1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_S390_FUTEX_H
3 #define _ASM_S390_FUTEX_H
4
5 #include <linux/uaccess.h>
6 #include <linux/futex.h>
7 #include <asm/asm-extable.h>
8 #include <asm/mmu_context.h>
9 #include <asm/errno.h>
10
11 #define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \
12 asm volatile( \
13 " sacf 256\n" \
14 "0: l %1,0(%6)\n" \
15 "1:"insn \
16 "2: cs %1,%2,0(%6)\n" \
17 "3: jl 1b\n" \
18 " lhi %0,0\n" \
19 "4: sacf 768\n" \
20 EX_TABLE(0b,4b) EX_TABLE(1b,4b) \
21 EX_TABLE(2b,4b) EX_TABLE(3b,4b) \
22 : "=d" (ret), "=&d" (oldval), "=&d" (newval), \
23 "=m" (*uaddr) \
24 : "" (-EFAULT), "d" (oparg), "a" (uaddr), \
25 "m" (*uaddr) : "cc");
26
27 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
28 u32 __user *uaddr)
29 {
30 int oldval = 0, newval, ret;
31
32 switch (op) {
33 case FUTEX_OP_SET:
34 __futex_atomic_op("lr %2,%5\n",
35 ret, oldval, newval, uaddr, oparg);
36 break;
37 case FUTEX_OP_ADD:
38 __futex_atomic_op("lr %2,%1\nar %2,%5\n",
39 ret, oldval, newval, uaddr, oparg);
40 break;
41 case FUTEX_OP_OR:
42 __futex_atomic_op("lr %2,%1\nor %2,%5\n",
43 ret, oldval, newval, uaddr, oparg);
44 break;
45 case FUTEX_OP_ANDN:
46 __futex_atomic_op("lr %2,%1\nnr %2,%5\n",
47 ret, oldval, newval, uaddr, oparg);
48 break;
49 case FUTEX_OP_XOR:
50 __futex_atomic_op("lr %2,%1\nxr %2,%5\n",
51 ret, oldval, newval, uaddr, oparg);
52 break;
53 default:
54 ret = -ENOSYS;
55 }
56
57 if (!ret)
58 *oval = oldval;
59
60 return ret;
61 }
62
63 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
64 u32 oldval, u32 newval)
65 {
66 int ret;
67
68 asm volatile(
69 " sacf 256\n"
70 "0: cs %1,%4,0(%5)\n"
71 "1: la %0,0\n"
72 "2: sacf 768\n"
73 EX_TABLE(0b,2b) EX_TABLE(1b,2b)
74 : "=d" (ret), "+d" (oldval), "=m" (*uaddr)
75 : "" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr)
76 : "cc", "memory");
77 *uval = oldval;
78 return ret;
79 }
80
81 #endif /* _ASM_S390_FUTEX_H */
82
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