Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block

Pull core block layer updates from Jens Axboe:
 "This is the main pull request for block storage for 4.15-rc1.

  Nothing out of the ordinary in here, and no API changes or anything
  like that. Just various new features for drivers, core changes, etc.
  In particular, this pull request contains:

   - A patch series from Bart, closing the whole on blk/scsi-mq queue
     quescing.

   - A series from Christoph, building towards hidden gendisks (for
     multipath) and ability to move bio chains around.

   - NVMe
        - Support for native multipath for NVMe (Christoph).
        - Userspace notifications for AENs (Keith).
        - Command side-effects support (Keith).
        - SGL support (Chaitanya Kulkarni)
        - FC fixes and improvements (James Smart)
        - Lots of fixes and tweaks (Various)

   - bcache
        - New maintainer (Michael Lyle)
        - Writeback control improvements (Michael)
        - Various fixes (Coly, Elena, Eric, Liang, et al)

   - lightnvm updates, mostly centered around the pblk interface
     (Javier, Hans, and Rakesh).

   - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)

   - Writeback series that fix the much discussed hundreds of millions
     of sync-all units. This goes all the way, as discussed previously
     (me).

   - Fix for missing wakeup on writeback timer adjustments (Yafang
     Shao).

   - Fix laptop mode on blk-mq (me).

   - {mq,name} tupple lookup for IO schedulers, allowing us to have
     alias names. This means you can use 'deadline' on both !mq and on
     mq (where it's called mq-deadline). (me).

   - blktrace race fix, oopsing on sg load (me).

   - blk-mq optimizations (me).

   - Obscure waitqueue race fix for kyber (Omar).

   - NBD fixes (Josef).

   - Disable writeback throttling by default on bfq, like we do on cfq
     (Luca Miccio).

   - Series from Ming that enable us to treat flush requests on blk-mq
     like any other request. This is a really nice cleanup.

   - Series from Ming that improves merging on blk-mq with schedulers,
     getting us closer to flipping the switch on scsi-mq again.

   - BFQ updates (Paolo).

   - blk-mq atomic flags memory ordering fixes (Peter Z).

   - Loop cgroup support (Shaohua).

   - Lots of minor fixes from lots of different folks, both for core and
     driver code"

* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
  nvme: fix visibility of "uuid" ns attribute
  blk-mq: fixup some comment typos and lengths
  ide: ide-atapi: fix compile error with defining macro DEBUG
  blk-mq: improve tag waiting setup for non-shared tags
  brd: remove unused brd_mutex
  blk-mq: only run the hardware queue if IO is pending
  block: avoid null pointer dereference on null disk
  fs: guard_bio_eod() needs to consider partitions
  xtensa/simdisk: fix compile error
  nvme: expose subsys attribute to sysfs
  nvme: create 'slaves' and 'holders' entries for hidden controllers
  block: create 'slaves' and 'holders' entries for hidden gendisks
  nvme: also expose the namespace identification sysfs files for mpath nodes
  nvme: implement multipath access to nvme subsystems
  nvme: track shared namespaces
  nvme: introduce a nvme_ns_ids structure
  nvme: track subsystems
  block, nvme: Introduce blk_mq_req_flags_t
  block, scsi: Make SCSI quiesce and resume work reliably
  block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
  ...

18 files changed, 201 insertions, 139 deletions

diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index fff4cfa0c21d..bfe86b54f6c1 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -25,6 +25,7 @@ enum wb_state {
 	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} */
+	WB_start_all,		/* nr_pages == 0 (all) work pending */
 };
 
 enum wb_congested_state {
@@ -45,6 +46,28 @@ enum wb_stat_item {
 #define WB_STAT_BATCH (8*(1+ilog2(nr_cpu_ids)))
 
 /*
+ * why some writeback work was initiated
+ */
+enum wb_reason {
+	WB_REASON_BACKGROUND,
+	WB_REASON_VMSCAN,
+	WB_REASON_SYNC,
+	WB_REASON_PERIODIC,
+	WB_REASON_LAPTOP_TIMER,
+	WB_REASON_FREE_MORE_MEM,
+	WB_REASON_FS_FREE_SPACE,
+	/*
+	 * There is no bdi forker thread any more and works are done
+	 * by emergency worker, however, this is TPs userland visible
+	 * and we'll be exposing exactly the same information,
+	 * so it has a mismatch name.
+	 */
+	WB_REASON_FORKER_THREAD,
+
+	WB_REASON_MAX,
+};
+
+/*
  * For cgroup writeback, multiple wb's may map to the same blkcg.  Those
  * wb's can operate mostly independently but should share the congested
  * state.  To facilitate such sharing, the congested state is tracked using
@@ -116,6 +139,7 @@ struct bdi_writeback {
 
