137 files changed, 606 insertions, 1533 deletions

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 74d496ccf4d..e1fcf7a2466 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -27,6 +27,7 @@
 #include <linux/writeback.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/fault-inject.h>
+#include <linux/list_sort.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/block.h>
@@ -198,135 +199,43 @@ void blk_dump_rq_flags(struct request *rq, char *msg)
 EXPORT_SYMBOL(blk_dump_rq_flags);
 
 /*
- * "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)
+ * 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)
 {
-        WARN_ON(!irqs_disabled());
-
         /*
-         * don't plug a stopped queue, it must be paired with blk_start_queue()
-         * which will restart the queueing
+         * If the current process is plugged and has barriers submitted,
+         * we will livelock if we don't unplug first.
          */
-        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;
+        blk_flush_plug(current);
 }
-EXPORT_SYMBOL(blk_remove_plug);
 
-/*
- * remove the plug and let it rip..
- */
-void __generic_unplug_device(struct request_queue *q)
+static void blk_delay_work(struct work_struct *work)
 {
-        if (unlikely(blk_queue_stopped(q)))
-                return;
-        if (!blk_remove_plug(q) && !blk_queue_nonrot(q))
-                return;
+        struct request_queue *q;
 
-        q->request_fn(q);
+        q = container_of(work, struct request_queue, delay_work.work);
+        spin_lock_irq(q->queue_lock);
+        __blk_run_queue(q, false);
+        spin_unlock_irq(q->queue_lock);
 }
 
 /**
- * generic_unplug_device - fire a request queue
- * @q:    The &struct request_queue in question
+ * blk_delay_queue - restart queueing after defined interval
+ * @q:          The &struct request_queue in question
+ * @msecs:      Delay in msecs
  *
  * 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)
+ *   Sometimes queueing needs to be postponed for a little while, to allow
+ *   resources to come back. This function will make sure that queueing is
+ *   restarted around the specified time.
+ */
+void blk_delay_queue(struct request_queue *q, unsigned long msecs)
 {
-        /*
-         * devices don't necessarily have an ->unplug_fn defined
-         */
-        if (q->unplug_fn) {
-                trace_block_unplug_io(q);
-                q->unplug_fn(q);
-        }
+        schedule_delayed_work(&q->delay_work, msecs_to_jiffies(msecs));
 }
-EXPORT_SYMBOL(blk_unplug);
+EXPORT_SYMBOL(blk_delay_queue);
 
 /**
  * blk_start_queue - restart a previously stopped queue
@@ -362,7 +271,7 @@ 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);
 }
 EXPORT_SYMBOL(blk_stop_queue);
@@ -387,9 +296,9 @@ 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);
+        cancel_delayed_work_sync(&q->delay_work);
+        queue_sync_plugs(q);
 }
 EXPORT_SYMBOL(blk_sync_queue);
 
@@ -405,14 +314,9 @@ EXPORT_SYMBOL(blk_sync_queue);
  */
 void __blk_run_queue(struct request_queue *q, bool force_kblockd)
 {
-        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.
@@ -420,10 +324,8 @@ void __blk_run_queue(struct request_queue *q, bool force_kblockd)
         if (!force_kblockd && !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);
 
@@ -517,8 +419,6 @@ 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;
@@ -538,13 +438,12 @@ 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);
 
@@ -639,7 +538,6 @@ 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;
 
         /* Override internal queue lock with supplied lock pointer */
@@ -677,6 +575,8 @@ int blk_get_queue(struct request_queue *q)
 
 static inline void blk_free_request(struct request_queue *q, struct request *rq)
 {
+        BUG_ON(rq->cmd_flags & REQ_ON_PLUG);
+
         if (rq->cmd_flags & REQ_ELVPRIV)
                 elv_put_request(q, rq);
         mempool_free(rq, q->rq.rq_pool);
@@ -898,8 +798,8 @@ 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.
  */
@@ -920,7 +820,6 @@ 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();
 
@@ -1042,6 +941,13 @@ void blk_requeue_request(struct request_queue *q, struct request *rq)
 }
 EXPORT_SYMBOL(blk_requeue_request);
 
+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);
+}
+
 /**
  * blk_insert_request - insert a special request into a request queue
  * @q:          request queue where request should be inserted
@@ -1084,8 +990,7 @@ void blk_insert_request(struct request_queue *q, struct request *rq,
         if (blk_rq_tagged(rq))
                 blk_queue_end_tag(q, rq);
 
-        drive_stat_acct(rq, 1);
-        __elv_add_request(q, rq, where, 0);
+        add_acct_request(q, rq, where);
         __blk_run_queue(q, false);
         spin_unlock_irqrestore(q->queue_lock, flags);
 }
@@ -1206,6 +1111,113 @@ void blk_add_request_payload(struct request *rq, struct page *page,
 }
 EXPORT_SYMBOL_GPL(blk_add_request_payload);
 
+static bool bio_attempt_back_merge(struct request_queue *q, struct request *req,
+                                   struct bio *bio)
+{
+        const int ff = bio->bi_rw & REQ_FAILFAST_MASK;
+
+        /*
+         * Debug stuff, kill later
+         */
+        if (!rq_mergeable(req)) {
+                blk_dump_rq_flags(req, "back");
+                return false;
+        }
+
+        if (!ll_back_merge_fn(q, req, bio))
+                return false;
+
+        trace_block_bio_backmerge(q, bio);
+
+        if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
+                blk_rq_set_mixed_merge(req);
+
+        req->biotail->bi_next = bio;
+        req->biotail = bio;
+        req->__data_len += bio->bi_size;
+        req->ioprio = ioprio_best(req->ioprio, bio_prio(bio));
+
+        drive_stat_acct(req, 0);
+        return true;
+}
+
+static bool bio_attempt_front_merge(struct request_queue *q,
+                                    struct request *req, struct bio *bio)
+{
+        const int ff = bio->bi_rw & REQ_FAILFAST_MASK;
+        sector_t sector;
+
+        /*
+         * Debug stuff, kill later
+         */
+        if (!rq_mergeable(req)) {
+                blk_dump_rq_flags(req, "front");
+                return false;
+        }
+
+        if (!ll_front_merge_fn(q, req, bio))
+                return false;
+
+        trace_block_bio_frontmerge(q, bio);
+
+        if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
+                blk_rq_set_mixed_merge(req);
+
+        sector = bio->bi_sector;
+
+        bio->bi_next = req->bio;
+        req->bio = bio;
+
+        /*
+         * may not be valid. if the low level driver said
+         * it didn't need a bounce buffer then it better
+         * not touch req->buffer either...
+         */
+        req->buffer = bio_data(bio);
+        req->__sector = bio->bi_sector;
+        req->__data_len += bio->bi_size;
+        req->ioprio = ioprio_best(req->ioprio, bio_prio(bio));
+
+        drive_stat_acct(req, 0);
+        return true;
+}
+
+/*
+ * Attempts to merge with the plugged list in the current process. Returns
+ * true if merge was succesful, otherwise false.
+ */
+static bool attempt_plug_merge(struct task_struct *tsk, struct request_queue *q,
+                               struct bio *bio)
+{
+        struct blk_plug *plug;
+        struct request *rq;
+        bool ret = false;
+
+        plug = tsk->plug;
+        if (!plug)
+                goto out;
+
+        list_for_each_entry_reverse(rq, &plug->list, queuelist) {
+                int el_ret;
+
+                if (rq->q != q)
+                        continue;
+
+                el_ret = elv_try_merge(rq, bio);
+                if (el_ret == ELEVATOR_BACK_MERGE) {
+                        ret = bio_attempt_back_merge(q, rq, bio);
+                        if (ret)
+                                break;
+                } else if (el_ret == ELEVATOR_FRONT_MERGE) {
+                        ret = bio_attempt_front_merge(q, rq, bio);
+                        if (ret)
+                                break;
+                }
+        }
+out:
+        return ret;
+}
+
 void init_request_from_bio(struct request *req, struct bio *bio)
 {
         req->cpu = bio->bi_comp_cpu;
@@ -1221,26 +1233,12 @@ void init_request_from_bio(struct request *req, struct bio *bio)
         blk_rq_bio_prep(req->q, req, bio);
 }
 
