1 #ifndef _ASM_GENERIC_UNALIGNED_H_
2 #define _ASM_GENERIC_UNALIGNED_H_
5 * For the benefit of those who are trying to port Linux to another
6 * architecture, here are some C-language equivalents.
8 * This is based almost entirely upon Richard Henderson's
9 * asm-alpha/unaligned.h implementation. Some comments were
10 * taken from David Mosberger's asm-ia64/unaligned.h header.
13 #include <linux/types.h>
16 * The main single-value unaligned transfer routines.
18 #define get_unaligned(ptr) \
19 __get_unaligned((ptr), sizeof(*(ptr)))
20 #define put_unaligned(x,ptr) \
21 ((void)sizeof(*(ptr)=(x)),\
22 __put_unaligned((__force __u64)(x), (ptr), sizeof(*(ptr))))
25 * This function doesn't actually exist. The idea is that when
26 * someone uses the macros below with an unsupported size (datatype),
27 * the linker will alert us to the problem via an unresolved reference
30 extern void bad_unaligned_access_length(void) __attribute__((noreturn
));
32 struct __una_u64
{ __u64 x
__attribute__((packed
)); };
33 struct __una_u32
{ __u32 x
__attribute__((packed
)); };
34 struct __una_u16
{ __u16 x
__attribute__((packed
)); };
37 * Elemental unaligned loads
40 static inline __u64
__uldq(const __u64
*addr
)
42 const struct __una_u64
*ptr
= (const struct __una_u64
*) addr
;
46 static inline __u32
__uldl(const __u32
*addr
)
48 const struct __una_u32
*ptr
= (const struct __una_u32
*) addr
;
52 static inline __u16
__uldw(const __u16
*addr
)
54 const struct __una_u16
*ptr
= (const struct __una_u16
*) addr
;
59 * Elemental unaligned stores
62 static inline void __ustq(__u64 val
, __u64
*addr
)
64 struct __una_u64
*ptr
= (struct __una_u64
*) addr
;
68 static inline void __ustl(__u32 val
, __u32
*addr
)
70 struct __una_u32
*ptr
= (struct __una_u32
*) addr
;
74 static inline void __ustw(__u16 val
, __u16
*addr
)
76 struct __una_u16
*ptr
= (struct __una_u16
*) addr
;
80 #define __get_unaligned(ptr, size) ({ \
81 const void *__gu_p = ptr; \
85 __val = *(const __u8 *)__gu_p; \
88 __val = __uldw(__gu_p); \
91 __val = __uldl(__gu_p); \
94 __val = __uldq(__gu_p); \
97 bad_unaligned_access_length(); \
99 (__force __typeof__(*(ptr)))__val; \
102 #define __put_unaligned(val, ptr, size) \
104 void *__gu_p = ptr; \
107 *(__u8 *)__gu_p = (__force __u8)val; \
110 __ustw((__force __u16)val, __gu_p); \
113 __ustl((__force __u32)val, __gu_p); \
116 __ustq(val, __gu_p); \
119 bad_unaligned_access_length(); \
124 #endif /* _ASM_GENERIC_UNALIGNED_H */