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