-/*
- * Only disabling plugging for non-rotational devices if it does tagging
- * as well, otherwise we do need the proper merging
- */
-static inline bool queue_should_plug(struct request_queue *q)
-{
-        return !(blk_queue_nonrot(q) && blk_queue_tagged(q));
-}
-
 static int __make_request(struct request_queue *q, struct bio *bio)
 {
-        struct request *req;
-        int el_ret;
-        unsigned int bytes = bio->bi_size;
-        const unsigned short prio = bio_prio(bio);
         const bool sync = !!(bio->bi_rw & REQ_SYNC);
-        const bool unplug = !!(bio->bi_rw & REQ_UNPLUG);
-        const unsigned long ff = bio->bi_rw & REQ_FAILFAST_MASK;
-        int where = ELEVATOR_INSERT_SORT;
-        int rw_flags;
+        struct blk_plug *plug;
+        int el_ret, rw_flags, where = ELEVATOR_INSERT_SORT;
+        struct request *req;
 
         /*
          * low level driver can indicate that it wants pages above a
@@ -1249,78 +1247,36 @@ static int __make_request(struct request_queue *q, struct bio *bio)
          */
         blk_queue_bounce(q, &bio);
 
-        spin_lock_irq(q->queue_lock);
-
         if (bio->bi_rw & (REQ_FLUSH | REQ_FUA)) {
+                spin_lock_irq(q->queue_lock);
                 where = ELEVATOR_INSERT_FLUSH;
                 goto get_rq;
         }
 
-        if (elv_queue_empty(q))
-                goto get_rq;
-
-        el_ret = elv_merge(q, &req, bio);
-        switch (el_ret) {
-        case ELEVATOR_BACK_MERGE:
-                BUG_ON(!rq_mergeable(req));
-
-                if (!ll_back_merge_fn(q, req, bio))
-                        break;
-
-                trace_block_bio_backmerge(q, bio);
-
-                if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
-                        blk_rq_set_mixed_merge(req);
-
-                req->biotail->bi_next = bio;
-                req->biotail = bio;
-                req->__data_len += bytes;
-                req->ioprio = ioprio_best(req->ioprio, prio);
-                if (!blk_rq_cpu_valid(req))
-                        req->cpu = bio->bi_comp_cpu;
-                drive_stat_acct(req, 0);
-                elv_bio_merged(q, req, bio);
-                if (!attempt_back_merge(q, req))
-                        elv_merged_request(q, req, el_ret);
+        /*
+         * Check if we can merge with the plugged list before grabbing
+         * any locks.
+         */
+        if (attempt_plug_merge(current, q, bio))
                 goto out;
 
-        case ELEVATOR_FRONT_MERGE:
-                BUG_ON(!rq_mergeable(req));
-
-                if (!ll_front_merge_fn(q, req, bio))
-                        break;
-
-                trace_block_bio_frontmerge(q, bio);
+        spin_lock_irq(q->queue_lock);
 
-                if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff) {
-                        blk_rq_set_mixed_merge(req);
-                        req->cmd_flags &= ~REQ_FAILFAST_MASK;
-                        req->cmd_flags |= ff;
+        el_ret = elv_merge(q, &req, bio);
+        if (el_ret == ELEVATOR_BACK_MERGE) {
+                BUG_ON(req->cmd_flags & REQ_ON_PLUG);
+                if (bio_attempt_back_merge(q, req, bio)) {
+                        if (!attempt_back_merge(q, req))
+                                elv_merged_request(q, req, el_ret);
+                        goto out_unlock;
+                }
+        } else if (el_ret == ELEVATOR_FRONT_MERGE) {
+                BUG_ON(req->cmd_flags & REQ_ON_PLUG);
+                if (bio_attempt_front_merge(q, req, bio)) {
+                        if (!attempt_front_merge(q, req))
+                                elv_merged_request(q, req, el_ret);
+                        goto out_unlock;
                 }
-
-                bio->bi_next = req->bio;
-                req->bio = bio;
-
-                /*
-                 * may not be valid. if the low level driver said
-                 * it didn't need a bounce buffer then it better
-                 * not touch req->buffer either...
-                 */
-                req->buffer = bio_data(bio);
-                req->__sector = bio->bi_sector;
-                req->__data_len += bytes;
-                req->ioprio = ioprio_best(req->ioprio, prio);
-                if (!blk_rq_cpu_valid(req))
-                        req->cpu = bio->bi_comp_cpu;
-                drive_stat_acct(req, 0);
-                elv_bio_merged(q, req, bio);
-                if (!attempt_front_merge(q, req))
-                        elv_merged_request(q, req, el_ret);
-                goto out;
-
-        /* ELV_NO_MERGE: elevator says don't/can't merge. */
-        default:
-                ;
         }
 
 get_rq:
@@ -1347,20 +1303,35 @@ get_rq:
          */
         init_request_from_bio(req, bio);
 
-        spin_lock_irq(q->queue_lock);
         if (test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags) ||
-            bio_flagged(bio, BIO_CPU_AFFINE))
-                req->cpu = blk_cpu_to_group(smp_processor_id());
-        if (queue_should_plug(q) && elv_queue_empty(q))
-                blk_plug_device(q);
-
-        /* insert the request into the elevator */
-        drive_stat_acct(req, 1);
-        __elv_add_request(q, req, where, 0);
+            bio_flagged(bio, BIO_CPU_AFFINE)) {
+                req->cpu = blk_cpu_to_group(get_cpu());
+                put_cpu();
+        }
+
+        plug = current->plug;
+        if (plug) {
+                if (!plug->should_sort && !list_empty(&plug->list)) {
+                        struct request *__rq;
+
+                        __rq = list_entry_rq(plug->list.prev);
+                        if (__rq->q != q)
+                                plug->should_sort = 1;
+                }
+                /*
+                 * Debug flag, kill later
+                 */
+                req->cmd_flags |= REQ_ON_PLUG;
+                list_add_tail(&req->queuelist, &plug->list);
+                drive_stat_acct(req, 1);
+        } else {
+                spin_lock_irq(q->queue_lock);
+                add_acct_request(q, req, where);
+                __blk_run_queue(q, false);
+out_unlock:
+                spin_unlock_irq(q->queue_lock);
+        }
 out:
-        if (unplug || !queue_should_plug(q))
-                __generic_unplug_device(q);
-        spin_unlock_irq(q->queue_lock);
         return 0;
 }
 
@@ -1763,9 +1734,7 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq)
          */
         BUG_ON(blk_queued_rq(rq));
 
-        drive_stat_acct(rq, 1);
-        __elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 0);
-
+        add_acct_request(q, rq, ELEVATOR_INSERT_BACK);
         spin_unlock_irqrestore(q->queue_lock, flags);
 
         return 0;
@@ -2643,6 +2612,113 @@ int kblockd_schedule_work(struct request_queue *q, struct work_struct *work)
 }
 EXPORT_SYMBOL(kblockd_schedule_work);
 
