xref: /openbmc/linux/arch/sparc/include/asm/futex_64.h (revision e7bae9bb)
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 	switch (op) {
42 	case FUTEX_OP_SET:
43 		__futex_cas_op("mov\t%4, %1", ret, oldval, uaddr, oparg);
44 		break;
45 	case FUTEX_OP_ADD:
46 		__futex_cas_op("add\t%2, %4, %1", ret, oldval, uaddr, oparg);
47 		break;
48 	case FUTEX_OP_OR:
49 		__futex_cas_op("or\t%2, %4, %1", ret, oldval, uaddr, oparg);
50 		break;
51 	case FUTEX_OP_ANDN:
52 		__futex_cas_op("andn\t%2, %4, %1", ret, oldval, uaddr, oparg);
53 		break;
54 	case FUTEX_OP_XOR:
55 		__futex_cas_op("xor\t%2, %4, %1", ret, oldval, uaddr, oparg);
56 		break;
57 	default:
58 		ret = -ENOSYS;
59 	}
60 
61 	if (!ret)
62 		*oval = oldval;
63 
64 	return ret;
65 }
66 
67 static inline int
68 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
69 			      u32 oldval, u32 newval)
70 {
71 	int ret = 0;
72 
73 	__asm__ __volatile__(
74 	"\n1:	casa	[%4] %%asi, %3, %1\n"
75 	"2:\n"
76 	"	.section .fixup,#alloc,#execinstr\n"
77 	"	.align	4\n"
78 	"3:	sethi	%%hi(2b), %0\n"
79 	"	jmpl	%0 + %%lo(2b), %%g0\n"
80 	"	mov	%5, %0\n"
81 	"	.previous\n"
82 	"	.section __ex_table,\"a\"\n"
83 	"	.align	4\n"
84 	"	.word	1b, 3b\n"
85 	"	.previous\n"
86 	: "+r" (ret), "=r" (newval)
87 	: "1" (newval), "r" (oldval), "r" (uaddr), "i" (-EFAULT)
88 	: "memory");
89 
90 	*uval = newval;
91 	return ret;
92 }
93 
94 #endif /* !(_SPARC64_FUTEX_H) */
95