Re: [PATCH 1/2] btrfs: Introduce btrfs_io_geometry

[David Sterba <dsterba@suse.cz>]

On Fri, May 31, 2019 at 06:01:14PM +0300, Nikolay Borisov wrote:
> ---
>  fs/btrfs/volumes.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++
>  fs/btrfs/volumes.h |  2 +
>  2 files changed, 100 insertions(+)
> 
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 776f5c7ca7c5..b130f465ca6d 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -5907,6 +5907,104 @@ static bool need_full_stripe(enum btrfs_map_op op)
>  	return (op == BTRFS_MAP_WRITE || op == BTRFS_MAP_GET_READ_MIRRORS);
>  }
>  
> +/*
> + * btrfs_io_geometry - calculates the geomery of a particular (address, len)
> + *		       tuple. This information is used to calculate how big a
> + *		       particular bio can get before it straddles a stripe.
> + *
> + * @fs_info - The omnipresent btrfs structure
> + * @logical - Address that we want to figure out the geometry of
> + * @len	    - The length of IO we are going to perform, starting at @logical
> + * @op      - Type of operation - Write or Read
> + * @io_geom - Pointer used to return values
> + *
> + * Returns < 0 in case a chunk for the given logical address cannot be found,
> + * usually shouldn't happen unless @logical is corrupted, 0 otherwise.
> + */
> +int btrfs_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
> +		      u64 logical, u64 len, struct btrfs_io_geometry *io_geom)

Where is struct btrfs_io_geometry defined?

And changelog and signed-off-by are missing.