+int kblockd_schedule_delayed_work(struct request_queue *q,
+                        struct delayed_work *dwork, unsigned long delay)
+{
+        return queue_delayed_work(kblockd_workqueue, dwork, delay);
+}
+EXPORT_SYMBOL(kblockd_schedule_delayed_work);
+
+#define PLUG_MAGIC      0x91827364
+
+void blk_start_plug(struct blk_plug *plug)
+{
+        struct task_struct *tsk = current;
+
+        plug->magic = PLUG_MAGIC;
+        INIT_LIST_HEAD(&plug->list);
+        plug->should_sort = 0;
+
+        /*
+         * If this is a nested plug, don't actually assign it. It will be
+         * flushed on its own.
+         */
+        if (!tsk->plug) {
+                /*
+                 * Store ordering should not be needed here, since a potential
+                 * preempt will imply a full memory barrier
+                 */
+                tsk->plug = plug;
+        }
+}
+EXPORT_SYMBOL(blk_start_plug);
+
+static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b)
+{
+        struct request *rqa = container_of(a, struct request, queuelist);
+        struct request *rqb = container_of(b, struct request, queuelist);
+
+        return !(rqa->q == rqb->q);
+}
+
+static void flush_plug_list(struct blk_plug *plug)
+{
+        struct request_queue *q;
+        unsigned long flags;
+        struct request *rq;
+
+        BUG_ON(plug->magic != PLUG_MAGIC);
+
+        if (list_empty(&plug->list))
+                return;
+
+        if (plug->should_sort)
+                list_sort(NULL, &plug->list, plug_rq_cmp);
+
+        q = NULL;
+        local_irq_save(flags);
+        while (!list_empty(&plug->list)) {
+                rq = list_entry_rq(plug->list.next);
+                list_del_init(&rq->queuelist);
+                BUG_ON(!(rq->cmd_flags & REQ_ON_PLUG));
+                BUG_ON(!rq->q);
+                if (rq->q != q) {
+                        if (q) {
+                                __blk_run_queue(q, false);
+                                spin_unlock(q->queue_lock);
+                        }
+                        q = rq->q;
+                        spin_lock(q->queue_lock);
+                }
+                rq->cmd_flags &= ~REQ_ON_PLUG;
+
+                /*
+                 * rq is already accounted, so use raw insert
+                 */
+                __elv_add_request(q, rq, ELEVATOR_INSERT_SORT);
+        }
+
+        if (q) {
+                __blk_run_queue(q, false);
+                spin_unlock(q->queue_lock);
+        }
+
+        BUG_ON(!list_empty(&plug->list));
+        local_irq_restore(flags);
+}
+
+static void __blk_finish_plug(struct task_struct *tsk, struct blk_plug *plug)
+{
+        flush_plug_list(plug);
+
+        if (plug == tsk->plug)
+                tsk->plug = NULL;
+}
+
+void blk_finish_plug(struct blk_plug *plug)
+{
+        if (plug)
+                __blk_finish_plug(current, plug);
+}
+EXPORT_SYMBOL(blk_finish_plug);
+
+void __blk_flush_plug(struct task_struct *tsk, struct blk_plug *plug)
+{
+        __blk_finish_plug(tsk, plug);
+        tsk->plug = plug;
+}
+EXPORT_SYMBOL(__blk_flush_plug);
+
 int __init blk_dev_init(void)
 {
         BUILD_BUG_ON(__REQ_NR_BITS > 8 *
diff --git a/block/blk-exec.c b/block/blk-exec.c
index cf1456a02ac..7482b7fa863 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, false);
         /* 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 0bd8c9c5d6e..93d5fd8e51e 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;
 
@@ -218,7 +217,7 @@ static void flush_end_io(struct request *flush_rq, int error)
          * from request completion path and calling directly into
          * request_fn may confuse the driver.  Always use kblockd.
          */
-        if (queued && was_empty)
+        if (queued)
                 __blk_run_queue(q, true);
 }
 
@@ -269,13 +268,12 @@ static bool blk_kick_flush(struct request_queue *q)
 static void flush_data_end_io(struct request *rq, int error)
 {
         struct request_queue *q = rq->q;
-        bool was_empty = elv_queue_empty(q);
 
         /*
          * After populating an empty queue, kick it to avoid stall.  Read
          * the comment in flush_end_io().
          */
-        if (blk_flush_complete_seq(rq, REQ_FSEQ_DATA, error) && was_empty)
+        if (blk_flush_complete_seq(rq, REQ_FSEQ_DATA, error))
                 __blk_run_queue(q, true);
 }
 
diff --git a/block/blk-settings.c b/block/blk-settings.c
index df649fa59de..1fa76929359 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 32dd3e4b041..37abbfc6859 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -768,6 +768,7 @@ static int throtl_dispatch(struct request_queue *q)
         unsigned int nr_disp = 0;
         struct bio_list bio_list_on_stack;
         struct bio *bio;
+        struct blk_plug plug;
 
         spin_lock_irq(q->queue_lock);
 
@@ -796,9 +797,10 @@ out:
          * immediate dispatch
          */
         if (nr_disp) {
+                blk_start_plug(&plug);
                 while((bio = bio_list_pop(&bio_list_on_stack)))
                         generic_make_request(bio);
-                blk_unplug(q);
+                blk_finish_plug(&plug);
         }
         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 9697053f80b..c826ef81c67 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -500,13 +500,6 @@ 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
@@ -4080,7 +4073,6 @@ 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 fabf3675c91..542ce826b40 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;
 
@@ -617,21 +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);
@@ -677,25 +670,17 @@ 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);
+
         if (rq->cmd_flags & REQ_SOFTBARRIER) {
                 /* barriers are scheduling boundary, update end_sector */
                 if (rq->cmd_type == REQ_TYPE_FS ||
@@ -707,38 +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..aca302492ff 100644
--- a/drivers/block/drbd/drbd_actlog.c
+++ b/drivers/block/drbd/drbd_actlog.c
@@ -80,7 +80,7 @@ static int _drbd_md_sync_page_io(struct drbd_conf *mdev,
 
         if ((rw & WRITE) && !test_bit(MD_NO_FUA, &mdev->flags))
                 rw |= REQ_FUA;
-        rw |= REQ_UNPLUG | REQ_SYNC;
+        rw |= REQ_SYNC;
 
         bio = bio_alloc(GFP_NOIO, 1);
         bio->bi_bdev = bdev->md_bdev;
@@ -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..b0bd27dfc1e 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -377,7 +377,7 @@ union p_header {
 #define DP_HARDBARRIER        1 /* depricated */
 #define DP_RW_SYNC            2 /* equals REQ_SYNC    */
 #define DP_MAY_SET_IN_SYNC    4
-#define DP_UNPLUG             8 /* equals REQ_UNPLUG  */
+#define DP_UNPLUG             8 /* not used anymore   */
 #define DP_FUA               16 /* equals REQ_FUA     */
 #define DP_FLUSH             32 /* equals REQ_FLUSH   */
 #define DP_DISCARD           64 /* equals REQ_DISCARD */
@@ -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..8a43ce0edee 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2477,12 +2477,11 @@ static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw)
 {
         if (mdev->agreed_pro_version >= 95)
                 return  (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) |
-                        (bi_rw & REQ_UNPLUG ? DP_UNPLUG : 0) |
                         (bi_rw & REQ_FUA ? DP_FUA : 0) |
                         (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) |
                         (bi_rw & REQ_DISCARD ? DP_DISCARD : 0);
         else
-                return bi_rw & (REQ_SYNC | REQ_UNPLUG) ? DP_RW_SYNC : 0;
+                return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0;
 }
 
 /* Used to send write requests
@@ -2719,35 +2718,6 @@ 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 +3192,7 @@ 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..8e68be939de 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);
         }
@@ -1111,8 +1100,6 @@ next_bio:
         /* > e->sector, unless this is the first bio */
         bio->bi_sector = sector;
         bio->bi_bdev = mdev->ldev->backing_bdev;
-        /* we special case some flags in the multi-bio case, see below
-         * (REQ_UNPLUG) */
         bio->bi_rw = rw;
         bio->bi_private = e;
         bio->bi_end_io = drbd_endio_sec;
@@ -1141,13 +1128,8 @@ next_bio:
                 bios = bios->bi_next;
                 bio->bi_next = NULL;
 
-                /* strip off REQ_UNPLUG unless it is the last bio */
-                if (bios)
-                        bio->bi_rw &= ~REQ_UNPLUG;
-
                 drbd_generic_make_request(mdev, fault_type, bio);
         } while (bios);
-        maybe_kick_lo(mdev);
         return 0;
 
 fail:
@@ -1167,9 +1149,6 @@ 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);
 
@@ -1636,12 +1615,11 @@ static unsigned long write_flags_to_bio(struct drbd_conf *mdev, u32 dpf)
 {
         if (mdev->agreed_pro_version >= 95)
                 return  (dpf & DP_RW_SYNC ? REQ_SYNC : 0) |
-                        (dpf & DP_UNPLUG ? REQ_UNPLUG : 0) |
                         (dpf & DP_FUA ? REQ_FUA : 0) |
                         (dpf & DP_FLUSH ? REQ_FUA : 0) |
                         (dpf & DP_DISCARD ? REQ_DISCARD : 0);
         else
-                return dpf & DP_RW_SYNC ? (REQ_SYNC | REQ_UNPLUG) : 0;
+                return dpf & DP_RW_SYNC ? REQ_SYNC : 0;
 }
 
