Re: [PATCH 1/2] dax: pass bdev argument to dax_clear_blocks()

[Dan Williams <dan.j.williams@xxxxxxxxx>]

On Sat, Feb 6, 2016 at 11:19 PM, Ross Zwisler
<ross.zwisler@xxxxxxxxxxxxxxx> wrote:
> dax_clear_blocks() needs a valid struct block_device and previously it was
> using inode->i_sb->s_bdev in all cases.  This is correct for normal inodes
> on mounted ext2, ext4 and XFS filesystems, but is incorrect for DAX raw
> block devices and for XFS real-time devices.
>
> Instead, have the caller pass in a struct block_device pointer which it
> knows to be correct.
>
> Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
> ---
>  fs/dax.c               | 4 ++--
>  fs/ext2/inode.c        | 5 +++--
>  fs/xfs/xfs_aops.c      | 2 +-
>  fs/xfs/xfs_aops.h      | 1 +
>  fs/xfs/xfs_bmap_util.c | 4 +++-
>  include/linux/dax.h    | 3 ++-
>  6 files changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index 227974a..4592241 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -83,9 +83,9 @@ struct page *read_dax_sector(struct block_device *bdev, 
> sector_t n)
>   * and hence this means the stack from this point must follow GFP_NOFS
>   * semantics for all operations.
>   */
> -int dax_clear_blocks(struct inode *inode, sector_t block, long _size)
> +int dax_clear_blocks(struct inode *inode, struct block_device *bdev,
> +               sector_t block, long _size)

Since this is a bdev relative routine we should also resolve the
sector, i.e. the signature should drop the inode:

int dax_clear_sectors(struct block_device *bdev, sector_t sector, long _size)