Re: [PATCH] common/defrag: Skip defrag tests on DAX-enabled filesystems

["Darrick J. Wong" <djwong@kernel.org>]

On Tue, Jun 02, 2026 at 03:44:18PM +0530, Disha Goel wrote:
> Online defragmentation is not supported on DAX-enabled filesystems
> because DAX bypasses the page cache required for defrag operations.
> 
> Add check in _require_defrag() to skip tests when DAX is enabled,
> avoiding false failures on ext4/301-304, ext4/308 and generic/018.
> 
> Signed-off-by: Disha Goel <disgoel@linux.ibm.com>
> ---
>  common/defrag | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/common/defrag b/common/defrag
> index 055d0d0e..28db2f7a 100644
> --- a/common/defrag
> +++ b/common/defrag
> @@ -6,6 +6,10 @@
>  
>  _require_defrag()
>  {
> +    # Defragmentation is not supported on DAX-enabled filesystems
> +    if echo "$MOUNT_OPTIONS" | grep -qw "dax"; then
> +        _notrun "Defragmentation not supported on DAX-enabled filesystem"
> +    fi

Defrag doesn't work on XFS on DAX as well?  It seems to work fine on my
VMs...

<confused>

--D

>      case "$FSTYP" in
>      xfs)
>          # xfs_fsr does preallocates, require "falloc"
> -- 
> 2.45.1
> 
>