bcachefs: member helper cleanups

Some renaming for better consistency

bch2_member_exists	-> bch2_member_alive
bch2_dev_exists		-> bch2_member_exists
bch2_dev_exsits2	-> bch2_dev_exists
bch_dev_locked		-> bch2_dev_locked
bch_dev_bkey_exists	-> bch2_dev_bkey_exists

new helper - bch2_dev_safe

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

26 files changed, 131 insertions, 124 deletions

diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
index bcb07fb8fd98..86c0f988d51b 100644
--- a/fs/bcachefs/alloc_background.c
+++ b/fs/bcachefs/alloc_background.c
@@ -576,10 +576,10 @@ int bch2_alloc_read(struct bch_fs *c)
 			 * Not a fsck error because this is checked/repaired by
 			 * bch2_check_alloc_key() which runs later:
 			 */
-			if (!bch2_dev_exists2(c, k.k->p.inode))
+			if (!bch2_dev_exists(c, k.k->p.inode))
 				continue;
 
-			struct bch_dev *ca = bch_dev_bkey_exists(c, k.k->p.inode);
+			struct bch_dev *ca = bch2_dev_bkey_exists(c, k.k->p.inode);
 
 			for (u64 b = max_t(u64, ca->mi.first_bucket, start);
 			     b < min_t(u64, ca->mi.nbuckets, end);
@@ -597,7 +597,7 @@ int bch2_alloc_read(struct bch_fs *c)
 			if (!bch2_dev_bucket_exists(c, k.k->p))
 				continue;
 
-			struct bch_dev *ca = bch_dev_bkey_exists(c, k.k->p.inode);
+			struct bch_dev *ca = bch2_dev_bkey_exists(c, k.k->p.inode);
 
 			struct bch_alloc_v4 a;
 			*bucket_gen(ca, k.k->p.offset) = bch2_alloc_to_v4(k, &a)->gen;
@@ -620,7 +620,7 @@ static int bch2_bucket_do_index(struct btree_trans *trans,
 				bool set)
 {
 	struct bch_fs *c = trans->c;
-	struct bch_dev *ca = bch_dev_bkey_exists(c, alloc_k.k->p.inode);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, alloc_k.k->p.inode);
 	struct btree_iter iter;
 	struct bkey_s_c old;
 	struct bkey_i *k;
@@ -733,7 +733,7 @@ int bch2_trigger_alloc(struct btree_trans *trans,
 				       "alloc key for invalid device or bucket"))
 		return -EIO;
 
-	struct bch_dev *ca = bch_dev_bkey_exists(c, new.k->p.inode);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, new.k->p.inode);
 
 	struct bch_alloc_v4 old_a_convert;
 	const struct bch_alloc_v4 *old_a = bch2_alloc_to_v4(old, &old_a_convert);
@@ -781,7 +781,7 @@ int bch2_trigger_alloc(struct btree_trans *trans,
 		}
 
 		new_a->fragmentation_lru = alloc_lru_idx_fragmentation(*new_a,
-						bch_dev_bkey_exists(c, new.k->p.inode));
+						bch2_dev_bkey_exists(c, new.k->p.inode));
 		if (old_a->fragmentation_lru != new_a->fragmentation_lru) {
 			ret = bch2_lru_change(trans,
 					BCH_LRU_FRAGMENTATION_START,
@@ -955,8 +955,8 @@ static bool next_bucket(struct bch_fs *c, struct bpos *bucket)
 	if (bch2_dev_bucket_exists(c, *bucket))
 		return true;
 
-	if (bch2_dev_exists2(c, bucket->inode)) {
-		ca = bch_dev_bkey_exists(c, bucket->inode);
+	if (bch2_dev_exists(c, bucket->inode)) {
+		ca = bch2_dev_bkey_exists(c, bucket->inode);
 
 		if (bucket->offset < ca->mi.first_bucket) {
 			bucket->offset = ca->mi.first_bucket;
@@ -997,7 +997,7 @@ again:
 		}
 
 		if (!bch2_dev_bucket_exists(c, k.k->p)) {
-			struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
+			struct bch_dev *ca = bch2_dev_bkey_exists(c, bucket.inode);
 
 			bch2_key_resize(hole, ca->mi.nbuckets - bucket.offset);
 		}
@@ -1030,7 +1030,7 @@ int bch2_check_alloc_key(struct btree_trans *trans,
 			alloc_k.k->p.inode, alloc_k.k->p.offset))
 		return bch2_btree_delete_at(trans, alloc_iter, 0);
 
-	ca = bch_dev_bkey_exists(c, alloc_k.k->p.inode);
+	ca = bch2_dev_bkey_exists(c, alloc_k.k->p.inode);
 	if (!ca->mi.freespace_initialized)
 		return 0;
 
@@ -1149,7 +1149,7 @@ int bch2_check_alloc_hole_freespace(struct btree_trans *trans,
 	struct printbuf buf = PRINTBUF;
 	int ret;
 
-	ca = bch_dev_bkey_exists(c, start.inode);
+	ca = bch2_dev_bkey_exists(c, start.inode);
 	if (!ca->mi.freespace_initialized)
 		return 0;
 
@@ -1339,7 +1339,7 @@ int bch2_check_bucket_gens_key(struct btree_trans *trans,
 	bkey_reassemble(&g.k_i, k);
 
 	/* if no bch_dev, skip out whether we repair or not */
-	dev_exists = bch2_dev_exists2(c, k.k->p.inode);
+	dev_exists = bch2_dev_exists(c, k.k->p.inode);
 	if (!dev_exists) {
 		if (fsck_err_on(!dev_exists, c,
 				bucket_gens_to_invalid_dev,
@@ -1350,7 +1350,7 @@ int bch2_check_bucket_gens_key(struct btree_trans *trans,
 		goto out;
 	}
 
-	ca = bch_dev_bkey_exists(c, k.k->p.inode);
+	ca = bch2_dev_bkey_exists(c, k.k->p.inode);
 	if (fsck_err_on(end <= ca->mi.first_bucket ||
 			start >= ca->mi.nbuckets, c,
 			bucket_gens_to_invalid_buckets,
@@ -1669,7 +1669,7 @@ static int bch2_discard_one_bucket(struct btree_trans *trans,
 	bool discard_locked = false;
 	int ret = 0;
 
-	ca = bch_dev_bkey_exists(c, pos.inode);
+	ca = bch2_dev_bkey_exists(c, pos.inode);
 
 	if (!percpu_ref_tryget(&ca->io_ref)) {
 		bch2_btree_iter_set_pos(need_discard_iter, POS(pos.inode + 1, 0));
@@ -1852,7 +1852,7 @@ static void bch2_do_discards_fast_work(struct work_struct *work)
 			if (i->snapshot)
 				continue;
 
