If the size of an inline directory is so small that it doesn't
even cover the required header size, return an error to userspace
instead of ASSERTing and returning 0 like everything's ok.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reported-by: NJan Kara <jack@suse.cz>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>