99 строки
2.4 KiB
C
99 строки
2.4 KiB
C
#ifndef _ASM_FUTEX_H
|
|
#define _ASM_FUTEX_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/futex.h>
|
|
#include <asm/errno.h>
|
|
#include <asm/system.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
|
|
__asm__ __volatile ( \
|
|
"1: " insn "\n" \
|
|
"2: .section .fixup,\"ax\"\n\
|
|
3: mov %3, %1\n\
|
|
jmp 2b\n\
|
|
.previous\n\
|
|
.section __ex_table,\"a\"\n\
|
|
.align 8\n\
|
|
.quad 1b,3b\n\
|
|
.previous" \
|
|
: "=r" (oldval), "=r" (ret), "=m" (*uaddr) \
|
|
: "i" (-EFAULT), "m" (*uaddr), "0" (oparg), "1" (0))
|
|
|
|
#define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
|
|
__asm__ __volatile ( \
|
|
"1: movl %2, %0\n\
|
|
movl %0, %3\n" \
|
|
insn "\n" \
|
|
"2: " LOCK_PREFIX "cmpxchgl %3, %2\n\
|
|
jnz 1b\n\
|
|
3: .section .fixup,\"ax\"\n\
|
|
4: mov %5, %1\n\
|
|
jmp 3b\n\
|
|
.previous\n\
|
|
.section __ex_table,\"a\"\n\
|
|
.align 8\n\
|
|
.quad 1b,4b,2b,4b\n\
|
|
.previous" \
|
|
: "=&a" (oldval), "=&r" (ret), "=m" (*uaddr), \
|
|
"=&r" (tem) \
|
|
: "r" (oparg), "i" (-EFAULT), "m" (*uaddr), "1" (0))
|
|
|
|
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, tem;
|
|
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_op1("xchgl %0, %2", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ADD:
|
|
__futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval,
|
|
uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_OR:
|
|
__futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ANDN:
|
|
__futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg);
|
|
break;
|
|
case FUTEX_OP_XOR:
|
|
__futex_atomic_op2("xorl %4, %3", 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
|