1 /* Public domain. */ 2 3 #ifndef _LINUX_RWSEM_H 4 #define _LINUX_RWSEM_H 5 6 #define down_read(rwl) rw_enter_read(rwl) 7 #define down_read_trylock(rwl) (rw_enter(rwl, RW_READ | RW_NOSLEEP) == 0) 8 #define down_write_trylock(rwl) (rw_enter(rwl, RW_WRITE | RW_NOSLEEP) == 0) 9 #define up_read(rwl) rw_exit_read(rwl) 10 #define down_write(rwl) rw_enter_write(rwl) 11 #define down_write_nest_lock(rwl, x) rw_enter_write(rwl) 12 #define up_write(rwl) rw_exit_write(rwl) 13 #define downgrade_write(rwl) rw_enter(rwl, RW_DOWNGRADE) 14 15 #define DECLARE_RWSEM(rwl) \ 16 struct rwlock rwl = RWLOCK_INITIALIZER(#rwl) 17 /* no interface to check if another caller wants the lock */ 18 #define rwsem_is_contended(rwl) 0 19 20 #endif 21