kernel-ark/include/asm-generic/futex.h
Ingo Molnar 8f17d3a504 [PATCH] lightweight robust futexes updates
- fix: initialize the robust list(s) to NULL in copy_process.

- doc update

- cleanup: rename _inuser to _inatomic

- __user cleanups and other small cleanups

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:49 -08:00

60 lines
1.3 KiB
C

#ifndef _ASM_GENERIC_FUTEX_H
#define _ASM_GENERIC_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;
}
static inline int
futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
{
return -ENOSYS;
}
#endif
#endif