From 73c101011926c5832e6e141682180c4debe2cf45 Mon Sep 17 00:00:00 2001
From: Jens Axboe <jaxboe@fusionio.com>
Date: Tue, 8 Mar 2011 13:19:51 +0100
Subject: block: initial patch for on-stack per-task plugging

This patch adds support for creating a queuing context outside
of the queue itself. This enables us to batch up pieces of IO
before grabbing the block device queue lock and submitting them to
the IO scheduler.

The context is created on the stack of the process and assigned in
the task structure, so that we can auto-unplug it if we hit a schedule
event.

The current queue plugging happens implicitly if IO is submitted to
an empty device, yet callers have to remember to unplug that IO when
they are going to wait for it. This is an ugly API and has caused bugs
in the past. Additionally, it requires hacks in the vm (->sync_page()
callback) to handle that logic. By switching to an explicit plugging
scheme we make the API a lot nicer and can get rid of the ->sync_page()
hack in the vm.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
---
 block/elevator.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

(limited to 'block/elevator.c')

diff --git a/block/elevator.c b/block/elevator.c
index f98e92edc93..25713927c0d 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -113,7 +113,7 @@ int elv_rq_merge_ok(struct request *rq, struct bio *bio)
 }
 EXPORT_SYMBOL(elv_rq_merge_ok);
 
-static inline int elv_try_merge(struct request *__rq, struct bio *bio)
+int elv_try_merge(struct request *__rq, struct bio *bio)
 {
 	int ret = ELEVATOR_NO_MERGE;
 
@@ -421,6 +421,8 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq)
 	struct list_head *entry;
 	int stop_flags;
 
+	BUG_ON(rq->cmd_flags & REQ_ON_PLUG);
+
 	if (q->last_merge == rq)
 		q->last_merge = NULL;
 
@@ -696,6 +698,8 @@ void elv_insert(struct request_queue *q, struct request *rq, int where)
 void __elv_add_request(struct request_queue *q, struct request *rq, int where,
 		       int plug)
 {
+	BUG_ON(rq->cmd_flags & REQ_ON_PLUG);
+
 	if (rq->cmd_flags & REQ_SOFTBARRIER) {
 		/* barriers are scheduling boundary, update end_sector */
 		if (rq->cmd_type == REQ_TYPE_FS ||
-- 
cgit v1.2.3


From 7eaceaccab5f40bbfda044629a6298616aeaed50 Mon Sep 17 00:00:00 2001
From: Jens Axboe <jaxboe@fusionio.com>
Date: Thu, 10 Mar 2011 08:52:07 +0100
Subject: block: remove per-queue plugging

Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
---
 Documentation/block/biodoc.txt      |   5 --
 block/blk-core.c                    | 173 +++++-------------------------------
 block/blk-exec.c                    |   4 +-
 block/blk-flush.c                   |   3 +-
 block/blk-settings.c                |   8 --
 block/blk-throttle.c                |   1 -
 block/blk.h                         |   2 -
 block/cfq-iosched.c                 |   8 --
 block/deadline-iosched.c            |   9 --
 block/elevator.c                    |  43 +--------
 block/noop-iosched.c                |   8 --
 drivers/block/cciss.c               |   6 --
 drivers/block/cpqarray.c            |   3 -
 drivers/block/drbd/drbd_actlog.c    |   2 -
 drivers/block/drbd/drbd_bitmap.c    |   1 -
 drivers/block/drbd/drbd_int.h       |  14 ---
 drivers/block/drbd/drbd_main.c      |  33 +------
 drivers/block/drbd/drbd_receiver.c  |  20 +----
 drivers/block/drbd/drbd_req.c       |   4 -
 drivers/block/drbd/drbd_worker.c    |   1 -
 drivers/block/drbd/drbd_wrappers.h  |  18 ----
 drivers/block/floppy.c              |   1 -
 drivers/block/loop.c                |  13 ---
 drivers/block/pktcdvd.c             |   2 -
 drivers/block/umem.c                |  16 +---
 drivers/ide/ide-atapi.c             |   3 +-
 drivers/ide/ide-io.c                |   4 -
 drivers/ide/ide-park.c              |   2 +-
 drivers/md/bitmap.c                 |   3 +-
 drivers/md/dm-crypt.c               |   9 +-
 drivers/md/dm-kcopyd.c              |  52 ++---------
 drivers/md/dm-raid.c                |   2 +-
 drivers/md/dm-raid1.c               |   2 -
 drivers/md/dm-table.c               |  24 -----
 drivers/md/dm.c                     |  33 ++-----
 drivers/md/linear.c                 |  17 ----
 drivers/md/md.c                     |   7 --
 drivers/md/multipath.c              |  31 -------
 drivers/md/raid0.c                  |  16 ----
 drivers/md/raid1.c                  |  83 ++++-------------
 drivers/md/raid10.c                 |  87 ++++--------------
 drivers/md/raid5.c                  |  62 ++-----------
 drivers/md/raid5.h                  |   2 +-
 drivers/message/i2o/i2o_block.c     |   6 +-
 drivers/mmc/card/queue.c            |   3 +-
 drivers/s390/block/dasd.c           |   2 +-
 drivers/s390/char/tape_block.c      |   1 -
 drivers/scsi/scsi_transport_fc.c    |   2 +-
 drivers/scsi/scsi_transport_sas.c   |   6 +-
 drivers/target/target_core_iblock.c |   7 +-
 fs/adfs/inode.c                     |   1 -
 fs/affs/file.c                      |   2 -
 fs/aio.c                            |   4 +-
 fs/befs/linuxvfs.c                  |   1 -
 fs/bfs/file.c                       |   1 -
 fs/block_dev.c                      |   1 -
 fs/btrfs/disk-io.c                  |  79 ----------------
 fs/btrfs/inode.c                    |   1 -
 fs/btrfs/volumes.c                  |  91 +++----------------
 fs/buffer.c                         |  31 +------
 fs/cifs/file.c                      |  30 -------
 fs/direct-io.c                      |   5 +-
 fs/efs/inode.c                      |   1 -
 fs/exofs/inode.c                    |   1 -
 fs/ext2/inode.c                     |   2 -
 fs/ext3/inode.c                     |   3 -
 fs/ext4/inode.c                     |   4 -
 fs/fat/inode.c                      |   1 -
 fs/freevxfs/vxfs_subr.c             |   1 -
 fs/fuse/inode.c                     |   1 -
 fs/gfs2/aops.c                      |   3 -
 fs/gfs2/meta_io.c                   |   1 -
 fs/hfs/inode.c                      |   2 -
 fs/hfsplus/inode.c                  |   2 -
 fs/hpfs/file.c                      |   1 -
 fs/isofs/inode.c                    |   1 -
 fs/jfs/inode.c                      |   1 -
 fs/jfs/jfs_metapage.c               |   1 -
 fs/logfs/dev_bdev.c                 |   2 -
 fs/minix/inode.c                    |   1 -
 fs/nilfs2/btnode.c                  |   6 +-
 fs/nilfs2/gcinode.c                 |   1 -
 fs/nilfs2/inode.c                   |   1 -
 fs/nilfs2/mdt.c                     |   9 +-
 fs/nilfs2/page.c                    |   5 +-
 fs/nilfs2/page.h                    |   3 +-
 fs/ntfs/aops.c                      |   4 -
 fs/ntfs/compress.c                  |   3 +-
 fs/ocfs2/aops.c                     |   1 -
 fs/ocfs2/cluster/heartbeat.c        |   4 -
 fs/omfs/file.c                      |   1 -
 fs/qnx4/inode.c                     |   1 -
 fs/reiserfs/inode.c                 |   1 -
 fs/sysv/itree.c                     |   1 -
 fs/ubifs/super.c                    |   1 -
 fs/udf/file.c                       |   1 -
 fs/udf/inode.c                      |   1 -
 fs/ufs/inode.c                      |   1 -
 fs/ufs/truncate.c                   |   2 +-
 fs/xfs/linux-2.6/xfs_aops.c         |   1 -
 fs/xfs/linux-2.6/xfs_buf.c          |  13 ++-
 include/linux/backing-dev.h         |  16 ----
 include/linux/blkdev.h              |  31 ++-----
 include/linux/buffer_head.h         |   1 -
 include/linux/device-mapper.h       |   5 --
 include/linux/elevator.h            |   7 +-
 include/linux/fs.h                  |   1 -
 include/linux/pagemap.h             |  12 ---
 include/linux/swap.h                |   2 -
 mm/backing-dev.c                    |   6 --
 mm/filemap.c                        |  67 ++------------
 mm/memory-failure.c                 |   8 +-
 mm/nommu.c                          |   4 -
 mm/page-writeback.c                 |   2 +-
 mm/readahead.c                      |  12 ---
 mm/shmem.c                          |   1 -
 mm/swap_state.c                     |   5 +-
 mm/swapfile.c                       |  37 --------
 mm/vmscan.c                         |   2 +-
 119 files changed, 151 insertions(+), 1269 deletions(-)

(limited to 'block/elevator.c')

diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index b9a83dd2473..2a7b38c832c 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -963,11 +963,6 @@ elevator_dispatch_fn*		fills the dispatch queue with ready requests.
 
 elevator_add_req_fn*		called to add a new request into the scheduler
 
-elevator_queue_empty_fn		returns true if the merge queue is empty.
-				Drivers shouldn't use this, but rather check
-				if elv_next_request is NULL (without losing the
-				request if one exists!)
-
 elevator_former_req_fn
 elevator_latter_req_fn		These return the request before or after the
 				one specified in disk sort order. Used by the
diff --git a/block/blk-core.c b/block/blk-core.c
index 6efb55cc5af..82a45898ba7 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -198,6 +198,19 @@ void blk_dump_rq_flags(struct request *rq, char *msg)
 }
 EXPORT_SYMBOL(blk_dump_rq_flags);
 
+/*
+ * Make sure that plugs that were pending when this function was entered,
+ * are now complete and requests pushed to the queue.
+*/
+static inline void queue_sync_plugs(struct request_queue *q)
+{
+	/*
+	 * If the current process is plugged and has barriers submitted,
+	 * we will livelock if we don't unplug first.
+	 */
+	blk_flush_plug(current);
+}
+
 static void blk_delay_work(struct work_struct *work)
 {
 	struct request_queue *q;
@@ -224,137 +237,6 @@ void blk_delay_queue(struct request_queue *q, unsigned long msecs)
 }
 EXPORT_SYMBOL(blk_delay_queue);
 
-/*
- * "plug" the device if there are no outstanding requests: this will
- * force the transfer to start only after we have put all the requests
- * on the list.
- *
- * This is called with interrupts off and no requests on the queue and
- * with the queue lock held.
- */
-void blk_plug_device(struct request_queue *q)
-{
-	WARN_ON(!irqs_disabled());
-
-	/*
-	 * don't plug a stopped queue, it must be paired with blk_start_queue()
-	 * which will restart the queueing
-	 */
-	if (blk_queue_stopped(q))
-		return;
-
-	if (!queue_flag_test_and_set(QUEUE_FLAG_PLUGGED, q)) {
-		mod_timer(&q->unplug_timer, jiffies + q->unplug_delay);
-		trace_block_plug(q);
-	}
-}
-EXPORT_SYMBOL(blk_plug_device);
-
-/**
- * blk_plug_device_unlocked - plug a device without queue lock held
- * @q:    The &struct request_queue to plug
- *
- * Description:
- *   Like @blk_plug_device(), but grabs the queue lock and disables
- *   interrupts.
- **/
-void blk_plug_device_unlocked(struct request_queue *q)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(q->queue_lock, flags);
-	blk_plug_device(q);
-	spin_unlock_irqrestore(q->queue_lock, flags);
-}
-EXPORT_SYMBOL(blk_plug_device_unlocked);
-
-/*
- * remove the queue from the plugged list, if present. called with
- * queue lock held and interrupts disabled.
- */
-int blk_remove_plug(struct request_queue *q)
-{
-	WARN_ON(!irqs_disabled());
-
-	if (!queue_flag_test_and_clear(QUEUE_FLAG_PLUGGED, q))
-		return 0;
-
-	del_timer(&q->unplug_timer);
-	return 1;
-}
-EXPORT_SYMBOL(blk_remove_plug);
-
-/*
- * remove the plug and let it rip..
- */
-void __generic_unplug_device(struct request_queue *q)
-{
-	if (unlikely(blk_queue_stopped(q)))
-		return;
-	if (!blk_remove_plug(q) && !blk_queue_nonrot(q))
-		return;
-
-	q->request_fn(q);
-}
-
-/**
- * generic_unplug_device - fire a request queue
- * @q:    The &struct request_queue in question
- *
- * Description:
- *   Linux uses plugging to build bigger requests queues before letting
- *   the device have at them. If a queue is plugged, the I/O scheduler
- *   is still adding and merging requests on the queue. Once the queue
- *   gets unplugged, the request_fn defined for the queue is invoked and
- *   transfers started.
- **/
-void generic_unplug_device(struct request_queue *q)
-{
-	if (blk_queue_plugged(q)) {
-		spin_lock_irq(q->queue_lock);
-		__generic_unplug_device(q);
-		spin_unlock_irq(q->queue_lock);
-	}
-}
-EXPORT_SYMBOL(generic_unplug_device);
-
-static void blk_backing_dev_unplug(struct backing_dev_info *bdi,
-				   struct page *page)
-{
-	struct request_queue *q = bdi->unplug_io_data;
-
-	blk_unplug(q);
-}
-
-void blk_unplug_work(struct work_struct *work)
-{
-	struct request_queue *q =
-		container_of(work, struct request_queue, unplug_work);
-
-	trace_block_unplug_io(q);
-	q->unplug_fn(q);
-}
-
-void blk_unplug_timeout(unsigned long data)
-{
-	struct request_queue *q = (struct request_queue *)data;
-
-	trace_block_unplug_timer(q);
-	kblockd_schedule_work(q, &q->unplug_work);
-}
-
-void blk_unplug(struct request_queue *q)
-{
-	/*
-	 * devices don't necessarily have an ->unplug_fn defined
-	 */
-	if (q->unplug_fn) {
-		trace_block_unplug_io(q);
-		q->unplug_fn(q);
-	}
-}
-EXPORT_SYMBOL(blk_unplug);
-
 /**
  * blk_start_queue - restart a previously stopped queue
  * @q:    The &struct request_queue in question
@@ -389,7 +271,6 @@ EXPORT_SYMBOL(blk_start_queue);
  **/
 void blk_stop_queue(struct request_queue *q)
 {
-	blk_remove_plug(q);
 	cancel_delayed_work(&q->delay_work);
 	queue_flag_set(QUEUE_FLAG_STOPPED, q);
 }
@@ -411,11 +292,10 @@ EXPORT_SYMBOL(blk_stop_queue);
  */
 void blk_sync_queue(struct request_queue *q)
 {
-	del_timer_sync(&q->unplug_timer);
 	del_timer_sync(&q->timeout);
-	cancel_work_sync(&q->unplug_work);
 	throtl_shutdown_timer_wq(q);
 	cancel_delayed_work_sync(&q->delay_work);
+	queue_sync_plugs(q);
 }
 EXPORT_SYMBOL(blk_sync_queue);
 
@@ -430,14 +310,9 @@ EXPORT_SYMBOL(blk_sync_queue);
  */
 void __blk_run_queue(struct request_queue *q)
 {
-	blk_remove_plug(q);
-
 	if (unlikely(blk_queue_stopped(q)))
 		return;
 
-	if (elv_queue_empty(q))
-		return;
-
 	/*
 	 * Only recurse once to avoid overrunning the stack, let the unplug
 	 * handling reinvoke the handler shortly if we already got there.
@@ -445,10 +320,8 @@ void __blk_run_queue(struct request_queue *q)
 	if (!queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) {
 		q->request_fn(q);
 		queue_flag_clear(QUEUE_FLAG_REENTER, q);
-	} else {
-		queue_flag_set(QUEUE_FLAG_PLUGGED, q);
-		kblockd_schedule_work(q, &q->unplug_work);
-	}
+	} else
+		queue_delayed_work(kblockd_workqueue, &q->delay_work, 0);
 }
 EXPORT_SYMBOL(__blk_run_queue);
 
@@ -535,8 +408,6 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
 	if (!q)
 		return NULL;
 
-	q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug;
-	q->backing_dev_info.unplug_io_data = q;
 	q->backing_dev_info.ra_pages =
 			(VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
 	q->backing_dev_info.state = 0;
@@ -556,13 +427,11 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
 
 	setup_timer(&q->backing_dev_info.laptop_mode_wb_timer,
 		    laptop_mode_timer_fn, (unsigned long) q);
-	init_timer(&q->unplug_timer);
 	setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q);
 	INIT_LIST_HEAD(&q->timeout_list);
 	INIT_LIST_HEAD(&q->flush_queue[0]);
 	INIT_LIST_HEAD(&q->flush_queue[1]);
 	INIT_LIST_HEAD(&q->flush_data_in_flight);
-	INIT_WORK(&q->unplug_work, blk_unplug_work);
 	INIT_DELAYED_WORK(&q->delay_work, blk_delay_work);
 
 	kobject_init(&q->kobj, &blk_queue_ktype);
@@ -652,7 +521,6 @@ blk_init_allocated_queue_node(struct request_queue *q, request_fn_proc *rfn,
 	q->request_fn		= rfn;
 	q->prep_rq_fn		= NULL;
 	q->unprep_rq_fn		= NULL;
-	q->unplug_fn		= generic_unplug_device;
 	q->queue_flags		= QUEUE_FLAG_DEFAULT;
 	q->queue_lock		= lock;
 
@@ -910,8 +778,8 @@ out:
 }
 
 /*
- * No available requests for this queue, unplug the device and wait for some
- * requests to become available.
+ * No available requests for this queue, wait for some requests to become
+ * available.
  *
  * Called with q->queue_lock held, and returns with it unlocked.
  */
@@ -932,7 +800,6 @@ static struct request *get_request_wait(struct request_queue *q, int rw_flags,
 
 		trace_block_sleeprq(q, bio, rw_flags & 1);
 
-		__generic_unplug_device(q);
 		spin_unlock_irq(q->queue_lock);
 		io_schedule();
 
@@ -1058,7 +925,7 @@ static void add_acct_request(struct request_queue *q, struct request *rq,
 			     int where)
 {
 	drive_stat_acct(rq, 1);
-	__elv_add_request(q, rq, where, 0);
+	__elv_add_request(q, rq, where);
 }
 
