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linux-next/include/asm-parisc/futex.h
Carlos O'Donell 342a0497c2 [PARISC] Implement futex_atomic_cmpxchg_inatomic
Implement trivial futex_atomic_cmpxchg_inatomic for testing.

Signed-off-by: Carlos O'Donell <carlos@systemhalted.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-10-04 06:47:36 -06:00

72 lines
1.5 KiB
C

#ifndef _ASM_PARISC_FUTEX_H
#define _ASM_PARISC_FUTEX_H
#ifdef __KERNEL__
#include <linux/futex.h>
#include <asm/errno.h>
#include <asm/uaccess.h>
static inline int
futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
{
int op = (encoded_op >> 28) & 7;
int cmp = (encoded_op >> 24) & 15;
int oparg = (encoded_op << 8) >> 20;
int cmparg = (encoded_op << 20) >> 20;
int oldval = 0, ret;
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
oparg = 1 << oparg;
if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
return -EFAULT;
inc_preempt_count();
switch (op) {
case FUTEX_OP_SET:
case FUTEX_OP_ADD:
case FUTEX_OP_OR:
case FUTEX_OP_ANDN:
case FUTEX_OP_XOR:
default:
ret = -ENOSYS;
}
dec_preempt_count();
if (!ret) {
switch (cmp) {
case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
default: ret = -ENOSYS;
}
}
return ret;
}
/* Non-atomic version */
static inline int
futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
{
int err = 0;
int uval;
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
return -EFAULT;
err = get_user(uval, uaddr);
if (err) return -EFAULT;
if (uval == oldval)
err = put_user(newval, uaddr);
if (err) return -EFAULT;
return uval;
}
#endif
#endif