#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 */