 /**
@@ -2798,7 +2665,7 @@ static void flush_plug_list(struct blk_plug *plug)
 		/*
 		 * rq is already accounted, so use raw insert
 		 */
-		__elv_add_request(q, rq, ELEVATOR_INSERT_SORT, 0);
+		__elv_add_request(q, rq, ELEVATOR_INSERT_SORT);
 	}
 
 	if (q) {
diff --git a/block/blk-exec.c b/block/blk-exec.c
index cf1456a02ac..81e31819a59 100644
--- a/block/blk-exec.c
+++ b/block/blk-exec.c
@@ -54,8 +54,8 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk,
 	rq->end_io = done;
 	WARN_ON(irqs_disabled());
 	spin_lock_irq(q->queue_lock);
-	__elv_add_request(q, rq, where, 1);
-	__generic_unplug_device(q);
+	__elv_add_request(q, rq, where);
+	__blk_run_queue(q);
 	/* the queue is stopped so it won't be plugged+unplugged */
 	if (rq->cmd_type == REQ_TYPE_PM_RESUME)
 		q->request_fn(q);
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 1e2aa8a8908..671fa9da756 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -194,7 +194,6 @@ static void flush_end_io(struct request *flush_rq, int error)
 {
 	struct request_queue *q = flush_rq->q;
 	struct list_head *running = &q->flush_queue[q->flush_running_idx];
-	bool was_empty = elv_queue_empty(q);
 	bool queued = false;
 	struct request *rq, *n;
 
@@ -213,7 +212,7 @@ static void flush_end_io(struct request *flush_rq, int error)
 	}
 
 	/* after populating an empty queue, kick it to avoid stall */
-	if (queued && was_empty)
+	if (queued)
 		__blk_run_queue(q);
 }
 
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 36c8c1f2af1..c8d68921ddd 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -164,14 +164,6 @@ void blk_queue_make_request(struct request_queue *q, make_request_fn *mfn)
 	blk_queue_congestion_threshold(q);
 	q->nr_batching = BLK_BATCH_REQ;
 
-	q->unplug_thresh = 4;		/* hmm */
-	q->unplug_delay = msecs_to_jiffies(3);	/* 3 milliseconds */
-	if (q->unplug_delay == 0)
-		q->unplug_delay = 1;
-
-	q->unplug_timer.function = blk_unplug_timeout;
-	q->unplug_timer.data = (unsigned long)q;
-
 	blk_set_default_limits(&q->limits);
 	blk_queue_max_hw_sectors(q, BLK_SAFE_MAX_SECTORS);
 
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index a89043a3caa..b8dcdc2663a 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -800,7 +800,6 @@ out:
 	if (nr_disp) {
 		while((bio = bio_list_pop(&bio_list_on_stack)))
 			generic_make_request(bio);
-		blk_unplug(q);
 	}
 	return nr_disp;
 }
diff --git a/block/blk.h b/block/blk.h
index 284b500852b..49d21af81d0 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -18,8 +18,6 @@ int blk_rq_append_bio(struct request_queue *q, struct request *rq,
 void blk_dequeue_request(struct request *rq);
 void __blk_queue_free_tags(struct request_queue *q);
 
-void blk_unplug_work(struct work_struct *work);
-void blk_unplug_timeout(unsigned long data);
 void blk_rq_timed_out_timer(unsigned long data);
 void blk_delete_timer(struct request *);
 void blk_add_timer(struct request *);
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 3202c7e87fb..ef631539dd2 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -499,13 +499,6 @@ static inline void cfq_schedule_dispatch(struct cfq_data *cfqd)
 	}
 }
 
-static int cfq_queue_empty(struct request_queue *q)
-{
-	struct cfq_data *cfqd = q->elevator->elevator_data;
-
-	return !cfqd->rq_queued;
-}
-
 /*
  * Scale schedule slice based on io priority. Use the sync time slice only
  * if a queue is marked sync and has sync io queued. A sync queue with async
@@ -4061,7 +4054,6 @@ static struct elevator_type iosched_cfq = {
 		.elevator_add_req_fn =		cfq_insert_request,
 		.elevator_activate_req_fn =	cfq_activate_request,
 		.elevator_deactivate_req_fn =	cfq_deactivate_request,
-		.elevator_queue_empty_fn =	cfq_queue_empty,
 		.elevator_completed_req_fn =	cfq_completed_request,
 		.elevator_former_req_fn =	elv_rb_former_request,
 		.elevator_latter_req_fn =	elv_rb_latter_request,
diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c
index b547cbca7b2..5139c0ea186 100644
--- a/block/deadline-iosched.c
+++ b/block/deadline-iosched.c
@@ -326,14 +326,6 @@ dispatch_request:
 	return 1;
 }
 
-static int deadline_queue_empty(struct request_queue *q)
-{
-	struct deadline_data *dd = q->elevator->elevator_data;
-
-	return list_empty(&dd->fifo_list[WRITE])
-		&& list_empty(&dd->fifo_list[READ]);
-}
-
 static void deadline_exit_queue(struct elevator_queue *e)
 {
 	struct deadline_data *dd = e->elevator_data;
@@ -445,7 +437,6 @@ static struct elevator_type iosched_deadline = {
 		.elevator_merge_req_fn =	deadline_merged_requests,
 		.elevator_dispatch_fn =		deadline_dispatch_requests,
 		.elevator_add_req_fn =		deadline_add_request,
-		.elevator_queue_empty_fn =	deadline_queue_empty,
 		.elevator_former_req_fn =	elv_rb_former_request,
 		.elevator_latter_req_fn =	elv_rb_latter_request,
 		.elevator_init_fn =		deadline_init_queue,
diff --git a/block/elevator.c b/block/elevator.c
index 25713927c0d..3ea208256e7 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -619,21 +619,12 @@ void elv_quiesce_end(struct request_queue *q)
 
 void elv_insert(struct request_queue *q, struct request *rq, int where)
 {
-	int unplug_it = 1;
-
 	trace_block_rq_insert(q, rq);
 
 	rq->q = q;
 
 	switch (where) {
 	case ELEVATOR_INSERT_REQUEUE:
-		/*
-		 * Most requeues happen because of a busy condition,
-		 * don't force unplug of the queue for that case.
-		 * Clear unplug_it and fall through.
-		 */
-		unplug_it = 0;
-
 	case ELEVATOR_INSERT_FRONT:
 		rq->cmd_flags |= REQ_SOFTBARRIER;
 		list_add(&rq->queuelist, &q->queue_head);
@@ -679,24 +670,14 @@ void elv_insert(struct request_queue *q, struct request *rq, int where)
 		rq->cmd_flags |= REQ_SOFTBARRIER;
 		blk_insert_flush(rq);
 		break;
-
 	default:
 		printk(KERN_ERR "%s: bad insertion point %d\n",
 		       __func__, where);
 		BUG();
 	}
-
-	if (unplug_it && blk_queue_plugged(q)) {
-		int nrq = q->rq.count[BLK_RW_SYNC] + q->rq.count[BLK_RW_ASYNC]
-				- queue_in_flight(q);
-
-		if (nrq >= q->unplug_thresh)
-			__generic_unplug_device(q);
-	}
 }
 
-void __elv_add_request(struct request_queue *q, struct request *rq, int where,
-		       int plug)
+void __elv_add_request(struct request_queue *q, struct request *rq, int where)
 {
 	BUG_ON(rq->cmd_flags & REQ_ON_PLUG);
 
@@ -711,38 +692,20 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where,
 		    where == ELEVATOR_INSERT_SORT)
 		where = ELEVATOR_INSERT_BACK;
 
-	if (plug)
-		blk_plug_device(q);
-
 	elv_insert(q, rq, where);
 }
 EXPORT_SYMBOL(__elv_add_request);
 
-void elv_add_request(struct request_queue *q, struct request *rq, int where,
-		     int plug)
+void elv_add_request(struct request_queue *q, struct request *rq, int where)
 {
 	unsigned long flags;
 
 	spin_lock_irqsave(q->queue_lock, flags);
-	__elv_add_request(q, rq, where, plug);
+	__elv_add_request(q, rq, where);
 	spin_unlock_irqrestore(q->queue_lock, flags);
 }
 EXPORT_SYMBOL(elv_add_request);
 
-int elv_queue_empty(struct request_queue *q)
-{
-	struct elevator_queue *e = q->elevator;
-
-	if (!list_empty(&q->queue_head))
-		return 0;
-
-	if (e->ops->elevator_queue_empty_fn)
-		return e->ops->elevator_queue_empty_fn(q);
-
-	return 1;
-}
-EXPORT_SYMBOL(elv_queue_empty);
-
 struct request *elv_latter_request(struct request_queue *q, struct request *rq)
 {
 	struct elevator_queue *e = q->elevator;
diff --git a/block/noop-iosched.c b/block/noop-iosched.c
index 232c4b38cd3..06389e9ef96 100644
--- a/block/noop-iosched.c
+++ b/block/noop-iosched.c
@@ -39,13 +39,6 @@ static void noop_add_request(struct request_queue *q, struct request *rq)
 	list_add_tail(&rq->queuelist, &nd->queue);
 }
 
-static int noop_queue_empty(struct request_queue *q)
-{
-	struct noop_data *nd = q->elevator->elevator_data;
-
-	return list_empty(&nd->queue);
-}
-
 static struct request *
 noop_former_request(struct request_queue *q, struct request *rq)
 {
@@ -90,7 +83,6 @@ static struct elevator_type elevator_noop = {
 		.elevator_merge_req_fn		= noop_merged_requests,
 		.elevator_dispatch_fn		= noop_dispatch,
 		.elevator_add_req_fn		= noop_add_request,
-		.elevator_queue_empty_fn	= noop_queue_empty,
 		.elevator_former_req_fn		= noop_former_request,
 		.elevator_latter_req_fn		= noop_latter_request,
 		.elevator_init_fn		= noop_init_queue,
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 9279272b373..35658f445fc 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -3170,12 +3170,6 @@ static void do_cciss_request(struct request_queue *q)
 	int sg_index = 0;
 	int chained = 0;
 
-	/* We call start_io here in case there is a command waiting on the
-	 * queue that has not been sent.
-	 */
-	if (blk_queue_plugged(q))
-		goto startio;
-
       queue:
 	creq = blk_peek_request(q);
 	if (!creq)
diff --git a/drivers/block/cpqarray.c b/drivers/block/cpqarray.c
index 946dad4caef..b2fceb53e80 100644
--- a/drivers/block/cpqarray.c
+++ b/drivers/block/cpqarray.c
@@ -911,9 +911,6 @@ static void do_ida_request(struct request_queue *q)
 	struct scatterlist tmp_sg[SG_MAX];
 	int i, dir, seg;
 
-	if (blk_queue_plugged(q))
-		goto startio;
-
 queue_next:
 	creq = blk_peek_request(q);
 	if (!creq)
diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c
index ba95cba192b..2096628d6e6 100644
--- a/drivers/block/drbd/drbd_actlog.c
+++ b/drivers/block/drbd/drbd_actlog.c
@@ -689,8 +689,6 @@ void drbd_al_to_on_disk_bm(struct drbd_conf *mdev)
 		}
 	}
 
-	drbd_blk_run_queue(bdev_get_queue(mdev->ldev->md_bdev));
-
 	/* always (try to) flush bitmap to stable storage */
 	drbd_md_flush(mdev);
 
diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index fd42832f785..0645ca829a9 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -840,7 +840,6 @@ static int bm_rw(struct drbd_conf *mdev, int rw) __must_hold(local)
 	for (i = 0; i < num_pages; i++)
 		bm_page_io_async(mdev, b, i, rw);
 
-	drbd_blk_run_queue(bdev_get_queue(mdev->ldev->md_bdev));
 	wait_event(b->bm_io_wait, atomic_read(&b->bm_async_io) == 0);
 
 	if (test_bit(BM_MD_IO_ERROR, &b->bm_flags)) {
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 3803a034893..0b5718e1958 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -2382,20 +2382,6 @@ static inline int drbd_queue_order_type(struct drbd_conf *mdev)
 	return QUEUE_ORDERED_NONE;
 }
 
-static inline void drbd_blk_run_queue(struct request_queue *q)
-{
-	if (q && q->unplug_fn)
-		q->unplug_fn(q);
-}
-
-static inline void drbd_kick_lo(struct drbd_conf *mdev)
-{
-	if (get_ldev(mdev)) {
-		drbd_blk_run_queue(bdev_get_queue(mdev->ldev->backing_bdev));
-		put_ldev(mdev);
-	}
-}
-
 static inline void drbd_md_flush(struct drbd_conf *mdev)
 {
 	int r;
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 29cd0dc9fe4..6049cb85310 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2719,35 +2719,6 @@ static int drbd_release(struct gendisk *gd, fmode_t mode)
 	return 0;
 }
 
-static void drbd_unplug_fn(struct request_queue *q)
-{
-	struct drbd_conf *mdev = q->queuedata;
-
-	/* unplug FIRST */
-	spin_lock_irq(q->queue_lock);
-	blk_remove_plug(q);
-	spin_unlock_irq(q->queue_lock);
-
-	/* only if connected */
-	spin_lock_irq(&mdev->req_lock);
-	if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
-		D_ASSERT(mdev->state.role == R_PRIMARY);
-		if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
-			/* add to the data.work queue,
-			 * unless already queued.
-			 * XXX this might be a good addition to drbd_queue_work
-			 * anyways, to detect "double queuing" ... */
-			if (list_empty(&mdev->unplug_work.list))
-				drbd_queue_work(&mdev->data.work,
-						&mdev->unplug_work);
-		}
-	}
-	spin_unlock_irq(&mdev->req_lock);
-
-	if (mdev->state.disk >= D_INCONSISTENT)
-		drbd_kick_lo(mdev);
-}
-
 static void drbd_set_defaults(struct drbd_conf *mdev)
 {
 	/* This way we get a compile error when sync_conf grows,
@@ -3222,9 +3193,7 @@ struct drbd_conf *drbd_new_device(unsigned int minor)
 	blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
 	blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
 	blk_queue_merge_bvec(q, drbd_merge_bvec);
-	q->queue_lock = &mdev->req_lock; /* needed since we use */
-		/* plugging on a queue, that actually has no requests! */
-	q->unplug_fn = drbd_unplug_fn;
+	q->queue_lock = &mdev->req_lock;
 
 	mdev->md_io_page = alloc_page(GFP_KERNEL);
 	if (!mdev->md_io_page)
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 24487d4fb20..84132f8bf8a 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -187,15 +187,6 @@ static struct page *drbd_pp_first_pages_or_try_alloc(struct drbd_conf *mdev, int
 	return NULL;
 }
 
-/* kick lower level device, if we have more than (arbitrary number)
- * reference counts on it, which typically are locally submitted io
- * requests.  don't use unacked_cnt, so we speed up proto A and B, too. */
-static void maybe_kick_lo(struct drbd_conf *mdev)
-{
-	if (atomic_read(&mdev->local_cnt) >= mdev->net_conf->unplug_watermark)
-		drbd_kick_lo(mdev);
-}
-
 static void reclaim_net_ee(struct drbd_conf *mdev, struct list_head *to_be_freed)
 {
 	struct drbd_epoch_entry *e;
@@ -219,7 +210,6 @@ static void drbd_kick_lo_and_reclaim_net(struct drbd_conf *mdev)
 	LIST_HEAD(reclaimed);
 	struct drbd_epoch_entry *e, *t;
 
-	maybe_kick_lo(mdev);
 	spin_lock_irq(&mdev->req_lock);
 	reclaim_net_ee(mdev, &reclaimed);
 	spin_unlock_irq(&mdev->req_lock);
@@ -436,8 +426,7 @@ void _drbd_wait_ee_list_empty(struct drbd_conf *mdev, struct list_head *head)
 	while (!list_empty(head)) {
 		prepare_to_wait(&mdev->ee_wait, &wait, TASK_UNINTERRUPTIBLE);
 		spin_unlock_irq(&mdev->req_lock);
-		drbd_kick_lo(mdev);
-		schedule();
+		io_schedule();
 		finish_wait(&mdev->ee_wait, &wait);
 		spin_lock_irq(&mdev->req_lock);
 	}
@@ -1147,7 +1136,6 @@ next_bio:
 
 		drbd_generic_make_request(mdev, fault_type, bio);
 	} while (bios);
-	maybe_kick_lo(mdev);
 	return 0;
 
 fail:
@@ -1167,9 +1155,6 @@ static int receive_Barrier(struct drbd_conf *mdev, enum drbd_packets cmd, unsign
 
 	inc_unacked(mdev);
 
-	if (mdev->net_conf->wire_protocol != DRBD_PROT_C)
-		drbd_kick_lo(mdev);
-
 	mdev->current_epoch->barrier_nr = p->barrier;
 	rv = drbd_may_finish_epoch(mdev, mdev->current_epoch, EV_GOT_BARRIER_NR);
 
@@ -3556,9 +3541,6 @@ static int receive_skip(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned
 
 static int receive_UnplugRemote(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
-	if (mdev->state.disk >= D_INCONSISTENT)
-		drbd_kick_lo(mdev);
-
 	/* Make sure we've acked all the TCP data associated
 	 * with the data requests being unplugged */
 	drbd_tcp_quickack(mdev->data.socket);
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 11a75d32a2e..ad3fc6228f2 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -960,10 +960,6 @@ allocate_barrier:
 			bio_endio(req->private_bio, -EIO);
 	}
 
-	/* we need to plug ALWAYS since we possibly need to kick lo_dev.
-	 * we plug after submit, so we won't miss an unplug event */
-	drbd_plug_device(mdev);
-
 	return 0;
 
 fail_conflicting:
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 34f224b018b..e027446590d 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -792,7 +792,6 @@ int drbd_resync_finished(struct drbd_conf *mdev)
 		 * queue (or even the read operations for those packets
 		 * is not finished by now).   Retry in 100ms. */
 
-		drbd_kick_lo(mdev);
 		__set_current_state(TASK_INTERRUPTIBLE);
 		schedule_timeout(HZ / 10);
 		w = kmalloc(sizeof(struct drbd_work), GFP_ATOMIC);
diff --git a/drivers/block/drbd/drbd_wrappers.h b/drivers/block/drbd/drbd_wrappers.h
index defdb5013ea..53586fa5ae1 100644
--- a/drivers/block/drbd/drbd_wrappers.h
+++ b/drivers/block/drbd/drbd_wrappers.h
@@ -45,24 +45,6 @@ static inline void drbd_generic_make_request(struct drbd_conf *mdev,
 		generic_make_request(bio);
 }
 
-static inline void drbd_plug_device(struct drbd_conf *mdev)
-{
-	struct request_queue *q;
-	q = bdev_get_queue(mdev->this_bdev);
-
-	spin_lock_irq(q->queue_lock);
-
-/* XXX the check on !blk_queue_plugged is redundant,
- * implicitly checked in blk_plug_device */
-
-	if (!blk_queue_plugged(q)) {
-		blk_plug_device(q);
-		del_timer(&q->unplug_timer);
-		/* unplugging should not happen automatically... */
-	}
-	spin_unlock_irq(q->queue_lock);
-}
-
 static inline int drbd_crypto_is_hash(struct crypto_tfm *tfm)
 {
         return (crypto_tfm_alg_type(tfm) & CRYPTO_ALG_TYPE_HASH_MASK)
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index b9ba04fc2b3..271142b9e2c 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -3837,7 +3837,6 @@ static int __floppy_read_block_0(struct block_device *bdev)
 	bio.bi_end_io = floppy_rb0_complete;
 
 	submit_bio(READ, &bio);
-	generic_unplug_device(bdev_get_queue(bdev));
 	process_fd_request();
 	wait_for_completion(&complete);
 