 	struct fprop_local_percpu completions;
 	int dirty_exceeded;
+	enum wb_reason start_all_reason;
 
 	spinlock_t work_lock;		/* protects work_list & dwork scheduling */
 	struct list_head work_list;
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 16621579a3db..f41ca8486e02 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -39,8 +39,6 @@ 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);
 void wb_start_background_writeback(struct bdi_writeback *wb);
 void wb_workfn(struct work_struct *work);
 void wb_wakeup_delayed(struct bdi_writeback *wb);
@@ -175,8 +173,6 @@ static inline int wb_congested(struct bdi_writeback *wb, int cong_bits)
 
 long congestion_wait(int sync, long timeout);
 long wait_iff_congested(struct pglist_data *pgdat, int sync, long timeout);
-int pdflush_proc_obsolete(struct ctl_table *table, int write,
-		void __user *buffer, size_t *lenp, loff_t *ppos);
 
 static inline bool bdi_cap_stable_pages_required(struct backing_dev_info *bdi)
 {
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 275c91c99516..d4eec19a6d3c 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -129,18 +129,6 @@ static inline void *bio_data(struct bio *bio)
 #define bvec_to_phys(bv)	(page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
 
 /*
- * queues that have highmem support enabled may still need to revert to
- * PIO transfers occasionally and thus map high pages temporarily. For
- * permanent PIO fall back, user is probably better off disabling highmem
- * I/O completely on that queue (see ide-dma for example)
- */
-#define __bio_kmap_atomic(bio, iter)				\
-	(kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) +	\
-		bio_iter_iovec((bio), (iter)).bv_offset)
-
-#define __bio_kunmap_atomic(addr)	kunmap_atomic(addr)
-
-/*
  * merge helpers etc
  */
 
@@ -522,13 +510,11 @@ do {						\
 
 #ifdef CONFIG_BLK_CGROUP
 int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
-int bio_associate_current(struct bio *bio);
 void bio_disassociate_task(struct bio *bio);
 void bio_clone_blkcg_association(struct bio *dst, struct bio *src);
 #else	/* CONFIG_BLK_CGROUP */
 static inline int bio_associate_blkcg(struct bio *bio,
 			struct cgroup_subsys_state *blkcg_css) { return 0; }
-static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
 static inline void bio_disassociate_task(struct bio *bio) { }
 static inline void bio_clone_blkcg_association(struct bio *dst,
 			struct bio *src) { }
@@ -575,17 +561,6 @@ static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
 }
 #endif
 
-static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
-				   unsigned long *flags)
-{
-	return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
-}
-#define __bio_kunmap_irq(buf, flags)	bvec_kunmap_irq(buf, flags)
-
-#define bio_kmap_irq(bio, flags) \
-	__bio_kmap_irq((bio), (bio)->bi_iter, (flags))
-#define bio_kunmap_irq(buf,flags)	__bio_kunmap_irq(buf, flags)
-
 /*
  * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
  *
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index 8bbc3716507a..e9825ff57b15 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -20,6 +20,7 @@
 #include <linux/radix-tree.h>
 #include <linux/blkdev.h>
 #include <linux/atomic.h>
+#include <linux/kthread.h>
 
 /* percpu_counter batch for blkg_[rw]stats, per-cpu drift doesn't matter */
 #define BLKG_STAT_CPU_BATCH	(INT_MAX / 2)
@@ -224,22 +225,16 @@ static inline struct blkcg *css_to_blkcg(struct cgroup_subsys_state *css)
 	return css ? container_of(css, struct blkcg, css) : NULL;
 }
 
-static inline struct blkcg *task_blkcg(struct task_struct *tsk)
-{
-	return css_to_blkcg(task_css(tsk, io_cgrp_id));
-}
-
 static inline struct blkcg *bio_blkcg(struct bio *bio)
 {
+	struct cgroup_subsys_state *css;
+
 	if (bio && bio->bi_css)
 		return css_to_blkcg(bio->bi_css);
-	return task_blkcg(current);
-}
-
-static inline struct cgroup_subsys_state *
-task_get_blkcg_css(struct task_struct *task)
-{
-	return task_get_css(task, io_cgrp_id);
+	css = kthread_blkcg();
+	if (css)
+		return css_to_blkcg(css);
+	return css_to_blkcg(task_css(current, io_cgrp_id));
 }
 
 /**
@@ -736,12 +731,6 @@ struct blkcg_policy {
 
 #define blkcg_root_css	((struct cgroup_subsys_state *)ERR_PTR(-EINVAL))
 
