xref: /openbmc/linux/arch/sparc/include/asm/futex_64.h (revision 82e6fdd6)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _SPARC64_FUTEX_H
3 #define _SPARC64_FUTEX_H
4 
5 #include <linux/futex.h>
6 #include <linux/uaccess.h>
7 #include <asm/errno.h>
8 
9 #define __futex_cas_op(insn, ret, oldval, uaddr, oparg)	\
10 	__asm__ __volatile__(				\
11 	"\n1:	lduwa	[%3] %%asi, %2\n"		\
12 	"	" insn "\n"				\
13 	"2:	casa	[%3] %%asi, %2, %1\n"		\
14 	"	cmp	%2, %1\n"			\
15 	"	bne,pn	%%icc, 1b\n"			\
16 	"	 mov	0, %0\n"			\
17 	"3:\n"						\
18 	"	.section .fixup,#alloc,#execinstr\n"	\
19 	"	.align	4\n"				\
20 	"4:	sethi	%%hi(3b), %0\n"			\
21 	"	jmpl	%0 + %%lo(3b), %%g0\n"		\
22 	"	 mov	%5, %0\n"			\
23 	"	.previous\n"				\
24 	"	.section __ex_table,\"a\"\n"		\
25 	"	.align	4\n"				\
26 	"	.word	1b, 4b\n"			\
27 	"	.word	2b, 4b\n"			\
28 	"	.previous\n"				\
29 	: "=&r" (ret), "=&r" (oldval), "=&r" (tem)	\
30 	: "r" (uaddr), "r" (oparg), "i" (-EFAULT)	\
31 	: "memory")
32 
33 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
34 		u32 __user *uaddr)
35 {
36 	int oldval = 0, ret, tem;
37 
38 	if (unlikely((((unsigned long) uaddr) & 0x3UL)))
39 		return -EINVAL;
40 
41 	pagefault_disable();
42 
43 	switch (op) {
44 	case FUTEX_OP_SET:
45 		__futex_cas_op("mov\t%4, %1", ret, oldval, uaddr, oparg);
46 		break;
47 	case FUTEX_OP_ADD:
48 		__futex_cas_op("add\t%2, %4, %1", ret, oldval, uaddr, oparg);
49 		break;
50 	case FUTEX_OP_OR:
51 		__futex_cas_op("or\t%2, %4, %1", ret, oldval, uaddr, oparg);
52 		break;
53 	case FUTEX_OP_ANDN:
54 		__futex_cas_op("andn\t%2, %4, %1", ret, oldval, uaddr, oparg);
55 		break;
56 	case FUTEX_OP_XOR:
57 		__futex_cas_op("xor\t%2, %4, %1", ret, oldval, uaddr, oparg);
58 		break;
59 	default:
60 		ret = -ENOSYS;
61 	}
62 
63 	pagefault_enable();
64 
65 	if (!ret)
66 		*oval = oldval;
67 
68 	return ret;
69 }
70 
71 static inline int
72 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
73 			      u32 oldval, u32 newval)
74 {
75 	int ret = 0;
76 
77 	__asm__ __volatile__(
78 	"\n1:	casa	[%4] %%asi, %3, %1\n"
79 	"2:\n"
80 	"	.section .fixup,#alloc,#execinstr\n"
81 	"	.align	4\n"
82 	"3:	sethi	%%hi(2b), %0\n"
83 	"	jmpl	%0 + %%lo(2b), %%g0\n"
84 	"	mov	%5, %0\n"
85 	"	.previous\n"
86 	"	.section __ex_table,\"a\"\n"
87 	"	.align	4\n"
88 	"	.word	1b, 3b\n"
89 	"	.previous\n"
90 	: "+r" (ret), "=r" (newval)
91 	: "1" (newval), "r" (oldval), "r" (uaddr), "i" (-EFAULT)
92 	: "memory");
93 
94 	*uval = newval;
95 	return ret;
96 }
97 
98 #endif /* !(_SPARC64_FUTEX_H) */
99