diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index ac6c383d63140bc395f4e6beef7037d803036259..19855659f65030d57d1e56fb5f93341ab4efe477 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1485,7 +1485,7 @@ int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr)
 		goto out;
 	}
 
-	trans = btrfs_attach_transaction(root);
+	trans = btrfs_join_transaction_nostart(root);
 	if (IS_ERR(trans)) {
 		if (PTR_ERR(trans) != -ENOENT && PTR_ERR(trans) != -EROFS) {
 			ret = PTR_ERR(trans);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index f1ca53a3ff0bf05ad2cd453fdd1ebdaffb46888d..26317bca56499a406492dd84e4a602e2ee00f1eb 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -28,15 +28,18 @@ static const unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = {
 	[TRANS_STATE_COMMIT_START]	= (__TRANS_START | __TRANS_ATTACH),
 	[TRANS_STATE_COMMIT_DOING]	= (__TRANS_START |
 					   __TRANS_ATTACH |
-					   __TRANS_JOIN),
+					   __TRANS_JOIN |
+					   __TRANS_JOIN_NOSTART),
 	[TRANS_STATE_UNBLOCKED]		= (__TRANS_START |
 					   __TRANS_ATTACH |
 					   __TRANS_JOIN |
-					   __TRANS_JOIN_NOLOCK),
+					   __TRANS_JOIN_NOLOCK |
+					   __TRANS_JOIN_NOSTART),
 	[TRANS_STATE_COMPLETED]		= (__TRANS_START |
 					   __TRANS_ATTACH |
 					   __TRANS_JOIN |
-					   __TRANS_JOIN_NOLOCK),
+					   __TRANS_JOIN_NOLOCK |
+					   __TRANS_JOIN_NOSTART),
 };
 
 void btrfs_put_transaction(struct btrfs_transaction *transaction)
@@ -531,7 +534,8 @@ start_transaction(struct btrfs_root *root, unsigned int num_items,
 		ret = join_transaction(fs_info, type);
 		if (ret == -EBUSY) {
 			wait_current_trans(fs_info);
-			if (unlikely(type == TRANS_ATTACH))
+			if (unlikely(type == TRANS_ATTACH ||
+				     type == TRANS_JOIN_NOSTART))
 				ret = -ENOENT;
 		}
 	} while (ret == -EBUSY);
@@ -647,6 +651,16 @@ struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root
 				 BTRFS_RESERVE_NO_FLUSH, true);
 }
 
+/*
+ * Similar to regular join but it never starts a transaction when none is
+ * running or after waiting for the current one to finish.
+ */
+struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root)
+{
+	return start_transaction(root, 0, TRANS_JOIN_NOSTART,
+				 BTRFS_RESERVE_NO_FLUSH, true);
+}
+
 /*
  * btrfs_attach_transaction() - catch the running transaction
  *
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 4cbb1b55387dc801894624f939804e253e17f414..c1d34cc70472223a81ca22de9bde27ccfc9276d5 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -97,11 +97,13 @@ struct btrfs_transaction {
 #define __TRANS_JOIN		(1U << 11)
 #define __TRANS_JOIN_NOLOCK	(1U << 12)
 #define __TRANS_DUMMY		(1U << 13)
+#define __TRANS_JOIN_NOSTART	(1U << 14)
 
 #define TRANS_START		(__TRANS_START | __TRANS_FREEZABLE)
 #define TRANS_ATTACH		(__TRANS_ATTACH)
 #define TRANS_JOIN		(__TRANS_JOIN | __TRANS_FREEZABLE)
 #define TRANS_JOIN_NOLOCK	(__TRANS_JOIN_NOLOCK)
+#define TRANS_JOIN_NOSTART	(__TRANS_JOIN_NOSTART)
 
 #define TRANS_EXTWRITERS	(__TRANS_START | __TRANS_ATTACH)
 
@@ -187,6 +189,7 @@ struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
 					int min_factor);
 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);
+struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
 					struct btrfs_root *root);