FS_MNT_DETACH
fsnotify_mnt(FS_MNT_DETACH, ns, mnt);
#define FS_MNT_MOVE (FS_MNT_ATTACH | FS_MNT_DETACH)
#define FSNOTIFY_MNT_EVENTS (FS_MNT_ATTACH | FS_MNT_DETACH)