Merge branch 'for-4.12/block' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:

 - Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
   was initially a fork of CFQ, but subsequently changed to implement
   fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
   to be used on desktop type single drives, providing good fairness.
   From Paolo.

 - Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
   using a scalable token based algorithm that throttles IO based on
   live completion IO stats, similary to blk-wbt. From Omar.

 - A series from Jan, moving users to separately allocated backing
   devices. This continues the work of separating backing device life
   times, solving various problems with hot removal.

 - A series of updates for lightnvm, mostly from Javier. Includes a
   'pblk' target that exposes an open channel SSD as a physical block
   device.

 - A series of fixes and improvements for nbd from Josef.

 - A series from Omar, removing queue sharing between devices on mostly
   legacy drivers. This helps us clean up other bits, if we know that a
   queue only has a single device backing. This has been overdue for
   more than a decade.

 - Fixes for the blk-stats, and improvements to unify the stats and user
   windows. This both improves blk-wbt, and enables other users to
   register a need to receive IO stats for a device. From Omar.

 - blk-throttle improvements from Shaohua. This provides a scalable
   framework for implementing scalable priotization - particularly for
   blk-mq, but applicable to any type of block device. The interface is
   marked experimental for now.

 - Bucketized IO stats for IO polling from Stephen Bates. This improves
   efficiency of polled workloads in the presence of mixed block size
   IO.

 - A few fixes for opal, from Scott.

 - A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
   From a variety of folks, mostly Sagi and James Smart.

 - A series from Bart, improving our exposed info and capabilities from
   the blk-mq debugfs support.

 - A series from Christoph, cleaning up how handle WRITE_ZEROES.

 - A series from Christoph, cleaning up the block layer handling of how
   we track errors in a request. On top of being a nice cleanup, it also
   shrinks the size of struct request a bit.

 - Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
   never used by platforms, and the latter has outlived it's usefulness.

 - Various little bug fixes and cleanups from a wide variety of folks.

* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
  block: hide badblocks attribute by default
  blk-mq: unify hctx delay_work and run_work
  block: add kblock_mod_delayed_work_on()
  blk-mq: unify hctx delayed_run_work and run_work
  nbd: fix use after free on module unload
  MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
  blk-mq-sched: alloate reserved tags out of normal pool
  mtip32xx: use runtime tag to initialize command header
  scsi: Implement blk_mq_ops.show_rq()
  blk-mq: Add blk_mq_ops.show_rq()
  blk-mq: Show operation, cmd_flags and rq_flags names
  blk-mq: Make blk_flags_show() callers append a newline character
  blk-mq: Move the "state" debugfs attribute one level down
  blk-mq: Unregister debugfs attributes earlier
  blk-mq: Only unregister hctxs for which registration succeeded
  blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
  blk-mq: Let blk_mq_debugfs_register() look up the queue name
  blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
  ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
  ide-pm: always pass 0 error to __blk_end_request_all
  ..

29 files changed, 447 insertions, 248 deletions

diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index ad955817916d..866c433e7d32 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -21,6 +21,7 @@ struct dentry;
  */
 enum wb_state {
 	WB_registered,		/* bdi_register() was done */
+	WB_shutting_down,	/* wb_shutdown() in progress */
 	WB_writeback_running,	/* Writeback is in progress */
 	WB_has_dirty_io,	/* Dirty inodes on ->b_{dirty|io|more_io} */
 };
@@ -54,7 +55,9 @@ struct bdi_writeback_congested {
 	atomic_t refcnt;		/* nr of attached wb's and blkg */
 
 #ifdef CONFIG_CGROUP_WRITEBACK
-	struct backing_dev_info *bdi;	/* the associated bdi */
+	struct backing_dev_info *__bdi;	/* the associated bdi, set to NULL
+					 * on bdi unregistration. For memcg-wb
+					 * internal use only! */
 	int blkcg_id;			/* ID of the associated blkcg */
 	struct rb_node rb_node;		/* on bdi->cgwb_congestion_tree */
 #endif
@@ -143,7 +146,7 @@ struct backing_dev_info {
 	congested_fn *congested_fn; /* Function pointer if device is md/dm */
 	void *congested_data;	/* Pointer to aux data for congested func */
 
-	char *name;
+	const char *name;
 
 	struct kref refcnt;	/* Reference counter for the structure */
 	unsigned int capabilities; /* Device capabilities */
@@ -161,7 +164,6 @@ struct backing_dev_info {
 #ifdef CONFIG_CGROUP_WRITEBACK
 	struct radix_tree_root cgwb_tree; /* radix tree of active cgroup wbs */
 	struct rb_root cgwb_congested_tree; /* their congested states */
-	atomic_t usage_cnt; /* counts both cgwbs and cgwb_contested's */
 #else
 	struct bdi_writeback_congested *wb_congested;
 #endif
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index c52a48cb9a66..557d84063934 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -17,8 +17,6 @@
 #include <linux/backing-dev-defs.h>
 #include <linux/slab.h>
 
-int __must_check bdi_init(struct backing_dev_info *bdi);
-
 static inline struct backing_dev_info *bdi_get(struct backing_dev_info *bdi)
 {
 	kref_get(&bdi->refcnt);
@@ -27,16 +25,18 @@ static inline struct backing_dev_info *bdi_get(struct backing_dev_info *bdi)
 
 void bdi_put(struct backing_dev_info *bdi);
 
-__printf(3, 4)
-int bdi_register(struct backing_dev_info *bdi, struct device *parent,
-		const char *fmt, ...);
-int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
+__printf(2, 3)
+int bdi_register(struct backing_dev_info *bdi, const char *fmt, ...);
+int bdi_register_va(struct backing_dev_info *bdi, const char *fmt,
+		    va_list args);
 int bdi_register_owner(struct backing_dev_info *bdi, struct device *owner);
 void bdi_unregister(struct backing_dev_info *bdi);
 
-int __must_check bdi_setup_and_register(struct backing_dev_info *, char *);
-void bdi_destroy(struct backing_dev_info *bdi);
 struct backing_dev_info *bdi_alloc_node(gfp_t gfp_mask, int node_id);
+static inline struct backing_dev_info *bdi_alloc(gfp_t gfp_mask)
+{
+	return bdi_alloc_node(gfp_mask, NUMA_NO_NODE);
+}
 
 void wb_start_writeback(struct bdi_writeback *wb, long nr_pages,
 			bool range_cyclic, enum wb_reason reason);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 8e521194f6fc..4931756d86d9 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -383,7 +383,7 @@ extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
 extern void bioset_free(struct bio_set *);
 extern mempool_t *biovec_create_pool(int pool_entries);
 
-extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
+extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
 extern void bio_put(struct bio *);
 
 extern void __bio_clone_fast(struct bio *, struct bio *);
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 9382c5da7a2e..f3e5e1de1bdb 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -15,7 +15,7 @@ struct blk_mq_hw_ctx {
 		unsigned long		state;		/* BLK_MQ_S_* flags */
 	} ____cacheline_aligned_in_smp;
 
-	struct work_struct	run_work;
+	struct delayed_work	run_work;
 	cpumask_var_t		cpumask;
 	int			next_cpu;
 	int			next_cpu_batch;
@@ -51,9 +51,6 @@ struct blk_mq_hw_ctx {
 
 	atomic_t		nr_active;
 
-	struct delayed_work	delayed_run_work;
-	struct delayed_work	delay_work;
-
 	struct hlist_node	cpuhp_dead;
 	struct kobject		kobj;
 
@@ -82,7 +79,6 @@ struct blk_mq_tag_set {
 
 struct blk_mq_queue_data {
 	struct request *rq;
-	struct list_head *list;
 	bool last;
 };
 
@@ -143,6 +139,14 @@ struct blk_mq_ops {
 	reinit_request_fn	*reinit_request;
 
 	map_queues_fn		*map_queues;
+
+#ifdef CONFIG_BLK_DEBUG_FS
+	/*
+	 * Used by the debugfs implementation to show driver-specific
+	 * information about a request.
+	 */
+	void (*show_rq)(struct seq_file *m, struct request *rq);
+#endif
 };
 
 enum {
@@ -153,7 +157,6 @@ enum {
 	BLK_MQ_F_SHOULD_MERGE	= 1 << 0,
 	BLK_MQ_F_TAG_SHARED	= 1 << 1,
 	BLK_MQ_F_SG_MERGE	= 1 << 2,
-	BLK_MQ_F_DEFER_ISSUE	= 1 << 4,
 	BLK_MQ_F_BLOCKING	= 1 << 5,
 	BLK_MQ_F_NO_SCHED	= 1 << 6,
 	BLK_MQ_F_ALLOC_POLICY_START_BIT = 8,
@@ -163,6 +166,7 @@ enum {
 	BLK_MQ_S_TAG_ACTIVE	= 1,
 	BLK_MQ_S_SCHED_RESTART	= 2,
 	BLK_MQ_S_TAG_WAITING	= 3,
+	BLK_MQ_S_START_ON_RUN	= 4,
 