-static inline struct cgroup_subsys_state *
-task_get_blkcg_css(struct task_struct *task)
-{
-	return NULL;
-}
-
 #ifdef CONFIG_BLOCK
 
 static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; }
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 994cbb0f7ffc..95c9a5c862e2 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -31,10 +31,12 @@ struct blk_mq_hw_ctx {
 
 	struct sbitmap		ctx_map;
 
+	struct blk_mq_ctx	*dispatch_from;
+
 	struct blk_mq_ctx	**ctxs;
 	unsigned int		nr_ctx;
 
-	wait_queue_entry_t		dispatch_wait;
+	wait_queue_entry_t	dispatch_wait;
 	atomic_t		wait_index;
 
 	struct blk_mq_tags	*tags;
@@ -91,6 +93,8 @@ struct blk_mq_queue_data {
 
 typedef blk_status_t (queue_rq_fn)(struct blk_mq_hw_ctx *,
 		const struct blk_mq_queue_data *);
+typedef bool (get_budget_fn)(struct blk_mq_hw_ctx *);
+typedef void (put_budget_fn)(struct blk_mq_hw_ctx *);
 typedef enum blk_eh_timer_return (timeout_fn)(struct request *, bool);
 typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int);
 typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
@@ -113,6 +117,15 @@ struct blk_mq_ops {
 	queue_rq_fn		*queue_rq;
 
 	/*
+	 * Reserve budget before queue request, once .queue_rq is
+	 * run, it is driver's responsibility to release the
+	 * reserved budget. Also we have to handle failure case
+	 * of .get_budget for avoiding I/O deadlock.
+	 */
+	get_budget_fn		*get_budget;
+	put_budget_fn		*put_budget;
+
+	/*
 	 * Called on request timeout
 	 */
 	timeout_fn		*timeout;
@@ -169,8 +182,7 @@ enum {
 	BLK_MQ_S_STOPPED	= 0,
 	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_S_START_ON_RUN	= 3,
 
 	BLK_MQ_MAX_DEPTH	= 10240,
 
@@ -198,15 +210,21 @@ void blk_mq_free_request(struct request *rq);
 bool blk_mq_can_queue(struct blk_mq_hw_ctx *);
 
 enum {
-	BLK_MQ_REQ_NOWAIT	= (1 << 0), /* return when out of requests */
-	BLK_MQ_REQ_RESERVED	= (1 << 1), /* allocate from reserved pool */
-	BLK_MQ_REQ_INTERNAL	= (1 << 2), /* allocate internal/sched tag */
+	/* return when out of requests */
+	BLK_MQ_REQ_NOWAIT	= (__force blk_mq_req_flags_t)(1 << 0),
+	/* allocate from reserved pool */
+	BLK_MQ_REQ_RESERVED	= (__force blk_mq_req_flags_t)(1 << 1),
+	/* allocate internal/sched tag */
+	BLK_MQ_REQ_INTERNAL	= (__force blk_mq_req_flags_t)(1 << 2),
+	/* set RQF_PREEMPT */
+	BLK_MQ_REQ_PREEMPT	= (__force blk_mq_req_flags_t)(1 << 3),
 };
 
 struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
-		unsigned int flags);
+		blk_mq_req_flags_t flags);
 struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
-		unsigned int op, unsigned int flags, unsigned int hctx_idx);
+		unsigned int op, blk_mq_req_flags_t flags,
+		unsigned int hctx_idx);
 struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag);
 
 enum {
@@ -249,7 +267,7 @@ void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
 void blk_mq_quiesce_queue(struct request_queue *q);
 void blk_mq_unquiesce_queue(struct request_queue *q);
 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);
+bool 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,
@@ -260,8 +278,8 @@ 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);
-int blk_mq_reinit_tagset(struct blk_mq_tag_set *set,
-			 int (reinit_request)(void *, struct request *));
+int blk_mq_tagset_iter(struct blk_mq_tag_set *set, void *data,
+		int (reinit_request)(void *, struct request *));
 
 int blk_mq_map_queues(struct blk_mq_tag_set *set);
 void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues);
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 96ac3815542c..a1e628e032da 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -163,6 +163,8 @@ struct bio {
  */
 #define BIO_RESET_BITS	BVEC_POOL_OFFSET
 
+typedef __u32 __bitwise blk_mq_req_flags_t;
+
 /*
  * Operations and flags common to the bio and request structures.
  * We use 8 bits for encoding the operation, and the remaining 24 for flags.
@@ -225,11 +227,14 @@ enum req_flag_bits {
 	__REQ_PREFLUSH,		/* request for cache flush */
 	__REQ_RAHEAD,		/* read ahead, can fail anytime */
 	__REQ_BACKGROUND,	/* background IO */
+	__REQ_NOWAIT,           /* Don't wait if request will block */
 