-			ca = bch_dev_bkey_exists(c, i->inode);
+			ca = bch2_dev_bkey_exists(c, i->inode);
 
 			if (!percpu_ref_tryget(&ca->io_ref)) {
 				darray_remove_item(&c->discard_buckets_in_flight, i);
@@ -1893,7 +1893,7 @@ static void bch2_do_discards_fast_work(struct work_struct *work)
 
 static void bch2_discard_one_bucket_fast(struct bch_fs *c, struct bpos bucket)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, bucket.inode);
 
 	if (!percpu_ref_is_dying(&ca->io_ref) &&
 	    !discard_in_flight_add(c, bucket) &&
diff --git a/fs/bcachefs/alloc_background.h b/fs/bcachefs/alloc_background.h
index 5d57b43c63ef..f9589a2c7a1f 100644
--- a/fs/bcachefs/alloc_background.h
+++ b/fs/bcachefs/alloc_background.h
@@ -17,10 +17,10 @@ static inline bool bch2_dev_bucket_exists(struct bch_fs *c, struct bpos pos)
 {
 	struct bch_dev *ca;
 
-	if (!bch2_dev_exists2(c, pos.inode))
+	if (!bch2_dev_exists(c, pos.inode))
 		return false;
 
-	ca = bch_dev_bkey_exists(c, pos.inode);
+	ca = bch2_dev_bkey_exists(c, pos.inode);
 	return bucket_valid(ca, pos.offset);
 }
 
diff --git a/fs/bcachefs/alloc_foreground.c b/fs/bcachefs/alloc_foreground.c
index b68e1fd782f3..df4439a38df5 100644
--- a/fs/bcachefs/alloc_foreground.c
+++ b/fs/bcachefs/alloc_foreground.c
@@ -100,7 +100,7 @@ static void bch2_open_bucket_hash_remove(struct bch_fs *c, struct open_bucket *o
 
 void __bch2_open_bucket_put(struct bch_fs *c, struct open_bucket *ob)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ob->dev);
 
 	if (ob->ec) {
 		ec_stripe_new_put(c, ob->ec, STRIPE_REF_io);
@@ -679,7 +679,7 @@ static int add_new_bucket(struct bch_fs *c,
 			   struct open_bucket *ob)
 {
 	unsigned durability =
-		bch_dev_bkey_exists(c, ob->dev)->mi.durability;
+		bch2_dev_bkey_exists(c, ob->dev)->mi.durability;
 
 	BUG_ON(*nr_effective >= nr_replicas);
 
@@ -836,7 +836,7 @@ static bool want_bucket(struct bch_fs *c,
 			bool *have_cache, bool ec,
 			struct open_bucket *ob)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ob->dev);
 
 	if (!test_bit(ob->dev, devs_may_alloc->d))
 		return false;
@@ -906,7 +906,7 @@ static int bucket_alloc_set_partial(struct bch_fs *c,
 		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 *ca = bch2_dev_bkey_exists(c, ob->dev);
 			struct bch_dev_usage usage;
 			u64 avail;
 
@@ -1291,7 +1291,7 @@ deallocate_extra_replicas(struct bch_fs *c,
 	unsigned i;
 
 	open_bucket_for_each(c, ptrs, ob, i) {
-		unsigned d = bch_dev_bkey_exists(c, ob->dev)->mi.durability;
+		unsigned d = bch2_dev_bkey_exists(c, ob->dev)->mi.durability;
 
 		if (d && d <= extra_replicas) {
 			extra_replicas -= d;
@@ -1444,7 +1444,7 @@ err:
 
 struct bch_extent_ptr bch2_ob_ptr(struct bch_fs *c, struct open_bucket *ob)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ob->dev);
 
 	return (struct bch_extent_ptr) {
 		.type	= 1 << BCH_EXTENT_ENTRY_ptr,
@@ -1520,7 +1520,7 @@ void bch2_fs_allocator_foreground_init(struct bch_fs *c)
 
 static void bch2_open_bucket_to_text(struct printbuf *out, struct bch_fs *c, struct open_bucket *ob)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ob->dev);
 	unsigned data_type = ob->data_type;
 	barrier(); /* READ_ONCE() doesn't work on bitfields */
 
diff --git a/fs/bcachefs/alloc_foreground.h b/fs/bcachefs/alloc_foreground.h
index 7aaeec44c746..c101b2c36743 100644
--- a/fs/bcachefs/alloc_foreground.h
+++ b/fs/bcachefs/alloc_foreground.h
@@ -184,7 +184,7 @@ bch2_alloc_sectors_append_ptrs_inlined(struct bch_fs *c, struct write_point *wp,
 	wp->sectors_allocated	+= sectors;
 
 	open_bucket_for_each(c, &wp->ptrs, ob, i) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, ob->dev);
 		struct bch_extent_ptr ptr = bch2_ob_ptr(c, ob);
 
 		ptr.cached = cached ||
diff --git a/fs/bcachefs/backpointers.c b/fs/bcachefs/backpointers.c
index 6e76ff890c3f..8abfac81ac70 100644
--- a/fs/bcachefs/backpointers.c
+++ b/fs/bcachefs/backpointers.c
@@ -46,7 +46,7 @@ int bch2_backpointer_invalid(struct bch_fs *c, struct bkey_s_c k,
 	struct bkey_s_c_backpointer bp = bkey_s_c_to_backpointer(k);
 
 	/* these will be caught by fsck */
-	if (!bch2_dev_exists2(c, bp.k->p.inode))
+	if (!bch2_dev_exists(c, bp.k->p.inode))
 		return 0;
 
 	struct bpos bucket = bp_pos_to_bucket(c, bp.k->p);
@@ -73,7 +73,7 @@ void bch2_backpointer_to_text(struct printbuf *out, const struct bch_backpointer
 
 void bch2_backpointer_k_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
 {
-	if (bch2_dev_exists2(c, k.k->p.inode)) {
+	if (bch2_dev_exists(c, k.k->p.inode)) {
 		prt_str(out, "bucket=");
 		bch2_bpos_to_text(out, bp_pos_to_bucket(c, k.k->p));
 		prt_str(out, " ");
@@ -364,7 +364,7 @@ static int bch2_check_btree_backpointer(struct btree_trans *trans, struct btree_
 	struct printbuf buf = PRINTBUF;
 	int ret = 0;
 
-	if (fsck_err_on(!bch2_dev_exists2(c, k.k->p.inode), c,
+	if (fsck_err_on(!bch2_dev_exists(c, k.k->p.inode), c,
 			backpointer_to_missing_device,
 			"backpointer for missing device:\n%s",
 			(bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
@@ -457,7 +457,7 @@ found:
 
 	bytes = p.crc.compressed_size << 9;
 
