Merge tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:

 - NVMe:
      - ZNS support (Aravind, Keith, Matias, Niklas)
      - Misc cleanups, optimizations, fixes (Baolin, Chaitanya, David,
        Dongli, Max, Sagi)

 - null_blk zone capacity support (Aravind)

 - MD:
      - raid5/6 fixes (ChangSyun)
      - Warning fixes (Damien)
      - raid5 stripe fixes (Guoqing, Song, Yufen)
      - sysfs deadlock fix (Junxiao)
      - raid10 deadlock fix (Vitaly)

 - struct_size conversions (Gustavo)

 - Set of bcache updates/fixes (Coly)

* tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block: (117 commits)
  md/raid5: Allow degraded raid6 to do rmw
  md/raid5: Fix Force reconstruct-write io stuck in degraded raid5
  raid5: don't duplicate code for different paths in handle_stripe
  raid5-cache: hold spinlock instead of mutex in r5c_journal_mode_show
  md: print errno in super_written
  md/raid5: remove the redundant setting of STRIPE_HANDLE
  md: register new md sysfs file 'uuid' read-only
  md: fix max sectors calculation for super 1.0
  nvme-loop: remove extra variable in create ctrl
  nvme-loop: set ctrl state connecting after init
  nvme-multipath: do not fall back to __nvme_find_path() for non-optimized paths
  nvme-multipath: fix logic for non-optimized paths
  nvme-rdma: fix controller reset hang during traffic
  nvme-tcp: fix controller reset hang during traffic
  nvmet: introduce the passthru Kconfig option
  nvmet: introduce the passthru configfs interface
  nvmet: Add passthru enable/disable helpers
  nvmet: add passthru code to process commands
  nvme: export nvme_find_get_ns() and nvme_put_ns()
  nvme: introduce nvme_ctrl_get_by_path()
  ...

25 files changed, 913 insertions, 355 deletions

diff --git a/drivers/md/bcache/Kconfig b/drivers/md/bcache/Kconfig
index bf7dd96db9b3..d1ca4d059c20 100644
--- a/drivers/md/bcache/Kconfig
+++ b/drivers/md/bcache/Kconfig
@@ -27,7 +27,7 @@ config BCACHE_CLOSURES_DEBUG
 	interface to list them, which makes it possible to see asynchronous
 	operations that get stuck.
 
-config BCACHE_ASYNC_REGISTRAION
+config BCACHE_ASYNC_REGISTRATION
 	bool "Asynchronous device registration (EXPERIMENTAL)"
 	depends on BCACHE
 	help
diff --git a/drivers/md/bcache/Makefile b/drivers/md/bcache/Makefile
index fd714628da6a..5b87e59676b8 100644
--- a/drivers/md/bcache/Makefile
+++ b/drivers/md/bcache/Makefile
@@ -4,4 +4,4 @@ obj-$(CONFIG_BCACHE)	+= bcache.o
 
 bcache-y		:= alloc.o bset.o btree.o closure.o debug.o extents.o\
 	io.o journal.o movinggc.o request.o stats.o super.o sysfs.o trace.o\
-	util.o writeback.o
+	util.o writeback.o features.o
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index a1df0d95151c..52035a78d836 100644
--- a/drivers/md/bcache/alloc.c
+++ b/drivers/md/bcache/alloc.c
@@ -87,7 +87,7 @@ void bch_rescale_priorities(struct cache_set *c, int sectors)
 {
 	struct cache *ca;
 	struct bucket *b;
-	unsigned int next = c->nbuckets * c->sb.bucket_size / 1024;
+	unsigned long next = c->nbuckets * c->sb.bucket_size / 1024;
 	unsigned int i;
 	int r;
 
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 3c708e8b5e2d..4fd03d2496d8 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -264,7 +264,7 @@ struct bcache_device {
 #define BCACHE_DEV_UNLINK_DONE		2
 #define BCACHE_DEV_WB_RUNNING		3
 #define BCACHE_DEV_RATE_DW_RUNNING	4
-	unsigned int		nr_stripes;
+	int			nr_stripes;
 	unsigned int		stripe_size;
 	atomic_t		*stripe_sectors_dirty;
 	unsigned long		*full_dirty_stripes;
@@ -762,11 +762,32 @@ struct bbio {
 #define bucket_bytes(c)		((c)->sb.bucket_size << 9)
 #define block_bytes(c)		((c)->sb.block_size << 9)
 
-#define prios_per_bucket(c)				\
-	((bucket_bytes(c) - sizeof(struct prio_set)) /	\
+static inline unsigned int meta_bucket_pages(struct cache_sb *sb)
+{
+	unsigned int n, max_pages;
+
+	max_pages = min_t(unsigned int,
+			  __rounddown_pow_of_two(USHRT_MAX) / PAGE_SECTORS,
+			  MAX_ORDER_NR_PAGES);
+
+	n = sb->bucket_size / PAGE_SECTORS;
+	if (n > max_pages)
+		n = max_pages;
+
+	return n;
+}
+
+static inline unsigned int meta_bucket_bytes(struct cache_sb *sb)
+{
+	return meta_bucket_pages(sb) << PAGE_SHIFT;
+}
+
+#define prios_per_bucket(ca)						\
+	((meta_bucket_bytes(&(ca)->sb) - sizeof(struct prio_set)) /	\
 	 sizeof(struct bucket_disk))
-#define prio_buckets(c)					\
-	DIV_ROUND_UP((size_t) (c)->sb.nbuckets, prios_per_bucket(c))
+
+#define prio_buckets(ca)						\
+	DIV_ROUND_UP((size_t) (ca)->sb.nbuckets, prios_per_bucket(ca))
 
 static inline size_t sector_to_bucket(struct cache_set *c, sector_t s)
 {
diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
index 4995fcaefe29..67a2c47f4201 100644
--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -322,7 +322,7 @@ int bch_btree_keys_alloc(struct btree_keys *b,
 
 	b->page_order = page_order;
 
-	t->data = (void *) __get_free_pages(gfp, b->page_order);
+	t->data = (void *) __get_free_pages(__GFP_COMP|gfp, b->page_order);
 	if (!t->data)
 		goto err;
 
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index d5c51e332046..3d8bd0692af3 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -738,7 +738,7 @@ void bch_btree_cache_free(struct cache_set *c)
 	if (c->verify_data)
 		list_move(&c->verify_data->list, &c->btree_cache);
 
-	free_pages((unsigned long) c->verify_ondisk, ilog2(bucket_pages(c)));
+	free_pages((unsigned long) c->verify_ondisk, ilog2(meta_bucket_pages(&c->sb)));
 #endif
 
 	list_splice(&c->btree_cache_freeable,
@@ -785,7 +785,15 @@ int bch_btree_cache_alloc(struct cache_set *c)
 	mutex_init(&c->verify_lock);
 
 	c->verify_ondisk = (void *)
-		__get_free_pages(GFP_KERNEL, ilog2(bucket_pages(c)));
+		__get_free_pages(GFP_KERNEL|__GFP_COMP, ilog2(meta_bucket_pages(&c->sb)));
+	if (!c->verify_ondisk) {
+		/*
+		 * Don't worry about the mca_rereserve buckets
+		 * allocated in previous for-loop, they will be
+		 * handled properly in bch_cache_set_unregister().
+		 */
+		return -ENOMEM;
+	}
 
 	c->verify_data = mca_bucket_alloc(c, &ZERO_KEY, GFP_KERNEL);
 
diff --git a/drivers/md/bcache/features.c b/drivers/md/bcache/features.c
new file mode 100644
index 000000000000..4442df48d28c
--- /dev/null
+++ b/drivers/md/bcache/features.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Feature set bits and string conversion.
+ * Inspired by ext4's features compat/incompat/ro_compat related code.
+ *
+ * Copyright 2020 Coly Li <colyli@suse.de>
+ *
+ */
+#include <linux/bcache.h>
+#include "bcache.h"
+#include "features.h"
+
+struct feature {
+	int		compat;
+	unsigned int	mask;
+	const char	*string;
+};
+
+static struct feature feature_list[] = {
+	{BCH_FEATURE_INCOMPAT, BCH_FEATURE_INCOMPAT_LARGE_BUCKET,
+		"large_bucket"},
+	{0, 0, 0 },
+};
+
+#define compose_feature_string(type)				\
+({									\
+	struct feature *f;						\
+	bool first = true;						\
+									\
+	for (f = &feature_list[0]; f->compat != 0; f++) {		\
+		if (f->compat != BCH_FEATURE_ ## type)			\
+			continue;					\
+		if (BCH_HAS_ ## type ## _FEATURE(&c->sb, f->mask)) {	\
+			if (first) {					\
+				out += snprintf(out, buf + size - out,	\
+						"[");	\
+			} else {					\
+				out += snprintf(out, buf + size - out,	\
+						" [");			\
+			}						\
+		} else if (!first) {					\
+			out += snprintf(out, buf + size - out, " ");	\
+		}							\
+									\
+		out += snprintf(out, buf + size - out, "%s", f->string);\
+									\
+		if (BCH_HAS_ ## type ## _FEATURE(&c->sb, f->mask))	\
+			out += snprintf(out, buf + size - out, "]");	\
+									\
+		first = false;						\
+	}								\
+	if (!first)							\
+		out += snprintf(out, buf + size - out, "\n");		\
+})
+
+int bch_print_cache_set_feature_compat(struct cache_set *c, char *buf, int size)
+{
+	char *out = buf;
+	compose_feature_string(COMPAT);
+	return out - buf;
+}
+
+int bch_print_cache_set_feature_ro_compat(struct cache_set *c, char *buf, int size)
+{
+	char *out = buf;
+	compose_feature_string(RO_COMPAT);
+	return out - buf;
+}
+
+int bch_print_cache_set_feature_incompat(struct cache_set *c, char *buf, int size)
+{
+	char *out = buf;
+	compose_feature_string(INCOMPAT);
+	return out - buf;
+}
diff --git a/drivers/md/bcache/features.h b/drivers/md/bcache/features.h
new file mode 100644
index 000000000000..a1653c478041
--- /dev/null
+++ b/drivers/md/bcache/features.h
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _BCACHE_FEATURES_H
+#define _BCACHE_FEATURES_H
+
+#include <linux/bcache.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+
+#define BCH_FEATURE_COMPAT		0
+#define BCH_FEATURE_RO_COMPAT		1
+#define BCH_FEATURE_INCOMPAT		2
+#define BCH_FEATURE_TYPE_MASK		0x03
+
+/* Feature set definition */
+/* Incompat feature set */
+#define BCH_FEATURE_INCOMPAT_LARGE_BUCKET	0x0001 /* 32bit bucket size */
+
+#define BCH_FEATURE_COMPAT_SUUP		0
+#define BCH_FEATURE_RO_COMPAT_SUUP	0
+#define BCH_FEATURE_INCOMPAT_SUUP	BCH_FEATURE_INCOMPAT_LARGE_BUCKET
+
+#define BCH_HAS_COMPAT_FEATURE(sb, mask) \
+		((sb)->feature_compat & (mask))
+#define BCH_HAS_RO_COMPAT_FEATURE(sb, mask) \
+		((sb)->feature_ro_compat & (mask))
+#define BCH_HAS_INCOMPAT_FEATURE(sb, mask) \
+		((sb)->feature_incompat & (mask))
+
+#define BCH_FEATURE_COMPAT_FUNCS(name, flagname) \
+static inline int bch_has_feature_##name(struct cache_sb *sb) \
+{ \
+	return (((sb)->feature_compat & \
+		BCH##_FEATURE_COMPAT_##flagname) != 0); \
+} \
+static inline void bch_set_feature_##name(struct cache_sb *sb) \
+{ \
+	(sb)->feature_compat |= \
+		BCH##_FEATURE_COMPAT_##flagname; \
+} \
+static inline void bch_clear_feature_##name(struct cache_sb *sb) \
+{ \
+	(sb)->feature_compat &= \
+		~BCH##_FEATURE_COMPAT_##flagname; \
+}
+
+#define BCH_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
+static inline int bch_has_feature_##name(struct cache_sb *sb) \
+{ \
+	return (((sb)->feature_ro_compat & \
+		BCH##_FEATURE_RO_COMPAT_##flagname) != 0); \
+} \
+static inline void bch_set_feature_##name(struct cache_sb *sb) \
+{ \
+	(sb)->feature_ro_compat |= \
+		BCH##_FEATURE_RO_COMPAT_##flagname; \
+} \
+static inline void bch_clear_feature_##name(struct cache_sb *sb) \
+{ \
+	(sb)->feature_ro_compat &= \
+		~BCH##_FEATURE_RO_COMPAT_##flagname; \
+}
+
+#define BCH_FEATURE_INCOMPAT_FUNCS(name, flagname) \
+static inline int bch_has_feature_##name(struct cache_sb *sb) \
+{ \
+	return (((sb)->feature_incompat & \
+		BCH##_FEATURE_INCOMPAT_##flagname) != 0); \
+} \
+static inline void bch_set_feature_##name(struct cache_sb *sb) \
+{ \
+	(sb)->feature_incompat |= \
+		BCH##_FEATURE_INCOMPAT_##flagname; \
+} \
+static inline void bch_clear_feature_##name(struct cache_sb *sb) \
+{ \
+	(sb)->feature_incompat &= \
+		~BCH##_FEATURE_INCOMPAT_##flagname; \
+}
+
+BCH_FEATURE_INCOMPAT_FUNCS(large_bucket, LARGE_BUCKET);
+
+int bch_print_cache_set_feature_compat(struct cache_set *c, char *buf, int size);
+int bch_print_cache_set_feature_ro_compat(struct cache_set *c, char *buf, int size);
+int bch_print_cache_set_feature_incompat(struct cache_set *c, char *buf, int size);
+
+#endif
diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c
index b25ee33b0d0b..a14a445618b4 100644
--- a/drivers/md/bcache/io.c
+++ b/drivers/md/bcache/io.c
@@ -26,7 +26,7 @@ struct bio *bch_bbio_alloc(struct cache_set *c)
 	struct bbio *b = mempool_alloc(&c->bio_meta, GFP_NOIO);
 	struct bio *bio = &b->bio;
 
-	bio_init(bio, bio->bi_inline_vecs, bucket_pages(c));
+	bio_init(bio, bio->bi_inline_vecs, meta_bucket_pages(&c->sb));
 
 	return bio;
 }
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 90aac4e2333f..77fbfd52edcf 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -217,10 +217,7 @@ int bch_journal_read(struct cache_set *c, struct list_head *list)
 		 */
 		pr_debug("falling back to linear search\n");
 
-		for (l = find_first_zero_bit(bitmap, ca->sb.njournal_buckets);
-		     l < ca->sb.njournal_buckets;
-		     l = find_next_zero_bit(bitmap, ca->sb.njournal_buckets,
-					    l + 1))
+		for_each_clear_bit(l, bitmap, ca->sb.njournal_buckets)
 			if (read_bucket(l))
 				goto bsearch;
 
@@ -999,8 +996,8 @@ int bch_journal_alloc(struct cache_set *c)
 	j->w[1].c = c;
 
 	if (!(init_fifo(&j->pin, JOURNAL_PIN, GFP_KERNEL)) ||
-	    !(j->w[0].data = (void *) __get_free_pages(GFP_KERNEL, JSET_BITS)) ||
-	    !(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL, JSET_BITS)))
+	    !(j->w[0].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)) ||
+	    !(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)))
 		return -ENOMEM;
 
 	return 0;
diff --git a/drivers/md/bcache/movinggc.c b/drivers/md/bcache/movinggc.c
index 7891fb512736..5872d6470470 100644
--- a/drivers/md/bcache/movinggc.c
+++ b/drivers/md/bcache/movinggc.c
@@ -145,8 +145,8 @@ static void read_moving(struct cache_set *c)
 			continue;
 		}
 
