Merge branch 'for-linus' of git://git.kernel.dk/linux-block

* 'for-linus' of git://git.kernel.dk/linux-block: (23 commits)
  Revert "cfq: Remove special treatment for metadata rqs."
  block: fix flush machinery for stacking drivers with differring flush flags
  block: improve rq_affinity placement
  blktrace: add FLUSH/FUA support
  Move some REQ flags to the common bio/request area
  allow blk_flush_policy to return REQ_FSEQ_DATA independent of *FLUSH
  xen/blkback: Make description more obvious.
  cfq-iosched: Add documentation about idling
  block: Make rq_affinity = 1 work as expected
  block: swim3: fix unterminated of_device_id table
  block/genhd.c: remove useless cast in diskstats_show()
  drivers/cdrom/cdrom.c: relax check on dvd manufacturer value
  drivers/block/drbd/drbd_nl.c: use bitmap_parse instead of __bitmap_parse
  bsg-lib: add module.h include
  cfq-iosched: Reduce linked group count upon group destruction
  blk-throttle: correctly determine sync bio
  loop: fix deadlock when sysfs and LOOP_CLR_FD race against each other
  loop: add BLK_DEV_LOOP_MIN_COUNT=%i to allow distros 0 pre-allocated loop devices
  loop: add management interface for on-demand device allocation
  loop: replace linked list of allocated devices with an idr index
  ...

7 files changed, 101 insertions, 15 deletions

diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 6395692b2e7a..32f0076e844b 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -125,7 +125,11 @@ enum rq_flag_bits {
 	__REQ_SYNC,		/* request is sync (sync write or read) */
 	__REQ_META,		/* metadata io request */
 	__REQ_DISCARD,		/* request to discard sectors */
+	__REQ_SECURE,		/* secure discard (used with __REQ_DISCARD) */
+
 	__REQ_NOIDLE,		/* don't anticipate more IO after this one */
+	__REQ_FUA,		/* forced unit access */
+	__REQ_FLUSH,		/* request for cache flush */
 
 	/* bio only flags */
 	__REQ_RAHEAD,		/* read ahead, can fail anytime */
@@ -135,7 +139,6 @@ enum rq_flag_bits {
 	/* request only flags */
 	__REQ_SORTED,		/* elevator knows about this request */
 	__REQ_SOFTBARRIER,	/* may not be passed by ioscheduler */
-	__REQ_FUA,		/* forced unit access */
 	__REQ_NOMERGE,		/* don't touch this for merging */
 	__REQ_STARTED,		/* drive already may have started this one */
 	__REQ_DONTPREP,		/* don't call prep for this one */
@@ -146,11 +149,9 @@ enum rq_flag_bits {
 	__REQ_PREEMPT,		/* set for "ide_preempt" requests */
 	__REQ_ALLOCED,		/* request came from our alloc pool */
 	__REQ_COPY_USER,	/* contains copies of user pages */
-	__REQ_FLUSH,		/* request for cache flush */
 	__REQ_FLUSH_SEQ,	/* request for flush sequence */
 	__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_NR_BITS,		/* stops here */
 };
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 0e67c45b3bc9..84b15d54f8c2 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -30,6 +30,7 @@ struct request_pm_state;
 struct blk_trace;
 struct request;
 struct sg_io_hdr;
+struct bsg_job;
 
 #define BLKDEV_MIN_RQ	4
 #define BLKDEV_MAX_RQ	128	/* Default maximum */
@@ -117,6 +118,7 @@ struct request {
 		struct {
 			unsigned int		seq;
 			struct list_head	list;
+			rq_end_io_fn		*saved_end_io;
 		} flush;
 	};
 
@@ -209,6 +211,7 @@ typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
 typedef void (softirq_done_fn)(struct request *);
 typedef int (dma_drain_needed_fn)(struct request *);
 typedef int (lld_busy_fn) (struct request_queue *q);
+typedef int (bsg_job_fn) (struct bsg_job *);
 
 enum blk_eh_timer_return {
 	BLK_EH_NOT_HANDLED,
@@ -375,6 +378,8 @@ struct request_queue {
 	struct mutex		sysfs_lock;
 
 #if defined(CONFIG_BLK_DEV_BSG)
+	bsg_job_fn		*bsg_job_fn;
+	int			bsg_job_size;
 	struct bsg_class_device bsg_dev;
 #endif
 