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 49e6a545eb6..01b8e4a87c9 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -541,17 +541,6 @@ out:
 	return 0;
 }
 
-/*
- * kick off io on the underlying address space
- */
-static void loop_unplug(struct request_queue *q)
-{
-	struct loop_device *lo = q->queuedata;
-
-	queue_flag_clear_unlocked(QUEUE_FLAG_PLUGGED, q);
-	blk_run_address_space(lo->lo_backing_file->f_mapping);
-}
-
 struct switch_request {
 	struct file *file;
 	struct completion wait;
@@ -918,7 +907,6 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
 	 */
 	blk_queue_make_request(lo->lo_queue, loop_make_request);
 	lo->lo_queue->queuedata = lo;
-	lo->lo_queue->unplug_fn = loop_unplug;
 
 	if (!(lo_flags & LO_FLAGS_READ_ONLY) && file->f_op->fsync)
 		blk_queue_flush(lo->lo_queue, REQ_FLUSH);
@@ -1020,7 +1008,6 @@ static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev)
 
 	kthread_stop(lo->lo_thread);
 
-	lo->lo_queue->unplug_fn = NULL;
 	lo->lo_backing_file = NULL;
 
 	loop_release_xfer(lo);
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 77d70eebb6b..d20e13f8000 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -1606,8 +1606,6 @@ static int kcdrwd(void *foobar)
 					min_sleep_time = pkt->sleep_time;
 			}
 
-			generic_unplug_device(bdev_get_queue(pd->bdev));
-
 			VPRINTK("kcdrwd: sleeping\n");
 			residue = schedule_timeout(min_sleep_time);
 			VPRINTK("kcdrwd: wake up\n");
diff --git a/drivers/block/umem.c b/drivers/block/umem.c
index 8be57151f5d..653439faa72 100644
--- a/drivers/block/umem.c
+++ b/drivers/block/umem.c
@@ -241,8 +241,7 @@ static void dump_dmastat(struct cardinfo *card, unsigned int dmastat)
  *
  * Whenever IO on the active page completes, the Ready page is activated
  * and the ex-Active page is clean out and made Ready.
- * Otherwise the Ready page is only activated when it becomes full, or
- * when mm_unplug_device is called via the unplug_io_fn.
+ * Otherwise the Ready page is only activated when it becomes full.
  *
  * If a request arrives while both pages a full, it is queued, and b_rdev is
  * overloaded to record whether it was a read or a write.
@@ -333,17 +332,6 @@ static inline void reset_page(struct mm_page *page)
 	page->biotail = &page->bio;
 }
 
-static void mm_unplug_device(struct request_queue *q)
-{
-	struct cardinfo *card = q->queuedata;
-	unsigned long flags;
-
-	spin_lock_irqsave(&card->lock, flags);
-	if (blk_remove_plug(q))
-		activate(card);
-	spin_unlock_irqrestore(&card->lock, flags);
-}
-
 /*
  * If there is room on Ready page, take
  * one bh off list and add it.
@@ -535,7 +523,6 @@ static int mm_make_request(struct request_queue *q, struct bio *bio)
 	*card->biotail = bio;
 	bio->bi_next = NULL;
 	card->biotail = &bio->bi_next;
-	blk_plug_device(q);
 	spin_unlock_irq(&card->lock);
 
 	return 0;
@@ -907,7 +894,6 @@ static int __devinit mm_pci_probe(struct pci_dev *dev,
 	blk_queue_make_request(card->queue, mm_make_request);
 	card->queue->queue_lock = &card->lock;
 	card->queue->queuedata = card;
-	card->queue->unplug_fn = mm_unplug_device;
 
 	tasklet_init(&card->tasklet, process_page, (unsigned long)card);
 
diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index e88a2cf1771..6f218e014e9 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -233,8 +233,7 @@ int ide_queue_sense_rq(ide_drive_t *drive, void *special)
 
 	drive->hwif->rq = NULL;
 
-	elv_add_request(drive->queue, &drive->sense_rq,
-			ELEVATOR_INSERT_FRONT, 0);
+	elv_add_request(drive->queue, &drive->sense_rq, ELEVATOR_INSERT_FRONT);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index 999dac054bc..f4077840d3a 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -549,8 +549,6 @@ plug_device_2:
 
 	if (rq)
 		blk_requeue_request(q, rq);
-	if (!elv_queue_empty(q))
-		blk_plug_device(q);
 }
 
 void ide_requeue_and_plug(ide_drive_t *drive, struct request *rq)
@@ -562,8 +560,6 @@ void ide_requeue_and_plug(ide_drive_t *drive, struct request *rq)
 
 	if (rq)
 		blk_requeue_request(q, rq);
-	if (!elv_queue_empty(q))
-		blk_plug_device(q);
 
 	spin_unlock_irqrestore(q->queue_lock, flags);
 }
diff --git a/drivers/ide/ide-park.c b/drivers/ide/ide-park.c
index 88a380c5a47..6ab9ab2a508 100644
--- a/drivers/ide/ide-park.c
+++ b/drivers/ide/ide-park.c
@@ -52,7 +52,7 @@ static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
 	rq->cmd[0] = REQ_UNPARK_HEADS;
 	rq->cmd_len = 1;
 	rq->cmd_type = REQ_TYPE_SPECIAL;
-	elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 1);
+	elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
 
 out:
 	return;
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 9a35320fb59..54bfc274b39 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1339,8 +1339,7 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect
 			prepare_to_wait(&bitmap->overflow_wait, &__wait,
 					TASK_UNINTERRUPTIBLE);
 			spin_unlock_irq(&bitmap->lock);
-			md_unplug(bitmap->mddev);
-			schedule();
+			io_schedule();
 			finish_wait(&bitmap->overflow_wait, &__wait);
 			continue;
 		}
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 4e054bd9166..2c62c1169f7 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -991,11 +991,6 @@ static void clone_init(struct dm_crypt_io *io, struct bio *clone)
 	clone->bi_destructor = dm_crypt_bio_destructor;
 }
 
-static void kcryptd_unplug(struct crypt_config *cc)
-{
-	blk_unplug(bdev_get_queue(cc->dev->bdev));
-}
-
 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
 {
 	struct crypt_config *cc = io->target->private;
@@ -1008,10 +1003,8 @@ static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
 	 * one in order to decrypt the whole bio data *afterwards*.
 	 */
 	clone = bio_alloc_bioset(gfp, bio_segments(base_bio), cc->bs);
-	if (!clone) {
-		kcryptd_unplug(cc);
+	if (!clone)
 		return 1;
-	}
 
 	crypt_inc_pending(io);
 
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
index 924f5f0084c..400cf35094a 100644
--- a/drivers/md/dm-kcopyd.c
+++ b/drivers/md/dm-kcopyd.c
@@ -37,13 +37,6 @@ struct dm_kcopyd_client {
 	unsigned int nr_pages;
 	unsigned int nr_free_pages;
 
-	/*
-	 * Block devices to unplug.
-	 * Non-NULL pointer means that a block device has some pending requests
-	 * and needs to be unplugged.
-	 */
-	struct block_device *unplug[2];
-
 	struct dm_io_client *io_client;
 
 	wait_queue_head_t destroyq;
@@ -315,31 +308,6 @@ static int run_complete_job(struct kcopyd_job *job)
 	return 0;
 }
 
-/*
- * Unplug the block device at the specified index.
- */
-static void unplug(struct dm_kcopyd_client *kc, int rw)
-{
-	if (kc->unplug[rw] != NULL) {
-		blk_unplug(bdev_get_queue(kc->unplug[rw]));
-		kc->unplug[rw] = NULL;
-	}
-}
-
-/*
- * Prepare block device unplug. If there's another device
- * to be unplugged at the same array index, we unplug that
- * device first.
- */
-static void prepare_unplug(struct dm_kcopyd_client *kc, int rw,
-			   struct block_device *bdev)
-{
-	if (likely(kc->unplug[rw] == bdev))
-		return;
-	unplug(kc, rw);
-	kc->unplug[rw] = bdev;
-}
-
 static void complete_io(unsigned long error, void *context)
 {
 	struct kcopyd_job *job = (struct kcopyd_job *) context;
@@ -386,15 +354,12 @@ static int run_io_job(struct kcopyd_job *job)
 		.client = job->kc->io_client,
 	};
 
-	if (job->rw == READ) {
+	if (job->rw == READ)
 		r = dm_io(&io_req, 1, &job->source, NULL);
-		prepare_unplug(job->kc, READ, job->source.bdev);
-	} else {
+	else {
 		if (job->num_dests > 1)
 			io_req.bi_rw |= REQ_UNPLUG;
 		r = dm_io(&io_req, job->num_dests, job->dests, NULL);
-		if (!(io_req.bi_rw & REQ_UNPLUG))
-			prepare_unplug(job->kc, WRITE, job->dests[0].bdev);
 	}
 
 	return r;
@@ -466,6 +431,7 @@ static void do_work(struct work_struct *work)
 {
 	struct dm_kcopyd_client *kc = container_of(work,
 					struct dm_kcopyd_client, kcopyd_work);
+	struct blk_plug plug;
 
 	/*
 	 * The order that these are called is *very* important.
@@ -473,18 +439,12 @@ static void do_work(struct work_struct *work)
 	 * Pages jobs when successful will jump onto the io jobs
 	 * list.  io jobs call wake when they complete and it all
 	 * starts again.
-	 *
-	 * Note that io_jobs add block devices to the unplug array,
-	 * this array is cleared with "unplug" calls. It is thus
-	 * forbidden to run complete_jobs after io_jobs and before
-	 * unplug because the block device could be destroyed in
-	 * job completion callback.
 	 */
+	blk_start_plug(&plug);
 	process_jobs(&kc->complete_jobs, kc, run_complete_job);
 	process_jobs(&kc->pages_jobs, kc, run_pages_job);
 	process_jobs(&kc->io_jobs, kc, run_io_job);
-	unplug(kc, READ);
-	unplug(kc, WRITE);
+	blk_finish_plug(&plug);
 }
 
 /*
@@ -665,8 +625,6 @@ int dm_kcopyd_client_create(unsigned int nr_pages,
 	INIT_LIST_HEAD(&kc->io_jobs);
 	INIT_LIST_HEAD(&kc->pages_jobs);
 
-	memset(kc->unplug, 0, sizeof(kc->unplug));
-
 	kc->job_pool = mempool_create_slab_pool(MIN_JOBS, _job_cache);
 	if (!kc->job_pool)
 		goto bad_slab;
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index b9e1e15ef11..5ef136cdba9 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -394,7 +394,7 @@ static void raid_unplug(struct dm_target_callbacks *cb)
 {
 	struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
 
-	md_raid5_unplug_device(rs->md.private);
+	md_raid5_kick_device(rs->md.private);
 }
 
 /*
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index dee326775c6..976ad4688af 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -842,8 +842,6 @@ static void do_mirror(struct work_struct *work)
 	do_reads(ms, &reads);
 	do_writes(ms, &writes);
 	do_failures(ms, &failures);
-
-	dm_table_unplug_all(ms->ti->table);
 }
 
 /*-----------------------------------------------------------------
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 38e4eb1bb96..f50a7b95225 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1275,29 +1275,6 @@ int dm_table_any_busy_target(struct dm_table *t)
 	return 0;
 }
 
-void dm_table_unplug_all(struct dm_table *t)
-{
-	struct dm_dev_internal *dd;
-	struct list_head *devices = dm_table_get_devices(t);
-	struct dm_target_callbacks *cb;
-
-	list_for_each_entry(dd, devices, list) {
-		struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev);
-		char b[BDEVNAME_SIZE];
-
-		if (likely(q))
-			blk_unplug(q);
-		else
-			DMWARN_LIMIT("%s: Cannot unplug nonexistent device %s",
-				     dm_device_name(t->md),
-				     bdevname(dd->dm_dev.bdev, b));
-	}
-
-	list_for_each_entry(cb, &t->target_callbacks, list)
-		if (cb->unplug_fn)
-			cb->unplug_fn(cb);
-}
-
 struct mapped_device *dm_table_get_md(struct dm_table *t)
 {
 	return t->md;
@@ -1345,4 +1322,3 @@ EXPORT_SYMBOL(dm_table_get_mode);
 EXPORT_SYMBOL(dm_table_get_md);
 EXPORT_SYMBOL(dm_table_put);
 EXPORT_SYMBOL(dm_table_get);
-EXPORT_SYMBOL(dm_table_unplug_all);
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index eaa3af0e063..d22b9905c16 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -807,8 +807,6 @@ void dm_requeue_unmapped_request(struct request *clone)
 	dm_unprep_request(rq);
 
 	spin_lock_irqsave(q->queue_lock, flags);
-	if (elv_queue_empty(q))
-		blk_plug_device(q);
 	blk_requeue_request(q, rq);
 	spin_unlock_irqrestore(q->queue_lock, flags);
 
@@ -1613,10 +1611,10 @@ static void dm_request_fn(struct request_queue *q)
 	 * number of in-flight I/Os after the queue is stopped in
 	 * dm_suspend().
 	 */
-	while (!blk_queue_plugged(q) && !blk_queue_stopped(q)) {
+	while (!blk_queue_stopped(q)) {
 		rq = blk_peek_request(q);
 		if (!rq)
-			goto plug_and_out;
+			goto delay_and_out;
 
 		/* always use block 0 to find the target for flushes for now */
 		pos = 0;
@@ -1627,7 +1625,7 @@ static void dm_request_fn(struct request_queue *q)
 		BUG_ON(!dm_target_is_valid(ti));
 
 		if (ti->type->busy && ti->type->busy(ti))
-			goto plug_and_out;
+			goto delay_and_out;
 
 		blk_start_request(rq);
 		clone = rq->special;
@@ -1647,11 +1645,8 @@ requeued:
 	BUG_ON(!irqs_disabled());
 	spin_lock(q->queue_lock);
 
-plug_and_out:
-	if (!elv_queue_empty(q))
-		/* Some requests still remain, retry later */
-		blk_plug_device(q);
-
+delay_and_out:
+	blk_delay_queue(q, HZ / 10);
 out:
 	dm_table_put(map);
 
@@ -1680,20 +1675,6 @@ static int dm_lld_busy(struct request_queue *q)
 	return r;
 }
 
-static void dm_unplug_all(struct request_queue *q)
-{
-	struct mapped_device *md = q->queuedata;
-	struct dm_table *map = dm_get_live_table(md);
-
-	if (map) {
-		if (dm_request_based(md))
-			generic_unplug_device(q);
-
-		dm_table_unplug_all(map);
-		dm_table_put(map);
-	}
-}
-
 static int dm_any_congested(void *congested_data, int bdi_bits)
 {
 	int r = bdi_bits;
@@ -1817,7 +1798,6 @@ static void dm_init_md_queue(struct mapped_device *md)
 	md->queue->backing_dev_info.congested_data = md;
 	blk_queue_make_request(md->queue, dm_request);
 	blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
-	md->queue->unplug_fn = dm_unplug_all;
 	blk_queue_merge_bvec(md->queue, dm_merge_bvec);
 	blk_queue_flush(md->queue, REQ_FLUSH | REQ_FUA);
 }
@@ -2263,8 +2243,6 @@ static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
 	int r = 0;
 	DECLARE_WAITQUEUE(wait, current);
 
-	dm_unplug_all(md->queue);
-
 	add_wait_queue(&md->wait, &wait);
 
 	while (1) {
@@ -2539,7 +2517,6 @@ int dm_resume(struct mapped_device *md)
 
 	clear_bit(DMF_SUSPENDED, &md->flags);
 
-	dm_table_unplug_all(map);
 	r = 0;
 out:
 	dm_table_put(map);
diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 8a2f767f26d..38861b5b9d9 100644
--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -87,22 +87,6 @@ static int linear_mergeable_bvec(struct request_queue *q,
 	return maxsectors << 9;
 }
 
-static void linear_unplug(struct request_queue *q)
-{
-	mddev_t *mddev = q->queuedata;
-	linear_conf_t *conf;
-	int i;
-
-	rcu_read_lock();
-	conf = rcu_dereference(mddev->private);
-
-	for (i=0; i < mddev->raid_disks; i++) {
-		struct request_queue *r_queue = bdev_get_queue(conf->disks[i].rdev->bdev);
-		blk_unplug(r_queue);
-	}
-	rcu_read_unlock();
-}
-
 static int linear_congested(void *data, int bits)
 {
 	mddev_t *mddev = data;
@@ -225,7 +209,6 @@ static int linear_run (mddev_t *mddev)
 	md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
 
 	blk_queue_merge_bvec(mddev->queue, linear_mergeable_bvec);
-	mddev->queue->unplug_fn = linear_unplug;
 	mddev->queue->backing_dev_info.congested_fn = linear_congested;
 	mddev->queue->backing_dev_info.congested_data = mddev;
 	md_integrity_register(mddev);
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 0cc30ecda4c..ca0d79c264b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4812,7 +4812,6 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
 		__md_stop_writes(mddev);
 		md_stop(mddev);
 		mddev->queue->merge_bvec_fn = NULL;
-		mddev->queue->unplug_fn = NULL;
 		mddev->queue->backing_dev_info.congested_fn = NULL;
 
 		/* tell userspace to handle 'inactive' */
@@ -6669,8 +6668,6 @@ EXPORT_SYMBOL_GPL(md_allow_write);
 
 void md_unplug(mddev_t *mddev)
 {
-	if (mddev->queue)
-		blk_unplug(mddev->queue);
 	if (mddev->plug)
 		mddev->plug->unplug_fn(mddev->plug);
 }
@@ -6853,7 +6850,6 @@ void md_do_sync(mddev_t *mddev)
 		     >= mddev->resync_max - mddev->curr_resync_completed
 			    )) {
 			/* time to update curr_resync_completed */
-			md_unplug(mddev);
 			wait_event(mddev->recovery_wait,
 				   atomic_read(&mddev->recovery_active) == 0);
 			mddev->curr_resync_completed = j;
@@ -6929,7 +6925,6 @@ void md_do_sync(mddev_t *mddev)
 		 * about not overloading the IO subsystem. (things like an
 		 * e2fsck being done on the RAID array should execute fast)
 		 */
-		md_unplug(mddev);
 		cond_resched();
 
 		currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
@@ -6948,8 +6943,6 @@ void md_do_sync(mddev_t *mddev)
 	 * this also signals 'finished resyncing' to md_stop
 	 */
  out:
-	md_unplug(mddev);
-
 	wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
 
 	/* tell personality that we are finished */
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 6d7ddf32ef2..1cc8ed44e4a 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -106,36 +106,6 @@ static void multipath_end_request(struct bio *bio, int error)
 	rdev_dec_pending(rdev, conf->mddev);
 }
 