-		io = kzalloc(sizeof(struct moving_io) + sizeof(struct bio_vec)
-			     * DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS),
+		io = kzalloc(struct_size(io, bio.bio.bi_inline_vecs,
+					 DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS)),
 			     GFP_KERNEL);
 		if (!io)
 			goto err;
@@ -206,8 +206,8 @@ void bch_moving_gc(struct cache_set *c)
 	mutex_lock(&c->bucket_lock);
 
 	for_each_cache(ca, c, i) {
-		unsigned int sectors_to_move = 0;
-		unsigned int reserve_sectors = ca->sb.bucket_size *
+		unsigned long sectors_to_move = 0;
+		unsigned long reserve_sectors = ca->sb.bucket_size *
 			     fifo_used(&ca->free[RESERVE_MOVINGGC]);
 
 		ca->heap.used = 0;
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index a190bf47076d..c7cadaafa947 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -668,7 +668,9 @@ static void backing_request_endio(struct bio *bio)
 static void bio_complete(struct search *s)
 {
 	if (s->orig_bio) {
-		bio_end_io_acct(s->orig_bio, s->start_time);
+		/* Count on bcache device */
+		disk_end_io_acct(s->d->disk, bio_op(s->orig_bio), s->start_time);
+
 		trace_bcache_request_end(s->d, s->orig_bio);
 		s->orig_bio->bi_status = s->iop.status;
 		bio_endio(s->orig_bio);
@@ -728,8 +730,8 @@ static inline struct search *search_alloc(struct bio *bio,
 	s->recoverable		= 1;
 	s->write		= op_is_write(bio_op(bio));
 	s->read_dirty_data	= 0;
-	s->start_time		= bio_start_io_acct(bio);
-
+	/* Count on the bcache device */
+	s->start_time		= disk_start_io_acct(d->disk, bio_sectors(bio), bio_op(bio));
 	s->iop.c		= d->c;
 	s->iop.bio		= NULL;
 	s->iop.inode		= d->id;
@@ -1080,7 +1082,8 @@ static void detached_dev_end_io(struct bio *bio)
 	bio->bi_end_io = ddip->bi_end_io;
 	bio->bi_private = ddip->bi_private;
 
-	bio_end_io_acct(bio, ddip->start_time);
+	/* Count on the bcache device */
+	disk_end_io_acct(ddip->d->disk, bio_op(bio), ddip->start_time);
 
 	if (bio->bi_status) {
 		struct cached_dev *dc = container_of(ddip->d,
@@ -1105,7 +1108,8 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio)
 	 */
 	ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);
 	ddip->d = d;
-	ddip->start_time = bio_start_io_acct(bio);
+	/* Count on the bcache device */
+	ddip->start_time = disk_start_io_acct(d->disk, bio_sectors(bio), bio_op(bio));
 	ddip->bi_end_io = bio->bi_end_io;
 	ddip->bi_private = bio->bi_private;
 	bio->bi_end_io = detached_dev_end_io;
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 9e45faa054b6..1bbdc410ee3c 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -13,6 +13,7 @@
 #include "extents.h"
 #include "request.h"
 #include "writeback.h"
+#include "features.h"
 
 #include <linux/blkdev.h>
 #include <linux/debugfs.h>
@@ -59,6 +60,92 @@ struct workqueue_struct *bch_journal_wq;
 
 /* Superblock */
 
+static unsigned int get_bucket_size(struct cache_sb *sb, struct cache_sb_disk *s)
+{
+	unsigned int bucket_size = le16_to_cpu(s->bucket_size);
+
+	if (sb->version >= BCACHE_SB_VERSION_CDEV_WITH_FEATURES &&
+	     bch_has_feature_large_bucket(sb))
+		bucket_size |= le16_to_cpu(s->bucket_size_hi) << 16;
+
+	return bucket_size;
+}
+
+static const char *read_super_common(struct cache_sb *sb,  struct block_device *bdev,
+				     struct cache_sb_disk *s)
+{
+	const char *err;
+	unsigned int i;
+
+	sb->first_bucket= le16_to_cpu(s->first_bucket);
+	sb->nbuckets	= le64_to_cpu(s->nbuckets);
+	sb->bucket_size	= get_bucket_size(sb, s);
+
+	sb->nr_in_set	= le16_to_cpu(s->nr_in_set);
+	sb->nr_this_dev	= le16_to_cpu(s->nr_this_dev);
+
+	err = "Too many journal buckets";
+	if (sb->keys > SB_JOURNAL_BUCKETS)
+		goto err;
+
+	err = "Too many buckets";
+	if (sb->nbuckets > LONG_MAX)
+		goto err;
+
+	err = "Not enough buckets";
+	if (sb->nbuckets < 1 << 7)
+		goto err;
+
+	err = "Bad block size (not power of 2)";
+	if (!is_power_of_2(sb->block_size))
+		goto err;
+
+	err = "Bad block size (larger than page size)";
+	if (sb->block_size > PAGE_SECTORS)
+		goto err;
+
+	err = "Bad bucket size (not power of 2)";
+	if (!is_power_of_2(sb->bucket_size))
+		goto err;
+
+	err = "Bad bucket size (smaller than page size)";
+	if (sb->bucket_size < PAGE_SECTORS)
+		goto err;
+
+	err = "Invalid superblock: device too small";
+	if (get_capacity(bdev->bd_disk) <
+	    sb->bucket_size * sb->nbuckets)
+		goto err;
+
+	err = "Bad UUID";
+	if (bch_is_zero(sb->set_uuid, 16))
+		goto err;
+
+	err = "Bad cache device number in set";
+	if (!sb->nr_in_set ||
+	    sb->nr_in_set <= sb->nr_this_dev ||
+	    sb->nr_in_set > MAX_CACHES_PER_SET)
+		goto err;
+
+	err = "Journal buckets not sequential";
+	for (i = 0; i < sb->keys; i++)
+		if (sb->d[i] != sb->first_bucket + i)
+			goto err;
+
+	err = "Too many journal buckets";
+	if (sb->first_bucket + sb->keys > sb->nbuckets)
+		goto err;
+
+	err = "Invalid superblock: first bucket comes before end of super";
+	if (sb->first_bucket * sb->bucket_size < 16)
+		goto err;
+
+	err = NULL;
+err:
+	return err;
+}
+
+
 static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
 			      struct cache_sb_disk **res)
 {
@@ -84,7 +171,6 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
 	sb->flags		= le64_to_cpu(s->flags);
 	sb->seq			= le64_to_cpu(s->seq);
 	sb->last_mount		= le32_to_cpu(s->last_mount);
-	sb->first_bucket	= le16_to_cpu(s->first_bucket);
 	sb->keys		= le16_to_cpu(s->keys);
 
 	for (i = 0; i < SB_JOURNAL_BUCKETS; i++)
@@ -101,10 +187,6 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
 	if (memcmp(sb->magic, bcache_magic, 16))
 		goto err;
 
-	err = "Too many journal buckets";
-	if (sb->keys > SB_JOURNAL_BUCKETS)
-		goto err;
-
 	err = "Bad checksum";
 	if (s->csum != csum_set(s))
 		goto err;
@@ -124,6 +206,7 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
 		sb->data_offset	= BDEV_DATA_START_DEFAULT;
 		break;
 	case BCACHE_SB_VERSION_BDEV_WITH_OFFSET:
+	case BCACHE_SB_VERSION_BDEV_WITH_FEATURES:
 		sb->data_offset	= le64_to_cpu(s->data_offset);
 
 		err = "Bad data offset";
@@ -133,55 +216,21 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
 		break;
 	case BCACHE_SB_VERSION_CDEV:
 	case BCACHE_SB_VERSION_CDEV_WITH_UUID:
-		sb->nbuckets	= le64_to_cpu(s->nbuckets);
-		sb->bucket_size	= le16_to_cpu(s->bucket_size);
-
-		sb->nr_in_set	= le16_to_cpu(s->nr_in_set);
-		sb->nr_this_dev	= le16_to_cpu(s->nr_this_dev);
-
-		err = "Too many buckets";
-		if (sb->nbuckets > LONG_MAX)
-			goto err;
-
-		err = "Not enough buckets";
-		if (sb->nbuckets < 1 << 7)
-			goto err;
-
-		err = "Bad block/bucket size";
-		if (!is_power_of_2(sb->block_size) ||
-		    sb->block_size > PAGE_SECTORS ||
-		    !is_power_of_2(sb->bucket_size) ||
-		    sb->bucket_size < PAGE_SECTORS)
-			goto err;
-
-		err = "Invalid superblock: device too small";
-		if (get_capacity(bdev->bd_disk) <
-		    sb->bucket_size * sb->nbuckets)
-			goto err;
-
-		err = "Bad UUID";
-		if (bch_is_zero(sb->set_uuid, 16))
-			goto err;
-
-		err = "Bad cache device number in set";
-		if (!sb->nr_in_set ||
-		    sb->nr_in_set <= sb->nr_this_dev ||
-		    sb->nr_in_set > MAX_CACHES_PER_SET)
-			goto err;
-
-		err = "Journal buckets not sequential";
-		for (i = 0; i < sb->keys; i++)
-			if (sb->d[i] != sb->first_bucket + i)
-				goto err;
-
-		err = "Too many journal buckets";
-		if (sb->first_bucket + sb->keys > sb->nbuckets)
+		err = read_super_common(sb, bdev, s);
+		if (err)
 			goto err;
-
-		err = "Invalid superblock: first bucket comes before end of super";
-		if (sb->first_bucket * sb->bucket_size < 16)
+		break;
+	case BCACHE_SB_VERSION_CDEV_WITH_FEATURES:
+		/*
+		 * Feature bits are needed in read_super_common(),
+		 * convert them firstly.
+		 */
+		sb->feature_compat = le64_to_cpu(s->feature_compat);
+		sb->feature_incompat = le64_to_cpu(s->feature_incompat);
+		sb->feature_ro_compat = le64_to_cpu(s->feature_ro_compat);
+		err = read_super_common(sb, bdev, s);
+		if (err)
 			goto err;
-
 		break;
 	default:
 		err = "Unsupported superblock version";
@@ -217,7 +266,6 @@ static void __write_super(struct cache_sb *sb, struct cache_sb_disk *out,
 			offset_in_page(out));
 
 	out->offset		= cpu_to_le64(sb->offset);
-	out->version		= cpu_to_le64(sb->version);
 
 	memcpy(out->uuid,	sb->uuid, 16);
 	memcpy(out->set_uuid,	sb->set_uuid, 16);
@@ -233,6 +281,13 @@ static void __write_super(struct cache_sb *sb, struct cache_sb_disk *out,
 	for (i = 0; i < sb->keys; i++)
 		out->d[i] = cpu_to_le64(sb->d[i]);
 
+	if (sb->version >= BCACHE_SB_VERSION_CDEV_WITH_FEATURES) {
+		out->feature_compat    = cpu_to_le64(sb->feature_compat);
+		out->feature_incompat  = cpu_to_le64(sb->feature_incompat);
+		out->feature_ro_compat = cpu_to_le64(sb->feature_ro_compat);
+	}
+
+	out->version		= cpu_to_le64(sb->version);
 	out->csum = csum_set(out);
 
 	pr_debug("ver %llu, flags %llu, seq %llu\n",
@@ -289,17 +344,20 @@ void bcache_write_super(struct cache_set *c)
 {
 	struct closure *cl = &c->sb_write;
 	struct cache *ca;
-	unsigned int i;
+	unsigned int i, version = BCACHE_SB_VERSION_CDEV_WITH_UUID;
 
 	down(&c->sb_write_mutex);
 	closure_init(cl, &c->cl);
 
 	c->sb.seq++;
 
+	if (c->sb.version > version)
+		version = c->sb.version;
+
 	for_each_cache(ca, c, i) {
 		struct bio *bio = &ca->sb_bio;
 
-		ca->sb.version		= BCACHE_SB_VERSION_CDEV_WITH_UUID;
+		ca->sb.version		= version;
 		ca->sb.seq		= c->sb.seq;
 		ca->sb.last_mount	= c->sb.last_mount;
 
@@ -423,6 +481,7 @@ static int __uuid_write(struct cache_set *c)
 	BKEY_PADDED(key) k;
 	struct closure cl;
 	struct cache *ca;
+	unsigned int size;
 
 	closure_init_stack(&cl);
 	lockdep_assert_held(&bch_register_lock);
@@ -430,7 +489,8 @@ static int __uuid_write(struct cache_set *c)
 	if (bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, true))
 		return 1;
 
-	SET_KEY_SIZE(&k.key, c->sb.bucket_size);
+	size =  meta_bucket_pages(&c->sb) * PAGE_SECTORS;
+	SET_KEY_SIZE(&k.key, size);
 	uuid_io(c, REQ_OP_WRITE, 0, &k.key, &cl);
 	closure_sync(&cl);
 
@@ -518,7 +578,7 @@ static void prio_io(struct cache *ca, uint64_t bucket, int op,
 
 	bio->bi_iter.bi_sector	= bucket * ca->sb.bucket_size;
 	bio_set_dev(bio, ca->bdev);
-	bio->bi_iter.bi_size	= bucket_bytes(ca);
+	bio->bi_iter.bi_size	= meta_bucket_bytes(&ca->sb);
 
 	bio->bi_end_io	= prio_endio;
 	bio->bi_private = ca;
@@ -576,7 +636,7 @@ int bch_prio_write(struct cache *ca, bool wait)
 
 		p->next_bucket	= ca->prio_buckets[i + 1];
 		p->magic	= pset_magic(&ca->sb);
-		p->csum		= bch_crc64(&p->magic, bucket_bytes(ca) - 8);
+		p->csum		= bch_crc64(&p->magic, meta_bucket_bytes(&ca->sb) - 8);
 
 		bucket = bch_bucket_alloc(ca, RESERVE_PRIO, wait);
 		BUG_ON(bucket == -1);
@@ -629,7 +689,7 @@ static int prio_read(struct cache *ca, uint64_t bucket)
 			prio_io(ca, bucket, REQ_OP_READ, 0);
 
 			if (p->csum !=
-			    bch_crc64(&p->magic, bucket_bytes(ca) - 8)) {
+			    bch_crc64(&p->magic, meta_bucket_bytes(&ca->sb) - 8)) {
 				pr_warn("bad csum reading priorities\n");
 				goto out;
 			}
@@ -835,19 +895,19 @@ static int bcache_device_init(struct bcache_device *d, unsigned int block_size,
 	struct request_queue *q;
 	const size_t max_stripes = min_t(size_t, INT_MAX,
 					 SIZE_MAX / sizeof(atomic_t));
-	size_t n;
+	uint64_t n;
 	int idx;
 
 	if (!d->stripe_size)
 		d->stripe_size = 1 << 31;
 
-	d->nr_stripes = DIV_ROUND_UP_ULL(sectors, d->stripe_size);
-
-	if (!d->nr_stripes || d->nr_stripes > max_stripes) {
-		pr_err("nr_stripes too large or invalid: %u (start sector beyond end of disk?)\n",
-			(unsigned int)d->nr_stripes);
+	n = DIV_ROUND_UP_ULL(sectors, d->stripe_size);
+	if (!n || n > max_stripes) {
+		pr_err("nr_stripes too large or invalid: %llu (start sector beyond end of disk?)\n",
+			n);
 		return -ENOMEM;
 	}
+	d->nr_stripes = n;
 
 	n = d->nr_stripes * sizeof(atomic_t);
 	d->stripe_sectors_dirty = kvzalloc(n, GFP_KERNEL);
@@ -1620,7 +1680,7 @@ static void cache_set_free(struct closure *cl)
 		}
 
 	bch_bset_sort_state_free(&c->sort);
-	free_pages((unsigned long) c->uuids, ilog2(bucket_pages(c)));
+	free_pages((unsigned long) c->uuids, ilog2(meta_bucket_pages(&c->sb)));
 
 	if (c->moving_gc_wq)
 		destroy_workqueue(c->moving_gc_wq);
@@ -1783,7 +1843,10 @@ void bch_cache_set_unregister(struct cache_set *c)
 }
 