 	BLK_MQ_MAX_DEPTH	= 10240,
 
@@ -230,7 +234,7 @@ void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
 void blk_mq_kick_requeue_list(struct request_queue *q);
 void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs);
 void blk_mq_abort_requeue_list(struct request_queue *q);
-void blk_mq_complete_request(struct request *rq, int error);
+void blk_mq_complete_request(struct request *rq);
 
 bool blk_mq_queue_stopped(struct request_queue *q);
 void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx);
@@ -240,13 +244,14 @@ void blk_mq_start_hw_queues(struct request_queue *q);
 void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
 void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
 void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
+void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
 void blk_mq_run_hw_queues(struct request_queue *q, bool async);
 void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
 void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
 		busy_tag_iter_fn *fn, void *priv);
 void blk_mq_freeze_queue(struct request_queue *q);
 void blk_mq_unfreeze_queue(struct request_queue *q);
-void blk_mq_freeze_queue_start(struct request_queue *q);
+void blk_freeze_queue_start(struct request_queue *q);
 void blk_mq_freeze_queue_wait(struct request_queue *q);
 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
 				     unsigned long timeout);
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index d703acb55d0f..61339bc44400 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -17,6 +17,10 @@ struct io_context;
 struct cgroup_subsys_state;
 typedef void (bio_end_io_t) (struct bio *);
 
+struct blk_issue_stat {
+	u64 stat;
+};
+
 /*
  * main unit of I/O for the block layer and lower layers (ie drivers and
  * stacking drivers)
@@ -29,7 +33,7 @@ struct bio {
 						 * top bits REQ_OP. Use
 						 * accessors.
 						 */
-	unsigned short		bi_flags;	/* status, command, etc */
+	unsigned short		bi_flags;	/* status, etc and bvec pool number */
 	unsigned short		bi_ioprio;
 
 	struct bvec_iter	bi_iter;
@@ -58,6 +62,10 @@ struct bio {
 	 */
 	struct io_context	*bi_ioc;
 	struct cgroup_subsys_state *bi_css;
+#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
+	void			*bi_cg_private;
+	struct blk_issue_stat	bi_issue_stat;
+#endif
 #endif
 	union {
 #if defined(CONFIG_BLK_DEV_INTEGRITY)
@@ -102,12 +110,9 @@ struct bio {
 #define BIO_REFFED	8	/* bio has elevated ->bi_cnt */
 #define BIO_THROTTLED	9	/* This bio has already been subjected to
 				 * throttling rules. Don't do it again. */
-
-/*
- * Flags starting here get preserved by bio_reset() - this includes
- * BVEC_POOL_IDX()
- */
-#define BIO_RESET_BITS	10
+#define BIO_TRACE_COMPLETION 10	/* bio_endio() should trace the final completion
+				 * of this bio. */
+/* See BVEC_POOL_OFFSET below before adding new flags */
 
 /*
  * We support 6 different bvec pools, the last one is magic in that it
@@ -117,13 +122,22 @@ struct bio {
 #define BVEC_POOL_MAX		(BVEC_POOL_NR - 1)
 
 /*
- * Top 4 bits of bio flags indicate the pool the bvecs came from.  We add
+ * Top 3 bits of bio flags indicate the pool the bvecs came from.  We add
  * 1 to the actual index so that 0 indicates that there are no bvecs to be
  * freed.
  */
-#define BVEC_POOL_BITS		(4)
+#define BVEC_POOL_BITS		(3)
 #define BVEC_POOL_OFFSET	(16 - BVEC_POOL_BITS)
 #define BVEC_POOL_IDX(bio)	((bio)->bi_flags >> BVEC_POOL_OFFSET)
+#if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1)
+# error "BVEC_POOL_BITS is too small"
+#endif
+
+/*
+ * Flags starting here get preserved by bio_reset() - this includes
+ * only BVEC_POOL_IDX()
+ */
+#define BIO_RESET_BITS	BVEC_POOL_OFFSET
 
 /*
  * Operations and flags common to the bio and request structures.
@@ -160,7 +174,7 @@ enum req_opf {
 	/* write the same sector many times */
 	REQ_OP_WRITE_SAME	= 7,
 	/* write the zero filled sector many times */
-	REQ_OP_WRITE_ZEROES	= 8,
+	REQ_OP_WRITE_ZEROES	= 9,
 
 	/* SCSI passthrough using struct scsi_request */
 	REQ_OP_SCSI_IN		= 32,
@@ -187,6 +201,10 @@ enum req_flag_bits {
 	__REQ_PREFLUSH,		/* request for cache flush */
 	__REQ_RAHEAD,		/* read ahead, can fail anytime */
 	__REQ_BACKGROUND,	/* background IO */
+
+	/* command specific flags for REQ_OP_WRITE_ZEROES: */
+	__REQ_NOUNMAP,		/* do not free blocks when zeroing */
+
 	__REQ_NR_BITS,		/* stops here */
 };
 
@@ -204,6 +222,8 @@ enum req_flag_bits {
 #define REQ_RAHEAD		(1ULL << __REQ_RAHEAD)
 #define REQ_BACKGROUND		(1ULL << __REQ_BACKGROUND)
 
+#define REQ_NOUNMAP		(1ULL << __REQ_NOUNMAP)
+
 #define REQ_FAILFAST_MASK \
 	(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
 
@@ -283,12 +303,6 @@ static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
 	return (cookie & BLK_QC_T_INTERNAL) != 0;
 }
 
-struct blk_issue_stat {
-	u64 time;
-};
-
-#define BLK_RQ_STAT_BATCH	64
-
 struct blk_rq_stat {
 	s64 mean;
 	u64 min;
@@ -296,7 +310,6 @@ struct blk_rq_stat {
 	s32 nr_samples;
 	s32 nr_batch;
 	u64 batch;
-	s64 time;
 };
 
 #endif /* __LINUX_BLK_TYPES_H */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 01a696b0a4d3..83d28623645f 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -40,15 +40,20 @@ struct blkcg_gq;
 struct blk_flush_queue;
 struct pr_ops;
 struct rq_wb;
+struct blk_queue_stats;
+struct blk_stat_callback;
 
 #define BLKDEV_MIN_RQ	4
 #define BLKDEV_MAX_RQ	128	/* Default maximum */
 
+/* Must be consisitent with blk_mq_poll_stats_bkt() */
+#define BLK_MQ_POLL_STATS_BKTS 16
+
 /*
  * Maximum number of blkcg policies allowed to be registered concurrently.
  * Defined here to simplify include dependency.
  */
-#define BLKCG_MAX_POLS		2
+#define BLKCG_MAX_POLS		3
 
 typedef void (rq_end_io_fn)(struct request *, int);
 
@@ -173,6 +178,7 @@ struct request {
 		struct rb_node rb_node;	/* sort/lookup */
 		struct bio_vec special_vec;
 		void *completion_data;
+		int error_count; /* for legacy drivers, don't use */
 	};
 
 	/*
@@ -213,16 +219,14 @@ struct request {
 
 	unsigned short ioprio;
 
-	void *special;		/* opaque pointer available for LLD use */
+	unsigned int timeout;
 
-	int errors;
+	void *special;		/* opaque pointer available for LLD use */
 
 	unsigned int extra_len;	/* length of alignment and padding */
 
 	unsigned long deadline;
 	struct list_head timeout_list;
-	unsigned int timeout;
-	int retries;
 
 	/*
 	 * completion callback.
@@ -337,7 +341,6 @@ struct queue_limits {
 	unsigned char		misaligned;
 	unsigned char		discard_misaligned;
 	unsigned char		cluster;
-	unsigned char		discard_zeroes_data;
 	unsigned char		raid_partial_stripes_expensive;
 	enum blk_zoned_model	zoned;
 };
@@ -388,6 +391,7 @@ struct request_queue {
 	int			nr_rqs[2];	/* # allocated [a]sync rqs */
 	int			nr_rqs_elvpriv;	/* # allocated rqs w/ elvpriv */
 