-	struct bch_dev *ca = bch_dev_bkey_exists(c, dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, dev);
 	if (!bch2_dev_get_ioref(ca, READ))
 		return false;
 
diff --git a/fs/bcachefs/backpointers.h b/fs/bcachefs/backpointers.h
index da012ca7daee..3538499c4b5c 100644
--- a/fs/bcachefs/backpointers.h
+++ b/fs/bcachefs/backpointers.h
@@ -39,7 +39,7 @@ void bch2_backpointer_swab(struct bkey_s);
 static inline struct bpos bp_pos_to_bucket(const struct bch_fs *c,
 					   struct bpos bp_pos)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, bp_pos.inode);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, bp_pos.inode);
 	u64 bucket_sector = bp_pos.offset >> MAX_EXTENT_COMPRESS_RATIO_SHIFT;
 
 	return POS(bp_pos.inode, sector_to_bucket(ca, bucket_sector));
@@ -52,7 +52,7 @@ static inline struct bpos bucket_pos_to_bp(const struct bch_fs *c,
 					   struct bpos bucket,
 					   u64 bucket_offset)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, bucket.inode);
 	struct bpos ret;
 
 	ret = POS(bucket.inode,
diff --git a/fs/bcachefs/bcachefs.h b/fs/bcachefs/bcachefs.h
index 3dad47533491..7562446f2d2a 100644
--- a/fs/bcachefs/bcachefs.h
+++ b/fs/bcachefs/bcachefs.h
@@ -1253,11 +1253,6 @@ static inline s64 bch2_current_time(const struct bch_fs *c)
 	return timespec_to_bch2_time(c, now);
 }
 
-static inline bool bch2_dev_exists2(const struct bch_fs *c, unsigned dev)
-{
-	return dev < c->sb.nr_devices && c->devs[dev];
-}
-
 static inline struct stdio_redirect *bch2_fs_stdio_redirect(struct bch_fs *c)
 {
 	struct stdio_redirect *stdio = c->stdio;
diff --git a/fs/bcachefs/btree_gc.c b/fs/bcachefs/btree_gc.c
index cd34a09bd3c9..10c41cf89212 100644
--- a/fs/bcachefs/btree_gc.c
+++ b/fs/bcachefs/btree_gc.c
@@ -597,7 +597,7 @@ static int bch2_check_fix_ptrs(struct btree_trans *trans, enum btree_id btree_id
 	 * use check_bucket_ref here
 	 */
 	bkey_for_each_ptr_decode(k->k, ptrs_c, p, entry_c) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, p.ptr.dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, p.ptr.dev);
 		struct bucket *g = PTR_GC_BUCKET(ca, &p.ptr);
 		enum bch_data_type data_type = bch2_bkey_ptr_data_type(*k, p, entry_c);
 
@@ -730,7 +730,7 @@ static int bch2_check_fix_ptrs(struct btree_trans *trans, enum btree_id btree_id
 			 */
 			struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(new));
 			bkey_for_each_ptr(ptrs, ptr) {
-				struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+				struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 				struct bucket *g = PTR_GC_BUCKET(ca, ptr);
 
 				ptr->gen = g->gen;
@@ -741,7 +741,7 @@ static int bch2_check_fix_ptrs(struct btree_trans *trans, enum btree_id btree_id
 restart_drop_ptrs:
 			ptrs = bch2_bkey_ptrs(bkey_i_to_s(new));
 			bkey_for_each_ptr_decode(bkey_i_to_s(new).k, ptrs, p, entry) {
-				struct bch_dev *ca = bch_dev_bkey_exists(c, p.ptr.dev);
+				struct bch_dev *ca = bch2_dev_bkey_exists(c, p.ptr.dev);
 				struct bucket *g = PTR_GC_BUCKET(ca, &p.ptr);
 				enum bch_data_type data_type = bch2_bkey_ptr_data_type(bkey_i_to_s_c(new), p, entry);
 
@@ -1202,7 +1202,7 @@ static int bch2_alloc_write_key(struct btree_trans *trans,
 				struct bkey_s_c k)
 {
 	struct bch_fs *c = trans->c;
-	struct bch_dev *ca = bch_dev_bkey_exists(c, iter->pos.inode);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, iter->pos.inode);
 	struct bucket old_gc, gc, *b;
 	struct bkey_i_alloc_v4 *a;
 	struct bch_alloc_v4 old_convert, new;
@@ -1338,7 +1338,7 @@ static int bch2_gc_alloc_start(struct bch_fs *c)
 	int ret = bch2_trans_run(c,
 		for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
 					 BTREE_ITER_prefetch, k, ({
-			struct bch_dev *ca = bch_dev_bkey_exists(c, k.k->p.inode);
+			struct bch_dev *ca = bch2_dev_bkey_exists(c, k.k->p.inode);
 			struct bucket *g = gc_bucket(ca, k.k->p.offset);
 
 			struct bch_alloc_v4 a_convert;
@@ -1657,7 +1657,7 @@ static int gc_btree_gens_key(struct btree_trans *trans,
 
 	percpu_down_read(&c->mark_lock);
 	bkey_for_each_ptr(ptrs, ptr) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 
 		if (ptr_stale(ca, ptr) > 16) {
 			percpu_up_read(&c->mark_lock);
@@ -1666,7 +1666,7 @@ static int gc_btree_gens_key(struct btree_trans *trans,
 	}
 
 	bkey_for_each_ptr(ptrs, ptr) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 		u8 *gen = &ca->oldest_gen[PTR_BUCKET_NR(ca, ptr)];
 
 		if (gen_after(*gen, ptr->gen))
@@ -1687,7 +1687,7 @@ update:
 static int bch2_alloc_write_oldest_gen(struct btree_trans *trans, struct btree_iter *iter,
 				       struct bkey_s_c k)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(trans->c, iter->pos.inode);
+	struct bch_dev *ca = bch2_dev_bkey_exists(trans->c, iter->pos.inode);
 	struct bch_alloc_v4 a_convert;
 	const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert);
 	struct bkey_i_alloc_v4 *a_mut;
diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
index 7e03923be95a..12c14b941cc9 100644
--- a/fs/bcachefs/btree_io.c
+++ b/fs/bcachefs/btree_io.c
@@ -1265,7 +1265,7 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 	btree_node_reset_sib_u64s(b);
 
 	bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&b->key)), ptr) {
-		struct bch_dev *ca2 = bch_dev_bkey_exists(c, ptr->dev);
+		struct bch_dev *ca2 = bch2_dev_bkey_exists(c, ptr->dev);
 
 		if (ca2->mi.state != BCH_MEMBER_STATE_rw)
 			set_btree_node_need_rewrite(b);
@@ -1295,7 +1295,7 @@ static void btree_node_read_work(struct work_struct *work)
 		container_of(work, struct btree_read_bio, work);
 	struct bch_fs *c	= rb->c;
 	struct btree *b		= rb->b;
-	struct bch_dev *ca	= bch_dev_bkey_exists(c, rb->pick.ptr.dev);
+	struct bch_dev *ca	= bch2_dev_bkey_exists(c, rb->pick.ptr.dev);
 	struct bio *bio		= &rb->bio;
 	struct bch_io_failures failed = { .nr = 0 };
 	struct printbuf buf = PRINTBUF;
@@ -1307,7 +1307,7 @@ static void btree_node_read_work(struct work_struct *work)
 	while (1) {
 		retry = true;
 		bch_info(c, "retrying read");
-		ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
+		ca = bch2_dev_bkey_exists(c, rb->pick.ptr.dev);
 		rb->have_ioref		= bch2_dev_get_ioref(ca, READ);
 		bio_reset(bio, NULL, REQ_OP_READ|REQ_SYNC|REQ_META);
 		bio->bi_iter.bi_sector	= rb->pick.ptr.offset;
@@ -1378,7 +1378,7 @@ static void btree_node_read_endio(struct bio *bio)
 	struct bch_fs *c	= rb->c;
 