 #define alloc_bucket_pages(gfp, c)			\
-	((void *) __get_free_pages(__GFP_ZERO|gfp, ilog2(bucket_pages(c))))
+	((void *) __get_free_pages(__GFP_ZERO|__GFP_COMP|gfp, ilog2(bucket_pages(c))))
+
+#define alloc_meta_bucket_pages(gfp, sb)		\
+	((void *) __get_free_pages(__GFP_ZERO|__GFP_COMP|gfp, ilog2(meta_bucket_pages(sb))))
 
 struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
 {
@@ -1814,12 +1877,19 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
 	c->sb.bucket_size	= sb->bucket_size;
 	c->sb.nr_in_set		= sb->nr_in_set;
 	c->sb.last_mount	= sb->last_mount;
+	c->sb.version		= sb->version;
+	if (c->sb.version >= BCACHE_SB_VERSION_CDEV_WITH_FEATURES) {
+		c->sb.feature_compat = sb->feature_compat;
+		c->sb.feature_ro_compat = sb->feature_ro_compat;
+		c->sb.feature_incompat = sb->feature_incompat;
+	}
+
 	c->bucket_bits		= ilog2(sb->bucket_size);
 	c->block_bits		= ilog2(sb->block_size);
-	c->nr_uuids		= bucket_bytes(c) / sizeof(struct uuid_entry);
+	c->nr_uuids		= meta_bucket_bytes(&c->sb) / sizeof(struct uuid_entry);
 	c->devices_max_used	= 0;
 	atomic_set(&c->attached_dev_nr, 0);
-	c->btree_pages		= bucket_pages(c);
+	c->btree_pages		= meta_bucket_pages(&c->sb);
 	if (c->btree_pages > BTREE_MAX_PAGES)
 		c->btree_pages = max_t(int, c->btree_pages / 4,
 				       BTREE_MAX_PAGES);
@@ -1845,24 +1915,46 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
 	INIT_LIST_HEAD(&c->btree_cache_freed);
 	INIT_LIST_HEAD(&c->data_buckets);
 
-	iter_size = (sb->bucket_size / sb->block_size + 1) *
+	iter_size = ((meta_bucket_pages(sb) * PAGE_SECTORS) / sb->block_size + 1) *
 		sizeof(struct btree_iter_set);
 
-	if (!(c->devices = kcalloc(c->nr_uuids, sizeof(void *), GFP_KERNEL)) ||
-	    mempool_init_slab_pool(&c->search, 32, bch_search_cache) ||
-	    mempool_init_kmalloc_pool(&c->bio_meta, 2,
-				sizeof(struct bbio) + sizeof(struct bio_vec) *
-				bucket_pages(c)) ||
-	    mempool_init_kmalloc_pool(&c->fill_iter, 1, iter_size) ||
-	    bioset_init(&c->bio_split, 4, offsetof(struct bbio, bio),
-			BIOSET_NEED_BVECS|BIOSET_NEED_RESCUER) ||
-	    !(c->uuids = alloc_bucket_pages(GFP_KERNEL, c)) ||
-	    !(c->moving_gc_wq = alloc_workqueue("bcache_gc",
-						WQ_MEM_RECLAIM, 0)) ||
-	    bch_journal_alloc(c) ||
-	    bch_btree_cache_alloc(c) ||
-	    bch_open_buckets_alloc(c) ||
-	    bch_bset_sort_state_init(&c->sort, ilog2(c->btree_pages)))
+	c->devices = kcalloc(c->nr_uuids, sizeof(void *), GFP_KERNEL);
+	if (!c->devices)
+		goto err;
+
+	if (mempool_init_slab_pool(&c->search, 32, bch_search_cache))
+		goto err;
+
+	if (mempool_init_kmalloc_pool(&c->bio_meta, 2,
+			sizeof(struct bbio) +
+			sizeof(struct bio_vec) * meta_bucket_pages(&c->sb)))
+		goto err;
+
+	if (mempool_init_kmalloc_pool(&c->fill_iter, 1, iter_size))
+		goto err;
+
+	if (bioset_init(&c->bio_split, 4, offsetof(struct bbio, bio),
+			BIOSET_NEED_BVECS|BIOSET_NEED_RESCUER))
+		goto err;
+
+	c->uuids = alloc_meta_bucket_pages(GFP_KERNEL, &c->sb);
+	if (!c->uuids)
+		goto err;
+
+	c->moving_gc_wq = alloc_workqueue("bcache_gc", WQ_MEM_RECLAIM, 0);
+	if (!c->moving_gc_wq)
+		goto err;
+
+	if (bch_journal_alloc(c))
+		goto err;
+
+	if (bch_btree_cache_alloc(c))
+		goto err;
+
+	if (bch_open_buckets_alloc(c))
+		goto err;
+
+	if (bch_bset_sort_state_init(&c->sort, ilog2(c->btree_pages)))
 		goto err;
 
 	c->congested_read_threshold_us	= 2000;
@@ -2107,7 +2199,14 @@ found:
 	    sysfs_create_link(&c->kobj, &ca->kobj, buf))
 		goto err;
 
-	if (ca->sb.seq > c->sb.seq) {
+	/*
+	 * A special case is both ca->sb.seq and c->sb.seq are 0,
+	 * such condition happens on a new created cache device whose
+	 * super block is never flushed yet. In this case c->sb.version
+	 * and other members should be updated too, otherwise we will
+	 * have a mistaken super block version in cache set.
+	 */
+	if (ca->sb.seq > c->sb.seq || c->sb.seq == 0) {
 		c->sb.version		= ca->sb.version;
 		memcpy(c->sb.set_uuid, ca->sb.set_uuid, 16);
 		c->sb.flags             = ca->sb.flags;
@@ -2145,7 +2244,7 @@ void bch_cache_release(struct kobject *kobj)
 		ca->set->cache[ca->sb.nr_this_dev] = NULL;
 	}
 
-	free_pages((unsigned long) ca->disk_buckets, ilog2(bucket_pages(ca)));
+	free_pages((unsigned long) ca->disk_buckets, ilog2(meta_bucket_pages(&ca->sb)));
 	kfree(ca->prio_buckets);
 	vfree(ca->buckets);
 
@@ -2242,7 +2341,7 @@ static int cache_alloc(struct cache *ca)
 		goto err_prio_buckets_alloc;
 	}
 
-	ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca);
+	ca->disk_buckets = alloc_meta_bucket_pages(GFP_KERNEL, &ca->sb);
 	if (!ca->disk_buckets) {
 		err = "ca->disk_buckets alloc failed";
 		goto err_disk_buckets_alloc;
@@ -2789,7 +2888,7 @@ static int __init bcache_init(void)
 	static const struct attribute *files[] = {
 		&ksysfs_register.attr,
 		&ksysfs_register_quiet.attr,
-#ifdef CONFIG_BCACHE_ASYNC_REGISTRAION
+#ifdef CONFIG_BCACHE_ASYNC_REGISTRATION
 		&ksysfs_register_async.attr,
 #endif
 		&ksysfs_pendings_cleanup.attr,
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 0dadec5a78f6..ac06c0bc3c0a 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -11,6 +11,7 @@
 #include "btree.h"
 #include "request.h"
 #include "writeback.h"
+#include "features.h"
 
 #include <linux/blkdev.h>
 #include <linux/sort.h>
@@ -88,6 +89,9 @@ read_attribute(btree_used_percent);
 read_attribute(average_key_size);
 read_attribute(dirty_data);
 read_attribute(bset_tree_stats);
+read_attribute(feature_compat);
+read_attribute(feature_ro_compat);
+read_attribute(feature_incompat);
 
 read_attribute(state);
 read_attribute(cache_read_races);
@@ -779,6 +783,13 @@ SHOW(__bch_cache_set)
 	if (attr == &sysfs_bset_tree_stats)
 		return bch_bset_print_stats(c, buf);
 
+	if (attr == &sysfs_feature_compat)
+		return bch_print_cache_set_feature_compat(c, buf, PAGE_SIZE);
+	if (attr == &sysfs_feature_ro_compat)
+		return bch_print_cache_set_feature_ro_compat(c, buf, PAGE_SIZE);
+	if (attr == &sysfs_feature_incompat)
+		return bch_print_cache_set_feature_incompat(c, buf, PAGE_SIZE);
+
 	return 0;
 }
 SHOW_LOCKED(bch_cache_set)
@@ -987,6 +998,9 @@ static struct attribute *bch_cache_set_internal_files[] = {
 	&sysfs_io_disable,
 	&sysfs_cutoff_writeback,
 	&sysfs_cutoff_writeback_sync,
+	&sysfs_feature_compat,
+	&sysfs_feature_ro_compat,
+	&sysfs_feature_incompat,
 	NULL
 };
 KTYPE(bch_cache_set_internal);
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index 1cf1e5016cb9..4f4ad6b3d43a 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -459,10 +459,8 @@ static void read_dirty(struct cached_dev *dc)
 		for (i = 0; i < nk; i++) {
 			w = keys[i];
 
-			io = kzalloc(sizeof(struct dirty_io) +
-				     sizeof(struct bio_vec) *
-				     DIV_ROUND_UP(KEY_SIZE(&w->key),
-						  PAGE_SECTORS),
+			io = kzalloc(struct_size(io, bio.bi_inline_vecs,
+						DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS)),
 				     GFP_KERNEL);
 			if (!io)
 				goto err;
@@ -523,15 +521,19 @@ void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned int inode,
 				  uint64_t offset, int nr_sectors)
 {
 	struct bcache_device *d = c->devices[inode];
-	unsigned int stripe_offset, stripe, sectors_dirty;
+	unsigned int stripe_offset, sectors_dirty;
+	int stripe;
 
 	if (!d)
 		return;
 
+	stripe = offset_to_stripe(d, offset);
+	if (stripe < 0)
+		return;
+
 	if (UUID_FLASH_ONLY(&c->uuids[inode]))
 		atomic_long_add(nr_sectors, &c->flash_dev_dirty_sectors);
 
-	stripe = offset_to_stripe(d, offset);
 	stripe_offset = offset & (d->stripe_size - 1);
 
 	while (nr_sectors) {
@@ -571,12 +573,12 @@ static bool dirty_pred(struct keybuf *buf, struct bkey *k)
 static void refill_full_stripes(struct cached_dev *dc)
 {
 	struct keybuf *buf = &dc->writeback_keys;
-	unsigned int start_stripe, stripe, next_stripe;
+	unsigned int start_stripe, next_stripe;
+	int stripe;
 	bool wrapped = false;
 
 	stripe = offset_to_stripe(&dc->disk, KEY_OFFSET(&buf->last_scanned));
-
-	if (stripe >= dc->disk.nr_stripes)
+	if (stripe < 0)
 		stripe = 0;
 
 	start_stripe = stripe;
@@ -825,10 +827,8 @@ static int bch_dirty_init_thread(void *arg)
 	struct btree_iter iter;
 	struct bkey *k, *p;
 	int cur_idx, prev_idx, skip_nr;
-	int i;
 
 	k = p = NULL;
-	i = 0;
 	cur_idx = prev_idx = 0;
 
 	bch_btree_iter_init(&c->root->keys, &iter, NULL);
diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h
index b029843ce5b6..3f1230e22de0 100644
--- a/drivers/md/bcache/writeback.h
+++ b/drivers/md/bcache/writeback.h
@@ -52,10 +52,22 @@ static inline uint64_t bcache_dev_sectors_dirty(struct bcache_device *d)
 	return ret;
 }
 
-static inline unsigned int offset_to_stripe(struct bcache_device *d,
+static inline int offset_to_stripe(struct bcache_device *d,
 					uint64_t offset)
 {
 	do_div(offset, d->stripe_size);
+
+	/* d->nr_stripes is in range [1, INT_MAX] */
+	if (unlikely(offset >= d->nr_stripes)) {
+		pr_err("Invalid stripe %llu (>= nr_stripes %d).\n",
+			offset, d->nr_stripes);
+		return -EINVAL;
+	}
+
+	/*
+	 * Here offset is definitly smaller than INT_MAX,
+	 * return it as int will never overflow.
+	 */
 	return offset;
 }
 
@@ -63,7 +75,10 @@ static inline bool bcache_dev_stripe_dirty(struct cached_dev *dc,
 					   uint64_t offset,
 					   unsigned int nr_sectors)
 {
-	unsigned int stripe = offset_to_stripe(&dc->disk, offset);
+	int stripe = offset_to_stripe(&dc->disk, offset);
+
+	if (stripe < 0)
+		return false;
 
 	while (1) {
 		if (atomic_read(dc->disk.stripe_sectors_dirty + stripe))
diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 95a5f3757fa3..d61b524ae440 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -1631,7 +1631,7 @@ void md_bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector, bool force)
 		s += blocks;
 	}
 	bitmap->last_end_sync = jiffies;
-	sysfs_notify(&bitmap->mddev->kobj, NULL, "sync_completed");
+	sysfs_notify_dirent_safe(bitmap->mddev->sysfs_completed);
 }
 EXPORT_SYMBOL(md_bitmap_cond_end_sync);
 
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 813a99ffa86f..73fd50e77975 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -1518,6 +1518,7 @@ static void unlock_all_bitmaps(struct mddev *mddev)
 			}
 		}
 		kfree(cinfo->other_bitmap_lockres);
+		cinfo->other_bitmap_lockres = NULL;
 	}
 }
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 96b28f6d025c..153bc766bc5a 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -101,6 +101,8 @@ static void mddev_detach(struct mddev *mddev);
  * count by 2 for every hour elapsed between read errors.
  */
 #define MD_DEFAULT_MAX_CORRECTED_READ_ERRORS 20
+/* Default safemode delay: 200 msec */
+#define DEFAULT_SAFEMODE_DELAY ((200 * HZ)/1000 +1)
 /*
  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  * is 1000 KB/sec, so the extra system load does not show up that much.
@@ -463,24 +465,46 @@ check_suspended:
 }
 EXPORT_SYMBOL(md_handle_request);
 
+struct md_io {
+	struct mddev *mddev;
+	bio_end_io_t *orig_bi_end_io;
+	void *orig_bi_private;
+	unsigned long start_time;
+};
+
+static void md_end_io(struct bio *bio)
+{
+	struct md_io *md_io = bio->bi_private;
+	struct mddev *mddev = md_io->mddev;
+
+	disk_end_io_acct(mddev->gendisk, bio_op(bio), md_io->start_time);
+
+	bio->bi_end_io = md_io->orig_bi_end_io;
+	bio->bi_private = md_io->orig_bi_private;
+
+	mempool_free(md_io, &mddev->md_io_pool);
+
+	if (bio->bi_end_io)
+		bio->bi_end_io(bio);
+}
+
 static blk_qc_t md_submit_bio(struct bio *bio)
 {
 	const int rw = bio_data_dir(bio);
-	const int sgrp = op_stat_group(bio_op(bio));
 	struct mddev *mddev = bio->bi_disk->private_data;
-	unsigned int sectors;
 
