Merge branch 'linus' into release

21 files changed, 583 insertions, 234 deletions

diff --git a/block/Kconfig b/block/Kconfig
index 1ab7c15c8d7a..0cbb3b88b59a 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -24,21 +24,23 @@ menuconfig BLOCK
 if BLOCK
 
 config LBD
-	bool "Support for Large Block Devices"
+	bool "Support for large block devices and files"
 	depends on !64BIT
 	help
-	  Enable block devices of size 2TB and larger.
+	  Enable block devices or files of size 2TB and larger.
 
 	  This option is required to support the full capacity of large
 	  (2TB+) block devices, including RAID, disk, Network Block Device,
 	  Logical Volume Manager (LVM) and loopback.
+	
+	  This option also enables support for single files larger than
+	  2TB.
 
-	  For example, RAID devices are frequently bigger than the capacity
-	  of the largest individual hard drive.
-
-	  This option is not required if you have individual disk drives
-	  which total 2TB+ and you are not aggregating the capacity into
-	  a large block device (e.g. using RAID or LVM).
+	  The ext4 filesystem requires that this feature be enabled in
+	  order to support filesystems that have the huge_file feature
+	  enabled.    Otherwise, it will refuse to mount any filesystems
+	  that use the huge_file feature, which is enabled by default
+	  by mke2fs.ext4.   The GFS2 filesystem also requires this feature.
 
 	  If unsure, say N.
 
@@ -47,6 +49,7 @@ config BLK_DEV_IO_TRACE
 	depends on SYSFS
 	select RELAY
 	select DEBUG_FS
+	select TRACEPOINTS
 	help
 	  Say Y here if you want to be able to trace the block layer actions
 	  on a given queue. Tracing allows you to see any traffic happening
@@ -57,15 +60,6 @@ config BLK_DEV_IO_TRACE
 
 	  If unsure, say N.
 
-config LSF
-	bool "Support for Large Single Files"
-	depends on !64BIT
-	help
-	  Say Y here if you want to be able to handle very large files (2TB
-	  and larger), otherwise say N.
-
-	  If unsure, say Y.
-
 config BLK_DEV_BSG
 	bool "Block layer SG support v4 (EXPERIMENTAL)"
 	depends on EXPERIMENTAL
diff --git a/block/as-iosched.c b/block/as-iosched.c
index 71f0abb219ee..631f6f44460a 100644
--- a/block/as-iosched.c
+++ b/block/as-iosched.c
@@ -1339,12 +1339,12 @@ static int as_may_queue(struct request_queue *q, int rw)
 	return ret;
 }
 
-static void as_exit_queue(elevator_t *e)
+static void as_exit_queue(struct elevator_queue *e)
 {
 	struct as_data *ad = e->elevator_data;
 
 	del_timer_sync(&ad->antic_timer);
-	kblockd_flush_work(&ad->antic_work);
+	cancel_work_sync(&ad->antic_work);
 
 	BUG_ON(!list_empty(&ad->fifo_list[REQ_SYNC]));
 	BUG_ON(!list_empty(&ad->fifo_list[REQ_ASYNC]));
@@ -1409,7 +1409,7 @@ as_var_store(unsigned long *var, const char *page, size_t count)
 	return count;
 }
 
-static ssize_t est_time_show(elevator_t *e, char *page)
+static ssize_t est_time_show(struct elevator_queue *e, char *page)
 {
 	struct as_data *ad = e->elevator_data;
 	int pos = 0;
@@ -1427,7 +1427,7 @@ static ssize_t est_time_show(elevator_t *e, char *page)
 }
 
 #define SHOW_FUNCTION(__FUNC, __VAR)				\
-static ssize_t __FUNC(elevator_t *e, char *page)		\
+static ssize_t __FUNC(struct elevator_queue *e, char *page)	\
 {								\
 	struct as_data *ad = e->elevator_data;			\
 	return as_var_show(jiffies_to_msecs((__VAR)), (page));	\
@@ -1440,7 +1440,7 @@ SHOW_FUNCTION(as_write_batch_expire_show, ad->batch_expire[REQ_ASYNC]);
 #undef SHOW_FUNCTION
 
 #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX)				\
-static ssize_t __FUNC(elevator_t *e, const char *page, size_t count)	\
+static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count)	\
 {									\
 	struct as_data *ad = e->elevator_data;				\
 	int ret = as_var_store(__PTR, (page), count);			\
diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 6e72d661ae42..8eba4e43bb0c 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -24,8 +24,8 @@
 int blk_queue_ordered(struct request_queue *q, unsigned ordered,
 		      prepare_flush_fn *prepare_flush_fn)
 {
-	if (ordered & (QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH) &&
-	    prepare_flush_fn == NULL) {
+	if (!prepare_flush_fn && (ordered & (QUEUE_ORDERED_DO_PREFLUSH |
+					     QUEUE_ORDERED_DO_POSTFLUSH))) {
 		printk(KERN_ERR "%s: prepare_flush_fn required\n", __func__);
 		return -EINVAL;
 	}
@@ -88,7 +88,7 @@ unsigned blk_ordered_req_seq(struct request *rq)
 		return QUEUE_ORDSEQ_DONE;
 }
 
-void blk_ordered_complete_seq(struct request_queue *q, unsigned seq, int error)
+bool blk_ordered_complete_seq(struct request_queue *q, unsigned seq, int error)
 {
 	struct request *rq;
 
@@ -99,7 +99,7 @@ void blk_ordered_complete_seq(struct request_queue *q, unsigned seq, int error)
 	q->ordseq |= seq;
 
 	if (blk_ordered_cur_seq(q) != QUEUE_ORDSEQ_DONE)
-		return;
+		return false;
 
 	/*
 	 * Okay, sequence complete.
@@ -109,6 +109,8 @@ void blk_ordered_complete_seq(struct request_queue *q, unsigned seq, int error)
 
 	if (__blk_end_request(rq, q->orderr, blk_rq_bytes(rq)))
 		BUG();
+
+	return true;
 }
 
 static void pre_flush_end_io(struct request *rq, int error)
@@ -134,7 +136,7 @@ static void queue_flush(struct request_queue *q, unsigned which)
 	struct request *rq;
 	rq_end_io_fn *end_io;
 
-	if (which == QUEUE_ORDERED_PREFLUSH) {
+	if (which == QUEUE_ORDERED_DO_PREFLUSH) {
 		rq = &q->pre_flush_rq;
 		end_io = pre_flush_end_io;
 	} else {
@@ -151,80 +153,110 @@ static void queue_flush(struct request_queue *q, unsigned which)
 	elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
 }
 
-static inline struct request *start_ordered(struct request_queue *q,
-					    struct request *rq)
+static inline bool start_ordered(struct request_queue *q, struct request **rqp)
 {
+	struct request *rq = *rqp;
+	unsigned skip = 0;
+
 	q->orderr = 0;
 	q->ordered = q->next_ordered;
 	q->ordseq |= QUEUE_ORDSEQ_STARTED;
 
 	/*
-	 * Prep proxy barrier request.
+	 * For an empty barrier, there's no actual BAR request, which
+	 * in turn makes POSTFLUSH unnecessary.  Mask them off.
 	 */
+	if (!rq->hard_nr_sectors) {
+		q->ordered &= ~(QUEUE_ORDERED_DO_BAR |
+				QUEUE_ORDERED_DO_POSTFLUSH);
+		/*
+		 * Empty barrier on a write-through device w/ ordered
+		 * tag has no command to issue and without any command
+		 * to issue, ordering by tag can't be used.  Drain
+		 * instead.
+		 */
+		if ((q->ordered & QUEUE_ORDERED_BY_TAG) &&
+		    !(q->ordered & QUEUE_ORDERED_DO_PREFLUSH)) {
+			q->ordered &= ~QUEUE_ORDERED_BY_TAG;
+			q->ordered |= QUEUE_ORDERED_BY_DRAIN;
+		}
+	}
+
+	/* stash away the original request */
 	elv_dequeue_request(q, rq);
 	q->orig_bar_rq = rq;
-	rq = &q->bar_rq;
-	blk_rq_init(q, rq);
-	if (bio_data_dir(q->orig_bar_rq->bio) == WRITE)
-		rq->cmd_flags |= REQ_RW;
-	if (q->ordered & QUEUE_ORDERED_FUA)
-		rq->cmd_flags |= REQ_FUA;
-	init_request_from_bio(rq, q->orig_bar_rq->bio);
-	rq->end_io = bar_end_io;
+	rq = NULL;
 
