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#ifndef _ASM_GENERIC_UNALIGNED_H_
#define _ASM_GENERIC_UNALIGNED_H_
/*
* For the benefit of those who are trying to port Linux to another
* architecture, here are some C-language equivalents.
*
* This is based almost entirely upon Richard Henderson's
* asm-alpha/unaligned.h implementation. Some comments were
* taken from David Mosberger's asm-ia64/unaligned.h header.
*/
#include <linux/types.h>
/*
* The main single-value unaligned transfer routines.
*/
#define get_unaligned(ptr) \
((__typeof__(*(ptr)))__get_unaligned((ptr), sizeof(*(ptr))))
#define put_unaligned(x,ptr) \
__put_unaligned((unsigned long)(x), (ptr), sizeof(*(ptr)))
/*
* This function doesn't actually exist. The idea is that when
* someone uses the macros below with an unsupported size (datatype),
* the linker will alert us to the problem via an unresolved reference
* error.
*/
extern void bad_unaligned_access_length(void) __attribute__((noreturn));
struct __una_u64 { __u64 x __attribute__((packed)); };
struct __una_u32 { __u32 x __attribute__((packed)); };
struct __una_u16 { __u16 x __attribute__((packed)); };
/*
* Elemental unaligned loads
*/
static inline unsigned long __uldq(const __u64 *addr)
{
const struct __una_u64 *ptr = (const struct __una_u64 *) addr;
return ptr->x;
}
static inline unsigned long __uldl(const __u32 *addr)
{
const struct __una_u32 *ptr = (const struct __una_u32 *) addr;
return ptr->x;
}
static inline unsigned long __uldw(const __u16 *addr)
{
const struct __una_u16 *ptr = (const struct __una_u16 *) addr;
return ptr->x;
}
/*
* Elemental unaligned stores
*/
static inline void __ustq(__u64 val, __u64 *addr)
{
struct __una_u64 *ptr = (struct __una_u64 *) addr;
ptr->x = val;
}
static inline void __ustl(__u32 val, __u32 *addr)
{
struct __una_u32 *ptr = (struct __una_u32 *) addr;
ptr->x = val;
}
static inline void __ustw(__u16 val, __u16 *addr)
{
struct __una_u16 *ptr = (struct __una_u16 *) addr;
ptr->x = val;
}
#define __get_unaligned(ptr, size) ({ \
const void *__gu_p = ptr; \
unsigned long val; \
switch (size) { \
case 1: \
val = *(const __u8 *)__gu_p; \
break; \
case 2: \
val = __uldw(__gu_p); \
break; \
case 4: \
val = __uldl(__gu_p); \
break; \
case 8: \
val = __uldq(__gu_p); \
break; \
default: \
bad_unaligned_access_length(); \
}; \
val; \
})
#define __put_unaligned(val, ptr, size) \
do { \
void *__gu_p = ptr; \
switch (size) { \
case 1: \
*(__u8 *)__gu_p = val; \
break; \
case 2: \
__ustw(val, __gu_p); \
break; \
case 4: \
__ustl(val, __gu_p); \
break; \
case 8: \
__ustq(val, __gu_p); \
break; \
default: \
bad_unaligned_access_length(); \
}; \
} while(0)
#endif /* _ASM_GENERIC_UNALIGNED_H */
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