Re: [PATCH v3 1/3] common/atomicwrites: add helper for multi block atomic writes

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

Catherine Hoang <catherine.hoang@oracle.com> writes:

> Add a helper to check that we can perform multi block atomic writes.
>
> Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
> ---
>  common/atomicwrites | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
>
> diff --git a/common/atomicwrites b/common/atomicwrites
> index 391bb6f6..88f49a1a 100644
> --- a/common/atomicwrites
> +++ b/common/atomicwrites
> @@ -24,6 +24,27 @@ _get_atomic_write_segments_max()
>          grep -w atomic_write_segments_max | grep -o '[0-9]\+'
>  }
>  
> +_require_scratch_write_atomic_multi_fsblock()
> +{
> +    _require_scratch
> +
> +    _scratch_mkfs > /dev/null 2>&1 || \
> +        _notrun "cannot format scratch device for atomic write checks"
> +    _try_scratch_mount || \
> +        _notrun "cannot mount scratch device for atomic write checks"
> +
> +    local testfile=$SCRATCH_MNT/testfile
> +    touch $testfile
> +
> +    local bsize=$(_get_file_block_size $SCRATCH_MNT)
> +    local awu_max_fs=$(_get_atomic_write_unit_max $testfile)
> +
> +    _scratch_unmount
> +
> +    test $awu_max_fs -ge $((bsize * 2)) || \
> +        _notrun "multi-block atomic writes not supported by this filesystem"
> +}
> +

Looks good. Please feel free to add:
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>

-ritesh