Update bcachefs sources to ca97ee3577 bcachefs: bch2_btree_iter_peek_and_restart_outlined()

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

25 files changed, 524 insertions, 305 deletions

diff --git a/.bcachefs_revision b/.bcachefs_revision
index 93724d8b..44599a02 100644
--- a/.bcachefs_revision
+++ b/.bcachefs_revision
@@ -1 +1 @@
-8e1519ccb62b76736d5b9ca97e58b41ed9a11274
+ca97ee357774427208e4c251bfaa5957ae7f8c2c
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 01b3d4ad..f78621d8 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -70,6 +70,7 @@ static inline void submit_bio(struct bio *bio)
 }
 
 int blkdev_issue_discard(struct block_device *, sector_t, sector_t, gfp_t);
+int blkdev_issue_zeroout(struct block_device *, sector_t, sector_t, gfp_t, unsigned);
 
 #define bdev_get_queue(bdev)		(&((bdev)->queue))
 
diff --git a/include/trace/events/bcachefs.h b/include/trace/events/bcachefs.h
index d1e2f979..ae184220 100644
--- a/include/trace/events/bcachefs.h
+++ b/include/trace/events/bcachefs.h
@@ -516,7 +516,6 @@ DEFINE_EVENT(bch_fs, gc_gens_end,
 
 DECLARE_EVENT_CLASS(bucket_alloc,
 	TP_PROTO(struct bch_dev *ca, const char *alloc_reserve,
-		 bool user,
 		 u64 bucket,
 		 u64 free,
 		 u64 avail,
@@ -525,14 +524,13 @@ DECLARE_EVENT_CLASS(bucket_alloc,
 		 struct bucket_alloc_state *s,
 		 bool nonblocking,
 		 const char *err),
-	TP_ARGS(ca, alloc_reserve, user, bucket, free, avail,
+	TP_ARGS(ca, alloc_reserve, bucket, free, avail,
 		copygc_wait_amount, copygc_waiting_for,
 		s, nonblocking, err),
 
 	TP_STRUCT__entry(
-		__field(dev_t,			dev			)
+		__field(u8,			dev			)
 		__array(char,	reserve,	16			)
-		__field(bool,			user	)
 		__field(u64,			bucket	)
 		__field(u64,			free			)
 		__field(u64,			avail			)
@@ -548,9 +546,8 @@ DECLARE_EVENT_CLASS(bucket_alloc,
 	),
 
 	TP_fast_assign(
-		__entry->dev		= ca->dev;
+		__entry->dev		= ca->dev_idx;
 		strscpy(__entry->reserve, alloc_reserve, sizeof(__entry->reserve));
-		__entry->user		= user;
 		__entry->bucket		= bucket;
 		__entry->free		= free;
 		__entry->avail		= avail;
@@ -565,10 +562,9 @@ DECLARE_EVENT_CLASS(bucket_alloc,
 		strscpy(__entry->err, err, sizeof(__entry->err));
 	),
 
-	TP_printk("%d,%d reserve %s user %u bucket %llu free %llu avail %llu copygc_wait %llu/%lli seen %llu open %llu need_journal_commit %llu nouse %llu nocow %llu nonblocking %u err %s",
-		  MAJOR(__entry->dev), MINOR(__entry->dev),
+	TP_printk("reserve %s bucket %u:%llu free %llu avail %llu copygc_wait %llu/%lli seen %llu open %llu need_journal_commit %llu nouse %llu nocow %llu nonblocking %u err %s",
 		  __entry->reserve,
-		  __entry->user,
+		  __entry->dev,
 		  __entry->bucket,
 		  __entry->free,
 		  __entry->avail,
@@ -585,7 +581,6 @@ DECLARE_EVENT_CLASS(bucket_alloc,
 
 DEFINE_EVENT(bucket_alloc, bucket_alloc,
 	TP_PROTO(struct bch_dev *ca, const char *alloc_reserve,
-		 bool user,
 		 u64 bucket,
 		 u64 free,
 		 u64 avail,
@@ -594,14 +589,13 @@ DEFINE_EVENT(bucket_alloc, bucket_alloc,
 		 struct bucket_alloc_state *s,
 		 bool nonblocking,
 		 const char *err),
-	TP_ARGS(ca, alloc_reserve, user, bucket, free, avail,
+	TP_ARGS(ca, alloc_reserve, bucket, free, avail,
 		copygc_wait_amount, copygc_waiting_for,
 		s, nonblocking, err)
 );
 
 DEFINE_EVENT(bucket_alloc, bucket_alloc_fail,
 	TP_PROTO(struct bch_dev *ca, const char *alloc_reserve,
-		 bool user,
 		 u64 bucket,
 		 u64 free,
 		 u64 avail,
@@ -610,7 +604,7 @@ DEFINE_EVENT(bucket_alloc, bucket_alloc_fail,
 		 struct bucket_alloc_state *s,
 		 bool nonblocking,
 		 const char *err),
-	TP_ARGS(ca, alloc_reserve, user, bucket, free, avail,
+	TP_ARGS(ca, alloc_reserve, bucket, free, avail,
 		copygc_wait_amount, copygc_waiting_for,
 		s, nonblocking, err)
 );
diff --git a/libbcachefs/alloc_background.c b/libbcachefs/alloc_background.c
index b39a4533..5f4bb82c 100644
--- a/libbcachefs/alloc_background.c
+++ b/libbcachefs/alloc_background.c
@@ -2175,21 +2175,24 @@ void bch2_dev_allocator_remove(struct bch_fs *c, struct bch_dev *ca)
 	}
 	mutex_unlock(&c->btree_reserve_cache_lock);
 
-	while (1) {
-		struct open_bucket *ob;
-
-		spin_lock(&c->freelist_lock);
-		if (!ca->open_buckets_partial_nr) {
+	spin_lock(&c->freelist_lock);
+	i = 0;
+	while (i < c->open_buckets_partial_nr) {
+		struct open_bucket *ob =
+			c->open_buckets + c->open_buckets_partial[i];
+
+		if (ob->dev == ca->dev_idx) {
+			swap(c->open_buckets_partial[i],
+			     c->open_buckets_partial[--c->open_buckets_partial_nr]);
+			ob->on_partial_list = false;
 			spin_unlock(&c->freelist_lock);
-			break;
+			bch2_open_bucket_put(c, ob);
+			spin_lock(&c->freelist_lock);
+		} else {
+			i++;
 		}
-		ob = c->open_buckets +
-			ca->open_buckets_partial[--ca->open_buckets_partial_nr];
-		ob->on_partial_list = false;
-		spin_unlock(&c->freelist_lock);
-
-		bch2_open_bucket_put(c, ob);
 	}
+	spin_unlock(&c->freelist_lock);
 
 	bch2_ec_stop_dev(c, ca);
 
diff --git a/libbcachefs/alloc_foreground.c b/libbcachefs/alloc_foreground.c
index affddf1f..023b62c5 100644
--- a/libbcachefs/alloc_foreground.c
+++ b/libbcachefs/alloc_foreground.c
@@ -154,26 +154,17 @@ static void open_bucket_free_unused(struct bch_fs *c,
 				    struct write_point *wp,
 				    struct open_bucket *ob)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
-	bool may_realloc = wp->data_type == BCH_DATA_user;
-
-	BUG_ON(ca->open_buckets_partial_nr >
-	       ARRAY_SIZE(ca->open_buckets_partial));
-
-	if (ca->open_buckets_partial_nr <
-	    ARRAY_SIZE(ca->open_buckets_partial) &&
-	    may_realloc) {
-		spin_lock(&c->freelist_lock);
-		ob->on_partial_list = true;
-		ca->open_buckets_partial[ca->open_buckets_partial_nr++] =
-			ob - c->open_buckets;
-		spin_unlock(&c->freelist_lock);
+	BUG_ON(c->open_buckets_partial_nr >=
+	       ARRAY_SIZE(c->open_buckets_partial));
 
-		closure_wake_up(&c->open_buckets_wait);
-		closure_wake_up(&c->freelist_wait);
-	} else {
-		bch2_open_bucket_put(c, ob);
-	}
+	spin_lock(&c->freelist_lock);
+	ob->on_partial_list = true;
+	c->open_buckets_partial[c->open_buckets_partial_nr++] =
+		ob - c->open_buckets;
+	spin_unlock(&c->freelist_lock);
+
+	closure_wake_up(&c->open_buckets_wait);
+	closure_wake_up(&c->freelist_wait);
 }
 
