Re: [PATCH v4 01/34] ext4: factor out a common helper to query extent map

[Ritesh Harjani (IBM) <ritesh.list@gmail.com>]

Zhang Yi <yi.zhang@huaweicloud.com> writes:

> From: Zhang Yi <yi.zhang@huawei.com>
>
> Factor out a new common helper ext4_map_query_blocks() from the
> ext4_da_map_blocks(), it query and return the extent map status on the
> inode's extent path, no logic changes.
>
> Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
> ---
>  fs/ext4/inode.c | 57 +++++++++++++++++++++++++++----------------------
>  1 file changed, 32 insertions(+), 25 deletions(-)

Looks good to me. Straight forward refactoring.
Feel free to add - 

Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>

>
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 537803250ca9..6a41172c06e1 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -453,6 +453,35 @@ static void ext4_map_blocks_es_recheck(handle_t *handle,
>  }
>  #endif /* ES_AGGRESSIVE_TEST */
>  
> +static int ext4_map_query_blocks(handle_t *handle, struct inode *inode,
> +				 struct ext4_map_blocks *map)
> +{
> +	unsigned int status;
> +	int retval;
> +
> +	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
> +		retval = ext4_ext_map_blocks(handle, inode, map, 0);
> +	else
> +		retval = ext4_ind_map_blocks(handle, inode, map, 0);
> +
> +	if (retval <= 0)
> +		return retval;
> +
> +	if (unlikely(retval != map->m_len)) {
> +		ext4_warning(inode->i_sb,
> +			     "ES len assertion failed for inode "
> +			     "%lu: retval %d != map->m_len %d",
> +			     inode->i_ino, retval, map->m_len);
> +		WARN_ON(1);
> +	}
> +
> +	status = map->m_flags & EXT4_MAP_UNWRITTEN ?
> +			EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
> +	ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
> +			      map->m_pblk, status);
> +	return retval;
> +}
> +
>  /*
>   * The ext4_map_blocks() function tries to look up the requested blocks,
>   * and returns if the blocks are already mapped.
> @@ -1744,33 +1773,11 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
>  	down_read(&EXT4_I(inode)->i_data_sem);
>  	if (ext4_has_inline_data(inode))
>  		retval = 0;
> -	else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
> -		retval = ext4_ext_map_blocks(NULL, inode, map, 0);
>  	else
> -		retval = ext4_ind_map_blocks(NULL, inode, map, 0);
> -	if (retval < 0) {
> -		up_read(&EXT4_I(inode)->i_data_sem);
> -		return retval;
> -	}
> -	if (retval > 0) {
> -		unsigned int status;
> -
> -		if (unlikely(retval != map->m_len)) {
> -			ext4_warning(inode->i_sb,
> -				     "ES len assertion failed for inode "
> -				     "%lu: retval %d != map->m_len %d",
> -				     inode->i_ino, retval, map->m_len);
> -			WARN_ON(1);
> -		}
> -
> -		status = map->m_flags & EXT4_MAP_UNWRITTEN ?
> -				EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
> -		ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
> -				      map->m_pblk, status);
> -		up_read(&EXT4_I(inode)->i_data_sem);
> -		return retval;
> -	}
> +		retval = ext4_map_query_blocks(NULL, inode, map);
>  	up_read(&EXT4_I(inode)->i_data_sem);
> +	if (retval)
> +		return retval;
>  
>  add_delayed:
>  	down_write(&EXT4_I(inode)->i_data_sem);
> -- 
> 2.39.2