 	if (rb->have_ioref) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, rb->pick.ptr.dev);
 
 		bch2_latency_acct(ca, rb->start_time, READ);
 	}
@@ -1575,7 +1575,7 @@ static void btree_node_read_all_replicas_endio(struct bio *bio)
 	struct btree_node_read_all *ra = rb->ra;
 
 	if (rb->have_ioref) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, rb->pick.ptr.dev);
 
 		bch2_latency_acct(ca, rb->start_time, READ);
 	}
@@ -1617,7 +1617,7 @@ static int btree_node_read_all_replicas(struct bch_fs *c, struct btree *b, bool
 
 	i = 0;
 	bkey_for_each_ptr_decode(k.k, ptrs, pick, entry) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, pick.ptr.dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, pick.ptr.dev);
 		struct btree_read_bio *rb =
 			container_of(ra->bio[i], struct btree_read_bio, bio);
 		rb->c			= c;
@@ -1694,7 +1694,7 @@ void bch2_btree_node_read(struct btree_trans *trans, struct btree *b,
 		return;
 	}
 
-	ca = bch_dev_bkey_exists(c, pick.ptr.dev);
+	ca = bch2_dev_bkey_exists(c, pick.ptr.dev);
 
 	bio = bio_alloc_bioset(NULL,
 			       buf_pages(b->data, btree_buf_bytes(b)),
@@ -1911,7 +1911,7 @@ static void btree_node_write_endio(struct bio *bio)
 	struct btree_write_bio *wb	= container_of(orig, struct btree_write_bio, wbio);
 	struct bch_fs *c		= wbio->c;
 	struct btree *b			= wbio->bio.bi_private;
-	struct bch_dev *ca		= bch_dev_bkey_exists(c, wbio->dev);
+	struct bch_dev *ca		= bch2_dev_bkey_exists(c, wbio->dev);
 	unsigned long flags;
 
 	if (wbio->have_ioref)
diff --git a/fs/bcachefs/buckets.c b/fs/bcachefs/buckets.c
index ece12aa4b716..ff1f319cd722 100644
--- a/fs/bcachefs/buckets.c
+++ b/fs/bcachefs/buckets.c
@@ -493,7 +493,7 @@ int bch2_check_bucket_ref(struct btree_trans *trans,
 			  u32 bucket_sectors)
 {
 	struct bch_fs *c = trans->c;
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 	size_t bucket_nr = PTR_BUCKET_NR(ca, ptr);
 	struct printbuf buf = PRINTBUF;
 	int ret = 0;
@@ -788,7 +788,7 @@ static int bch2_trigger_pointer(struct btree_trans *trans,
 
 	if (flags & BTREE_TRIGGER_gc) {
 		struct bch_fs *c = trans->c;
-		struct bch_dev *ca = bch_dev_bkey_exists(c, p.ptr.dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, p.ptr.dev);
 		enum bch_data_type data_type = bch2_bkey_ptr_data_type(k, p, entry);
 
 		percpu_down_read(&c->mark_lock);
diff --git a/fs/bcachefs/buckets.h b/fs/bcachefs/buckets.h
index 97b4bf8961e2..a88b9033349f 100644
--- a/fs/bcachefs/buckets.h
+++ b/fs/bcachefs/buckets.h
@@ -128,7 +128,7 @@ static inline size_t PTR_BUCKET_NR(const struct bch_dev *ca,
 static inline struct bpos PTR_BUCKET_POS(const struct bch_fs *c,
 				   const struct bch_extent_ptr *ptr)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 
 	return POS(ptr->dev, PTR_BUCKET_NR(ca, ptr));
 }
@@ -137,7 +137,7 @@ static inline struct bpos PTR_BUCKET_POS_OFFSET(const struct bch_fs *c,
 						const struct bch_extent_ptr *ptr,
 						u32 *bucket_offset)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 
 	return POS(ptr->dev, sector_to_bucket_and_offset(ca, ptr->offset, bucket_offset));
 }
diff --git a/fs/bcachefs/data_update.c b/fs/bcachefs/data_update.c
index 3c0f0801468e..cae4e4eb5329 100644
--- a/fs/bcachefs/data_update.c
+++ b/fs/bcachefs/data_update.c
@@ -360,7 +360,7 @@ void bch2_data_update_exit(struct data_update *update)
 		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);
+		percpu_ref_put(&bch2_dev_bkey_exists(c, ptr->dev)->ref);
 	}
 
 	bch2_bkey_buf_exit(&update->k, c);
@@ -540,7 +540,7 @@ int bch2_data_update_init(struct btree_trans *trans,
 	m->op.watermark		= m->data_opts.btree_insert_flags & BCH_WATERMARK_MASK;
 
 	bkey_for_each_ptr(ptrs, ptr)
-		percpu_ref_get(&bch_dev_bkey_exists(c, ptr->dev)->ref);
+		percpu_ref_get(&bch2_dev_bkey_exists(c, ptr->dev)->ref);
 
 	unsigned durability_have = 0, durability_removing = 0;
 
@@ -652,7 +652,7 @@ err:
 		if ((1U << i) & ptrs_locked)
 			bch2_bucket_nocow_unlock(&c->nocow_locks,
 						 PTR_BUCKET_POS(c, &p.ptr), 0);
-		percpu_ref_put(&bch_dev_bkey_exists(c, p.ptr.dev)->ref);
+		percpu_ref_put(&bch2_dev_bkey_exists(c, p.ptr.dev)->ref);
 		i++;
 	}
 
diff --git a/fs/bcachefs/debug.c b/fs/bcachefs/debug.c
index 8310eff12a17..b5aa4e5b224b 100644
--- a/fs/bcachefs/debug.c
+++ b/fs/bcachefs/debug.c
@@ -37,7 +37,7 @@ static bool bch2_btree_verify_replica(struct bch_fs *c, struct btree *b,
 	struct btree_node *n_ondisk = c->verify_ondisk;
 	struct btree_node *n_sorted = c->verify_data->data;
 	struct bset *sorted, *inmemory = &b->data->keys;
-	struct bch_dev *ca = bch_dev_bkey_exists(c, pick.ptr.dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, pick.ptr.dev);
 	struct bio *bio;
 	bool failed = false, saw_error = false;
 
@@ -194,7 +194,7 @@ void bch2_btree_node_ondisk_to_text(struct printbuf *out, struct bch_fs *c,
 		return;
 	}
 
