-extern struct swap_list_t swap_list;
-extern spinlock_t swaplock;
-
-#define swap_list_lock() spin_lock(&swaplock)
-#define swap_list_unlock() spin_unlock(&swaplock)
-#define swap_device_lock(p) spin_lock(&p->sdev_lock)
-#define swap_device_unlock(p) spin_unlock(&p->sdev_lock)