-static void unplug_slaves(mddev_t *mddev)
-{
-	multipath_conf_t *conf = mddev->private;
-	int i;
-
-	rcu_read_lock();
-	for (i=0; i<mddev->raid_disks; i++) {
-		mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
-		if (rdev && !test_bit(Faulty, &rdev->flags)
-		    && atomic_read(&rdev->nr_pending)) {
-			struct request_queue *r_queue = bdev_get_queue(rdev->bdev);
-
-			atomic_inc(&rdev->nr_pending);
-			rcu_read_unlock();
-
-			blk_unplug(r_queue);
-
-			rdev_dec_pending(rdev, mddev);
-			rcu_read_lock();
-		}
-	}
-	rcu_read_unlock();
-}
-
-static void multipath_unplug(struct request_queue *q)
-{
-	unplug_slaves(q->queuedata);
-}
-
-
 static int multipath_make_request(mddev_t *mddev, struct bio * bio)
 {
 	multipath_conf_t *conf = mddev->private;
@@ -518,7 +488,6 @@ static int multipath_run (mddev_t *mddev)
 	 */
 	md_set_array_sectors(mddev, multipath_size(mddev, 0, 0));
 
-	mddev->queue->unplug_fn = multipath_unplug;
 	mddev->queue->backing_dev_info.congested_fn = multipath_congested;
 	mddev->queue->backing_dev_info.congested_data = mddev;
 	md_integrity_register(mddev);
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index 637a96855ed..6338c0fe620 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -25,21 +25,6 @@
 #include "raid0.h"
 #include "raid5.h"
 
-static void raid0_unplug(struct request_queue *q)
-{
-	mddev_t *mddev = q->queuedata;
-	raid0_conf_t *conf = mddev->private;
-	mdk_rdev_t **devlist = conf->devlist;
-	int raid_disks = conf->strip_zone[0].nb_dev;
-	int i;
-
-	for (i=0; i < raid_disks; i++) {
-		struct request_queue *r_queue = bdev_get_queue(devlist[i]->bdev);
-
-		blk_unplug(r_queue);
-	}
-}
-
 static int raid0_congested(void *data, int bits)
 {
 	mddev_t *mddev = data;
@@ -272,7 +257,6 @@ static int create_strip_zones(mddev_t *mddev, raid0_conf_t **private_conf)
 		       mdname(mddev),
 		       (unsigned long long)smallest->sectors);
 	}
-	mddev->queue->unplug_fn = raid0_unplug;
 	mddev->queue->backing_dev_info.congested_fn = raid0_congested;
 	mddev->queue->backing_dev_info.congested_data = mddev;
 
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index a23ffa397ba..b67d822d57a 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -52,23 +52,16 @@
 #define	NR_RAID1_BIOS 256
 
 
-static void unplug_slaves(mddev_t *mddev);
-
 static void allow_barrier(conf_t *conf);
 static void lower_barrier(conf_t *conf);
 
 static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
 {
 	struct pool_info *pi = data;
-	r1bio_t *r1_bio;
 	int size = offsetof(r1bio_t, bios[pi->raid_disks]);
 
 	/* allocate a r1bio with room for raid_disks entries in the bios array */
-	r1_bio = kzalloc(size, gfp_flags);
-	if (!r1_bio && pi->mddev)
-		unplug_slaves(pi->mddev);
-
-	return r1_bio;
+	return kzalloc(size, gfp_flags);
 }
 
 static void r1bio_pool_free(void *r1_bio, void *data)
@@ -91,10 +84,8 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
 	int i, j;
 
 	r1_bio = r1bio_pool_alloc(gfp_flags, pi);
-	if (!r1_bio) {
-		unplug_slaves(pi->mddev);
+	if (!r1_bio)
 		return NULL;
-	}
 
 	/*
 	 * Allocate bios : 1 for reading, n-1 for writing
@@ -520,37 +511,6 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
 	return new_disk;
 }
 
-static void unplug_slaves(mddev_t *mddev)
-{
-	conf_t *conf = mddev->private;
-	int i;
-
-	rcu_read_lock();
-	for (i=0; i<mddev->raid_disks; i++) {
-		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
-		if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) {
-			struct request_queue *r_queue = bdev_get_queue(rdev->bdev);
-
-			atomic_inc(&rdev->nr_pending);
-			rcu_read_unlock();
-
-			blk_unplug(r_queue);
-
-			rdev_dec_pending(rdev, mddev);
-			rcu_read_lock();
-		}
-	}
-	rcu_read_unlock();
-}
-
-static void raid1_unplug(struct request_queue *q)
-{
-	mddev_t *mddev = q->queuedata;
-
-	unplug_slaves(mddev);
-	md_wakeup_thread(mddev->thread);
-}
-
 static int raid1_congested(void *data, int bits)
 {
 	mddev_t *mddev = data;
@@ -580,20 +540,16 @@ static int raid1_congested(void *data, int bits)
 }
 
 
-static int flush_pending_writes(conf_t *conf)
+static void flush_pending_writes(conf_t *conf)
 {
 	/* Any writes that have been queued but are awaiting
 	 * bitmap updates get flushed here.
-	 * We return 1 if any requests were actually submitted.
 	 */
-	int rv = 0;
-
 	spin_lock_irq(&conf->device_lock);
 
 	if (conf->pending_bio_list.head) {
 		struct bio *bio;
 		bio = bio_list_get(&conf->pending_bio_list);
-		blk_remove_plug(conf->mddev->queue);
 		spin_unlock_irq(&conf->device_lock);
 		/* flush any pending bitmap writes to
 		 * disk before proceeding w/ I/O */
@@ -605,10 +561,14 @@ static int flush_pending_writes(conf_t *conf)
 			generic_make_request(bio);
 			bio = next;
 		}
-		rv = 1;
 	} else
 		spin_unlock_irq(&conf->device_lock);
-	return rv;
+}
+
+static void md_kick_device(mddev_t *mddev)
+{
+	blk_flush_plug(current);
+	md_wakeup_thread(mddev->thread);
 }
 
 /* Barriers....
@@ -640,8 +600,7 @@ static void raise_barrier(conf_t *conf)
 
 	/* Wait until no block IO is waiting */
 	wait_event_lock_irq(conf->wait_barrier, !conf->nr_waiting,
-			    conf->resync_lock,
-			    raid1_unplug(conf->mddev->queue));
+			    conf->resync_lock, md_kick_device(conf->mddev));
 
 	/* block any new IO from starting */
 	conf->barrier++;
@@ -649,8 +608,7 @@ static void raise_barrier(conf_t *conf)
 	/* Now wait for all pending IO to complete */
 	wait_event_lock_irq(conf->wait_barrier,
 			    !conf->nr_pending && conf->barrier < RESYNC_DEPTH,
-			    conf->resync_lock,
-			    raid1_unplug(conf->mddev->queue));
+			    conf->resync_lock, md_kick_device(conf->mddev));
 
 	spin_unlock_irq(&conf->resync_lock);
 }
@@ -672,7 +630,7 @@ static void wait_barrier(conf_t *conf)
 		conf->nr_waiting++;
 		wait_event_lock_irq(conf->wait_barrier, !conf->barrier,
 				    conf->resync_lock,
-				    raid1_unplug(conf->mddev->queue));
+				    md_kick_device(conf->mddev));
 		conf->nr_waiting--;
 	}
 	conf->nr_pending++;
@@ -709,7 +667,7 @@ static void freeze_array(conf_t *conf)
 			    conf->nr_pending == conf->nr_queued+1,
 			    conf->resync_lock,
 			    ({ flush_pending_writes(conf);
-			       raid1_unplug(conf->mddev->queue); }));
+			       md_kick_device(conf->mddev); }));
 	spin_unlock_irq(&conf->resync_lock);
 }
 static void unfreeze_array(conf_t *conf)
@@ -959,7 +917,6 @@ static int make_request(mddev_t *mddev, struct bio * bio)
 		atomic_inc(&r1_bio->remaining);
 		spin_lock_irqsave(&conf->device_lock, flags);
 		bio_list_add(&conf->pending_bio_list, mbio);
-		blk_plug_device(mddev->queue);
 		spin_unlock_irqrestore(&conf->device_lock, flags);
 	}
 	r1_bio_write_done(r1_bio, bio->bi_vcnt, behind_pages, behind_pages != NULL);
@@ -968,7 +925,7 @@ static int make_request(mddev_t *mddev, struct bio * bio)
 	/* In case raid1d snuck in to freeze_array */
 	wake_up(&conf->wait_barrier);
 
-	if (do_sync)
+	if (do_sync || !bitmap)
 		md_wakeup_thread(mddev->thread);
 
 	return 0;
@@ -1558,7 +1515,6 @@ static void raid1d(mddev_t *mddev)
 	unsigned long flags;
 	conf_t *conf = mddev->private;
 	struct list_head *head = &conf->retry_list;
-	int unplug=0;
 	mdk_rdev_t *rdev;
 
 	md_check_recovery(mddev);
@@ -1566,7 +1522,7 @@ static void raid1d(mddev_t *mddev)
 	for (;;) {
 		char b[BDEVNAME_SIZE];
 
-		unplug += flush_pending_writes(conf);
+		flush_pending_writes(conf);
 
 		spin_lock_irqsave(&conf->device_lock, flags);
 		if (list_empty(head)) {
@@ -1580,10 +1536,9 @@ static void raid1d(mddev_t *mddev)
 
 		mddev = r1_bio->mddev;
 		conf = mddev->private;
-		if (test_bit(R1BIO_IsSync, &r1_bio->state)) {
+		if (test_bit(R1BIO_IsSync, &r1_bio->state))
 			sync_request_write(mddev, r1_bio);
-			unplug = 1;
-		} else {
+		else {
 			int disk;
 
 			/* we got a read error. Maybe the drive is bad.  Maybe just
@@ -1633,14 +1588,11 @@ static void raid1d(mddev_t *mddev)
 				bio->bi_end_io = raid1_end_read_request;
 				bio->bi_rw = READ | do_sync;
 				bio->bi_private = r1_bio;
-				unplug = 1;
 				generic_make_request(bio);
 			}
 		}
 		cond_resched();
 	}
-	if (unplug)
-		unplug_slaves(mddev);
 }
 
 
@@ -2064,7 +2016,6 @@ static int run(mddev_t *mddev)
 
 	md_set_array_sectors(mddev, raid1_size(mddev, 0, 0));
 
-	mddev->queue->unplug_fn = raid1_unplug;
 	mddev->queue->backing_dev_info.congested_fn = raid1_congested;
 	mddev->queue->backing_dev_info.congested_data = mddev;
 	md_integrity_register(mddev);
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 3b607b28741..e79f1c5bf71 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -57,23 +57,16 @@
  */
 #define	NR_RAID10_BIOS 256
 
-static void unplug_slaves(mddev_t *mddev);
-
 static void allow_barrier(conf_t *conf);
 static void lower_barrier(conf_t *conf);
 
 static void * r10bio_pool_alloc(gfp_t gfp_flags, void *data)
 {
 	conf_t *conf = data;
-	r10bio_t *r10_bio;
 	int size = offsetof(struct r10bio_s, devs[conf->copies]);
 
 	/* allocate a r10bio with room for raid_disks entries in the bios array */
-	r10_bio = kzalloc(size, gfp_flags);
-	if (!r10_bio && conf->mddev)
-		unplug_slaves(conf->mddev);
-
-	return r10_bio;
+	return kzalloc(size, gfp_flags);
 }
 
 static void r10bio_pool_free(void *r10_bio, void *data)
@@ -106,10 +99,8 @@ static void * r10buf_pool_alloc(gfp_t gfp_flags, void *data)
 	int nalloc;
 
 	r10_bio = r10bio_pool_alloc(gfp_flags, conf);
-	if (!r10_bio) {
-		unplug_slaves(conf->mddev);
+	if (!r10_bio)
 		return NULL;
-	}
 
 	if (test_bit(MD_RECOVERY_SYNC, &conf->mddev->recovery))
 		nalloc = conf->copies; /* resync */
@@ -597,37 +588,6 @@ rb_out:
 	return disk;
 }
 
-static void unplug_slaves(mddev_t *mddev)
-{
-	conf_t *conf = mddev->private;
-	int i;
-
-	rcu_read_lock();
-	for (i=0; i < conf->raid_disks; i++) {
-		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
-		if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) {
-			struct request_queue *r_queue = bdev_get_queue(rdev->bdev);
-
-			atomic_inc(&rdev->nr_pending);
-			rcu_read_unlock();
-
-			blk_unplug(r_queue);
-
-			rdev_dec_pending(rdev, mddev);
-			rcu_read_lock();
-		}
-	}
-	rcu_read_unlock();
-}
-
-static void raid10_unplug(struct request_queue *q)
-{
-	mddev_t *mddev = q->queuedata;
-
-	unplug_slaves(q->queuedata);
-	md_wakeup_thread(mddev->thread);
-}
-
 static int raid10_congested(void *data, int bits)
 {
 	mddev_t *mddev = data;
@@ -649,20 +609,16 @@ static int raid10_congested(void *data, int bits)
 	return ret;
 }
 
-static int flush_pending_writes(conf_t *conf)
+static void flush_pending_writes(conf_t *conf)
 {
 	/* Any writes that have been queued but are awaiting
 	 * bitmap updates get flushed here.
-	 * We return 1 if any requests were actually submitted.
 	 */
-	int rv = 0;
-
 	spin_lock_irq(&conf->device_lock);
 
 	if (conf->pending_bio_list.head) {
 		struct bio *bio;
 		bio = bio_list_get(&conf->pending_bio_list);
-		blk_remove_plug(conf->mddev->queue);
 		spin_unlock_irq(&conf->device_lock);
 		/* flush any pending bitmap writes to disk
 		 * before proceeding w/ I/O */
@@ -674,11 +630,16 @@ static int flush_pending_writes(conf_t *conf)
 			generic_make_request(bio);
 			bio = next;
 		}
-		rv = 1;
 	} else
 		spin_unlock_irq(&conf->device_lock);
-	return rv;
 }
+
+static void md_kick_device(mddev_t *mddev)
+{
+	blk_flush_plug(current);
+	md_wakeup_thread(mddev->thread);
+}
+
 /* Barriers....
  * Sometimes we need to suspend IO while we do something else,
  * either some resync/recovery, or reconfigure the array.
@@ -708,8 +669,7 @@ static void raise_barrier(conf_t *conf, int force)
 
 	/* Wait until no block IO is waiting (unless 'force') */
 	wait_event_lock_irq(conf->wait_barrier, force || !conf->nr_waiting,
-			    conf->resync_lock,
-			    raid10_unplug(conf->mddev->queue));
+			    conf->resync_lock, md_kick_device(conf->mddev));
 
 	/* block any new IO from starting */
 	conf->barrier++;
@@ -717,8 +677,7 @@ static void raise_barrier(conf_t *conf, int force)
 	/* No wait for all pending IO to complete */
 	wait_event_lock_irq(conf->wait_barrier,
 			    !conf->nr_pending && conf->barrier < RESYNC_DEPTH,
-			    conf->resync_lock,
-			    raid10_unplug(conf->mddev->queue));
+			    conf->resync_lock, md_kick_device(conf->mddev));
 
 	spin_unlock_irq(&conf->resync_lock);
 }
@@ -739,7 +698,7 @@ static void wait_barrier(conf_t *conf)
 		conf->nr_waiting++;
 		wait_event_lock_irq(conf->wait_barrier, !conf->barrier,
 				    conf->resync_lock,
-				    raid10_unplug(conf->mddev->queue));
+				    md_kick_device(conf->mddev));
 		conf->nr_waiting--;
 	}
 	conf->nr_pending++;
@@ -776,7 +735,7 @@ static void freeze_array(conf_t *conf)
 			    conf->nr_pending == conf->nr_queued+1,
 			    conf->resync_lock,
 			    ({ flush_pending_writes(conf);
-			       raid10_unplug(conf->mddev->queue); }));
+			       md_kick_device(conf->mddev); }));
 	spin_unlock_irq(&conf->resync_lock);
 }
 
@@ -971,7 +930,6 @@ static int make_request(mddev_t *mddev, struct bio * bio)
 		atomic_inc(&r10_bio->remaining);
 		spin_lock_irqsave(&conf->device_lock, flags);
 		bio_list_add(&conf->pending_bio_list, mbio);
-		blk_plug_device(mddev->queue);
 		spin_unlock_irqrestore(&conf->device_lock, flags);
 	}
 
@@ -988,7 +946,7 @@ static int make_request(mddev_t *mddev, struct bio * bio)
 	/* In case raid10d snuck in to freeze_array */
 	wake_up(&conf->wait_barrier);
 
-	if (do_sync)
+	if (do_sync || !mddev->bitmap)
 		md_wakeup_thread(mddev->thread);
 
 	return 0;
@@ -1681,7 +1639,6 @@ static void raid10d(mddev_t *mddev)
 	unsigned long flags;
 	conf_t *conf = mddev->private;
 	struct list_head *head = &conf->retry_list;
-	int unplug=0;
 	mdk_rdev_t *rdev;
 
 	md_check_recovery(mddev);
@@ -1689,7 +1646,7 @@ static void raid10d(mddev_t *mddev)
 	for (;;) {
 		char b[BDEVNAME_SIZE];
 
-		unplug += flush_pending_writes(conf);
+		flush_pending_writes(conf);
 
 		spin_lock_irqsave(&conf->device_lock, flags);
 		if (list_empty(head)) {
@@ -1703,13 +1660,11 @@ static void raid10d(mddev_t *mddev)
 
 		mddev = r10_bio->mddev;
 		conf = mddev->private;
-		if (test_bit(R10BIO_IsSync, &r10_bio->state)) {
+		if (test_bit(R10BIO_IsSync, &r10_bio->state))
 			sync_request_write(mddev, r10_bio);
-			unplug = 1;
-		} else 	if (test_bit(R10BIO_IsRecover, &r10_bio->state)) {
+		else if (test_bit(R10BIO_IsRecover, &r10_bio->state))
 			recovery_request_write(mddev, r10_bio);
-			unplug = 1;
-		} else {
+		else {
 			int mirror;
 			/* we got a read error. Maybe the drive is bad.  Maybe just
 			 * the block and we can fix it.
@@ -1756,14 +1711,11 @@ static void raid10d(mddev_t *mddev)
 				bio->bi_rw = READ | do_sync;
 				bio->bi_private = r10_bio;
 				bio->bi_end_io = raid10_end_read_request;
-				unplug = 1;
 				generic_make_request(bio);
 			}
 		}
 		cond_resched();
 	}
-	if (unplug)
-		unplug_slaves(mddev);
 }
 
 
@@ -2376,7 +2328,6 @@ static int run(mddev_t *mddev)
 	md_set_array_sectors(mddev, size);
 	mddev->resync_max_sectors = size;
 
-	mddev->queue->unplug_fn = raid10_unplug;
 	mddev->queue->backing_dev_info.congested_fn = raid10_congested;
 	mddev->queue->backing_dev_info.congested_data = mddev;
 
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 70281282419..e867ee42b15 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -433,8 +433,6 @@ static int has_failed(raid5_conf_t *conf)
 	return 0;
 }
 