 /* _only_ for allocating the journal on a new device: */
@@ -259,7 +250,6 @@ static struct open_bucket *__try_alloc_bucket(struct bch_fs *c, struct bch_dev *
 
 	ob->valid	= true;
 	ob->sectors_free = ca->mi.bucket_size;
-	ob->alloc_reserve = reserve;
 	ob->dev		= ca->dev_idx;
 	ob->gen		= a->gen;
 	ob->bucket	= bucket;
@@ -386,32 +376,6 @@ err:
 	return ob;
 }
 
-static struct open_bucket *try_alloc_partial_bucket(struct bch_fs *c, struct bch_dev *ca,
-						    enum alloc_reserve reserve)
-{
-	struct open_bucket *ob;
-	int i;
-
-	spin_lock(&c->freelist_lock);
-
-	for (i = ca->open_buckets_partial_nr - 1; i >= 0; --i) {
-		ob = c->open_buckets + ca->open_buckets_partial[i];
-
-		if (reserve <= ob->alloc_reserve) {
-			array_remove_item(ca->open_buckets_partial,
-					  ca->open_buckets_partial_nr,
-					  i);
-			ob->on_partial_list = false;
-			ob->alloc_reserve = reserve;
-			spin_unlock(&c->freelist_lock);
-			return ob;
-		}
-	}
-
-	spin_unlock(&c->freelist_lock);
-	return NULL;
-}
-
 /*
  * This path is for before the freespace btree is initialized:
  *
@@ -535,7 +499,6 @@ again:
 static struct open_bucket *bch2_bucket_alloc_trans(struct btree_trans *trans,
 				      struct bch_dev *ca,
 				      enum alloc_reserve reserve,
-				      bool may_alloc_partial,
 				      struct closure *cl,
 				      struct bch_dev_usage *usage)
 {
@@ -574,12 +537,6 @@ again:
 
 	if (waiting)
 		closure_wake_up(&c->freelist_wait);
-
-	if (may_alloc_partial) {
-		ob = try_alloc_partial_bucket(c, ca, reserve);
-		if (ob)
-			return ob;
-	}
 alloc:
 	ob = likely(freespace)
 		? bch2_bucket_alloc_freelist(trans, ca, reserve, &s, cl)
@@ -599,7 +556,6 @@ err:
 	if (!IS_ERR(ob))
 		trace_and_count(c, bucket_alloc, ca,
 				bch2_alloc_reserves[reserve],
-				may_alloc_partial,
 				ob->bucket,
 				usage->d[BCH_DATA_free].buckets,
 				avail,
@@ -611,7 +567,6 @@ err:
 	else if (!bch2_err_matches(PTR_ERR(ob), BCH_ERR_transaction_restart))
 		trace_and_count(c, bucket_alloc_fail, ca,
 				bch2_alloc_reserves[reserve],
-				may_alloc_partial,
 				0,
 				usage->d[BCH_DATA_free].buckets,
 				avail,
@@ -626,7 +581,6 @@ err:
 
 struct open_bucket *bch2_bucket_alloc(struct bch_fs *c, struct bch_dev *ca,
 				      enum alloc_reserve reserve,
-				      bool may_alloc_partial,
 				      struct closure *cl)
 {
 	struct bch_dev_usage usage;
@@ -634,7 +588,7 @@ struct open_bucket *bch2_bucket_alloc(struct bch_fs *c, struct bch_dev *ca,
 
 	bch2_trans_do(c, NULL, NULL, 0,
 		      PTR_ERR_OR_ZERO(ob = bch2_bucket_alloc_trans(&trans, ca, reserve,
-							may_alloc_partial, cl, &usage)));
+							cl, &usage)));
 	return ob;
 }
 
@@ -691,12 +645,10 @@ void bch2_dev_stripe_increment(struct bch_dev *ca,
 	bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
 }
 
-#define BUCKET_MAY_ALLOC_PARTIAL	(1 << 0)
-#define BUCKET_ALLOC_USE_DURABILITY	(1 << 1)
-
-static void add_new_bucket(struct bch_fs *c,
+static int add_new_bucket(struct bch_fs *c,
 			   struct open_buckets *ptrs,
 			   struct bch_devs_mask *devs_may_alloc,
+			   unsigned nr_replicas,
 			   unsigned *nr_effective,
 			   bool *have_cache,
 			   unsigned flags,
@@ -705,12 +657,19 @@ static void add_new_bucket(struct bch_fs *c,
 	unsigned durability =
 		bch_dev_bkey_exists(c, ob->dev)->mi.durability;
 
+	BUG_ON(*nr_effective >= nr_replicas);
+
 	__clear_bit(ob->dev, devs_may_alloc->d);
-	*nr_effective	+= (flags & BUCKET_ALLOC_USE_DURABILITY)
-		? durability : 1;
+	*nr_effective	+= durability;
 	*have_cache	|= !durability;
 
 	ob_push(c, ptrs, ob);
+
+	if (*nr_effective >= nr_replicas)
+		return 1;
+	if (ob->ec)
+		return 1;
+	return 0;
 }
 
 int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
@@ -720,8 +679,8 @@ int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 		      unsigned nr_replicas,
 		      unsigned *nr_effective,
 		      bool *have_cache,
+		      enum bch_data_type data_type,
 		      enum alloc_reserve reserve,
-		      unsigned flags,
 		      struct closure *cl)
 {
 	struct bch_fs *c = trans->c;
@@ -754,8 +713,7 @@ int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 			continue;
 		}
 
-		ob = bch2_bucket_alloc_trans(trans, ca, reserve,
-				flags & BUCKET_MAY_ALLOC_PARTIAL, cl, &usage);
+		ob = bch2_bucket_alloc_trans(trans, ca, reserve, cl, &usage);
 		if (!IS_ERR(ob))
 			bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
 		percpu_ref_put(&ca->ref);
@@ -767,10 +725,11 @@ int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 			continue;
 		}
 
-		add_new_bucket(c, ptrs, devs_may_alloc,
-			       nr_effective, have_cache, flags, ob);
+		ob->data_type = data_type;
 
-		if (*nr_effective >= nr_replicas) {
+		if (add_new_bucket(c, ptrs, devs_may_alloc,
+				   nr_replicas, nr_effective,
+				   have_cache, 0, ob)) {
 			ret = 0;
 			break;
 		}
@@ -792,7 +751,6 @@ static int bucket_alloc_from_stripe(struct btree_trans *trans,
 			 struct write_point *wp,
 			 struct bch_devs_mask *devs_may_alloc,
 			 u16 target,
-			 unsigned erasure_code,
 			 unsigned nr_replicas,
 			 unsigned *nr_effective,
 			 bool *have_cache,
@@ -805,9 +763,7 @@ static int bucket_alloc_from_stripe(struct btree_trans *trans,
 	struct open_bucket *ob;
 	struct bch_dev *ca;
 	unsigned i, ec_idx;
-
-	if (!erasure_code)
-		return 0;
+	int ret = 0;
 
 	if (nr_replicas < 2)
 		return 0;
@@ -842,54 +798,122 @@ got_bucket:
 	ob->ec_idx	= ec_idx;
 	ob->ec		= h->s;
 
-	add_new_bucket(c, ptrs, devs_may_alloc,
-		       nr_effective, have_cache, flags, ob);
+	ret = add_new_bucket(c, ptrs, devs_may_alloc,
+			     nr_replicas, nr_effective,
+			     have_cache, flags, ob);
 	atomic_inc(&h->s->pin);
 out_put_head:
 	bch2_ec_stripe_head_put(c, h);
-	return 0;
+	return ret;
 }
 
