btrfs: Make extent-io callbacks that never fail return void
The set/clear bit and the extent split/merge hooks only ever return 0.
Changing them to return void simplifies the error handling cases later.
This patch changes the hook prototypes, the single implementation of each,
and the functions that call them to return void instead.
Since all four of these hooks execute under a spinlock, they're necessarily
simple.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
3 files changed