106 lines
2.4 KiB
C
Executable file
106 lines
2.4 KiB
C
Executable file
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_POWERPC_FUTEX_H
|
|
#define _ASM_POWERPC_FUTEX_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/futex.h>
|
|
#include <linux/uaccess.h>
|
|
#include <asm/errno.h>
|
|
#include <asm/synch.h>
|
|
#include <asm/asm-405.h>
|
|
|
|
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
|
|
__asm__ __volatile ( \
|
|
PPC_ATOMIC_ENTRY_BARRIER \
|
|
"1: lwarx %0,0,%2\n" \
|
|
insn \
|
|
PPC405_ERR77(0, %2) \
|
|
"2: stwcx. %1,0,%2\n" \
|
|
"bne- 1b\n" \
|
|
PPC_ATOMIC_EXIT_BARRIER \
|
|
"li %1,0\n" \
|
|
"3: .section .fixup,\"ax\"\n" \
|
|
"4: li %1,%3\n" \
|
|
"b 3b\n" \
|
|
".previous\n" \
|
|
EX_TABLE(1b, 4b) \
|
|
EX_TABLE(2b, 4b) \
|
|
: "=&r" (oldval), "=&r" (ret) \
|
|
: "b" (uaddr), "i" (-EFAULT), "r" (oparg) \
|
|
: "cr0", "memory")
|
|
|
|
static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
|
|
u32 __user *uaddr)
|
|
{
|
|
int oldval = 0, ret;
|
|
|
|
allow_write_to_user(uaddr, sizeof(*uaddr));
|
|
pagefault_disable();
|
|
|
|
switch (op) {
|
|
case FUTEX_OP_SET:
|
|
__futex_atomic_op("mr %1,%4\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ADD:
|
|
__futex_atomic_op("add %1,%0,%4\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_OR:
|
|
__futex_atomic_op("or %1,%0,%4\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ANDN:
|
|
__futex_atomic_op("andc %1,%0,%4\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_XOR:
|
|
__futex_atomic_op("xor %1,%0,%4\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
default:
|
|
ret = -ENOSYS;
|
|
}
|
|
|
|
pagefault_enable();
|
|
|
|
*oval = oldval;
|
|
|
|
prevent_write_to_user(uaddr, sizeof(*uaddr));
|
|
return ret;
|
|
}
|
|
|
|
static inline int
|
|
futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
|
|
u32 oldval, u32 newval)
|
|
{
|
|
int ret = 0;
|
|
u32 prev;
|
|
|
|
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
|
|
return -EFAULT;
|
|
|
|
allow_write_to_user(uaddr, sizeof(*uaddr));
|
|
__asm__ __volatile__ (
|
|
PPC_ATOMIC_ENTRY_BARRIER
|
|
"1: lwarx %1,0,%3 # futex_atomic_cmpxchg_inatomic\n\
|
|
cmpw 0,%1,%4\n\
|
|
bne- 3f\n"
|
|
PPC405_ERR77(0,%3)
|
|
"2: stwcx. %5,0,%3\n\
|
|
bne- 1b\n"
|
|
PPC_ATOMIC_EXIT_BARRIER
|
|
"3: .section .fixup,\"ax\"\n\
|
|
4: li %0,%6\n\
|
|
b 3b\n\
|
|
.previous\n"
|
|
EX_TABLE(1b, 4b)
|
|
EX_TABLE(2b, 4b)
|
|
: "+r" (ret), "=&r" (prev), "+m" (*uaddr)
|
|
: "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT)
|
|
: "cc", "memory");
|
|
|
|
*uval = prev;
|
|
prevent_write_to_user(uaddr, sizeof(*uaddr));
|
|
return ret;
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _ASM_POWERPC_FUTEX_H */
|