 /* Sector allocator */
 
-static void get_buckets_from_writepoint(struct bch_fs *c,
-					struct open_buckets *ptrs,
-					struct write_point *wp,
-					struct bch_devs_mask *devs_may_alloc,
-					unsigned nr_replicas,
-					unsigned *nr_effective,
-					bool *have_cache,
-					unsigned flags,
-					bool need_ec)
+static bool want_bucket(struct bch_fs *c,
+			struct write_point *wp,
+			struct bch_devs_mask *devs_may_alloc,
+			bool *have_cache, bool ec,
+			struct open_bucket *ob)
+{
+	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+
+	if (!test_bit(ob->dev, devs_may_alloc->d))
+		return false;
+
+	if (ob->data_type != wp->data_type)
+		return false;
+
+	if (!ca->mi.durability &&
+	    (wp->data_type != BCH_DATA_user || !*have_cache))
+		return false;
+
+	if (ec != (ob->ec != NULL))
+		return false;
+
+	return true;
+}
+
+static int bucket_alloc_set_writepoint(struct bch_fs *c,
+				       struct open_buckets *ptrs,
+				       struct write_point *wp,
+				       struct bch_devs_mask *devs_may_alloc,
+				       unsigned nr_replicas,
+				       unsigned *nr_effective,
+				       bool *have_cache,
+				       bool ec, unsigned flags)
 {
 	struct open_buckets ptrs_skip = { .nr = 0 };
 	struct open_bucket *ob;
 	unsigned i;
+	int ret = 0;
 
 	open_bucket_for_each(c, &wp->ptrs, ob, i) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
-
-		if (*nr_effective < nr_replicas &&
-		    test_bit(ob->dev, devs_may_alloc->d) &&
-		    (ca->mi.durability ||
-		     (wp->data_type == BCH_DATA_user && !*have_cache)) &&
-		    (ob->ec || !need_ec)) {
-			add_new_bucket(c, ptrs, devs_may_alloc,
-				       nr_effective, have_cache,
-				       flags, ob);
-		} else {
+		if (!ret && want_bucket(c, wp, devs_may_alloc,
+					have_cache, ec, ob))
+			ret = add_new_bucket(c, ptrs, devs_may_alloc,
+				       nr_replicas, nr_effective,
+				       have_cache, flags, ob);
+		else
 			ob_push(c, &ptrs_skip, ob);
-		}
 	}
 	wp->ptrs = ptrs_skip;
+
+	return ret;
 }
 
-static int open_bucket_add_buckets(struct btree_trans *trans,
+static int bucket_alloc_set_partial(struct bch_fs *c,
+				    struct open_buckets *ptrs,
+				    struct write_point *wp,
+				    struct bch_devs_mask *devs_may_alloc,
+				    unsigned nr_replicas,
+				    unsigned *nr_effective,
+				    bool *have_cache, bool ec,
+				    enum alloc_reserve reserve,
+				    unsigned flags)
+{
+	int i, ret = 0;
+
+	if (!c->open_buckets_partial_nr)
+		return 0;
+
+	spin_lock(&c->freelist_lock);
+
+	for (i = c->open_buckets_partial_nr - 1; i >= 0; --i) {
+		struct open_bucket *ob = c->open_buckets + c->open_buckets_partial[i];
+
+		if (want_bucket(c, wp, devs_may_alloc, have_cache, ec, ob)) {
+			struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+			struct bch_dev_usage usage;
+			u64 avail;
+
+			bch2_dev_usage_read_fast(ca, &usage);
+			avail = dev_buckets_free(ca, usage, reserve);
+			if (!avail)
+				continue;
+
+			array_remove_item(c->open_buckets_partial,
+					  c->open_buckets_partial_nr,
+					  i);
+			ob->on_partial_list = false;
+
+			ret = add_new_bucket(c, ptrs, devs_may_alloc,
+					     nr_replicas, nr_effective,
+					     have_cache, flags, ob);
+			if (ret)
+				break;
+		}
+	}
+
+	spin_unlock(&c->freelist_lock);
+	return ret;
+}
+
+static int __open_bucket_add_buckets(struct btree_trans *trans,
 			struct open_buckets *ptrs,
 			struct write_point *wp,
 			struct bch_devs_list *devs_have,
 			u16 target,
-			unsigned erasure_code,
+			bool erasure_code,
 			unsigned nr_replicas,
 			unsigned *nr_effective,
 			bool *have_cache,
@@ -901,8 +925,8 @@ static int open_bucket_add_buckets(struct btree_trans *trans,
 	struct bch_devs_mask devs;
 	struct open_bucket *ob;
 	struct closure *cl = NULL;
-	int ret;
 	unsigned i;
+	int ret;
 
 	rcu_read_lock();
 	devs = target_rw_devs(c, wp->data_type, target);
@@ -915,52 +939,82 @@ static int open_bucket_add_buckets(struct btree_trans *trans,
 	open_bucket_for_each(c, ptrs, ob, i)
 		__clear_bit(ob->dev, devs.d);
 
+	if (erasure_code && ec_open_bucket(c, ptrs))
+		return 0;
+
+	ret = bucket_alloc_set_writepoint(c, ptrs, wp, &devs,
+				 nr_replicas, nr_effective,
+				 have_cache, erasure_code, flags);
+	if (ret)
+		return ret;
+
+	ret = bucket_alloc_set_partial(c, ptrs, wp, &devs,
+				 nr_replicas, nr_effective,
+				 have_cache, erasure_code, reserve, flags);
+	if (ret)
+		return ret;
+
 	if (erasure_code) {
-		if (!ec_open_bucket(c, ptrs)) {
-			get_buckets_from_writepoint(c, ptrs, wp, &devs,
-						    nr_replicas, nr_effective,
-						    have_cache, flags, true);
-			if (*nr_effective >= nr_replicas)
-				return 0;
+		ret = bucket_alloc_from_stripe(trans, ptrs, wp, &devs,
+					 target,
+					 nr_replicas, nr_effective,
+					 have_cache, flags, _cl);
+	} else {
+retry_blocking:
+		/*
+		 * Try nonblocking first, so that if one device is full we'll try from
+		 * other devices:
+		 */
+		ret = bch2_bucket_alloc_set_trans(trans, ptrs, &wp->stripe, &devs,
+					nr_replicas, nr_effective, have_cache,
+					wp->data_type, reserve, cl);
+		if (ret &&
+		    !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
+		    !bch2_err_matches(ret, BCH_ERR_insufficient_devices) &&
+		    !cl && _cl) {
+			cl = _cl;
+			goto retry_blocking;
 		}
 
-		if (!ec_open_bucket(c, ptrs)) {
-			ret = bucket_alloc_from_stripe(trans, ptrs, wp, &devs,
-						 target, erasure_code,
-						 nr_replicas, nr_effective,
-						 have_cache, flags, _cl);
-			if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
-			    bch2_err_matches(ret, BCH_ERR_freelist_empty) ||
-			    bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
-				return ret;
-			if (*nr_effective >= nr_replicas)
-				return 0;
-		}
 	}
 
-	get_buckets_from_writepoint(c, ptrs, wp, &devs,
-				    nr_replicas, nr_effective,
-				    have_cache, flags, false);
-	if (*nr_effective >= nr_replicas)
-		return 0;
+	return ret;
+}
 
-retry_blocking:
-	/*
-	 * Try nonblocking first, so that if one device is full we'll try from
-	 * other devices:
-	 */
-	ret = bch2_bucket_alloc_set_trans(trans, ptrs, &wp->stripe, &devs,
+static int open_bucket_add_buckets(struct btree_trans *trans,
+			struct open_buckets *ptrs,
+			struct write_point *wp,
+			struct bch_devs_list *devs_have,
+			u16 target,
+			unsigned erasure_code,
+			unsigned nr_replicas,
+			unsigned *nr_effective,
+			bool *have_cache,
+			enum alloc_reserve reserve,
+			unsigned flags,
+			struct closure *cl)
+{
+	int ret;
+
+	if (erasure_code) {
+		ret = __open_bucket_add_buckets(trans, ptrs, wp,
+				devs_have, target, erasure_code,
 				nr_replicas, nr_effective, have_cache,
 				reserve, flags, cl);
-	if (ret &&
-	    !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
-	    !bch2_err_matches(ret, BCH_ERR_insufficient_devices) &&
-	    !cl && _cl) {
-		cl = _cl;
-		goto retry_blocking;
+		if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
+		    bch2_err_matches(ret, BCH_ERR_operation_blocked) ||
+		    bch2_err_matches(ret, BCH_ERR_freelist_empty) ||
+		    bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
+			return ret;
+		if (*nr_effective >= nr_replicas)
+			return 0;
 	}
 
-	return ret;
+	ret = __open_bucket_add_buckets(trans, ptrs, wp,
+			devs_have, target, false,
+			nr_replicas, nr_effective, have_cache,
+			reserve, flags, cl);
+	return ret < 0 ? ret : 0;
 }
 
 void bch2_open_buckets_stop_dev(struct bch_fs *c, struct bch_dev *ca,
@@ -1159,14 +1213,10 @@ int bch2_alloc_sectors_start_trans(struct btree_trans *trans,
 	struct open_bucket *ob;
 	struct open_buckets ptrs;
 	unsigned nr_effective, write_points_nr;
-	unsigned ob_flags = 0;
 	bool have_cache;
 	int ret;
 	int i;
 
-	if (!(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS))
-		ob_flags |= BUCKET_ALLOC_USE_DURABILITY;
-
 	BUG_ON(!nr_replicas || !nr_replicas_required);
 retry:
 	ptrs.nr		= 0;
@@ -1176,9 +1226,6 @@ retry:
 
 	*wp_ret = wp = writepoint_find(trans, write_point.v);
 
