Re: [Qemu-devel] [PATCH v4 3/6] qemu-iotests: Add _default_cache_mode and _supported_cache_modes

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

This patch override only when default is specified, I am +1 with it.
I think we had discuss before, just want a double check, stefan, do you
agree with this?

> This replaces _unsupported_qemu_io_options and check for support of
> current cache mode, and allow to provide a default if user didn't
> specify.
> 
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
>   tests/qemu-iotests/026       |  3 ++-
>   tests/qemu-iotests/039       |  3 ++-
>   tests/qemu-iotests/052       |  4 ++--
>   tests/qemu-iotests/common.rc | 25 +++++++++++++++----------
>   4 files changed, 21 insertions(+), 14 deletions(-)
> 
> diff --git a/tests/qemu-iotests/026 b/tests/qemu-iotests/026
> index ebe29d0..c9c5f83 100755
> --- a/tests/qemu-iotests/026
> +++ b/tests/qemu-iotests/026
> @@ -44,7 +44,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
>   _supported_fmt qcow2
>   _supported_proto generic
>   _supported_os Linux
> -
> +_default_cache_mode "writethrough"
> +_supported_cache_modes "writethrough" "none"
> 

  Why forbid mode = writeback?

>   echo "Errors while writing 128 kB"
>   echo
> diff --git a/tests/qemu-iotests/039 b/tests/qemu-iotests/039
> index 8bade92..6abf472 100755
> --- a/tests/qemu-iotests/039
> +++ b/tests/qemu-iotests/039
> @@ -44,7 +44,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
>   _supported_fmt qcow2
>   _supported_proto generic
>   _supported_os Linux
> -_unsupported_qemu_io_options --nocache
> +_default_cache_mode "writethrough"
> +_supported_cache_modes "writethrough"
> 

  same here.

>   size=128M
> 
> diff --git a/tests/qemu-iotests/052 b/tests/qemu-iotests/052
> index f5f9683..4d4e411 100755
> --- a/tests/qemu-iotests/052
> +++ b/tests/qemu-iotests/052
> @@ -41,8 +41,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
>   _supported_fmt generic
>   _supported_proto generic
>   _supported_os Linux
> -_unsupported_qemu_io_options --nocache
> -
> +_default_cache_mode "writethrough"
> +_supported_cache_modes "writethrough"
> 

  same question.

>   size=128M
>   _make_test_img $size
> diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
> index 7f62457..47cef6d 100644
> --- a/tests/qemu-iotests/common.rc
> +++ b/tests/qemu-iotests/common.rc
> @@ -387,18 +387,23 @@ _supported_os()
>       _notrun "not suitable for this OS: $HOSTOS"
>   }
> 
> -_unsupported_qemu_io_options()
> +_supported_cache_modes()
>   {
> -    for bad_opt
> -    do
> -        for opt in $QEMU_IO_OPTIONS
> -        do
> -            if [ "$bad_opt" = "$opt" ]
> -            then
> -                _notrun "not suitable for qemu-io option: $bad_opt"
> -            fi
> -        done
> +    for mode; do
> +        if [ "$mode" = "$CACHEMODE" ]; then
> +            return
> +        fi
>       done
> +    _notrun "not suitable for cache mode: $CACHEMODE"
> +}
> +
> +_default_cache_mode()
> +{
> +    if $CACHEMODE_IS_DEFAULT; then
> +        CACHEMODE="$1"
> +        QEMU_IO="$QEMU_IO --cache $1"
> +        return
> +    fi
>   }
> 
>   # this test requires that a specified command (executable) exists
>