 	/*
 	 * Queue ordered sequence.  As we stack them at the head, we
 	 * need to queue in reverse order.  Note that we rely on that
 	 * no fs request uses ELEVATOR_INSERT_FRONT and thus no fs
-	 * request gets inbetween ordered sequence. If this request is
-	 * an empty barrier, we don't need to do a postflush ever since
-	 * there will be no data written between the pre and post flush.
-	 * Hence a single flush will suffice.
+	 * request gets inbetween ordered sequence.
 	 */
-	if ((q->ordered & QUEUE_ORDERED_POSTFLUSH) && !blk_empty_barrier(rq))
-		queue_flush(q, QUEUE_ORDERED_POSTFLUSH);
-	else
-		q->ordseq |= QUEUE_ORDSEQ_POSTFLUSH;
+	if (q->ordered & QUEUE_ORDERED_DO_POSTFLUSH) {
+		queue_flush(q, QUEUE_ORDERED_DO_POSTFLUSH);
+		rq = &q->post_flush_rq;
+	} else
+		skip |= QUEUE_ORDSEQ_POSTFLUSH;
 
-	elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
+	if (q->ordered & QUEUE_ORDERED_DO_BAR) {
+		rq = &q->bar_rq;
+
+		/* initialize proxy request and queue it */
+		blk_rq_init(q, rq);
+		if (bio_data_dir(q->orig_bar_rq->bio) == WRITE)
+			rq->cmd_flags |= REQ_RW;
+		if (q->ordered & QUEUE_ORDERED_DO_FUA)
+			rq->cmd_flags |= REQ_FUA;
+		init_request_from_bio(rq, q->orig_bar_rq->bio);
+		rq->end_io = bar_end_io;
 
-	if (q->ordered & QUEUE_ORDERED_PREFLUSH) {
-		queue_flush(q, QUEUE_ORDERED_PREFLUSH);
+		elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
+	} else
+		skip |= QUEUE_ORDSEQ_BAR;
+
+	if (q->ordered & QUEUE_ORDERED_DO_PREFLUSH) {
+		queue_flush(q, QUEUE_ORDERED_DO_PREFLUSH);
 		rq = &q->pre_flush_rq;
 	} else
-		q->ordseq |= QUEUE_ORDSEQ_PREFLUSH;
+		skip |= QUEUE_ORDSEQ_PREFLUSH;
 
-	if ((q->ordered & QUEUE_ORDERED_TAG) || q->in_flight == 0)
-		q->ordseq |= QUEUE_ORDSEQ_DRAIN;
-	else
+	if ((q->ordered & QUEUE_ORDERED_BY_DRAIN) && q->in_flight)
 		rq = NULL;
+	else
+		skip |= QUEUE_ORDSEQ_DRAIN;
+
+	*rqp = rq;
 
-	return rq;
+	/*
+	 * Complete skipped sequences.  If whole sequence is complete,
+	 * return false to tell elevator that this request is gone.
+	 */
+	return !blk_ordered_complete_seq(q, skip, 0);
 }
 
-int blk_do_ordered(struct request_queue *q, struct request **rqp)
+bool blk_do_ordered(struct request_queue *q, struct request **rqp)
 {
 	struct request *rq = *rqp;
 	const int is_barrier = blk_fs_request(rq) && blk_barrier_rq(rq);
 
 	if (!q->ordseq) {
 		if (!is_barrier)
-			return 1;
+			return true;
 
-		if (q->next_ordered != QUEUE_ORDERED_NONE) {
-			*rqp = start_ordered(q, rq);
-			return 1;
-		} else {
+		if (q->next_ordered != QUEUE_ORDERED_NONE)
+			return start_ordered(q, rqp);
+		else {
 			/*
-			 * This can happen when the queue switches to
-			 * ORDERED_NONE while this request is on it.
+			 * Queue ordering not supported.  Terminate
+			 * with prejudice.
 			 */
 			elv_dequeue_request(q, rq);
 			if (__blk_end_request(rq, -EOPNOTSUPP,
 					      blk_rq_bytes(rq)))
 				BUG();
 			*rqp = NULL;
-			return 0;
+			return false;
 		}
 	}
 
@@ -235,9 +267,9 @@ int blk_do_ordered(struct request_queue *q, struct request **rqp)
 	/* Special requests are not subject to ordering rules. */
 	if (!blk_fs_request(rq) &&
 	    rq != &q->pre_flush_rq && rq != &q->post_flush_rq)
-		return 1;
+		return true;
 
-	if (q->ordered & QUEUE_ORDERED_TAG) {
+	if (q->ordered & QUEUE_ORDERED_BY_TAG) {
 		/* Ordered by tag.  Blocking the next barrier is enough. */
 		if (is_barrier && rq != &q->bar_rq)
 			*rqp = NULL;
@@ -248,7 +280,7 @@ int blk_do_ordered(struct request_queue *q, struct request **rqp)
 			*rqp = NULL;
 	}
 
-	return 1;
+	return true;
 }
 
 static void bio_end_empty_barrier(struct bio *bio, int err)
diff --git a/block/blk-core.c b/block/blk-core.c
index c36aa98fafa3..a824e49c0d0a 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -28,9 +28,23 @@
 #include <linux/task_io_accounting_ops.h>
 #include <linux/blktrace_api.h>
 #include <linux/fault-inject.h>
+#include <trace/block.h>
 
 #include "blk.h"
 
+DEFINE_TRACE(block_plug);
+DEFINE_TRACE(block_unplug_io);
+DEFINE_TRACE(block_unplug_timer);
+DEFINE_TRACE(block_getrq);
+DEFINE_TRACE(block_sleeprq);
+DEFINE_TRACE(block_rq_requeue);
+DEFINE_TRACE(block_bio_backmerge);
+DEFINE_TRACE(block_bio_frontmerge);
+DEFINE_TRACE(block_bio_queue);
+DEFINE_TRACE(block_rq_complete);
+DEFINE_TRACE(block_remap);	/* Also used in drivers/md/dm.c */
+EXPORT_TRACEPOINT_SYMBOL_GPL(block_remap);
+
 static int __make_request(struct request_queue *q, struct bio *bio);
 
 /*
@@ -139,6 +153,9 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
 			nbytes = bio->bi_size;
 		}
 
+		if (unlikely(rq->cmd_flags & REQ_QUIET))
+			set_bit(BIO_QUIET, &bio->bi_flags);
+
 		bio->bi_size -= nbytes;
 		bio->bi_sector += (nbytes >> 9);
 
@@ -205,7 +222,7 @@ void blk_plug_device(struct request_queue *q)
 
 	if (!queue_flag_test_and_set(QUEUE_FLAG_PLUGGED, q)) {
 		mod_timer(&q->unplug_timer, jiffies + q->unplug_delay);
-		blk_add_trace_generic(q, NULL, 0, BLK_TA_PLUG);
+		trace_block_plug(q);
 	}
 }
 EXPORT_SYMBOL(blk_plug_device);
@@ -251,8 +268,7 @@ void __generic_unplug_device(struct request_queue *q)
 {
 	if (unlikely(blk_queue_stopped(q)))
 		return;
-
-	if (!blk_remove_plug(q))
+	if (!blk_remove_plug(q) && !blk_queue_nonrot(q))
 		return;
 
 	q->request_fn(q);
@@ -292,9 +308,7 @@ void blk_unplug_work(struct work_struct *work)
 	struct request_queue *q =
 		container_of(work, struct request_queue, unplug_work);
 
-	blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
-				q->rq.count[READ] + q->rq.count[WRITE]);
-
+	trace_block_unplug_io(q);
 	q->unplug_fn(q);
 }
 
@@ -302,9 +316,7 @@ void blk_unplug_timeout(unsigned long data)
 {
 	struct request_queue *q = (struct request_queue *)data;
 