-	if (wp->data_type == BCH_DATA_user)
-		ob_flags |= BUCKET_MAY_ALLOC_PARTIAL;
-
 	/* metadata may not allocate on cache devices: */
 	if (wp->data_type != BCH_DATA_user)
 		have_cache = true;
@@ -1188,13 +1235,13 @@ retry:
 					      target, erasure_code,
 					      nr_replicas, &nr_effective,
 					      &have_cache, reserve,
-					      ob_flags, cl);
+					      flags, cl);
 	} else {
 		ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
 					      target, erasure_code,
 					      nr_replicas, &nr_effective,
 					      &have_cache, reserve,
-					      ob_flags, NULL);
+					      flags, NULL);
 		if (!ret ||
 		    bch2_err_matches(ret, BCH_ERR_transaction_restart))
 			goto alloc_done;
@@ -1203,7 +1250,7 @@ retry:
 					      0, erasure_code,
 					      nr_replicas, &nr_effective,
 					      &have_cache, reserve,
-					      ob_flags, cl);
+					      flags, cl);
 	}
 alloc_done:
 	BUG_ON(!ret && nr_effective < nr_replicas);
@@ -1350,6 +1397,24 @@ void bch2_open_buckets_to_text(struct printbuf *out, struct bch_fs *c)
 	}
 }
 
+void bch2_open_buckets_partial_to_text(struct printbuf *out, struct bch_fs *c)
+{
+	unsigned i;
+
+	spin_lock(&c->freelist_lock);
+	for (i = 0; i < c->open_buckets_partial_nr; i++) {
+		struct open_bucket *ob = c->open_buckets + c->open_buckets_partial[i];
+
+		prt_printf(out, "%zu ref %u type %s ec %u %u:%llu:%u\n",
+			   ob - c->open_buckets,
+			   atomic_read(&ob->pin),
+			   bch2_data_types[ob->data_type],
+			   ob->ec != NULL,
+			   ob->dev, ob->bucket, ob->gen);
+	}
+	spin_unlock(&c->freelist_lock);
+}
+
 static const char * const bch2_write_point_states[] = {
 #define x(n)	#n,
 	WRITE_POINT_STATES()
diff --git a/libbcachefs/alloc_foreground.h b/libbcachefs/alloc_foreground.h
index ba7a87af..e9b3b142 100644
--- a/libbcachefs/alloc_foreground.h
+++ b/libbcachefs/alloc_foreground.h
@@ -31,8 +31,7 @@ void bch2_dev_stripe_increment(struct bch_dev *, struct dev_stripe_state *);
 long bch2_bucket_alloc_new_fs(struct bch_dev *);
 
 struct open_bucket *bch2_bucket_alloc(struct bch_fs *, struct bch_dev *,
-				      enum alloc_reserve, bool,
-				      struct closure *);
+				      enum alloc_reserve, struct closure *);
 
 static inline void ob_push(struct bch_fs *c, struct open_buckets *obs,
 			   struct open_bucket *ob)
@@ -152,8 +151,9 @@ static inline bool bch2_bucket_is_open_safe(struct bch_fs *c, unsigned dev, u64
 
 int bch2_bucket_alloc_set_trans(struct btree_trans *, struct open_buckets *,
 		      struct dev_stripe_state *, struct bch_devs_mask *,
-		      unsigned, unsigned *, bool *, enum alloc_reserve,
-		      unsigned, struct closure *);
+		      unsigned, unsigned *, bool *,
+		      enum bch_data_type, enum alloc_reserve,
+		      struct closure *);
 
 int bch2_alloc_sectors_start_trans(struct btree_trans *,
 				   unsigned, unsigned,
@@ -221,6 +221,7 @@ static inline struct write_point_specifier writepoint_ptr(struct write_point *wp
 void bch2_fs_allocator_foreground_init(struct bch_fs *);
 
 void bch2_open_buckets_to_text(struct printbuf *, struct bch_fs *);
+void bch2_open_buckets_partial_to_text(struct printbuf *, struct bch_fs *);
 
 void bch2_write_points_to_text(struct printbuf *, struct bch_fs *);
 
diff --git a/libbcachefs/alloc_types.h b/libbcachefs/alloc_types.h
index 2e6f4806..0739bf92 100644
--- a/libbcachefs/alloc_types.h
+++ b/libbcachefs/alloc_types.h
@@ -51,10 +51,9 @@ struct open_bucket {
 	 * the block in the stripe this open_bucket corresponds to:
 	 */
 	u8			ec_idx;
-	enum bch_data_type	data_type:8;
+	enum bch_data_type	data_type:6;
 	unsigned		valid:1;
 	unsigned		on_partial_list:1;
-	unsigned		alloc_reserve:3;
 
 	u8			dev;
 	u8			gen;
diff --git a/libbcachefs/backpointers.c b/libbcachefs/backpointers.c
index e001f419..a40c2612 100644
--- a/libbcachefs/backpointers.c
+++ b/libbcachefs/backpointers.c
@@ -932,11 +932,14 @@ static int check_one_backpointer(struct btree_trans *trans,
 				 struct bpos bucket,
 				 u64 *bp_offset,
 				 struct bbpos start,
-				 struct bbpos end)
+				 struct bbpos end,
+				 struct bpos *last_flushed_pos)
 {
+	struct bch_fs *c = trans->c;
 	struct btree_iter iter;
 	struct bch_backpointer bp;
 	struct bbpos pos;
+	struct bpos bp_pos;
 	struct bkey_s_c k;
 	struct printbuf buf = PRINTBUF;
 	int ret;
@@ -957,17 +960,31 @@ static int check_one_backpointer(struct btree_trans *trans,
 	if (ret)
 		return ret;
 
-	if (fsck_err_on(!k.k, trans->c,
+	bp_pos = bucket_pos_to_bp(c, bucket,
+			max(*bp_offset, BACKPOINTER_OFFSET_MAX) - BACKPOINTER_OFFSET_MAX);
+
+	if (!k.k && !bpos_eq(*last_flushed_pos, bp_pos)) {
+		*last_flushed_pos = bp_pos;
+		pr_info("flushing at %llu:%llu",
+			last_flushed_pos->inode,
+			last_flushed_pos->offset);
+
+		ret = bch2_btree_write_buffer_flush_sync(trans) ?:
+			-BCH_ERR_transaction_restart_write_buffer_flush;
+		goto out;
+	}
+
+	if (fsck_err_on(!k.k, c,
 			"%s backpointer points to missing extent\n%s",
 			*bp_offset < BACKPOINTER_OFFSET_MAX ? "alloc" : "btree",
 			(bch2_backpointer_to_text(&buf, &bp), buf.buf))) {
 		ret = bch2_backpointer_del_by_offset(trans, bucket, *bp_offset, bp);
 		if (ret == -ENOENT)
-			bch_err(trans->c, "backpointer at %llu not found", *bp_offset);
+			bch_err(c, "backpointer at %llu not found", *bp_offset);
 	}
-
-	bch2_trans_iter_exit(trans, &iter);
+out:
 fsck_err:
+	bch2_trans_iter_exit(trans, &iter);
 	printbuf_exit(&buf);
 	return ret;
 }
@@ -978,6 +995,7 @@ static int bch2_check_backpointers_to_extents_pass(struct btree_trans *trans,
 {
 	struct btree_iter iter;
 	struct bkey_s_c k;
+	struct bpos last_flushed_pos = SPOS_MAX;
 	int ret = 0;
 
 	for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
@@ -987,7 +1005,8 @@ static int bch2_check_backpointers_to_extents_pass(struct btree_trans *trans,
 		while (!(ret = commit_do(trans, NULL, NULL,
 					 BTREE_INSERT_LAZY_RW|
 					 BTREE_INSERT_NOFAIL,
-				check_one_backpointer(trans, iter.pos, &bp_offset, start, end))) &&
+				check_one_backpointer(trans, iter.pos, &bp_offset,
+						      start, end, &last_flushed_pos))) &&
 		       bp_offset < U64_MAX)
 			bp_offset++;
 
diff --git a/libbcachefs/bcachefs.h b/libbcachefs/bcachefs.h
index 7f9c1087..3f88e7ea 100644
--- a/libbcachefs/bcachefs.h
+++ b/libbcachefs/bcachefs.h
@@ -516,9 +516,6 @@ struct bch_dev {
 	unsigned		nr_open_buckets;
 	unsigned		nr_btree_reserve;
 
