diff options
Diffstat (limited to 'kernel/futex.c')
| -rw-r--r-- | kernel/futex.c | 45 |
1 files changed, 15 insertions, 30 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 7738154..237f14b 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -381,15 +381,16 @@ static struct futex_q *futex_top_waiter(struct futex_hash_bucket *hb, return NULL; } -static u32 cmpxchg_futex_value_locked(u32 __user *uaddr, u32 uval, u32 newval) +static int cmpxchg_futex_value_locked(u32 *curval, u32 __user *uaddr, + u32 uval, u32 newval) { - u32 curval; + int ret; pagefault_disable(); - curval = futex_atomic_cmpxchg_inatomic(uaddr, uval, newval); + ret = futex_atomic_cmpxchg_inatomic(curval, uaddr, uval, newval); pagefault_enable(); - return curval; + return ret; } static int get_futex_value_locked(u32 *dest, u32 __user *from) @@ -688,9 +689,7 @@ retry: if (set_waiters) newval |= FUTEX_WAITERS; - curval = cmpxchg_futex_value_locked(uaddr, 0, newval); - - if (unlikely(curval == -EFAULT)) + if (unlikely(cmpxchg_futex_value_locked(&curval, uaddr, 0, newval))) return -EFAULT; /* @@ -728,9 +727,7 @@ retry: lock_taken = 1; } - curval = cmpxchg_futex_value_locked(uaddr, uval, newval); - - if (unlikely(curval == -EFAULT)) + if (unlikely(cmpxchg_futex_value_locked(&curval, uaddr, uval, newval))) return -EFAULT; if (unlikely(curval != uval)) goto retry; @@ -843,9 +840,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this) newval = FUTEX_WAITERS | task_pid_vnr(new_owner); - curval = cmpxchg_futex_value_locked(uaddr, uval, newval); - - if (curval == -EFAULT) + if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) ret = -EFAULT; else if (curval != uval) ret = -EINVAL; @@ -880,10 +875,8 @@ static int unlock_futex_pi(u32 __user *uaddr, u32 uval) * There is no waiter, so we unlock the futex. The owner died * bit has not to be preserved here. We are the owner: */ - oldval = cmpxchg_futex_value_locked(uaddr, uval, 0); - - if (oldval == -EFAULT) - return oldval; + if (cmpxchg_futex_value_locked(&oldval, uaddr, uval, 0)) + return -EFAULT; if (oldval != uval) return -EAGAIN; @@ -1578,9 +1571,7 @@ retry: while (1) { newval = (uval & FUTEX_OWNER_DIED) | newtid; - curval = cmpxchg_futex_value_locked(uaddr, uval, newval); - - if (curval == -EFAULT) + if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) goto handle_fault; if (curval == uval) break; @@ -2073,11 +2064,8 @@ retry: * again. If it succeeds then we can return without waking * anyone else up: */ - if (!(uval & FUTEX_OWNER_DIED)) - uval = cmpxchg_futex_value_locked(uaddr, vpid, 0); - - - if (unlikely(uval == -EFAULT)) + if (!(uval & FUTEX_OWNER_DIED) && + cmpxchg_futex_value_locked(&uval, uaddr, vpid, 0)) goto pi_faulted; /* * Rare case: we managed to release the lock atomically, @@ -2464,9 +2452,7 @@ retry: * userspace. */ mval = (uval & FUTEX_WAITERS) | FUTEX_OWNER_DIED; - nval = futex_atomic_cmpxchg_inatomic(uaddr, uval, mval); - - if (nval == -EFAULT) + if (futex_atomic_cmpxchg_inatomic(&nval, uaddr, uval, mval)) return -1; if (nval != uval) @@ -2679,8 +2665,7 @@ static int __init futex_init(void) * implementation, the non-functional ones will return * -ENOSYS. */ - curval = cmpxchg_futex_value_locked(NULL, 0, 0); - if (curval == -EFAULT) + if (cmpxchg_futex_value_locked(&curval, NULL, 0, 0) == -EFAULT) futex_cmpxchg_enabled = 1; for (i = 0; i < ARRAY_SIZE(futex_queues); i++) { |