-	blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_TIMER, NULL,
-				q->rq.count[READ] + q->rq.count[WRITE]);
-
+	trace_block_unplug_timer(q);
 	kblockd_schedule_work(q, &q->unplug_work);
 }
 
@@ -314,9 +326,7 @@ void blk_unplug(struct request_queue *q)
 	 * devices don't necessarily have an ->unplug_fn defined
 	 */
 	if (q->unplug_fn) {
-		blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
-					q->rq.count[READ] + q->rq.count[WRITE]);
-
+		trace_block_unplug_io(q);
 		q->unplug_fn(q);
 	}
 }
@@ -396,7 +406,8 @@ EXPORT_SYMBOL(blk_stop_queue);
 void blk_sync_queue(struct request_queue *q)
 {
 	del_timer_sync(&q->unplug_timer);
-	kblockd_flush_work(&q->unplug_work);
+	del_timer_sync(&q->timeout);
+	cancel_work_sync(&q->unplug_work);
 }
 EXPORT_SYMBOL(blk_sync_queue);
 
@@ -822,7 +833,7 @@ rq_starved:
 	if (ioc_batching(q, ioc))
 		ioc->nr_batch_requests--;
 
-	blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ);
+	trace_block_getrq(q, bio, rw);
 out:
 	return rq;
 }
@@ -848,7 +859,7 @@ static struct request *get_request_wait(struct request_queue *q, int rw_flags,
 		prepare_to_wait_exclusive(&rl->wait[rw], &wait,
 				TASK_UNINTERRUPTIBLE);
 
-		blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ);
+		trace_block_sleeprq(q, bio, rw);
 
 		__generic_unplug_device(q);
 		spin_unlock_irq(q->queue_lock);
@@ -928,7 +939,7 @@ void blk_requeue_request(struct request_queue *q, struct request *rq)
 {
 	blk_delete_timer(rq);
 	blk_clear_rq_complete(rq);
-	blk_add_trace_rq(q, rq, BLK_TA_REQUEUE);
+	trace_block_rq_requeue(q, rq);
 
 	if (blk_rq_tagged(rq))
 		blk_queue_end_tag(q, rq);
@@ -1127,7 +1138,7 @@ void init_request_from_bio(struct request *req, struct bio *bio)
 static int __make_request(struct request_queue *q, struct bio *bio)
 {
 	struct request *req;
-	int el_ret, nr_sectors, barrier, discard, err;
+	int el_ret, nr_sectors;
 	const unsigned short prio = bio_prio(bio);
 	const int sync = bio_sync(bio);
 	int rw_flags;
@@ -1141,22 +1152,9 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 	 */
 	blk_queue_bounce(q, &bio);
 
-	barrier = bio_barrier(bio);
-	if (unlikely(barrier) && bio_has_data(bio) &&
-	    (q->next_ordered == QUEUE_ORDERED_NONE)) {
-		err = -EOPNOTSUPP;
-		goto end_io;
-	}
-
-	discard = bio_discard(bio);
-	if (unlikely(discard) && !q->prepare_discard_fn) {
-		err = -EOPNOTSUPP;
-		goto end_io;
-	}
-
 	spin_lock_irq(q->queue_lock);
 
-	if (unlikely(barrier) || elv_queue_empty(q))
+	if (unlikely(bio_barrier(bio)) || elv_queue_empty(q))
 		goto get_rq;
 
 	el_ret = elv_merge(q, &req, bio);
@@ -1167,7 +1165,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 		if (!ll_back_merge_fn(q, req, bio))
 			break;
 
-		blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
+		trace_block_bio_backmerge(q, bio);
 
 		req->biotail->bi_next = bio;
 		req->biotail = bio;
@@ -1186,7 +1184,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 		if (!ll_front_merge_fn(q, req, bio))
 			break;
 
-		blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
+		trace_block_bio_frontmerge(q, bio);
 
 		bio->bi_next = req->bio;
 		req->bio = bio;
@@ -1242,18 +1240,14 @@ get_rq:
 	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 (elv_queue_empty(q))
+	if (!blk_queue_nonrot(q) && elv_queue_empty(q))
 		blk_plug_device(q);
 	add_request(q, req);
 out:
-	if (sync)
+	if (sync || blk_queue_nonrot(q))
 		__generic_unplug_device(q);
 	spin_unlock_irq(q->queue_lock);
 	return 0;
-
-end_io:
-	bio_endio(bio, err);
-	return 0;
 }
 
 /*
@@ -1269,7 +1263,7 @@ static inline void blk_partition_remap(struct bio *bio)
 		bio->bi_sector += p->start_sect;
 		bio->bi_bdev = bdev->bd_contains;
 
-		blk_add_trace_remap(bdev_get_queue(bio->bi_bdev), bio,
+		trace_block_remap(bdev_get_queue(bio->bi_bdev), bio,
 				    bdev->bd_dev, bio->bi_sector,
 				    bio->bi_sector - p->start_sect);
 	}
@@ -1406,15 +1400,13 @@ static inline void __generic_make_request(struct bio *bio)
 		char b[BDEVNAME_SIZE];
 
 		q = bdev_get_queue(bio->bi_bdev);
-		if (!q) {
+		if (unlikely(!q)) {
 			printk(KERN_ERR
 			       "generic_make_request: Trying to access "
 				"nonexistent block-device %s (%Lu)\n",
 				bdevname(bio->bi_bdev, b),
 				(long long) bio->bi_sector);
-end_io:
-			bio_endio(bio, err);
-			break;
+			goto end_io;
 		}
 
 		if (unlikely(nr_sectors > q->max_hw_sectors)) {
@@ -1441,24 +1433,29 @@ end_io:
 			goto end_io;
 
 		if (old_sector != -1)
-			blk_add_trace_remap(q, bio, old_dev, bio->bi_sector,
+			trace_block_remap(q, bio, old_dev, bio->bi_sector,
 					    old_sector);
 
-		blk_add_trace_bio(q, bio, BLK_TA_QUEUE);
+		trace_block_bio_queue(q, bio);
 
 		old_sector = bio->bi_sector;
 		old_dev = bio->bi_bdev->bd_dev;
 
 		if (bio_check_eod(bio, nr_sectors))
 			goto end_io;
-		if ((bio_empty_barrier(bio) && !q->prepare_flush_fn) ||
-		    (bio_discard(bio) && !q->prepare_discard_fn)) {
+
+		if (bio_discard(bio) && !q->prepare_discard_fn) {
 			err = -EOPNOTSUPP;
 			goto end_io;
 		}
 
 		ret = q->make_request_fn(q, bio);
 	} while (ret);
+
+	return;
+
+end_io:
+	bio_endio(bio, err);
 }
 
 /*
@@ -1678,7 +1675,7 @@ static int __end_that_request_first(struct request *req, int error,
 	int total_bytes, bio_nbytes, next_idx = 0;
 	struct bio *bio;
 
-	blk_add_trace_rq(req->q, req, BLK_TA_COMPLETE);
+	trace_block_rq_complete(req->q, req);
 
 	/*
 	 * for a REQ_TYPE_BLOCK_PC request, we want to carry any eventual
@@ -1708,14 +1705,6 @@ static int __end_that_request_first(struct request *req, int error,
 	while ((bio = req->bio) != NULL) {
 		int nbytes;
 
-		/*
-		 * For an empty barrier request, the low level driver must
-		 * store a potential error location in ->sector. We pass
-		 * that back up in ->bi_sector.
-		 */
-		if (blk_empty_barrier(req))
-			bio->bi_sector = req->sector;
-
 		if (nr_bytes >= bio->bi_size) {
 			req->bio = bio->bi_next;
 			nbytes = bio->bi_size;
@@ -2135,12 +2124,6 @@ int kblockd_schedule_work(struct request_queue *q, struct work_struct *work)
 }
 EXPORT_SYMBOL(kblockd_schedule_work);
 