-	open_bucket_idx_t	open_buckets_partial[OPEN_BUCKETS_COUNT];
-	open_bucket_idx_t	open_buckets_partial_nr;
-
 	size_t			inc_gen_needs_gc;
 	size_t			inc_gen_really_needs_gc;
 	size_t			buckets_waiting_on_journal;
@@ -859,6 +856,9 @@ struct bch_fs {
 	struct open_bucket	open_buckets[OPEN_BUCKETS_COUNT];
 	open_bucket_idx_t	open_buckets_hash[OPEN_BUCKETS_COUNT];
 
+	open_bucket_idx_t	open_buckets_partial[OPEN_BUCKETS_COUNT];
+	open_bucket_idx_t	open_buckets_partial_nr;
+
 	struct write_point	btree_write_point;
 	struct write_point	rebalance_write_point;
 
diff --git a/libbcachefs/btree_iter.c b/libbcachefs/btree_iter.c
index d5a9cfb0..c8b0cf5e 100644
--- a/libbcachefs/btree_iter.c
+++ b/libbcachefs/btree_iter.c
@@ -2568,6 +2568,18 @@ struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *iter)
 	return bch2_btree_iter_peek_slot(iter);
 }
 
+struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *iter)
+{
+	struct bkey_s_c k;
+
+	while (btree_trans_too_many_iters(iter->trans) ||
+	       (k = bch2_btree_iter_peek_type(iter, iter->flags),
+		bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
+		bch2_trans_begin(iter->trans);
+
+	return k;
+}
+
 /* new transactional stuff: */
 
 #ifdef CONFIG_BCACHEFS_DEBUG
diff --git a/libbcachefs/btree_iter.h b/libbcachefs/btree_iter.h
index 1225c4dd..448be089 100644
--- a/libbcachefs/btree_iter.h
+++ b/libbcachefs/btree_iter.h
@@ -596,6 +596,8 @@ static inline int btree_trans_too_many_iters(struct btree_trans *trans)
 	return 0;
 }
 
+struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *);
+
 static inline struct bkey_s_c
 __bch2_btree_iter_peek_and_restart(struct btree_trans *trans,
 				   struct btree_iter *iter, unsigned flags)
diff --git a/libbcachefs/btree_write_buffer.c b/libbcachefs/btree_write_buffer.c
index 6285532e..026c249a 100644
--- a/libbcachefs/btree_write_buffer.c
+++ b/libbcachefs/btree_write_buffer.c
@@ -64,6 +64,15 @@ static int bch2_btree_write_buffer_flush_one(struct btree_trans *trans,
 
 	bch2_btree_insert_key_leaf(trans, path, &wb->k, wb->journal_seq);
 	(*fast)++;
+
+	if (path->ref > 1) {
+		/*
+		 * We can't clone a path that has write locks: if the path is
+		 * shared, unlock before set_pos(), traverse():
+		 */
+		bch2_btree_node_unlock_write(trans, path, path->l[0].b);
+		*write_locked = false;
+	}
 	return 0;
 trans_commit:
 	return  bch2_trans_update(trans, iter, &wb->k, 0) ?:
diff --git a/libbcachefs/data_update.c b/libbcachefs/data_update.c
index de0575f6..e1467e11 100644
--- a/libbcachefs/data_update.c
+++ b/libbcachefs/data_update.c
@@ -98,8 +98,10 @@ static void bch2_bkey_mark_dev_cached(struct bkey_s k, unsigned dev)
 	struct bch_extent_ptr *ptr;
 
 	bkey_for_each_ptr(ptrs, ptr)
-		if (ptr->dev == dev)
-			ptr->cached = true;
+		if (ptr->dev == dev) {
+			bch2_extent_ptr_set_cached(k, ptr);
+			return;
+		}
 }
 
 static int __bch2_data_update_index_update(struct btree_trans *trans,
@@ -295,15 +297,7 @@ out:
 
 int bch2_data_update_index_update(struct bch_write_op *op)
 {
-	struct bch_fs *c = op->c;
-	struct btree_trans trans;
-	int ret;
-
-	bch2_trans_init(&trans, c, BTREE_ITER_MAX, 1024);
-	ret = __bch2_data_update_index_update(&trans, op);
-	bch2_trans_exit(&trans);
-
-	return ret;
+	return bch2_trans_run(op->c, __bch2_data_update_index_update(&trans, op));
 }
 
 void bch2_data_update_read_done(struct data_update *m,
@@ -326,8 +320,9 @@ void bch2_data_update_exit(struct data_update *update)
 	const struct bch_extent_ptr *ptr;
 
 	bkey_for_each_ptr(ptrs, ptr) {
-		bch2_bucket_nocow_unlock(&c->nocow_locks,
-					 PTR_BUCKET_POS(c, ptr), 0);
+		if (c->opts.nocow_enabled)
+			bch2_bucket_nocow_unlock(&c->nocow_locks,
+						 PTR_BUCKET_POS(c, ptr), 0);
 		percpu_ref_put(&bch_dev_bkey_exists(c, ptr->dev)->ref);
 	}
 
@@ -487,23 +482,26 @@ int bch2_data_update_init(struct btree_trans *trans,
 		if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
 			m->op.incompressible = true;
 
-		if (ctxt) {
-			move_ctxt_wait_event(ctxt, trans,
-					(locked = bch2_bucket_nocow_trylock(&c->nocow_locks,
-								  PTR_BUCKET_POS(c, &p.ptr), 0)) ||
-					!atomic_read(&ctxt->read_sectors));
-
-			if (!locked)
-				bch2_bucket_nocow_lock(&c->nocow_locks,
-						       PTR_BUCKET_POS(c, &p.ptr), 0);
-		} else {
-			if (!bch2_bucket_nocow_trylock(&c->nocow_locks,
-						       PTR_BUCKET_POS(c, &p.ptr), 0)) {
-				ret = -BCH_ERR_nocow_lock_blocked;
-				goto err;
+		if (c->opts.nocow_enabled) {
+			if (ctxt) {
+				move_ctxt_wait_event(ctxt, trans,
+						(locked = bch2_bucket_nocow_trylock(&c->nocow_locks,
+									  PTR_BUCKET_POS(c, &p.ptr), 0)) ||
+						!atomic_read(&ctxt->read_sectors));
+
+				if (!locked)
+					bch2_bucket_nocow_lock(&c->nocow_locks,
+							       PTR_BUCKET_POS(c, &p.ptr), 0);
+			} else {
+				if (!bch2_bucket_nocow_trylock(&c->nocow_locks,
+							       PTR_BUCKET_POS(c, &p.ptr), 0)) {
+					ret = -BCH_ERR_nocow_lock_blocked;
+					goto err;
+				}
 			}
+			ptrs_locked |= (1U << i);
 		}
-		ptrs_locked |= (1U << i);
+
 		i++;
 	}
 
diff --git a/libbcachefs/ec.c b/libbcachefs/ec.c
index 84d2a0c4..7bd68880 100644
--- a/libbcachefs/ec.c
+++ b/libbcachefs/ec.c
@@ -138,20 +138,28 @@ void bch2_stripe_to_text(struct printbuf *out, struct bch_fs *c,
 			 struct bkey_s_c k)
 {
 	const struct bch_stripe *s = bkey_s_c_to_stripe(k).v;
-	unsigned i;
+	unsigned i, nr_data = s->nr_blocks - s->nr_redundant;
 
 	prt_printf(out, "algo %u sectors %u blocks %u:%u csum %u gran %u",
 	       s->algorithm,
 	       le16_to_cpu(s->sectors),
-	       s->nr_blocks - s->nr_redundant,
+	       nr_data,
 	       s->nr_redundant,
 	       s->csum_type,
 	       1U << s->csum_granularity_bits);
 
-	for (i = 0; i < s->nr_blocks; i++)
-		prt_printf(out, " %u:%llu:%u", s->ptrs[i].dev,
-		       (u64) s->ptrs[i].offset,
-		       stripe_blockcount_get(s, i));
+	for (i = 0; i < s->nr_blocks; i++) {
+		const struct bch_extent_ptr *ptr = s->ptrs + i;
+		struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+		u32 offset;
+		u64 b = sector_to_bucket_and_offset(ca, ptr->offset, &offset);
+
+		prt_printf(out, " %u:%llu:%u", ptr->dev, b, offset);
+		if (i < nr_data)
+			prt_printf(out, "#%u", stripe_blockcount_get(s, i));
+		if (ptr_stale(ca, ptr))
+			prt_printf(out, " stale");
+	}
 }
 
 /* returns blocknr in stripe that we matched: */
@@ -442,15 +450,14 @@ static void ec_block_io(struct bch_fs *c, struct ec_stripe_buf *buf,
 	percpu_ref_put(&ca->io_ref);
 }
 