+	struct blk_queue_stats	*stats;
 	struct rq_wb		*rq_wb;
 
 	/*
@@ -505,8 +509,6 @@ struct request_queue {
 	unsigned int		nr_sorted;
 	unsigned int		in_flight[2];
 
-	struct blk_rq_stat	rq_stats[2];
-
 	/*
 	 * Number of active block driver functions for which blk_drain_queue()
 	 * must wait. Must be incremented around functions that unlock the
@@ -516,6 +518,10 @@ struct request_queue {
 
 	unsigned int		rq_timeout;
 	int			poll_nsec;
+
+	struct blk_stat_callback	*poll_cb;
+	struct blk_rq_stat	poll_stat[BLK_MQ_POLL_STATS_BKTS];
+
 	struct timer_list	timeout;
 	struct work_struct	timeout_work;
 	struct list_head	timeout_list;
@@ -610,6 +616,8 @@ struct request_queue {
 #define QUEUE_FLAG_FLUSH_NQ    25	/* flush not queueuable */
 #define QUEUE_FLAG_DAX         26	/* device supports DAX */
 #define QUEUE_FLAG_STATS       27	/* track rq completion times */
+#define QUEUE_FLAG_POLL_STATS  28	/* collecting stats for hybrid polling */
+#define QUEUE_FLAG_REGISTERED  29	/* queue has been registered to a disk */
 
 #define QUEUE_FLAG_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
 				 (1 << QUEUE_FLAG_STACKABLE)	|	\
@@ -918,6 +926,7 @@ extern int blk_register_queue(struct gendisk *disk);
 extern void blk_unregister_queue(struct gendisk *disk);
 extern blk_qc_t generic_make_request(struct bio *bio);
 extern void blk_rq_init(struct request_queue *q, struct request *rq);
+extern void blk_init_request_from_bio(struct request *req, struct bio *bio);
 extern void blk_put_request(struct request *);
 extern void __blk_put_request(struct request_queue *, struct request *);
 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
@@ -963,7 +972,7 @@ extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, uns
 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
 			       struct rq_map_data *, const struct iov_iter *,
 			       gfp_t);
-extern int blk_execute_rq(struct request_queue *, struct gendisk *,
+extern void 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 *);
@@ -1081,20 +1090,6 @@ static inline unsigned int blk_rq_count_bios(struct request *rq)
 }
 
 /*
- * blk_rq_set_prio - associate a request with prio from ioc
- * @rq: request of interest
- * @ioc: target iocontext
- *
- * Assocate request prio with ioc prio so request based drivers
- * can leverage priority information.
- */
-static inline void blk_rq_set_prio(struct request *rq, struct io_context *ioc)
-{
-	if (ioc)
-		rq->ioprio = ioc->ioprio;
-}
-
-/*
  * Request issue related functions.
  */
 extern struct request *blk_peek_request(struct request_queue *q);
@@ -1120,13 +1115,10 @@ extern void blk_finish_request(struct request *rq, int error);
 extern bool blk_end_request(struct request *rq, int error,
 			    unsigned int nr_bytes);
 extern void blk_end_request_all(struct request *rq, int error);
-extern bool blk_end_request_cur(struct request *rq, int error);
-extern bool blk_end_request_err(struct request *rq, int error);
 extern bool __blk_end_request(struct request *rq, int error,
 			      unsigned int nr_bytes);
 extern void __blk_end_request_all(struct request *rq, int error);
 extern bool __blk_end_request_cur(struct request *rq, int error);
-extern bool __blk_end_request_err(struct request *rq, int error);
 
 extern void blk_complete_request(struct request *);
 extern void __blk_complete_request(struct request *);
@@ -1329,23 +1321,27 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
 	return bqt->tag_index[tag];
 }
 
+extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
+extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
+		sector_t nr_sects, gfp_t gfp_mask, struct page *page);
 
 #define BLKDEV_DISCARD_SECURE	(1 << 0)	/* issue a secure erase */
-#define BLKDEV_DISCARD_ZERO	(1 << 1)	/* must reliably zero data */
 
-extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
 		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
 		sector_t nr_sects, gfp_t gfp_mask, int flags,
 		struct bio **biop);
-extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
-		sector_t nr_sects, gfp_t gfp_mask, struct page *page);
+
+#define BLKDEV_ZERO_NOUNMAP	(1 << 0)  /* do not free blocks */
+#define BLKDEV_ZERO_NOFALLBACK	(1 << 1)  /* don't write explicit zeroes */
+
 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
 		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
-		bool discard);
+		unsigned flags);
 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
-		sector_t nr_sects, gfp_t gfp_mask, bool discard);
+		sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
+
 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
 		sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
 {
@@ -1359,7 +1355,7 @@ static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
 	return blkdev_issue_zeroout(sb->s_bdev,
 				    block << (sb->s_blocksize_bits - 9),
 				    nr_blocks << (sb->s_blocksize_bits - 9),
-				    gfp_mask, true);
+				    gfp_mask, 0);
 }
 
 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
@@ -1529,19 +1525,6 @@ static inline int bdev_discard_alignment(struct block_device *bdev)
 	return q->limits.discard_alignment;
 }
 
-static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
-{
-	if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
-		return 1;
-
-	return 0;
-}
-
-static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
-{
-	return queue_discard_zeroes_data(bdev_get_queue(bdev));
-}
-
 static inline unsigned int bdev_write_same(struct block_device *bdev)
 {
 	struct request_queue *q = bdev_get_queue(bdev);
@@ -1726,6 +1709,7 @@ int kblockd_schedule_work(struct work_struct *work);
 int kblockd_schedule_work_on(int cpu, struct work_struct *work);
 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
+int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
 
 #ifdef CONFIG_BLK_CGROUP
 /*
diff --git a/include/linux/coda_psdev.h b/include/linux/coda_psdev.h
index 5b8721efa948..31e4e1f1547c 100644
--- a/include/linux/coda_psdev.h
+++ b/include/linux/coda_psdev.h
@@ -15,7 +15,6 @@ struct venus_comm {
 	struct list_head    vc_processing;
 	int                 vc_inuse;
 	struct super_block *vc_sb;
-	struct backing_dev_info bdi;
 	struct mutex	    vc_mutex;
 };
 
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index a7e6903866fd..c7ea33e38fb9 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -255,6 +255,12 @@ struct dm_target {
 	unsigned num_write_same_bios;
 
 	/*
+	 * The number of WRITE ZEROES bios that will be submitted to the target.
+	 * The bio number can be accessed with dm_bio_get_target_bio_nr.
+	 */
+	unsigned num_write_zeroes_bios;
+
+	/*
 	 * The minimum number of extra bytes allocated in each io for the
 	 * target to use.
 	 */
@@ -290,11 +296,6 @@ struct dm_target {
 	 * on max_io_len boundary.
 	 */
 	bool split_discard_bios:1;
-
-	/*
-	 * Set if this target does not return zeroes on discarded blocks.
-	 */
-	bool discard_zeroes_data_unsupported:1;
 };
 
 /* Each target can link one of these into the table */
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 22d39e8d4de1..3a216318ae73 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -93,6 +93,8 @@ struct blk_mq_hw_ctx;
 struct elevator_mq_ops {
 	int (*init_sched)(struct request_queue *, struct elevator_type *);
 	void (*exit_sched)(struct elevator_queue *);
+	int (*init_hctx)(struct blk_mq_hw_ctx *, unsigned int);
+	void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int);
 
 	bool (*allow_merge)(struct request_queue *, struct request *, struct bio *);
 	bool (*bio_merge)(struct blk_mq_hw_ctx *, struct bio *);
@@ -104,7 +106,7 @@ struct elevator_mq_ops {
 	void (*insert_requests)(struct blk_mq_hw_ctx *, struct list_head *, bool);
 	struct request *(*dispatch_request)(struct blk_mq_hw_ctx *);
 	bool (*has_work)(struct blk_mq_hw_ctx *);
-	void (*completed_request)(struct blk_mq_hw_ctx *, struct request *);
+	void (*completed_request)(struct request *);
 	void (*started_request)(struct request *);
 	void (*requeue_request)(struct request *);
 	struct request *(*former_request)(struct request_queue *, struct request *);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7251f7bb45e8..30e5c14bd743 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2121,6 +2121,9 @@ extern int vfs_ustat(dev_t, struct kstatfs *);
 extern int freeze_super(struct super_block *super);
 extern int thaw_super(struct super_block *super);
 extern bool our_mnt(struct vfsmount *mnt);
+extern __printf(2, 3)
+int super_setup_bdi_name(struct super_block *sb, char *fmt, ...);
+extern int super_setup_bdi(struct super_block *sb);
 
 extern int current_umask(void);
 