-void kblockd_flush_work(struct work_struct *work)
-{
-	cancel_work_sync(work);
-}
-EXPORT_SYMBOL(kblockd_flush_work);
-
 int __init blk_dev_init(void)
 {
 	kblockd_workqueue = create_workqueue("kblockd");
diff --git a/block/blk-map.c b/block/blk-map.c
index 2990447f45e9..f103729b462f 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -42,7 +42,7 @@ static int __blk_rq_unmap_user(struct bio *bio)
 
 static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
 			     struct rq_map_data *map_data, void __user *ubuf,
-			     unsigned int len, int null_mapped, gfp_t gfp_mask)
+			     unsigned int len, gfp_t gfp_mask)
 {
 	unsigned long uaddr;
 	struct bio *bio, *orig_bio;
@@ -63,7 +63,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
 	if (IS_ERR(bio))
 		return PTR_ERR(bio);
 
-	if (null_mapped)
+	if (map_data && map_data->null_mapped)
 		bio->bi_flags |= (1 << BIO_NULL_MAPPED);
 
 	orig_bio = bio;
@@ -114,17 +114,15 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
 {
 	unsigned long bytes_read = 0;
 	struct bio *bio = NULL;
-	int ret, null_mapped = 0;
+	int ret;
 
 	if (len > (q->max_hw_sectors << 9))
 		return -EINVAL;
 	if (!len)
 		return -EINVAL;
-	if (!ubuf) {
-		if (!map_data || rq_data_dir(rq) != READ)
-			return -EINVAL;
-		null_mapped = 1;
-	}
+
+	if (!ubuf && (!map_data || !map_data->null_mapped))
+		return -EINVAL;
 
 	while (bytes_read != len) {
 		unsigned long map_len, end, start;
@@ -143,13 +141,16 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
 			map_len -= PAGE_SIZE;
 
 		ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len,
-					null_mapped, gfp_mask);
+					gfp_mask);
 		if (ret < 0)
 			goto unmap_rq;
 		if (!bio)
 			bio = rq->bio;
 		bytes_read += ret;
 		ubuf += ret;
+
+		if (map_data)
+			map_data->offset += ret;
 	}
 
 	if (!bio_flagged(bio, BIO_USER_MAPPED))
diff --git a/block/blk-settings.c b/block/blk-settings.c
index afa55e14e278..59fd05d9f1d5 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -319,9 +319,9 @@ void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b)
 	t->max_hw_sectors = min_not_zero(t->max_hw_sectors, b->max_hw_sectors);
 	t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask, b->seg_boundary_mask);
 
-	t->max_phys_segments = min(t->max_phys_segments, b->max_phys_segments);
-	t->max_hw_segments = min(t->max_hw_segments, b->max_hw_segments);
-	t->max_segment_size = min(t->max_segment_size, b->max_segment_size);
+	t->max_phys_segments = min_not_zero(t->max_phys_segments, b->max_phys_segments);
+	t->max_hw_segments = min_not_zero(t->max_hw_segments, b->max_hw_segments);
+	t->max_segment_size = min_not_zero(t->max_segment_size, b->max_segment_size);
 	t->hardsect_size = max(t->hardsect_size, b->hardsect_size);
 	if (!t->queue_lock)
 		WARN_ON_ONCE(1);
diff --git a/block/blk-softirq.c b/block/blk-softirq.c
index e660d26ca656..ce0efc6b26dc 100644
--- a/block/blk-softirq.c
+++ b/block/blk-softirq.c
@@ -161,7 +161,7 @@ void blk_complete_request(struct request *req)
 }
 EXPORT_SYMBOL(blk_complete_request);
 
-__init int blk_softirq_init(void)
+static __init int blk_softirq_init(void)
 {
 	int i;
 
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 21e275d7eed9..a29cb788e408 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -88,9 +88,7 @@ queue_ra_store(struct request_queue *q, const char *page, size_t count)
 	unsigned long ra_kb;
 	ssize_t ret = queue_var_store(&ra_kb, page, count);
 
-	spin_lock_irq(q->queue_lock);
 	q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
-	spin_unlock_irq(q->queue_lock);
 
 	return ret;
 }
@@ -117,10 +115,7 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
 
 	if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
 		return -EINVAL;
-	/*
-	 * Take the queue lock to update the readahead and max_sectors
-	 * values synchronously:
-	 */
+
 	spin_lock_irq(q->queue_lock);
 	q->max_sectors = max_sectors_kb << 1;
 	spin_unlock_irq(q->queue_lock);
diff --git a/block/blk-tag.c b/block/blk-tag.c
index c0d419e84ce7..3c518e3303ae 100644
--- a/block/blk-tag.c
+++ b/block/blk-tag.c
@@ -158,7 +158,6 @@ fail:
 /**
  * blk_init_tags - initialize the tag info for an external tag map
  * @depth:	the maximum queue depth supported
- * @tags: the tag to use
  **/
 struct blk_queue_tag *blk_init_tags(int depth)
 {
diff --git a/block/blk-timeout.c b/block/blk-timeout.c
index 69185ea9fae2..a09535377a94 100644
--- a/block/blk-timeout.c
+++ b/block/blk-timeout.c
@@ -73,11 +73,7 @@ ssize_t part_timeout_store(struct device *dev, struct device_attribute *attr,
  */
 void blk_delete_timer(struct request *req)
 {
-	struct request_queue *q = req->q;
-
 	list_del_init(&req->timeout_list);
-	if (list_empty(&q->timeout_list))
-		del_timer(&q->timeout);
 }
 
 static void blk_rq_timed_out(struct request *req)
@@ -111,7 +107,7 @@ static void blk_rq_timed_out(struct request *req)
 void blk_rq_timed_out_timer(unsigned long data)
 {
 	struct request_queue *q = (struct request_queue *) data;
-	unsigned long flags, uninitialized_var(next), next_set = 0;
+	unsigned long flags, next = 0;
 	struct request *rq, *tmp;
 
 	spin_lock_irqsave(q->queue_lock, flags);
@@ -126,15 +122,18 @@ void blk_rq_timed_out_timer(unsigned long data)
 			if (blk_mark_rq_complete(rq))
 				continue;
 			blk_rq_timed_out(rq);
+		} else {
+			if (!next || time_after(next, rq->deadline))
+				next = rq->deadline;
 		}
-		if (!next_set) {
-			next = rq->deadline;
-			next_set = 1;
-		} else if (time_after(next, rq->deadline))
-			next = rq->deadline;
 	}
 
-	if (next_set && !list_empty(&q->timeout_list))
+	/*
+	 * next can never be 0 here with the list non-empty, since we always
+	 * bump ->deadline to 1 so we can detect if the timer was ever added
+	 * or not. See comment in blk_add_timer()
+	 */
+	if (next)
 		mod_timer(&q->timeout, round_jiffies_up(next));
 
 	spin_unlock_irqrestore(q->queue_lock, flags);
diff --git a/block/blk.h b/block/blk.h
index d2e49af90db5..6e1ed40534e9 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -99,8 +99,8 @@ static inline int queue_congestion_off_threshold(struct request_queue *q)
 static inline int blk_cpu_to_group(int cpu)
 {
 #ifdef CONFIG_SCHED_MC
-	cpumask_t mask = cpu_coregroup_map(cpu);
-	return first_cpu(mask);
+	const struct cpumask *mask = cpu_coregroup_mask(cpu);
+	return cpumask_first(mask);
 #elif defined(CONFIG_SCHED_SMT)
 	return first_cpu(per_cpu(cpu_sibling_map, cpu));
 #else
diff --git a/block/blktrace.c b/block/blktrace.c
index 85049a7e7a17..b0a2cae886db 100644
--- a/block/blktrace.c
+++ b/block/blktrace.c
@@ -23,10 +23,18 @@
 #include <linux/mutex.h>
 #include <linux/debugfs.h>
 #include <linux/time.h>
+#include <trace/block.h>
 #include <asm/uaccess.h>
 
 static unsigned int blktrace_seq __read_mostly = 1;
 
+/* Global reference count of probes */
+static DEFINE_MUTEX(blk_probe_mutex);
+static atomic_t blk_probes_ref = ATOMIC_INIT(0);
+
+static int blk_register_tracepoints(void);
+static void blk_unregister_tracepoints(void);
+
 /*
  * Send out a notify message.
  */
@@ -119,7 +127,7 @@ static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK
  * The worker for the various blk_add_trace*() types. Fills out a
  * blk_io_trace structure and places it in a per-cpu subbuffer.
  */
-void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
+static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
 		     int rw, u32 what, int error, int pdu_len, void *pdu_data)
 {
 	struct task_struct *tsk = current;
@@ -177,8 +185,6 @@ void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
 	local_irq_restore(flags);
 }
 
