blk_flush_restore_request(struct request *rq)
 	blk_clear_rq_complete(rq);
 }
 
-static void mq_flush_data_run(struct work_struct *work)
+static bool blk_flush_queue_rq(struct request *rq, bool add_front)
 {
-	struct request *rq;
+	if (rq->q->mq_ops) {
+		struct request_queue *q = rq->q;
 
-	rq = container_of(work, struct request, mq_flush_data);
-
-	memset(&rq->csd, 0, sizeof(rq->csd));
-	blk_mq_run_request(rq, true, false);
-}
-
-static void blk_mq_flush_data_insert(struct request *rq)
-{
-	INIT_WORK(&rq->mq_flush_data, mq_flush_data_run);
-	kblockd_schedule_work(rq->q, &rq->mq_flush_data);
+		blk_mq_add_to_requeue_list(rq, add_front);
+		blk_mq_kick_requeue_list(q);
+		return false;
+	} else {
+		if (add_front)
+			list_add(&rq->queuelist, &rq->q->queue_head);
+		else
+			list_add_tail(&rq->queuelist, &rq->q->queue_head);
+		return true;
+	}
 }
 
 /**
@@ -187,12 +188,7 @@ static bool blk_flush_complete_seq(struct request *rq, unsigned int seq,
 
 	case REQ_FSEQ_DATA:
 		list_move_tail(&rq->flush.list, &q->flush_data_in_flight);
-		if (q->mq_ops)
-			blk_mq_flush_data_insert(rq);
-		else {
-			list_add(&rq->queuelist, &q->queue_head);
-			queued = true;
-		}
+		queued = blk_flush_queue_rq(rq, true);
 		break;
 
 	case REQ_FSEQ_DONE:
@@ -216,9 +212,6 @@ static bool blk_flush_complete_seq(struct request *rq, unsigned int seq,
 	}
 
 	kicked = blk_kick_flush(q);
-	/* blk_mq_run_flush will run queue */
-	if (q->mq_ops)
-		return queued;
 	return kicked | queued;
 }
 
@@ -231,9 +224,10 @@ static void flush_end_io(struct request *flush_rq, int error)
 	unsigned long flags = 0;
 
 	if (q->mq_ops) {
-		blk_mq_free_request(flush_rq);
 		spin_lock_irqsave(&q->mq_flush_lock, flags);
+		q->flush_rq->tag = -1;
 	}
+
 	running = &q->flush_queue[q->flush_running_idx];
 	BUG_ON(q->flush_pending_idx == q->flush_running_idx);
 
@@ -263,49 +257,14 @@ static void flush_end_io(struct request *flush_rq, int error)
 	 * kblockd.
 	 */
 	if (queued || q->flush_queue_delayed) {
-		if (!q->mq_ops)
-			blk_run_queue_async(q);
-		else
-		/*
-		 * This can be optimized to only run queues with requests
-		 * queued if necessary.
-		 */
-			blk_mq_run_queues(q, true);
+		WARN_ON(q->mq_ops);
+		blk_run_queue_async(q);
 	}
 	q->flush_queue_delayed = 0;
 	if (q->mq_ops)
 		spin_unlock_irqrestore(&q->mq_flush_lock, flags);
 }
 
-static void mq_flush_work(struct work_struct *work)
-{
-	struct request_queue *q;
-	struct request *rq;
-
-	q = container_of(work, struct request_queue, mq_flush_work);
-
-	/* We don't need set REQ_FLUSH_SEQ, it's for consistency */
-	rq = blk_mq_alloc_request(q, WRITE_FLUSH|REQ_FLUSH_SEQ,
-		__GFP_WAIT|GFP_ATOMIC, true);
-	rq->cmd_type = REQ_TYPE_FS;
-	rq->end_io = flush_end_io;
-
-	blk_mq_run_request(rq, true, false);
-}
-
-/*
- * We can't directly use q->flush_rq, because it doesn't have tag and is not in
- * hctx->rqs[]. so we must allocate a new request, since we can't sleep here,
- * so offload the work to workqueue.
- *
- * Note: we assume a flush request finished in any hardware queue will flush
- * the whole disk cache.
- */
-static void mq_run_flush(struct request_queue *q)
-{
-	kblockd_schedule_work(q, &q->mq_flush_work);
-}
-
 /**
  * blk_kick_flush - consider issuing flush request
  * @q: request_queue being kicked
@@ -340,19 +299,17 @@ static bool blk_kick_flush(struct request_queue *q)
 	 * different from running_idx, which means flush is in flight.
 	 */
 	q->flush_pending_idx ^= 1;
-	if (q->mq_ops) {
-		mq_run_flush(q);
-		return true;
-	}
 
