The function has a lot of return values and specific conventions making it cumbersome to understand what's returned. Have a go at documenting its parameters and return values. Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx> --- * Document 'tree' argument to silence error (Johaness) * Document that if a range is found then none of the input pointers is touched (Qu) fs/btrfs/extent_io.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index e56afb826517..d7913f42327c 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -359,6 +359,24 @@ static struct rb_node *tree_insert(struct rb_root *root, return NULL; } +/** + * __etree_search - searches @tree for an entry that contains @offset. Such + * entry would have entry->start <= offset && entry->end >= offset. + * + * @tree - the tree to search + * @offset - offset that should fall within an entry in @tree + * @next_ret - pointer to the first entry whose range ends after @offset + * @prev - pointer to the first entry whose range begins before @offset + * @p_ret - pointer where new node should be anchored (used when inserting an + * entry in the tree) + * @parent_ret - points to entry which would have been the parent of the entry, + * containing @offset + * + * This function returns a pointer to the entry that contains @offset byte + * address. If no such entry exists, then NULL is returned and the other + * pointer arguments to the function are filled, otherwise the found entry is + * return and other pointers are left untouched. + */ static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, struct rb_node **next_ret, struct rb_node **prev_ret, -- 2.17.1
