Re: [PATCH 4/4] xfstests: Add support for btrfs in 079

[Christoph Hellwig <hch@infradead.org>]

On Thu, Jul 28, 2011 at 10:28:01AM +0200, Stefan Behrens wrote:
> Added btrfs to the list of supported filesystems for test 079.
> In src/t_immutable.c which is compiled for Linux only, add support for
> btrfs by replacing the ioctl(EXT2_IOC_SETFLAGS) with
> ioctl(FS_IOC_SETFLAGS) which is defined to be the same.

That has nothing to do with btrfs support.  Your patch means we recent
kernel headers to get the FS_IOC_SETFLAGS instead of having a local one.
I don't care what name to use for the local one, and I also don't
mind an ifdef to pick up a header one in preference, but as-is the patch
isn't too useful as FS_IOC_SETFLAGS is a fairly recent addition to the
kernel headers, and we will break existing working setups.

> Afterwards in src/t_immutable.c in function fsetflag(), share the code
> branch for the ext2 case also for the btrfs case.
> Furthermore, added missing call to ioctl(FS_IOC_GETFLAGS) to the ext3
> and btrfs code branch, this was a difference to the way the XFS code
> branch was implemented.

I'd suggest to completely drop the stat check, and use the ext2 branch
unconditionally.  The ioctl is suppored by all major filesystems.

This also means we can make the test generic, maybe with a _notrun
instead of an error if FS_IOC_GETFLAGS/FS_IOC_SETFLAGS isn't supported.