rw_semaphore: remove up/down_read_non_owner

Now that the last users is gone these can be removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

include/linux/rwsem.h

@@ -124,19 +124,9 @@ extern void downgrade_write(struct rw_semaphore *sem);
  */
 extern void down_read_nested(struct rw_semaphore *sem, int subclass);
 extern void down_write_nested(struct rw_semaphore *sem, int subclass);
-/*
- * Take/release a lock when not the owner will release it.
- *
- * [ This API should be avoided as much as possible - the
- *   proper abstraction for this case is completions. ]
- */
-extern void down_read_non_owner(struct rw_semaphore *sem);
-extern void up_read_non_owner(struct rw_semaphore *sem);
 #else
 # define down_read_nested(sem, subclass)		down_read(sem)
 # define down_write_nested(sem, subclass)	down_write(sem)
-# define down_read_non_owner(sem)		down_read(sem)
-# define up_read_non_owner(sem)			up_read(sem)
 #endif
 
 #endif /* _LINUX_RWSEM_H */

kernel/rwsem.c

@@ -117,15 +117,6 @@ void down_read_nested(struct rw_semaphore *sem, int subclass)
 
 EXPORT_SYMBOL(down_read_nested);
 
-void down_read_non_owner(struct rw_semaphore *sem)
-{
-	might_sleep();
-
-	__down_read(sem);
-}
-
-EXPORT_SYMBOL(down_read_non_owner);
-
 void down_write_nested(struct rw_semaphore *sem, int subclass)
 {
 	might_sleep();
@@ -136,13 +127,6 @@ void down_write_nested(struct rw_semaphore *sem, int subclass)
 
 EXPORT_SYMBOL(down_write_nested);
 
-void up_read_non_owner(struct rw_semaphore *sem)
-{
-	__up_read(sem);
-}
-
-EXPORT_SYMBOL(up_read_non_owner);
-
 #endif