 	/* command specific flags for REQ_OP_WRITE_ZEROES: */
 	__REQ_NOUNMAP,		/* do not free blocks when zeroing */
 
-	__REQ_NOWAIT,           /* Don't wait if request will block */
+	/* for driver use */
+	__REQ_DRV,
+
 	__REQ_NR_BITS,		/* stops here */
 };
 
@@ -246,9 +251,11 @@ enum req_flag_bits {
 #define REQ_PREFLUSH		(1ULL << __REQ_PREFLUSH)
 #define REQ_RAHEAD		(1ULL << __REQ_RAHEAD)
 #define REQ_BACKGROUND		(1ULL << __REQ_BACKGROUND)
+#define REQ_NOWAIT		(1ULL << __REQ_NOWAIT)
 
 #define REQ_NOUNMAP		(1ULL << __REQ_NOUNMAP)
-#define REQ_NOWAIT		(1ULL << __REQ_NOWAIT)
+
+#define REQ_DRV			(1ULL << __REQ_DRV)
 
 #define REQ_FAILFAST_MASK \
 	(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
@@ -330,11 +337,10 @@ static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
 }
 
 struct blk_rq_stat {
-	s64 mean;
+	u64 mean;
 	u64 min;
 	u64 max;
-	s32 nr_samples;
-	s32 nr_batch;
+	u32 nr_samples;
 	u64 batch;
 };
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8da66379f7ea..8089ca17db9a 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -267,6 +267,7 @@ struct blk_queue_ctx;
 
 typedef void (request_fn_proc) (struct request_queue *q);
 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
+typedef bool (poll_q_fn) (struct request_queue *q, blk_qc_t);
 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
 
@@ -409,6 +410,7 @@ struct request_queue {
 
 	request_fn_proc		*request_fn;
 	make_request_fn		*make_request_fn;
+	poll_q_fn		*poll_fn;
 	prep_rq_fn		*prep_rq_fn;
 	unprep_rq_fn		*unprep_rq_fn;
 	softirq_done_fn		*softirq_done_fn;
@@ -610,7 +612,6 @@ struct request_queue {
 #define QUEUE_FLAG_NOMERGES     5	/* disable merge attempts */
 #define QUEUE_FLAG_SAME_COMP	6	/* complete on same CPU-group */
 #define QUEUE_FLAG_FAIL_IO	7	/* fake timeout */
-#define QUEUE_FLAG_STACKABLE	8	/* supports request stacking */
 #define QUEUE_FLAG_NONROT	9	/* non-rotational device (SSD) */
 #define QUEUE_FLAG_VIRT        QUEUE_FLAG_NONROT /* paravirt device */
 #define QUEUE_FLAG_IO_STAT     10	/* do IO stats */
@@ -632,14 +633,13 @@ struct request_queue {
 #define QUEUE_FLAG_REGISTERED  26	/* queue has been registered to a disk */
 #define QUEUE_FLAG_SCSI_PASSTHROUGH 27	/* queue supports SCSI commands */
 #define QUEUE_FLAG_QUIESCED    28	/* queue has been quiesced */
+#define QUEUE_FLAG_PREEMPT_ONLY	29	/* only process REQ_PREEMPT requests */
 
 #define QUEUE_FLAG_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
-				 (1 << QUEUE_FLAG_STACKABLE)	|	\
 				 (1 << QUEUE_FLAG_SAME_COMP)	|	\
 				 (1 << QUEUE_FLAG_ADD_RANDOM))
 
 #define QUEUE_FLAG_MQ_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
-				 (1 << QUEUE_FLAG_STACKABLE)	|	\
 				 (1 << QUEUE_FLAG_SAME_COMP)	|	\
 				 (1 << QUEUE_FLAG_POLL))
 
@@ -723,8 +723,6 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 #define blk_queue_nonrot(q)	test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
 #define blk_queue_io_stat(q)	test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
 #define blk_queue_add_random(q)	test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
-#define blk_queue_stackable(q)	\
-	test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
 #define blk_queue_discard(q)	test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
 #define blk_queue_secure_erase(q) \
 	(test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
@@ -736,6 +734,11 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 	((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
 			     REQ_FAILFAST_DRIVER))
 #define blk_queue_quiesced(q)	test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
+#define blk_queue_preempt_only(q)				\
+	test_bit(QUEUE_FLAG_PREEMPT_ONLY, &(q)->queue_flags)
+
+extern int blk_set_preempt_only(struct request_queue *q);
+extern void blk_clear_preempt_only(struct request_queue *q);
 
 static inline bool blk_account_rq(struct request *rq)
 {
@@ -923,24 +926,17 @@ static inline void rq_flush_dcache_pages(struct request *rq)
 }
 #endif
 