-	if (unlikely(test_bit(MD_BROKEN, &mddev->flags)) && (rw == WRITE)) {
+	if (mddev == NULL || mddev->pers == NULL) {
 		bio_io_error(bio);
 		return BLK_QC_T_NONE;
 	}
 
-	blk_queue_split(&bio);
-
-	if (mddev == NULL || mddev->pers == NULL) {
+	if (unlikely(test_bit(MD_BROKEN, &mddev->flags)) && (rw == WRITE)) {
 		bio_io_error(bio);
 		return BLK_QC_T_NONE;
 	}
+
+	blk_queue_split(&bio);
+
 	if (mddev->ro == 1 && unlikely(rw == WRITE)) {
 		if (bio_sectors(bio) != 0)
 			bio->bi_status = BLK_STS_IOERR;
@@ -488,21 +512,27 @@ static blk_qc_t md_submit_bio(struct bio *bio)
 		return BLK_QC_T_NONE;
 	}
 
-	/*
-	 * save the sectors now since our bio can
-	 * go away inside make_request
-	 */
-	sectors = bio_sectors(bio);
+	if (bio->bi_end_io != md_end_io) {
+		struct md_io *md_io;
+
+		md_io = mempool_alloc(&mddev->md_io_pool, GFP_NOIO);
+		md_io->mddev = mddev;
+		md_io->orig_bi_end_io = bio->bi_end_io;
+		md_io->orig_bi_private = bio->bi_private;
+
+		bio->bi_end_io = md_end_io;
+		bio->bi_private = md_io;
+
+		md_io->start_time = disk_start_io_acct(mddev->gendisk,
+						       bio_sectors(bio),
+						       bio_op(bio));
+	}
+
 	/* bio could be mergeable after passing to underlayer */
 	bio->bi_opf &= ~REQ_NOMERGE;
 
 	md_handle_request(mddev, bio);
 
-	part_stat_lock();
-	part_stat_inc(&mddev->gendisk->part0, ios[sgrp]);
-	part_stat_add(&mddev->gendisk->part0, sectors[sgrp], sectors);
-	part_stat_unlock();
-
 	return BLK_QC_T_NONE;
 }
 
@@ -928,7 +958,8 @@ static void super_written(struct bio *bio)
 	struct mddev *mddev = rdev->mddev;
 
 	if (bio->bi_status) {
-		pr_err("md: super_written gets error=%d\n", bio->bi_status);
+		pr_err("md: %s gets error=%d\n", __func__,
+		       blk_status_to_errno(bio->bi_status));
 		md_error(mddev, rdev);
 		if (!test_bit(Faulty, &rdev->flags)
 		    && (bio->bi_opf & MD_FAILFAST)) {
@@ -2143,6 +2174,24 @@ retry:
 	sb->sb_csum = calc_sb_1_csum(sb);
 }
 
+static sector_t super_1_choose_bm_space(sector_t dev_size)
+{
+	sector_t bm_space;
+
+	/* if the device is bigger than 8Gig, save 64k for bitmap
+	 * usage, if bigger than 200Gig, save 128k
+	 */
+	if (dev_size < 64*2)
+		bm_space = 0;
+	else if (dev_size - 64*2 >= 200*1024*1024*2)
+		bm_space = 128*2;
+	else if (dev_size - 4*2 > 8*1024*1024*2)
+		bm_space = 64*2;
+	else
+		bm_space = 4*2;
+	return bm_space;
+}
+
 static unsigned long long
 super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
 {
@@ -2163,13 +2212,22 @@ super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
 		return 0;
 	} else {
 		/* minor version 0; superblock after data */
-		sector_t sb_start;
-		sb_start = (i_size_read(rdev->bdev->bd_inode) >> 9) - 8*2;
+		sector_t sb_start, bm_space;
+		sector_t dev_size = i_size_read(rdev->bdev->bd_inode) >> 9;
+
+		/* 8K is for superblock */
+		sb_start = dev_size - 8*2;
 		sb_start &= ~(sector_t)(4*2 - 1);
-		max_sectors = rdev->sectors + sb_start - rdev->sb_start;
+
+		bm_space = super_1_choose_bm_space(dev_size);
+
+		/* Space that can be used to store date needs to decrease
+		 * superblock bitmap space and bad block space(4K)
+		 */
+		max_sectors = sb_start - bm_space - 4*2;
+
 		if (!num_sectors || num_sectors > max_sectors)
 			num_sectors = max_sectors;
-		rdev->sb_start = sb_start;
 	}
 	sb = page_address(rdev->sb_page);
 	sb->data_size = cpu_to_le64(num_sectors);
@@ -2421,9 +2479,13 @@ static int bind_rdev_to_array(struct md_rdev *rdev, struct mddev *mddev)
 		goto fail;
 
 	ko = &part_to_dev(rdev->bdev->bd_part)->kobj;
-	if (sysfs_create_link(&rdev->kobj, ko, "block"))
-		/* failure here is OK */;
+	/* failure here is OK */
+	err = sysfs_create_link(&rdev->kobj, ko, "block");
 	rdev->sysfs_state = sysfs_get_dirent_safe(rdev->kobj.sd, "state");
+	rdev->sysfs_unack_badblocks =
+		sysfs_get_dirent_safe(rdev->kobj.sd, "unacknowledged_bad_blocks");
+	rdev->sysfs_badblocks =
+		sysfs_get_dirent_safe(rdev->kobj.sd, "bad_blocks");
 
 	list_add_rcu(&rdev->same_set, &mddev->disks);
 	bd_link_disk_holder(rdev->bdev, mddev->gendisk);
@@ -2457,7 +2519,11 @@ static void unbind_rdev_from_array(struct md_rdev *rdev)
 	rdev->mddev = NULL;
 	sysfs_remove_link(&rdev->kobj, "block");
 	sysfs_put(rdev->sysfs_state);
+	sysfs_put(rdev->sysfs_unack_badblocks);
+	sysfs_put(rdev->sysfs_badblocks);
 	rdev->sysfs_state = NULL;
+	rdev->sysfs_unack_badblocks = NULL;
+	rdev->sysfs_badblocks = NULL;
 	rdev->badblocks.count = 0;
 	/* We need to delay this, otherwise we can deadlock when
 	 * writing to 'remove' to "dev/state".  We also need
@@ -2802,7 +2868,7 @@ rewrite:
 		goto repeat;
 	wake_up(&mddev->sb_wait);
 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
-		sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+		sysfs_notify_dirent_safe(mddev->sysfs_completed);
 
 	rdev_for_each(rdev, mddev) {
 		if (test_and_clear_bit(FaultRecorded, &rdev->flags))
@@ -3182,8 +3248,8 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
 			return err;
 		} else
 			sysfs_notify_dirent_safe(rdev->sysfs_state);
-		if (sysfs_link_rdev(rdev->mddev, rdev))
-			/* failure here is OK */;
+		/* failure here is OK */;
+		sysfs_link_rdev(rdev->mddev, rdev);
 		/* don't wakeup anyone, leave that to userspace. */
 	} else {
 		if (slot >= rdev->mddev->raid_disks &&
@@ -4055,7 +4121,7 @@ level_store(struct mddev *mddev, const char *buf, size_t len)
 	mddev_resume(mddev);
 	if (!mddev->thread)
 		md_update_sb(mddev, 1);
-	sysfs_notify(&mddev->kobj, NULL, "level");
+	sysfs_notify_dirent_safe(mddev->sysfs_level);
 	md_new_event(mddev);
 	rv = len;
 out_unlock:
@@ -4168,6 +4234,14 @@ static struct md_sysfs_entry md_raid_disks =
 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
 
 static ssize_t
+uuid_show(struct mddev *mddev, char *page)
+{
+	return sprintf(page, "%pU\n", mddev->uuid);
+}
+static struct md_sysfs_entry md_uuid =
+__ATTR(uuid, S_IRUGO, uuid_show, NULL);
+
+static ssize_t
 chunk_size_show(struct mddev *mddev, char *page)
 {
 	if (mddev->reshape_position != MaxSector &&
@@ -4808,7 +4882,7 @@ action_store(struct mddev *mddev, const char *page, size_t len)
 		}
 		if (err)
 			return err;
-		sysfs_notify(&mddev->kobj, NULL, "degraded");
+		sysfs_notify_dirent_safe(mddev->sysfs_degraded);
 	} else {
 		if (cmd_match(page, "check"))
 			set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
@@ -5423,6 +5497,7 @@ static struct attribute *md_default_attrs[] = {
 	&md_level.attr,
 	&md_layout.attr,
 	&md_raid_disks.attr,
+	&md_uuid.attr,
 	&md_chunk_size.attr,
 	&md_size.attr,
 	&md_resync_start.attr,
@@ -5514,6 +5589,13 @@ static void md_free(struct kobject *ko)
 
 	if (mddev->sysfs_state)
 		sysfs_put(mddev->sysfs_state);
+	if (mddev->sysfs_completed)
+		sysfs_put(mddev->sysfs_completed);
+	if (mddev->sysfs_degraded)
+		sysfs_put(mddev->sysfs_degraded);
+	if (mddev->sysfs_level)
+		sysfs_put(mddev->sysfs_level);
+
 
 	if (mddev->gendisk)
 		del_gendisk(mddev->gendisk);
@@ -5525,6 +5607,7 @@ static void md_free(struct kobject *ko)
 
 	bioset_exit(&mddev->bio_set);
 	bioset_exit(&mddev->sync_set);
+	mempool_exit(&mddev->md_io_pool);
 	kfree(mddev);
 }
 
@@ -5620,6 +5703,11 @@ static int md_alloc(dev_t dev, char *name)
 		 */
 		mddev->hold_active = UNTIL_STOP;
 
+	error = mempool_init_kmalloc_pool(&mddev->md_io_pool, BIO_POOL_SIZE,
+					  sizeof(struct md_io));
+	if (error)
+		goto abort;
+
 	error = -ENOMEM;
 	mddev->queue = blk_alloc_queue(NUMA_NO_NODE);
 	if (!mddev->queue)
@@ -5676,6 +5764,9 @@ static int md_alloc(dev_t dev, char *name)
 	if (!error && mddev->kobj.sd) {
 		kobject_uevent(&mddev->kobj, KOBJ_ADD);
 		mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
+		mddev->sysfs_completed = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_completed");
+		mddev->sysfs_degraded = sysfs_get_dirent_safe(mddev->kobj.sd, "degraded");
+		mddev->sysfs_level = sysfs_get_dirent_safe(mddev->kobj.sd, "level");
 	}
 	mddev_put(mddev);
 	return error;
@@ -5961,7 +6052,7 @@ int md_run(struct mddev *mddev)
 	if (mddev_is_clustered(mddev))
 		mddev->safemode_delay = 0;
 	else
-		mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
+		mddev->safemode_delay = DEFAULT_SAFEMODE_DELAY;
 	mddev->in_sync = 1;
 	smp_wmb();
 	spin_lock(&mddev->lock);
@@ -6028,7 +6119,7 @@ static int do_md_run(struct mddev *mddev)
 	kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
 	sysfs_notify_dirent_safe(mddev->sysfs_state);
 	sysfs_notify_dirent_safe(mddev->sysfs_action);
-	sysfs_notify(&mddev->kobj, NULL, "degraded");
+	sysfs_notify_dirent_safe(mddev->sysfs_degraded);
 out:
 	clear_bit(MD_NOT_READY, &mddev->flags);
 	return err;
@@ -7339,6 +7430,8 @@ static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
 
 				mddev->bitmap_info.nodes = 0;
 				md_cluster_ops->leave(mddev);
+				module_put(md_cluster_mod);
+				mddev->safemode_delay = DEFAULT_SAFEMODE_DELAY;
 			}
 			mddev_suspend(mddev);
 			md_bitmap_destroy(mddev);
@@ -8330,6 +8423,7 @@ EXPORT_SYMBOL(unregister_md_cluster_operations);
 
 int md_setup_cluster(struct mddev *mddev, int nodes)
 {
+	int ret;
 	if (!md_cluster_ops)
 		request_module("md-cluster");
 	spin_lock(&pers_lock);
@@ -8341,7 +8435,10 @@ int md_setup_cluster(struct mddev *mddev, int nodes)
 	}
 	spin_unlock(&pers_lock);
 
-	return md_cluster_ops->join(mddev, nodes);
+	ret = md_cluster_ops->join(mddev, nodes);
+	if (!ret)
+		mddev->safemode_delay = 0;
+	return ret;
 }
 
 void md_cluster_stop(struct mddev *mddev)
@@ -8742,7 +8839,7 @@ void md_do_sync(struct md_thread *thread)
 	} else
 		mddev->curr_resync = 3; /* no longer delayed */
 	mddev->curr_resync_completed = j;
-	sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+	sysfs_notify_dirent_safe(mddev->sysfs_completed);
 	md_new_event(mddev);
 	update_time = jiffies;
 
@@ -8770,7 +8867,7 @@ void md_do_sync(struct md_thread *thread)
 				mddev->recovery_cp = j;
 			update_time = jiffies;
 			set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
-			sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+			sysfs_notify_dirent_safe(mddev->sysfs_completed);
 		}
 
 		while (j >= mddev->resync_max &&
@@ -8877,7 +8974,7 @@ void md_do_sync(struct md_thread *thread)
 	    !test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
 	    mddev->curr_resync > 3) {
 		mddev->curr_resync_completed = mddev->curr_resync;
-		sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+		sysfs_notify_dirent_safe(mddev->sysfs_completed);
 	}
 	mddev->pers->sync_request(mddev, max_sectors, &skipped);
 
@@ -9007,7 +9104,7 @@ static int remove_and_add_spares(struct mddev *mddev,
 	}
 
 	if (removed && mddev->kobj.sd)
-		sysfs_notify(&mddev->kobj, NULL, "degraded");
+		sysfs_notify_dirent_safe(mddev->sysfs_degraded);
 
 	if (this && removed)
 		goto no_add;
@@ -9035,8 +9132,8 @@ static int remove_and_add_spares(struct mddev *mddev,
 			rdev->recovery_offset = 0;
 		}
 		if (mddev->pers->hot_add_disk(mddev, rdev) == 0) {
-			if (sysfs_link_rdev(mddev, rdev))
-				/* failure here is OK */;
+			/* failure here is OK */
+			sysfs_link_rdev(mddev, rdev);
 			if (!test_bit(Journal, &rdev->flags))
 				spares++;
 			md_new_event(mddev);
@@ -9290,8 +9387,7 @@ void md_reap_sync_thread(struct mddev *mddev)
 		/* success...*/
 		/* activate any spares */
 		if (mddev->pers->spare_active(mddev)) {
-			sysfs_notify(&mddev->kobj, NULL,
-				     "degraded");
+			sysfs_notify_dirent_safe(mddev->sysfs_degraded);
 			set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
 		}
 	}
@@ -9381,8 +9477,7 @@ int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
 	if (rv == 0) {
 		/* Make sure they get written out promptly */
 		if (test_bit(ExternalBbl, &rdev->flags))
-			sysfs_notify(&rdev->kobj, NULL,
-				     "unacknowledged_bad_blocks");
+			sysfs_notify_dirent_safe(rdev->sysfs_unack_badblocks);
 		sysfs_notify_dirent_safe(rdev->sysfs_state);
 		set_mask_bits(&mddev->sb_flags, 0,
 			      BIT(MD_SB_CHANGE_CLEAN) | BIT(MD_SB_CHANGE_PENDING));
@@ -9403,7 +9498,7 @@ int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
 		s += rdev->data_offset;
 	rv = badblocks_clear(&rdev->badblocks, s, sectors);
 	if ((rv == 0) && test_bit(ExternalBbl, &rdev->flags))
-		sysfs_notify(&rdev->kobj, NULL, "bad_blocks");
+		sysfs_notify_dirent_safe(rdev->sysfs_badblocks);
 	return rv;
 }
 EXPORT_SYMBOL_GPL(rdev_clear_badblocks);
@@ -9633,7 +9728,7 @@ static int read_rdev(struct mddev *mddev, struct md_rdev *rdev)
 	if (rdev->recovery_offset == MaxSector &&
 	    !test_bit(In_sync, &rdev->flags) &&
 	    mddev->pers->spare_active(mddev))
-		sysfs_notify(&mddev->kobj, NULL, "degraded");
+		sysfs_notify_dirent_safe(mddev->sysfs_degraded);
 
 	put_page(swapout);
 	return 0;
diff --git a/drivers/md/md.h b/drivers/md/md.h
index e2f1ad9afc48..f79b5b4101ef 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -126,7 +126,10 @@ struct md_rdev {
 
 	struct kernfs_node *sysfs_state; /* handle for 'state'
 					   * sysfs entry */
-
+	/* handle for 'unacknowledged_bad_blocks' sysfs dentry */
+	struct kernfs_node *sysfs_unack_badblocks;
+	/* handle for 'bad_blocks' sysfs dentry */
+	struct kernfs_node *sysfs_badblocks;
 	struct badblocks badblocks;
 
 	struct {
@@ -420,6 +423,9 @@ struct mddev {
 							 * file in sysfs.
 							 */
 	struct kernfs_node		*sysfs_action;  /* handle for 'sync_action' */
+	struct kernfs_node		*sysfs_completed;	/*handle for 'sync_completed' */
+	struct kernfs_node		*sysfs_degraded;	/*handle for 'degraded' */
+	struct kernfs_node		*sysfs_level;		/*handle for 'level' */
 
 	struct work_struct del_work;	/* used for delayed sysfs removal */
 
@@ -481,6 +487,7 @@ struct mddev {
 	struct bio_set			sync_set; /* for sync operations like
 						   * metadata and bitmap writes
 						   */
+	mempool_t			md_io_pool;
 