 /* mirrored write */
@@ -3556,9 +3534,6 @@ 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 3851dbc03e0..301d7a9a41a 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -3838,7 +3838,6 @@ 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 79c3079a620..a076a14ca72 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -540,17 +540,6 @@ 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;
@@ -917,7 +906,6 @@ 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);
@@ -1019,7 +1007,6 @@ 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 a077db27b7c..07a382eaf0a 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 9b102abe209..031ca720d92 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;
@@ -897,7 +884,6 @@ 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-cd.c b/drivers/ide/ide-cd.c
index a2e29099ee0..fd1e1179913 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -258,17 +258,10 @@ static int ide_cd_breathe(ide_drive_t *drive, struct request *rq)
         if (time_after(jiffies, info->write_timeout))
                 return 0;
         else {
-                struct request_queue *q = drive->queue;
-                unsigned long flags;
-
                 /*
-                 * take a breather relying on the unplug timer to kick us again
+                 * take a breather
                  */
-
-                spin_lock_irqsave(q->queue_lock, flags);
-                blk_plug_device(q);
-                spin_unlock_irqrestore(q->queue_lock, flags);
-
+                blk_delay_queue(drive->queue, 1);
                 return 1;
         }
 }
@@ -1514,8 +1507,6 @@ static int ide_cdrom_setup(ide_drive_t *drive)
         blk_queue_dma_alignment(q, 31);
         blk_queue_update_dma_pad(q, 15);
 
-        q->unplug_delay = max((1 * HZ) / 1000, 1);
-
         drive->dev_flags |= IDE_DFLAG_MEDIA_CHANGED;
         drive->atapi_flags = IDE_AFLAG_NO_EJECT | ide_cd_flags(id);
 
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..ca203cb23f3 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -347,7 +347,7 @@ static void write_page(struct bitmap *bitmap, struct page *page, int wait)
                         atomic_inc(&bitmap->pending_writes);
                         set_buffer_locked(bh);
                         set_buffer_mapped(bh);
-                        submit_bh(WRITE | REQ_UNPLUG | REQ_SYNC, bh);
+                        submit_bh(WRITE | REQ_SYNC, bh);
                         bh = bh->b_this_page;
                 }
 
@@ -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-io.c b/drivers/md/dm-io.c
index 136d4f71a11..76a5af00a26 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -352,7 +352,7 @@ static void dispatch_io(int rw, unsigned int num_regions,
         BUG_ON(num_regions > DM_IO_MAX_REGIONS);
 
         if (sync)
-                rw |= REQ_SYNC | REQ_UNPLUG;
+                rw |= REQ_SYNC;
 
         /*
          * For multiple regions we need to be careful to rewind
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
index 924f5f0084c..1bb73a13ca4 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;
@@ -386,16 +354,10 @@ 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 {
-                if (job->num_dests > 1)
-                        io_req.bi_rw |= REQ_UNPLUG;
+        else
                 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 +428,7 @@ 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 +436,12 @@ 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 +622,6 @@ 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 0ed7f6bc2a7..338804f8fb3 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;
@@ -224,7 +208,6 @@ 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 818313e277e..86ba66c0b28 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -780,8 +780,7 @@ void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
         bio->bi_end_io = super_written;
 
         atomic_inc(&mddev->pending_writes);
-        submit_bio(REQ_WRITE | REQ_SYNC | REQ_UNPLUG | REQ_FLUSH | REQ_FUA,
-                   bio);
+        submit_bio(REQ_WRITE | REQ_SYNC | REQ_FLUSH | REQ_FUA, bio);
 }
 
 void md_super_wait(mddev_t *mddev)
@@ -809,7 +808,7 @@ int sync_page_io(mdk_rdev_t *rdev, sector_t sector, int size,
         struct completion event;
         int ret;
 
-        rw |= REQ_SYNC | REQ_UNPLUG;
+        rw |= REQ_SYNC;
 
         bio->bi_bdev = (metadata_op && rdev->meta_bdev) ?
                 rdev->meta_bdev : rdev->bdev;
@@ -4817,7 +4816,6 @@ 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' */
@@ -6692,8 +6690,6 @@ 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);
 }
@@ -6876,7 +6872,6 @@ 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;
@@ -6952,7 +6947,6 @@ 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
@@ -6971,8 +6965,6 @@ 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 3a62d440e27..5e694b151c3 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;
@@ -517,7 +487,6 @@ 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 c0ac457f121..95916fd6394 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 06cd712807d..8f34ad5c478 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;
@@ -580,23 +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);
-                /* Only take the spinlock to quiet a warning */
-                spin_lock(conf->mddev->queue->queue_lock);
-                blk_remove_plug(conf->mddev->queue);
-                spin_unlock(conf->mddev->queue->queue_lock);
                 spin_unlock_irq(&conf->device_lock);
                 /* flush any pending bitmap writes to
                  * disk before proceeding w/ I/O */
@@ -608,10 +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....
@@ -643,8 +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++;
@@ -652,8 +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);
 }
@@ -675,7 +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++;
@@ -712,7 +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)
@@ -962,7 +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_unlocked(mddev->queue);
                 spin_unlock_irqrestore(&conf->device_lock, flags);
         }
         r1_bio_write_done(r1_bio, bio->bi_vcnt, behind_pages, behind_pages != NULL);
@@ -971,7 +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;
@@ -1561,7 +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);
@@ -1569,7 +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)) {
@@ -1583,10 +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
@@ -1636,14 +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);
 }
 
 
@@ -2066,7 +2015,6 @@ 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 747d061d8e0..c0d0f5f7e40 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;
@@ -649,23 +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);
-                /* Spinlock only taken to quiet a warning */
-                spin_lock(conf->mddev->queue->queue_lock);
-                blk_remove_plug(conf->mddev->queue);
-                spin_unlock(conf->mddev->queue->queue_lock);
                 spin_unlock_irq(&conf->device_lock);
                 /* flush any pending bitmap writes to disk
                  * before proceeding w/ I/O */
@@ -677,11 +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.
@@ -711,8 +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++;
@@ -720,8 +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);
 }
@@ -742,7 +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++;
@@ -779,7 +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);
 }
 
@@ -974,7 +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_unlocked(mddev->queue);
                 spin_unlock_irqrestore(&conf->device_lock, flags);
         }
 
@@ -991,7 +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;
@@ -1684,7 +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);
@@ -1692,7 +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)) {
@@ -1706,13 +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.
@@ -1759,14 +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);
 }
 
 
@@ -2377,7 +2326,6 @@ 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 78536fdbd87..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");
 }
@@ -5204,7 +5159,7 @@ 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->unplug_fn = raid5_unplug_queue;
+                mddev->queue->queue_lock = &conf->device_lock;
 
                 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 f81c25d4a12..47ec5bc0ed2 100644
--- a/drivers/message/i2o/i2o_block.c
+++ b/drivers/message/i2o/i2o_block.c
@@ -897,11 +897,7 @@ 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 ad843163601..83cea9a55e2 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_lib.c b/drivers/scsi/scsi_lib.c
index fb2bb35c62c..bf80a4c5a48 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -67,6 +67,13 @@ static struct scsi_host_sg_pool scsi_sg_pools[] = {
 
 struct kmem_cache *scsi_sdb_cache;
 
+/*
+ * When to reinvoke queueing after a resource shortage. It's 3 msecs to
+ * not change behaviour from the previous unplug mechanism, experimentation
+ * may prove this needs changing.
+ */
+#define SCSI_QUEUE_DELAY        3
+
 static void scsi_run_queue(struct request_queue *q);
 