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 8c7c2de7631a..8e9e4bc6d73b 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -14,7 +14,7 @@
 enum blktrace_cat {
 	BLK_TC_READ	= 1 << 0,	/* reads */
 	BLK_TC_WRITE	= 1 << 1,	/* writes */
-	BLK_TC_BARRIER	= 1 << 2,	/* barrier */
+	BLK_TC_FLUSH	= 1 << 2,	/* flush */
 	BLK_TC_SYNC	= 1 << 3,	/* sync IO */
 	BLK_TC_SYNCIO	= BLK_TC_SYNC,
 	BLK_TC_QUEUE	= 1 << 4,	/* queueing/merging */
@@ -28,8 +28,9 @@ enum blktrace_cat {
 	BLK_TC_META	= 1 << 12,	/* metadata */
 	BLK_TC_DISCARD	= 1 << 13,	/* discard requests */
 	BLK_TC_DRV_DATA	= 1 << 14,	/* binary per-driver data */
+	BLK_TC_FUA	= 1 << 15,	/* fua requests */
 
-	BLK_TC_END	= 1 << 15,	/* only 16-bits, reminder */
+	BLK_TC_END	= 1 << 15,	/* we've run out of bits! */
 };
 
 #define BLK_TC_SHIFT		(16)
diff --git a/include/linux/bsg-lib.h b/include/linux/bsg-lib.h
new file mode 100644
index 000000000000..f55ab8cdc106
--- /dev/null
+++ b/include/linux/bsg-lib.h
@@ -0,0 +1,73 @@
+/*
+ *  BSG helper library
+ *
+ *  Copyright (C) 2008   James Smart, Emulex Corporation
+ *  Copyright (C) 2011   Red Hat, Inc.  All rights reserved.
+ *  Copyright (C) 2011   Mike Christie
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+#ifndef _BLK_BSG_
+#define _BLK_BSG_
+
+#include <linux/blkdev.h>
+
+struct request;
+struct device;
+struct scatterlist;
+struct request_queue;
+
+struct bsg_buffer {
+	unsigned int payload_len;
+	int sg_cnt;
+	struct scatterlist *sg_list;
+};
+
+struct bsg_job {
+	struct device *dev;
+	struct request *req;
+
+	/* Transport/driver specific request/reply structs */
+	void *request;
+	void *reply;
+
+	unsigned int request_len;
+	unsigned int reply_len;
+	/*
+	 * On entry : reply_len indicates the buffer size allocated for
+	 * the reply.
+	 *
+	 * Upon completion : the message handler must set reply_len
+	 *  to indicates the size of the reply to be returned to the
+	 *  caller.
+	 */
+
+	/* DMA payloads for the request/response */
+	struct bsg_buffer request_payload;
+	struct bsg_buffer reply_payload;
+
+	void *dd_data;		/* Used for driver-specific storage */
+};
+
+void bsg_job_done(struct bsg_job *job, int result,
+		  unsigned int reply_payload_rcv_len);
+int bsg_setup_queue(struct device *dev, struct request_queue *q, char *name,
+		    bsg_job_fn *job_fn, int dd_job_size);
+void bsg_request_fn(struct request_queue *q);
+void bsg_remove_queue(struct request_queue *q);
+void bsg_goose_queue(struct request_queue *q);
+
+#endif
diff --git a/include/linux/loop.h b/include/linux/loop.h
index 66c194e2d9b9..683d69890119 100644
--- a/include/linux/loop.h
+++ b/include/linux/loop.h
@@ -64,7 +64,6 @@ struct loop_device {
 
 	struct request_queue	*lo_queue;
 	struct gendisk		*lo_disk;
-	struct list_head	lo_list;
 };
 
 #endif /* __KERNEL__ */
@@ -161,4 +160,8 @@ int loop_unregister_transfer(int number);
 #define LOOP_CHANGE_FD		0x4C06
 #define LOOP_SET_CAPACITY	0x4C07
 
