Re: [PATCH] generic/556: add a check to make sure ext4 supports encrypted casefolding

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

On Mon, Jun 21, 2021 at 12:49:01PM -0400, Theodore Ts'o wrote:
> Some older kernels support ext4 file systems with encryption enabled,
> and with casefold enabled, but not file systems have both encryption
> *and* casefolding enabled.  On those kernels, generic/556 will fail.
> Fortunately, we can test if ext4 supports encrypted casefold via the
> presence of /sys/fs/ext4/features/encrypted_casefold.
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> ---
>  common/casefold   | 17 +++++++++++++++++
>  tests/generic/556 |  1 +
>  2 files changed, 18 insertions(+)
> 
> diff --git a/common/casefold b/common/casefold
> index 9172d818..7b76b986 100644
> --- a/common/casefold
> +++ b/common/casefold
> @@ -43,6 +43,23 @@ _require_scratch_casefold()
>  	_require_command "$LSATTR_PROG" lsattr
>  }
>  
> +_require_encrypted_casefold ()
> +{
> +    case $FSTYP in
> +	ext4)
> +	    if test ! -f /sys/fs/ext4/features/casefold ; then
> +		_notrun "casefolding not supported"
> +	    fi
> +	    if test ! -f /sys/fs/ext4/features/encryption ; then
> +		_notrun "file system encryption not supported"
> +	    fi
> +	    if test ! -f /sys/fs/ext4/features/encrypted_casefold ; then
> +		_notrun "encrypted casefolding not supported"

Dumb question: Are there kernels that support encrypted casefold but not
those two components separately?

--D

> +	    fi
> +	    ;;
> +	esac
> +}
> +
>  _scratch_mkfs_casefold()
>  {
>  	case $FSTYP in
> diff --git a/tests/generic/556 b/tests/generic/556
> index 3145188c..7916a08e 100755
> --- a/tests/generic/556
> +++ b/tests/generic/556
> @@ -16,6 +16,7 @@ status=1 # failure is thea default
>  . ./common/attr
>  
>  _supported_fs generic
> +_require_encrypted_casefold
>  _require_scratch_nocheck
>  _require_scratch_casefold
>  _require_symlinks
> -- 
> 2.31.0
>