-static void unplug_slaves(mddev_t *mddev);
-
 static struct stripe_head *
 get_active_stripe(raid5_conf_t *conf, sector_t sector,
 		  int previous, int noblock, int noquiesce)
@@ -463,8 +461,7 @@ get_active_stripe(raid5_conf_t *conf, sector_t sector,
 						     < (conf->max_nr_stripes *3/4)
 						     || !conf->inactive_blocked),
 						    conf->device_lock,
-						    md_raid5_unplug_device(conf)
-					);
+						    md_raid5_kick_device(conf));
 				conf->inactive_blocked = 0;
 			} else
 				init_stripe(sh, sector, previous);
@@ -1473,8 +1470,7 @@ static int resize_stripes(raid5_conf_t *conf, int newsize)
 		wait_event_lock_irq(conf->wait_for_stripe,
 				    !list_empty(&conf->inactive_list),
 				    conf->device_lock,
-				    unplug_slaves(conf->mddev)
-			);
+				    blk_flush_plug(current));
 		osh = get_free_stripe(conf);
 		spin_unlock_irq(&conf->device_lock);
 		atomic_set(&nsh->count, 1);
@@ -3645,58 +3641,19 @@ static void activate_bit_delay(raid5_conf_t *conf)
 	}
 }
 
-static void unplug_slaves(mddev_t *mddev)
+void md_raid5_kick_device(raid5_conf_t *conf)
 {
-	raid5_conf_t *conf = mddev->private;
-	int i;
-	int devs = max(conf->raid_disks, conf->previous_raid_disks);
-
-	rcu_read_lock();
-	for (i = 0; i < devs; i++) {
-		mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev);
-		if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) {
-			struct request_queue *r_queue = bdev_get_queue(rdev->bdev);
-
-			atomic_inc(&rdev->nr_pending);
-			rcu_read_unlock();
-
-			blk_unplug(r_queue);
-
-			rdev_dec_pending(rdev, mddev);
-			rcu_read_lock();
-		}
-	}
-	rcu_read_unlock();
-}
-
-void md_raid5_unplug_device(raid5_conf_t *conf)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&conf->device_lock, flags);
-
-	if (plugger_remove_plug(&conf->plug)) {
-		conf->seq_flush++;
-		raid5_activate_delayed(conf);
-	}
+	blk_flush_plug(current);
+	raid5_activate_delayed(conf);
 	md_wakeup_thread(conf->mddev->thread);
-
-	spin_unlock_irqrestore(&conf->device_lock, flags);
-
-	unplug_slaves(conf->mddev);
 }
-EXPORT_SYMBOL_GPL(md_raid5_unplug_device);
+EXPORT_SYMBOL_GPL(md_raid5_kick_device);
 
 static void raid5_unplug(struct plug_handle *plug)
 {
 	raid5_conf_t *conf = container_of(plug, raid5_conf_t, plug);
-	md_raid5_unplug_device(conf);
-}
 
-static void raid5_unplug_queue(struct request_queue *q)
-{
-	mddev_t *mddev = q->queuedata;
-	md_raid5_unplug_device(mddev->private);
+	md_raid5_kick_device(conf);
 }
 
 int md_raid5_congested(mddev_t *mddev, int bits)
@@ -4100,7 +4057,7 @@ static int make_request(mddev_t *mddev, struct bio * bi)
 				 * add failed due to overlap.  Flush everything
 				 * and wait a while
 				 */
-				md_raid5_unplug_device(conf);
+				md_raid5_kick_device(conf);
 				release_stripe(sh);
 				schedule();
 				goto retry;
@@ -4365,7 +4322,6 @@ static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *ski
 
 	if (sector_nr >= max_sector) {
 		/* just being told to finish up .. nothing much to do */
-		unplug_slaves(mddev);
 
 		if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
 			end_reshape(conf);
@@ -4569,7 +4525,6 @@ static void raid5d(mddev_t *mddev)
 	spin_unlock_irq(&conf->device_lock);
 
 	async_tx_issue_pending_all();
-	unplug_slaves(mddev);
 
 	pr_debug("--- raid5d inactive\n");
 }
@@ -5205,7 +5160,6 @@ static int run(mddev_t *mddev)
 		mddev->queue->backing_dev_info.congested_data = mddev;
 		mddev->queue->backing_dev_info.congested_fn = raid5_congested;
 		mddev->queue->queue_lock = &conf->device_lock;
-		mddev->queue->unplug_fn = raid5_unplug_queue;
 
 		chunk_size = mddev->chunk_sectors << 9;
 		blk_queue_io_min(mddev->queue, chunk_size);
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 2ace0582b40..8d563a4f022 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -503,6 +503,6 @@ static inline int algorithm_is_DDF(int layout)
 }
 
 extern int md_raid5_congested(mddev_t *mddev, int bits);
-extern void md_raid5_unplug_device(raid5_conf_t *conf);
+extern void md_raid5_kick_device(raid5_conf_t *conf);
 extern int raid5_set_cache_size(mddev_t *mddev, int size);
 #endif
diff --git a/drivers/message/i2o/i2o_block.c b/drivers/message/i2o/i2o_block.c
index ae7cad18589..b29eb4eaa86 100644
--- a/drivers/message/i2o/i2o_block.c
+++ b/drivers/message/i2o/i2o_block.c
@@ -895,11 +895,7 @@ static void i2o_block_request_fn(struct request_queue *q)
 {
 	struct request *req;
 
-	while (!blk_queue_plugged(q)) {
-		req = blk_peek_request(q);
-		if (!req)
-			break;
-
+	while ((req = blk_peek_request(q)) != NULL) {
 		if (req->cmd_type == REQ_TYPE_FS) {
 			struct i2o_block_delayed_request *dreq;
 			struct i2o_block_request *ireq = req->special;
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index 4e42d030e09..2ae727568df 100644
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -55,8 +55,7 @@ static int mmc_queue_thread(void *d)
 
 		spin_lock_irq(q->queue_lock);
 		set_current_state(TASK_INTERRUPTIBLE);
-		if (!blk_queue_plugged(q))
-			req = blk_fetch_request(q);
+		req = blk_fetch_request(q);
 		mq->req = req;
 		spin_unlock_irq(q->queue_lock);
 
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 794bfd96226..4d2df2f76ea 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -1917,7 +1917,7 @@ static void __dasd_process_request_queue(struct dasd_block *block)
 		return;
 	}
 	/* Now we try to fetch requests from the request queue */
-	while (!blk_queue_plugged(queue) && (req = blk_peek_request(queue))) {
+	while ((req = blk_peek_request(queue))) {
 		if (basedev->features & DASD_FEATURE_READONLY &&
 		    rq_data_dir(req) == WRITE) {
 			DBF_DEV_EVENT(DBF_ERR, basedev,
diff --git a/drivers/s390/char/tape_block.c b/drivers/s390/char/tape_block.c
index 55d2d0f4eab..f061b2527b4 100644
--- a/drivers/s390/char/tape_block.c
+++ b/drivers/s390/char/tape_block.c
@@ -161,7 +161,6 @@ tapeblock_requeue(struct work_struct *work) {
 
 	spin_lock_irq(&device->blk_data.request_queue_lock);
 	while (
-		!blk_queue_plugged(queue) &&
 		blk_peek_request(queue) &&
 		nr_queued < TAPEBLOCK_MIN_REQUEUE
 	) {
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
index 998c01be323..2cefabd5bdb 100644
--- a/drivers/scsi/scsi_transport_fc.c
+++ b/drivers/scsi/scsi_transport_fc.c
@@ -3913,7 +3913,7 @@ fc_bsg_request_handler(struct request_queue *q, struct Scsi_Host *shost,
 	if (!get_device(dev))
 		return;
 
-	while (!blk_queue_plugged(q)) {
+	while (1) {
 		if (rport && (rport->port_state == FC_PORTSTATE_BLOCKED) &&
 		    !(rport->flags & FC_RPORT_FAST_FAIL_TIMEDOUT))
 			break;
diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c
index 927e99cb722..c6fcf76cade 100644
--- a/drivers/scsi/scsi_transport_sas.c
+++ b/drivers/scsi/scsi_transport_sas.c
@@ -173,11 +173,7 @@ static void sas_smp_request(struct request_queue *q, struct Scsi_Host *shost,
 	int ret;
 	int (*handler)(struct Scsi_Host *, struct sas_rphy *, struct request *);
 
-	while (!blk_queue_plugged(q)) {
-		req = blk_fetch_request(q);
-		if (!req)
-			break;
-
+	while ((req = blk_fetch_request(q)) != NULL) {
 		spin_unlock_irq(q->queue_lock);
 
 		handler = to_sas_internal(shost->transportt)->f->smp_handler;
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 67f0c09983c..c1b539d7b0d 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -392,9 +392,8 @@ static int iblock_do_task(struct se_task *task)
 {
 	struct se_device *dev = task->task_se_cmd->se_dev;
 	struct iblock_req *req = IBLOCK_REQ(task);
-	struct iblock_dev *ibd = (struct iblock_dev *)req->ib_dev;
-	struct request_queue *q = bdev_get_queue(ibd->ibd_bd);
 	struct bio *bio = req->ib_bio, *nbio = NULL;
+	struct blk_plug plug;
 	int rw;
 
 	if (task->task_data_direction == DMA_TO_DEVICE) {
@@ -412,6 +411,7 @@ static int iblock_do_task(struct se_task *task)
 		rw = READ;
 	}
 
+	blk_start_plug(&plug);
 	while (bio) {
 		nbio = bio->bi_next;
 		bio->bi_next = NULL;
@@ -421,9 +421,8 @@ static int iblock_do_task(struct se_task *task)
 		submit_bio(rw, bio);
 		bio = nbio;
 	}
+	blk_finish_plug(&plug);
 
-	if (q->unplug_fn)
-		q->unplug_fn(q);
 	return PYX_TRANSPORT_SENT_TO_TRANSPORT;
 }
 
diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c
index 65794b8fe79..1cc84b27613 100644
--- a/fs/adfs/inode.c
+++ b/fs/adfs/inode.c
@@ -73,7 +73,6 @@ static sector_t _adfs_bmap(struct address_space *mapping, sector_t block)
 static const struct address_space_operations adfs_aops = {
 	.readpage	= adfs_readpage,
 	.writepage	= adfs_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= adfs_write_begin,
 	.write_end	= generic_write_end,
 	.bmap		= _adfs_bmap
diff --git a/fs/affs/file.c b/fs/affs/file.c
index 0a90dcd46de..acf321b70fc 100644
--- a/fs/affs/file.c
+++ b/fs/affs/file.c
@@ -429,7 +429,6 @@ static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
 const struct address_space_operations affs_aops = {
 	.readpage = affs_readpage,
 	.writepage = affs_writepage,
-	.sync_page = block_sync_page,
 	.write_begin = affs_write_begin,
 	.write_end = generic_write_end,
 	.bmap = _affs_bmap
@@ -786,7 +785,6 @@ out:
 const struct address_space_operations affs_aops_ofs = {
 	.readpage = affs_readpage_ofs,
 	//.writepage = affs_writepage_ofs,
-	//.sync_page = affs_sync_page_ofs,
 	.write_begin = affs_write_begin_ofs,
 	.write_end = affs_write_end_ofs
 };
diff --git a/fs/aio.c b/fs/aio.c
index fc557a3be0a..c5ea494ea9e 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1550,9 +1550,11 @@ static void aio_batch_free(struct hlist_head *batch_hash)
 	struct hlist_node *pos, *n;
 	int i;
 
+	/*
+	 * TODO: kill this
+	 */
 	for (i = 0; i < AIO_BATCH_HASH_SIZE; i++) {
 		hlist_for_each_entry_safe(abe, pos, n, &batch_hash[i], list) {
-			blk_run_address_space(abe->mapping);
 			iput(abe->mapping->host);
 			hlist_del(&abe->list);
 			mempool_free(abe, abe_pool);
diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c
index b1d0c794747..06457ed8f3e 100644
--- a/fs/befs/linuxvfs.c
+++ b/fs/befs/linuxvfs.c
@@ -75,7 +75,6 @@ static const struct inode_operations befs_dir_inode_operations = {
 
 static const struct address_space_operations befs_aops = {
 	.readpage	= befs_readpage,
-	.sync_page	= block_sync_page,
 	.bmap		= befs_bmap,
 };
 
diff --git a/fs/bfs/file.c b/fs/bfs/file.c
index eb67edd0f8e..f20e8a71062 100644
--- a/fs/bfs/file.c
+++ b/fs/bfs/file.c
@@ -186,7 +186,6 @@ static sector_t bfs_bmap(struct address_space *mapping, sector_t block)
 const struct address_space_operations bfs_aops = {
 	.readpage	= bfs_readpage,
 	.writepage	= bfs_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= bfs_write_begin,
 	.write_end	= generic_write_end,
 	.bmap		= bfs_bmap,
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 4fb8a343153..fffc2c67239 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1520,7 +1520,6 @@ static int blkdev_releasepage(struct page *page, gfp_t wait)
 static const struct address_space_operations def_blk_aops = {
 	.readpage	= blkdev_readpage,
 	.writepage	= blkdev_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= blkdev_write_begin,
 	.write_end	= blkdev_write_end,
 	.writepages	= generic_writepages,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index e1aa8d607bc..ada1f6bd0a5 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -847,7 +847,6 @@ static const struct address_space_operations btree_aops = {
 	.writepages	= btree_writepages,
 	.releasepage	= btree_releasepage,
 	.invalidatepage = btree_invalidatepage,
-	.sync_page	= block_sync_page,
 #ifdef CONFIG_MIGRATION
 	.migratepage	= btree_migratepage,
 #endif
@@ -1330,82 +1329,6 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 	return ret;
 }
 
-/*
- * this unplugs every device on the box, and it is only used when page
- * is null
- */
-static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-	struct btrfs_device *device;
-	struct btrfs_fs_info *info;
-
-	info = (struct btrfs_fs_info *)bdi->unplug_io_data;
-	list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
-		if (!device->bdev)
-			continue;
-
-		bdi = blk_get_backing_dev_info(device->bdev);
-		if (bdi->unplug_io_fn)
-			bdi->unplug_io_fn(bdi, page);
-	}
-}
-
-static void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-	struct inode *inode;
-	struct extent_map_tree *em_tree;
-	struct extent_map *em;
-	struct address_space *mapping;
-	u64 offset;
-
-	/* the generic O_DIRECT read code does this */
-	if (1 || !page) {
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-
-	/*
-	 * page->mapping may change at any time.  Get a consistent copy
-	 * and use that for everything below
-	 */
-	smp_mb();
-	mapping = page->mapping;
-	if (!mapping)
-		return;
-
-	inode = mapping->host;
-
-	/*
-	 * don't do the expensive searching for a small number of
-	 * devices
-	 */
-	if (BTRFS_I(inode)->root->fs_info->fs_devices->open_devices <= 2) {
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-
-	offset = page_offset(page);
-
-	em_tree = &BTRFS_I(inode)->extent_tree;
-	read_lock(&em_tree->lock);
-	em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
-	read_unlock(&em_tree->lock);
-	if (!em) {
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-
-	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
-		free_extent_map(em);
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-	offset = offset - em->start;
-	btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree,
-			  em->block_start + offset, page);
-	free_extent_map(em);
-}
-
 /*
  * If this fails, caller must call bdi_destroy() to get rid of the
  * bdi again.
@@ -1420,8 +1343,6 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
 		return err;
 
 	bdi->ra_pages	= default_backing_dev_info.ra_pages;
-	bdi->unplug_io_fn	= btrfs_unplug_io_fn;
-	bdi->unplug_io_data	= info;
 	bdi->congested_fn	= btrfs_congested_fn;
 	bdi->congested_data	= info;
 	return 0;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index fb9bd7832b6..462e08e724b 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7218,7 +7218,6 @@ static const struct address_space_operations btrfs_aops = {
 	.writepage	= btrfs_writepage,
 	.writepages	= btrfs_writepages,
 	.readpages	= btrfs_readpages,
-	.sync_page	= block_sync_page,
 	.direct_IO	= btrfs_direct_IO,
 	.invalidatepage = btrfs_invalidatepage,
 	.releasepage	= btrfs_releasepage,
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index af7dbca1527..6e0e82a1b18 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -162,7 +162,6 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
 	struct bio *cur;
 	int again = 0;
 	unsigned long num_run;
-	unsigned long num_sync_run;
 	unsigned long batch_run = 0;
 	unsigned long limit;
 	unsigned long last_waited = 0;
@@ -173,11 +172,6 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
 	limit = btrfs_async_submit_limit(fs_info);
 	limit = limit * 2 / 3;
 
-	/* we want to make sure that every time we switch from the sync
-	 * list to the normal list, we unplug
-	 */
-	num_sync_run = 0;
-
 loop:
 	spin_lock(&device->io_lock);
 
@@ -223,15 +217,6 @@ loop_lock:
 
 	spin_unlock(&device->io_lock);
 
-	/*
-	 * if we're doing the regular priority list, make sure we unplug
-	 * for any high prio bios we've sent down
-	 */
-	if (pending_bios == &device->pending_bios && num_sync_run > 0) {
-		num_sync_run = 0;
-		blk_run_backing_dev(bdi, NULL);
-	}
-
 	while (pending) {
 
 		rmb();
@@ -259,19 +244,11 @@ loop_lock:
 
 		BUG_ON(atomic_read(&cur->bi_cnt) == 0);
 
-		if (cur->bi_rw & REQ_SYNC)
-			num_sync_run++;
-
 		submit_bio(cur->bi_rw, cur);
 		num_run++;
 		batch_run++;
-		if (need_resched()) {
-			if (num_sync_run) {
-				blk_run_backing_dev(bdi, NULL);
-				num_sync_run = 0;
-			}
+		if (need_resched())
 			cond_resched();
-		}
 
 		/*
 		 * we made progress, there is more work to do and the bdi
@@ -304,13 +281,8 @@ loop_lock:
 				 * against it before looping
 				 */
 				last_waited = ioc->last_waited;
-				if (need_resched()) {
-					if (num_sync_run) {
-						blk_run_backing_dev(bdi, NULL);
-						num_sync_run = 0;
-					}
+				if (need_resched())
 					cond_resched();
-				}
 				continue;
 			}
 			spin_lock(&device->io_lock);
@@ -323,22 +295,6 @@ loop_lock:
 		}
 	}
 
-	if (num_sync_run) {
-		num_sync_run = 0;
-		blk_run_backing_dev(bdi, NULL);
-	}
-	/*
-	 * IO has already been through a long path to get here.  Checksumming,
-	 * async helper threads, perhaps compression.  We've done a pretty
-	 * good job of collecting a batch of IO and should just unplug
-	 * the device right away.
-	 *
-	 * This will help anyone who is waiting on the IO, they might have
-	 * already unplugged, but managed to do so before the bio they
-	 * cared about found its way down here.
-	 */
-	blk_run_backing_dev(bdi, NULL);
-
 	cond_resched();
 	if (again)
 		goto loop;
@@ -2948,7 +2904,7 @@ static int find_live_mirror(struct map_lookup *map, int first, int num,
 static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
 			     u64 logical, u64 *length,
 			     struct btrfs_multi_bio **multi_ret,
-			     int mirror_num, struct page *unplug_page)
+			     int mirror_num)
 {
 	struct extent_map *em;
 	struct map_lookup *map;
@@ -2980,11 +2936,6 @@ again:
 	em = lookup_extent_mapping(em_tree, logical, *length);
 	read_unlock(&em_tree->lock);
 