 /*
@@ -149,14 +156,7 @@ static int __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, int unbusy)
         /*
          * Requeue this command.  It will go before all other commands
          * that are already in the queue.
-         *
-         * NOTE: there is magic here about the way the queue is plugged if
-         * we have no outstanding commands.
-         * 
-         * Although we *don't* plug the queue, we call the request
-         * function.  The SCSI request function detects the blocked condition
-         * and plugs the queue appropriately.
-         */
+         */
         spin_lock_irqsave(q->queue_lock, flags);
         blk_requeue_request(q, cmd->request);
         spin_unlock_irqrestore(q->queue_lock, flags);
@@ -1194,11 +1194,11 @@ int scsi_prep_return(struct request_queue *q, struct request *req, int ret)
         case BLKPREP_DEFER:
                 /*
                  * If we defer, the blk_peek_request() returns NULL, but the
-                 * queue must be restarted, so we plug here if no returning
-                 * command will automatically do that.
+                 * queue must be restarted, so we schedule a callback to happen
+                 * shortly.
                  */
                 if (sdev->device_busy == 0)
-                        blk_plug_device(q);
+                        blk_delay_queue(q, SCSI_QUEUE_DELAY);
                 break;
         default:
                 req->cmd_flags |= REQ_DONTPREP;
@@ -1237,7 +1237,7 @@ static inline int scsi_dev_queue_ready(struct request_queue *q,
                                    sdev_printk(KERN_INFO, sdev,
                                    "unblocking device at zero depth\n"));
                 } else {
-                        blk_plug_device(q);
+                        blk_delay_queue(q, SCSI_QUEUE_DELAY);
                         return 0;
                 }
         }
@@ -1467,7 +1467,7 @@ static void scsi_request_fn(struct request_queue *q)
          * the host is no longer able to accept any more requests.
          */
         shost = sdev->host;
-        while (!blk_queue_plugged(q)) {
+        for (;;) {
                 int rtn;
                 /*
                  * get next queueable request.  We do this early to make sure
@@ -1546,15 +1546,8 @@ static void scsi_request_fn(struct request_queue *q)
                  */
                 rtn = scsi_dispatch_cmd(cmd);
                 spin_lock_irq(q->queue_lock);
-                if(rtn) {
-                        /* we're refusing the command; because of
-                         * the way locks get dropped, we need to 
-                         * check here if plugging is required */
-                        if(sdev->device_busy == 0)
-                                blk_plug_device(q);
-
-                        break;
-                }
+                if (rtn)
+                        goto out_delay;
         }
 
         goto out;
@@ -1573,9 +1566,10 @@ static void scsi_request_fn(struct request_queue *q)
         spin_lock_irq(q->queue_lock);
         blk_requeue_request(q, req);
         sdev->device_busy--;
-        if(sdev->device_busy == 0)
-                blk_plug_device(q);
- out:
+out_delay:
+        if (sdev->device_busy == 0)
+                blk_delay_queue(q, SCSI_QUEUE_DELAY);
+out:
         /* must be careful here...if we trigger the ->remove() function
          * we cannot be holding the q lock */
         spin_unlock_irq(q->queue_lock);
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
index 5c3ccfc6b62..2941d2d92c9 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 26869cde395..a936b7fe4f6 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -34,8 +34,6 @@
 #include <linux/security.h>
 #include <linux/eventfd.h>
 #include <linux/blkdev.h>
-#include <linux/mempool.h>
-#include <linux/hash.h>
 #include <linux/compat.h>
 
 #include <asm/kmap_types.h>
@@ -65,14 +63,6 @@ static DECLARE_WORK(fput_work, aio_fput_routine);
 static DEFINE_SPINLOCK(fput_lock);
 static LIST_HEAD(fput_head);
 
-#define AIO_BATCH_HASH_BITS     3 /* allocated on-stack, so don't go crazy */
-#define AIO_BATCH_HASH_SIZE     (1 << AIO_BATCH_HASH_BITS)
-struct aio_batch_entry {
-        struct hlist_node list;
-        struct address_space *mapping;
-};
-mempool_t *abe_pool;
-
 static void aio_kick_handler(struct work_struct *);
 static void aio_queue_work(struct kioctx *);
 
@@ -86,8 +76,7 @@ static int __init aio_setup(void)
         kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
 
         aio_wq = create_workqueue("aio");
-        abe_pool = mempool_create_kmalloc_pool(1, sizeof(struct aio_batch_entry));
-        BUG_ON(!aio_wq || !abe_pool);
+        BUG_ON(!aio_wq);
 
         pr_debug("aio_setup: sizeof(struct page) = %d\n", (int)sizeof(struct page));
 
@@ -1525,57 +1514,8 @@ static ssize_t aio_setup_iocb(struct kiocb *kiocb, bool compat)
         return 0;
 }
 
-static void aio_batch_add(struct address_space *mapping,
-                          struct hlist_head *batch_hash)
-{
-        struct aio_batch_entry *abe;
-        struct hlist_node *pos;
-        unsigned bucket;
-
-        bucket = hash_ptr(mapping, AIO_BATCH_HASH_BITS);
-        hlist_for_each_entry(abe, pos, &batch_hash[bucket], list) {
-                if (abe->mapping == mapping)
-                        return;
-        }
-
-        abe = mempool_alloc(abe_pool, GFP_KERNEL);
-
-        /*
-         * we should be using igrab here, but
-         * we don't want to hammer on the global
-         * inode spinlock just to take an extra
-         * reference on a file that we must already
-         * have a reference to.
-         *
-         * When we're called, we always have a reference
-         * on the file, so we must always have a reference
-         * on the inode, so ihold() is safe here.
-         */
-        ihold(mapping->host);
-        abe->mapping = mapping;
-        hlist_add_head(&abe->list, &batch_hash[bucket]);
-        return;
-}
-
-static void aio_batch_free(struct hlist_head *batch_hash)
-{
-        struct aio_batch_entry *abe;
-        struct hlist_node *pos, *n;
-        int i;
-
-        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);
-                }
-        }
-}
-
 static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
-                         struct iocb *iocb, struct hlist_head *batch_hash,
-                         bool compat)
+                         struct iocb *iocb, bool compat)
 {
         struct kiocb *req;
         struct file *file;
@@ -1666,11 +1606,6 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
                         ;
         }
         spin_unlock_irq(&ctx->ctx_lock);
-        if (req->ki_opcode == IOCB_CMD_PREAD ||
-            req->ki_opcode == IOCB_CMD_PREADV ||
-            req->ki_opcode == IOCB_CMD_PWRITE ||
-            req->ki_opcode == IOCB_CMD_PWRITEV)
-                aio_batch_add(file->f_mapping, batch_hash);
 
         aio_put_req(req);       /* drop extra ref to req */
         return 0;
@@ -1687,7 +1622,7 @@ long do_io_submit(aio_context_t ctx_id, long nr,
         struct kioctx *ctx;
         long ret = 0;
         int i;
-        struct hlist_head batch_hash[AIO_BATCH_HASH_SIZE] = { { 0, }, };
+        struct blk_plug plug;
 
         if (unlikely(nr < 0))
                 return -EINVAL;
@@ -1704,6 +1639,8 @@ long do_io_submit(aio_context_t ctx_id, long nr,
                 return -EINVAL;
         }
 
+        blk_start_plug(&plug);
+
         /*
          * AKPM: should this return a partial result if some of the IOs were
          * successfully submitted?
@@ -1722,11 +1659,11 @@ long do_io_submit(aio_context_t ctx_id, long nr,
                         break;
                 }
 
-                ret = io_submit_one(ctx, user_iocb, &tmp, batch_hash, compat);
+                ret = io_submit_one(ctx, user_iocb, &tmp, compat);
                 if (ret)
                         break;
         }
-        aio_batch_free(batch_hash);
+        blk_finish_plug(&plug);
 
         put_ioctx(ctx);
         return i ? i : ret;
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 d42cad2757a..fbe05cbdd69 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1529,7 +1529,6 @@ 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
@@ -1331,82 +1330,6 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 }
 
 /*
- * 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/extent_io.c b/fs/btrfs/extent_io.c
index fd3f172e94e..00497d551e5 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2188,7 +2188,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
         unsigned long nr_written = 0;
 
         if (wbc->sync_mode == WB_SYNC_ALL)
-                write_flags = WRITE_SYNC_PLUG;
+                write_flags = WRITE_SYNC;
         else
                 write_flags = WRITE;
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 0efdb65953c..02438c91792 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7340,7 +7340,6 @@ 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 dd13eb81ee4..9d554e8e658 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;
@@ -2955,7 +2911,7 @@ 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;
@@ -2987,11 +2943,6 @@ 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,
@@ -3047,13 +2998,13 @@ 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;
@@ -3075,7 +3026,7 @@ 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;
@@ -3095,22 +3046,10 @@ 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) {
@@ -3128,7 +3067,7 @@ 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,
@@ -3196,14 +3135,6 @@ 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..42534f67d71 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);
@@ -775,7 +767,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list)
                                  * still in flight on potentially older
                                  * contents.
                                  */
-                                write_dirty_buffer(bh, WRITE_SYNC_PLUG);
+                                write_dirty_buffer(bh, WRITE_SYNC);
 
