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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_SH_FUTEX_H
3#define __ASM_SH_FUTEX_H
4
5#ifdef __KERNEL__
6
7#include <linux/futex.h>
8#include <linux/uaccess.h>
9#include <asm/errno.h>
10
11#if !defined(CONFIG_SMP)
12#include <asm/futex-irq.h>
13#elif defined(CONFIG_CPU_J2)
14#include <asm/futex-cas.h>
15#elif defined(CONFIG_CPU_SH4A)
16#include <asm/futex-llsc.h>
17#else
18#error SMP not supported on this configuration.
19#endif
20
21static inline int
22futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
23 u32 oldval, u32 newval)
24{
25 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
26 return -EFAULT;
27
28 return atomic_futex_op_cmpxchg_inatomic(uval, uaddr, oldval, newval);
29}
30
31static inline int arch_futex_atomic_op_inuser(int op, u32 oparg, int *oval,
32 u32 __user *uaddr)
33{
34 u32 oldval, newval, prev;
35 int ret;
36
37 pagefault_disable();
38
39 do {
40 if (op == FUTEX_OP_SET)
41 ret = oldval = 0;
42 else
43 ret = get_user(oldval, uaddr);
44
45 if (ret) break;
46
47 switch (op) {
48 case FUTEX_OP_SET:
49 newval = oparg;
50 break;
51 case FUTEX_OP_ADD:
52 newval = oldval + oparg;
53 break;
54 case FUTEX_OP_OR:
55 newval = oldval | oparg;
56 break;
57 case FUTEX_OP_ANDN:
58 newval = oldval & ~oparg;
59 break;
60 case FUTEX_OP_XOR:
61 newval = oldval ^ oparg;
62 break;
63 default:
64 ret = -ENOSYS;
65 break;
66 }
67
68 if (ret) break;
69
70 ret = futex_atomic_cmpxchg_inatomic(&prev, uaddr, oldval, newval);
71 } while (!ret && prev != oldval);
72
73 pagefault_enable();
74
75 if (!ret)
76 *oval = oldval;
77
78 return ret;
79}
80
81#endif /* __KERNEL__ */
82#endif /* __ASM_SH_FUTEX_H */