-static int get_stripe_key(struct bch_fs *c, u64 idx, struct ec_stripe_buf *stripe)
+static int get_stripe_key_trans(struct btree_trans *trans, u64 idx,
+				struct ec_stripe_buf *stripe)
 {
-	struct btree_trans trans;
 	struct btree_iter iter;
 	struct bkey_s_c k;
 	int ret;
 
-	bch2_trans_init(&trans, c, 0, 0);
-	bch2_trans_iter_init(&trans, &iter, BTREE_ID_stripes,
+	bch2_trans_iter_init(trans, &iter, BTREE_ID_stripes,
 			     POS(0, idx), BTREE_ITER_SLOTS);
 	k = bch2_btree_iter_peek_slot(&iter);
 	ret = bkey_err(k);
@@ -462,11 +469,15 @@ static int get_stripe_key(struct bch_fs *c, u64 idx, struct ec_stripe_buf *strip
 	}
 	bkey_reassemble(&stripe->key.k_i, k);
 err:
-	bch2_trans_iter_exit(&trans, &iter);
-	bch2_trans_exit(&trans);
+	bch2_trans_iter_exit(trans, &iter);
 	return ret;
 }
 
+static int get_stripe_key(struct bch_fs *c, u64 idx, struct ec_stripe_buf *stripe)
+{
+	return bch2_trans_run(c, get_stripe_key_trans(&trans, idx, stripe));
+}
+
 /* recovery read path: */
 int bch2_ec_read_extent(struct bch_fs *c, struct bch_read_bio *rbio)
 {
@@ -865,25 +876,6 @@ err:
 	return ret;
 }
 
-static void extent_stripe_ptr_add(struct bkey_s_extent e,
-				  struct ec_stripe_buf *s,
-				  struct bch_extent_ptr *ptr,
-				  unsigned block)
-{
-	struct bch_extent_stripe_ptr *dst = (void *) ptr;
-	union bch_extent_entry *end = extent_entry_last(e);
-
-	memmove_u64s_up(dst + 1, dst, (u64 *) end - (u64 *) dst);
-	e.k->u64s += sizeof(*dst) / sizeof(u64);
-
-	*dst = (struct bch_extent_stripe_ptr) {
-		.type = 1 << BCH_EXTENT_ENTRY_stripe_ptr,
-		.block		= block,
-		.redundancy	= s->key.v.nr_redundant,
-		.idx		= s->key.k.p.offset,
-	};
-}
-
 static int ec_stripe_update_extent(struct btree_trans *trans,
 				   struct bpos bucket, u8 gen,
 				   struct ec_stripe_buf *s,
@@ -895,6 +887,7 @@ static int ec_stripe_update_extent(struct btree_trans *trans,
 	struct bkey_s_c k;
 	const struct bch_extent_ptr *ptr_c;
 	struct bch_extent_ptr *ptr, *ec_ptr = NULL;
+	struct bch_extent_stripe_ptr stripe_ptr;
 	struct bkey_i *n;
 	int ret, dev, block;
 
@@ -933,16 +926,27 @@ static int ec_stripe_update_extent(struct btree_trans *trans,
 
 	dev = s->key.v.ptrs[block].dev;
 
-	n = bch2_bkey_make_mut(trans, k);
+	n = bch2_trans_kmalloc(trans, bkey_bytes(k.k) + sizeof(stripe_ptr));
 	ret = PTR_ERR_OR_ZERO(n);
 	if (ret)
 		goto out;
 
+	bkey_reassemble(n, k);
+
 	bch2_bkey_drop_ptrs(bkey_i_to_s(n), ptr, ptr->dev != dev);
 	ec_ptr = (void *) bch2_bkey_has_device(bkey_i_to_s_c(n), dev);
 	BUG_ON(!ec_ptr);
 
-	extent_stripe_ptr_add(bkey_i_to_s_extent(n), s, ec_ptr, block);
+	stripe_ptr = (struct bch_extent_stripe_ptr) {
+		.type = 1 << BCH_EXTENT_ENTRY_stripe_ptr,
+		.block		= block,
+		.redundancy	= s->key.v.nr_redundant,
+		.idx		= s->key.k.p.offset,
+	};
+
+	__extent_entry_insert(n,
+			(union bch_extent_entry *) ec_ptr,
+			(union bch_extent_entry *) &stripe_ptr);
 
 	ret = bch2_trans_update(trans, &iter, n, 0);
 out:
@@ -999,6 +1003,35 @@ err:
 	return ret;
 }
 
+static void zero_out_rest_of_ec_bucket(struct bch_fs *c,
+				       struct ec_stripe_new *s,
+				       unsigned block,
+				       struct open_bucket *ob)
+{
+	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	unsigned offset = ca->mi.bucket_size - ob->sectors_free;
+	int ret;
+
+	if (!bch2_dev_get_ioref(ca, WRITE)) {
+		s->err = -EROFS;
+		return;
+	}
+
+	memset(s->new_stripe.data[block] + (offset << 9),
+	       0,
+	       ob->sectors_free << 9);
+
+	ret = blkdev_issue_zeroout(ca->disk_sb.bdev,
+			ob->bucket * ca->mi.bucket_size + offset,
+			ob->sectors_free,
+			GFP_KERNEL, 0);
+
+	percpu_ref_put(&ca->io_ref);
+
+	if (ret)
+		s->err = ret;
+}
+
 /*
  * data buckets of new stripe all written: create the stripe
  */
@@ -1014,6 +1047,14 @@ static void ec_stripe_create(struct ec_stripe_new *s)
 
 	closure_sync(&s->iodone);
 
+	for (i = 0; i < nr_data; i++)
+		if (s->blocks[i]) {
+			ob = c->open_buckets + s->blocks[i];
+
+			if (ob->sectors_free)
+				zero_out_rest_of_ec_bucket(c, s, i, ob);
+		}
+
 	if (s->err) {
 		if (!bch2_err_matches(s->err, EROFS))
 			bch_err(c, "error creating stripe: error writing data buckets");
@@ -1155,9 +1196,6 @@ void bch2_ec_bucket_written(struct bch_fs *c, struct open_bucket *ob)
 {
 	struct ec_stripe_new *s = ob->ec;
 
-	if (ob->sectors_free)
-		s->err = -1;
-
 	ec_stripe_new_put(c, s);
 }
 
@@ -1398,10 +1436,10 @@ static int new_stripe_alloc_buckets(struct btree_trans *trans, struct ec_stripe_
 					    h->s->nr_parity,
 					    &nr_have_parity,
 					    &have_cache,
+					    BCH_DATA_parity,
 					    h->copygc
 					    ? RESERVE_movinggc
 					    : RESERVE_none,
-					    0,
 					    cl);
 
 		open_bucket_for_each(c, &buckets, ob, i) {
@@ -1427,10 +1465,10 @@ static int new_stripe_alloc_buckets(struct btree_trans *trans, struct ec_stripe_
 					    h->s->nr_data,
 					    &nr_have_data,
 					    &have_cache,
+					    BCH_DATA_user,
 					    h->copygc
 					    ? RESERVE_movinggc
 					    : RESERVE_none,
-					    0,
 					    cl);
 
 		open_bucket_for_each(c, &buckets, ob, i) {
@@ -1486,8 +1524,9 @@ static s64 get_existing_stripe(struct bch_fs *c,
 	return ret;
 }
 
-static int __bch2_ec_stripe_head_reuse(struct bch_fs *c, struct ec_stripe_head *h)
+static int __bch2_ec_stripe_head_reuse(struct btree_trans *trans, struct ec_stripe_head *h)
 {
+	struct bch_fs *c = trans->c;
 	unsigned i;
 	s64 idx;
 	int ret;
@@ -1497,7 +1536,7 @@ static int __bch2_ec_stripe_head_reuse(struct bch_fs *c, struct ec_stripe_head *
 		return -BCH_ERR_ENOSPC_stripe_reuse;
 
 	h->s->have_existing_stripe = true;
-	ret = get_stripe_key(c, idx, &h->s->existing_stripe);
+	ret = get_stripe_key_trans(trans, idx, &h->s->existing_stripe);
 	if (ret) {
 		bch2_fs_fatal_error(c, "error reading stripe key: %i", ret);
 		return ret;
@@ -1626,7 +1665,7 @@ struct ec_stripe_head *bch2_ec_stripe_head_get(struct btree_trans *trans,
 		goto err;
 
 	if (ret && needs_stripe_new)
-		ret = __bch2_ec_stripe_head_reuse(c, h);
+		ret = __bch2_ec_stripe_head_reuse(trans, h);
 	if (ret) {
 		bch_err_ratelimited(c, "failed to get stripe: %s", bch2_err_str(ret));
 		goto err;
@@ -1771,6 +1810,7 @@ void bch2_new_stripes_to_text(struct printbuf *out, struct bch_fs *c)
 void bch2_fs_ec_exit(struct bch_fs *c)
 {
 	struct ec_stripe_head *h;
+	unsigned i;
 
 	while (1) {
 		mutex_lock(&c->ec_stripe_head_lock);
@@ -1782,7 +1822,12 @@ void bch2_fs_ec_exit(struct bch_fs *c)
 		if (!h)
 			break;
 