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 76f39754e7b0..acff9437e5c3 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -159,11 +159,11 @@ struct badblocks;
 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 
 struct blk_integrity {
-	struct blk_integrity_profile	*profile;
-	unsigned char			flags;
-	unsigned char			tuple_size;
-	unsigned char			interval_exp;
-	unsigned char			tag_size;
+	const struct blk_integrity_profile	*profile;
+	unsigned char				flags;
+	unsigned char				tuple_size;
+	unsigned char				interval_exp;
+	unsigned char				tag_size;
 };
 
 #endif	/* CONFIG_BLK_DEV_INTEGRITY */
@@ -722,11 +722,9 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 extern void blk_integrity_add(struct gendisk *);
 extern void blk_integrity_del(struct gendisk *);
-extern void blk_integrity_revalidate(struct gendisk *);
 #else	/* CONFIG_BLK_DEV_INTEGRITY */
 static inline void blk_integrity_add(struct gendisk *disk) { }
 static inline void blk_integrity_del(struct gendisk *disk) { }
-static inline void blk_integrity_revalidate(struct gendisk *disk) { }
 #endif	/* CONFIG_BLK_DEV_INTEGRITY */
 
 #else /* CONFIG_BLOCK */
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 2f51c1724b5a..6980ca322074 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -88,7 +88,7 @@ static inline bool ata_pm_request(struct request *rq)
 		 ide_req(rq)->type == ATA_PRIV_PM_RESUME);
 }
 
-/* Error codes returned in rq->errors to the higher part of the driver. */
+/* Error codes returned in result to the higher part of the driver. */
 enum {
 	IDE_DRV_ERROR_GENERAL	= 101,
 	IDE_DRV_ERROR_FILEMARK	= 102,
diff --git a/include/linux/inet.h b/include/linux/inet.h
index 4cca05c9678e..636ebe87e6f8 100644
--- a/include/linux/inet.h
+++ b/include/linux/inet.h
@@ -43,6 +43,8 @@
 #define _LINUX_INET_H
 
 #include <linux/types.h>
+#include <net/net_namespace.h>
+#include <linux/socket.h>
 
 /*
  * These mimic similar macros defined in user-space for inet_ntop(3).
@@ -54,4 +56,8 @@
 extern __be32 in_aton(const char *str);
 extern int in4_pton(const char *src, int srclen, u8 *dst, int delim, const char **end);
 extern int in6_pton(const char *src, int srclen, u8 *dst, int delim, const char **end);
+
+extern int inet_pton_with_scope(struct net *net, unsigned short af,
+		const char *src, const char *port, struct sockaddr_storage *addr);
+
 #endif	/* _LINUX_INET_H */
diff --git a/include/linux/kobject.h b/include/linux/kobject.h
index e6284591599e..ca85cb80e99a 100644
--- a/include/linux/kobject.h
+++ b/include/linux/kobject.h
@@ -108,6 +108,8 @@ extern int __must_check kobject_rename(struct kobject *, const char *new_name);
 extern int __must_check kobject_move(struct kobject *, struct kobject *);
 
 extern struct kobject *kobject_get(struct kobject *kobj);
+extern struct kobject * __must_check kobject_get_unless_zero(
+						struct kobject *kobj);
 extern void kobject_put(struct kobject *kobj);
 
 extern const void *kobject_namespace(struct kobject *kobj);
diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
index ca45e4a088a9..7dfa56ebbc6d 100644
--- a/include/linux/lightnvm.h
+++ b/include/linux/lightnvm.h
@@ -56,7 +56,6 @@ typedef int (nvm_get_l2p_tbl_fn)(struct nvm_dev *, u64, u32,
 typedef int (nvm_op_bb_tbl_fn)(struct nvm_dev *, struct ppa_addr, u8 *);
 typedef int (nvm_op_set_bb_fn)(struct nvm_dev *, struct ppa_addr *, int, int);
 typedef int (nvm_submit_io_fn)(struct nvm_dev *, struct nvm_rq *);
-typedef int (nvm_erase_blk_fn)(struct nvm_dev *, struct nvm_rq *);
 typedef void *(nvm_create_dma_pool_fn)(struct nvm_dev *, char *);
 typedef void (nvm_destroy_dma_pool_fn)(void *);
 typedef void *(nvm_dev_dma_alloc_fn)(struct nvm_dev *, void *, gfp_t,
@@ -70,7 +69,6 @@ struct nvm_dev_ops {
 	nvm_op_set_bb_fn	*set_bb_tbl;
 
 	nvm_submit_io_fn	*submit_io;
-	nvm_erase_blk_fn	*erase_block;
 
 	nvm_create_dma_pool_fn	*create_dma_pool;
 	nvm_destroy_dma_pool_fn	*destroy_dma_pool;
@@ -125,7 +123,7 @@ enum {
 	/* NAND Access Modes */
 	NVM_IO_SUSPEND		= 0x80,
 	NVM_IO_SLC_MODE		= 0x100,
-	NVM_IO_SCRAMBLE_DISABLE	= 0x200,
+	NVM_IO_SCRAMBLE_ENABLE	= 0x200,
 
 	/* Block Types */
 	NVM_BLK_T_FREE		= 0x0,
@@ -438,7 +436,8 @@ static inline int ppa_cmp_blk(struct ppa_addr ppa1, struct ppa_addr ppa2)
 
 typedef blk_qc_t (nvm_tgt_make_rq_fn)(struct request_queue *, struct bio *);
 typedef sector_t (nvm_tgt_capacity_fn)(void *);
-typedef void *(nvm_tgt_init_fn)(struct nvm_tgt_dev *, struct gendisk *);
+typedef void *(nvm_tgt_init_fn)(struct nvm_tgt_dev *, struct gendisk *,
+				int flags);
 typedef void (nvm_tgt_exit_fn)(void *);
 typedef int (nvm_tgt_sysfs_init_fn)(struct gendisk *);
 typedef void (nvm_tgt_sysfs_exit_fn)(struct gendisk *);
@@ -479,10 +478,10 @@ extern int nvm_set_tgt_bb_tbl(struct nvm_tgt_dev *, struct ppa_addr *,
 			      int, int);
 extern int nvm_max_phys_sects(struct nvm_tgt_dev *);
 extern int nvm_submit_io(struct nvm_tgt_dev *, struct nvm_rq *);
-extern int nvm_set_rqd_ppalist(struct nvm_dev *, struct nvm_rq *,
+extern int nvm_erase_sync(struct nvm_tgt_dev *, struct ppa_addr *, int);
+extern int nvm_set_rqd_ppalist(struct nvm_tgt_dev *, struct nvm_rq *,
 					const struct ppa_addr *, int, int);
-extern void nvm_free_rqd_ppalist(struct nvm_dev *, struct nvm_rq *);
-extern int nvm_erase_blk(struct nvm_tgt_dev *, struct ppa_addr *, int);
+extern void nvm_free_rqd_ppalist(struct nvm_tgt_dev *, struct nvm_rq *);
 extern int nvm_get_l2p_tbl(struct nvm_tgt_dev *, u64, u32, nvm_l2p_update_fn *,
 			   void *);
 extern int nvm_get_area(struct nvm_tgt_dev *, sector_t *, sector_t);
diff --git a/include/linux/mg_disk.h b/include/linux/mg_disk.h
deleted file mode 100644
index e11f4d9f1c2e..000000000000
--- a/include/linux/mg_disk.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- *  include/linux/mg_disk.c
- *
- *  Private data for mflash platform driver
- *
- * (c) 2008 mGine Co.,LTD
- * (c) 2008 unsik Kim <donari75@gmail.com>
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License version 2 as
- *  published by the Free Software Foundation.
- */
-
-#ifndef __MG_DISK_H__
-#define __MG_DISK_H__
-
-/* name for platform device */
-#define MG_DEV_NAME "mg_disk"
-
-/* names of GPIO resource */
-#define MG_RST_PIN	"mg_rst"
-/* except MG_BOOT_DEV, reset-out pin should be assigned */
-#define MG_RSTOUT_PIN	"mg_rstout"
-
-/* device attribution */
-/* use mflash as boot device */
-#define MG_BOOT_DEV		(1 << 0)
-/* use mflash as storage device */
-#define MG_STORAGE_DEV		(1 << 1)
-/* same as MG_STORAGE_DEV, but bootloader already done reset sequence */
-#define MG_STORAGE_DEV_SKIP_RST	(1 << 2)
-
-/* private driver data */
-struct mg_drv_data {
-	/* disk resource */
-	u32 use_polling;
-
-	/* device attribution */
-	u32 dev_attr;
-
-	/* internally used */
-	void *host;
-};
-
-#endif
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index eebdc63cf6af..79b176eca04a 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -334,11 +334,6 @@ struct mtd_info {
 	int (*_get_device) (struct mtd_info *mtd);
 	void (*_put_device) (struct mtd_info *mtd);
 
