Re: [PATCH 1/4] btrfs: Document __etree_search

[Johannes Thumshirn <jthumshirn@suse.de>]

On Mon, Jun 03, 2019 at 01:05:59PM +0300, 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@suse.com>
> ---
>  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.
> + *

This is missing @tree, make W=1 should warn about this.

> + * @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.
> + */
>  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
> 

-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
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