fs: FS_IOC_GETUUID

Add a new generic ioctls for querying the filesystem UUID.

These are lifted versions of the ext4 ioctls, with one change: we're not
using a flexible array member, because UUIDs will never be more than 16
bytes.

This patch adds a generic implementation of FS_IOC_GETFSUUID, which
reads from super_block->s_uuid. We're not lifting SETFSUUID from ext4 -
that can be done on offline filesystems by the people who need it,
trying to do it online is just asking for too much trouble.

Cc: Christian Brauner <[email protected]>
Cc: Jan Kara <[email protected]>
Cc: Dave Chinner <[email protected]>
Cc: Darrick J. Wong <[email protected]>
Cc: Theodore Ts'o <[email protected]>
Cc: [email protected]
Signed-off-by: Kent Overstreet <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>

0 files changed, 0 insertions, 0 deletions