 	/* Generic flush handling.
 	 * The last to finish preflush schedules a worker to submit
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 353288bc4cb7..e8fa32733917 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -955,6 +955,7 @@ static void wait_barrier(struct r10conf *conf)
 {
 	spin_lock_irq(&conf->resync_lock);
 	if (conf->barrier) {
+		struct bio_list *bio_list = current->bio_list;
 		conf->nr_waiting++;
 		/* Wait for the barrier to drop.
 		 * However if there are already pending
@@ -969,9 +970,16 @@ static void wait_barrier(struct r10conf *conf)
 		wait_event_lock_irq(conf->wait_barrier,
 				    !conf->barrier ||
 				    (atomic_read(&conf->nr_pending) &&
-				     current->bio_list &&
-				     (!bio_list_empty(&current->bio_list[0]) ||
-				      !bio_list_empty(&current->bio_list[1]))),
+				     bio_list &&
+				     (!bio_list_empty(&bio_list[0]) ||
+				      !bio_list_empty(&bio_list[1]))) ||
+				     /* move on if recovery thread is
+				      * blocked by us
+				      */
+				     (conf->mddev->thread->tsk == current &&
+				      test_bit(MD_RECOVERY_RUNNING,
+					       &conf->mddev->recovery) &&
+				      conf->nr_queued > 0),
 				    conf->resync_lock);
 		conf->nr_waiting--;
 		if (!conf->nr_waiting)
@@ -4282,8 +4290,8 @@ out:
 					else
 						rdev->recovery_offset = 0;
 
-					if (sysfs_link_rdev(mddev, rdev))
-						/* Failure here  is OK */;
+					/* Failure here is OK */
+					sysfs_link_rdev(mddev, rdev);
 				}
 			} else if (rdev->raid_disk >= conf->prev.raid_disks
 				   && !test_bit(Faulty, &rdev->flags)) {
@@ -4429,7 +4437,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr,
 			sector_nr = conf->reshape_progress;
 		if (sector_nr) {
 			mddev->curr_resync_completed = sector_nr;
-			sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+			sysfs_notify_dirent_safe(mddev->sysfs_completed);
 			*skipped = 1;
 			return sector_nr;
 		}
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 9b6da759dca2..4337ae0e6af2 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -195,9 +195,7 @@ struct r5l_log {
 static inline sector_t r5c_tree_index(struct r5conf *conf,
 				      sector_t sect)
 {
-	sector_t offset;
-
-	offset = sector_div(sect, conf->chunk_sectors);
+	sector_div(sect, conf->chunk_sectors);
 	return sect;
 }
 
@@ -298,8 +296,8 @@ r5c_return_dev_pending_writes(struct r5conf *conf, struct r5dev *dev)
 	wbi = dev->written;
 	dev->written = NULL;
 	while (wbi && wbi->bi_iter.bi_sector <
-	       dev->sector + STRIPE_SECTORS) {
-		wbi2 = r5_next_bio(wbi, dev->sector);
+	       dev->sector + RAID5_STRIPE_SECTORS(conf)) {
+		wbi2 = r5_next_bio(conf, wbi, dev->sector);
 		md_write_end(conf->mddev);
 		bio_endio(wbi);
 		wbi = wbi2;
@@ -316,7 +314,7 @@ void r5c_handle_cached_data_endio(struct r5conf *conf,
 			set_bit(R5_UPTODATE, &sh->dev[i].flags);
 			r5c_return_dev_pending_writes(conf, &sh->dev[i]);
 			md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
-					   STRIPE_SECTORS,
+					   RAID5_STRIPE_SECTORS(conf),
 					   !test_bit(STRIPE_DEGRADED, &sh->state),
 					   0);
 		}
@@ -364,7 +362,7 @@ void r5c_check_cached_full_stripe(struct r5conf *conf)
 	 */
 	if (atomic_read(&conf->r5c_cached_full_stripes) >=
 	    min(R5C_FULL_STRIPE_FLUSH_BATCH(conf),
-		conf->chunk_sectors >> STRIPE_SHIFT))
+		conf->chunk_sectors >> RAID5_STRIPE_SHIFT(conf)))
 		r5l_wake_reclaim(conf->log, 0);
 }
 
@@ -2430,10 +2428,15 @@ static void r5c_recovery_flush_data_only_stripes(struct r5l_log *log,
 	struct mddev *mddev = log->rdev->mddev;
 	struct r5conf *conf = mddev->private;
 	struct stripe_head *sh, *next;
+	bool cleared_pending = false;
 
 	if (ctx->data_only_stripes == 0)
 		return;
 
+	if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
+		cleared_pending = true;
+		clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
+	}
 	log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_BACK;
 
 	list_for_each_entry_safe(sh, next, &ctx->cached_list, lru) {
@@ -2448,6 +2451,8 @@ static void r5c_recovery_flush_data_only_stripes(struct r5l_log *log,
 		   atomic_read(&conf->active_stripes) == 0);
 
 	log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
+	if (cleared_pending)
+		set_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
 }
 
 static int r5l_recovery_log(struct r5l_log *log)
@@ -2532,13 +2537,10 @@ static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page)
 	struct r5conf *conf;
 	int ret;
 
-	ret = mddev_lock(mddev);
-	if (ret)
-		return ret;
-
+	spin_lock(&mddev->lock);
 	conf = mddev->private;
 	if (!conf || !conf->log) {
-		mddev_unlock(mddev);
+		spin_unlock(&mddev->lock);
 		return 0;
 	}
 
@@ -2558,7 +2560,7 @@ static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page)
 	default:
 		ret = 0;
 	}
-	mddev_unlock(mddev);
+	spin_unlock(&mddev->lock);
 	return ret;
 }
 
diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c
index a750f4bbb5d9..d0f540296fe9 100644
--- a/drivers/md/raid5-ppl.c
+++ b/drivers/md/raid5-ppl.c
@@ -324,7 +324,7 @@ static int ppl_log_stripe(struct ppl_log *log, struct stripe_head *sh)
 		 * be just after the last logged stripe and write to the same
 		 * disks. Use bit shift and logarithm to avoid 64-bit division.
 		 */
-		if ((sh->sector == sh_last->sector + STRIPE_SECTORS) &&
+		if ((sh->sector == sh_last->sector + RAID5_STRIPE_SECTORS(conf)) &&
 		    (data_sector >> ilog2(conf->chunk_sectors) ==
 		     data_sector_last >> ilog2(conf->chunk_sectors)) &&
 		    ((data_sector - data_sector_last) * data_disks ==
@@ -844,9 +844,9 @@ static int ppl_recover_entry(struct ppl_log *log, struct ppl_header_entry *e,
 
 	/* if start and end is 4k aligned, use a 4k block */
 	if (block_size == 512 &&
-	    (r_sector_first & (STRIPE_SECTORS - 1)) == 0 &&
-	    (r_sector_last & (STRIPE_SECTORS - 1)) == 0)
-		block_size = STRIPE_SIZE;
+	    (r_sector_first & (RAID5_STRIPE_SECTORS(conf) - 1)) == 0 &&
+	    (r_sector_last & (RAID5_STRIPE_SECTORS(conf) - 1)) == 0)
+		block_size = RAID5_STRIPE_SIZE(conf);
 
 	/* iterate through blocks in strip */
 	for (i = 0; i < strip_sectors; i += (block_size >> 9)) {
@@ -1274,7 +1274,8 @@ static int ppl_validate_rdev(struct md_rdev *rdev)
 	ppl_data_sectors = rdev->ppl.size - (PPL_HEADER_SIZE >> 9);
 
 	if (ppl_data_sectors > 0)
-		ppl_data_sectors = rounddown(ppl_data_sectors, STRIPE_SECTORS);
+		ppl_data_sectors = rounddown(ppl_data_sectors,
+				RAID5_STRIPE_SECTORS((struct r5conf *)rdev->mddev->private));
 
 	if (ppl_data_sectors <= 0) {
 		pr_warn("md/raid:%s: PPL space too small on %s\n",
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index aa6dd1381edf..fb8d1fb14088 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -69,13 +69,13 @@ static struct workqueue_struct *raid5_wq;
 
 static inline struct hlist_head *stripe_hash(struct r5conf *conf, sector_t sect)
 {
-	int hash = (sect >> STRIPE_SHIFT) & HASH_MASK;
+	int hash = (sect >> RAID5_STRIPE_SHIFT(conf)) & HASH_MASK;
 	return &conf->stripe_hashtbl[hash];
 }
 
-static inline int stripe_hash_locks_hash(sector_t sect)
+static inline int stripe_hash_locks_hash(struct r5conf *conf, sector_t sect)
 {
-	return (sect >> STRIPE_SHIFT) & STRIPE_HASH_LOCKS_MASK;
+	return (sect >> RAID5_STRIPE_SHIFT(conf)) & STRIPE_HASH_LOCKS_MASK;
 }
 
 static inline void lock_device_hash_lock(struct r5conf *conf, int hash)
@@ -627,7 +627,7 @@ raid5_get_active_stripe(struct r5conf *conf, sector_t sector,
 			int previous, int noblock, int noquiesce)
 {
 	struct stripe_head *sh;
-	int hash = stripe_hash_locks_hash(sector);
+	int hash = stripe_hash_locks_hash(conf, sector);
 	int inc_empty_inactive_list_flag;
 
 	pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector);
@@ -748,9 +748,9 @@ static void stripe_add_to_batch_list(struct r5conf *conf, struct stripe_head *sh
 	tmp_sec = sh->sector;
 	if (!sector_div(tmp_sec, conf->chunk_sectors))
 		return;
-	head_sector = sh->sector - STRIPE_SECTORS;
+	head_sector = sh->sector - RAID5_STRIPE_SECTORS(conf);
 
-	hash = stripe_hash_locks_hash(head_sector);
+	hash = stripe_hash_locks_hash(conf, head_sector);
 	spin_lock_irq(conf->hash_locks + hash);
 	head = __find_stripe(conf, head_sector, conf->generation);
 	if (head && !atomic_inc_not_zero(&head->count)) {
@@ -1057,7 +1057,7 @@ again:
 		       test_bit(WriteErrorSeen, &rdev->flags)) {
 			sector_t first_bad;
 			int bad_sectors;
-			int bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS,
+			int bad = is_badblock(rdev, sh->sector, RAID5_STRIPE_SECTORS(conf),
 					      &first_bad, &bad_sectors);
 			if (!bad)
 				break;
@@ -1089,7 +1089,7 @@ again:
 		if (rdev) {
 			if (s->syncing || s->expanding || s->expanded
 			    || s->replacing)
-				md_sync_acct(rdev->bdev, STRIPE_SECTORS);
+				md_sync_acct(rdev->bdev, RAID5_STRIPE_SECTORS(conf));
 
 			set_bit(STRIPE_IO_STARTED, &sh->state);
 
@@ -1129,9 +1129,9 @@ again:
 			else
 				sh->dev[i].vec.bv_page = sh->dev[i].page;
 			bi->bi_vcnt = 1;
-			bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
+			bi->bi_io_vec[0].bv_len = RAID5_STRIPE_SIZE(conf);
 			bi->bi_io_vec[0].bv_offset = 0;
-			bi->bi_iter.bi_size = STRIPE_SIZE;
+			bi->bi_iter.bi_size = RAID5_STRIPE_SIZE(conf);
 			bi->bi_write_hint = sh->dev[i].write_hint;
 			if (!rrdev)
 				sh->dev[i].write_hint = RWH_WRITE_LIFE_NOT_SET;
@@ -1156,7 +1156,7 @@ again:
 		if (rrdev) {
 			if (s->syncing || s->expanding || s->expanded
 			    || s->replacing)
-				md_sync_acct(rrdev->bdev, STRIPE_SECTORS);
+				md_sync_acct(rrdev->bdev, RAID5_STRIPE_SECTORS(conf));
 
 			set_bit(STRIPE_IO_STARTED, &sh->state);
 
@@ -1183,9 +1183,9 @@ again:
 				WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
 			sh->dev[i].rvec.bv_page = sh->dev[i].page;
 			rbi->bi_vcnt = 1;
-			rbi->bi_io_vec[0].bv_len = STRIPE_SIZE;
+			rbi->bi_io_vec[0].bv_len = RAID5_STRIPE_SIZE(conf);
 			rbi->bi_io_vec[0].bv_offset = 0;
-			rbi->bi_iter.bi_size = STRIPE_SIZE;
+			rbi->bi_iter.bi_size = RAID5_STRIPE_SIZE(conf);
 			rbi->bi_write_hint = sh->dev[i].write_hint;
 			sh->dev[i].write_hint = RWH_WRITE_LIFE_NOT_SET;
 			/*
@@ -1235,6 +1235,7 @@ async_copy_data(int frombio, struct bio *bio, struct page **page,
 	int page_offset;
 	struct async_submit_ctl submit;
 	enum async_tx_flags flags = 0;
+	struct r5conf *conf = sh->raid_conf;
 
 	if (bio->bi_iter.bi_sector >= sector)
 		page_offset = (signed)(bio->bi_iter.bi_sector - sector) * 512;
@@ -1256,8 +1257,8 @@ async_copy_data(int frombio, struct bio *bio, struct page **page,
 			len -= b_offset;
 		}
 
-		if (len > 0 && page_offset + len > STRIPE_SIZE)
-			clen = STRIPE_SIZE - page_offset;
+		if (len > 0 && page_offset + len > RAID5_STRIPE_SIZE(conf))
+			clen = RAID5_STRIPE_SIZE(conf) - page_offset;
 		else
 			clen = len;
 