-EXPORT_SYMBOL_GPL(__blk_add_trace);
-
 static struct dentry *blk_tree_root;
 static DEFINE_MUTEX(blk_tree_mutex);
 static unsigned int root_users;
@@ -237,6 +243,10 @@ static void blk_trace_cleanup(struct blk_trace *bt)
 	free_percpu(bt->sequence);
 	free_percpu(bt->msg_data);
 	kfree(bt);
+	mutex_lock(&blk_probe_mutex);
+	if (atomic_dec_and_test(&blk_probes_ref))
+		blk_unregister_tracepoints();
+	mutex_unlock(&blk_probe_mutex);
 }
 
 int blk_trace_remove(struct request_queue *q)
@@ -428,6 +438,14 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 	bt->pid = buts->pid;
 	bt->trace_state = Blktrace_setup;
 
+	mutex_lock(&blk_probe_mutex);
+	if (atomic_add_return(1, &blk_probes_ref) == 1) {
+		ret = blk_register_tracepoints();
+		if (ret)
+			goto probe_err;
+	}
+	mutex_unlock(&blk_probe_mutex);
+
 	ret = -EBUSY;
 	old_bt = xchg(&q->blk_trace, bt);
 	if (old_bt) {
@@ -436,6 +454,9 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 	}
 
 	return 0;
+probe_err:
+	atomic_dec(&blk_probes_ref);
+	mutex_unlock(&blk_probe_mutex);
 err:
 	if (dir)
 		blk_remove_tree(dir);
@@ -562,3 +583,308 @@ void blk_trace_shutdown(struct request_queue *q)
 		blk_trace_remove(q);
 	}
 }
+
+/*
+ * blktrace probes
+ */
+
+/**
+ * blk_add_trace_rq - Add a trace for a request oriented action
+ * @q:		queue the io is for
+ * @rq:		the source request
+ * @what:	the action
+ *
+ * Description:
+ *     Records an action against a request. Will log the bio offset + size.
+ *
+ **/
+static void blk_add_trace_rq(struct request_queue *q, struct request *rq,
+				    u32 what)
+{
+	struct blk_trace *bt = q->blk_trace;
+	int rw = rq->cmd_flags & 0x03;
+
+	if (likely(!bt))
+		return;
+
+	if (blk_discard_rq(rq))
+		rw |= (1 << BIO_RW_DISCARD);
+
+	if (blk_pc_request(rq)) {
+		what |= BLK_TC_ACT(BLK_TC_PC);
+		__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors,
+				sizeof(rq->cmd), rq->cmd);
+	} else  {
+		what |= BLK_TC_ACT(BLK_TC_FS);
+		__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9,
+				rw, what, rq->errors, 0, NULL);
+	}
+}
+
+static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq)
+{
+	blk_add_trace_rq(q, rq, BLK_TA_ABORT);
+}
+
+static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq)
+{
+	blk_add_trace_rq(q, rq, BLK_TA_INSERT);
+}
+
+static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq)
+{
+	blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
+}
+
+static void blk_add_trace_rq_requeue(struct request_queue *q, struct request *rq)
+{
+	blk_add_trace_rq(q, rq, BLK_TA_REQUEUE);
+}
+
+static void blk_add_trace_rq_complete(struct request_queue *q, struct request *rq)
+{
+	blk_add_trace_rq(q, rq, BLK_TA_COMPLETE);
+}
+
+/**
+ * blk_add_trace_bio - Add a trace for a bio oriented action
+ * @q:		queue the io is for
+ * @bio:	the source bio
+ * @what:	the action
+ *
+ * Description:
+ *     Records an action against a bio. Will log the bio offset + size.
+ *
+ **/
+static void blk_add_trace_bio(struct request_queue *q, struct bio *bio,
+				     u32 what)
+{
+	struct blk_trace *bt = q->blk_trace;
+
+	if (likely(!bt))
+		return;
+
+	__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what,
+			!bio_flagged(bio, BIO_UPTODATE), 0, NULL);
+}
+
+static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio)
+{
+	blk_add_trace_bio(q, bio, BLK_TA_BOUNCE);
+}
+
+static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio)
+{
+	blk_add_trace_bio(q, bio, BLK_TA_COMPLETE);
+}
+
+static void blk_add_trace_bio_backmerge(struct request_queue *q, struct bio *bio)
+{
+	blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
+}
+
+static void blk_add_trace_bio_frontmerge(struct request_queue *q, struct bio *bio)
+{
+	blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
+}
+
+static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio)
+{
+	blk_add_trace_bio(q, bio, BLK_TA_QUEUE);
+}
+
+static void blk_add_trace_getrq(struct request_queue *q, struct bio *bio, int rw)
+{
+	if (bio)
+		blk_add_trace_bio(q, bio, BLK_TA_GETRQ);
+	else {
+		struct blk_trace *bt = q->blk_trace;
+
+		if (bt)
+			__blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL);
+	}
+}
+
+
+static void blk_add_trace_sleeprq(struct request_queue *q, struct bio *bio, int rw)
+{
+	if (bio)
+		blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ);
+	else {
+		struct blk_trace *bt = q->blk_trace;
+
+		if (bt)
+			__blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, 0, 0, NULL);
+	}
+}
+
+static void blk_add_trace_plug(struct request_queue *q)
+{
+	struct blk_trace *bt = q->blk_trace;
+
+	if (bt)
+		__blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL);
+}
+
+static void blk_add_trace_unplug_io(struct request_queue *q)
+{
+	struct blk_trace *bt = q->blk_trace;
+
+	if (bt) {
+		unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE];
+		__be64 rpdu = cpu_to_be64(pdu);
+
+		__blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0,
+				sizeof(rpdu), &rpdu);
+	}
+}
+
+static void blk_add_trace_unplug_timer(struct request_queue *q)
+{
+	struct blk_trace *bt = q->blk_trace;
+
+	if (bt) {
+		unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE];
+		__be64 rpdu = cpu_to_be64(pdu);
+
+		__blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0,
+				sizeof(rpdu), &rpdu);
+	}
+}
+
+static void blk_add_trace_split(struct request_queue *q, struct bio *bio,
+				unsigned int pdu)
+{
+	struct blk_trace *bt = q->blk_trace;
+
+	if (bt) {
+		__be64 rpdu = cpu_to_be64(pdu);
+
+		__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw,
+				BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE),
+				sizeof(rpdu), &rpdu);
+	}
+}
+
+/**
+ * blk_add_trace_remap - Add a trace for a remap operation
+ * @q:		queue the io is for
+ * @bio:	the source bio
+ * @dev:	target device
+ * @from:	source sector
+ * @to:		target sector
+ *
+ * Description:
+ *     Device mapper or raid target sometimes need to split a bio because
+ *     it spans a stripe (or similar). Add a trace for that action.
+ *
+ **/
+static void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
+				       dev_t dev, sector_t from, sector_t to)
+{
+	struct blk_trace *bt = q->blk_trace;
+	struct blk_io_trace_remap r;
+
+	if (likely(!bt))
+		return;
+
+	r.device = cpu_to_be32(dev);
+	r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev);
+	r.sector = cpu_to_be64(to);
+
+	__blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP,
+			!bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
+}
+
+/**
+ * blk_add_driver_data - Add binary message with driver-specific data
+ * @q:		queue the io is for
+ * @rq:		io request
+ * @data:	driver-specific data
+ * @len:	length of driver-specific data
+ *
+ * Description:
+ *     Some drivers might want to write driver-specific data per request.
+ *
+ **/
+void blk_add_driver_data(struct request_queue *q,
+			 struct request *rq,
+			 void *data, size_t len)
+{
+	struct blk_trace *bt = q->blk_trace;
+
+	if (likely(!bt))
+		return;
+
+	if (blk_pc_request(rq))
+		__blk_add_trace(bt, 0, rq->data_len, 0, BLK_TA_DRV_DATA,
+				rq->errors, len, data);
+	else
+		__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9,
+				0, BLK_TA_DRV_DATA, rq->errors, len, data);
+}
+EXPORT_SYMBOL_GPL(blk_add_driver_data);
+
+static int blk_register_tracepoints(void)
+{
+	int ret;
+
+	ret = register_trace_block_rq_abort(blk_add_trace_rq_abort);
+	WARN_ON(ret);
+	ret = register_trace_block_rq_insert(blk_add_trace_rq_insert);
+	WARN_ON(ret);
+	ret = register_trace_block_rq_issue(blk_add_trace_rq_issue);
+	WARN_ON(ret);
+	ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue);
+	WARN_ON(ret);
+	ret = register_trace_block_rq_complete(blk_add_trace_rq_complete);
+	WARN_ON(ret);
+	ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce);
+	WARN_ON(ret);
+	ret = register_trace_block_bio_complete(blk_add_trace_bio_complete);
+	WARN_ON(ret);
+	ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge);
+	WARN_ON(ret);
+	ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge);
+	WARN_ON(ret);
+	ret = register_trace_block_bio_queue(blk_add_trace_bio_queue);
+	WARN_ON(ret);
+	ret = register_trace_block_getrq(blk_add_trace_getrq);
+	WARN_ON(ret);
+	ret = register_trace_block_sleeprq(blk_add_trace_sleeprq);
+	WARN_ON(ret);
+	ret = register_trace_block_plug(blk_add_trace_plug);
+	WARN_ON(ret);
+	ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer);
+	WARN_ON(ret);
+	ret = register_trace_block_unplug_io(blk_add_trace_unplug_io);
+	WARN_ON(ret);
+	ret = register_trace_block_split(blk_add_trace_split);
+	WARN_ON(ret);
+	ret = register_trace_block_remap(blk_add_trace_remap);
+	WARN_ON(ret);
+	return 0;
+}
+
+static void blk_unregister_tracepoints(void)
+{
+	unregister_trace_block_remap(blk_add_trace_remap);
+	unregister_trace_block_split(blk_add_trace_split);
+	unregister_trace_block_unplug_io(blk_add_trace_unplug_io);
+	unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer);
+	unregister_trace_block_plug(blk_add_trace_plug);
+	unregister_trace_block_sleeprq(blk_add_trace_sleeprq);
+	unregister_trace_block_getrq(blk_add_trace_getrq);
+	unregister_trace_block_bio_queue(blk_add_trace_bio_queue);
+	unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge);
+	unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge);
+	unregister_trace_block_bio_complete(blk_add_trace_bio_complete);
+	unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce);
+	unregister_trace_block_rq_complete(blk_add_trace_rq_complete);
+	unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue);
+	unregister_trace_block_rq_issue(blk_add_trace_rq_issue);
+	unregister_trace_block_rq_insert(blk_add_trace_rq_insert);
+	unregister_trace_block_rq_abort(blk_add_trace_rq_abort);
+
+	tracepoint_synchronize_unregister();
+}
diff --git a/block/bsg.c b/block/bsg.c
index e73e50daf3d0..d414bb5607e8 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -42,7 +42,7 @@ struct bsg_device {
 	int done_cmds;
 	wait_queue_head_t wq_done;
 	wait_queue_head_t wq_free;
-	char name[BUS_ID_SIZE];
+	char name[20];
 	int max_queue;
 	unsigned long flags;
 };
@@ -781,7 +781,7 @@ static struct bsg_device *bsg_add_device(struct inode *inode,
 	mutex_lock(&bsg_mutex);
 	hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
 
