btrfs: remove pointless loop at btrfs_get_next_valid_item()

It's pointless to have a while loop at btrfs_get_next_valid_item(), as if
the slot on the current leaf is beyond the last item, we call
btrfs_next_leaf(), which leaves us at a valid slot of the next leaf (or
a valid slot in the current leaf if after releasing the path an item gets
pushed from the next leaf to the current leaf).

So just call btrfs_next_leaf() if the current slot on the current leaf is
beyond the last item.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/ctree.c

@@ -2490,26 +2490,15 @@ int btrfs_search_backwards(struct btrfs_root *root, struct btrfs_key *key,
 int btrfs_get_next_valid_item(struct btrfs_root *root, struct btrfs_key *key,
 			      struct btrfs_path *path)
 {
-	while (1) {
+	if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
 		int ret;
-		const int slot = path->slots[0];
-		const struct extent_buffer *leaf = path->nodes[0];
 
-		/* This is where we start walking the path. */
-		if (slot >= btrfs_header_nritems(leaf)) {
-			/*
-			 * If we've reached the last slot in this leaf we need
-			 * to go to the next leaf and reset the path.
-			 */
-			ret = btrfs_next_leaf(root, path);
-			if (ret)
-				return ret;
-			continue;
-		}
-		/* Store the found, valid item in @key. */
-		btrfs_item_key_to_cpu(leaf, key, slot);
-		break;
+		ret = btrfs_next_leaf(root, path);
+		if (ret)
+			return ret;
 	}
+
+	btrfs_item_key_to_cpu(path->nodes[0], key, path->slots[0]);
 	return 0;
 }