                                 /*
                                  * Kick off IO for the previous mapping. Note
@@ -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);
                         }
@@ -1614,14 +1602,8 @@ EXPORT_SYMBOL(unmap_underlying_metadata);
  * prevents this contention from occurring.
  *
  * If block_write_full_page() is called with wbc->sync_mode ==
- * WB_SYNC_ALL, the writes are posted using WRITE_SYNC_PLUG; this
- * causes the writes to be flagged as synchronous writes, but the
- * block device queue will NOT be unplugged, since usually many pages
- * will be pushed to the out before the higher-level caller actually
- * waits for the writes to be completed.  The various wait functions,
- * such as wait_on_writeback_range() will ultimately call sync_page()
- * which will ultimately call blk_run_backing_dev(), which will end up
- * unplugging the device queue.
+ * WB_SYNC_ALL, the writes are posted using WRITE_SYNC; this
+ * causes the writes to be flagged as synchronous writes.
  */
 static int __block_write_full_page(struct inode *inode, struct page *page,
                         get_block_t *get_block, struct writeback_control *wbc,
@@ -1634,7 +1616,7 @@ static int __block_write_full_page(struct inode *inode, struct page *page,
         const unsigned blocksize = 1 << inode->i_blkbits;
         int nr_underway = 0;
         int write_op = (wbc->sync_mode == WB_SYNC_ALL ?
-                        WRITE_SYNC_PLUG : WRITE);
+                        WRITE_SYNC : WRITE);
 
         BUG_ON(!PageLocked(page));
 
@@ -3138,17 +3120,6 @@ 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..42608313609 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
@@ -1176,7 +1173,7 @@ __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
         struct dio *dio;
 
         if (rw & WRITE)
-                rw = WRITE_ODIRECT_PLUG;
+                rw = WRITE_ODIRECT;
 
         if (bdev)
                 bdev_blkbits = blksize_bits(bdev_logical_block_size(bdev));
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/ext4/page-io.c b/fs/ext4/page-io.c
index 955cc309142..e2cd90e4bb7 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -310,8 +310,7 @@ static int io_submit_init(struct ext4_io_submit *io,
         io_end->offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh);
 
         io->io_bio = bio;
-        io->io_op = (wbc->sync_mode == WB_SYNC_ALL ?
-                        WRITE_SYNC_PLUG : WRITE);
+        io->io_op = (wbc->sync_mode == WB_SYNC_ALL ?  WRITE_SYNC : WRITE);
         io->io_next_block = bh->b_blocknr;
         return 0;
 }
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/log.c b/fs/gfs2/log.c
index eb01f3575e1..7f1c1120234 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -121,7 +121,7 @@ __acquires(&sdp->sd_log_lock)
                         lock_buffer(bh);
                         if (test_clear_buffer_dirty(bh)) {
                                 bh->b_end_io = end_buffer_write_sync;
-                                submit_bh(WRITE_SYNC_PLUG, bh);
+                                submit_bh(WRITE_SYNC, bh);
                         } else {
                                 unlock_buffer(bh);
                                 brelse(bh);
@@ -647,7 +647,7 @@ static void gfs2_ordered_write(struct gfs2_sbd *sdp)
                 lock_buffer(bh);
                 if (buffer_mapped(bh) && test_clear_buffer_dirty(bh)) {
                         bh->b_end_io = end_buffer_write_sync;
-                        submit_bh(WRITE_SYNC_PLUG, bh);
+                        submit_bh(WRITE_SYNC, bh);
                 } else {
                         unlock_buffer(bh);
                         brelse(bh);
diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index bf33f822058..48b545a1979 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -200,7 +200,7 @@ static void buf_lo_before_commit(struct gfs2_sbd *sdp)
                 }
 
                 gfs2_log_unlock(sdp);
-                submit_bh(WRITE_SYNC_PLUG, bh);
+                submit_bh(WRITE_SYNC, bh);
                 gfs2_log_lock(sdp);
 
                 n = 0;
@@ -210,7 +210,7 @@ static void buf_lo_before_commit(struct gfs2_sbd *sdp)
                         gfs2_log_unlock(sdp);
                         lock_buffer(bd2->bd_bh);
                         bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
-                        submit_bh(WRITE_SYNC_PLUG, bh);
+                        submit_bh(WRITE_SYNC, bh);
                         gfs2_log_lock(sdp);
                         if (++n >= num)
                                 break;
@@ -352,7 +352,7 @@ static void revoke_lo_before_commit(struct gfs2_sbd *sdp)
                 sdp->sd_log_num_revoke--;
 
                 if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) {
-                        submit_bh(WRITE_SYNC_PLUG, bh);
+                        submit_bh(WRITE_SYNC, bh);
 
                         bh = gfs2_log_get_buf(sdp);
                         mh = (struct gfs2_meta_header *)bh->b_data;
@@ -369,7 +369,7 @@ static void revoke_lo_before_commit(struct gfs2_sbd *sdp)
         }
         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 
-        submit_bh(WRITE_SYNC_PLUG, bh);
+        submit_bh(WRITE_SYNC, bh);
 }
 
 static void revoke_lo_before_scan(struct gfs2_jdesc *jd,
@@ -571,7 +571,7 @@ static void gfs2_write_blocks(struct gfs2_sbd *sdp, struct buffer_head *bh,
         ptr = bh_log_ptr(bh);
         
         get_bh(bh);
-        submit_bh(WRITE_SYNC_PLUG, bh);
+        submit_bh(WRITE_SYNC, bh);
         gfs2_log_lock(sdp);
         while(!list_empty(list)) {
                 bd = list_entry(list->next, struct gfs2_bufdata, bd_le.le_list);
@@ -597,7 +597,7 @@ static void gfs2_write_blocks(struct gfs2_sbd *sdp, struct buffer_head *bh,
                 } else {
                         bh1 = gfs2_log_fake_buf(sdp, bd->bd_bh);
                 }
-                submit_bh(WRITE_SYNC_PLUG, bh1);
+                submit_bh(WRITE_SYNC, bh1);
                 gfs2_log_lock(sdp);
                 ptr += 2;
         }
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 939739c7b3f..867b713cba9 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -37,7 +37,7 @@ static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wb
         struct buffer_head *bh, *head;
         int nr_underway = 0;
         int write_op = REQ_META |
-                (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC_PLUG : WRITE);
+                (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE);
 
         BUG_ON(!PageLocked(page));
         BUG_ON(!page_has_buffers(page));
@@ -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/jbd/commit.c b/fs/jbd/commit.c
index 34a4861c14b..66be299acb1 100644
--- a/fs/jbd/commit.c
+++ b/fs/jbd/commit.c
@@ -333,7 +333,7 @@ void journal_commit_transaction(journal_t *journal)
          * instead we rely on sync_buffer() doing the unplug for us.
          */
         if (commit_transaction->t_synchronous_commit)
-                write_op = WRITE_SYNC_PLUG;
+                write_op = WRITE_SYNC;
         spin_lock(&commit_transaction->t_handle_lock);
         while (commit_transaction->t_updates) {
                 DEFINE_WAIT(wait);
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index f3ad1598b20..3da1cc4346d 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -137,9 +137,9 @@ static int journal_submit_commit_record(journal_t *journal,
         if (journal->j_flags & JBD2_BARRIER &&
             !JBD2_HAS_INCOMPAT_FEATURE(journal,
                                        JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT))
-                ret = submit_bh(WRITE_SYNC_PLUG | WRITE_FLUSH_FUA, bh);
+                ret = submit_bh(WRITE_SYNC | WRITE_FLUSH_FUA, bh);
         else
-                ret = submit_bh(WRITE_SYNC_PLUG, bh);
+                ret = submit_bh(WRITE_SYNC, bh);
 