-#ifdef CONFIG_PRINTK
-#define vfs_msg(sb, level, fmt, ...)				\
-	__vfs_msg(sb, level, fmt, ##__VA_ARGS__)
-#else
-#define vfs_msg(sb, level, fmt, ...)				\
-do {								\
-	no_printk(fmt, ##__VA_ARGS__);				\
-	__vfs_msg(sb, "", " ");					\
-} while (0)
-#endif
-
 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 blk_qc_t direct_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_flags(struct request_queue *,
+					     unsigned int op,
+					     blk_mq_req_flags_t flags);
 extern struct request *blk_get_request(struct request_queue *, unsigned int op,
 				       gfp_t gfp_mask);
 extern void blk_requeue_request(struct request_queue *, struct request *);
@@ -964,7 +960,7 @@ extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
 			 struct scsi_ioctl_command __user *);
 
-extern int blk_queue_enter(struct request_queue *q, bool nowait);
+extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
 extern void blk_queue_exit(struct request_queue *q);
 extern void blk_start_queue(struct request_queue *q);
 extern void blk_start_queue_async(struct request_queue *q);
@@ -991,7 +987,7 @@ extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
 int blk_status_to_errno(blk_status_t status);
 blk_status_t errno_to_blk_status(int errno);
 
-bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie);
+bool blk_poll(struct request_queue *q, blk_qc_t cookie);
 
 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
 {
@@ -1110,6 +1106,8 @@ extern struct request *blk_peek_request(struct request_queue *q);
 extern void blk_start_request(struct request *rq);
 extern struct request *blk_fetch_request(struct request_queue *q);
 
+void blk_steal_bios(struct bio_list *list, struct request *rq);
+
 /*
  * Request completion related functions.
  *
@@ -1372,7 +1370,7 @@ static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
 				    gfp_mask, 0);
 }
 
-extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
+extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
 
 enum blk_default_limits {
 	BLK_MAX_SEGMENTS	= 128,
diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index afa37f807f12..8b1bf8d3d4a2 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -157,7 +157,7 @@ void set_bh_page(struct buffer_head *bh,
 		struct page *page, unsigned long offset);
 int try_to_free_buffers(struct page *);
 struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
-		int retry);
+		bool retry);
 void create_empty_buffers(struct page *, unsigned long,
 			unsigned long b_state);
 void end_buffer_read_sync(struct buffer_head *bh, int uptodate);
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index ddb7632d73b9..3d794b3dc532 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -145,6 +145,7 @@ struct elevator_type
 	size_t icq_align;	/* ditto */
 	struct elv_fs_entry *elevator_attrs;
 	char elevator_name[ELV_NAME_MAX];
+	const char *elevator_alias;
 	struct module *elevator_owner;
 	bool uses_mq;
 #ifdef CONFIG_BLK_DEBUG_FS
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index eaefb7a62f83..5144ebe046c9 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -141,6 +141,7 @@ struct hd_struct {
 #define GENHD_FL_NATIVE_CAPACITY		128
 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE	256
 #define GENHD_FL_NO_PART_SCAN			512
+#define GENHD_FL_HIDDEN				1024
 
 enum {
 	DISK_EVENT_MEDIA_CHANGE			= 1 << 0, /* media changed */
@@ -236,7 +237,7 @@ static inline bool disk_part_scan_enabled(struct gendisk *disk)
 
 static inline dev_t disk_devt(struct gendisk *disk)
 {
-	return disk_to_dev(disk)->devt;
+	return MKDEV(disk->major, disk->first_minor);
 }
 
 static inline dev_t part_devt(struct hd_struct *part)
@@ -244,6 +245,7 @@ static inline dev_t part_devt(struct hd_struct *part)
 	return part_to_dev(part)->devt;
 }
 
+extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 
 static inline void disk_put_part(struct hd_struct *part)
diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 86d53a3cb497..3203e36b2ee8 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -4,6 +4,7 @@
 /* Simple interface for creating and stopping kernel threads without mess. */
 #include <linux/err.h>
 #include <linux/sched.h>
+#include <linux/cgroup.h>
 
 __printf(4, 5)
 struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
@@ -199,4 +200,14 @@ bool kthread_cancel_delayed_work_sync(struct kthread_delayed_work *work);
 
 void kthread_destroy_worker(struct kthread_worker *worker);
 
