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#ifndef _ASM_FUTEX_H
#define _ASM_FUTEX_H
#ifdef __KERNEL__
#include <linux/futex.h>
#include <asm/errno.h>
#include <asm/synch.h>
#include <asm/uaccess.h>
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
__asm__ __volatile (SYNC_ON_SMP \
"1: lwarx %0,0,%2\n" \
insn \
"2: stwcx. %1,0,%2\n\
bne- 1b\n\
li %1,0\n\
3: .section .fixup,\"ax\"\n\
4: li %1,%3\n\
b 3b\n\
.previous\n\
.section __ex_table,\"a\"\n\
.align 3\n\
.llong 1b,4b,2b,4b\n\
.previous" \
: "=&r" (oldval), "=&r" (ret) \
: "b" (uaddr), "i" (-EFAULT), "1" (oparg) \
: "cr0", "memory")
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:
__futex_atomic_op("", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("add %1,%0,%1\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("or %1,%0,%1\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("andc %1,%0,%1\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("xor %1,%0,%1\n", ret, oldval, uaddr, oparg);
break;
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;
}
#endif
#endif
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