xref: /OK3568_Linux_fs/kernel/arch/alpha/include/asm/futex.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef _ASM_ALPHA_FUTEX_H
3*4882a593Smuzhiyun #define _ASM_ALPHA_FUTEX_H
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun #ifdef __KERNEL__
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #include <linux/futex.h>
8*4882a593Smuzhiyun #include <linux/uaccess.h>
9*4882a593Smuzhiyun #include <asm/errno.h>
10*4882a593Smuzhiyun #include <asm/barrier.h>
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg)	\
13*4882a593Smuzhiyun 	__asm__ __volatile__(					\
14*4882a593Smuzhiyun 		__ASM_SMP_MB					\
15*4882a593Smuzhiyun 	"1:	ldl_l	%0,0(%2)\n"				\
16*4882a593Smuzhiyun 		insn						\
17*4882a593Smuzhiyun 	"2:	stl_c	%1,0(%2)\n"				\
18*4882a593Smuzhiyun 	"	beq	%1,4f\n"				\
19*4882a593Smuzhiyun 	"	mov	$31,%1\n"				\
20*4882a593Smuzhiyun 	"3:	.subsection 2\n"				\
21*4882a593Smuzhiyun 	"4:	br	1b\n"					\
22*4882a593Smuzhiyun 	"	.previous\n"					\
23*4882a593Smuzhiyun 	EXC(1b,3b,$31,%1)					\
24*4882a593Smuzhiyun 	EXC(2b,3b,$31,%1)					\
25*4882a593Smuzhiyun 	:	"=&r" (oldval), "=&r"(ret)			\
26*4882a593Smuzhiyun 	:	"r" (uaddr), "r"(oparg)				\
27*4882a593Smuzhiyun 	:	"memory")
28*4882a593Smuzhiyun 
arch_futex_atomic_op_inuser(int op,int oparg,int * oval,u32 __user * uaddr)29*4882a593Smuzhiyun static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
30*4882a593Smuzhiyun 		u32 __user *uaddr)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun 	int oldval = 0, ret;
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun 	if (!access_ok(uaddr, sizeof(u32)))
35*4882a593Smuzhiyun 		return -EFAULT;
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun 	switch (op) {
38*4882a593Smuzhiyun 	case FUTEX_OP_SET:
39*4882a593Smuzhiyun 		__futex_atomic_op("mov %3,%1\n", ret, oldval, uaddr, oparg);
40*4882a593Smuzhiyun 		break;
41*4882a593Smuzhiyun 	case FUTEX_OP_ADD:
42*4882a593Smuzhiyun 		__futex_atomic_op("addl %0,%3,%1\n", ret, oldval, uaddr, oparg);
43*4882a593Smuzhiyun 		break;
44*4882a593Smuzhiyun 	case FUTEX_OP_OR:
45*4882a593Smuzhiyun 		__futex_atomic_op("or %0,%3,%1\n", ret, oldval, uaddr, oparg);
46*4882a593Smuzhiyun 		break;
47*4882a593Smuzhiyun 	case FUTEX_OP_ANDN:
48*4882a593Smuzhiyun 		__futex_atomic_op("andnot %0,%3,%1\n", ret, oldval, uaddr, oparg);
49*4882a593Smuzhiyun 		break;
50*4882a593Smuzhiyun 	case FUTEX_OP_XOR:
51*4882a593Smuzhiyun 		__futex_atomic_op("xor %0,%3,%1\n", ret, oldval, uaddr, oparg);
52*4882a593Smuzhiyun 		break;
53*4882a593Smuzhiyun 	default:
54*4882a593Smuzhiyun 		ret = -ENOSYS;
55*4882a593Smuzhiyun 	}
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun 	if (!ret)
58*4882a593Smuzhiyun 		*oval = oldval;
59*4882a593Smuzhiyun 
60*4882a593Smuzhiyun 	return ret;
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun static inline int
futex_atomic_cmpxchg_inatomic(u32 * uval,u32 __user * uaddr,u32 oldval,u32 newval)64*4882a593Smuzhiyun futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
65*4882a593Smuzhiyun 			      u32 oldval, u32 newval)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun 	int ret = 0, cmp;
68*4882a593Smuzhiyun 	u32 prev;
69*4882a593Smuzhiyun 
70*4882a593Smuzhiyun 	if (!access_ok(uaddr, sizeof(u32)))
71*4882a593Smuzhiyun 		return -EFAULT;
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun 	__asm__ __volatile__ (
74*4882a593Smuzhiyun 		__ASM_SMP_MB
75*4882a593Smuzhiyun 	"1:	ldl_l	%1,0(%3)\n"
76*4882a593Smuzhiyun 	"	cmpeq	%1,%4,%2\n"
77*4882a593Smuzhiyun 	"	beq	%2,3f\n"
78*4882a593Smuzhiyun 	"	mov	%5,%2\n"
79*4882a593Smuzhiyun 	"2:	stl_c	%2,0(%3)\n"
80*4882a593Smuzhiyun 	"	beq	%2,4f\n"
81*4882a593Smuzhiyun 	"3:	.subsection 2\n"
82*4882a593Smuzhiyun 	"4:	br	1b\n"
83*4882a593Smuzhiyun 	"	.previous\n"
84*4882a593Smuzhiyun 	EXC(1b,3b,$31,%0)
85*4882a593Smuzhiyun 	EXC(2b,3b,$31,%0)
86*4882a593Smuzhiyun 	:	"+r"(ret), "=&r"(prev), "=&r"(cmp)
87*4882a593Smuzhiyun 	:	"r"(uaddr), "r"((long)(int)oldval), "r"(newval)
88*4882a593Smuzhiyun 	:	"memory");
89*4882a593Smuzhiyun 
90*4882a593Smuzhiyun 	*uval = prev;
91*4882a593Smuzhiyun 	return ret;
92*4882a593Smuzhiyun }
93*4882a593Smuzhiyun 
94*4882a593Smuzhiyun #endif /* __KERNEL__ */
95*4882a593Smuzhiyun #endif /* _ASM_ALPHA_FUTEX_H */
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