fs: add the ability for statmount() to report the fs_subtype

/proc/self/mountinfo prints out the sb->s_subtype after the type. This
is particularly useful for disambiguating FUSE mounts (at least when the
userland driver bothers to set it). Add STATMOUNT_FS_SUBTYPE and claim
one of the __spare2 fields to point to the offset into the str[] array.

Reviewed-by: Jan Kara <[email protected]>
Reviewed-by: Ian Kent <[email protected]>
Signed-off-by: Jeff Layton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Acked-by: Miklos Szeredi <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

0 files changed, 0 insertions, 0 deletions