-	ca = bch_dev_bkey_exists(c, pick.ptr.dev);
+	ca = bch2_dev_bkey_exists(c, pick.ptr.dev);
 	if (!bch2_dev_get_ioref(ca, READ)) {
 		prt_printf(out, "error getting device to read from: not online\n");
 		return;
diff --git a/fs/bcachefs/disk_groups.c b/fs/bcachefs/disk_groups.c
index 06a7df529b40..04b6aa414476 100644
--- a/fs/bcachefs/disk_groups.c
+++ b/fs/bcachefs/disk_groups.c
@@ -177,7 +177,7 @@ int bch2_sb_disk_groups_to_cpu(struct bch_fs *c)
 		struct bch_member m = bch2_sb_member_get(c->disk_sb.sb, i);
 		struct bch_disk_group_cpu *dst;
 
-		if (!bch2_member_exists(&m))
+		if (!bch2_member_alive(&m))
 			continue;
 
 		g = BCH_MEMBER_GROUP(&m);
@@ -588,7 +588,7 @@ static void bch2_target_to_text_sb(struct printbuf *out, struct bch_sb *sb, unsi
 	case TARGET_DEV: {
 		struct bch_member m = bch2_sb_member_get(sb, t.dev);
 
-		if (bch2_dev_exists(sb, t.dev)) {
+		if (bch2_member_exists(sb, t.dev)) {
 			prt_printf(out, "Device ");
 			pr_uuid(out, m.uuid.b);
 			prt_printf(out, " (%u)", t.dev);
diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c
index 86999ed80439..97ed598a55a5 100644
--- a/fs/bcachefs/ec.c
+++ b/fs/bcachefs/ec.c
@@ -253,7 +253,7 @@ static int mark_stripe_bucket(struct btree_trans *trans,
 	enum bch_data_type data_type = parity ? BCH_DATA_parity : BCH_DATA_stripe;
 	s64 sectors = parity ? le16_to_cpu(s->sectors) : 0;
 	const struct bch_extent_ptr *ptr = s->ptrs + ptr_idx;
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 	struct bucket old, new, *g;
 	struct printbuf buf = PRINTBUF;
 	int ret = 0;
@@ -609,7 +609,7 @@ static void ec_validate_checksums(struct bch_fs *c, struct ec_stripe_buf *buf)
 
 			if (bch2_crc_cmp(want, got)) {
 				struct printbuf err = PRINTBUF;
-				struct bch_dev *ca = bch_dev_bkey_exists(c, v->ptrs[i].dev);
+				struct bch_dev *ca = bch2_dev_bkey_exists(c, v->ptrs[i].dev);
 
 				prt_str(&err, "stripe ");
 				bch2_csum_err_msg(&err, v->csum_type, want, got);
@@ -705,7 +705,7 @@ static void ec_block_io(struct bch_fs *c, struct ec_stripe_buf *buf,
 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
 	unsigned offset = 0, bytes = buf->size << 9;
 	struct bch_extent_ptr *ptr = &v->ptrs[idx];
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 	enum bch_data_type data_type = idx < v->nr_blocks - v->nr_redundant
 		? BCH_DATA_user
 		: BCH_DATA_parity;
@@ -1321,7 +1321,7 @@ static void zero_out_rest_of_ec_bucket(struct bch_fs *c,
 				       unsigned block,
 				       struct open_bucket *ob)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ob->dev);
 	unsigned offset = ca->mi.bucket_size - ob->sectors_free;
 	int ret;
 
@@ -1527,7 +1527,7 @@ void *bch2_writepoint_ec_buf(struct bch_fs *c, struct write_point *wp)
 
 	BUG_ON(!ob->ec->new_stripe.data[ob->ec_idx]);
 
-	ca	= bch_dev_bkey_exists(c, ob->dev);
+	ca	= bch2_dev_bkey_exists(c, ob->dev);
 	offset	= ca->mi.bucket_size - ob->sectors_free;
 
 	return ob->ec->new_stripe.data[ob->ec_idx] + (offset << 9);
diff --git a/fs/bcachefs/extents.c b/fs/bcachefs/extents.c
index e9db8f6d6bc1..cb8d52436ab1 100644
--- a/fs/bcachefs/extents.c
+++ b/fs/bcachefs/extents.c
@@ -79,8 +79,8 @@ static inline bool ptr_better(struct bch_fs *c,
 			      const struct extent_ptr_decoded p2)
 {
 	if (likely(!p1.idx && !p2.idx)) {
-		struct bch_dev *dev1 = bch_dev_bkey_exists(c, p1.ptr.dev);
-		struct bch_dev *dev2 = bch_dev_bkey_exists(c, p2.ptr.dev);
+		struct bch_dev *dev1 = bch2_dev_bkey_exists(c, p1.ptr.dev);
+		struct bch_dev *dev2 = bch2_dev_bkey_exists(c, p2.ptr.dev);
 
 		u64 l1 = atomic64_read(&dev1->cur_latency[READ]);
 		u64 l2 = atomic64_read(&dev2->cur_latency[READ]);
@@ -123,7 +123,7 @@ int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
 		if (p.ptr.unwritten)
 			return 0;
 
-		ca = bch_dev_bkey_exists(c, p.ptr.dev);
+		ca = bch2_dev_bkey_exists(c, p.ptr.dev);
 
 		/*
 		 * If there are any dirty pointers it's an error if we can't
@@ -278,7 +278,7 @@ bool bch2_extent_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r)
 			return false;
 
 		/* Extents may not straddle buckets: */
-		ca = bch_dev_bkey_exists(c, lp.ptr.dev);
+		ca = bch2_dev_bkey_exists(c, lp.ptr.dev);
 		if (PTR_BUCKET_NR(ca, &lp.ptr) != PTR_BUCKET_NR(ca, &rp.ptr))
 			return false;
 
@@ -667,14 +667,14 @@ static inline unsigned __extent_ptr_durability(struct bch_dev *ca, struct extent
 
 unsigned bch2_extent_ptr_desired_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, p->ptr.dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, p->ptr.dev);
 
 	return __extent_ptr_durability(ca, p);
 }
 
 unsigned bch2_extent_ptr_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, p->ptr.dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, p->ptr.dev);
 
 	if (ca->mi.state == BCH_MEMBER_STATE_failed)
 		return 0;
@@ -864,7 +864,7 @@ bool bch2_bkey_has_target(struct bch_fs *c, struct bkey_s_c k, unsigned target)
 	bkey_for_each_ptr(ptrs, ptr)
 		if (bch2_dev_in_target(c, ptr->dev, target) &&
 		    (!ptr->cached ||
-		     !ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr)))
+		     !ptr_stale(bch2_dev_bkey_exists(c, ptr->dev), ptr)))
 			return true;
 
 	return false;
@@ -973,17 +973,16 @@ bool bch2_extent_normalize(struct bch_fs *c, struct bkey_s k)
 
 	bch2_bkey_drop_ptrs(k, ptr,
 		ptr->cached &&
-		ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr));
+		ptr_stale(bch2_dev_bkey_exists(c, ptr->dev), ptr));
 
