On 2019/6/3 下午6:05, Nikolay Borisov wrote: > 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> The idea is pretty good, will help later readers. Reviewed-by: Qu Wenruo <wqu@xxxxxxxx> Just a small nitpick inlined below. > --- > fs/btrfs/extent_io.c | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > index e56afb826517..d5979558c96f 100644 > --- a/fs/btrfs/extent_io.c > +++ b/fs/btrfs/extent_io.c > @@ -359,6 +359,22 @@ 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. > + * > + * @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. it would be better to mention when found, the remaining pointers are untouched. > If no such entry exists, then NULL is returned and the other > + * pointer arguments to the function are filled. > + */ > static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, > struct rb_node **next_ret, > struct rb_node **prev_ret, >