-	if (!em && unplug_page) {
-		kfree(multi);
-		return 0;
-	}
-
 	if (!em) {
 		printk(KERN_CRIT "unable to find logical %llu len %llu\n",
 		       (unsigned long long)logical,
@@ -3040,13 +2991,13 @@ again:
 		*length = em->len - offset;
 	}
 
-	if (!multi_ret && !unplug_page)
+	if (!multi_ret)
 		goto out;
 
 	num_stripes = 1;
 	stripe_index = 0;
 	if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
-		if (unplug_page || (rw & REQ_WRITE))
+		if (rw & REQ_WRITE)
 			num_stripes = map->num_stripes;
 		else if (mirror_num)
 			stripe_index = mirror_num - 1;
@@ -3068,7 +3019,7 @@ again:
 		stripe_index = do_div(stripe_nr, factor);
 		stripe_index *= map->sub_stripes;
 
-		if (unplug_page || (rw & REQ_WRITE))
+		if (rw & REQ_WRITE)
 			num_stripes = map->sub_stripes;
 		else if (mirror_num)
 			stripe_index += mirror_num - 1;
@@ -3088,22 +3039,10 @@ again:
 	BUG_ON(stripe_index >= map->num_stripes);
 
 	for (i = 0; i < num_stripes; i++) {
-		if (unplug_page) {
-			struct btrfs_device *device;
-			struct backing_dev_info *bdi;
-
-			device = map->stripes[stripe_index].dev;
-			if (device->bdev) {
-				bdi = blk_get_backing_dev_info(device->bdev);
-				if (bdi->unplug_io_fn)
-					bdi->unplug_io_fn(bdi, unplug_page);
-			}
-		} else {
-			multi->stripes[i].physical =
-				map->stripes[stripe_index].physical +
-				stripe_offset + stripe_nr * map->stripe_len;
-			multi->stripes[i].dev = map->stripes[stripe_index].dev;
-		}
+		multi->stripes[i].physical =
+			map->stripes[stripe_index].physical +
+			stripe_offset + stripe_nr * map->stripe_len;
+		multi->stripes[i].dev = map->stripes[stripe_index].dev;
 		stripe_index++;
 	}
 	if (multi_ret) {
@@ -3121,7 +3060,7 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
 		      struct btrfs_multi_bio **multi_ret, int mirror_num)
 {
 	return __btrfs_map_block(map_tree, rw, logical, length, multi_ret,
-				 mirror_num, NULL);
+				 mirror_num);
 }
 
 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
@@ -3189,14 +3128,6 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 	return 0;
 }
 
-int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
-		      u64 logical, struct page *page)
-{
-	u64 length = PAGE_CACHE_SIZE;
-	return __btrfs_map_block(map_tree, READ, logical, &length,
-				 NULL, 0, page);
-}
-
 static void end_bio_multi_stripe(struct bio *bio, int err)
 {
 	struct btrfs_multi_bio *multi = bio->bi_private;
diff --git a/fs/buffer.c b/fs/buffer.c
index 2219a76e2ca..f903f2e5b4f 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -54,23 +54,15 @@ init_buffer(struct buffer_head *bh, bh_end_io_t *handler, void *private)
 }
 EXPORT_SYMBOL(init_buffer);
 
-static int sync_buffer(void *word)
+static int sleep_on_buffer(void *word)
 {
-	struct block_device *bd;
-	struct buffer_head *bh
-		= container_of(word, struct buffer_head, b_state);
-
-	smp_mb();
-	bd = bh->b_bdev;
-	if (bd)
-		blk_run_address_space(bd->bd_inode->i_mapping);
 	io_schedule();
 	return 0;
 }
 
 void __lock_buffer(struct buffer_head *bh)
 {
-	wait_on_bit_lock(&bh->b_state, BH_Lock, sync_buffer,
+	wait_on_bit_lock(&bh->b_state, BH_Lock, sleep_on_buffer,
 							TASK_UNINTERRUPTIBLE);
 }
 EXPORT_SYMBOL(__lock_buffer);
@@ -90,7 +82,7 @@ EXPORT_SYMBOL(unlock_buffer);
  */
 void __wait_on_buffer(struct buffer_head * bh)
 {
-	wait_on_bit(&bh->b_state, BH_Lock, sync_buffer, TASK_UNINTERRUPTIBLE);
+	wait_on_bit(&bh->b_state, BH_Lock, sleep_on_buffer, TASK_UNINTERRUPTIBLE);
 }
 EXPORT_SYMBOL(__wait_on_buffer);
 
@@ -749,7 +741,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list)
 {
 	struct buffer_head *bh;
 	struct list_head tmp;
-	struct address_space *mapping, *prev_mapping = NULL;
+	struct address_space *mapping;
 	int err = 0, err2;
 
 	INIT_LIST_HEAD(&tmp);
@@ -783,10 +775,6 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list)
 				 * wait_on_buffer() will do that for us
 				 * through sync_buffer().
 				 */
-				if (prev_mapping && prev_mapping != mapping)
-					blk_run_address_space(prev_mapping);
-				prev_mapping = mapping;
-
 				brelse(bh);
 				spin_lock(lock);
 			}
@@ -3138,17 +3126,6 @@ out:
 }
 EXPORT_SYMBOL(try_to_free_buffers);
 
-void block_sync_page(struct page *page)
-{
-	struct address_space *mapping;
-
-	smp_mb();
-	mapping = page_mapping(page);
-	if (mapping)
-		blk_run_backing_dev(mapping->backing_dev_info, page);
-}
-EXPORT_SYMBOL(block_sync_page);
-
 /*
  * There are no bdflush tunables left.  But distributions are
  * still running obsolete flush daemons, so we terminate them here.
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index e964b1cd5dd..c27d236738f 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1569,34 +1569,6 @@ int cifs_fsync(struct file *file, int datasync)
 	return rc;
 }
 
-/* static void cifs_sync_page(struct page *page)
-{
-	struct address_space *mapping;
-	struct inode *inode;
-	unsigned long index = page->index;
-	unsigned int rpages = 0;
-	int rc = 0;
-
-	cFYI(1, "sync page %p", page);
-	mapping = page->mapping;
-	if (!mapping)
-		return 0;
-	inode = mapping->host;
-	if (!inode)
-		return; */
-
-/*	fill in rpages then
-	result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */
-
-/*	cFYI(1, "rpages is %d for sync page of Index %ld", rpages, index);
-
-#if 0
-	if (rc < 0)
-		return rc;
-	return 0;
-#endif
-} */
-
 /*
  * As file closes, flush all cached write data for this inode checking
  * for write behind errors.
@@ -2510,7 +2482,6 @@ const struct address_space_operations cifs_addr_ops = {
 	.set_page_dirty = __set_page_dirty_nobuffers,
 	.releasepage = cifs_release_page,
 	.invalidatepage = cifs_invalidate_page,
-	/* .sync_page = cifs_sync_page, */
 	/* .direct_IO = */
 };
 
@@ -2528,6 +2499,5 @@ const struct address_space_operations cifs_addr_ops_smallbuf = {
 	.set_page_dirty = __set_page_dirty_nobuffers,
 	.releasepage = cifs_release_page,
 	.invalidatepage = cifs_invalidate_page,
-	/* .sync_page = cifs_sync_page, */
 	/* .direct_IO = */
 };
diff --git a/fs/direct-io.c b/fs/direct-io.c
index b044705eedd..df709b3b860 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -1110,11 +1110,8 @@ direct_io_worker(int rw, struct kiocb *iocb, struct inode *inode,
 	    ((rw & READ) || (dio->result == dio->size)))
 		ret = -EIOCBQUEUED;
 
-	if (ret != -EIOCBQUEUED) {
-		/* All IO is now issued, send it on its way */
-		blk_run_address_space(inode->i_mapping);
+	if (ret != -EIOCBQUEUED)
 		dio_await_completion(dio);
-	}
 
 	/*
 	 * Sync will always be dropping the final ref and completing the
diff --git a/fs/efs/inode.c b/fs/efs/inode.c
index a8e7797b947..9c13412e6c9 100644
--- a/fs/efs/inode.c
+++ b/fs/efs/inode.c
@@ -23,7 +23,6 @@ static sector_t _efs_bmap(struct address_space *mapping, sector_t block)
 }
 static const struct address_space_operations efs_aops = {
 	.readpage = efs_readpage,
-	.sync_page = block_sync_page,
 	.bmap = _efs_bmap
 };
 
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
index a7555238c41..82b94c8f5d2 100644
--- a/fs/exofs/inode.c
+++ b/fs/exofs/inode.c
@@ -795,7 +795,6 @@ const struct address_space_operations exofs_aops = {
 	.direct_IO	= NULL, /* TODO: Should be trivial to do */
 
 	/* With these NULL has special meaning or default is not exported */
-	.sync_page	= NULL,
 	.get_xip_mem	= NULL,
 	.migratepage	= NULL,
 	.launder_page	= NULL,
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 40ad210a504..c47f706878b 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -860,7 +860,6 @@ const struct address_space_operations ext2_aops = {
 	.readpage		= ext2_readpage,
 	.readpages		= ext2_readpages,
 	.writepage		= ext2_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext2_write_begin,
 	.write_end		= ext2_write_end,
 	.bmap			= ext2_bmap,
@@ -880,7 +879,6 @@ const struct address_space_operations ext2_nobh_aops = {
 	.readpage		= ext2_readpage,
 	.readpages		= ext2_readpages,
 	.writepage		= ext2_nobh_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext2_nobh_write_begin,
 	.write_end		= nobh_write_end,
 	.bmap			= ext2_bmap,
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index ae94f6d949f..fe2541d250e 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1894,7 +1894,6 @@ static const struct address_space_operations ext3_ordered_aops = {
 	.readpage		= ext3_readpage,
 	.readpages		= ext3_readpages,
 	.writepage		= ext3_ordered_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext3_write_begin,
 	.write_end		= ext3_ordered_write_end,
 	.bmap			= ext3_bmap,
@@ -1910,7 +1909,6 @@ static const struct address_space_operations ext3_writeback_aops = {
 	.readpage		= ext3_readpage,
 	.readpages		= ext3_readpages,
 	.writepage		= ext3_writeback_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext3_write_begin,
 	.write_end		= ext3_writeback_write_end,
 	.bmap			= ext3_bmap,
@@ -1926,7 +1924,6 @@ static const struct address_space_operations ext3_journalled_aops = {
 	.readpage		= ext3_readpage,
 	.readpages		= ext3_readpages,
 	.writepage		= ext3_journalled_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext3_write_begin,
 	.write_end		= ext3_journalled_write_end,
 	.set_page_dirty		= ext3_journalled_set_page_dirty,
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 9f7f9e49914..9297ad46c46 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3903,7 +3903,6 @@ static const struct address_space_operations ext4_ordered_aops = {
 	.readpage		= ext4_readpage,
 	.readpages		= ext4_readpages,
 	.writepage		= ext4_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext4_write_begin,
 	.write_end		= ext4_ordered_write_end,
 	.bmap			= ext4_bmap,
@@ -3919,7 +3918,6 @@ static const struct address_space_operations ext4_writeback_aops = {
 	.readpage		= ext4_readpage,
 	.readpages		= ext4_readpages,
 	.writepage		= ext4_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext4_write_begin,
 	.write_end		= ext4_writeback_write_end,
 	.bmap			= ext4_bmap,
@@ -3935,7 +3933,6 @@ static const struct address_space_operations ext4_journalled_aops = {
 	.readpage		= ext4_readpage,
 	.readpages		= ext4_readpages,
 	.writepage		= ext4_writepage,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext4_write_begin,
 	.write_end		= ext4_journalled_write_end,
 	.set_page_dirty		= ext4_journalled_set_page_dirty,
@@ -3951,7 +3948,6 @@ static const struct address_space_operations ext4_da_aops = {
 	.readpages		= ext4_readpages,
 	.writepage		= ext4_writepage,
 	.writepages		= ext4_da_writepages,
-	.sync_page		= block_sync_page,
 	.write_begin		= ext4_da_write_begin,
 	.write_end		= ext4_da_write_end,
 	.bmap			= ext4_bmap,
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 86753fe10bd..f4ff09fb79b 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -236,7 +236,6 @@ static const struct address_space_operations fat_aops = {
 	.readpages	= fat_readpages,
 	.writepage	= fat_writepage,
 	.writepages	= fat_writepages,
-	.sync_page	= block_sync_page,
 	.write_begin	= fat_write_begin,
 	.write_end	= fat_write_end,
 	.direct_IO	= fat_direct_IO,
diff --git a/fs/freevxfs/vxfs_subr.c b/fs/freevxfs/vxfs_subr.c
index 1429f3ae1e8..5d318c44f85 100644
--- a/fs/freevxfs/vxfs_subr.c
+++ b/fs/freevxfs/vxfs_subr.c
@@ -44,7 +44,6 @@ static sector_t		vxfs_bmap(struct address_space *, sector_t);
 const struct address_space_operations vxfs_aops = {
 	.readpage =		vxfs_readpage,
 	.bmap =			vxfs_bmap,
-	.sync_page =		block_sync_page,
 };
 
 inline void
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 9e3f68cc1bd..09e8d51eeb6 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -868,7 +868,6 @@ static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
 
 	fc->bdi.name = "fuse";
 	fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
-	fc->bdi.unplug_io_fn = default_unplug_io_fn;
 	/* fuse does it's own writeback accounting */
 	fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB;
 
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 4f36f8832b9..2f87ad27efd 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -1116,7 +1116,6 @@ static const struct address_space_operations gfs2_writeback_aops = {
 	.writepages = gfs2_writeback_writepages,
 	.readpage = gfs2_readpage,
 	.readpages = gfs2_readpages,
-	.sync_page = block_sync_page,
 	.write_begin = gfs2_write_begin,
 	.write_end = gfs2_write_end,
 	.bmap = gfs2_bmap,
@@ -1132,7 +1131,6 @@ static const struct address_space_operations gfs2_ordered_aops = {
 	.writepage = gfs2_ordered_writepage,
 	.readpage = gfs2_readpage,
 	.readpages = gfs2_readpages,
-	.sync_page = block_sync_page,
 	.write_begin = gfs2_write_begin,
 	.write_end = gfs2_write_end,
 	.set_page_dirty = gfs2_set_page_dirty,
@@ -1150,7 +1148,6 @@ static const struct address_space_operations gfs2_jdata_aops = {
 	.writepages = gfs2_jdata_writepages,
 	.readpage = gfs2_readpage,
 	.readpages = gfs2_readpages,
-	.sync_page = block_sync_page,
 	.write_begin = gfs2_write_begin,
 	.write_end = gfs2_write_end,
 	.set_page_dirty = gfs2_set_page_dirty,
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 939739c7b3f..a566331db4e 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -94,7 +94,6 @@ static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wb
 const struct address_space_operations gfs2_meta_aops = {
 	.writepage = gfs2_aspace_writepage,
 	.releasepage = gfs2_releasepage,
-	.sync_page = block_sync_page,
 };
 
 /**
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index dffb4e99664..fff16c968e6 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -150,7 +150,6 @@ static int hfs_writepages(struct address_space *mapping,
 const struct address_space_operations hfs_btree_aops = {
 	.readpage	= hfs_readpage,
 	.writepage	= hfs_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= hfs_write_begin,
 	.write_end	= generic_write_end,
 	.bmap		= hfs_bmap,
@@ -160,7 +159,6 @@ const struct address_space_operations hfs_btree_aops = {
 const struct address_space_operations hfs_aops = {
 	.readpage	= hfs_readpage,
 	.writepage	= hfs_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= hfs_write_begin,
 	.write_end	= generic_write_end,
 	.bmap		= hfs_bmap,
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index a8df651747f..b248a6cfcad 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -146,7 +146,6 @@ static int hfsplus_writepages(struct address_space *mapping,
 const struct address_space_operations hfsplus_btree_aops = {
 	.readpage	= hfsplus_readpage,
 	.writepage	= hfsplus_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= hfsplus_write_begin,
 	.write_end	= generic_write_end,
 	.bmap		= hfsplus_bmap,
@@ -156,7 +155,6 @@ const struct address_space_operations hfsplus_btree_aops = {
 const struct address_space_operations hfsplus_aops = {
 	.readpage	= hfsplus_readpage,
 	.writepage	= hfsplus_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= hfsplus_write_begin,
 	.write_end	= generic_write_end,
 	.bmap		= hfsplus_bmap,
diff --git a/fs/hpfs/file.c b/fs/hpfs/file.c
index c0340887c7e..9e84257b3ad 100644
--- a/fs/hpfs/file.c
+++ b/fs/hpfs/file.c
@@ -120,7 +120,6 @@ static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
 const struct address_space_operations hpfs_aops = {
 	.readpage = hpfs_readpage,
 	.writepage = hpfs_writepage,
-	.sync_page = block_sync_page,
 	.write_begin = hpfs_write_begin,
 	.write_end = generic_write_end,
 	.bmap = _hpfs_bmap
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index a0f3833c0db..3db5ba4568f 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -1158,7 +1158,6 @@ static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
 
 static const struct address_space_operations isofs_aops = {
 	.readpage = isofs_readpage,
-	.sync_page = block_sync_page,
 	.bmap = _isofs_bmap
 };
 
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index 9978803ceed..eddbb373209 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
@@ -352,7 +352,6 @@ const struct address_space_operations jfs_aops = {
 	.readpages	= jfs_readpages,
 	.writepage	= jfs_writepage,
 	.writepages	= jfs_writepages,
-	.sync_page	= block_sync_page,
 	.write_begin	= jfs_write_begin,
 	.write_end	= nobh_write_end,
 	.bmap		= jfs_bmap,
diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c
index 48b44bd8267..6740d34cd82 100644
--- a/fs/jfs/jfs_metapage.c
+++ b/fs/jfs/jfs_metapage.c
@@ -583,7 +583,6 @@ static void metapage_invalidatepage(struct page *page, unsigned long offset)
 const struct address_space_operations jfs_metapage_aops = {
 	.readpage	= metapage_readpage,
 	.writepage	= metapage_writepage,
-	.sync_page	= block_sync_page,
 	.releasepage	= metapage_releasepage,
 	.invalidatepage	= metapage_invalidatepage,
 	.set_page_dirty	= __set_page_dirty_nobuffers,
diff --git a/fs/logfs/dev_bdev.c b/fs/logfs/dev_bdev.c
index 723bc5bca09..1adc8d455f0 100644
--- a/fs/logfs/dev_bdev.c
+++ b/fs/logfs/dev_bdev.c
@@ -39,7 +39,6 @@ static int sync_request(struct page *page, struct block_device *bdev, int rw)
 	bio.bi_end_io = request_complete;
 
 	submit_bio(rw, &bio);
-	generic_unplug_device(bdev_get_queue(bdev));
 	wait_for_completion(&complete);
 	return test_bit(BIO_UPTODATE, &bio.bi_flags) ? 0 : -EIO;
 }
@@ -168,7 +167,6 @@ static void bdev_writeseg(struct super_block *sb, u64 ofs, size_t len)
 	}
 	len = PAGE_ALIGN(len);
 	__bdev_writeseg(sb, ofs, ofs >> PAGE_SHIFT, len >> PAGE_SHIFT);
-	generic_unplug_device(bdev_get_queue(logfs_super(sb)->s_bdev));
 }
 
 
diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index ae0b83f476a..adcdc0a4e18 100644
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -399,7 +399,6 @@ static sector_t minix_bmap(struct address_space *mapping, sector_t block)
 static const struct address_space_operations minix_aops = {
 	.readpage = minix_readpage,
 	.writepage = minix_writepage,
-	.sync_page = block_sync_page,
 	.write_begin = minix_write_begin,
 	.write_end = generic_write_end,
 	.bmap = minix_bmap
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 388e9e8f528..f4f1c08807e 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -40,14 +40,10 @@ void nilfs_btnode_cache_init_once(struct address_space *btnc)
 	nilfs_mapping_init_once(btnc);
 }
 