 	return bkey_deleted(k.k);
 }
 
 void bch2_extent_ptr_to_text(struct printbuf *out, struct bch_fs *c, const struct bch_extent_ptr *ptr)
 {
-	struct bch_dev *ca = c && ptr->dev < c->sb.nr_devices && c->devs[ptr->dev]
-		? bch_dev_bkey_exists(c, ptr->dev)
-		: NULL;
-
+	out->atomic++;
+	rcu_read_lock();
+	struct bch_dev *ca = bch2_dev_safe(c, ptr->dev);
 	if (!ca) {
 		prt_printf(out, "ptr: %u:%llu gen %u%s", ptr->dev,
 			   (u64) ptr->offset, ptr->gen,
@@ -1001,6 +1000,8 @@ void bch2_extent_ptr_to_text(struct printbuf *out, struct bch_fs *c, const struc
 		if (bucket_valid(ca, b) && ptr_stale(ca, ptr))
 			prt_printf(out, " stale");
 	}
+	rcu_read_unlock();
+	--out->atomic;
 }
 
 void bch2_bkey_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
@@ -1079,7 +1080,7 @@ static int extent_ptr_invalid(struct bch_fs *c,
 	struct bch_dev *ca;
 	int ret = 0;
 
-	if (!bch2_dev_exists2(c, ptr->dev)) {
+	if (!bch2_dev_exists(c, ptr->dev)) {
 		/*
 		 * If we're in the write path this key might have already been
 		 * overwritten, and we could be seeing a device that doesn't
@@ -1092,7 +1093,7 @@ static int extent_ptr_invalid(struct bch_fs *c,
 			   "pointer to invalid device (%u)", ptr->dev);
 	}
 
-	ca = bch_dev_bkey_exists(c, ptr->dev);
+	ca = bch2_dev_bkey_exists(c, ptr->dev);
 	bkey_for_each_ptr(ptrs, ptr2)
 		bkey_fsck_err_on(ptr != ptr2 && ptr->dev == ptr2->dev, c, err,
 				 ptr_to_duplicate_device,
diff --git a/fs/bcachefs/io_read.c b/fs/bcachefs/io_read.c
index 475ab6c02dd1..af9bd7c45f21 100644
--- a/fs/bcachefs/io_read.c
+++ b/fs/bcachefs/io_read.c
@@ -541,7 +541,7 @@ static void __bch2_read_endio(struct work_struct *work)
 	struct bch_read_bio *rbio =
 		container_of(work, struct bch_read_bio, work);
 	struct bch_fs *c	= rbio->c;
-	struct bch_dev *ca	= bch_dev_bkey_exists(c, rbio->pick.ptr.dev);
+	struct bch_dev *ca	= bch2_dev_bkey_exists(c, rbio->pick.ptr.dev);
 	struct bio *src		= &rbio->bio;
 	struct bio *dst		= &bch2_rbio_parent(rbio)->bio;
 	struct bvec_iter dst_iter = rbio->bvec_iter;
@@ -675,7 +675,7 @@ static void bch2_read_endio(struct bio *bio)
 	struct bch_read_bio *rbio =
 		container_of(bio, struct bch_read_bio, bio);
 	struct bch_fs *c	= rbio->c;
-	struct bch_dev *ca	= bch_dev_bkey_exists(c, rbio->pick.ptr.dev);
+	struct bch_dev *ca	= bch2_dev_bkey_exists(c, rbio->pick.ptr.dev);
 	struct workqueue_struct *wq = NULL;
 	enum rbio_context context = RBIO_CONTEXT_NULL;
 
@@ -762,7 +762,7 @@ static noinline void read_from_stale_dirty_pointer(struct btree_trans *trans,
 						   struct bch_extent_ptr ptr)
 {
 	struct bch_fs *c = trans->c;
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr.dev);
+	struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr.dev);
 	struct btree_iter iter;
 	struct printbuf buf = PRINTBUF;
 	int ret;
@@ -831,7 +831,7 @@ retry_pick:
 		goto err;
 	}
 
-	ca = bch_dev_bkey_exists(c, pick.ptr.dev);
+	ca = bch2_dev_bkey_exists(c, pick.ptr.dev);
 
 	/*
 	 * Stale dirty pointers are treated as IO errors, but @failed isn't
diff --git a/fs/bcachefs/io_write.c b/fs/bcachefs/io_write.c
index 420e5baf5054..aeb90b64875c 100644
--- a/fs/bcachefs/io_write.c
+++ b/fs/bcachefs/io_write.c
@@ -399,9 +399,9 @@ void bch2_submit_wbio_replicas(struct bch_write_bio *wbio, struct bch_fs *c,
 	BUG_ON(c->opts.nochanges);
 
 	bkey_for_each_ptr(ptrs, ptr) {
-		BUG_ON(!bch2_dev_exists2(c, ptr->dev));
+		BUG_ON(!bch2_dev_exists(c, ptr->dev));
 
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 
 		if (to_entry(ptr + 1) < ptrs.end) {
 			n = to_wbio(bio_alloc_clone(NULL, &wbio->bio,
@@ -642,7 +642,7 @@ static void bch2_write_endio(struct bio *bio)
 	struct bch_write_bio *wbio	= to_wbio(bio);
 	struct bch_write_bio *parent	= wbio->split ? wbio->parent : NULL;
 	struct bch_fs *c		= wbio->c;
-	struct bch_dev *ca		= bch_dev_bkey_exists(c, wbio->dev);
+	struct bch_dev *ca		= bch2_dev_bkey_exists(c, wbio->dev);
 
 	if (bch2_dev_inum_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_write,
 				    op->pos.inode,
@@ -1264,7 +1264,7 @@ retry:
 				bucket_nocow_lock(&c->nocow_locks, bucket_to_u64(b));
 			prefetch(l);
 
-			if (unlikely(!bch2_dev_get_ioref(bch_dev_bkey_exists(c, ptr->dev), WRITE)))
+			if (unlikely(!bch2_dev_get_ioref(bch2_dev_bkey_exists(c, ptr->dev), WRITE)))
 				goto err_get_ioref;
 
 			/* XXX allocating memory with btree locks held - rare */
@@ -1285,7 +1285,7 @@ retry:
 			bch2_cut_back(POS(op->pos.inode, op->pos.offset + bio_sectors(bio)), op->insert_keys.top);
 
 		darray_for_each(buckets, i) {
-			struct bch_dev *ca = bch_dev_bkey_exists(c, i->b.inode);
+			struct bch_dev *ca = bch2_dev_bkey_exists(c, i->b.inode);
 
 			__bch2_bucket_nocow_lock(&c->nocow_locks, i->l,
 						 bucket_to_u64(i->b),
@@ -1362,7 +1362,7 @@ err:
 	return;
 err_get_ioref:
 	darray_for_each(buckets, i)
-		percpu_ref_put(&bch_dev_bkey_exists(c, i->b.inode)->io_ref);
+		percpu_ref_put(&bch2_dev_bkey_exists(c, i->b.inode)->io_ref);
 