-	/* Backing device capabilities for this device
-	 * - provides mmap capabilities
-	 */
-	struct backing_dev_info *backing_dev_info;
-
 	struct notifier_block reboot_notifier;  /* default mode before reboot */
 
 	/* ECC status information */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index b34097c67848..e1502c55741e 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -133,7 +133,6 @@ struct nfs_server {
 	struct rpc_clnt *	client_acl;	/* ACL RPC client handle */
 	struct nlm_host		*nlm_host;	/* NLM client handle */
 	struct nfs_iostats __percpu *io_stats;	/* I/O statistics */
-	struct backing_dev_info	backing_dev_info;
 	atomic_long_t		writeback;	/* number of writeback pages */
 	int			flags;		/* various flags */
 	unsigned int		caps;		/* server capabilities */
diff --git a/include/linux/nvme-fc-driver.h b/include/linux/nvme-fc-driver.h
index f21471f7ee40..0db37158a61d 100644
--- a/include/linux/nvme-fc-driver.h
+++ b/include/linux/nvme-fc-driver.h
@@ -137,9 +137,9 @@ enum nvmefc_fcp_datadir {
  *             transferred. Should equal payload_length on success.
  * @rcv_rsplen: length, in bytes, of the FCP RSP IU received.
  * @status:    Completion status of the FCP operation. must be 0 upon success,
- *             NVME_SC_FC_xxx value upon failure. Note: this is NOT a
- *             reflection of the NVME CQE completion status. Only the status
- *             of the FCP operation at the NVME-FC level.
+ *             negative errno value upon failure (ex: -EIO). Note: this is
+ *             NOT a reflection of the NVME CQE completion status. Only the
+ *             status of the FCP operation at the NVME-FC level.
  */
 struct nvmefc_fcp_req {
 	void			*cmdaddr;
@@ -533,9 +533,6 @@ enum {
 					 * rsp as well
 					 */
 	NVMET_FCOP_RSP		= 4,	/* send rsp frame */
-	NVMET_FCOP_ABORT	= 5,	/* abort exchange via ABTS */
-	NVMET_FCOP_BA_ACC	= 6,	/* send BA_ACC */
-	NVMET_FCOP_BA_RJT	= 7,	/* send BA_RJT */
 };
 
 /**
@@ -572,8 +569,6 @@ enum {
  *     upon compeletion of the operation.  The nvmet-fc layer will also set a
  *     private pointer for its own use in the done routine.
  *
- * Note: the LLDD must never fail a NVMET_FCOP_ABORT request !!
- *
  * Values set by the NVMET-FC layer prior to calling the LLDD fcp_op
  * entrypoint.
  * @op:       Indicates the FCP IU operation to perform (see NVMET_FCOP_xxx)
@@ -655,6 +650,22 @@ enum {
 		 * on. The transport should pick a cpu to schedule the work
 		 * on.
 		 */
+	NVMET_FCTGTFEAT_CMD_IN_ISR = (1 << 2),
+		/* Bit 2: When 0, the LLDD is calling the cmd rcv handler
+		 * in a non-isr context, allowing the transport to finish
+		 * op completion in the calling context. When 1, the LLDD
+		 * is calling the cmd rcv handler in an ISR context,
+		 * requiring the transport to transition to a workqueue
+		 * for op completion.
+		 */
+	NVMET_FCTGTFEAT_OPDONE_IN_ISR = (1 << 3),
+		/* Bit 3: When 0, the LLDD is calling the op done handler
+		 * in a non-isr context, allowing the transport to finish
+		 * op completion in the calling context. When 1, the LLDD
+		 * is calling the op done handler in an ISR context,
+		 * requiring the transport to transition to a workqueue
+		 * for op completion.
+		 */
 };
 
 
@@ -725,12 +736,12 @@ struct nvmet_fc_target_port {
  *       be freed/released.
  *       Entrypoint is Mandatory.
  *
- * @fcp_op:  Called to perform a data transfer, transmit a response, or
- *       abort an FCP opertion. The nvmefc_tgt_fcp_req structure is the same
- *       LLDD-supplied exchange structure specified in the
- *       nvmet_fc_rcv_fcp_req() call made when the FCP CMD IU was received.
- *       The op field in the structure shall indicate the operation for
- *       the LLDD to perform relative to the io.
+ * @fcp_op:  Called to perform a data transfer or transmit a response.
+ *       The nvmefc_tgt_fcp_req structure is the same LLDD-supplied
+ *       exchange structure specified in the nvmet_fc_rcv_fcp_req() call
+ *       made when the FCP CMD IU was received. The op field in the
+ *       structure shall indicate the operation for the LLDD to perform
+ *       relative to the io.
  *         NVMET_FCOP_READDATA operation: the LLDD is to send the
  *           payload data (described by sglist) to the host in 1 or
  *           more FC sequences (preferrably 1).  Note: the fc-nvme layer
@@ -752,29 +763,31 @@ struct nvmet_fc_target_port {
  *           successfully, the LLDD is to update the nvmefc_tgt_fcp_req
  *           transferred_length field and may subsequently transmit the
  *           FCP_RSP iu payload (described by rspbuf, rspdma, rsplen).
- *           The LLDD is to await FCP_CONF reception to confirm the RSP
- *           reception by the host. The LLDD may retramsit the FCP_RSP iu
- *           if necessary per FC-NVME. Upon reception of FCP_CONF, or upon
- *           FCP_CONF failure, the LLDD is to set the nvmefc_tgt_fcp_req
- *           fcp_error field and consider the operation complete..
+ *           If FCP_CONF is supported, the LLDD is to await FCP_CONF
+ *           reception to confirm the RSP reception by the host. The LLDD
+ *           may retramsit the FCP_RSP iu if necessary per FC-NVME. Upon
+ *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
+ *           or upon success/failure of FCP_CONF if it is supported, the
+ *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
+ *           consider the operation complete.
  *         NVMET_FCOP_RSP: the LLDD is to transmit the FCP_RSP iu payload
- *           (described by rspbuf, rspdma, rsplen).  The LLDD is to await
- *           FCP_CONF reception to confirm the RSP reception by the host.
- *           The LLDD may retramsit the FCP_RSP iu if necessary per FC-NVME.
- *           Upon reception of FCP_CONF, or upon FCP_CONF failure, the
+ *           (described by rspbuf, rspdma, rsplen). If FCP_CONF is
+ *           supported, the LLDD is to await FCP_CONF reception to confirm
+ *           the RSP reception by the host. The LLDD may retramsit the
+ *           FCP_RSP iu if FCP_CONF is not received per FC-NVME. Upon
+ *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
+ *           or upon success/failure of FCP_CONF if it is supported, the
  *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
- *           consider the operation complete..
- *         NVMET_FCOP_ABORT: the LLDD is to terminate the exchange
- *           corresponding to the fcp operation. The LLDD shall send
- *           ABTS and follow FC exchange abort-multi rules, including
- *           ABTS retries and possible logout.
+ *           consider the operation complete.
  *       Upon completing the indicated operation, the LLDD is to set the
  *       status fields for the operation (tranferred_length and fcp_error
- *       status) in the request, then all the "done" routine
- *       indicated in the fcp request.  Upon return from the "done"
- *       routine for either a NVMET_FCOP_RSP or NVMET_FCOP_ABORT operation
- *       the fc-nvme layer will not longer reference the fcp request,
- *       allowing the LLDD to free/release the fcp request.
+ *       status) in the request, then call the "done" routine
+ *       indicated in the fcp request. After the operation completes,
+ *       regardless of whether the FCP_RSP iu was successfully transmit,
+ *       the LLDD-supplied exchange structure must remain valid until the
+ *       transport calls the fcp_req_release() callback to return ownership
+ *       of the exchange structure back to the LLDD so that it may be used
+ *       for another fcp command.
  *       Note: when calling the done routine for READDATA or WRITEDATA
  *       operations, the fc-nvme layer may immediate convert, in the same
  *       thread and before returning to the LLDD, the fcp operation to
@@ -786,6 +799,22 @@ struct nvmet_fc_target_port {
  *       Returns 0 on success, -<errno> on failure (Ex: -EIO)
  *       Entrypoint is Mandatory.
  *
+ * @fcp_abort:  Called by the transport to abort an active command.
+ *       The command may be in-between operations (nothing active in LLDD)
+ *       or may have an active WRITEDATA operation pending. The LLDD is to
+ *       initiate the ABTS process for the command and return from the
+ *       callback. The ABTS does not need to be complete on the command.
+ *       The fcp_abort callback inherently cannot fail. After the
+ *       fcp_abort() callback completes, the transport will wait for any
+ *       outstanding operation (if there was one) to complete, then will
+ *       call the fcp_req_release() callback to return the command's
+ *       exchange context back to the LLDD.
+ *
+ * @fcp_req_release:  Called by the transport to return a nvmefc_tgt_fcp_req
+ *       to the LLDD after all operations on the fcp operation are complete.
+ *       This may be due to the command completing or upon completion of
+ *       abort cleanup.
+ *
  * @max_hw_queues:  indicates the maximum number of hw queues the LLDD
  *       supports for cpu affinitization.
  *       Value is Mandatory. Must be at least 1.
@@ -820,7 +849,11 @@ struct nvmet_fc_target_template {
 	int (*xmt_ls_rsp)(struct nvmet_fc_target_port *tgtport,
 				struct nvmefc_tgt_ls_req *tls_req);
 	int (*fcp_op)(struct nvmet_fc_target_port *tgtport,
-				struct nvmefc_tgt_fcp_req *);
+				struct nvmefc_tgt_fcp_req *fcpreq);
+	void (*fcp_abort)(struct nvmet_fc_target_port *tgtport,
+				struct nvmefc_tgt_fcp_req *fcpreq);
+	void (*fcp_req_release)(struct nvmet_fc_target_port *tgtport,
+				struct nvmefc_tgt_fcp_req *fcpreq);
 
