linux/arch/alpha/include/asm/futex.h
Al Viro a08971e948 futex: arch_futex_atomic_op_inuser() calling conventions change
Move access_ok() in and pagefault_enable()/pagefault_disable() out.
Mechanical conversion only - some instances don't really need
a separate access_ok() at all (e.g. the ones only using
get_user()/put_user(), or architectures where access_ok()
is always true); we'll deal with that in followups.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-27 23:58:51 -04:00

96 lines
2.0 KiB
C

/* 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;
if (!access_ok(uaddr, sizeof(u32)))
return -EFAULT;
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;
}
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(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 */