 	/* Fall back to COW path: */
 	goto out;
diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c
index b2ed4d38c19d..e726d9f560a0 100644
--- a/fs/bcachefs/journal_io.c
+++ b/fs/bcachefs/journal_io.c
@@ -21,7 +21,7 @@ void bch2_journal_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
 			       struct journal_replay *j)
 {
 	darray_for_each(j->ptrs, i) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, i->dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, i->dev);
 		u64 offset;
 
 		div64_u64_rem(i->sector, ca->mi.bucket_size, &offset);
@@ -677,7 +677,7 @@ static int journal_entry_dev_usage_validate(struct bch_fs *c,
 
 	dev = le32_to_cpu(u->dev);
 
-	if (journal_entry_err_on(!bch2_dev_exists2(c, dev),
+	if (journal_entry_err_on(!bch2_dev_exists(c, dev),
 				 c, version, jset, entry,
 				 journal_entry_dev_usage_bad_dev,
 				 "bad dev")) {
@@ -1390,7 +1390,7 @@ int bch2_journal_read(struct bch_fs *c,
 			continue;
 
 		darray_for_each(i->ptrs, ptr) {
-			struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+			struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 
 			if (!ptr->csum_good)
 				bch_err_dev_offset(ca, ptr->sector,
@@ -1400,7 +1400,7 @@ int bch2_journal_read(struct bch_fs *c,
 		}
 
 		ret = jset_validate(c,
-				    bch_dev_bkey_exists(c, i->ptrs.data[0].dev),
+				    bch2_dev_bkey_exists(c, i->ptrs.data[0].dev),
 				    &i->j,
 				    i->ptrs.data[0].sector,
 				    READ);
@@ -1731,7 +1731,7 @@ static CLOSURE_CALLBACK(do_journal_write)
 	unsigned sectors = vstruct_sectors(w->data, c->block_bits);
 
 	extent_for_each_ptr(bkey_i_to_s_extent(&w->key), ptr) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, ptr->dev);
 		struct journal_device *ja = &ca->journal;
 
 		if (!percpu_ref_tryget(&ca->io_ref)) {
diff --git a/fs/bcachefs/move.c b/fs/bcachefs/move.c
index 3084a2edc20b..aaacc147df77 100644
--- a/fs/bcachefs/move.c
+++ b/fs/bcachefs/move.c
@@ -711,7 +711,7 @@ int bch2_evacuate_bucket(struct moving_context *ctxt,
 
 	a = bch2_alloc_to_v4(k, &a_convert);
 	dirty_sectors = bch2_bucket_sectors_dirty(*a);
-	bucket_size = bch_dev_bkey_exists(c, bucket.inode)->mi.bucket_size;
+	bucket_size = bch2_dev_bkey_exists(c, bucket.inode)->mi.bucket_size;
 	fragmentation = a->fragmentation_lru;
 
 	ret = bch2_btree_write_buffer_tryflush(trans);
diff --git a/fs/bcachefs/recovery.c b/fs/bcachefs/recovery.c
index 73c92940ca4b..113b374abf12 100644
--- a/fs/bcachefs/recovery.c
+++ b/fs/bcachefs/recovery.c
@@ -369,7 +369,7 @@ static int journal_replay_entry_early(struct bch_fs *c,
 	case BCH_JSET_ENTRY_dev_usage: {
 		struct jset_entry_dev_usage *u =
 			container_of(entry, struct jset_entry_dev_usage, entry);
-		struct bch_dev *ca = bch_dev_bkey_exists(c, le32_to_cpu(u->dev));
+		struct bch_dev *ca = bch2_dev_bkey_exists(c, le32_to_cpu(u->dev));
 		unsigned i, nr_types = jset_entry_dev_usage_nr_types(u);
 
 		for (i = 0; i < min_t(unsigned, nr_types, BCH_DATA_NR); i++) {
diff --git a/fs/bcachefs/replicas.c b/fs/bcachefs/replicas.c
index 678b9c20e251..f2c99703c730 100644
--- a/fs/bcachefs/replicas.c
+++ b/fs/bcachefs/replicas.c
@@ -84,7 +84,7 @@ int bch2_replicas_entry_validate(struct bch_replicas_entry_v1 *r,
 	}
 
 	for (unsigned i = 0; i < r->nr_devs; i++)
-		if (!bch2_dev_exists(sb, r->devs[i])) {
+		if (!bch2_member_exists(sb, r->devs[i])) {
 			prt_printf(err, "invalid device %u in entry ", r->devs[i]);
 			goto bad;
 		}
@@ -200,7 +200,7 @@ cpu_replicas_add_entry(struct bch_fs *c,
 	};
 
 	for (i = 0; i < new_entry->nr_devs; i++)
-		BUG_ON(!bch2_dev_exists2(c, new_entry->devs[i]));
+		BUG_ON(!bch2_dev_exists(c, new_entry->devs[i]));
 
 	BUG_ON(!new_entry->data_type);
 	verify_replicas_entry(new_entry);
@@ -954,7 +954,7 @@ bool bch2_have_enough_devs(struct bch_fs *c, struct bch_devs_mask devs,
 			continue;
 
 		for (i = 0; i < e->nr_devs; i++) {
-			struct bch_dev *ca = bch_dev_bkey_exists(c, e->devs[i]);
+			struct bch_dev *ca = bch2_dev_bkey_exists(c, e->devs[i]);
 
 			nr_online += test_bit(e->devs[i], devs.d);
 			nr_failed += ca->mi.state == BCH_MEMBER_STATE_failed;
diff --git a/fs/bcachefs/sb-members.c b/fs/bcachefs/sb-members.c
index 7cf570970ba8..9b7a2f300182 100644
--- a/fs/bcachefs/sb-members.c
+++ b/fs/bcachefs/sb-members.c
@@ -163,7 +163,7 @@ static void member_to_text(struct printbuf *out,
 	u64 bucket_size = le16_to_cpu(m.bucket_size);
 	u64 device_size = le64_to_cpu(m.nbuckets) * bucket_size;
 
-	if (!bch2_member_exists(&m))
+	if (!bch2_member_alive(&m))
 		return;
 
 	prt_printf(out, "Device:\t%u\n", i);
diff --git a/fs/bcachefs/sb-members.h b/fs/bcachefs/sb-members.h
index 868f2b0b505a..bc3bcfef7b3a 100644
--- a/fs/bcachefs/sb-members.h
+++ b/fs/bcachefs/sb-members.h
@@ -157,26 +157,38 @@ static inline struct bch_dev *bch2_get_next_online_dev(struct bch_fs *c,
 #define for_each_readable_member(c, ca)				\
 	__for_each_online_member(c, ca,	BIT( BCH_MEMBER_STATE_rw)|BIT(BCH_MEMBER_STATE_ro))
 