 	u32	max_hw_queues;
 	u16	max_sgl_segments;
@@ -848,4 +881,7 @@ int nvmet_fc_rcv_fcp_req(struct nvmet_fc_target_port *tgtport,
 			struct nvmefc_tgt_fcp_req *fcpreq,
 			void *cmdiubuf, u32 cmdiubuf_len);
 
+void nvmet_fc_rcv_fcp_abort(struct nvmet_fc_target_port *tgtport,
+			struct nvmefc_tgt_fcp_req *fcpreq);
+
 #endif /* _NVME_FC_DRIVER_H */
diff --git a/include/linux/nvme-fc.h b/include/linux/nvme-fc.h
index 4b45226bd604..e997c4a49a88 100644
--- a/include/linux/nvme-fc.h
+++ b/include/linux/nvme-fc.h
@@ -16,8 +16,7 @@
  */
 
 /*
- * This file contains definitions relative to FC-NVME r1.11 and a few
- * newer items
+ * This file contains definitions relative to FC-NVME r1.14 (16-020vB).
  */
 
 #ifndef _NVME_FC_H
@@ -47,8 +46,15 @@ struct nvme_fc_cmd_iu {
 
 #define NVME_FC_SIZEOF_ZEROS_RSP	12
 
+enum {
+	FCNVME_SC_SUCCESS		= 0,
+	FCNVME_SC_INVALID_FIELD		= 1,
+	FCNVME_SC_INVALID_CONNID	= 2,
+};
+
 struct nvme_fc_ersp_iu {
-	__u8			rsvd0[2];
+	__u8			status_code;
+	__u8			rsvd1;
 	__be16			iu_len;
 	__be32			rsn;
 	__be32			xfrd_len;
@@ -58,7 +64,7 @@ struct nvme_fc_ersp_iu {
 };
 
 
-/* FC-NVME r1.03/16-119v0 NVME Link Services */
+/* FC-NVME Link Services */
 enum {
 	FCNVME_LS_RSVD			= 0,
 	FCNVME_LS_RJT			= 1,
@@ -68,7 +74,7 @@ enum {
 	FCNVME_LS_DISCONNECT		= 5,
 };
 
-/* FC-NVME r1.03/16-119v0 NVME Link Service Descriptors */
+/* FC-NVME Link Service Descriptors */
 enum {
 	FCNVME_LSDESC_RSVD		= 0x0,
 	FCNVME_LSDESC_RQST		= 0x1,
@@ -92,7 +98,6 @@ static inline __be32 fcnvme_lsdesc_len(size_t sz)
 	return cpu_to_be32(sz - (2 * sizeof(u32)));
 }
 
-
 struct fcnvme_ls_rqst_w0 {
 	u8	ls_cmd;			/* FCNVME_LS_xxx */
 	u8	zeros[3];
@@ -106,8 +111,53 @@ struct fcnvme_lsdesc_rqst {
 	__be32	rsvd12;
 };
 
+/* FC-NVME LS RJT reason_code values */
+enum fcnvme_ls_rjt_reason {
+	FCNVME_RJT_RC_NONE		= 0,
+	/* no reason - not to be sent */
+
+	FCNVME_RJT_RC_INVAL		= 0x01,
+	/* invalid NVMe_LS command code */
+
+	FCNVME_RJT_RC_LOGIC		= 0x03,
+	/* logical error */
+
+	FCNVME_RJT_RC_UNAB		= 0x09,
+	/* unable to perform command request */
+
+	FCNVME_RJT_RC_UNSUP		= 0x0b,
+	/* command not supported */
+
+	FCNVME_RJT_RC_INPROG		= 0x0e,
+	/* command already in progress */
 
+	FCNVME_RJT_RC_INV_ASSOC		= 0x40,
+	/* Invalid Association ID*/
 
+	FCNVME_RJT_RC_INV_CONN		= 0x41,
+	/* Invalid Connection ID*/
+
+	FCNVME_RJT_RC_VENDOR		= 0xff,
+	/* vendor specific error */
+};
+
+/* FC-NVME LS RJT reason_explanation values */
+enum fcnvme_ls_rjt_explan {
+	FCNVME_RJT_EXP_NONE		= 0x00,
+	/* No additional explanation */
+
+	FCNVME_RJT_EXP_OXID_RXID	= 0x17,
+	/* invalid OX_ID-RX_ID combination */
+
+	FCNVME_RJT_EXP_INSUF_RES	= 0x29,
+	/* insufficient resources */
+
+	FCNVME_RJT_EXP_UNAB_DATA	= 0x2a,
+	/* unable to supply requested data */
+
+	FCNVME_RJT_EXP_INV_LEN		= 0x2d,
+	/* Invalid payload length */
+};
 
 /* FCNVME_LSDESC_RJT */
 struct fcnvme_lsdesc_rjt {
@@ -119,15 +169,15 @@ struct fcnvme_lsdesc_rjt {
 	 * Reject reason and explanaction codes are generic
 	 * to ELs's from LS-3.
 	 */
-	u8	reason_code;
-	u8	reason_explanation;
+	u8	reason_code;		/* fcnvme_ls_rjt_reason */
+	u8	reason_explanation;	/* fcnvme_ls_rjt_explan */
 
 	u8	vendor;
 	__be32	rsvd12;
 };
 
 
-#define FCNVME_ASSOC_HOSTID_LEN		64
+#define FCNVME_ASSOC_HOSTID_LEN		16
 #define FCNVME_ASSOC_HOSTNQN_LEN	256
 #define FCNVME_ASSOC_SUBNQN_LEN		256
 
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 9061780b141f..b625bacf37ef 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -245,6 +245,7 @@ enum {
 	NVME_CTRL_ONCS_WRITE_ZEROES		= 1 << 3,
 	NVME_CTRL_VWC_PRESENT			= 1 << 0,
 	NVME_CTRL_OACS_SEC_SUPP                 = 1 << 0,
+	NVME_CTRL_OACS_DBBUF_SUPP		= 1 << 7,
 };
 
 struct nvme_lbaf {
@@ -603,6 +604,7 @@ enum nvme_admin_opcode {
 	nvme_admin_download_fw		= 0x11,
 	nvme_admin_ns_attach		= 0x15,
 	nvme_admin_keep_alive		= 0x18,
+	nvme_admin_dbbuf		= 0x7C,
 	nvme_admin_format_nvm		= 0x80,
 	nvme_admin_security_send	= 0x81,
 	nvme_admin_security_recv	= 0x82,
@@ -874,6 +876,16 @@ struct nvmf_property_get_command {
 	__u8		resv4[16];
 };
 
