1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun // Copyright (C) 2005-2017 Andes Technology Corporation
3*4882a593Smuzhiyun
4*4882a593Smuzhiyun #ifndef __NDS32_FUTEX_H__
5*4882a593Smuzhiyun #define __NDS32_FUTEX_H__
6*4882a593Smuzhiyun
7*4882a593Smuzhiyun #include <linux/futex.h>
8*4882a593Smuzhiyun #include <linux/uaccess.h>
9*4882a593Smuzhiyun #include <asm/errno.h>
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #define __futex_atomic_ex_table(err_reg) \
12*4882a593Smuzhiyun " .pushsection __ex_table,\"a\"\n" \
13*4882a593Smuzhiyun " .align 3\n" \
14*4882a593Smuzhiyun " .long 1b, 4f\n" \
15*4882a593Smuzhiyun " .long 2b, 4f\n" \
16*4882a593Smuzhiyun " .popsection\n" \
17*4882a593Smuzhiyun " .pushsection .fixup,\"ax\"\n" \
18*4882a593Smuzhiyun "4: move %0, " err_reg "\n" \
19*4882a593Smuzhiyun " b 3b\n" \
20*4882a593Smuzhiyun " .popsection"
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun #define __futex_atomic_op(insn, ret, oldval, tmp, uaddr, oparg) \
23*4882a593Smuzhiyun smp_mb(); \
24*4882a593Smuzhiyun asm volatile( \
25*4882a593Smuzhiyun " movi $ta, #0\n" \
26*4882a593Smuzhiyun "1: llw %1, [%2+$ta]\n" \
27*4882a593Smuzhiyun " " insn "\n" \
28*4882a593Smuzhiyun "2: scw %0, [%2+$ta]\n" \
29*4882a593Smuzhiyun " beqz %0, 1b\n" \
30*4882a593Smuzhiyun " movi %0, #0\n" \
31*4882a593Smuzhiyun "3:\n" \
32*4882a593Smuzhiyun __futex_atomic_ex_table("%4") \
33*4882a593Smuzhiyun : "=&r" (ret), "=&r" (oldval) \
34*4882a593Smuzhiyun : "r" (uaddr), "r" (oparg), "i" (-EFAULT) \
35*4882a593Smuzhiyun : "cc", "memory")
36*4882a593Smuzhiyun static inline int
futex_atomic_cmpxchg_inatomic(u32 * uval,u32 __user * uaddr,u32 oldval,u32 newval)37*4882a593Smuzhiyun futex_atomic_cmpxchg_inatomic(u32 * uval, u32 __user * uaddr,
38*4882a593Smuzhiyun u32 oldval, u32 newval)
39*4882a593Smuzhiyun {
40*4882a593Smuzhiyun int ret = 0;
41*4882a593Smuzhiyun u32 val, tmp, flags;
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun if (!access_ok(uaddr, sizeof(u32)))
44*4882a593Smuzhiyun return -EFAULT;
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun smp_mb();
47*4882a593Smuzhiyun asm volatile (" movi $ta, #0\n"
48*4882a593Smuzhiyun "1: llw %1, [%6 + $ta]\n"
49*4882a593Smuzhiyun " sub %3, %1, %4\n"
50*4882a593Smuzhiyun " cmovz %2, %5, %3\n"
51*4882a593Smuzhiyun " cmovn %2, %1, %3\n"
52*4882a593Smuzhiyun "2: scw %2, [%6 + $ta]\n"
53*4882a593Smuzhiyun " beqz %2, 1b\n"
54*4882a593Smuzhiyun "3:\n " __futex_atomic_ex_table("%7")
55*4882a593Smuzhiyun :"+&r"(ret), "=&r"(val), "=&r"(tmp), "=&r"(flags)
56*4882a593Smuzhiyun :"r"(oldval), "r"(newval), "r"(uaddr), "i"(-EFAULT)
57*4882a593Smuzhiyun :"$ta", "memory");
58*4882a593Smuzhiyun smp_mb();
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun *uval = val;
61*4882a593Smuzhiyun return ret;
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun static inline int
arch_futex_atomic_op_inuser(int op,int oparg,int * oval,u32 __user * uaddr)65*4882a593Smuzhiyun arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun int oldval = 0, ret;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun if (!access_ok(uaddr, sizeof(u32)))
70*4882a593Smuzhiyun return -EFAULT;
71*4882a593Smuzhiyun switch (op) {
72*4882a593Smuzhiyun case FUTEX_OP_SET:
73*4882a593Smuzhiyun __futex_atomic_op("move %0, %3", ret, oldval, tmp, uaddr,
74*4882a593Smuzhiyun oparg);
75*4882a593Smuzhiyun break;
76*4882a593Smuzhiyun case FUTEX_OP_ADD:
77*4882a593Smuzhiyun __futex_atomic_op("add %0, %1, %3", ret, oldval, tmp, uaddr,
78*4882a593Smuzhiyun oparg);
79*4882a593Smuzhiyun break;
80*4882a593Smuzhiyun case FUTEX_OP_OR:
81*4882a593Smuzhiyun __futex_atomic_op("or %0, %1, %3", ret, oldval, tmp, uaddr,
82*4882a593Smuzhiyun oparg);
83*4882a593Smuzhiyun break;
84*4882a593Smuzhiyun case FUTEX_OP_ANDN:
85*4882a593Smuzhiyun __futex_atomic_op("and %0, %1, %3", ret, oldval, tmp, uaddr,
86*4882a593Smuzhiyun ~oparg);
87*4882a593Smuzhiyun break;
88*4882a593Smuzhiyun case FUTEX_OP_XOR:
89*4882a593Smuzhiyun __futex_atomic_op("xor %0, %1, %3", ret, oldval, tmp, uaddr,
90*4882a593Smuzhiyun oparg);
91*4882a593Smuzhiyun break;
92*4882a593Smuzhiyun default:
93*4882a593Smuzhiyun ret = -ENOSYS;
94*4882a593Smuzhiyun }
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun if (!ret)
97*4882a593Smuzhiyun *oval = oldval;
98*4882a593Smuzhiyun
99*4882a593Smuzhiyun return ret;
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun #endif /* __NDS32_FUTEX_H__ */
102