-	strncpy(bd->name, rq->bsg_dev.class_dev->bus_id, sizeof(bd->name) - 1);
+	strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1);
 	dprintk("bound to <%s>, max queue %d\n",
 		format_dev_t(buf, inode->i_rdev), bd->max_queue);
 
@@ -992,7 +992,7 @@ int bsg_register_queue(struct request_queue *q, struct device *parent,
 	if (name)
 		devname = name;
 	else
-		devname = parent->bus_id;
+		devname = dev_name(parent);
 
 	/*
 	 * we need a proper transport to send commands, not a stacked device
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 6a062eebbd15..e8525fa72823 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1136,12 +1136,8 @@ static int cfq_dispatch_requests(struct request_queue *q, int force)
 		if (cfq_class_idle(cfqq))
 			max_dispatch = 1;
 
-		if (cfqq->dispatched >= max_dispatch) {
-			if (cfqd->busy_queues > 1)
-				break;
-			if (cfqq->dispatched >= 4 * max_dispatch)
-				break;
-		}
+		if (cfqq->dispatched >= max_dispatch && cfqd->busy_queues > 1)
+			break;
 
 		if (cfqd->sync_flight && !cfq_cfqq_sync(cfqq))
 			break;
@@ -1318,7 +1314,15 @@ static void cfq_exit_single_io_context(struct io_context *ioc,
 		unsigned long flags;
 
 		spin_lock_irqsave(q->queue_lock, flags);
-		__cfq_exit_single_io_context(cfqd, cic);
+
+		/*
+		 * Ensure we get a fresh copy of the ->key to prevent
+		 * race between exiting task and queue
+		 */
+		smp_read_barrier_depends();
+		if (cic->key)
+			__cfq_exit_single_io_context(cfqd, cic);
+
 		spin_unlock_irqrestore(q->queue_lock, flags);
 	}
 }
@@ -2160,7 +2164,7 @@ out_cont:
 static void cfq_shutdown_timer_wq(struct cfq_data *cfqd)
 {
 	del_timer_sync(&cfqd->idle_slice_timer);
-	kblockd_flush_work(&cfqd->unplug_work);
+	cancel_work_sync(&cfqd->unplug_work);
 }
 
 static void cfq_put_async_queues(struct cfq_data *cfqd)
@@ -2178,7 +2182,7 @@ static void cfq_put_async_queues(struct cfq_data *cfqd)
 		cfq_put_queue(cfqd->async_idle_cfqq);
 }
 
-static void cfq_exit_queue(elevator_t *e)
+static void cfq_exit_queue(struct elevator_queue *e)
 {
 	struct cfq_data *cfqd = e->elevator_data;
 	struct request_queue *q = cfqd->queue;
@@ -2288,7 +2292,7 @@ cfq_var_store(unsigned int *var, const char *page, size_t count)
 }
 
 #define SHOW_FUNCTION(__FUNC, __VAR, __CONV)				\
-static ssize_t __FUNC(elevator_t *e, char *page)			\
+static ssize_t __FUNC(struct elevator_queue *e, char *page)		\
 {									\
 	struct cfq_data *cfqd = e->elevator_data;			\
 	unsigned int __data = __VAR;					\
@@ -2308,7 +2312,7 @@ SHOW_FUNCTION(cfq_slice_async_rq_show, cfqd->cfq_slice_async_rq, 0);
 #undef SHOW_FUNCTION
 
 #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV)			\
-static ssize_t __FUNC(elevator_t *e, const char *page, size_t count)	\
+static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count)	\
 {									\
 	struct cfq_data *cfqd = e->elevator_data;			\
 	unsigned int __data;						\
diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index 67eb93cff699..f87615dea46b 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -774,9 +774,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 		bdi = blk_get_backing_dev_info(bdev);
 		if (bdi == NULL)
 			return -ENOTTY;
-		lock_kernel();
 		bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
-		unlock_kernel();
 		return 0;
 	case BLKGETSIZE:
 		size = bdev->bd_inode->i_size;
diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c
index fd311179f44c..c4d991d4adef 100644
--- a/block/deadline-iosched.c
+++ b/block/deadline-iosched.c
@@ -334,7 +334,7 @@ static int deadline_queue_empty(struct request_queue *q)
 		&& list_empty(&dd->fifo_list[READ]);
 }
 
-static void deadline_exit_queue(elevator_t *e)
+static void deadline_exit_queue(struct elevator_queue *e)
 {
 	struct deadline_data *dd = e->elevator_data;
 
@@ -387,7 +387,7 @@ deadline_var_store(int *var, const char *page, size_t count)
 }
 
