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 ((__typeof__(*(ptr)))__get_unaligned((ptr), sizeof(*(ptr))))
20 #define put_unaligned(x,ptr) \
21 __put_unaligned((unsigned long)(x), (ptr), sizeof(*(ptr)))
24 * This function doesn't actually exist. The idea is that when
25 * someone uses the macros below with an unsupported size (datatype),
26 * the linker will alert us to the problem via an unresolved reference
29 extern void bad_unaligned_access_length(void) __attribute__((noreturn
));
31 struct __una_u64
{ __u64 x
__attribute__((packed
)); };
32 struct __una_u32
{ __u32 x
__attribute__((packed
)); };
33 struct __una_u16
{ __u16 x
__attribute__((packed
)); };
36 * Elemental unaligned loads
39 static inline unsigned long __uldq(const __u64
*addr
)
41 const struct __una_u64
*ptr
= (const struct __una_u64
*) addr
;
45 static inline unsigned long __uldl(const __u32
*addr
)
47 const struct __una_u32
*ptr
= (const struct __una_u32
*) addr
;
51 static inline unsigned long __uldw(const __u16
*addr
)
53 const struct __una_u16
*ptr
= (const struct __una_u16
*) addr
;
58 * Elemental unaligned stores
61 static inline void __ustq(__u64 val
, __u64
*addr
)
63 struct __una_u64
*ptr
= (struct __una_u64
*) addr
;
67 static inline void __ustl(__u32 val
, __u32
*addr
)
69 struct __una_u32
*ptr
= (struct __una_u32
*) addr
;
73 static inline void __ustw(__u16 val
, __u16
*addr
)
75 struct __una_u16
*ptr
= (struct __una_u16
*) addr
;
79 static inline unsigned long __get_unaligned(const void *ptr
, size_t size
)
84 val
= *(const __u8
*)ptr
;
87 val
= __uldw((const __u16
*)ptr
);
90 val
= __uldl((const __u32
*)ptr
);
93 val
= __uldq((const __u64
*)ptr
);
96 bad_unaligned_access_length();
101 static inline void __put_unaligned(unsigned long val
, void *ptr
, size_t size
)
108 __ustw(val
, (__u16
*)ptr
);
111 __ustl(val
, (__u32
*)ptr
);
114 __ustq(val
, (__u64
*)ptr
);
117 bad_unaligned_access_length();
121 #endif /* _ASM_GENERIC_UNALIGNED_H */