-static const struct address_space_operations def_btnode_aops = {
-	.sync_page		= block_sync_page,
-};
-
 void nilfs_btnode_cache_init(struct address_space *btnc,
 			     struct backing_dev_info *bdi)
 {
-	nilfs_mapping_init(btnc, bdi, &def_btnode_aops);
+	nilfs_mapping_init(btnc, bdi);
 }
 
 void nilfs_btnode_cache_clear(struct address_space *btnc)
diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c
index caf9a6a3fb5..1c2a3e23f8b 100644
--- a/fs/nilfs2/gcinode.c
+++ b/fs/nilfs2/gcinode.c
@@ -49,7 +49,6 @@
 #include "ifile.h"
 
 static const struct address_space_operations def_gcinode_aops = {
-	.sync_page		= block_sync_page,
 };
 
 /*
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 2fd440d8d6b..c89d5d1ea7c 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -262,7 +262,6 @@ nilfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
 const struct address_space_operations nilfs_aops = {
 	.writepage		= nilfs_writepage,
 	.readpage		= nilfs_readpage,
-	.sync_page		= block_sync_page,
 	.writepages		= nilfs_writepages,
 	.set_page_dirty		= nilfs_set_page_dirty,
 	.readpages		= nilfs_readpages,
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 6a0e2a189f6..3fdb61d79c9 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -399,7 +399,6 @@ nilfs_mdt_write_page(struct page *page, struct writeback_control *wbc)
 
 static const struct address_space_operations def_mdt_aops = {
 	.writepage		= nilfs_mdt_write_page,
-	.sync_page		= block_sync_page,
 };
 
 static const struct inode_operations def_mdt_iops;
@@ -438,10 +437,6 @@ void nilfs_mdt_set_entry_size(struct inode *inode, unsigned entry_size,
 	mi->mi_first_entry_offset = DIV_ROUND_UP(header_size, entry_size);
 }
 
-static const struct address_space_operations shadow_map_aops = {
-	.sync_page		= block_sync_page,
-};
-
 /**
  * nilfs_mdt_setup_shadow_map - setup shadow map and bind it to metadata file
  * @inode: inode of the metadata file
@@ -455,9 +450,9 @@ int nilfs_mdt_setup_shadow_map(struct inode *inode,
 
 	INIT_LIST_HEAD(&shadow->frozen_buffers);
 	nilfs_mapping_init_once(&shadow->frozen_data);
-	nilfs_mapping_init(&shadow->frozen_data, bdi, &shadow_map_aops);
+	nilfs_mapping_init(&shadow->frozen_data, bdi);
 	nilfs_mapping_init_once(&shadow->frozen_btnodes);
-	nilfs_mapping_init(&shadow->frozen_btnodes, bdi, &shadow_map_aops);
+	nilfs_mapping_init(&shadow->frozen_btnodes, bdi);
 	mi->mi_shadow = shadow;
 	return 0;
 }
diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index 0c432416cfe..3da37cc5de3 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -506,15 +506,14 @@ void nilfs_mapping_init_once(struct address_space *mapping)
 }
 
 void nilfs_mapping_init(struct address_space *mapping,
-			struct backing_dev_info *bdi,
-			const struct address_space_operations *aops)
+			struct backing_dev_info *bdi)
 {
 	mapping->host = NULL;
 	mapping->flags = 0;
 	mapping_set_gfp_mask(mapping, GFP_NOFS);
 	mapping->assoc_mapping = NULL;
 	mapping->backing_dev_info = bdi;
-	mapping->a_ops = aops;
+	mapping->a_ops = NULL;
 }
 
 /*
diff --git a/fs/nilfs2/page.h b/fs/nilfs2/page.h
index 622df27cd89..ba4d6fd40b0 100644
--- a/fs/nilfs2/page.h
+++ b/fs/nilfs2/page.h
@@ -63,8 +63,7 @@ void nilfs_copy_back_pages(struct address_space *, struct address_space *);
 void nilfs_clear_dirty_pages(struct address_space *);
 void nilfs_mapping_init_once(struct address_space *mapping);
 void nilfs_mapping_init(struct address_space *mapping,
-			struct backing_dev_info *bdi,
-			const struct address_space_operations *aops);
+			struct backing_dev_info *bdi);
 unsigned nilfs_page_count_clean_buffers(struct page *, unsigned, unsigned);
 unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
 					    sector_t start_blk,
diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c
index c3c2c7ac902..0b1e885b8cf 100644
--- a/fs/ntfs/aops.c
+++ b/fs/ntfs/aops.c
@@ -1543,8 +1543,6 @@ err_out:
  */
 const struct address_space_operations ntfs_aops = {
 	.readpage	= ntfs_readpage,	/* Fill page with data. */
-	.sync_page	= block_sync_page,	/* Currently, just unplugs the
-						   disk request queue. */
 #ifdef NTFS_RW
 	.writepage	= ntfs_writepage,	/* Write dirty page to disk. */
 #endif /* NTFS_RW */
@@ -1560,8 +1558,6 @@ const struct address_space_operations ntfs_aops = {
  */
 const struct address_space_operations ntfs_mst_aops = {
 	.readpage	= ntfs_readpage,	/* Fill page with data. */
-	.sync_page	= block_sync_page,	/* Currently, just unplugs the
-						   disk request queue. */
 #ifdef NTFS_RW
 	.writepage	= ntfs_writepage,	/* Write dirty page to disk. */
 	.set_page_dirty	= __set_page_dirty_nobuffers,	/* Set the page dirty
diff --git a/fs/ntfs/compress.c b/fs/ntfs/compress.c
index 6551c7cbad9..ef9ed854255 100644
--- a/fs/ntfs/compress.c
+++ b/fs/ntfs/compress.c
@@ -698,8 +698,7 @@ lock_retry_remap:
 					"uptodate! Unplugging the disk queue "
 					"and rescheduling.");
 			get_bh(tbh);
-			blk_run_address_space(mapping);
-			schedule();
+			io_schedule();
 			put_bh(tbh);
 			if (unlikely(!buffer_uptodate(tbh)))
 				goto read_err;
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 1fbb0e20131..daea0359e97 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -2043,7 +2043,6 @@ const struct address_space_operations ocfs2_aops = {
 	.write_begin		= ocfs2_write_begin,
 	.write_end		= ocfs2_write_end,
 	.bmap			= ocfs2_bmap,
-	.sync_page		= block_sync_page,
 	.direct_IO		= ocfs2_direct_IO,
 	.invalidatepage		= ocfs2_invalidatepage,
 	.releasepage		= ocfs2_releasepage,
diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index b108e863d8f..1adab287bd2 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -367,11 +367,7 @@ static inline void o2hb_bio_wait_dec(struct o2hb_bio_wait_ctxt *wc,
 static void o2hb_wait_on_io(struct o2hb_region *reg,
 			    struct o2hb_bio_wait_ctxt *wc)
 {
-	struct address_space *mapping = reg->hr_bdev->bd_inode->i_mapping;
-
-	blk_run_address_space(mapping);
 	o2hb_bio_wait_dec(wc, 1);
-
 	wait_for_completion(&wc->wc_io_complete);
 }
 
diff --git a/fs/omfs/file.c b/fs/omfs/file.c
index 8a6d34fa668..d738a7e493d 100644
--- a/fs/omfs/file.c
+++ b/fs/omfs/file.c
@@ -372,7 +372,6 @@ const struct address_space_operations omfs_aops = {
 	.readpages = omfs_readpages,
 	.writepage = omfs_writepage,
 	.writepages = omfs_writepages,
-	.sync_page = block_sync_page,
 	.write_begin = omfs_write_begin,
 	.write_end = generic_write_end,
 	.bmap = omfs_bmap,
diff --git a/fs/qnx4/inode.c b/fs/qnx4/inode.c
index e63b4171d58..2b0646613f5 100644
--- a/fs/qnx4/inode.c
+++ b/fs/qnx4/inode.c
@@ -335,7 +335,6 @@ static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
 static const struct address_space_operations qnx4_aops = {
 	.readpage	= qnx4_readpage,
 	.writepage	= qnx4_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin	= qnx4_write_begin,
 	.write_end	= generic_write_end,
 	.bmap		= qnx4_bmap
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index 0bae036831e..03674675f88 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -3212,7 +3212,6 @@ const struct address_space_operations reiserfs_address_space_operations = {
 	.readpages = reiserfs_readpages,
 	.releasepage = reiserfs_releasepage,
 	.invalidatepage = reiserfs_invalidatepage,
-	.sync_page = block_sync_page,
 	.write_begin = reiserfs_write_begin,
 	.write_end = reiserfs_write_end,
 	.bmap = reiserfs_aop_bmap,
diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c
index 9ca66276315..fa8d43c92bb 100644
--- a/fs/sysv/itree.c
+++ b/fs/sysv/itree.c
@@ -488,7 +488,6 @@ static sector_t sysv_bmap(struct address_space *mapping, sector_t block)
 const struct address_space_operations sysv_aops = {
 	.readpage = sysv_readpage,
 	.writepage = sysv_writepage,
-	.sync_page = block_sync_page,
 	.write_begin = sysv_write_begin,
 	.write_end = generic_write_end,
 	.bmap = sysv_bmap
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 6e11c2975dc..81368d4d4a2 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1979,7 +1979,6 @@ static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
 	 */
 	c->bdi.name = "ubifs",
 	c->bdi.capabilities = BDI_CAP_MAP_COPY;
-	c->bdi.unplug_io_fn = default_unplug_io_fn;
 	err  = bdi_init(&c->bdi);
 	if (err)
 		goto out_close;
diff --git a/fs/udf/file.c b/fs/udf/file.c
index 89c78486cbb..94e4553491c 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -98,7 +98,6 @@ static int udf_adinicb_write_end(struct file *file,
 const struct address_space_operations udf_adinicb_aops = {
 	.readpage	= udf_adinicb_readpage,
 	.writepage	= udf_adinicb_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin = simple_write_begin,
 	.write_end = udf_adinicb_write_end,
 };
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index c6a2e782b97..fa96fc0fe12 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -133,7 +133,6 @@ static sector_t udf_bmap(struct address_space *mapping, sector_t block)
 const struct address_space_operations udf_aops = {
 	.readpage	= udf_readpage,
 	.writepage	= udf_writepage,
-	.sync_page	= block_sync_page,
 	.write_begin		= udf_write_begin,
 	.write_end		= generic_write_end,
 	.bmap		= udf_bmap,
diff --git a/fs/ufs/inode.c b/fs/ufs/inode.c
index 2b251f2093a..83b28444eb1 100644
--- a/fs/ufs/inode.c
+++ b/fs/ufs/inode.c
@@ -588,7 +588,6 @@ static sector_t ufs_bmap(struct address_space *mapping, sector_t block)
 const struct address_space_operations ufs_aops = {
 	.readpage = ufs_readpage,
 	.writepage = ufs_writepage,
-	.sync_page = block_sync_page,
 	.write_begin = ufs_write_begin,
 	.write_end = generic_write_end,
 	.bmap = ufs_bmap
diff --git a/fs/ufs/truncate.c b/fs/ufs/truncate.c
index a58f9155fc9..ff0e79276f2 100644
--- a/fs/ufs/truncate.c
+++ b/fs/ufs/truncate.c
@@ -481,7 +481,7 @@ int ufs_truncate(struct inode *inode, loff_t old_i_size)
 			break;
 		if (IS_SYNC(inode) && (inode->i_state & I_DIRTY))
 			ufs_sync_inode (inode);
-		blk_run_address_space(inode->i_mapping);
+		blk_flush_plug(current);
 		yield();
 	}
 
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index ec7bbb5645b..83c1c20d145 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -1495,7 +1495,6 @@ const struct address_space_operations xfs_address_space_operations = {
 	.readpages		= xfs_vm_readpages,
 	.writepage		= xfs_vm_writepage,
 	.writepages		= xfs_vm_writepages,
-	.sync_page		= block_sync_page,
 	.releasepage		= xfs_vm_releasepage,
 	.invalidatepage		= xfs_vm_invalidatepage,
 	.write_begin		= xfs_vm_write_begin,
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index ac1c7e8378d..4f8f53c4d42 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -991,7 +991,7 @@ xfs_buf_lock(
 	if (atomic_read(&bp->b_pin_count) && (bp->b_flags & XBF_STALE))
 		xfs_log_force(bp->b_target->bt_mount, 0);
 	if (atomic_read(&bp->b_io_remaining))
-		blk_run_address_space(bp->b_target->bt_mapping);
+		blk_flush_plug(current);
 	down(&bp->b_sema);
 	XB_SET_OWNER(bp);
 
@@ -1035,9 +1035,7 @@ xfs_buf_wait_unpin(
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		if (atomic_read(&bp->b_pin_count) == 0)
 			break;
-		if (atomic_read(&bp->b_io_remaining))
-			blk_run_address_space(bp->b_target->bt_mapping);
-		schedule();
+		io_schedule();
 	}
 	remove_wait_queue(&bp->b_waiters, &wait);
 	set_current_state(TASK_RUNNING);
@@ -1443,7 +1441,7 @@ xfs_buf_iowait(
 	trace_xfs_buf_iowait(bp, _RET_IP_);
 
 	if (atomic_read(&bp->b_io_remaining))
-		blk_run_address_space(bp->b_target->bt_mapping);
+		blk_flush_plug(current);
 	wait_for_completion(&bp->b_iowait);
 
 	trace_xfs_buf_iowait_done(bp, _RET_IP_);
@@ -1667,7 +1665,6 @@ xfs_mapping_buftarg(
 	struct inode		*inode;
 	struct address_space	*mapping;
 	static const struct address_space_operations mapping_aops = {
-		.sync_page = block_sync_page,
 		.migratepage = fail_migrate_page,
 	};
 
@@ -1948,7 +1945,7 @@ xfsbufd(
 			count++;
 		}
 		if (count)
-			blk_run_address_space(target->bt_mapping);
+			blk_flush_plug(current);
 
 	} while (!kthread_should_stop());
 
@@ -1996,7 +1993,7 @@ xfs_flush_buftarg(
 
 	if (wait) {
 		/* Expedite and wait for IO to complete. */
-		blk_run_address_space(target->bt_mapping);
+		blk_flush_plug(current);
 		while (!list_empty(&wait_list)) {
 			bp = list_first_entry(&wait_list, struct xfs_buf, b_list);
 
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 4ce34fa937d..96f4094b706 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -66,8 +66,6 @@ struct backing_dev_info {
 	unsigned int capabilities; /* Device capabilities */
 	congested_fn *congested_fn; /* Function pointer if device is md/dm */
 	void *congested_data;	/* Pointer to aux data for congested func */
-	void (*unplug_io_fn)(struct backing_dev_info *, struct page *);
-	void *unplug_io_data;
 
 	char *name;
 
@@ -251,7 +249,6 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio);
 
 extern struct backing_dev_info default_backing_dev_info;
 extern struct backing_dev_info noop_backing_dev_info;
-void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page);
 
 int writeback_in_progress(struct backing_dev_info *bdi);
 
@@ -336,17 +333,4 @@ static inline int bdi_sched_wait(void *word)
 	return 0;
 }
 
-static inline void blk_run_backing_dev(struct backing_dev_info *bdi,
-				       struct page *page)
-{
-	if (bdi && bdi->unplug_io_fn)
-		bdi->unplug_io_fn(bdi, page);
-}
-
-static inline void blk_run_address_space(struct address_space *mapping)
-{
-	if (mapping)
-		blk_run_backing_dev(mapping->backing_dev_info, NULL);
-}
-
 #endif		/* _LINUX_BACKING_DEV_H */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 5873037eeb9..64ab2a1bb16 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -196,7 +196,6 @@ typedef void (request_fn_proc) (struct request_queue *q);
 typedef int (make_request_fn) (struct request_queue *q, struct bio *bio);
 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
-typedef void (unplug_fn) (struct request_queue *);
 
 struct bio_vec;
 struct bvec_merge_data {
@@ -279,7 +278,6 @@ struct request_queue
 	make_request_fn		*make_request_fn;
 	prep_rq_fn		*prep_rq_fn;
 	unprep_rq_fn		*unprep_rq_fn;
-	unplug_fn		*unplug_fn;
 	merge_bvec_fn		*merge_bvec_fn;
 	softirq_done_fn		*softirq_done_fn;
 	rq_timed_out_fn		*rq_timed_out_fn;
@@ -292,14 +290,6 @@ struct request_queue
 	sector_t		end_sector;
 	struct request		*boundary_rq;
 
-	/*
-	 * Auto-unplugging state
-	 */
-	struct timer_list	unplug_timer;
-	int			unplug_thresh;	/* After this many requests */
-	unsigned long		unplug_delay;	/* After this many jiffies */
-	struct work_struct	unplug_work;
-
 	/*
 	 * Delayed queue handling
 	 */
@@ -399,14 +389,13 @@ struct request_queue
 #define QUEUE_FLAG_ASYNCFULL	4	/* write queue has been filled */
 #define QUEUE_FLAG_DEAD		5	/* queue being torn down */
 #define QUEUE_FLAG_REENTER	6	/* Re-entrancy avoidance */
-#define QUEUE_FLAG_PLUGGED	7	/* queue is plugged */
-#define QUEUE_FLAG_ELVSWITCH	8	/* don't use elevator, just do FIFO */
-#define QUEUE_FLAG_BIDI		9	/* queue supports bidi requests */
-#define QUEUE_FLAG_NOMERGES    10	/* disable merge attempts */
-#define QUEUE_FLAG_SAME_COMP   11	/* force complete on same CPU */
-#define QUEUE_FLAG_FAIL_IO     12	/* fake timeout */
-#define QUEUE_FLAG_STACKABLE   13	/* supports request stacking */
-#define QUEUE_FLAG_NONROT      14	/* non-rotational device (SSD) */
+#define QUEUE_FLAG_ELVSWITCH	7	/* don't use elevator, just do FIFO */
+#define QUEUE_FLAG_BIDI		8	/* queue supports bidi requests */
+#define QUEUE_FLAG_NOMERGES     9	/* disable merge attempts */
+#define QUEUE_FLAG_SAME_COMP   10	/* force complete on same CPU */
+#define QUEUE_FLAG_FAIL_IO     11	/* fake timeout */
+#define QUEUE_FLAG_STACKABLE   12	/* supports request stacking */
+#define QUEUE_FLAG_NONROT      13	/* non-rotational device (SSD) */
 #define QUEUE_FLAG_VIRT        QUEUE_FLAG_NONROT /* paravirt device */
 #define QUEUE_FLAG_IO_STAT     15	/* do IO stats */
 #define QUEUE_FLAG_DISCARD     16	/* supports DISCARD */
@@ -484,7 +473,6 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 	__clear_bit(flag, &q->queue_flags);
 }
 