 #define SHOW_FUNCTION(__FUNC, __VAR, __CONV)				\
-static ssize_t __FUNC(elevator_t *e, char *page)			\
+static ssize_t __FUNC(struct elevator_queue *e, char *page)		\
 {									\
 	struct deadline_data *dd = e->elevator_data;			\
 	int __data = __VAR;						\
@@ -403,7 +403,7 @@ SHOW_FUNCTION(deadline_fifo_batch_show, dd->fifo_batch, 0);
 #undef SHOW_FUNCTION
 
 #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV)			\
-static ssize_t __FUNC(elevator_t *e, const char *page, size_t count)	\
+static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count)	\
 {									\
 	struct deadline_data *dd = e->elevator_data;			\
 	int __data;							\
diff --git a/block/elevator.c b/block/elevator.c
index a6951f76ba0c..98259eda0ef6 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -33,6 +33,7 @@
 #include <linux/compiler.h>
 #include <linux/delay.h>
 #include <linux/blktrace_api.h>
+#include <trace/block.h>
 #include <linux/hash.h>
 #include <linux/uaccess.h>
 
@@ -41,6 +42,8 @@
 static DEFINE_SPINLOCK(elv_list_lock);
 static LIST_HEAD(elv_list);
 
+DEFINE_TRACE(block_rq_abort);
+
 /*
  * Merge hash stuff.
  */
@@ -52,6 +55,9 @@ static const int elv_hash_shift = 6;
 #define rq_hash_key(rq)		((rq)->sector + (rq)->nr_sectors)
 #define ELV_ON_HASH(rq)		(!hlist_unhashed(&(rq)->hash))
 
+DEFINE_TRACE(block_rq_insert);
+DEFINE_TRACE(block_rq_issue);
+
 /*
  * Query io scheduler to see if the current process issuing bio may be
  * merged with rq.
@@ -59,7 +65,7 @@ static const int elv_hash_shift = 6;
 static int elv_iosched_allow_merge(struct request *rq, struct bio *bio)
 {
 	struct request_queue *q = rq->q;
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_allow_merge_fn)
 		return e->ops->elevator_allow_merge_fn(q, rq, bio);
@@ -202,13 +208,13 @@ __setup("elevator=", elevator_setup);
 
 static struct kobj_type elv_ktype;
 
-static elevator_t *elevator_alloc(struct request_queue *q,
+static struct elevator_queue *elevator_alloc(struct request_queue *q,
 				  struct elevator_type *e)
 {
-	elevator_t *eq;
+	struct elevator_queue *eq;
 	int i;
 
-	eq = kmalloc_node(sizeof(elevator_t), GFP_KERNEL | __GFP_ZERO, q->node);
+	eq = kmalloc_node(sizeof(*eq), GFP_KERNEL | __GFP_ZERO, q->node);
 	if (unlikely(!eq))
 		goto err;
 
@@ -234,8 +240,9 @@ err:
 
 static void elevator_release(struct kobject *kobj)
 {
-	elevator_t *e = container_of(kobj, elevator_t, kobj);
+	struct elevator_queue *e;
 
+	e = container_of(kobj, struct elevator_queue, kobj);
 	elevator_put(e->elevator_type);
 	kfree(e->hash);
 	kfree(e);
@@ -291,7 +298,7 @@ int elevator_init(struct request_queue *q, char *name)
 }
 EXPORT_SYMBOL(elevator_init);
 
-void elevator_exit(elevator_t *e)
+void elevator_exit(struct elevator_queue *e)
 {
 	mutex_lock(&e->sysfs_lock);
 	if (e->ops->elevator_exit_fn)
@@ -305,7 +312,7 @@ EXPORT_SYMBOL(elevator_exit);
 
 static void elv_activate_rq(struct request_queue *q, struct request *rq)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_activate_req_fn)
 		e->ops->elevator_activate_req_fn(q, rq);
@@ -313,7 +320,7 @@ static void elv_activate_rq(struct request_queue *q, struct request *rq)
 
 static void elv_deactivate_rq(struct request_queue *q, struct request *rq)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_deactivate_req_fn)
 		e->ops->elevator_deactivate_req_fn(q, rq);
@@ -332,7 +339,7 @@ static void elv_rqhash_del(struct request_queue *q, struct request *rq)
 
 static void elv_rqhash_add(struct request_queue *q, struct request *rq)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	BUG_ON(ELV_ON_HASH(rq));
 	hlist_add_head(&rq->hash, &e->hash[ELV_HASH_FN(rq_hash_key(rq))]);
@@ -346,7 +353,7 @@ static void elv_rqhash_reposition(struct request_queue *q, struct request *rq)
 
 static struct request *elv_rqhash_find(struct request_queue *q, sector_t offset)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 	struct hlist_head *hash_list = &e->hash[ELV_HASH_FN(offset)];
 	struct hlist_node *entry, *next;
 	struct request *rq;
@@ -488,7 +495,7 @@ EXPORT_SYMBOL(elv_dispatch_add_tail);
 
 int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 	struct request *__rq;
 	int ret;
 
@@ -523,7 +530,7 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
 
 void elv_merged_request(struct request_queue *q, struct request *rq, int type)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_merged_fn)
 		e->ops->elevator_merged_fn(q, rq, type);
@@ -537,7 +544,7 @@ void elv_merged_request(struct request_queue *q, struct request *rq, int type)
 void elv_merge_requests(struct request_queue *q, struct request *rq,
 			     struct request *next)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_merge_req_fn)
 		e->ops->elevator_merge_req_fn(q, rq, next);
@@ -586,7 +593,7 @@ void elv_insert(struct request_queue *q, struct request *rq, int where)
 	unsigned ordseq;
 	int unplug_it = 1;
 
-	blk_add_trace_rq(q, rq, BLK_TA_INSERT);
+	trace_block_rq_insert(q, rq);
 
 	rq->q = q;
 
@@ -749,14 +756,6 @@ struct request *elv_next_request(struct request_queue *q)
 	int ret;
 
 	while ((rq = __elv_next_request(q)) != NULL) {
-		/*
-		 * Kill the empty barrier place holder, the driver must
-		 * not ever see it.
-		 */
-		if (blk_empty_barrier(rq)) {
-			__blk_end_request(rq, 0, blk_rq_bytes(rq));
-			continue;
-		}
 		if (!(rq->cmd_flags & REQ_STARTED)) {
 			/*
 			 * This is the first time the device driver
@@ -772,7 +771,7 @@ struct request *elv_next_request(struct request_queue *q)
 			 * not be passed by new incoming requests
 			 */
 			rq->cmd_flags |= REQ_STARTED;
-			blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
+			trace_block_rq_issue(q, rq);
 		}
 
 		if (!q->boundary_rq || q->boundary_rq == rq) {
@@ -848,7 +847,7 @@ void elv_dequeue_request(struct request_queue *q, struct request *rq)
 
 int elv_queue_empty(struct request_queue *q)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (!list_empty(&q->queue_head))
 		return 0;
@@ -862,7 +861,7 @@ EXPORT_SYMBOL(elv_queue_empty);
 
 struct request *elv_latter_request(struct request_queue *q, struct request *rq)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_latter_req_fn)
 		return e->ops->elevator_latter_req_fn(q, rq);
@@ -871,7 +870,7 @@ struct request *elv_latter_request(struct request_queue *q, struct request *rq)
 
 struct request *elv_former_request(struct request_queue *q, struct request *rq)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_former_req_fn)
 		return e->ops->elevator_former_req_fn(q, rq);
@@ -880,7 +879,7 @@ struct request *elv_former_request(struct request_queue *q, struct request *rq)
 
 int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_set_req_fn)
 		return e->ops->elevator_set_req_fn(q, rq, gfp_mask);
@@ -891,7 +890,7 @@ int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask)
 
 void elv_put_request(struct request_queue *q, struct request *rq)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_put_req_fn)
 		e->ops->elevator_put_req_fn(rq);
@@ -899,7 +898,7 @@ void elv_put_request(struct request_queue *q, struct request *rq)
 
