Commit 27b88f35 authored by peterz@infradead.org's avatar peterz@infradead.org Committed by Peter Zijlstra
Browse files

futex: Add flags2 argument to futex_requeue() 



In order to support mixed size requeue, add a second flags argument to
the internal futex_requeue() function.

No functional change intended.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230921105248.396780136@noisy.programming.kicks-ass.net
parent 3b63a55f

kernel/futex/futex.h

+3 −2
Original line number Diff line number Diff line
@@ -328,8 +328,9 @@ extern int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, u32 
				 val, ktime_t *abs_time, u32 bitset, u32 __user

				 *uaddr2);



extern int futex_requeue(u32 __user *uaddr1, unsigned int flags,

			 u32 __user *uaddr2, int nr_wake, int nr_requeue,

extern int futex_requeue(u32 __user *uaddr1, unsigned int flags1,

			 u32 __user *uaddr2, unsigned int flags2,

			 int nr_wake, int nr_requeue,

			 u32 *cmpval, int requeue_pi);



extern int __futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,

kernel/futex/requeue.c

+7 −5
Original line number Diff line number Diff line
@@ -346,8 +346,9 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1, 
/**

 * futex_requeue() - Requeue waiters from uaddr1 to uaddr2

 * @uaddr1:	source futex user address

 * @flags:	futex flags (FLAGS_SHARED, etc.)

 * @flags1:	futex flags (FLAGS_SHARED, etc.)

 * @uaddr2:	target futex user address

 * @flags2:	futex flags (FLAGS_SHARED, etc.)

 * @nr_wake:	number of waiters to wake (must be 1 for requeue_pi)

 * @nr_requeue:	number of waiters to requeue (0-INT_MAX)

 * @cmpval:	@uaddr1 expected value (or %NULL)
@@ -361,7 +362,8 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1, 
 *  - >=0 - on success, the number of tasks requeued or woken;

 *  -  <0 - on error

 */

int futex_requeue(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,

int futex_requeue(u32 __user *uaddr1, unsigned int flags1,

		  u32 __user *uaddr2, unsigned int flags2,

		  int nr_wake, int nr_requeue, u32 *cmpval, int requeue_pi)

{

	union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT;
@@ -424,10 +426,10 @@ int futex_requeue(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, 
	}



retry:

	ret = get_futex_key(uaddr1, flags, &key1, FUTEX_READ);

	ret = get_futex_key(uaddr1, flags1, &key1, FUTEX_READ);

	if (unlikely(ret != 0))

		return ret;

	ret = get_futex_key(uaddr2, flags, &key2,

	ret = get_futex_key(uaddr2, flags2, &key2,

			    requeue_pi ? FUTEX_WRITE : FUTEX_READ);

	if (unlikely(ret != 0))

		return ret;
@@ -459,7 +461,7 @@ int futex_requeue(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, 
			if (ret)

				return ret;



			if (!(flags & FLAGS_SHARED))

			if (!(flags1 & FLAGS_SHARED))

				goto retry_private;



			goto retry;

kernel/futex/syscalls.c

+3 −3
Original line number Diff line number Diff line
@@ -106,9 +106,9 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, 
	case FUTEX_WAKE_BITSET:

		return futex_wake(uaddr, flags, val, val3);

	case FUTEX_REQUEUE:

		return futex_requeue(uaddr, flags, uaddr2, val, val2, NULL, 0);

		return futex_requeue(uaddr, flags, uaddr2, flags, val, val2, NULL, 0);

	case FUTEX_CMP_REQUEUE:

		return futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 0);

		return futex_requeue(uaddr, flags, uaddr2, flags, val, val2, &val3, 0);

	case FUTEX_WAKE_OP:

		return futex_wake_op(uaddr, flags, uaddr2, val, val2, val3);

	case FUTEX_LOCK_PI:
@@ -125,7 +125,7 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, 
		return futex_wait_requeue_pi(uaddr, flags, val, timeout, val3,

					     uaddr2);

	case FUTEX_CMP_REQUEUE_PI:

		return futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 1);

		return futex_requeue(uaddr, flags, uaddr2, flags, val, val2, &val3, 1);

	}

	return -ENOSYS;

}