+/* /dev/loop-control interface */
+#define LOOP_CTL_ADD		0x4C80
+#define LOOP_CTL_REMOVE		0x4C81
+#define LOOP_CTL_GET_FREE	0x4C82
 #endif
diff --git a/include/linux/miscdevice.h b/include/linux/miscdevice.h
index 18fd13028ba1..c309b1ecdc1c 100644
--- a/include/linux/miscdevice.h
+++ b/include/linux/miscdevice.h
@@ -40,6 +40,7 @@
 #define BTRFS_MINOR		234
 #define AUTOFS_MINOR		235
 #define MAPPER_CTRL_MINOR	236
+#define LOOP_CTRL_MINOR		237
 #define MISC_DYNAMIC_MINOR	255
 
 struct device;
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index bf366547da25..05c5e61f0a7c 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -8,6 +8,8 @@
 #include <linux/blkdev.h>
 #include <linux/tracepoint.h>
 
+#define RWBS_LEN	8
+
 DECLARE_EVENT_CLASS(block_rq_with_error,
 
 	TP_PROTO(struct request_queue *q, struct request *rq),
@@ -19,7 +21,7 @@ DECLARE_EVENT_CLASS(block_rq_with_error,
 		__field(  sector_t,	sector			)
 		__field(  unsigned int,	nr_sector		)
 		__field(  int,		errors			)
-		__array(  char,		rwbs,	6		)
+		__array(  char,		rwbs,	RWBS_LEN	)
 		__dynamic_array( char,	cmd,	blk_cmd_buf_len(rq)	)
 	),
 
@@ -104,7 +106,7 @@ DECLARE_EVENT_CLASS(block_rq,
 		__field(  sector_t,	sector			)
 		__field(  unsigned int,	nr_sector		)
 		__field(  unsigned int,	bytes			)
-		__array(  char,		rwbs,	6		)
+		__array(  char,		rwbs,	RWBS_LEN	)
 		__array(  char,         comm,   TASK_COMM_LEN   )
 		__dynamic_array( char,	cmd,	blk_cmd_buf_len(rq)	)
 	),
@@ -183,7 +185,7 @@ TRACE_EVENT(block_bio_bounce,
 		__field( dev_t,		dev			)
 		__field( sector_t,	sector			)
 		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	6		)
+		__array( char,		rwbs,	RWBS_LEN	)
 		__array( char,		comm,	TASK_COMM_LEN	)
 	),
 
@@ -222,7 +224,7 @@ TRACE_EVENT(block_bio_complete,
 		__field( sector_t,	sector		)
 		__field( unsigned,	nr_sector	)
 		__field( int,		error		)
-		__array( char,		rwbs,	6	)
+		__array( char,		rwbs,	RWBS_LEN)
 	),
 
 	TP_fast_assign(
@@ -249,7 +251,7 @@ DECLARE_EVENT_CLASS(block_bio,
 		__field( dev_t,		dev			)
 		__field( sector_t,	sector			)
 		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	6		)
+		__array( char,		rwbs,	RWBS_LEN	)
 		__array( char,		comm,	TASK_COMM_LEN	)
 	),
 
@@ -321,7 +323,7 @@ DECLARE_EVENT_CLASS(block_get_rq,
 		__field( dev_t,		dev			)
 		__field( sector_t,	sector			)
 		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	6		)
+		__array( char,		rwbs,	RWBS_LEN	)
 		__array( char,		comm,	TASK_COMM_LEN	)
         ),
 
@@ -456,7 +458,7 @@ TRACE_EVENT(block_split,
 		__field( dev_t,		dev				)
 		__field( sector_t,	sector				)
 		__field( sector_t,	new_sector			)
-		__array( char,		rwbs,		6		)
+		__array( char,		rwbs,		RWBS_LEN	)
 		__array( char,		comm,		TASK_COMM_LEN	)
 	),
 
@@ -498,7 +500,7 @@ TRACE_EVENT(block_bio_remap,
 		__field( unsigned int,	nr_sector	)
 		__field( dev_t,		old_dev		)
 		__field( sector_t,	old_sector	)
-		__array( char,		rwbs,	6	)
+		__array( char,		rwbs,	RWBS_LEN)
 	),
 
 	TP_fast_assign(
@@ -542,7 +544,7 @@ TRACE_EVENT(block_rq_remap,
 		__field( unsigned int,	nr_sector	)
 		__field( dev_t,		old_dev		)
 		__field( sector_t,	old_sector	)
-		__array( char,		rwbs,	6	)
+		__array( char,		rwbs,	RWBS_LEN)
 	),
 
 	TP_fast_assign(