         *cbh = bh;
         return ret;
@@ -369,7 +369,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
          * instead we rely on sync_buffer() doing the unplug for us.
          */
         if (commit_transaction->t_synchronous_commit)
-                write_op = WRITE_SYNC_PLUG;
+                write_op = WRITE_SYNC;
         trace_jbd2_commit_locking(journal, commit_transaction);
         stats.run.rs_wait = commit_transaction->t_max_wait;
         stats.run.rs_locked = jiffies;
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/mpage.c b/fs/mpage.c
index d78455a81ec..0afc809e46e 100644
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -364,6 +364,9 @@ mpage_readpages(struct address_space *mapping, struct list_head *pages,
         sector_t last_block_in_bio = 0;
         struct buffer_head map_bh;
         unsigned long first_logical_block = 0;
+        struct blk_plug plug;
+
+        blk_start_plug(&plug);
 
         map_bh.b_state = 0;
         map_bh.b_size = 0;
@@ -385,6 +388,7 @@ mpage_readpages(struct address_space *mapping, struct list_head *pages,
         BUG_ON(!list_empty(pages));
         if (bio)
                 mpage_bio_submit(READ, bio);
+        blk_finish_plug(&plug);
         return 0;
 }
 EXPORT_SYMBOL(mpage_readpages);
@@ -666,8 +670,11 @@ int
 mpage_writepages(struct address_space *mapping,
                 struct writeback_control *wbc, get_block_t get_block)
 {
+        struct blk_plug plug;
         int ret;
 
+        blk_start_plug(&plug);
+
         if (!get_block)
                 ret = generic_writepages(mapping, wbc);
         else {
@@ -682,6 +689,7 @@ mpage_writepages(struct address_space *mapping,
                 if (mpd.bio)
                         mpage_bio_submit(WRITE, mpd.bio);
         }
+        blk_finish_plug(&plug);
         return ret;
 }
 EXPORT_SYMBOL(mpage_writepages);
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 85f7baa15f5..609cd223eea 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -34,15 +34,10 @@
 #include "page.h"
 #include "btnode.h"
 
-
-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 a0babd2bff6..a649b05f706 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);
         address_space_init_once(&shadow->frozen_data);
-        nilfs_mapping_init(&shadow->frozen_data, bdi, &shadow_map_aops);
+        nilfs_mapping_init(&shadow->frozen_data, bdi);
         address_space_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 a585b35fd6b..4d2a1ee0eb4 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -493,15 +493,14 @@ unsigned nilfs_page_count_clean_buffers(struct page *page,
 }
 
 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 2a00953ebd5..f06b79ad749 100644
--- a/fs/nilfs2/page.h
+++ b/fs/nilfs2/page.h
@@ -62,8 +62,7 @@ int nilfs_copy_dirty_pages(struct address_space *, struct address_space *);
 void nilfs_copy_back_pages(struct address_space *, struct address_space *);
 void nilfs_clear_dirty_pages(struct address_space *);
 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/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c
index 0f83e93935b..2853ff20f85 100644
--- a/fs/nilfs2/segbuf.c
+++ b/fs/nilfs2/segbuf.c
@@ -509,7 +509,7 @@ static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf,
                  * Last BIO is always sent through the following
                  * submission.
                  */
-                rw |= REQ_SYNC | REQ_UNPLUG;
+                rw |= REQ_SYNC;
                 res = nilfs_segbuf_submit_bio(segbuf, &wi, rw);
         }
 
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..6bbb0ee3325 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -413,8 +413,7 @@ xfs_submit_ioend_bio(
         if (xfs_ioend_new_eof(ioend))
                 xfs_mark_inode_dirty(XFS_I(ioend->io_inode));
 
-        submit_bio(wbc->sync_mode == WB_SYNC_ALL ?
-                   WRITE_SYNC_PLUG : WRITE, bio);
+        submit_bio(wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE, bio);
 }
 
 STATIC struct bio *
@@ -1495,7 +1494,6 @@ 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/blk_types.h b/include/linux/blk_types.h
index dddedfc0af8..be50d9e70a7 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -128,7 +128,6 @@ enum rq_flag_bits {
         __REQ_NOIDLE,           /* don't anticipate more IO after this one */
 
         /* bio only flags */
-        __REQ_UNPLUG,           /* unplug the immediately after submission */
         __REQ_RAHEAD,           /* read ahead, can fail anytime */
         __REQ_THROTTLED,        /* This bio has already been subjected to
                                  * throttling rules. Don't do it again. */
@@ -152,6 +151,7 @@ enum rq_flag_bits {
         __REQ_IO_STAT,          /* account I/O stat */
         __REQ_MIXED_MERGE,      /* merge of different types, fail separately */
         __REQ_SECURE,           /* secure discard (used with __REQ_DISCARD) */
+        __REQ_ON_PLUG,          /* on plug list */
         __REQ_NR_BITS,          /* stops here */
 };
 
@@ -171,7 +171,6 @@ enum rq_flag_bits {
          REQ_NOIDLE | REQ_FLUSH | REQ_FUA)
 #define REQ_CLONE_MASK          REQ_COMMON_MASK
 
-#define REQ_UNPLUG              (1 << __REQ_UNPLUG)
 #define REQ_RAHEAD              (1 << __REQ_RAHEAD)
 #define REQ_THROTTLED           (1 << __REQ_THROTTLED)
 
@@ -193,5 +192,6 @@ enum rq_flag_bits {
 #define REQ_IO_STAT             (1 << __REQ_IO_STAT)
 #define REQ_MIXED_MERGE         (1 << __REQ_MIXED_MERGE)
 #define REQ_SECURE              (1 << __REQ_SECURE)
+#define REQ_ON_PLUG             (1 << __REQ_ON_PLUG)
 
 #endif /* __LINUX_BLK_TYPES_H */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 13b75ca6218..91fa428fa2c 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;
@@ -293,12 +291,9 @@ struct request_queue
         struct request          *boundary_rq;
 
         /*
-         * Auto-unplugging state
+         * Delayed queue handling
          */
-        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;
+        struct delayed_work     delay_work;
 
         struct backing_dev_info backing_dev_info;
 
@@ -394,14 +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 */
@@ -479,7 +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)
@@ -674,9 +667,7 @@ 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,
                           unsigned int, void __user *);
@@ -720,7 +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)
 {
@@ -857,7 +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 *);
@@ -865,6 +854,31 @@ struct request_queue *blk_alloc_queue(gfp_t);
 struct request_queue *blk_alloc_queue_node(gfp_t, int);
 extern void blk_put_queue(struct request_queue *);
 
+struct blk_plug {
+        unsigned long magic;
+        struct list_head list;
+        unsigned int should_sort;
+};
+
+extern void blk_start_plug(struct blk_plug *);
+extern void blk_finish_plug(struct blk_plug *);
+extern void __blk_flush_plug(struct task_struct *, struct blk_plug *);
+
+static inline void blk_flush_plug(struct task_struct *tsk)
+{
+        struct blk_plug *plug = tsk->plug;
+
+        if (unlikely(plug))
+                __blk_flush_plug(tsk, plug);
+}
+
+static inline bool blk_needs_flush_plug(struct task_struct *tsk)
+{
+        struct blk_plug *plug = tsk->plug;
+
+        return plug && !list_empty(&plug->list);
+}
+
 /*
  * tag stuff
  */
@@ -1283,6 +1297,23 @@ static inline long nr_blockdev_pages(void)
         return 0;
 }
 
+static inline void blk_start_plug(struct list_head *list)
+{
+}
+
+static inline void blk_finish_plug(struct list_head *list)
+{
+}
+
+static inline void blk_flush_plug(struct task_struct *tsk)
+{
+}
+
+static inline bool blk_needs_flush_plug(struct task_struct *tsk)
+{
+        return false;
+}
+
 #endif /* CONFIG_BLOCK */
 
 #endif
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
@@ -286,11 +286,6 @@ 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.
  */
 struct dm_table *dm_get_live_table(struct mapped_device *md);
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 39b68edb388..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;
@@ -101,17 +99,17 @@ 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 *);
 extern void elv_merge_requests(struct request_queue *, struct request *,
                                struct request *);
 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 e38b50a4b9d..b95199daa5e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -135,16 +135,10 @@ struct inodes_stat_t {
  *                      block layer could (in theory) choose to ignore this
  *                      request if it runs into resource problems.
  * WRITE                A normal async write. Device will be plugged.
- * WRITE_SYNC_PLUG      Synchronous write. Identical to WRITE, but passes down
+ * WRITE_SYNC           Synchronous write. Identical to WRITE, but passes down
  *                      the hint that someone will be waiting on this IO
- *                      shortly. The device must still be unplugged explicitly,
- *                      WRITE_SYNC_PLUG does not do this as we could be
- *                      submitting more writes before we actually wait on any
- *                      of them.
- * WRITE_SYNC           Like WRITE_SYNC_PLUG, but also unplugs the device
- *                      immediately after submission. The write equivalent
- *                      of READ_SYNC.
- * WRITE_ODIRECT_PLUG   Special case write for O_DIRECT only.
+ *                      shortly. The write equivalent of READ_SYNC.
+ * WRITE_ODIRECT        Special case write for O_DIRECT only.
  * WRITE_FLUSH          Like WRITE_SYNC but with preceding cache flush.
  * WRITE_FUA            Like WRITE_SYNC but data is guaranteed to be on
  *                      non-volatile media on completion.
@@ -160,18 +154,14 @@ struct inodes_stat_t {
 #define WRITE                   RW_MASK
 #define READA                   RWA_MASK
 