 int elv_may_queue(struct request_queue *q, int rw)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	if (e->ops->elevator_may_queue_fn)
 		return e->ops->elevator_may_queue_fn(q, rw);
@@ -914,7 +913,7 @@ void elv_abort_queue(struct request_queue *q)
 	while (!list_empty(&q->queue_head)) {
 		rq = list_entry_rq(q->queue_head.next);
 		rq->cmd_flags |= REQ_QUIET;
-		blk_add_trace_rq(q, rq, BLK_TA_ABORT);
+		trace_block_rq_abort(q, rq);
 		__blk_end_request(rq, -EIO, blk_rq_bytes(rq));
 	}
 }
@@ -922,7 +921,7 @@ EXPORT_SYMBOL(elv_abort_queue);
 
 void elv_completed_request(struct request_queue *q, struct request *rq)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 
 	/*
 	 * request is released from the driver, io must be done
@@ -938,10 +937,14 @@ void elv_completed_request(struct request_queue *q, struct request *rq)
 	 * drained for flush sequence.
 	 */
 	if (unlikely(q->ordseq)) {
-		struct request *first_rq = list_entry_rq(q->queue_head.next);
-		if (q->in_flight == 0 &&
+		struct request *next = NULL;
+
+		if (!list_empty(&q->queue_head))
+			next = list_entry_rq(q->queue_head.next);
+
+		if (!q->in_flight &&
 		    blk_ordered_cur_seq(q) == QUEUE_ORDSEQ_DRAIN &&
-		    blk_ordered_req_seq(first_rq) > QUEUE_ORDSEQ_DRAIN) {
+		    (!next || blk_ordered_req_seq(next) > QUEUE_ORDSEQ_DRAIN)) {
 			blk_ordered_complete_seq(q, QUEUE_ORDSEQ_DRAIN, 0);
 			blk_start_queueing(q);
 		}
@@ -953,13 +956,14 @@ void elv_completed_request(struct request_queue *q, struct request *rq)
 static ssize_t
 elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
 {
-	elevator_t *e = container_of(kobj, elevator_t, kobj);
 	struct elv_fs_entry *entry = to_elv(attr);
+	struct elevator_queue *e;
 	ssize_t error;
 
 	if (!entry->show)
 		return -EIO;
 
+	e = container_of(kobj, struct elevator_queue, kobj);
 	mutex_lock(&e->sysfs_lock);
 	error = e->ops ? entry->show(e, page) : -ENOENT;
 	mutex_unlock(&e->sysfs_lock);
@@ -970,13 +974,14 @@ static ssize_t
 elv_attr_store(struct kobject *kobj, struct attribute *attr,
 	       const char *page, size_t length)
 {
-	elevator_t *e = container_of(kobj, elevator_t, kobj);
 	struct elv_fs_entry *entry = to_elv(attr);
+	struct elevator_queue *e;
 	ssize_t error;
 
 	if (!entry->store)
 		return -EIO;
 
+	e = container_of(kobj, struct elevator_queue, kobj);
 	mutex_lock(&e->sysfs_lock);
 	error = e->ops ? entry->store(e, page, length) : -ENOENT;
 	mutex_unlock(&e->sysfs_lock);
@@ -995,7 +1000,7 @@ static struct kobj_type elv_ktype = {
 
 int elv_register_queue(struct request_queue *q)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 	int error;
 
 	error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched");
@@ -1013,7 +1018,7 @@ int elv_register_queue(struct request_queue *q)
 	return error;
 }
 
-static void __elv_unregister_queue(elevator_t *e)
+static void __elv_unregister_queue(struct elevator_queue *e)
 {
 	kobject_uevent(&e->kobj, KOBJ_REMOVE);
 	kobject_del(&e->kobj);
@@ -1076,7 +1081,7 @@ EXPORT_SYMBOL_GPL(elv_unregister);
  */
 static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
 {
-	elevator_t *old_elevator, *e;
+	struct elevator_queue *old_elevator, *e;
 	void *data;
 
 	/*
@@ -1182,7 +1187,7 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name,
 
 ssize_t elv_iosched_show(struct request_queue *q, char *name)
 {
-	elevator_t *e = q->elevator;
+	struct elevator_queue *e = q->elevator;
 	struct elevator_type *elv = e->elevator_type;
 	struct elevator_type *__e;
 	int len = 0;
diff --git a/block/genhd.c b/block/genhd.c
index 2f7feda61e35..397960cf26af 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -181,6 +181,12 @@ void disk_part_iter_exit(struct disk_part_iter *piter)
 }
 EXPORT_SYMBOL_GPL(disk_part_iter_exit);
 
+static inline int sector_in_part(struct hd_struct *part, sector_t sector)
+{
+	return part->start_sect <= sector &&
+		sector < part->start_sect + part->nr_sects;
+}
+
 /**
  * disk_map_sector_rcu - map sector to partition
  * @disk: gendisk of interest
@@ -199,16 +205,22 @@ EXPORT_SYMBOL_GPL(disk_part_iter_exit);
 struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
 {
 	struct disk_part_tbl *ptbl;
+	struct hd_struct *part;
 	int i;
 
 	ptbl = rcu_dereference(disk->part_tbl);
 
+	part = rcu_dereference(ptbl->last_lookup);
+	if (part && sector_in_part(part, sector))
+		return part;
+
 	for (i = 1; i < ptbl->len; i++) {
-		struct hd_struct *part = rcu_dereference(ptbl->part[i]);
+		part = rcu_dereference(ptbl->part[i]);
 
-		if (part && part->start_sect <= sector &&
-		    sector < part->start_sect + part->nr_sects)
+		if (part && sector_in_part(part, sector)) {
+			rcu_assign_pointer(ptbl->last_lookup, part);
 			return part;
+		}
 	}
 	return &disk->part0;
 }
@@ -888,8 +900,11 @@ static void disk_replace_part_tbl(struct gendisk *disk,
 	struct disk_part_tbl *old_ptbl = disk->part_tbl;
 
 	rcu_assign_pointer(disk->part_tbl, new_ptbl);
-	if (old_ptbl)
+
+	if (old_ptbl) {
+		rcu_assign_pointer(old_ptbl->last_lookup, NULL);
 		call_rcu(&old_ptbl->rcu_head, disk_free_ptbl_rcu_cb);
+	}
 }
 
 /**
@@ -1069,7 +1084,7 @@ dev_t blk_lookup_devt(const char *name, int partno)
 		struct gendisk *disk = dev_to_disk(dev);
 		struct hd_struct *part;
 
-		if (strcmp(dev->bus_id, name))
+		if (strcmp(dev_name(dev), name))
 			continue;
 
 		part = disk_get_part(disk, partno);
diff --git a/block/ioctl.c b/block/ioctl.c
index d03985b04d67..0f22e629b13c 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -323,9 +323,7 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 		bdi = blk_get_backing_dev_info(bdev);
 		if (bdi == NULL)
 			return -ENOTTY;
-		lock_kernel();
 		bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
-		unlock_kernel();
 		return 0;
 	case BLKBSZSET:
 		/* set the logical block size */
diff --git a/block/noop-iosched.c b/block/noop-iosched.c
index c23e02969650..3a0d369d08c7 100644
--- a/block/noop-iosched.c
+++ b/block/noop-iosched.c
@@ -76,7 +76,7 @@ static void *noop_init_queue(struct request_queue *q)
 	return nd;
 }
 
-static void noop_exit_queue(elevator_t *e)
+static void noop_exit_queue(struct elevator_queue *e)
 {
 	struct noop_data *nd = e->elevator_data;
 
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index d0bb92cbefb9..ee9c67d7e1be 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -60,7 +60,7 @@ static int scsi_get_bus(struct request_queue *q, int __user *p)
 
 static int sg_get_timeout(struct request_queue *q)
 {
-	return q->sg_timeout / (HZ / USER_HZ);
+	return jiffies_to_clock_t(q->sg_timeout);
 }
 
 static int sg_set_timeout(struct request_queue *q, int __user *p)
@@ -68,7 +68,7 @@ static int sg_set_timeout(struct request_queue *q, int __user *p)
 	int timeout, err = get_user(timeout, p);
 
 	if (!err)
-		q->sg_timeout = timeout * (HZ / USER_HZ);
+		q->sg_timeout = clock_t_to_jiffies(timeout);
 
 	return err;
 }