Merge branch 'for-4.2/core' of git://git.kernel.dk/linux-block

Pull core block IO update from Jens Axboe:
 "Nothing really major in here, mostly a collection of smaller
  optimizations and cleanups, mixed with various fixes.  In more detail,
  this contains:

   - Addition of policy specific data to blkcg for block cgroups.  From
     Arianna Avanzini.

   - Various cleanups around command types from Christoph.

   - Cleanup of the suspend block I/O path from Christoph.

   - Plugging updates from Shaohua and Jeff Moyer, for blk-mq.

   - Eliminating atomic inc/dec of both remaining IO count and reference
     count in a bio.  From me.

   - Fixes for SG gap and chunk size support for data-less (discards)
     IO, so we can merge these better.  From me.

   - Small restructuring of blk-mq shared tag support, freeing drivers
     from iterating hardware queues.  From Keith Busch.

   - A few cfq-iosched tweaks, from Tahsin Erdogan and me.  Makes the
     IOPS mode the default for non-rotational storage"

* 'for-4.2/core' of git://git.kernel.dk/linux-block: (35 commits)
  cfq-iosched: fix other locations where blkcg_to_cfqgd() can return NULL
  cfq-iosched: fix sysfs oops when attempting to read unconfigured weights
  cfq-iosched: move group scheduling functions under ifdef
  cfq-iosched: fix the setting of IOPS mode on SSDs
  blktrace: Add blktrace.c to BLOCK LAYER in MAINTAINERS file
  block, cgroup: implement policy-specific per-blkcg data
  block: Make CFQ default to IOPS mode on SSDs
  block: add blk_set_queue_dying() to blkdev.h
  blk-mq: Shared tag enhancements
  block: don't honor chunk sizes for data-less IO
  block: only honor SG gap prevention for merges that contain data
  block: fix returnvar.cocci warnings
  block, dm: don't copy bios for request clones
  block: remove management of bi_remaining when restoring original bi_end_io
  block: replace trylock with mutex_lock in blkdev_reread_part()
  block: export blkdev_reread_part() and __blkdev_reread_part()
  suspend: simplify block I/O handling
  block: collapse bio bit space
  block: remove unused BIO_RW_BLOCK and BIO_EOF flags
  block: remove BIO_EOPNOTSUPP
  ...

include/linux/blkdev.h

@@ -30,7 +30,6 @@ struct scsi_ioctl_command;
 
 struct request_queue;
 struct elevator_queue;
-struct request_pm_state;
 struct blk_trace;
 struct request;
 struct sg_io_hdr;
@@ -75,18 +74,7 @@ struct request_list {
 enum rq_cmd_type_bits {
 	REQ_TYPE_FS		= 1,	/* fs request */
 	REQ_TYPE_BLOCK_PC,		/* scsi command */
-	REQ_TYPE_SENSE,			/* sense request */
-	REQ_TYPE_PM_SUSPEND,		/* suspend request */
-	REQ_TYPE_PM_RESUME,		/* resume request */
-	REQ_TYPE_PM_SHUTDOWN,		/* shutdown request */
-	REQ_TYPE_SPECIAL,		/* driver defined type */
-	/*
-	 * for ATA/ATAPI devices. this really doesn't belong here, ide should
-	 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
-	 * private REQ_LB opcodes to differentiate what type of request this is
-	 */
-	REQ_TYPE_ATA_TASKFILE,
-	REQ_TYPE_ATA_PC,
+	REQ_TYPE_DRV_PRIV,		/* driver defined types from here */
 };
 
 #define BLK_MAX_CDB	16
@@ -108,7 +96,7 @@ struct request {
 	struct blk_mq_ctx *mq_ctx;
 
 	u64 cmd_flags;
-	enum rq_cmd_type_bits cmd_type;
+	unsigned cmd_type;
 	unsigned long atomic_flags;
 
 	int cpu;
@@ -216,19 +204,6 @@ static inline unsigned short req_get_ioprio(struct request *req)
 	return req->ioprio;
 }
 
-/*
- * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
- * requests. Some step values could eventually be made generic.
- */
-struct request_pm_state
-{
-	/* PM state machine step value, currently driver specific */
-	int	pm_step;
-	/* requested PM state value (S1, S2, S3, S4, ...) */
-	u32	pm_state;
-	void*	data;		/* for driver use */
-};
-
 #include <linux/elevator.h>
 
 struct blk_queue_ctx;
@@ -469,7 +444,7 @@ struct request_queue {
 	struct mutex		sysfs_lock;
 
 	int			bypass_depth;
-	int			mq_freeze_depth;
+	atomic_t		mq_freeze_depth;
 
 #if defined(CONFIG_BLK_DEV_BSG)
 	bsg_job_fn		*bsg_job_fn;
@@ -610,10 +585,6 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 	(((rq)->cmd_flags & REQ_STARTED) && \
 	 ((rq)->cmd_type == REQ_TYPE_FS))
 
-#define blk_pm_request(rq)	\
-	((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
-	 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
-
 #define blk_rq_cpu_valid(rq)	((rq)->cpu != -1)
 #define blk_bidi_rq(rq)		((rq)->next_rq != NULL)
 /* rq->queuelist of dequeued request must be list_empty() */
@@ -804,11 +775,7 @@ extern void blk_add_request_payload(struct request *rq, struct page *page,
 		unsigned int len);
 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
 extern int blk_lld_busy(struct request_queue *q);
-extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
-			     struct bio_set *bs, gfp_t gfp_mask,
-			     int (*bio_ctr)(struct bio *, struct bio *, void *),
-			     void *data);
-extern void blk_rq_unprep_clone(struct request *rq);
+extern void blk_rq_prep_clone(struct request *rq, struct request *rq_src);
 extern int blk_insert_cloned_request(struct request_queue *q,
 				     struct request *rq);
 extern void blk_delay_queue(struct request_queue *, unsigned long);
@@ -845,6 +812,7 @@ extern void blk_stop_queue(struct request_queue *q);
 extern void blk_sync_queue(struct request_queue *q);
 extern void __blk_stop_queue(struct request_queue *q);
 extern void __blk_run_queue(struct request_queue *q);
+extern void __blk_run_queue_uncond(struct request_queue *q);
 extern void blk_run_queue(struct request_queue *);
 extern void blk_run_queue_async(struct request_queue *q);
 extern int blk_rq_map_user(struct request_queue *, struct request *,
@@ -933,7 +901,7 @@ static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
 	if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
 		return q->limits.max_hw_sectors;
 
-	if (!q->limits.chunk_sectors)
+	if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
 		return blk_queue_get_max_sectors(q, rq->cmd_flags);
 
 	return min(blk_max_size_offset(q, blk_rq_pos(rq)),
@@ -1054,6 +1022,7 @@ bool __must_check blk_get_queue(struct request_queue *);
 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 *);
+extern void blk_set_queue_dying(struct request_queue *);
 
 /*
  * block layer runtime pm functions