-#define READ_SYNC               (READ | REQ_SYNC | REQ_UNPLUG)
+#define READ_SYNC               (READ | REQ_SYNC)
 #define READ_META               (READ | REQ_META)
-#define WRITE_SYNC_PLUG         (WRITE | REQ_SYNC | REQ_NOIDLE)
-#define WRITE_SYNC              (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG)
-#define WRITE_ODIRECT_PLUG      (WRITE | REQ_SYNC)
+#define WRITE_SYNC              (WRITE | REQ_SYNC | REQ_NOIDLE)
+#define WRITE_ODIRECT           (WRITE | REQ_SYNC)
 #define WRITE_META              (WRITE | REQ_META)
-#define WRITE_FLUSH             (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
-                                 REQ_FLUSH)
-#define WRITE_FUA               (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
-                                 REQ_FUA)
-#define WRITE_FLUSH_FUA         (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
-                                 REQ_FLUSH | REQ_FUA)
+#define WRITE_FLUSH             (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH)
+#define WRITE_FUA               (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA)
+#define WRITE_FLUSH_FUA         (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA)
 
 #define SEL_IN          1
 #define SEL_OUT         2
@@ -583,7 +573,6 @@ 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);
@@ -342,17 +341,6 @@ static inline int lock_page_killable(struct page *page)
 }
 
 /*
- * 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/sched.h b/include/linux/sched.h
index 777d8a5ed06..96ac2264374 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -99,6 +99,7 @@ struct robust_list_head;
 struct bio_list;
 struct fs_struct;
 struct perf_event_context;
+struct blk_plug;
 
 /*
  * List of flags we want to share for kernel threads,
@@ -1429,6 +1430,11 @@ struct task_struct {
 /* stacked block device info */
         struct bio_list *bio_list;
 
+#ifdef CONFIG_BLOCK
+/* stack plugging */
+        struct blk_plug *plug;
+#endif
+
 /* VM state */
         struct reclaim_state *reclaim_state;
 
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/kernel/exit.c b/kernel/exit.c
index f9a45ebcc7b..6a488ad2dce 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -908,6 +908,7 @@ NORET_TYPE void do_exit(long code)
         profile_task_exit(tsk);
 
         WARN_ON(atomic_read(&tsk->fs_excl));
+        WARN_ON(blk_needs_flush_plug(tsk));
 
         if (unlikely(in_interrupt()))
                 panic("Aiee, killing interrupt handler!");
diff --git a/kernel/fork.c b/kernel/fork.c
index 25e429152dd..027c80e5162 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1204,6 +1204,9 @@ static struct task_struct *copy_process(unsigned long clone_flags,
          * Clear TID on mm_release()?
          */
         p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL;
+#ifdef CONFIG_BLOCK
+        p->plug = NULL;
+#endif
 #ifdef CONFIG_FUTEX
         p->robust_list = NULL;
 #ifdef CONFIG_COMPAT
diff --git a/kernel/power/block_io.c b/kernel/power/block_io.c
index 83bbc7c02df..d09dd10c5a5 100644
--- a/kernel/power/block_io.c
+++ b/kernel/power/block_io.c
@@ -28,7 +28,7 @@
 static int submit(int rw, struct block_device *bdev, sector_t sector,
                 struct page *page, struct bio **bio_chain)
 {
-        const int bio_rw = rw | REQ_SYNC | REQ_UNPLUG;
+        const int bio_rw = rw | REQ_SYNC;
         struct bio *bio;
 
         bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
diff --git a/kernel/sched.c b/kernel/sched.c
index 18d38e4ec7b..ca098bf4cc6 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3978,6 +3978,16 @@ need_resched_nonpreemptible:
                 switch_count = &prev->nvcsw;
         }
 
+        /*
+         * If we are going to sleep and we have plugged IO queued, make
+         * sure to submit it to avoid deadlocks.
+         */
+        if (prev->state != TASK_RUNNING && blk_needs_flush_plug(prev)) {
+                raw_spin_unlock(&rq->lock);
+                blk_flush_plug(prev);
+                raw_spin_lock(&rq->lock);
+        }
+
         pre_schedule(rq, prev);
 
         if (unlikely(!rq->nr_running))
@@ -5333,6 +5343,7 @@ void __sched io_schedule(void)
 
         delayacct_blkio_start();
         atomic_inc(&rq->nr_iowait);
+        blk_flush_plug(current);
         current->in_iowait = 1;
         schedule();
         current->in_iowait = 0;
@@ -5348,6 +5359,7 @@ long __sched io_schedule_timeout(long timeout)
 
         delayacct_blkio_start();
         atomic_inc(&rq->nr_iowait);
+        blk_flush_plug(current);
         current->in_iowait = 1;
         ret = schedule_timeout(timeout);
         current->in_iowait = 0;
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..f9a29c87a2c 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)
 {
@@ -1298,12 +1243,15 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
         unsigned long seg = 0;
         size_t count;
         loff_t *ppos = &iocb->ki_pos;
+        struct blk_plug plug;
 
         count = 0;
         retval = generic_segment_checks(iov, &nr_segs, &count, VERIFY_WRITE);
         if (retval)
                 return retval;
 
+        blk_start_plug(&plug);
+
         /* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
         if (filp->f_flags & O_DIRECT) {
                 loff_t size;
@@ -1376,6 +1324,7 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
                         break;
         }
 out:
+        blk_finish_plug(&plug);
         return retval;
 }
 EXPORT_SYMBOL(generic_file_aio_read);
@@ -2487,11 +2436,13 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 {
         struct file *file = iocb->ki_filp;
         struct inode *inode = file->f_mapping->host;
+        struct blk_plug plug;
         ssize_t ret;
 
         BUG_ON(iocb->ki_pos != pos);
 
         mutex_lock(&inode->i_mutex);
+        blk_start_plug(&plug);
         ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
         mutex_unlock(&inode->i_mutex);
 
@@ -2502,6 +2453,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
                 if (err < 0 && ret > 0)
                         ret = err;
         }
+        blk_finish_plug(&plug);
         return ret;
 }
 EXPORT_SYMBOL(generic_file_aio_write);
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/page_io.c b/mm/page_io.c
index 2dee975bf46..dc76b4d0611 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -106,7 +106,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
                 goto out;
         }
         if (wbc->sync_mode == WB_SYNC_ALL)
-                rw |= REQ_SYNC | REQ_UNPLUG;
+                rw |= REQ_SYNC;
         count_vm_event(PSWPOUT);
         set_page_writeback(page);
         unlock_page(page);
diff --git a/mm/readahead.c b/mm/readahead.c
index 77506a291a2..2c0cc489e28 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -109,9 +109,12 @@ EXPORT_SYMBOL(read_cache_pages);
 static int read_pages(struct address_space *mapping, struct file *filp,
                 struct list_head *pages, unsigned nr_pages)
 {
+        struct blk_plug plug;
         unsigned page_idx;
         int ret;
 
+        blk_start_plug(&plug);
+
         if (mapping->a_ops->readpages) {
                 ret = mapping->a_ops->readpages(filp, mapping, pages, nr_pages);
                 /* Clean up the remaining pages */
@@ -129,7 +132,10 @@ static int read_pages(struct address_space *mapping, struct file *filp,
                 page_cache_release(page);
         }
         ret = 0;
+
 out:
+        blk_finish_plug(&plug);
+
         return ret;
 }
 
@@ -554,17 +560,5 @@ 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 0341c5700e3..64d627ab624 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -95,39 +95,6 @@ __try_to_reclaim_swap(struct swap_info_struct *si, unsigned long offset)
 }
 
 /*
- * 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 6771ea70bfe..951cac21c2e 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);