+#ifdef CONFIG_BLK_CGROUP
+void kthread_associate_blkcg(struct cgroup_subsys_state *css);
+struct cgroup_subsys_state *kthread_blkcg(void);
+#else
+static inline void kthread_associate_blkcg(struct cgroup_subsys_state *css) { }
+static inline struct cgroup_subsys_state *kthread_blkcg(void)
+{
+	return NULL;
+}
+#endif
 #endif /* _LINUX_KTHREAD_H */
diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
index a29a8db5cc2f..2d1d9de06728 100644
--- a/include/linux/lightnvm.h
+++ b/include/linux/lightnvm.h
@@ -57,6 +57,7 @@ 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_submit_io_sync_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,
@@ -70,6 +71,7 @@ struct nvm_dev_ops {
 	nvm_op_set_bb_fn	*set_bb_tbl;
 
 	nvm_submit_io_fn	*submit_io;
+	nvm_submit_io_sync_fn	*submit_io_sync;
 
 	nvm_create_dma_pool_fn	*create_dma_pool;
 	nvm_destroy_dma_pool_fn	*destroy_dma_pool;
@@ -461,10 +463,9 @@ struct nvm_tgt_type {
 
 	/* For internal use */
 	struct list_head list;
+	struct module *owner;
 };
 
-extern struct nvm_tgt_type *nvm_find_target_type(const char *, int);
-
 extern int nvm_register_tgt_type(struct nvm_tgt_type *);
 extern void nvm_unregister_tgt_type(struct nvm_tgt_type *);
 
@@ -479,10 +480,8 @@ 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_submit_io_sync(struct nvm_tgt_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_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);
@@ -491,8 +490,6 @@ extern void nvm_end_io(struct nvm_rq *);
 extern int nvm_bb_tbl_fold(struct nvm_dev *, u8 *, int);
 extern int nvm_get_tgt_bb_tbl(struct nvm_tgt_dev *, struct ppa_addr, u8 *);
 
-extern int nvm_dev_factory(struct nvm_dev *, int flags);
-
 extern void nvm_part_to_tgt(struct nvm_dev *, sector_t *, int);
 
 #else /* CONFIG_NVM */
diff --git a/include/linux/nvme-fc-driver.h b/include/linux/nvme-fc-driver.h
index a726f96010d5..496ff759f84c 100644
--- a/include/linux/nvme-fc-driver.h
+++ b/include/linux/nvme-fc-driver.h
@@ -40,6 +40,8 @@
  * @node_name: FC WWNN for the port
  * @port_name: FC WWPN for the port
  * @port_role: What NVME roles are supported (see FC_PORT_ROLE_xxx)
+ * @dev_loss_tmo: maximum delay for reconnects to an association on
+ *             this device. Used only on a remoteport.
  *
  * Initialization values for dynamic port fields:
  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
@@ -50,6 +52,7 @@ struct nvme_fc_port_info {
 	u64			port_name;
 	u32			port_role;
 	u32			port_id;
+	u32			dev_loss_tmo;
 };
 
 
@@ -102,8 +105,6 @@ enum nvmefc_fcp_datadir {
 };
 
 
-#define NVME_FC_MAX_SEGMENTS		256
-
 /**
  * struct nvmefc_fcp_req - Request structure passed from NVME-FC transport
  *                         to LLDD in order to perform a NVME FCP IO operation.
@@ -202,6 +203,9 @@ enum nvme_fc_obj_state {
  *             The length of the buffer corresponds to the local_priv_sz
  *             value specified in the nvme_fc_port_template supplied by
  *             the LLDD.
+ * @dev_loss_tmo: maximum delay for reconnects to an association on
+ *             this device. To modify, lldd must call
+ *             nvme_fc_set_remoteport_devloss().
  *
  * Fields with dynamic values. Values may change base on link state. LLDD
  * may reference fields directly to change them. Initialized by the
@@ -259,10 +263,9 @@ struct nvme_fc_remote_port {
 	u32 port_role;
 	u64 node_name;
 	u64 port_name;
-
 	struct nvme_fc_local_port *localport;
-
 	void *private;
+	u32 dev_loss_tmo;
 
 	/* dynamic fields */
 	u32 port_id;
@@ -446,6 +449,10 @@ int nvme_fc_register_remoteport(struct nvme_fc_local_port *localport,
 
 int nvme_fc_unregister_remoteport(struct nvme_fc_remote_port *remoteport);
 
+void nvme_fc_rescan_remoteport(struct nvme_fc_remote_port *remoteport);
+
+int nvme_fc_set_remoteport_devloss(struct nvme_fc_remote_port *remoteport,
+			u32 dev_loss_tmo);
 
 
 /*
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 9310ce77d8e1..aea87f0d917b 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -90,6 +90,14 @@ enum {
 };
 