@@ -1265,9 +1266,9 @@ async_copy_data(int frombio, struct bio *bio, struct page **page,
 			b_offset += bvl.bv_offset;
 			bio_page = bvl.bv_page;
 			if (frombio) {
-				if (sh->raid_conf->skip_copy &&
+				if (conf->skip_copy &&
 				    b_offset == 0 && page_offset == 0 &&
-				    clen == STRIPE_SIZE &&
+				    clen == RAID5_STRIPE_SIZE(conf) &&
 				    !no_skipcopy)
 					*page = bio_page;
 				else
@@ -1292,6 +1293,7 @@ static void ops_complete_biofill(void *stripe_head_ref)
 {
 	struct stripe_head *sh = stripe_head_ref;
 	int i;
+	struct r5conf *conf = sh->raid_conf;
 
 	pr_debug("%s: stripe %llu\n", __func__,
 		(unsigned long long)sh->sector);
@@ -1312,8 +1314,8 @@ static void ops_complete_biofill(void *stripe_head_ref)
 			rbi = dev->read;
 			dev->read = NULL;
 			while (rbi && rbi->bi_iter.bi_sector <
-				dev->sector + STRIPE_SECTORS) {
-				rbi2 = r5_next_bio(rbi, dev->sector);
+				dev->sector + RAID5_STRIPE_SECTORS(conf)) {
+				rbi2 = r5_next_bio(conf, rbi, dev->sector);
 				bio_endio(rbi);
 				rbi = rbi2;
 			}
@@ -1330,6 +1332,7 @@ static void ops_run_biofill(struct stripe_head *sh)
 	struct dma_async_tx_descriptor *tx = NULL;
 	struct async_submit_ctl submit;
 	int i;
+	struct r5conf *conf = sh->raid_conf;
 
 	BUG_ON(sh->batch_head);
 	pr_debug("%s: stripe %llu\n", __func__,
@@ -1344,10 +1347,10 @@ static void ops_run_biofill(struct stripe_head *sh)
 			dev->toread = NULL;
 			spin_unlock_irq(&sh->stripe_lock);
 			while (rbi && rbi->bi_iter.bi_sector <
-				dev->sector + STRIPE_SECTORS) {
+				dev->sector + RAID5_STRIPE_SECTORS(conf)) {
 				tx = async_copy_data(0, rbi, &dev->page,
 						     dev->sector, tx, sh, 0);
-				rbi = r5_next_bio(rbi, dev->sector);
+				rbi = r5_next_bio(conf, rbi, dev->sector);
 			}
 		}
 	}
@@ -1429,9 +1432,11 @@ ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu)
 	init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, NULL,
 			  ops_complete_compute, sh, to_addr_conv(sh, percpu, 0));
 	if (unlikely(count == 1))
-		tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
+		tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0,
+				RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 	else
-		tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
+		tx = async_xor(xor_dest, xor_srcs, 0, count,
+				RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 
 	return tx;
 }
@@ -1522,7 +1527,8 @@ ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu)
 		init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
 				  ops_complete_compute, sh,
 				  to_addr_conv(sh, percpu, 0));
-		tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
+		tx = async_gen_syndrome(blocks, 0, count+2,
+				RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 	} else {
 		/* Compute any data- or p-drive using XOR */
 		count = 0;
@@ -1535,7 +1541,8 @@ ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu)
 		init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
 				  NULL, ops_complete_compute, sh,
 				  to_addr_conv(sh, percpu, 0));
-		tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit);
+		tx = async_xor(dest, blocks, 0, count,
+				RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 	}
 
 	return tx;
@@ -1598,7 +1605,8 @@ ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
 					  ops_complete_compute, sh,
 					  to_addr_conv(sh, percpu, 0));
 			return async_gen_syndrome(blocks, 0, syndrome_disks+2,
-						  STRIPE_SIZE, &submit);
+						  RAID5_STRIPE_SIZE(sh->raid_conf),
+						  &submit);
 		} else {
 			struct page *dest;
 			int data_target;
@@ -1621,7 +1629,8 @@ ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
 					  ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
 					  NULL, NULL, NULL,
 					  to_addr_conv(sh, percpu, 0));
-			tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE,
+			tx = async_xor(dest, blocks, 0, count,
+				       RAID5_STRIPE_SIZE(sh->raid_conf),
 				       &submit);
 
 			count = set_syndrome_sources(blocks, sh, SYNDROME_SRC_ALL);
@@ -1629,7 +1638,8 @@ ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
 					  ops_complete_compute, sh,
 					  to_addr_conv(sh, percpu, 0));
 			return async_gen_syndrome(blocks, 0, count+2,
-						  STRIPE_SIZE, &submit);
+						  RAID5_STRIPE_SIZE(sh->raid_conf),
+						  &submit);
 		}
 	} else {
 		init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
@@ -1638,13 +1648,15 @@ ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
 		if (failb == syndrome_disks) {
 			/* We're missing D+P. */
 			return async_raid6_datap_recov(syndrome_disks+2,
-						       STRIPE_SIZE, faila,
-						       blocks, &submit);
+						RAID5_STRIPE_SIZE(sh->raid_conf),
+						faila,
+						blocks, &submit);
 		} else {
 			/* We're missing D+D. */
 			return async_raid6_2data_recov(syndrome_disks+2,
-						       STRIPE_SIZE, faila, failb,
-						       blocks, &submit);
+						RAID5_STRIPE_SIZE(sh->raid_conf),
+						faila, failb,
+						blocks, &submit);
 		}
 	}
 }
@@ -1691,7 +1703,8 @@ ops_run_prexor5(struct stripe_head *sh, struct raid5_percpu *percpu,
 
 	init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
 			  ops_complete_prexor, sh, to_addr_conv(sh, percpu, 0));
-	tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
+	tx = async_xor(xor_dest, xor_srcs, 0, count,
+			RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 
 	return tx;
 }
@@ -1711,7 +1724,8 @@ ops_run_prexor6(struct stripe_head *sh, struct raid5_percpu *percpu,
 
 	init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_PQ_XOR_DST, tx,
 			  ops_complete_prexor, sh, to_addr_conv(sh, percpu, 0));
-	tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE,  &submit);
+	tx = async_gen_syndrome(blocks, 0, count+2,
+			RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 
 	return tx;
 }
@@ -1752,7 +1766,7 @@ again:
 			WARN_ON(dev->page != dev->orig_page);
 
 			while (wbi && wbi->bi_iter.bi_sector <
-				dev->sector + STRIPE_SECTORS) {
+				dev->sector + RAID5_STRIPE_SECTORS(conf)) {
 				if (wbi->bi_opf & REQ_FUA)
 					set_bit(R5_WantFUA, &dev->flags);
 				if (wbi->bi_opf & REQ_SYNC)
@@ -1770,7 +1784,7 @@ again:
 						clear_bit(R5_OVERWRITE, &dev->flags);
 					}
 				}
-				wbi = r5_next_bio(wbi, dev->sector);
+				wbi = r5_next_bio(conf, wbi, dev->sector);
 			}
 
 			if (head_sh->batch_head) {
@@ -1910,9 +1924,11 @@ again:
 	}
 
 	if (unlikely(count == 1))
-		tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
+		tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0,
+				RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 	else
-		tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
+		tx = async_xor(xor_dest, xor_srcs, 0, count,
+				RAID5_STRIPE_SIZE(sh->raid_conf), &submit);
 	if (!last_stripe) {
 		j++;
 		sh = list_first_entry(&sh->batch_list, struct stripe_head,
@@ -1972,7 +1988,8 @@ again:
 	} else
 		init_async_submit(&submit, 0, tx, NULL, NULL,
 				  to_addr_conv(sh, percpu, j));
-	tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE,  &submit);
+	tx = async_gen_syndrome(blocks, 0, count+2,
+			RAID5_STRIPE_SIZE(sh->raid_conf),  &submit);
 	if (!last_stripe) {
 		j++;
 		sh = list_first_entry(&sh->batch_list, struct stripe_head,
@@ -2020,7 +2037,8 @@ static void ops_run_check_p(struct stripe_head *sh, struct raid5_percpu *percpu)
 
 	init_async_submit(&submit, 0, NULL, NULL, NULL,
 			  to_addr_conv(sh, percpu, 0));
-	tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
+	tx = async_xor_val(xor_dest, xor_srcs, 0, count,
+			   RAID5_STRIPE_SIZE(sh->raid_conf),
 			   &sh->ops.zero_sum_result, &submit);
 
 	atomic_inc(&sh->count);
@@ -2045,7 +2063,8 @@ static void ops_run_check_pq(struct stripe_head *sh, struct raid5_percpu *percpu
 	atomic_inc(&sh->count);
 	init_async_submit(&submit, ASYNC_TX_ACK, NULL, ops_complete_check,
 			  sh, to_addr_conv(sh, percpu, 0));
-	async_syndrome_val(srcs, 0, count+2, STRIPE_SIZE,
+	async_syndrome_val(srcs, 0, count+2,
+			   RAID5_STRIPE_SIZE(sh->raid_conf),
 			   &sh->ops.zero_sum_result, percpu->spare_page, &submit);
 }
 
@@ -2217,9 +2236,9 @@ static int grow_stripes(struct r5conf *conf, int num)
 /**
  * scribble_alloc - allocate percpu scribble buffer for required size
  *		    of the scribble region
- * @percpu - from for_each_present_cpu() of the caller
- * @num - total number of disks in the array
- * @cnt - scribble objs count for required size of the scribble region
+ * @percpu: from for_each_present_cpu() of the caller
+ * @num: total number of disks in the array
+ * @cnt: scribble objs count for required size of the scribble region
  *
  * The scribble buffer size must be enough to contain:
  * 1/ a struct page pointer for each device in the array +2
@@ -2275,7 +2294,7 @@ static int resize_chunks(struct r5conf *conf, int new_disks, int new_sectors)
 
 		percpu = per_cpu_ptr(conf->percpu, cpu);
 		err = scribble_alloc(percpu, new_disks,
-				     new_sectors / STRIPE_SECTORS);
+				     new_sectors / RAID5_STRIPE_SECTORS(conf));
 		if (err)
 			break;
 	}
@@ -2509,10 +2528,10 @@ static void raid5_end_read_request(struct bio * bi)
 			 */
 			pr_info_ratelimited(
 				"md/raid:%s: read error corrected (%lu sectors at %llu on %s)\n",
-				mdname(conf->mddev), STRIPE_SECTORS,
+				mdname(conf->mddev), RAID5_STRIPE_SECTORS(conf),
 				(unsigned long long)s,
 				bdevname(rdev->bdev, b));
-			atomic_add(STRIPE_SECTORS, &rdev->corrected_errors);
+			atomic_add(RAID5_STRIPE_SECTORS(conf), &rdev->corrected_errors);
 			clear_bit(R5_ReadError, &sh->dev[i].flags);
 			clear_bit(R5_ReWrite, &sh->dev[i].flags);
 		} else if (test_bit(R5_ReadNoMerge, &sh->dev[i].flags))
@@ -2585,7 +2604,7 @@ static void raid5_end_read_request(struct bio * bi)
 			if (!(set_bad
 			      && test_bit(In_sync, &rdev->flags)
 			      && rdev_set_badblocks(
-				      rdev, sh->sector, STRIPE_SECTORS, 0)))
+				      rdev, sh->sector, RAID5_STRIPE_SECTORS(conf), 0)))
 				md_error(conf->mddev, rdev);
 		}
 	}
@@ -2637,7 +2656,7 @@ static void raid5_end_write_request(struct bio *bi)
 		if (bi->bi_status)
 			md_error(conf->mddev, rdev);
 		else if (is_badblock(rdev, sh->sector,
-				     STRIPE_SECTORS,
+				     RAID5_STRIPE_SECTORS(conf),
 				     &first_bad, &bad_sectors))
 			set_bit(R5_MadeGoodRepl, &sh->dev[i].flags);
 	} else {
@@ -2649,7 +2668,7 @@ static void raid5_end_write_request(struct bio *bi)
 				set_bit(MD_RECOVERY_NEEDED,
 					&rdev->mddev->recovery);
 		} else if (is_badblock(rdev, sh->sector,
-				       STRIPE_SECTORS,
+				       RAID5_STRIPE_SECTORS(conf),
 				       &first_bad, &bad_sectors)) {
 			set_bit(R5_MadeGood, &sh->dev[i].flags);
 			if (test_bit(R5_ReadError, &sh->dev[i].flags))
@@ -3283,13 +3302,13 @@ static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx,
 		/* check if page is covered */
 		sector_t sector = sh->dev[dd_idx].sector;
 		for (bi=sh->dev[dd_idx].towrite;
-		     sector < sh->dev[dd_idx].sector + STRIPE_SECTORS &&
+		     sector < sh->dev[dd_idx].sector + RAID5_STRIPE_SECTORS(conf) &&
 			     bi && bi->bi_iter.bi_sector <= sector;
-		     bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) {
+		     bi = r5_next_bio(conf, bi, sh->dev[dd_idx].sector)) {
 			if (bio_end_sector(bi) >= sector)
 				sector = bio_end_sector(bi);
 		}
-		if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS)
+		if (sector >= sh->dev[dd_idx].sector + RAID5_STRIPE_SECTORS(conf))
 			if (!test_and_set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags))
 				sh->overwrite_disks++;
 	}
@@ -3314,7 +3333,7 @@ static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx,
 		set_bit(STRIPE_BITMAP_PENDING, &sh->state);
 		spin_unlock_irq(&sh->stripe_lock);
 		md_bitmap_startwrite(conf->mddev->bitmap, sh->sector,
-				     STRIPE_SECTORS, 0);
+				     RAID5_STRIPE_SECTORS(conf), 0);
 		spin_lock_irq(&sh->stripe_lock);
 		clear_bit(STRIPE_BITMAP_PENDING, &sh->state);
 		if (!sh->batch_head) {
@@ -3376,7 +3395,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 				if (!rdev_set_badblocks(
 					    rdev,
 					    sh->sector,
-					    STRIPE_SECTORS, 0))
+					    RAID5_STRIPE_SECTORS(conf), 0))
 					md_error(conf->mddev, rdev);
 				rdev_dec_pending(rdev, conf->mddev);
 			}
@@ -3396,8 +3415,8 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 			wake_up(&conf->wait_for_overlap);
 
 		while (bi && bi->bi_iter.bi_sector <
-			sh->dev[i].sector + STRIPE_SECTORS) {
-			struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector);
+			sh->dev[i].sector + RAID5_STRIPE_SECTORS(conf)) {
+			struct bio *nextbi = r5_next_bio(conf, bi, sh->dev[i].sector);
 
 			md_write_end(conf->mddev);
 			bio_io_error(bi);
@@ -3405,7 +3424,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 		}
 		if (bitmap_end)
 			md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
-					   STRIPE_SECTORS, 0, 0);
+					   RAID5_STRIPE_SECTORS(conf), 0, 0);
 		bitmap_end = 0;
 		/* and fail all 'written' */
 		bi = sh->dev[i].written;
@@ -3417,8 +3436,8 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 
 		if (bi) bitmap_end = 1;
 		while (bi && bi->bi_iter.bi_sector <
-		       sh->dev[i].sector + STRIPE_SECTORS) {
-			struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector);
+		       sh->dev[i].sector + RAID5_STRIPE_SECTORS(conf)) {
+			struct bio *bi2 = r5_next_bio(conf, bi, sh->dev[i].sector);
 
 			md_write_end(conf->mddev);
 			bio_io_error(bi);
@@ -3441,9 +3460,9 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 			if (bi)
 				s->to_read--;
 			while (bi && bi->bi_iter.bi_sector <
-			       sh->dev[i].sector + STRIPE_SECTORS) {
+			       sh->dev[i].sector + RAID5_STRIPE_SECTORS(conf)) {
 				struct bio *nextbi =
-					r5_next_bio(bi, sh->dev[i].sector);
+					r5_next_bio(conf, bi, sh->dev[i].sector);
 
