On Tue, Apr 14, 2020 at 11:45:18PM -0700, ira.weiny@xxxxxxxxx wrote:
> From: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> xfs_inode_supports_dax() should reflect if the inode can support DAX not
> that it is enabled for DAX.
>
> Change the use of xfs_inode_supports_dax() to reflect only if the inode
> and underlying storage support dax.
>
> Add a new function xfs_inode_enable_dax() which reflects if the inode
> should be enabled for DAX.
>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> ---
> Changes from v7:
> Move S_ISREG check first
> use IS_ENABLED(CONFIG_FS_DAX) rather than duplicated function
>
> Changes from v6:
> Change enable checks to be sequential logic.
> Update for 2 bit tri-state option.
> Make 'static' consistent.
> Don't set S_DAX if !CONFIG_FS_DAX
>
> Changes from v5:
> Update to reflect the new tri-state mount option
>
> Changes from v3:
> Update functions and names to be more clear
> Update commit message
> Merge with
> 'fs/xfs: Clean up DAX support check'
> don't allow IS_DAX() on a directory
> use STATIC macro for static
> make xfs_inode_supports_dax() static
> ---
> fs/xfs/xfs_iops.c | 28 ++++++++++++++++++++++------
> 1 file changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index a6e634631da8..2ecc2b2050ab 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -1243,13 +1243,12 @@ xfs_inode_supports_dax(
> {
> struct xfs_mount *mp = ip->i_mount;
>
> - /* Only supported on non-reflinked files. */
> - if (!S_ISREG(VFS_I(ip)->i_mode) || xfs_is_reflink_inode(ip))
> + /* Only supported on regular files. */
> + if (!S_ISREG(VFS_I(ip)->i_mode))
> return false;
>
> - /* DAX mount option or DAX iflag must be set. */
> - if (!(mp->m_flags & XFS_MOUNT_DAX_ALWAYS) &&
> - !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
> + /* Only supported on non-reflinked files. */
> + if (xfs_is_reflink_inode(ip))
> return false;
>
> /* Block size must match page size */
> @@ -1260,6 +1259,23 @@ xfs_inode_supports_dax(
> return xfs_inode_buftarg(ip)->bt_daxdev != NULL;
> }
>
> +static bool
> +xfs_inode_enable_dax(
> + struct xfs_inode *ip)
> +{
> + if (!IS_ENABLED(CONFIG_FS_DAX))
> + return false;
> + if (ip->i_mount->m_flags & XFS_MOUNT_DAX_NEVER)
> + return false;
> + if (!xfs_inode_supports_dax(ip))
> + return false;
> + if (ip->i_mount->m_flags & XFS_MOUNT_DAX_ALWAYS)
> + return true;
> + if (ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
> + return true;
> + return false;
You could simplify the last two lines by making them read:
return ip->i_d.di_flags2 & XFS_DIFLAG2_DAX;
But it's probably not worth respinning the whole thing just for that.
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
--D
> +}
> +
> STATIC void
> xfs_diflags_to_iflags(
> struct inode *inode,
> @@ -1278,7 +1294,7 @@ xfs_diflags_to_iflags(
> inode->i_flags |= S_SYNC;
> if (flags & XFS_DIFLAG_NOATIME)
> inode->i_flags |= S_NOATIME;
> - if (xfs_inode_supports_dax(ip))
> + if (xfs_inode_enable_dax(ip))
> inode->i_flags |= S_DAX;
> }
>
> --
> 2.25.1
>