 #define NVME_AQ_DEPTH		32
+#define NVME_NR_AEN_COMMANDS	1
+#define NVME_AQ_BLK_MQ_DEPTH	(NVME_AQ_DEPTH - NVME_NR_AEN_COMMANDS)
+
+/*
+ * Subtract one to leave an empty queue entry for 'Full Queue' condition. See
+ * NVM-Express 1.2 specification, section 4.1.2.
+ */
+#define NVME_AQ_MQ_TAG_DEPTH	(NVME_AQ_BLK_MQ_DEPTH - 1)
 
 enum {
 	NVME_REG_CAP	= 0x0000,	/* Controller Capabilities */
@@ -267,6 +275,7 @@ enum {
 	NVME_CTRL_OACS_SEC_SUPP                 = 1 << 0,
 	NVME_CTRL_OACS_DIRECTIVES		= 1 << 5,
 	NVME_CTRL_OACS_DBBUF_SUPP		= 1 << 8,
+	NVME_CTRL_LPA_CMD_EFFECTS_LOG		= 1 << 1,
 };
 
 struct nvme_lbaf {
@@ -396,6 +405,21 @@ struct nvme_fw_slot_info_log {
 };
 
 enum {
+	NVME_CMD_EFFECTS_CSUPP		= 1 << 0,
+	NVME_CMD_EFFECTS_LBCC		= 1 << 1,
+	NVME_CMD_EFFECTS_NCC		= 1 << 2,
+	NVME_CMD_EFFECTS_NIC		= 1 << 3,
+	NVME_CMD_EFFECTS_CCC		= 1 << 4,
+	NVME_CMD_EFFECTS_CSE_MASK	= 3 << 16,
+};
+
+struct nvme_effects_log {
+	__le32 acs[256];
+	__le32 iocs[256];
+	__u8   resv[2048];
+};
+
+enum {
 	NVME_SMART_CRIT_SPARE		= 1 << 0,
 	NVME_SMART_CRIT_TEMPERATURE	= 1 << 1,
 	NVME_SMART_CRIT_RELIABILITY	= 1 << 2,
@@ -404,6 +428,10 @@ enum {
 };
 
 enum {
+	NVME_AER_ERROR			= 0,
+	NVME_AER_SMART			= 1,
+	NVME_AER_CSS			= 6,
+	NVME_AER_VS			= 7,
 	NVME_AER_NOTICE_NS_CHANGED	= 0x0002,
 	NVME_AER_NOTICE_FW_ACT_STARTING = 0x0102,
 };
@@ -681,6 +709,7 @@ enum nvme_admin_opcode {
 	nvme_admin_format_nvm		= 0x80,
 	nvme_admin_security_send	= 0x81,
 	nvme_admin_security_recv	= 0x82,
+	nvme_admin_sanitize_nvm		= 0x84,
 };
 
 enum {
@@ -712,6 +741,7 @@ enum {
 	NVME_LOG_ERROR		= 0x01,
 	NVME_LOG_SMART		= 0x02,
 	NVME_LOG_FW_SLOT	= 0x03,
+	NVME_LOG_CMD_EFFECTS	= 0x05,
 	NVME_LOG_DISC		= 0x70,
 	NVME_LOG_RESERVATION	= 0x80,
 	NVME_FWACT_REPL		= (0 << 3),
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index a1904aadbc45..0dcc60e820de 100644
--- a/include/linux/sbitmap.h
+++ b/include/linux/sbitmap.h
@@ -211,10 +211,14 @@ bool sbitmap_any_bit_set(const struct sbitmap *sb);
  */
 bool sbitmap_any_bit_clear(const struct sbitmap *sb);
 
+#define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift)
+#define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U))
+
 typedef bool (*sb_for_each_fn)(struct sbitmap *, unsigned int, void *);
 
 /**
- * sbitmap_for_each_set() - Iterate over each set bit in a &struct sbitmap.
+ * __sbitmap_for_each_set() - Iterate over each set bit in a &struct sbitmap.
+ * @start: Where to start the iteration.
  * @sb: Bitmap to iterate over.
  * @fn: Callback. Should return true to continue or false to break early.
  * @data: Pointer to pass to callback.
@@ -222,35 +226,61 @@ typedef bool (*sb_for_each_fn)(struct sbitmap *, unsigned int, void *);
  * This is inline even though it's non-trivial so that the function calls to the
  * callback will hopefully get optimized away.
  */
-static inline void sbitmap_for_each_set(struct sbitmap *sb, sb_for_each_fn fn,
-					void *data)
+static inline void __sbitmap_for_each_set(struct sbitmap *sb,
+					  unsigned int start,
+					  sb_for_each_fn fn, void *data)
 {
-	unsigned int i;
+	unsigned int index;
+	unsigned int nr;
+	unsigned int scanned = 0;
 
-	for (i = 0; i < sb->map_nr; i++) {
-		struct sbitmap_word *word = &sb->map[i];
-		unsigned int off, nr;
+	if (start >= sb->depth)
+		start = 0;
+	index = SB_NR_TO_INDEX(sb, start);
+	nr = SB_NR_TO_BIT(sb, start);
 