 				bio_io_error(bi);
 				bi = nextbi;
@@ -3451,7 +3470,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 		}
 		if (bitmap_end)
 			md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
-					   STRIPE_SECTORS, 0, 0);
+					   RAID5_STRIPE_SECTORS(conf), 0, 0);
 		/* If we were in the middle of a write the parity block might
 		 * still be locked - so just clear all R5_LOCKED flags
 		 */
@@ -3496,14 +3515,14 @@ handle_failed_sync(struct r5conf *conf, struct stripe_head *sh,
 			    && !test_bit(Faulty, &rdev->flags)
 			    && !test_bit(In_sync, &rdev->flags)
 			    && !rdev_set_badblocks(rdev, sh->sector,
-						   STRIPE_SECTORS, 0))
+						   RAID5_STRIPE_SECTORS(conf), 0))
 				abort = 1;
 			rdev = rcu_dereference(conf->disks[i].replacement);
 			if (rdev
 			    && !test_bit(Faulty, &rdev->flags)
 			    && !test_bit(In_sync, &rdev->flags)
 			    && !rdev_set_badblocks(rdev, sh->sector,
-						   STRIPE_SECTORS, 0))
+						   RAID5_STRIPE_SECTORS(conf), 0))
 				abort = 1;
 		}
 		rcu_read_unlock();
@@ -3511,7 +3530,7 @@ handle_failed_sync(struct r5conf *conf, struct stripe_head *sh,
 			conf->recovery_disabled =
 				conf->mddev->recovery_disabled;
 	}
-	md_done_sync(conf->mddev, STRIPE_SECTORS, !abort);
+	md_done_sync(conf->mddev, RAID5_STRIPE_SECTORS(conf), !abort);
 }
 
 static int want_replace(struct stripe_head *sh, int disk_idx)
@@ -3538,6 +3557,7 @@ static int need_this_block(struct stripe_head *sh, struct stripe_head_state *s,
 	struct r5dev *fdev[2] = { &sh->dev[s->failed_num[0]],
 				  &sh->dev[s->failed_num[1]] };
 	int i;
+	bool force_rcw = (sh->raid_conf->rmw_level == PARITY_DISABLE_RMW);
 
 
 	if (test_bit(R5_LOCKED, &dev->flags) ||
@@ -3596,17 +3616,27 @@ static int need_this_block(struct stripe_head *sh, struct stripe_head_state *s,
 			 * devices must be read.
 			 */
 			return 1;
+
+		if (s->failed >= 2 &&
+		    (fdev[i]->towrite ||
+		     s->failed_num[i] == sh->pd_idx ||
+		     s->failed_num[i] == sh->qd_idx) &&
+		    !test_bit(R5_UPTODATE, &fdev[i]->flags))
+			/* In max degraded raid6, If the failed disk is P, Q,
+			 * or we want to read the failed disk, we need to do
+			 * reconstruct-write.
+			 */
+			force_rcw = true;
 	}
 
-	/* If we are forced to do a reconstruct-write, either because
-	 * the current RAID6 implementation only supports that, or
-	 * because parity cannot be trusted and we are currently
-	 * recovering it, there is extra need to be careful.
+	/* If we are forced to do a reconstruct-write, because parity
+	 * cannot be trusted and we are currently recovering it, there
+	 * is extra need to be careful.
 	 * If one of the devices that we would need to read, because
 	 * it is not being overwritten (and maybe not written at all)
 	 * is missing/faulty, then we need to read everything we can.
 	 */
-	if (sh->raid_conf->level != 6 &&
+	if (!force_rcw &&
 	    sh->sector < sh->raid_conf->mddev->recovery_cp)
 		/* reconstruct-write isn't being forced */
 		return 0;
@@ -3710,7 +3740,7 @@ static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s,
 	return 0;
 }
 
-/**
+/*
  * handle_stripe_fill - read or compute data to satisfy pending requests.
  */
 static void handle_stripe_fill(struct stripe_head *sh,
@@ -3785,14 +3815,14 @@ returnbi:
 				wbi = dev->written;
 				dev->written = NULL;
 				while (wbi && wbi->bi_iter.bi_sector <
-					dev->sector + STRIPE_SECTORS) {
-					wbi2 = r5_next_bio(wbi, dev->sector);
+					dev->sector + RAID5_STRIPE_SECTORS(conf)) {
+					wbi2 = r5_next_bio(conf, wbi, dev->sector);
 					md_write_end(conf->mddev);
 					bio_endio(wbi);
 					wbi = wbi2;
 				}
 				md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
-						   STRIPE_SECTORS,
+						   RAID5_STRIPE_SECTORS(conf),
 						   !test_bit(STRIPE_DEGRADED, &sh->state),
 						   0);
 				if (head_sh->batch_head) {
@@ -3976,10 +4006,8 @@ static int handle_stripe_dirtying(struct r5conf *conf,
 					set_bit(R5_LOCKED, &dev->flags);
 					set_bit(R5_Wantread, &dev->flags);
 					s->locked++;
-				} else {
+				} else
 					set_bit(STRIPE_DELAYED, &sh->state);
-					set_bit(STRIPE_HANDLE, &sh->state);
-				}
 			}
 		}
 	}
@@ -4004,10 +4032,8 @@ static int handle_stripe_dirtying(struct r5conf *conf,
 					set_bit(R5_Wantread, &dev->flags);
 					s->locked++;
 					qread++;
-				} else {
+				} else
 					set_bit(STRIPE_DELAYED, &sh->state);
-					set_bit(STRIPE_HANDLE, &sh->state);
-				}
 			}
 		}
 		if (rcw && conf->mddev->queue)
@@ -4099,7 +4125,7 @@ static void handle_parity_checks5(struct r5conf *conf, struct stripe_head *sh,
 			 */
 			set_bit(STRIPE_INSYNC, &sh->state);
 		else {
-			atomic64_add(STRIPE_SECTORS, &conf->mddev->resync_mismatches);
+			atomic64_add(RAID5_STRIPE_SECTORS(conf), &conf->mddev->resync_mismatches);
 			if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) {
 				/* don't try to repair!! */
 				set_bit(STRIPE_INSYNC, &sh->state);
@@ -4107,7 +4133,7 @@ static void handle_parity_checks5(struct r5conf *conf, struct stripe_head *sh,
 						    "%llu-%llu\n", mdname(conf->mddev),
 						    (unsigned long long) sh->sector,
 						    (unsigned long long) sh->sector +
-						    STRIPE_SECTORS);
+						    RAID5_STRIPE_SECTORS(conf));
 			} else {
 				sh->check_state = check_state_compute_run;
 				set_bit(STRIPE_COMPUTE_RUN, &sh->state);
@@ -4264,7 +4290,7 @@ static void handle_parity_checks6(struct r5conf *conf, struct stripe_head *sh,
 				 */
 			}
 		} else {
-			atomic64_add(STRIPE_SECTORS, &conf->mddev->resync_mismatches);
+			atomic64_add(RAID5_STRIPE_SECTORS(conf), &conf->mddev->resync_mismatches);
 			if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) {
 				/* don't try to repair!! */
 				set_bit(STRIPE_INSYNC, &sh->state);
@@ -4272,7 +4298,7 @@ static void handle_parity_checks6(struct r5conf *conf, struct stripe_head *sh,
 						    "%llu-%llu\n", mdname(conf->mddev),
 						    (unsigned long long) sh->sector,
 						    (unsigned long long) sh->sector +
-						    STRIPE_SECTORS);
+						    RAID5_STRIPE_SECTORS(conf));
 			} else {
 				int *target = &sh->ops.target;
 
@@ -4343,7 +4369,7 @@ static void handle_stripe_expansion(struct r5conf *conf, struct stripe_head *sh)
 			/* place all the copies on one channel */
 			init_async_submit(&submit, 0, tx, NULL, NULL, NULL);
 			tx = async_memcpy(sh2->dev[dd_idx].page,
-					  sh->dev[i].page, 0, 0, STRIPE_SIZE,
+					  sh->dev[i].page, 0, 0, RAID5_STRIPE_SIZE(conf),
 					  &submit);
 
 			set_bit(R5_Expanded, &sh2->dev[dd_idx].flags);
@@ -4442,8 +4468,8 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
 		 */
 		rdev = rcu_dereference(conf->disks[i].replacement);
 		if (rdev && !test_bit(Faulty, &rdev->flags) &&
-		    rdev->recovery_offset >= sh->sector + STRIPE_SECTORS &&
-		    !is_badblock(rdev, sh->sector, STRIPE_SECTORS,
+		    rdev->recovery_offset >= sh->sector + RAID5_STRIPE_SECTORS(conf) &&
+		    !is_badblock(rdev, sh->sector, RAID5_STRIPE_SECTORS(conf),
 				 &first_bad, &bad_sectors))
 			set_bit(R5_ReadRepl, &dev->flags);
 		else {
@@ -4457,7 +4483,7 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
 		if (rdev && test_bit(Faulty, &rdev->flags))
 			rdev = NULL;
 		if (rdev) {
-			is_bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS,
+			is_bad = is_badblock(rdev, sh->sector, RAID5_STRIPE_SECTORS(conf),
 					     &first_bad, &bad_sectors);
 			if (s->blocked_rdev == NULL
 			    && (test_bit(Blocked, &rdev->flags)
@@ -4484,7 +4510,7 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
 			}
 		} else if (test_bit(In_sync, &rdev->flags))
 			set_bit(R5_Insync, &dev->flags);
-		else if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset)
+		else if (sh->sector + RAID5_STRIPE_SECTORS(conf) <= rdev->recovery_offset)
 			/* in sync if before recovery_offset */
 			set_bit(R5_Insync, &dev->flags);
 		else if (test_bit(R5_UPTODATE, &dev->flags) &&
@@ -4573,12 +4599,12 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
 	rcu_read_unlock();
 }
 
+/*
+ * Return '1' if this is a member of batch, or '0' if it is a lone stripe or
+ * a head which can now be handled.
+ */
 static int clear_batch_ready(struct stripe_head *sh)
 {
-	/* Return '1' if this is a member of batch, or
-	 * '0' if it is a lone stripe or a head which can now be
-	 * handled.
-	 */
 	struct stripe_head *tmp;
 	if (!test_and_clear_bit(STRIPE_BATCH_READY, &sh->state))
 		return (sh->batch_head && sh->batch_head != sh);
@@ -4682,6 +4708,16 @@ static void handle_stripe(struct stripe_head *sh)
 	struct r5dev *pdev, *qdev;
 
 	clear_bit(STRIPE_HANDLE, &sh->state);
+
+	/*
+	 * handle_stripe should not continue handle the batched stripe, only
+	 * the head of batch list or lone stripe can continue. Otherwise we
+	 * could see break_stripe_batch_list warns about the STRIPE_ACTIVE
+	 * is set for the batched stripe.
+	 */
+	if (clear_batch_ready(sh))
+		return;
+
 	if (test_and_set_bit_lock(STRIPE_ACTIVE, &sh->state)) {
 		/* already being handled, ensure it gets handled
 		 * again when current action finishes */
@@ -4689,11 +4725,6 @@ static void handle_stripe(struct stripe_head *sh)
 		return;
 	}
 
-	if (clear_batch_ready(sh) ) {
-		clear_bit_unlock(STRIPE_ACTIVE, &sh->state);
-		return;
-	}
-
 	if (test_and_clear_bit(STRIPE_BATCH_ERR, &sh->state))
 		break_stripe_batch_list(sh, 0);
 
@@ -4842,7 +4873,7 @@ static void handle_stripe(struct stripe_head *sh)
 	 * or to load a block that is being partially written.
 	 */
 	if (s.to_read || s.non_overwrite
-	    || (conf->level == 6 && s.to_write && s.failed)
+	    || (s.to_write && s.failed)
 	    || (s.syncing && (s.uptodate + s.compute < disks))
 	    || s.replacing
 	    || s.expanding)
@@ -4927,7 +4958,7 @@ static void handle_stripe(struct stripe_head *sh)
 	if ((s.syncing || s.replacing) && s.locked == 0 &&
 	    !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
 	    test_bit(STRIPE_INSYNC, &sh->state)) {
-		md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
+		md_done_sync(conf->mddev, RAID5_STRIPE_SECTORS(conf), 1);
 		clear_bit(STRIPE_SYNCING, &sh->state);
 		if (test_and_clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags))
 			wake_up(&conf->wait_for_overlap);
@@ -4946,14 +4977,11 @@ static void handle_stripe(struct stripe_head *sh)
 				if (!test_bit(R5_ReWrite, &dev->flags)) {
 					set_bit(R5_Wantwrite, &dev->flags);
 					set_bit(R5_ReWrite, &dev->flags);
-					set_bit(R5_LOCKED, &dev->flags);
-					s.locked++;
-				} else {
+				} else
 					/* let's read it back */
 					set_bit(R5_Wantread, &dev->flags);
-					set_bit(R5_LOCKED, &dev->flags);
-					s.locked++;
-				}
+				set_bit(R5_LOCKED, &dev->flags);
+				s.locked++;
 			}
 		}
 
@@ -4995,7 +5023,7 @@ static void handle_stripe(struct stripe_head *sh)
 		clear_bit(STRIPE_EXPAND_READY, &sh->state);
 		atomic_dec(&conf->reshape_stripes);
 		wake_up(&conf->wait_for_overlap);
-		md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
+		md_done_sync(conf->mddev, RAID5_STRIPE_SECTORS(conf), 1);
 	}
 
 	if (s.expanding && s.locked == 0 &&
@@ -5025,14 +5053,14 @@ finish:
 				/* We own a safe reference to the rdev */
 				rdev = conf->disks[i].rdev;
 				if (!rdev_set_badblocks(rdev, sh->sector,
-							STRIPE_SECTORS, 0))
+							RAID5_STRIPE_SECTORS(conf), 0))
 					md_error(conf->mddev, rdev);
 				rdev_dec_pending(rdev, conf->mddev);
 			}
 			if (test_and_clear_bit(R5_MadeGood, &dev->flags)) {
 				rdev = conf->disks[i].rdev;
 				rdev_clear_badblocks(rdev, sh->sector,
-						     STRIPE_SECTORS, 0);
+						     RAID5_STRIPE_SECTORS(conf), 0);
 				rdev_dec_pending(rdev, conf->mddev);
 			}
 			if (test_and_clear_bit(R5_MadeGoodRepl, &dev->flags)) {
@@ -5041,7 +5069,7 @@ finish:
 					/* rdev have been moved down */
 					rdev = conf->disks[i].rdev;
 				rdev_clear_badblocks(rdev, sh->sector,
-						     STRIPE_SECTORS, 0);
+						     RAID5_STRIPE_SECTORS(conf), 0);
 				rdev_dec_pending(rdev, conf->mddev);
 			}
 		}
@@ -5483,7 +5511,7 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi)
 		/* Skip discard while reshape is happening */
 		return;
 
-	logical_sector = bi->bi_iter.bi_sector & ~((sector_t)STRIPE_SECTORS-1);
+	logical_sector = bi->bi_iter.bi_sector & ~((sector_t)RAID5_STRIPE_SECTORS(conf)-1);
 	last_sector = bio_end_sector(bi);
 
 	bi->bi_next = NULL;
@@ -5498,7 +5526,7 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi)
 	last_sector *= conf->chunk_sectors;
 
 	for (; logical_sector < last_sector;
-	     logical_sector += STRIPE_SECTORS) {
+	     logical_sector += RAID5_STRIPE_SECTORS(conf)) {
 		DEFINE_WAIT(w);
 		int d;
 	again:
@@ -5543,7 +5571,7 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi)
 			     d++)
 				md_bitmap_startwrite(mddev->bitmap,
 						     sh->sector,
-						     STRIPE_SECTORS,
+						     RAID5_STRIPE_SECTORS(conf),
 						     0);
 			sh->bm_seq = conf->seq_flush + 1;
 			set_bit(STRIPE_BIT_DELAY, &sh->state);
@@ -5608,12 +5636,12 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 		return true;
 	}
 