+struct nvme_dbbuf {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__u32			rsvd1[5];
+	__le64			prp1;
+	__le64			prp2;
+	__u32			rsvd12[6];
+};
+
 struct nvme_command {
 	union {
 		struct nvme_common_command common;
@@ -893,6 +905,7 @@ struct nvme_command {
 		struct nvmf_connect_command connect;
 		struct nvmf_property_set_command prop_set;
 		struct nvmf_property_get_command prop_get;
+		struct nvme_dbbuf dbbuf;
 	};
 };
 
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index d4e0a204c118..a1904aadbc45 100644
--- a/include/linux/sbitmap.h
+++ b/include/linux/sbitmap.h
@@ -176,6 +176,25 @@ void sbitmap_resize(struct sbitmap *sb, unsigned int depth);
 int sbitmap_get(struct sbitmap *sb, unsigned int alloc_hint, bool round_robin);
 
 /**
+ * sbitmap_get_shallow() - Try to allocate a free bit from a &struct sbitmap,
+ * limiting the depth used from each word.
+ * @sb: Bitmap to allocate from.
+ * @alloc_hint: Hint for where to start searching for a free bit.
+ * @shallow_depth: The maximum number of bits to allocate from a single word.
+ *
+ * This rather specific operation allows for having multiple users with
+ * different allocation limits. E.g., there can be a high-priority class that
+ * uses sbitmap_get() and a low-priority class that uses sbitmap_get_shallow()
+ * with a @shallow_depth of (1 << (@sb->shift - 1)). Then, the low-priority
+ * class can only allocate half of the total bits in the bitmap, preventing it
+ * from starving out the high-priority class.
+ *
+ * Return: Non-negative allocated bit number if successful, -1 otherwise.
+ */
+int sbitmap_get_shallow(struct sbitmap *sb, unsigned int alloc_hint,
+			unsigned long shallow_depth);
+
+/**
  * sbitmap_any_bit_set() - Check for a set bit in a &struct sbitmap.
  * @sb: Bitmap to check.
  *
@@ -326,6 +345,19 @@ void sbitmap_queue_resize(struct sbitmap_queue *sbq, unsigned int depth);
 int __sbitmap_queue_get(struct sbitmap_queue *sbq);
 
 /**
+ * __sbitmap_queue_get_shallow() - Try to allocate a free bit from a &struct
+ * sbitmap_queue, limiting the depth used from each word, with preemption
+ * already disabled.
+ * @sbq: Bitmap queue to allocate from.
+ * @shallow_depth: The maximum number of bits to allocate from a single word.
+ * See sbitmap_get_shallow().
+ *
+ * Return: Non-negative allocated bit number if successful, -1 otherwise.
+ */
+int __sbitmap_queue_get_shallow(struct sbitmap_queue *sbq,
+				unsigned int shallow_depth);
+
+/**
  * sbitmap_queue_get() - Try to allocate a free bit from a &struct
  * sbitmap_queue.
  * @sbq: Bitmap queue to allocate from.
@@ -346,6 +378,29 @@ static inline int sbitmap_queue_get(struct sbitmap_queue *sbq,
 }
 
 /**
+ * sbitmap_queue_get_shallow() - Try to allocate a free bit from a &struct
+ * sbitmap_queue, limiting the depth used from each word.
+ * @sbq: Bitmap queue to allocate from.
+ * @cpu: Output parameter; will contain the CPU we ran on (e.g., to be passed to
+ *       sbitmap_queue_clear()).
+ * @shallow_depth: The maximum number of bits to allocate from a single word.
+ * See sbitmap_get_shallow().
+ *
+ * Return: Non-negative allocated bit number if successful, -1 otherwise.
+ */
+static inline int sbitmap_queue_get_shallow(struct sbitmap_queue *sbq,
+					    unsigned int *cpu,
+					    unsigned int shallow_depth)
+{
+	int nr;
+
+	*cpu = get_cpu();
+	nr = __sbitmap_queue_get_shallow(sbq, shallow_depth);
+	put_cpu();
+	return nr;
+}
+
+/**
  * sbitmap_queue_clear() - Free an allocated bit and wake up waiters on a
  * &struct sbitmap_queue.
  * @sbq: Bitmap to free from.
diff --git a/include/linux/t10-pi.h b/include/linux/t10-pi.h
index 9fba9dd33544..9375d23a24e7 100644
--- a/include/linux/t10-pi.h
+++ b/include/linux/t10-pi.h
@@ -34,9 +34,9 @@ struct t10_pi_tuple {
 };
 
 
-extern struct blk_integrity_profile t10_pi_type1_crc;
-extern struct blk_integrity_profile t10_pi_type1_ip;
-extern struct blk_integrity_profile t10_pi_type3_crc;
-extern struct blk_integrity_profile t10_pi_type3_ip;
+extern const struct blk_integrity_profile t10_pi_type1_crc;
+extern const struct blk_integrity_profile t10_pi_type1_ip;
+extern const struct blk_integrity_profile t10_pi_type3_crc;
+extern const struct blk_integrity_profile t10_pi_type3_ip;
 
 #endif
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index a3c0cbd7c888..d5815794416c 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -237,6 +237,7 @@ static inline void inode_attach_wb(struct inode *inode, struct page *page)
 static inline void inode_detach_wb(struct inode *inode)
 {
 	if (inode->i_wb) {
+		WARN_ON_ONCE(!(inode->i_state & I_CLEAR));
 		wb_put(inode->i_wb);
 		inode->i_wb = NULL;
 	}
diff --git a/include/scsi/scsi_request.h b/include/scsi/scsi_request.h
index ba0aeb980f7e..f0c76f9dc285 100644
--- a/include/scsi/scsi_request.h
+++ b/include/scsi/scsi_request.h
@@ -9,8 +9,10 @@ struct scsi_request {
 	unsigned char	__cmd[BLK_MAX_CDB];
 	unsigned char	*cmd;
 	unsigned short	cmd_len;
+	int		result;
 	unsigned int	sense_len;
 	unsigned int	resid_len;	/* residual count */
+	int		retries;
 	void		*sense;
 };
 
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index a88ed13446ff..d0dbe60d8a6d 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -61,7 +61,16 @@ DEFINE_EVENT(block_buffer, block_dirty_buffer,
 	TP_ARGS(bh)
 );
 
-DECLARE_EVENT_CLASS(block_rq_with_error,
+/**
+ * block_rq_requeue - place block IO request back on a queue
+ * @q: queue holding operation
+ * @rq: block IO operation request
+ *
+ * The block operation request @rq is being placed back into queue
+ * @q.  For some reason the request was not completed and needs to be
+ * put back in the queue.
+ */
+TRACE_EVENT(block_rq_requeue,
 
 	TP_PROTO(struct request_queue *q, struct request *rq),
 
@@ -71,7 +80,6 @@ DECLARE_EVENT_CLASS(block_rq_with_error,
 		__field(  dev_t,	dev			)
 		__field(  sector_t,	sector			)
 		__field(  unsigned int,	nr_sector		)
-		__field(  int,		errors			)
 		__array(  char,		rwbs,	RWBS_LEN	)
 		__dynamic_array( char,	cmd,	1		)
 	),
@@ -80,7 +88,6 @@ DECLARE_EVENT_CLASS(block_rq_with_error,
 		__entry->dev	   = rq->rq_disk ? disk_devt(rq->rq_disk) : 0;
 		__entry->sector    = blk_rq_trace_sector(rq);
 		__entry->nr_sector = blk_rq_trace_nr_sectors(rq);
-		__entry->errors    = rq->errors;
 
