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/mmu_context.h>
8 #include <asm/errno.h>
9
10 #define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \
11 asm volatile( \
12 " sacf 256\n" \
13 "0: l %1,0(%6)\n" \
14 "1:"insn \
15 "2: cs %1,%2,0(%6)\n" \
16 "3: jl 1b\n" \
17 " lhi %0,0\n" \
18 "4: sacf 768\n" \
19 EX_TABLE(0b,4b) EX_TABLE(1b,4b) \
20 EX_TABLE(2b,4b) EX_TABLE(3b,4b) \
21 : "=d" (ret), "=&d" (oldval), "=&d" (newval), \
22 "=m" (*uaddr) \
23 : "0" (-EFAULT), "d" (oparg), "a" (uaddr), \
24 "m" (*uaddr) : "cc");
25
arch_futex_atomic_op_inuser(int op,int oparg,int * oval,u32 __user * uaddr)26 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
27 u32 __user *uaddr)
28 {
29 int oldval = 0, newval, ret;
30 mm_segment_t old_fs;
31
32 old_fs = enable_sacf_uaccess();
33 pagefault_disable();
34 switch (op) {
35 case FUTEX_OP_SET:
36 __futex_atomic_op("lr %2,%5\n",
37 ret, oldval, newval, uaddr, oparg);
38 break;
39 case FUTEX_OP_ADD:
40 __futex_atomic_op("lr %2,%1\nar %2,%5\n",
41 ret, oldval, newval, uaddr, oparg);
42 break;
43 case FUTEX_OP_OR:
44 __futex_atomic_op("lr %2,%1\nor %2,%5\n",
45 ret, oldval, newval, uaddr, oparg);
46 break;
47 case FUTEX_OP_ANDN:
48 __futex_atomic_op("lr %2,%1\nnr %2,%5\n",
49 ret, oldval, newval, uaddr, oparg);
50 break;
51 case FUTEX_OP_XOR:
52 __futex_atomic_op("lr %2,%1\nxr %2,%5\n",
53 ret, oldval, newval, uaddr, oparg);
54 break;
55 default:
56 ret = -ENOSYS;
57 }
58 pagefault_enable();
59 disable_sacf_uaccess(old_fs);
60
61 if (!ret)
62 *oval = oldval;
63
64 return ret;
65 }
66
futex_atomic_cmpxchg_inatomic(u32 * uval,u32 __user * uaddr,u32 oldval,u32 newval)67 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
68 u32 oldval, u32 newval)
69 {
70 mm_segment_t old_fs;
71 int ret;
72
73 old_fs = enable_sacf_uaccess();
74 asm volatile(
75 " sacf 256\n"
76 "0: cs %1,%4,0(%5)\n"
77 "1: la %0,0\n"
78 "2: sacf 768\n"
79 EX_TABLE(0b,2b) EX_TABLE(1b,2b)
80 : "=d" (ret), "+d" (oldval), "=m" (*uaddr)
81 : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr)
82 : "cc", "memory");
83 disable_sacf_uaccess(old_fs);
84 *uval = oldval;
85 return ret;
86 }
87
88 #endif /* _ASM_S390_FUTEX_H */
89