-	logical_sector = bi->bi_iter.bi_sector & ~((sector_t)STRIPE_SECTORS-1);
+	logical_sector = bi->bi_iter.bi_sector & ~((sector_t)RAID5_STRIPE_SECTORS(conf)-1);
 	last_sector = bio_end_sector(bi);
 	bi->bi_next = NULL;
 
 	prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE);
-	for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) {
+	for (; logical_sector < last_sector; logical_sector += RAID5_STRIPE_SECTORS(conf)) {
 		int previous;
 		int seq;
 
@@ -5711,8 +5739,7 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 				do_flush = false;
 			}
 
-			if (!sh->batch_head || sh == sh->batch_head)
-				set_bit(STRIPE_HANDLE, &sh->state);
+			set_bit(STRIPE_HANDLE, &sh->state);
 			clear_bit(STRIPE_DELAYED, &sh->state);
 			if ((!sh->batch_head || sh == sh->batch_head) &&
 			    (bi->bi_opf & REQ_SYNC) &&
@@ -5777,7 +5804,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
 		sector_div(sector_nr, new_data_disks);
 		if (sector_nr) {
 			mddev->curr_resync_completed = sector_nr;
-			sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+			sysfs_notify_dirent_safe(mddev->sysfs_completed);
 			*skipped = 1;
 			retn = sector_nr;
 			goto finish;
@@ -5891,11 +5918,11 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
 		conf->reshape_safe = mddev->reshape_position;
 		spin_unlock_irq(&conf->device_lock);
 		wake_up(&conf->wait_for_overlap);
-		sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+		sysfs_notify_dirent_safe(mddev->sysfs_completed);
 	}
 
 	INIT_LIST_HEAD(&stripes);
-	for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) {
+	for (i = 0; i < reshape_sectors; i += RAID5_STRIPE_SECTORS(conf)) {
 		int j;
 		int skipped_disk = 0;
 		sh = raid5_get_active_stripe(conf, stripe_addr+i, 0, 0, 1);
@@ -5916,7 +5943,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
 				skipped_disk = 1;
 				continue;
 			}
-			memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE);
+			memset(page_address(sh->dev[j].page), 0, RAID5_STRIPE_SIZE(conf));
 			set_bit(R5_Expanded, &sh->dev[j].flags);
 			set_bit(R5_UPTODATE, &sh->dev[j].flags);
 		}
@@ -5951,7 +5978,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
 		set_bit(STRIPE_EXPAND_SOURCE, &sh->state);
 		set_bit(STRIPE_HANDLE, &sh->state);
 		raid5_release_stripe(sh);
-		first_sector += STRIPE_SECTORS;
+		first_sector += RAID5_STRIPE_SECTORS(conf);
 	}
 	/* Now that the sources are clearly marked, we can release
 	 * the destination stripes
@@ -5998,7 +6025,7 @@ finish:
 		conf->reshape_safe = mddev->reshape_position;
 		spin_unlock_irq(&conf->device_lock);
 		wake_up(&conf->wait_for_overlap);
-		sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+		sysfs_notify_dirent_safe(mddev->sysfs_completed);
 	}
 ret:
 	return retn;
@@ -6057,11 +6084,12 @@ static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_n
 	if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
 	    !conf->fullsync &&
 	    !md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
-	    sync_blocks >= STRIPE_SECTORS) {
+	    sync_blocks >= RAID5_STRIPE_SECTORS(conf)) {
 		/* we can skip this block, and probably more */
-		sync_blocks /= STRIPE_SECTORS;
+		do_div(sync_blocks, RAID5_STRIPE_SECTORS(conf));
 		*skipped = 1;
-		return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */
+		/* keep things rounded to whole stripes */
+		return sync_blocks * RAID5_STRIPE_SECTORS(conf);
 	}
 
 	md_bitmap_cond_end_sync(mddev->bitmap, sector_nr, false);
@@ -6094,7 +6122,7 @@ static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_n
 
 	raid5_release_stripe(sh);
 
-	return STRIPE_SECTORS;
+	return RAID5_STRIPE_SECTORS(conf);
 }
 
 static int  retry_aligned_read(struct r5conf *conf, struct bio *raid_bio,
@@ -6117,14 +6145,14 @@ static int  retry_aligned_read(struct r5conf *conf, struct bio *raid_bio,
 	int handled = 0;
 
 	logical_sector = raid_bio->bi_iter.bi_sector &
-		~((sector_t)STRIPE_SECTORS-1);
+		~((sector_t)RAID5_STRIPE_SECTORS(conf)-1);
 	sector = raid5_compute_sector(conf, logical_sector,
 				      0, &dd_idx, NULL);
 	last_sector = bio_end_sector(raid_bio);
 
 	for (; logical_sector < last_sector;
-	     logical_sector += STRIPE_SECTORS,
-		     sector += STRIPE_SECTORS,
+	     logical_sector += RAID5_STRIPE_SECTORS(conf),
+		     sector += RAID5_STRIPE_SECTORS(conf),
 		     scnt++) {
 
 		if (scnt < offset)
@@ -6457,6 +6485,77 @@ raid5_rmw_level = __ATTR(rmw_level, S_IRUGO | S_IWUSR,
 			 raid5_show_rmw_level,
 			 raid5_store_rmw_level);
 
+static ssize_t
+raid5_show_stripe_size(struct mddev  *mddev, char *page)
+{
+	struct r5conf *conf;
+	int ret = 0;
+
+	spin_lock(&mddev->lock);
+	conf = mddev->private;
+	if (conf)
+		ret = sprintf(page, "%lu\n", RAID5_STRIPE_SIZE(conf));
+	spin_unlock(&mddev->lock);
+	return ret;
+}
+
+#if PAGE_SIZE != DEFAULT_STRIPE_SIZE
+static ssize_t
+raid5_store_stripe_size(struct mddev  *mddev, const char *page, size_t len)
+{
+	struct r5conf *conf;
+	unsigned long new;
+	int err;
+
+	if (len >= PAGE_SIZE)
+		return -EINVAL;
+	if (kstrtoul(page, 10, &new))
+		return -EINVAL;
+
+	/*
+	 * The value should not be bigger than PAGE_SIZE. It requires to
+	 * be multiple of DEFAULT_STRIPE_SIZE.
+	 */
+	if (new % DEFAULT_STRIPE_SIZE != 0 || new > PAGE_SIZE || new == 0)
+		return -EINVAL;
+
+	err = mddev_lock(mddev);
+	if (err)
+		return err;
+
+	conf = mddev->private;
+	if (!conf) {
+		err = -ENODEV;
+		goto out_unlock;
+	}
+
+	if (new == conf->stripe_size)
+		goto out_unlock;
+
+	pr_debug("md/raid: change stripe_size from %lu to %lu\n",
+			conf->stripe_size, new);
+
+	mddev_suspend(mddev);
+	conf->stripe_size = new;
+	conf->stripe_shift = ilog2(new) - 9;
+	conf->stripe_sectors = new >> 9;
+	mddev_resume(mddev);
+
+out_unlock:
+	mddev_unlock(mddev);
+	return err ?: len;
+}
+
+static struct md_sysfs_entry
+raid5_stripe_size = __ATTR(stripe_size, 0644,
+			 raid5_show_stripe_size,
+			 raid5_store_stripe_size);
+#else
+static struct md_sysfs_entry
+raid5_stripe_size = __ATTR(stripe_size, 0444,
+			 raid5_show_stripe_size,
+			 NULL);
+#endif
 
 static ssize_t
 raid5_show_preread_threshold(struct mddev *mddev, char *page)
@@ -6645,6 +6744,7 @@ static struct attribute *raid5_attrs[] =  {
 	&raid5_group_thread_cnt.attr,
 	&raid5_skip_copy.attr,
 	&raid5_rmw_level.attr,
+	&raid5_stripe_size.attr,
 	&r5c_journal_mode.attr,
 	&ppl_write_hint.attr,
 	NULL,
@@ -6744,7 +6844,7 @@ static int alloc_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu
 			       conf->previous_raid_disks),
 			   max(conf->chunk_sectors,
 			       conf->prev_chunk_sectors)
-			   / STRIPE_SECTORS)) {
+			   / RAID5_STRIPE_SECTORS(conf))) {
 		free_scratch_buffer(conf, percpu);
 		return -ENOMEM;
 	}
@@ -6896,6 +6996,12 @@ static struct r5conf *setup_conf(struct mddev *mddev)
 	conf = kzalloc(sizeof(struct r5conf), GFP_KERNEL);
 	if (conf == NULL)
 		goto abort;
+
+#if PAGE_SIZE != DEFAULT_STRIPE_SIZE
+	conf->stripe_size = DEFAULT_STRIPE_SIZE;
+	conf->stripe_shift = ilog2(DEFAULT_STRIPE_SIZE) - 9;
+	conf->stripe_sectors = DEFAULT_STRIPE_SIZE >> 9;
+#endif
 	INIT_LIST_HEAD(&conf->free_list);
 	INIT_LIST_HEAD(&conf->pending_list);
 	conf->pending_data = kcalloc(PENDING_IO_MAX,
@@ -7047,8 +7153,8 @@ static struct r5conf *setup_conf(struct mddev *mddev)
 	conf->min_nr_stripes = NR_STRIPES;
 	if (mddev->reshape_position != MaxSector) {
 		int stripes = max_t(int,
-			((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4,
-			((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4);
+			((mddev->chunk_sectors << 9) / RAID5_STRIPE_SIZE(conf)) * 4,
+			((mddev->new_chunk_sectors << 9) / RAID5_STRIPE_SIZE(conf)) * 4);
 		conf->min_nr_stripes = max(NR_STRIPES, stripes);
 		if (conf->min_nr_stripes != NR_STRIPES)
 			pr_info("md/raid:%s: force stripe size %d for reshape\n",
@@ -7779,14 +7885,14 @@ static int check_stripe_cache(struct mddev *mddev)
 	 * stripe_heads first.
 	 */
 	struct r5conf *conf = mddev->private;
-	if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4
+	if (((mddev->chunk_sectors << 9) / RAID5_STRIPE_SIZE(conf)) * 4
 	    > conf->min_nr_stripes ||
-	    ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4
+	    ((mddev->new_chunk_sectors << 9) / RAID5_STRIPE_SIZE(conf)) * 4
 	    > conf->min_nr_stripes) {
 		pr_warn("md/raid:%s: reshape: not enough stripes.  Needed %lu\n",
 			mdname(mddev),
 			((max(mddev->chunk_sectors, mddev->new_chunk_sectors) << 9)
-			 / STRIPE_SIZE)*4);
+			 / RAID5_STRIPE_SIZE(conf))*4);
 		return 0;
 	}
 	return 1;
@@ -7922,8 +8028,8 @@ static int raid5_start_reshape(struct mddev *mddev)
 					else
 						rdev->recovery_offset = 0;
 
-					if (sysfs_link_rdev(mddev, rdev))
-						/* Failure here is OK */;
+					/* Failure here is OK */
+					sysfs_link_rdev(mddev, rdev);
 				}
 			} else if (rdev->raid_disk >= conf->previous_raid_disks
 				   && !test_bit(Faulty, &rdev->flags)) {
@@ -8118,7 +8224,7 @@ static void *raid5_takeover_raid1(struct mddev *mddev)
 	while (chunksect && (mddev->array_sectors & (chunksect-1)))
 		chunksect >>= 1;
 
-	if ((chunksect<<9) < STRIPE_SIZE)
+	if ((chunksect<<9) < RAID5_STRIPE_SIZE((struct r5conf *)mddev->private))
 		/* array size does not allow a suitable chunk size */
 		return ERR_PTR(-EINVAL);
 
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index f90e0704bed9..7fb3b26a181a 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -472,32 +472,20 @@ struct disk_info {
  */
 
 #define NR_STRIPES		256
+#define DEFAULT_STRIPE_SIZE	4096
+
+#if PAGE_SIZE == DEFAULT_STRIPE_SIZE
 #define STRIPE_SIZE		PAGE_SIZE
 #define STRIPE_SHIFT		(PAGE_SHIFT - 9)
 #define STRIPE_SECTORS		(STRIPE_SIZE>>9)
+#endif
+
 #define	IO_THRESHOLD		1
 #define BYPASS_THRESHOLD	1
 #define NR_HASH			(PAGE_SIZE / sizeof(struct hlist_head))
 #define HASH_MASK		(NR_HASH - 1)
 #define MAX_STRIPE_BATCH	8
 
-/* bio's attached to a stripe+device for I/O are linked together in bi_sector
- * order without overlap.  There may be several bio's per stripe+device, and
- * a bio could span several devices.
- * When walking this list for a particular stripe+device, we must never proceed
- * beyond a bio that extends past this device, as the next bio might no longer
- * be valid.
- * This function is used to determine the 'next' bio in the list, given the
- * sector of the current stripe+device
- */
-static inline struct bio *r5_next_bio(struct bio *bio, sector_t sector)
-{
-	if (bio_end_sector(bio) < sector + STRIPE_SECTORS)
-		return bio->bi_next;
-	else
-		return NULL;
-}
-
 /* NOTE NR_STRIPE_HASH_LOCKS must remain below 64.
  * This is because we sometimes take all the spinlocks
  * and creating that much locking depth can cause
@@ -574,6 +562,11 @@ struct r5conf {
 	int			raid_disks;
 	int			max_nr_stripes;
 	int			min_nr_stripes;
+#if PAGE_SIZE != DEFAULT_STRIPE_SIZE
+	unsigned long	stripe_size;
+	unsigned int	stripe_shift;
+	unsigned long	stripe_sectors;
+#endif
 
 	/* reshape_progress is the leading edge of a 'reshape'
 	 * It has value MaxSector when no reshape is happening
@@ -690,6 +683,32 @@ struct r5conf {
 	struct r5pending_data	*next_pending_data;
 };
 
+#if PAGE_SIZE == DEFAULT_STRIPE_SIZE
+#define RAID5_STRIPE_SIZE(conf)	STRIPE_SIZE
+#define RAID5_STRIPE_SHIFT(conf)	STRIPE_SHIFT
+#define RAID5_STRIPE_SECTORS(conf)	STRIPE_SECTORS
+#else
+#define RAID5_STRIPE_SIZE(conf)	((conf)->stripe_size)
+#define RAID5_STRIPE_SHIFT(conf)	((conf)->stripe_shift)
+#define RAID5_STRIPE_SECTORS(conf)	((conf)->stripe_sectors)
+#endif
+
+/* bio's attached to a stripe+device for I/O are linked together in bi_sector
+ * order without overlap.  There may be several bio's per stripe+device, and
+ * a bio could span several devices.
+ * When walking this list for a particular stripe+device, we must never proceed
+ * beyond a bio that extends past this device, as the next bio might no longer
+ * be valid.
+ * This function is used to determine the 'next' bio in the list, given the
+ * sector of the current stripe+device
+ */
+static inline struct bio *r5_next_bio(struct r5conf *conf, struct bio *bio, sector_t sector)
+{
+	if (bio_end_sector(bio) < sector + RAID5_STRIPE_SECTORS(conf))
+		return bio->bi_next;
+	else
+		return NULL;
+}
 
 /*
  * Our supported algorithms