 		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));
 		__get_str(cmd)[0] = '\0';
@@ -90,46 +97,13 @@ DECLARE_EVENT_CLASS(block_rq_with_error,
 		  MAJOR(__entry->dev), MINOR(__entry->dev),
 		  __entry->rwbs, __get_str(cmd),
 		  (unsigned long long)__entry->sector,
-		  __entry->nr_sector, __entry->errors)
-);
-
-/**
- * block_rq_abort - abort block operation request
- * @q: queue containing the block operation request
- * @rq: block IO operation request
- *
- * Called immediately after pending block IO operation request @rq in
- * queue @q is aborted. The fields in the operation request @rq
- * can be examined to determine which device and sectors the pending
- * operation would access.
- */
-DEFINE_EVENT(block_rq_with_error, block_rq_abort,
-
-	TP_PROTO(struct request_queue *q, struct request *rq),
-
-	TP_ARGS(q, rq)
-);
-
-/**
- * block_rq_requeue - place block IO request back on a queue
- * @q: queue holding operation
- * @rq: block IO operation request
- *
- * The block operation request @rq is being placed back into queue
- * @q.  For some reason the request was not completed and needs to be
- * put back in the queue.
- */
-DEFINE_EVENT(block_rq_with_error, block_rq_requeue,
-
-	TP_PROTO(struct request_queue *q, struct request *rq),
-
-	TP_ARGS(q, rq)
+		  __entry->nr_sector, 0)
 );
 
 /**
  * block_rq_complete - block IO operation completed by device driver
- * @q: queue containing the block operation request
  * @rq: block operations request
+ * @error: status code
  * @nr_bytes: number of completed bytes
  *
  * The block_rq_complete tracepoint event indicates that some portion
@@ -140,16 +114,15 @@ DEFINE_EVENT(block_rq_with_error, block_rq_requeue,
  */
 TRACE_EVENT(block_rq_complete,
 
-	TP_PROTO(struct request_queue *q, struct request *rq,
-		 unsigned int nr_bytes),
+	TP_PROTO(struct request *rq, int error, unsigned int nr_bytes),
 
-	TP_ARGS(q, rq, nr_bytes),
+	TP_ARGS(rq, error, nr_bytes),
 
 	TP_STRUCT__entry(
 		__field(  dev_t,	dev			)
 		__field(  sector_t,	sector			)
 		__field(  unsigned int,	nr_sector		)
-		__field(  int,		errors			)
+		__field(  int,		error			)
 		__array(  char,		rwbs,	RWBS_LEN	)
 		__dynamic_array( char,	cmd,	1		)
 	),
@@ -158,7 +131,7 @@ TRACE_EVENT(block_rq_complete,
 		__entry->dev	   = rq->rq_disk ? disk_devt(rq->rq_disk) : 0;
 		__entry->sector    = blk_rq_pos(rq);
 		__entry->nr_sector = nr_bytes >> 9;
-		__entry->errors    = rq->errors;
+		__entry->error     = error;
 
 		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, nr_bytes);
 		__get_str(cmd)[0] = '\0';
@@ -168,7 +141,7 @@ TRACE_EVENT(block_rq_complete,
 		  MAJOR(__entry->dev), MINOR(__entry->dev),
 		  __entry->rwbs, __get_str(cmd),
 		  (unsigned long long)__entry->sector,
-		  __entry->nr_sector, __entry->errors)
+		  __entry->nr_sector, __entry->error)
 );
 
 DECLARE_EVENT_CLASS(block_rq,
diff --git a/include/uapi/linux/lightnvm.h b/include/uapi/linux/lightnvm.h
index fd19f36b3129..c8aec4b9e73b 100644
--- a/include/uapi/linux/lightnvm.h
+++ b/include/uapi/linux/lightnvm.h
@@ -85,6 +85,10 @@ struct nvm_ioctl_create_conf {
 	};
 };
 
+enum {
+	NVM_TARGET_FACTORY = 1 << 0,	/* Init target in factory mode */
+};
+
 struct nvm_ioctl_create {
 	char dev[DISK_NAME_LEN];		/* open-channel SSD device */
 	char tgttype[NVM_TTYPE_NAME_MAX];	/* target type name */
diff --git a/include/uapi/linux/nbd-netlink.h b/include/uapi/linux/nbd-netlink.h
new file mode 100644
index 000000000000..6f7ca3d63a65
--- /dev/null
+++ b/include/uapi/linux/nbd-netlink.h
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2017 Facebook.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * 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 021110-1307, USA.
+ */
+#ifndef _UAPILINUX_NBD_NETLINK_H
+#define _UAPILINUX_NBD_NETLINK_H
+
+#define NBD_GENL_FAMILY_NAME		"nbd"
+#define NBD_GENL_VERSION		0x1
+#define NBD_GENL_MCAST_GROUP_NAME	"nbd_mc_group"
+
+/* Configuration policy attributes, used for CONNECT */
+enum {
+	NBD_ATTR_UNSPEC,
+	NBD_ATTR_INDEX,
+	NBD_ATTR_SIZE_BYTES,
+	NBD_ATTR_BLOCK_SIZE_BYTES,
+	NBD_ATTR_TIMEOUT,
+	NBD_ATTR_SERVER_FLAGS,
+	NBD_ATTR_CLIENT_FLAGS,
+	NBD_ATTR_SOCKETS,
+	NBD_ATTR_DEAD_CONN_TIMEOUT,
+	NBD_ATTR_DEVICE_LIST,
+	__NBD_ATTR_MAX,
+};
+#define NBD_ATTR_MAX (__NBD_ATTR_MAX - 1)
+
+/*
+ * This is the format for multiple devices with NBD_ATTR_DEVICE_LIST
+ *
+ * [NBD_ATTR_DEVICE_LIST]
+ *   [NBD_DEVICE_ITEM]
+ *     [NBD_DEVICE_INDEX]
+ *     [NBD_DEVICE_CONNECTED]
+ */
+enum {
+	NBD_DEVICE_ITEM_UNSPEC,
+	NBD_DEVICE_ITEM,
+	__NBD_DEVICE_ITEM_MAX,
+};
+#define NBD_DEVICE_ITEM_MAX (__NBD_DEVICE_ITEM_MAX - 1)
+
+enum {
+	NBD_DEVICE_UNSPEC,
+	NBD_DEVICE_INDEX,
+	NBD_DEVICE_CONNECTED,
+	__NBD_DEVICE_MAX,
+};
+#define NBD_DEVICE_ATTR_MAX (__NBD_DEVICE_MAX - 1)
+
+/*
+ * This is the format for multiple sockets with NBD_ATTR_SOCKETS
+ *
+ * [NBD_ATTR_SOCKETS]
+ *   [NBD_SOCK_ITEM]
+ *     [NBD_SOCK_FD]
+ *   [NBD_SOCK_ITEM]
+ *     [NBD_SOCK_FD]
+ */
+enum {
+	NBD_SOCK_ITEM_UNSPEC,
+	NBD_SOCK_ITEM,
+	__NBD_SOCK_ITEM_MAX,
+};
+#define NBD_SOCK_ITEM_MAX (__NBD_SOCK_ITEM_MAX - 1)
+
+enum {
+	NBD_SOCK_UNSPEC,
+	NBD_SOCK_FD,
+	__NBD_SOCK_MAX,
+};
+#define NBD_SOCK_MAX (__NBD_SOCK_MAX - 1)
+
+enum {
+	NBD_CMD_UNSPEC,
+	NBD_CMD_CONNECT,
+	NBD_CMD_DISCONNECT,
+	NBD_CMD_RECONFIGURE,
+	NBD_CMD_LINK_DEAD,
+	NBD_CMD_STATUS,
+	__NBD_CMD_MAX,
+};
+#define NBD_CMD_MAX	(__NBD_CMD_MAX - 1)
+
+#endif /* _UAPILINUX_NBD_NETLINK_H */
diff --git a/include/uapi/linux/nbd.h b/include/uapi/linux/nbd.h
index c91c642ea900..155e33f81913 100644
--- a/include/uapi/linux/nbd.h
+++ b/include/uapi/linux/nbd.h
@@ -37,7 +37,7 @@ enum {
 	NBD_CMD_TRIM = 4
 };
 
-/* values for flags field */
+/* values for flags field, these are server interaction specific. */
 #define NBD_FLAG_HAS_FLAGS	(1 << 0) /* nbd-server supports flags */
 #define NBD_FLAG_READ_ONLY	(1 << 1) /* device is read-only */
 #define NBD_FLAG_SEND_FLUSH	(1 << 2) /* can flush writeback cache */
@@ -45,6 +45,10 @@ enum {
 #define NBD_FLAG_SEND_TRIM	(1 << 5) /* send trim/discard */
 #define NBD_FLAG_CAN_MULTI_CONN	(1 << 8)	/* Server supports multiple connections per export. */
 
+/* These are client behavior specific flags. */
+#define NBD_CFLAG_DESTROY_ON_DISCONNECT	(1 << 0) /* delete the nbd device on
+						    disconnect. */
+
 /* userspace doesn't need the nbd_device structure */
 
 /* These are sent over the network in the request/reply magic fields */