-#define blk_queue_plugged(q)	test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags)
 #define blk_queue_tagged(q)	test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
 #define blk_queue_stopped(q)	test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
 #define blk_queue_nomerges(q)	test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
@@ -679,9 +667,6 @@ extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
 extern void blk_rq_unprep_clone(struct request *rq);
 extern int blk_insert_cloned_request(struct request_queue *q,
 				     struct request *rq);
-extern void blk_plug_device(struct request_queue *);
-extern void blk_plug_device_unlocked(struct request_queue *);
-extern int blk_remove_plug(struct request_queue *);
 extern void blk_delay_queue(struct request_queue *, unsigned long);
 extern void blk_recount_segments(struct request_queue *, struct bio *);
 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
@@ -726,7 +711,6 @@ extern int blk_execute_rq(struct request_queue *, struct gendisk *,
 			  struct request *, int);
 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
 				  struct request *, int, rq_end_io_fn *);
-extern void blk_unplug(struct request_queue *q);
 
 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
 {
@@ -863,7 +847,6 @@ extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bd
 
 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
 extern void blk_dump_rq_flags(struct request *, char *);
-extern void generic_unplug_device(struct request_queue *);
 extern long nr_blockdev_pages(void);
 
 int blk_get_queue(struct request_queue *);
diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index 68d1fe7b877..f5df23561b9 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -219,7 +219,6 @@ int generic_cont_expand_simple(struct inode *inode, loff_t size);
 int block_commit_write(struct page *page, unsigned from, unsigned to);
 int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
 				get_block_t get_block);
-void block_sync_page(struct page *);
 sector_t generic_block_bmap(struct address_space *, sector_t, get_block_t *);
 int block_truncate_page(struct address_space *, loff_t, get_block_t *);
 int nobh_write_begin(struct address_space *, loff_t, unsigned, unsigned,
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 272496d1fae..e2768834f39 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -285,11 +285,6 @@ void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callback
  */
 int dm_table_complete(struct dm_table *t);
 
-/*
- * Unplug all devices in a table.
- */
-void dm_table_unplug_all(struct dm_table *t);
-
 /*
  * Table reference counting.
  */
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 8857cf9adbb..ec6f72b8447 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -20,7 +20,6 @@ typedef void (elevator_bio_merged_fn) (struct request_queue *,
 typedef int (elevator_dispatch_fn) (struct request_queue *, int);
 
 typedef void (elevator_add_req_fn) (struct request_queue *, struct request *);
-typedef int (elevator_queue_empty_fn) (struct request_queue *);
 typedef struct request *(elevator_request_list_fn) (struct request_queue *, struct request *);
 typedef void (elevator_completed_req_fn) (struct request_queue *, struct request *);
 typedef int (elevator_may_queue_fn) (struct request_queue *, int);
@@ -46,7 +45,6 @@ struct elevator_ops
 	elevator_activate_req_fn *elevator_activate_req_fn;
 	elevator_deactivate_req_fn *elevator_deactivate_req_fn;
 
-	elevator_queue_empty_fn *elevator_queue_empty_fn;
 	elevator_completed_req_fn *elevator_completed_req_fn;
 
 	elevator_request_list_fn *elevator_former_req_fn;
@@ -101,8 +99,8 @@ struct elevator_queue
  */
 extern void elv_dispatch_sort(struct request_queue *, struct request *);
 extern void elv_dispatch_add_tail(struct request_queue *, struct request *);
-extern void elv_add_request(struct request_queue *, struct request *, int, int);
-extern void __elv_add_request(struct request_queue *, struct request *, int, int);
+extern void elv_add_request(struct request_queue *, struct request *, int);
+extern void __elv_add_request(struct request_queue *, struct request *, int);
 extern void elv_insert(struct request_queue *, struct request *, int);
 extern int elv_merge(struct request_queue *, struct request **, struct bio *);
 extern int elv_try_merge(struct request *, struct bio *);
@@ -112,7 +110,6 @@ extern void elv_merged_request(struct request_queue *, struct request *, int);
 extern void elv_bio_merged(struct request_queue *q, struct request *,
 				struct bio *);
 extern void elv_requeue_request(struct request_queue *, struct request *);
-extern int elv_queue_empty(struct request_queue *);
 extern struct request *elv_former_request(struct request_queue *, struct request *);
 extern struct request *elv_latter_request(struct request_queue *, struct request *);
 extern int elv_register_queue(struct request_queue *q);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index bd3215940c3..9f2cf69911b 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -583,7 +583,6 @@ typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
 struct address_space_operations {
 	int (*writepage)(struct page *page, struct writeback_control *wbc);
 	int (*readpage)(struct file *, struct page *);
-	void (*sync_page)(struct page *);
 
 	/* Write back some dirty pages from this mapping. */
 	int (*writepages)(struct address_space *, struct writeback_control *);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 9c66e994540..e112b8db2f3 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -298,7 +298,6 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
 
 extern void __lock_page(struct page *page);
 extern int __lock_page_killable(struct page *page);
-extern void __lock_page_nosync(struct page *page);
 extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
 				unsigned int flags);
 extern void unlock_page(struct page *page);
@@ -341,17 +340,6 @@ static inline int lock_page_killable(struct page *page)
 	return 0;
 }
 
-/*
- * lock_page_nosync should only be used if we can't pin the page's inode.
- * Doesn't play quite so well with block device plugging.
- */
-static inline void lock_page_nosync(struct page *page)
-{
-	might_sleep();
-	if (!trylock_page(page))
-		__lock_page_nosync(page);
-}
-	
 /*
  * lock_page_or_retry - Lock the page, unless this would block and the
  * caller indicated that it can handle a retry.
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 4d559325d91..9ee321833b2 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -299,8 +299,6 @@ extern void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
 					struct page **pagep, swp_entry_t *ent);
 #endif
 
-extern void swap_unplug_io_fn(struct backing_dev_info *, struct page *);
-
 #ifdef CONFIG_SWAP
 /* linux/mm/page_io.c */
 extern int swap_readpage(struct page *);
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 027100d3022..c91e139a652 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -14,17 +14,11 @@
 
 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
 
-void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-}
-EXPORT_SYMBOL(default_unplug_io_fn);
-
 struct backing_dev_info default_backing_dev_info = {
 	.name		= "default",
 	.ra_pages	= VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE,
 	.state		= 0,
 	.capabilities	= BDI_CAP_MAP_COPY,
-	.unplug_io_fn	= default_unplug_io_fn,
 };
 EXPORT_SYMBOL_GPL(default_backing_dev_info);
 
diff --git a/mm/filemap.c b/mm/filemap.c
index 83a45d35468..380776c2a9a 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -155,45 +155,15 @@ void remove_from_page_cache(struct page *page)
 }
 EXPORT_SYMBOL(remove_from_page_cache);
 
-static int sync_page(void *word)
+static int sleep_on_page(void *word)
 {
-	struct address_space *mapping;
-	struct page *page;
-
-	page = container_of((unsigned long *)word, struct page, flags);
-
-	/*
-	 * page_mapping() is being called without PG_locked held.
-	 * Some knowledge of the state and use of the page is used to
-	 * reduce the requirements down to a memory barrier.
-	 * The danger here is of a stale page_mapping() return value
-	 * indicating a struct address_space different from the one it's
-	 * associated with when it is associated with one.
-	 * After smp_mb(), it's either the correct page_mapping() for
-	 * the page, or an old page_mapping() and the page's own
-	 * page_mapping() has gone NULL.
-	 * The ->sync_page() address_space operation must tolerate
-	 * page_mapping() going NULL. By an amazing coincidence,
-	 * this comes about because none of the users of the page
-	 * in the ->sync_page() methods make essential use of the
-	 * page_mapping(), merely passing the page down to the backing
-	 * device's unplug functions when it's non-NULL, which in turn
-	 * ignore it for all cases but swap, where only page_private(page) is
-	 * of interest. When page_mapping() does go NULL, the entire
-	 * call stack gracefully ignores the page and returns.
-	 * -- wli
-	 */
-	smp_mb();
-	mapping = page_mapping(page);
-	if (mapping && mapping->a_ops && mapping->a_ops->sync_page)
-		mapping->a_ops->sync_page(page);
 	io_schedule();
 	return 0;
 }
 
-static int sync_page_killable(void *word)
+static int sleep_on_page_killable(void *word)
 {
-	sync_page(word);
+	sleep_on_page(word);
 	return fatal_signal_pending(current) ? -EINTR : 0;
 }
 
@@ -479,12 +449,6 @@ struct page *__page_cache_alloc(gfp_t gfp)
 EXPORT_SYMBOL(__page_cache_alloc);
 #endif
 
-static int __sleep_on_page_lock(void *word)
-{
-	io_schedule();
-	return 0;
-}
-
 /*
  * In order to wait for pages to become available there must be
  * waitqueues associated with pages. By using a hash table of
@@ -512,7 +476,7 @@ void wait_on_page_bit(struct page *page, int bit_nr)
 	DEFINE_WAIT_BIT(wait, &page->flags, bit_nr);
 
 	if (test_bit(bit_nr, &page->flags))
-		__wait_on_bit(page_waitqueue(page), &wait, sync_page,
+		__wait_on_bit(page_waitqueue(page), &wait, sleep_on_page,
 							TASK_UNINTERRUPTIBLE);
 }
 EXPORT_SYMBOL(wait_on_page_bit);
@@ -576,17 +540,12 @@ EXPORT_SYMBOL(end_page_writeback);
 /**
  * __lock_page - get a lock on the page, assuming we need to sleep to get it
  * @page: the page to lock
- *
- * Ugly. Running sync_page() in state TASK_UNINTERRUPTIBLE is scary.  If some
- * random driver's requestfn sets TASK_RUNNING, we could busywait.  However
- * chances are that on the second loop, the block layer's plug list is empty,
- * so sync_page() will then return in state TASK_UNINTERRUPTIBLE.
  */
 void __lock_page(struct page *page)
 {
 	DEFINE_WAIT_BIT(wait, &page->flags, PG_locked);
 
-	__wait_on_bit_lock(page_waitqueue(page), &wait, sync_page,
+	__wait_on_bit_lock(page_waitqueue(page), &wait, sleep_on_page,
 							TASK_UNINTERRUPTIBLE);
 }
 EXPORT_SYMBOL(__lock_page);
@@ -596,24 +555,10 @@ int __lock_page_killable(struct page *page)
 	DEFINE_WAIT_BIT(wait, &page->flags, PG_locked);
 
 	return __wait_on_bit_lock(page_waitqueue(page), &wait,
-					sync_page_killable, TASK_KILLABLE);
+					sleep_on_page_killable, TASK_KILLABLE);
 }
 EXPORT_SYMBOL_GPL(__lock_page_killable);
 
-/**
- * __lock_page_nosync - get a lock on the page, without calling sync_page()
- * @page: the page to lock
- *
- * Variant of lock_page that does not require the caller to hold a reference
- * on the page's mapping.
- */
-void __lock_page_nosync(struct page *page)
-{
-	DEFINE_WAIT_BIT(wait, &page->flags, PG_locked);
-	__wait_on_bit_lock(page_waitqueue(page), &wait, __sleep_on_page_lock,
-							TASK_UNINTERRUPTIBLE);
-}
-
 int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
 			 unsigned int flags)
 {
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 0207c2f6f8b..bfba796d374 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -945,7 +945,7 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 		collect_procs(ppage, &tokill);
 
 	if (hpage != ppage)
-		lock_page_nosync(ppage);
+		lock_page(ppage);
 
 	ret = try_to_unmap(ppage, ttu);
 	if (ret != SWAP_SUCCESS)
@@ -1038,7 +1038,7 @@ int __memory_failure(unsigned long pfn, int trapno, int flags)
 			 * Check "just unpoisoned", "filter hit", and
 			 * "race with other subpage."
 			 */
-			lock_page_nosync(hpage);
+			lock_page(hpage);
 			if (!PageHWPoison(hpage)
 			    || (hwpoison_filter(p) && TestClearPageHWPoison(p))
 			    || (p != hpage && TestSetPageHWPoison(hpage))) {
@@ -1088,7 +1088,7 @@ int __memory_failure(unsigned long pfn, int trapno, int flags)
 	 * It's very difficult to mess with pages currently under IO
 	 * and in many cases impossible, so we just avoid it here.
 	 */
-	lock_page_nosync(hpage);
+	lock_page(hpage);
 
 	/*
 	 * unpoison always clear PG_hwpoison inside page lock
@@ -1231,7 +1231,7 @@ int unpoison_memory(unsigned long pfn)
 		return 0;
 	}
 
-	lock_page_nosync(page);
+	lock_page(page);
 	/*
 	 * This test is racy because PG_hwpoison is set outside of page lock.
 	 * That's acceptable because that won't trigger kernel panic. Instead,
diff --git a/mm/nommu.c b/mm/nommu.c
index f59e1424d3d..fb6cbd6abe1 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1842,10 +1842,6 @@ int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
 }
 EXPORT_SYMBOL(remap_vmalloc_range);
 
-void swap_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-}
-
 unsigned long arch_get_unmapped_area(struct file *file, unsigned long addr,
 	unsigned long len, unsigned long pgoff, unsigned long flags)
 {
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 2cb01f6ec5d..cc0ede169e4 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1239,7 +1239,7 @@ int set_page_dirty_lock(struct page *page)
 {
 	int ret;
 
-	lock_page_nosync(page);
+	lock_page(page);
 	ret = set_page_dirty(page);
 	unlock_page(page);
 	return ret;
diff --git a/mm/readahead.c b/mm/readahead.c
index 77506a291a2..cbddc3e1724 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -554,17 +554,5 @@ page_cache_async_readahead(struct address_space *mapping,
 
 	/* do read-ahead */
 	ondemand_readahead(mapping, ra, filp, true, offset, req_size);
-
-#ifdef CONFIG_BLOCK
-	/*
-	 * Normally the current page is !uptodate and lock_page() will be
-	 * immediately called to implicitly unplug the device. However this
-	 * is not always true for RAID conifgurations, where data arrives
-	 * not strictly in their submission order. In this case we need to
-	 * explicitly kick off the IO.
-	 */
-	if (PageUptodate(page))
-		blk_run_backing_dev(mapping->backing_dev_info, NULL);
-#endif
 }
 EXPORT_SYMBOL_GPL(page_cache_async_readahead);
diff --git a/mm/shmem.c b/mm/shmem.c
index 5ee67c99060..24d23f5bedf 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -224,7 +224,6 @@ static const struct vm_operations_struct shmem_vm_ops;
 static struct backing_dev_info shmem_backing_dev_info  __read_mostly = {
 	.ra_pages	= 0,	/* No readahead */
 	.capabilities	= BDI_CAP_NO_ACCT_AND_WRITEBACK | BDI_CAP_SWAP_BACKED,
-	.unplug_io_fn	= default_unplug_io_fn,
 };
 
 static LIST_HEAD(shmem_swaplist);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 5c8cfabbc9b..46680461785 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -24,12 +24,10 @@
 
 /*
  * swapper_space is a fiction, retained to simplify the path through
- * vmscan's shrink_page_list, to make sync_page look nicer, and to allow
- * future use of radix_tree tags in the swap cache.
+ * vmscan's shrink_page_list.
  */
 static const struct address_space_operations swap_aops = {
 	.writepage	= swap_writepage,
-	.sync_page	= block_sync_page,
 	.set_page_dirty	= __set_page_dirty_nobuffers,
 	.migratepage	= migrate_page,
 };
@@ -37,7 +35,6 @@ static const struct address_space_operations swap_aops = {
 static struct backing_dev_info swap_backing_dev_info = {
 	.name		= "swap",
 	.capabilities	= BDI_CAP_NO_ACCT_AND_WRITEBACK | BDI_CAP_SWAP_BACKED,
-	.unplug_io_fn	= swap_unplug_io_fn,
 };
 
 struct address_space swapper_space = {
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 07a458d72fa..7ceea78ceb2 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -94,39 +94,6 @@ __try_to_reclaim_swap(struct swap_info_struct *si, unsigned long offset)
 	return ret;
 }
 
-/*
- * We need this because the bdev->unplug_fn can sleep and we cannot
- * hold swap_lock while calling the unplug_fn. And swap_lock
- * cannot be turned into a mutex.
- */
-static DECLARE_RWSEM(swap_unplug_sem);
-
-void swap_unplug_io_fn(struct backing_dev_info *unused_bdi, struct page *page)
-{
-	swp_entry_t entry;
-
-	down_read(&swap_unplug_sem);
-	entry.val = page_private(page);
-	if (PageSwapCache(page)) {
-		struct block_device *bdev = swap_info[swp_type(entry)]->bdev;
-		struct backing_dev_info *bdi;
-
-		/*
-		 * If the page is removed from swapcache from under us (with a
-		 * racy try_to_unuse/swapoff) we need an additional reference
-		 * count to avoid reading garbage from page_private(page) above.
-		 * If the WARN_ON triggers during a swapoff it maybe the race
-		 * condition and it's harmless. However if it triggers without
-		 * swapoff it signals a problem.
-		 */
-		WARN_ON(page_count(page) <= 1);
-
-		bdi = bdev->bd_inode->i_mapping->backing_dev_info;
-		blk_run_backing_dev(bdi, page);
-	}
-	up_read(&swap_unplug_sem);
-}
-
 /*
  * swapon tell device that all the old swap contents can be discarded,
  * to allow the swap device to optimize its wear-levelling.
@@ -1643,10 +1610,6 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 		goto out_dput;
 	}
 
-	/* wait for any unplug function to finish */
-	down_write(&swap_unplug_sem);
-	up_write(&swap_unplug_sem);
-
 	destroy_swap_extents(p);
 	if (p->flags & SWP_CONTINUED)
 		free_swap_count_continuations(p);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 17497d0cd8b..251bed73ac0 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -358,7 +358,7 @@ static int may_write_to_queue(struct backing_dev_info *bdi,
 static void handle_write_error(struct address_space *mapping,
 				struct page *page, int error)
 {
-	lock_page_nosync(page);
+	lock_page(page);
 	if (page_mapping(page) == mapping)
 		mapping_set_error(mapping, error);
 	unlock_page(page);
-- 
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