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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_ALPHA_FUTEX_H
#define _ASM_ALPHA_FUTEX_H
#ifdef __KERNEL__
#include <linux/futex.h>
#include <linux/uaccess.h>
#include <asm/errno.h>
#include <asm/barrier.h>
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
__asm__ __volatile__( \
__ASM_SMP_MB \
"1: ldl_l %0,0(%2)\n" \
insn \
"2: stl_c %1,0(%2)\n" \
" beq %1,4f\n" \
" mov $31,%1\n" \
"3: .subsection 2\n" \
"4: br 1b\n" \
" .previous\n" \
EXC(1b,3b,$31,%1) \
EXC(2b,3b,$31,%1) \
: "=&r" (oldval), "=&r"(ret) \
: "r" (uaddr), "r"(oparg) \
: "memory")
static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
u32 __user *uaddr)
{
int oldval = 0, ret;
pagefault_disable();
switch (op) {
case FUTEX_OP_SET:
__futex_atomic_op("mov %3,%1\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("addl %0,%3,%1\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("or %0,%3,%1\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("andnot %0,%3,%1\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("xor %0,%3,%1\n", ret, oldval, uaddr, oparg);
break;
default:
ret = -ENOSYS;
}
pagefault_enable();
if (!ret)
*oval = oldval;
return ret;
}
static inline int
futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
u32 oldval, u32 newval)
{
int ret = 0, cmp;
u32 prev;
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
return -EFAULT;
__asm__ __volatile__ (
__ASM_SMP_MB
"1: ldl_l %1,0(%3)\n"
" cmpeq %1,%4,%2\n"
" beq %2,3f\n"
" mov %5,%2\n"
"2: stl_c %2,0(%3)\n"
" beq %2,4f\n"
"3: .subsection 2\n"
"4: br 1b\n"
" .previous\n"
EXC(1b,3b,$31,%0)
EXC(2b,3b,$31,%0)
: "+r"(ret), "=&r"(prev), "=&r"(cmp)
: "r"(uaddr), "r"((long)(int)oldval), "r"(newval)
: "memory");
*uval = prev;
return ret;
}
#endif /* __KERNEL__ */
#endif /* _ASM_ALPHA_FUTEX_H */
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