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 <[email protected]>
The idea is pretty good, will help later readers.
Reviewed-by: Qu Wenruo <[email protected]>
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,
>