-		BUG_ON(h->s);
+		if (h->s) {
+			for (i = 0; i < h->s->new_stripe.key.v.nr_blocks; i++)
+				BUG_ON(h->s->blocks[i]);
+
+			kfree(h->s);
+		}
 		kfree(h);
 	}
 
@@ -1801,6 +1846,8 @@ void bch2_fs_ec_init_early(struct bch_fs *c)
 
 int bch2_fs_ec_init(struct bch_fs *c)
 {
+	spin_lock_init(&c->ec_stripes_new_lock);
+
 	return bioset_init(&c->ec_bioset, 1, offsetof(struct ec_bio, bio),
 			   BIOSET_NEED_BVECS);
 }
diff --git a/libbcachefs/extents.c b/libbcachefs/extents.c
index d01cec89..4fc581be 100644
--- a/libbcachefs/extents.c
+++ b/libbcachefs/extents.c
@@ -706,18 +706,6 @@ void bch2_bkey_extent_entry_drop(struct bkey_i *k, union bch_extent_entry *entry
 	k->k.u64s -= extent_entry_u64s(entry);
 }
 
-static inline void __extent_entry_insert(struct bkey_i *k,
-					 union bch_extent_entry *dst,
-					 union bch_extent_entry *new)
-{
-	union bch_extent_entry *end = bkey_val_end(bkey_i_to_s(k));
-
-	memmove_u64s_up_small((u64 *) dst + extent_entry_u64s(new),
-			      dst, (u64 *) end - (u64 *) dst);
-	k->k.u64s += extent_entry_u64s(new);
-	memcpy_u64s_small(dst, new, extent_entry_u64s(new));
-}
-
 void bch2_extent_ptr_decoded_append(struct bkey_i *k,
 				    struct extent_ptr_decoded *p)
 {
@@ -951,6 +939,29 @@ bool bch2_extent_has_ptr(struct bkey_s_c k1, struct extent_ptr_decoded p1,
 	return false;
 }
 
+void bch2_extent_ptr_set_cached(struct bkey_s k, struct bch_extent_ptr *ptr)
+{
+	struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
+	union bch_extent_entry *entry;
+	union bch_extent_entry *ec = NULL;
+
+	bkey_extent_entry_for_each(ptrs, entry) {
+		if (&entry->ptr == ptr) {
+			ptr->cached = true;
+			if (ec)
+				extent_entry_drop(k, ec);
+			return;
+		}
+
+		if (extent_entry_is_stripe_ptr(entry))
+			ec = entry;
+		else if (extent_entry_is_ptr(entry))
+			ec = NULL;
+	}
+
+	BUG();
+}
+
 /*
  * bch_extent_normalize - clean up an extent, dropping stale pointers etc.
  *
@@ -1094,7 +1105,7 @@ int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	unsigned size_ondisk = k.k->size;
 	unsigned nonce = UINT_MAX;
 	unsigned nr_ptrs = 0;
-	bool unwritten = false;
+	bool unwritten = false, have_ec = false, crc_since_last_ptr = false;
 	int ret;
 
 	if (bkey_is_btree_ptr(k.k))
@@ -1130,7 +1141,14 @@ int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
 				return -BCH_ERR_invalid_bkey;
 			}
 
+			if (entry->ptr.cached && have_ec) {
+				prt_printf(err, "cached, erasure coded ptr");
+				return -BCH_ERR_invalid_bkey;
+			}
+
 			unwritten = entry->ptr.unwritten;
+			have_ec = false;
+			crc_since_last_ptr = false;
 			nr_ptrs++;
 			break;
 		case BCH_EXTENT_ENTRY_crc32:
@@ -1164,17 +1182,43 @@ int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
 					return -BCH_ERR_invalid_bkey;
 				}
 			}
+
+			if (crc_since_last_ptr) {
+				prt_printf(err, "redundant crc entry");
+				return -BCH_ERR_invalid_bkey;
+			}
+			crc_since_last_ptr = true;
 			break;
 		case BCH_EXTENT_ENTRY_stripe_ptr:
+			if (have_ec) {
+				prt_printf(err, "redundant stripe entry");
+				return -BCH_ERR_invalid_bkey;
+			}
+			have_ec = true;
 			break;
 		}
 	}
 
+	if (!nr_ptrs) {
+		prt_str(err, "no ptrs");
+		return -BCH_ERR_invalid_bkey;
+	}
+
 	if (nr_ptrs >= BCH_BKEY_PTRS_MAX) {
 		prt_str(err, "too many ptrs");
 		return -BCH_ERR_invalid_bkey;
 	}
 
+	if (crc_since_last_ptr) {
+		prt_printf(err, "redundant crc entry");
+		return -BCH_ERR_invalid_bkey;
+	}
+
+	if (have_ec) {
+		prt_printf(err, "redundant stripe entry");
+		return -BCH_ERR_invalid_bkey;
+	}
+
 	return 0;
 }
 
diff --git a/libbcachefs/extents.h b/libbcachefs/extents.h
index 1d8f3b30..2e37543a 100644
--- a/libbcachefs/extents.h
+++ b/libbcachefs/extents.h
@@ -76,6 +76,18 @@ static inline size_t extent_entry_u64s(const union bch_extent_entry *entry)
 	return extent_entry_bytes(entry) / sizeof(u64);
 }
 
+static inline void __extent_entry_insert(struct bkey_i *k,
+					 union bch_extent_entry *dst,
+					 union bch_extent_entry *new)
+{
+	union bch_extent_entry *end = bkey_val_end(bkey_i_to_s(k));
+
+	memmove_u64s_up_small((u64 *) dst + extent_entry_u64s(new),
+			      dst, (u64 *) end - (u64 *) dst);
+	k->k.u64s += extent_entry_u64s(new);
+	memcpy_u64s_small(dst, new, extent_entry_u64s(new));
+}
+
 static inline bool extent_entry_is_ptr(const union bch_extent_entry *e)
 {
 	return extent_entry_type(e) == BCH_EXTENT_ENTRY_ptr;
@@ -655,6 +667,8 @@ bool bch2_bkey_matches_ptr(struct bch_fs *, struct bkey_s_c,
 bool bch2_extents_match(struct bkey_s_c, struct bkey_s_c);
 bool bch2_extent_has_ptr(struct bkey_s_c, struct extent_ptr_decoded, struct bkey_s_c);
 
+void bch2_extent_ptr_set_cached(struct bkey_s, struct bch_extent_ptr *);
+
 bool bch2_extent_normalize(struct bch_fs *, struct bkey_s);
 void bch2_bkey_ptrs_to_text(struct printbuf *, struct bch_fs *,
 			    struct bkey_s_c);
diff --git a/libbcachefs/io.c b/libbcachefs/io.c
index 64925db2..15ce0657 100644
--- a/libbcachefs/io.c
+++ b/libbcachefs/io.c
@@ -1650,7 +1650,7 @@ static void __bch2_write(struct bch_write_op *op)
 
 	nofs_flags = memalloc_nofs_save();
 
-	if (unlikely(op->opts.nocow)) {
+	if (unlikely(op->opts.nocow && c->opts.nocow_enabled)) {
 		bch2_nocow_write(op);
 		if (op->flags & BCH_WRITE_DONE)
 			goto out_nofs_restore;
diff --git a/libbcachefs/journal.c b/libbcachefs/journal.c
index 957eeece..e0c4f51a 100644
--- a/libbcachefs/journal.c
+++ b/libbcachefs/journal.c
@@ -789,8 +789,7 @@ static int __bch2_set_nr_journal_buckets(struct bch_dev *ca, unsigned nr,
 				break;
 			}
 		} else {
-			ob[nr_got] = bch2_bucket_alloc(c, ca, RESERVE_none,
-					       false, cl);
+			ob[nr_got] = bch2_bucket_alloc(c, ca, RESERVE_none, cl);
 			ret = PTR_ERR_OR_ZERO(ob[nr_got]);
 			if (ret)
 				break;
diff --git a/libbcachefs/keylist.c b/libbcachefs/keylist.c
index 29e51bde..cf5998e5 100644
--- a/libbcachefs/keylist.c
+++ b/libbcachefs/keylist.c
@@ -31,22 +31,6 @@ int bch2_keylist_realloc(struct keylist *l, u64 *inline_u64s,
 	return 0;
 }
 