+static inline bool bch2_dev_exists(const struct bch_fs *c, unsigned dev)
+{
+	return dev < c->sb.nr_devices && c->devs[dev];
+}
+
 /*
  * If a key exists that references a device, the device won't be going away and
  * we can omit rcu_read_lock():
  */
-static inline struct bch_dev *bch_dev_bkey_exists(const struct bch_fs *c, unsigned idx)
+static inline struct bch_dev *bch2_dev_bkey_exists(const struct bch_fs *c, unsigned dev)
 {
-	EBUG_ON(idx >= c->sb.nr_devices || !c->devs[idx]);
+	EBUG_ON(!bch2_dev_exists(c, dev));
 
-	return rcu_dereference_check(c->devs[idx], 1);
+	return rcu_dereference_check(c->devs[dev], 1);
 }
 
-static inline struct bch_dev *bch_dev_locked(struct bch_fs *c, unsigned idx)
+static inline struct bch_dev *bch2_dev_locked(struct bch_fs *c, unsigned dev)
 {
-	EBUG_ON(idx >= c->sb.nr_devices || !c->devs[idx]);
+	EBUG_ON(!bch2_dev_exists(c, dev));
 
-	return rcu_dereference_protected(c->devs[idx],
+	return rcu_dereference_protected(c->devs[dev],
 					 lockdep_is_held(&c->sb_lock) ||
 					 lockdep_is_held(&c->state_lock));
 }
 
+static inline struct bch_dev *bch2_dev_safe(struct bch_fs *c, unsigned dev)
+{
+	return c && dev < c->sb.nr_devices
+		? rcu_dereference(c->devs[dev])
+		: NULL;
+}
+
 /* XXX kill, move to struct bch_fs */
 static inline struct bch_devs_mask bch2_online_devs(struct bch_fs *c)
 {
@@ -191,16 +203,16 @@ static inline struct bch_devs_mask bch2_online_devs(struct bch_fs *c)
 extern const struct bch_sb_field_ops bch_sb_field_ops_members_v1;
 extern const struct bch_sb_field_ops bch_sb_field_ops_members_v2;
 
-static inline bool bch2_member_exists(struct bch_member *m)
+static inline bool bch2_member_alive(struct bch_member *m)
 {
 	return !bch2_is_zero(&m->uuid, sizeof(m->uuid));
 }
 
-static inline bool bch2_dev_exists(struct bch_sb *sb, unsigned dev)
+static inline bool bch2_member_exists(struct bch_sb *sb, unsigned dev)
 {
 	if (dev < sb->nr_devices) {
 		struct bch_member m = bch2_sb_member_get(sb, dev);
-		return bch2_member_exists(&m);
+		return bch2_member_alive(&m);
 	}
 	return false;
 }
@@ -221,7 +233,7 @@ static inline struct bch_member_cpu bch2_mi_to_cpu(struct bch_member *mi)
 			? BCH_MEMBER_DURABILITY(mi) - 1
 			: 1,
 		.freespace_initialized = BCH_MEMBER_FREESPACE_INITIALIZED(mi),
-		.valid		= bch2_member_exists(mi),
+		.valid		= bch2_member_alive(mi),
 	};
 }
 
diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c
index fc78af675815..437626eb8ac7 100644
--- a/fs/bcachefs/super-io.c
+++ b/fs/bcachefs/super-io.c
@@ -1271,7 +1271,7 @@ void bch2_sb_to_text(struct printbuf *out, struct bch_sb *sb,
 		printbuf_tabstop_push(out, 44);
 
 	for (int i = 0; i < sb->nr_devices; i++)
-		nr_devices += bch2_dev_exists(sb, i);
+		nr_devices += bch2_member_exists(sb, i);
 
 	prt_printf(out, "External UUID:\t");
 	pr_uuid(out, sb->user_uuid.b);
diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index c7a007673d1a..f26dcc7e9a55 100644
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -940,7 +940,7 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
 		goto err;
 
 	for (i = 0; i < c->sb.nr_devices; i++)
-		if (bch2_dev_exists(c->disk_sb.sb, i) &&
+		if (bch2_member_exists(c->disk_sb.sb, i) &&
 		    bch2_dev_alloc(c, i)) {
 			ret = -EEXIST;
 			goto err;
@@ -1101,7 +1101,7 @@ static int bch2_dev_in_fs(struct bch_sb_handle *fs,
 	if (!uuid_equal(&fs->sb->uuid, &sb->sb->uuid))
 		return -BCH_ERR_device_not_a_member_of_filesystem;
 
-	if (!bch2_dev_exists(fs->sb, sb->sb->dev_idx))
+	if (!bch2_member_exists(fs->sb, sb->sb->dev_idx))
 		return -BCH_ERR_device_has_been_removed;
 
 	if (fs->sb->block_size != sb->sb->block_size)
@@ -1411,10 +1411,9 @@ static int bch2_dev_attach_bdev(struct bch_fs *c, struct bch_sb_handle *sb)
 	    le64_to_cpu(c->disk_sb.sb->seq))
 		bch2_sb_to_fs(c, sb->sb);
 
-	BUG_ON(sb->sb->dev_idx >= c->sb.nr_devices ||
-	       !c->devs[sb->sb->dev_idx]);
+	BUG_ON(!bch2_dev_exists(c, sb->sb->dev_idx));
 
-	ca = bch_dev_locked(c, sb->sb->dev_idx);
+	ca = bch2_dev_locked(c, sb->sb->dev_idx);
 
 	ret = __bch2_dev_attach_bdev(ca, sb);
 	if (ret)
@@ -1506,10 +1505,10 @@ static bool bch2_fs_may_start(struct bch_fs *c)
 		mutex_lock(&c->sb_lock);
 
 		for (i = 0; i < c->disk_sb.sb->nr_devices; i++) {
-			if (!bch2_dev_exists(c->disk_sb.sb, i))
+			if (!bch2_member_exists(c->disk_sb.sb, i))
 				continue;
 
-			ca = bch_dev_locked(c, i);
+			ca = bch2_dev_locked(c, i);
 
 			if (!bch2_dev_is_online(ca) &&
 			    (ca->mi.state == BCH_MEMBER_STATE_rw ||
@@ -1778,7 +1777,7 @@ int bch2_dev_add(struct bch_fs *c, const char *path)
 		goto no_slot;
 
 	for (dev_idx = 0; dev_idx < BCH_SB_MEMBERS_MAX; dev_idx++)
-		if (!bch2_dev_exists(c->disk_sb.sb, dev_idx))
+		if (!bch2_member_exists(c->disk_sb.sb, dev_idx))
 			goto have_slot;
 no_slot:
 	ret = -BCH_ERR_ENOSPC_sb_members;
@@ -1884,7 +1883,7 @@ int bch2_dev_online(struct bch_fs *c, const char *path)
 	if (ret)
 		goto err;
 
-	ca = bch_dev_locked(c, dev_idx);
+	ca = bch2_dev_locked(c, dev_idx);
 
 	ret = bch2_trans_mark_dev_sb(c, ca, BTREE_TRIGGER_transactional);
 	bch_err_msg(c, ret, "bringing %s online: error from bch2_trans_mark_dev_sb", path);