707ced0d71
If the 'ptr' is a const, this code cause "assignment of read-only variable" error on gcc 4.x. Use __u64 instead of __typeof__(*(ptr)) for temporary variable to get rid of errors on gcc 4.x. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
123 lines
2.7 KiB
C
123 lines
2.7 KiB
C
#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) \
|
|
__get_unaligned((ptr), sizeof(*(ptr)))
|
|
#define put_unaligned(x,ptr) \
|
|
__put_unaligned((__u64)(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 __u64 __uldq(const __u64 *addr)
|
|
{
|
|
const struct __una_u64 *ptr = (const struct __una_u64 *) addr;
|
|
return ptr->x;
|
|
}
|
|
|
|
static inline __u32 __uldl(const __u32 *addr)
|
|
{
|
|
const struct __una_u32 *ptr = (const struct __una_u32 *) addr;
|
|
return ptr->x;
|
|
}
|
|
|
|
static inline __u16 __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; \
|
|
__u64 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(); \
|
|
}; \
|
|
(__typeof__(*(ptr)))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 */
|