diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c6ecfd05e1db9649779fecf14c10d8570c565716..f4c54b7b78685e1dde21b426e710cd2b02deca48 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -106,10 +106,7 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
 	struct btrfs_delayed_ref_head *head;
 	struct btrfs_delayed_ref_root *delayed_refs;
 	struct btrfs_path *path;
-	struct btrfs_extent_item *ei;
-	struct extent_buffer *leaf;
 	struct btrfs_key key;
-	u32 item_size;
 	u64 num_refs;
 	u64 extent_flags;
 	int ret;
@@ -145,7 +142,7 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
 	if (ret < 0)
 		goto out_free;
 
-	if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) {
+	if (ret > 0 && key.type == BTRFS_METADATA_ITEM_KEY) {
 		if (path->slots[0]) {
 			path->slots[0]--;
 			btrfs_item_key_to_cpu(path->nodes[0], &key,
@@ -158,14 +155,11 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
 	}
 
 	if (ret == 0) {
-		leaf = path->nodes[0];
-		item_size = btrfs_item_size(leaf, path->slots[0]);
-		if (item_size >= sizeof(*ei)) {
-			ei = btrfs_item_ptr(leaf, path->slots[0],
-					    struct btrfs_extent_item);
-			num_refs = btrfs_extent_refs(leaf, ei);
-			extent_flags = btrfs_extent_flags(leaf, ei);
-		} else {
+		struct extent_buffer *leaf = path->nodes[0];
+		struct btrfs_extent_item *ei;
+		const u32 item_size = btrfs_item_size(leaf, path->slots[0]);
+
+		if (unlikely(item_size < sizeof(*ei))) {
 			ret = -EUCLEAN;
 			btrfs_err(fs_info,
 			"unexpected extent item size, has %u expect >= %zu",
@@ -178,7 +172,17 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
 			goto out_free;
 		}
 
-		BUG_ON(num_refs == 0);
+		ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
+		num_refs = btrfs_extent_refs(leaf, ei);
+		if (unlikely(num_refs == 0)) {
+			ret = -EUCLEAN;
+			btrfs_err(fs_info,
+		"unexpected zero reference count for extent item (%llu %u %llu)",
+				  key.objectid, key.type, key.offset);
+			btrfs_abort_transaction(trans, ret);
+			goto out_free;
+		}
+		extent_flags = btrfs_extent_flags(leaf, ei);
 	} else {
 		num_refs = 0;
 		extent_flags = 0;
@@ -208,10 +212,19 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
 			goto search_again;
 		}
 		spin_lock(&head->lock);
-		if (head->extent_op && head->extent_op->update_flags)
+		if (head->extent_op && head->extent_op->update_flags) {
 			extent_flags |= head->extent_op->flags_to_set;
-		else
-			BUG_ON(num_refs == 0);
+		} else if (unlikely(num_refs == 0)) {
+			spin_unlock(&head->lock);
+			mutex_unlock(&head->mutex);
+			spin_unlock(&delayed_refs->lock);
+			ret = -EUCLEAN;
+			btrfs_err(fs_info,
+			  "unexpected zero reference count for extent %llu (%s)",
+				  bytenr, metadata ? "metadata" : "data");
+			btrfs_abort_transaction(trans, ret);
+			goto out_free;
+		}
 
 		num_refs += head->ref_mod;
 		spin_unlock(&head->lock);