-		if (!word->word)
-			continue;
+	while (scanned < sb->depth) {
+		struct sbitmap_word *word = &sb->map[index];
+		unsigned int depth = min_t(unsigned int, word->depth - nr,
+					   sb->depth - scanned);
 
-		nr = 0;
-		off = i << sb->shift;
+		scanned += depth;
+		if (!word->word)
+			goto next;
+
+		/*
+		 * On the first iteration of the outer loop, we need to add the
+		 * bit offset back to the size of the word for find_next_bit().
+		 * On all other iterations, nr is zero, so this is a noop.
+		 */
+		depth += nr;
 		while (1) {
-			nr = find_next_bit(&word->word, word->depth, nr);
-			if (nr >= word->depth)
+			nr = find_next_bit(&word->word, depth, nr);
+			if (nr >= depth)
 				break;
-
-			if (!fn(sb, off + nr, data))
+			if (!fn(sb, (index << sb->shift) + nr, data))
 				return;
 
 			nr++;
 		}
+next:
+		nr = 0;
+		if (++index >= sb->map_nr)
+			index = 0;
 	}
 }
 
-#define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift)
-#define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U))
+/**
+ * sbitmap_for_each_set() - Iterate over each set bit in a &struct sbitmap.
+ * @sb: Bitmap to iterate over.
+ * @fn: Callback. Should return true to continue or false to break early.
+ * @data: Pointer to pass to callback.
+ */
+static inline void sbitmap_for_each_set(struct sbitmap *sb, sb_for_each_fn fn,
+					void *data)
+{
+	__sbitmap_for_each_set(sb, 0, fn, data);
+}
 
 static inline unsigned long *__sbitmap_word(struct sbitmap *sb,
 					    unsigned int bitnr)
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index e12d92808e98..f42d85631d17 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -43,28 +43,6 @@ enum writeback_sync_modes {
 };
 
 /*
- * why some writeback work was initiated
- */
-enum wb_reason {
-	WB_REASON_BACKGROUND,
-	WB_REASON_VMSCAN,
-	WB_REASON_SYNC,
-	WB_REASON_PERIODIC,
-	WB_REASON_LAPTOP_TIMER,
-	WB_REASON_FREE_MORE_MEM,
-	WB_REASON_FS_FREE_SPACE,
-	/*
-	 * There is no bdi forker thread any more and works are done
-	 * by emergency worker, however, this is TPs userland visible
-	 * and we'll be exposing exactly the same information,
-	 * so it has a mismatch name.
-	 */
-	WB_REASON_FORKER_THREAD,
-
-	WB_REASON_MAX,
-};
-
-/*
  * A control structure which tells the writeback code what to do.  These are
  * always on the stack, and hence need no locking.  They are always initialised
  * in a manner such that unspecified fields are set to zero.
@@ -186,11 +164,11 @@ struct bdi_writeback;
 void writeback_inodes_sb(struct super_block *, enum wb_reason reason);
 void writeback_inodes_sb_nr(struct super_block *, unsigned long nr,
 							enum wb_reason reason);
-bool try_to_writeback_inodes_sb(struct super_block *, enum wb_reason reason);
-bool try_to_writeback_inodes_sb_nr(struct super_block *, unsigned long nr,
-				   enum wb_reason reason);
+void try_to_writeback_inodes_sb(struct super_block *sb, enum wb_reason reason);
 void sync_inodes_sb(struct super_block *);
-void wakeup_flusher_threads(long nr_pages, enum wb_reason reason);
+void wakeup_flusher_threads(enum wb_reason reason);
+void wakeup_flusher_threads_bdi(struct backing_dev_info *bdi,
+				enum wb_reason reason);
 void inode_wait_for_writeback(struct inode *inode);
 
 /* writeback.h requires fs.h; it, too, is not included from here. */
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 571ddb49b926..73af87dfbff8 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -221,6 +221,7 @@ struct scsi_device {
 	unsigned char		access_state;
 	struct mutex		state_mutex;
 	enum scsi_device_state sdev_state;
+	struct task_struct	*quiesced_by;
 	unsigned long		sdev_data[0];
 } __attribute__((aligned(sizeof(unsigned long))));
 
diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index 2e1fa7910306..32db72c7c055 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -287,7 +287,6 @@ DEFINE_EVENT(writeback_class, name, \
 	TP_PROTO(struct bdi_writeback *wb), \
 	TP_ARGS(wb))
 
-DEFINE_WRITEBACK_EVENT(writeback_nowork);
 DEFINE_WRITEBACK_EVENT(writeback_wake_background);
 
 TRACE_EVENT(writeback_bdi_register,