-void bch2_keylist_add_in_order(struct keylist *l, struct bkey_i *insert)
-{
-	struct bkey_i *where;
-
-	for_each_keylist_key(l, where)
-		if (bpos_lt(insert->k.p, where->k.p))
-			break;
-
-	memmove_u64s_up((u64 *) where + insert->k.u64s,
-			where,
-			((u64 *) l->top) - ((u64 *) where));
-
-	l->top_p += insert->k.u64s;
-	bkey_copy(where, insert);
-}
-
 void bch2_keylist_pop_front(struct keylist *l)
 {
 	l->top_p -= bch2_keylist_front(l)->k.u64s;
diff --git a/libbcachefs/keylist.h b/libbcachefs/keylist.h
index 635efb7e..fe759c70 100644
--- a/libbcachefs/keylist.h
+++ b/libbcachefs/keylist.h
@@ -5,7 +5,6 @@
 #include "keylist_types.h"
 
 int bch2_keylist_realloc(struct keylist *, u64 *, size_t, size_t);
-void bch2_keylist_add_in_order(struct keylist *, struct bkey_i *);
 void bch2_keylist_pop_front(struct keylist *);
 
 static inline void bch2_keylist_init(struct keylist *l, u64 *inline_keys)
diff --git a/libbcachefs/lru.c b/libbcachefs/lru.c
index 9eec12a9..e913b90f 100644
--- a/libbcachefs/lru.c
+++ b/libbcachefs/lru.c
@@ -4,6 +4,7 @@
 #include "alloc_background.h"
 #include "btree_iter.h"
 #include "btree_update.h"
+#include "btree_write_buffer.h"
 #include "error.h"
 #include "lru.h"
 #include "recovery.h"
@@ -101,7 +102,8 @@ static const char * const bch2_lru_types[] = {
 
 static int bch2_check_lru_key(struct btree_trans *trans,
 			      struct btree_iter *lru_iter,
-			      struct bkey_s_c lru_k)
+			      struct bkey_s_c lru_k,
+			      struct bpos *last_flushed_pos)
 {
 	struct bch_fs *c = trans->c;
 	struct btree_iter iter;
@@ -137,19 +139,25 @@ static int bch2_check_lru_key(struct btree_trans *trans,
 		break;
 	}
 
-	if (fsck_err_on(lru_k.k->type != KEY_TYPE_set ||
-			lru_pos_time(lru_k.k->p) != idx, c,
-			"incorrect lru entry: lru %s time %llu\n"
-			"  %s\n"
-			"  for %s",
-			bch2_lru_types[type],
-			lru_pos_time(lru_k.k->p),
-			(bch2_bkey_val_to_text(&buf1, c, lru_k), buf1.buf),
-			(bch2_bkey_val_to_text(&buf2, c, k), buf2.buf))) {
-		ret = bch2_btree_delete_at(trans, lru_iter, 0);
-		if (ret)
-			goto err;
+	if (lru_k.k->type != KEY_TYPE_set ||
+	    lru_pos_time(lru_k.k->p) != idx) {
+		if (!bpos_eq(*last_flushed_pos, lru_k.k->p)) {
+			*last_flushed_pos = lru_k.k->p;
+			ret = bch2_btree_write_buffer_flush_sync(trans) ?:
+				-BCH_ERR_transaction_restart_write_buffer_flush;
+			goto out;
+		}
+
+		if (fsck_err(c, "incorrect lru entry: lru %s time %llu\n"
+			     "  %s\n"
+			     "  for %s",
+			     bch2_lru_types[type],
+			     lru_pos_time(lru_k.k->p),
+			     (bch2_bkey_val_to_text(&buf1, c, lru_k), buf1.buf),
+			     (bch2_bkey_val_to_text(&buf2, c, k), buf2.buf)))
+			ret = bch2_btree_delete_at(trans, lru_iter, 0);
 	}
+out:
 err:
 fsck_err:
 	bch2_trans_iter_exit(trans, &iter);
@@ -163,6 +171,7 @@ int bch2_check_lrus(struct bch_fs *c)
 	struct btree_trans trans;
 	struct btree_iter iter;
 	struct bkey_s_c k;
+	struct bpos last_flushed_pos = POS_MIN;
 	int ret = 0;
 
 	bch2_trans_init(&trans, c, 0, 0);
@@ -170,7 +179,7 @@ int bch2_check_lrus(struct bch_fs *c)
 	ret = for_each_btree_key_commit(&trans, iter,
 			BTREE_ID_lru, POS_MIN, BTREE_ITER_PREFETCH, k,
 			NULL, NULL, BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
-		bch2_check_lru_key(&trans, &iter, k));
+		bch2_check_lru_key(&trans, &iter, k, &last_flushed_pos));
 
 	bch2_trans_exit(&trans);
 	return ret;
diff --git a/libbcachefs/move.c b/libbcachefs/move.c
index 7dac9264..4ef7595f 100644
--- a/libbcachefs/move.c
+++ b/libbcachefs/move.c
@@ -227,7 +227,8 @@ static int bch2_extent_drop_ptrs(struct btree_trans *trans,
 	if (bkey_deleted(&n->k))
 		n->k.size = 0;
 
-	return bch2_trans_update(trans, iter, n, BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) ?:
+	return bch2_trans_relock(trans) ?:
+		bch2_trans_update(trans, iter, n, BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) ?:
 		bch2_trans_commit(trans, NULL, NULL, BTREE_INSERT_NOFAIL);
 }
 
diff --git a/libbcachefs/opts.h b/libbcachefs/opts.h
index 304718a0..76c2691a 100644
--- a/libbcachefs/opts.h
+++ b/libbcachefs/opts.h
@@ -404,6 +404,12 @@ enum opt_type {
 	  NULL,		"Nocow mode: Writes will be done in place when possible.\n"\
 			"Snapshots and reflink will still caused writes to be COW\n"\
 			"Implicitly disables data checksumming, compression and encryption")\
+	x(nocow_enabled,		u8,				\
+	  OPT_FS|OPT_MOUNT,						\
+	  OPT_BOOL(),							\
+	  BCH2_NO_SB_OPT,			true,			\
+	  NULL,		"Enable nocow mode: enables runtime locking in\n"\
+			"data move path needed if nocow will ever be in use\n")\
 	x(no_data_io,			u8,				\
 	  OPT_FS|OPT_MOUNT,						\
 	  OPT_BOOL(),							\
diff --git a/libbcachefs/sysfs.c b/libbcachefs/sysfs.c
index b981c87e..a7582dd4 100644
--- a/libbcachefs/sysfs.c
+++ b/libbcachefs/sysfs.c
@@ -194,6 +194,7 @@ read_attribute(btree_cache);
 read_attribute(btree_key_cache);
 read_attribute(stripes_heap);
 read_attribute(open_buckets);
+read_attribute(open_buckets_partial);
 read_attribute(write_points);
 read_attribute(nocow_lock_table);
 
@@ -455,6 +456,9 @@ SHOW(bch2_fs)
 	if (attr == &sysfs_open_buckets)
 		bch2_open_buckets_to_text(out, c);
 
+	if (attr == &sysfs_open_buckets_partial)
+		bch2_open_buckets_partial_to_text(out, c);
+
 	if (attr == &sysfs_write_points)
 		bch2_write_points_to_text(out, c);
 
@@ -663,6 +667,7 @@ struct attribute *bch2_fs_internal_files[] = {
 	&sysfs_new_stripes,
 	&sysfs_stripes_heap,
 	&sysfs_open_buckets,
+	&sysfs_open_buckets_partial,
 	&sysfs_write_points,
 #ifdef BCH_WRITE_REF_DEBUG
 	&sysfs_write_refs,
diff --git a/linux/blkdev.c b/linux/blkdev.c
index 0a5cedfe..805d55db 100644
--- a/linux/blkdev.c
+++ b/linux/blkdev.c
@@ -118,6 +118,14 @@ int blkdev_issue_discard(struct block_device *bdev,
 	return 0;
 }
 
+int blkdev_issue_zeroout(struct block_device *bdev,
+			 sector_t sector, sector_t nr_sects,
+			 gfp_t gfp_mask, unsigned flags)
+{
+	/* Not yet implemented: */
+	BUG();
+}
+
 unsigned bdev_logical_block_size(struct block_device *bdev)
 {
 	struct stat statbuf;