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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_CMPXCHG_H
3#define __ASM_SH_CMPXCHG_H
4
5/*
6 * Atomic operations that C can't guarantee us. Useful for
7 * resource counting etc..
8 */
9
10#include <linux/compiler.h>
11#include <linux/types.h>
12#include <linux/cmpxchg-emu.h>
13
14#if defined(CONFIG_GUSA_RB)
15#include <asm/cmpxchg-grb.h>
16#elif defined(CONFIG_CPU_SH4A)
17#include <asm/cmpxchg-llsc.h>
18#elif defined(CONFIG_CPU_J2) && defined(CONFIG_SMP)
19#include <asm/cmpxchg-cas.h>
20#else
21#include <asm/cmpxchg-irq.h>
22#endif
23
24extern void __xchg_called_with_bad_pointer(void);
25
26#define __arch_xchg(ptr, x, size) \
27({ \
28 unsigned long __xchg__res; \
29 volatile void *__xchg_ptr = (ptr); \
30 switch (size) { \
31 case 4: \
32 __xchg__res = xchg_u32(__xchg_ptr, x); \
33 break; \
34 case 2: \
35 __xchg__res = xchg_u16(__xchg_ptr, x); \
36 break; \
37 case 1: \
38 __xchg__res = xchg_u8(__xchg_ptr, x); \
39 break; \
40 default: \
41 __xchg_called_with_bad_pointer(); \
42 __xchg__res = x; \
43 break; \
44 } \
45 \
46 __xchg__res; \
47})
48
49#define arch_xchg(ptr,x) \
50 ((__typeof__(*(ptr)))__arch_xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))
51
52/* This function doesn't exist, so you'll get a linker error
53 * if something tries to do an invalid cmpxchg(). */
54extern void __cmpxchg_called_with_bad_pointer(void);
55
56static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
57 unsigned long new, int size)
58{
59 switch (size) {
60 case 1:
61 return cmpxchg_emu_u8(ptr, old, new);
62 case 4:
63 return __cmpxchg_u32(ptr, old, new);
64 }
65 __cmpxchg_called_with_bad_pointer();
66 return old;
67}
68
69#define arch_cmpxchg(ptr,o,n) \
70 ({ \
71 __typeof__(*(ptr)) _o_ = (o); \
72 __typeof__(*(ptr)) _n_ = (n); \
73 (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
74 (unsigned long)_n_, sizeof(*(ptr))); \
75 })
76
77#include <asm-generic/cmpxchg-local.h>
78
79#define arch_cmpxchg_local(ptr, o, n) ({ \
80 (__typeof__(*ptr))__generic_cmpxchg_local((ptr), \
81 (unsigned long)(o), \
82 (unsigned long)(n), \
83 sizeof(*(ptr))); \
84})
85
86#endif /* __ASM_SH_CMPXCHG_H */