-	blk_rq_init(q, &q->flush_rq);
-	q->flush_rq.cmd_type = REQ_TYPE_FS;
-	q->flush_rq.cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ;
-	q->flush_rq.rq_disk = first_rq->rq_disk;
-	q->flush_rq.end_io = flush_end_io;
+	blk_rq_init(q, q->flush_rq);
+	if (q->mq_ops)
+		blk_mq_clone_flush_request(q->flush_rq, first_rq);
+
+	q->flush_rq->cmd_type = REQ_TYPE_FS;
+	q->flush_rq->cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ;
+	q->flush_rq->rq_disk = first_rq->rq_disk;
+	q->flush_rq->end_io = flush_end_io;
 
-	list_add_tail(&q->flush_rq.queuelist, &q->queue_head);
-	return true;
+	return blk_flush_queue_rq(q->flush_rq, false);
 }
 
 static void flush_data_end_io(struct request *rq, int error)
@@ -437,7 +394,7 @@ void blk_insert_flush(struct request *rq)
 	if ((policy & REQ_FSEQ_DATA) &&
 	    !(policy & (REQ_FSEQ_PREFLUSH | REQ_FSEQ_POSTFLUSH))) {
 		if (q->mq_ops) {
-			blk_mq_run_request(rq, false, true);
+			blk_mq_insert_request(rq, false, false, true);
 		} else
 			list_add_tail(&rq->queuelist, &q->queue_head);
 		return;
@@ -465,53 +422,6 @@ void blk_insert_flush(struct request *rq)
 }
 
 /**
- * blk_abort_flushes - @q is being aborted, abort flush requests
- * @q: request_queue being aborted
- *
- * To be called from elv_abort_queue().  @q is being aborted.  Prepare all
- * FLUSH/FUA requests for abortion.
- *
- * CONTEXT:
- * spin_lock_irq(q->queue_lock)
- */
-void blk_abort_flushes(struct request_queue *q)
-{
-	struct request *rq, *n;
-	int i;
-
-	/*
-	 * Requests in flight for data are already owned by the dispatch
-	 * queue or the device driver.  Just restore for normal completion.
-	 */
-	list_for_each_entry_safe(rq, n, &q->flush_data_in_flight, flush.list) {
-		list_del_init(&rq->flush.list);
-		blk_flush_restore_request(rq);
-	}
-
-	/*
-	 * We need to give away requests on flush queues.  Restore for
-	 * normal completion and put them on the dispatch queue.
-	 */
-	for (i = 0; i < ARRAY_SIZE(q->flush_queue); i++) {
-		list_for_each_entry_safe(rq, n, &q->flush_queue[i],
-					 flush.list) {
-			list_del_init(&rq->flush.list);
-			blk_flush_restore_request(rq);
-			list_add_tail(&rq->queuelist, &q->queue_head);
-		}
-	}
-}
-
-static void bio_end_flush(struct bio *bio, int err)
-{
-	if (err)
-		clear_bit(BIO_UPTODATE, &bio->bi_flags);
-	if (bio->bi_private)
-		complete(bio->bi_private);
-	bio_put(bio);
-}
-
-/**
  * blkdev_issue_flush - queue a flush
  * @bdev:	blockdev to issue flush for
  * @gfp_mask:	memory allocation flags (for bio_alloc)
@@ -526,7 +436,6 @@ static void bio_end_flush(struct bio *bio, int err)
 int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
 		sector_t *error_sector)
 {
-	DECLARE_COMPLETION_ONSTACK(wait);
 	struct request_queue *q;
 	struct bio *bio;
 	int ret = 0;
@@ -548,13 +457,9 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
 		return -ENXIO;
 
 	bio = bio_alloc(gfp_mask, 0);
-	bio->bi_end_io = bio_end_flush;
 	bio->bi_bdev = bdev;
-	bio->bi_private = &wait;
 
-	bio_get(bio);
-	submit_bio(WRITE_FLUSH, bio);
-	wait_for_completion_io(&wait);
+	ret = submit_bio_wait(WRITE_FLUSH, bio);
 
 	/*
 	 * The driver must store the error location in ->bi_sector, if
@@ -562,10 +467,7 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
 	 * copied from blk_rq_pos(rq).
 	 */
 	if (error_sector)
-		*error_sector = bio->bi_sector;
-
-	if (!bio_flagged(bio, BIO_UPTODATE))
-		ret = -EIO;
+		*error_sector = bio->bi_iter.bi_sector;
 
 	bio_put(bio);
 	return ret;
@@ -575,5 +477,4 @@ EXPORT_SYMBOL(blkdev_issue_flush);
 void blk_mq_init_flush(struct request_queue *q)
 {
 	spin_lock_init(&q->mq_flush_lock);
-	INIT_WORK(&q->mq_flush_work, mq_flush_work);
 }