Merge branch 'docs' of git://git.lwn.net/linux-2.6
[linux-2.6] / include / linux / unaligned / generic.h
1 #ifndef _LINUX_UNALIGNED_GENERIC_H
2 #define _LINUX_UNALIGNED_GENERIC_H
3
4 /*
5  * Cause a link-time error if we try an unaligned access other than
6  * 1,2,4 or 8 bytes long
7  */
8 extern void __bad_unaligned_access_size(void);
9
10 #define __get_unaligned_le(ptr) ((__force typeof(*(ptr)))({                     \
11         __builtin_choose_expr(sizeof(*(ptr)) == 1, *(ptr),                      \
12         __builtin_choose_expr(sizeof(*(ptr)) == 2, get_unaligned_le16((ptr)),   \
13         __builtin_choose_expr(sizeof(*(ptr)) == 4, get_unaligned_le32((ptr)),   \
14         __builtin_choose_expr(sizeof(*(ptr)) == 8, get_unaligned_le64((ptr)),   \
15         __bad_unaligned_access_size()))));                                      \
16         }))
17
18 #define __get_unaligned_be(ptr) ((__force typeof(*(ptr)))({                     \
19         __builtin_choose_expr(sizeof(*(ptr)) == 1, *(ptr),                      \
20         __builtin_choose_expr(sizeof(*(ptr)) == 2, get_unaligned_be16((ptr)),   \
21         __builtin_choose_expr(sizeof(*(ptr)) == 4, get_unaligned_be32((ptr)),   \
22         __builtin_choose_expr(sizeof(*(ptr)) == 8, get_unaligned_be64((ptr)),   \
23         __bad_unaligned_access_size()))));                                      \
24         }))
25
26 #define __put_unaligned_le(val, ptr) ({                                 \
27         void *__gu_p = (ptr);                                           \
28         switch (sizeof(*(ptr))) {                                       \
29         case 1:                                                         \
30                 *(u8 *)__gu_p = (__force u8)(val);                      \
31                 break;                                                  \
32         case 2:                                                         \
33                 put_unaligned_le16((__force u16)(val), __gu_p);         \
34                 break;                                                  \
35         case 4:                                                         \
36                 put_unaligned_le32((__force u32)(val), __gu_p);         \
37                 break;                                                  \
38         case 8:                                                         \
39                 put_unaligned_le64((__force u64)(val), __gu_p);         \
40                 break;                                                  \
41         default:                                                        \
42                 __bad_unaligned_access_size();                          \
43                 break;                                                  \
44         }                                                               \
45         (void)0; })
46
47 #define __put_unaligned_be(val, ptr) ({                                 \
48         void *__gu_p = (ptr);                                           \
49         switch (sizeof(*(ptr))) {                                       \
50         case 1:                                                         \
51                 *(u8 *)__gu_p = (__force u8)(val);                      \
52                 break;                                                  \
53         case 2:                                                         \
54                 put_unaligned_be16((__force u16)(val), __gu_p);         \
55                 break;                                                  \
56         case 4:                                                         \
57                 put_unaligned_be32((__force u32)(val), __gu_p);         \
58                 break;                                                  \
59         case 8:                                                         \
60                 put_unaligned_be64((__force u64)(val), __gu_p);         \
61                 break;                                                  \
62         default:                                                        \
63                 __bad_unaligned_access_size();                          \
64                 break;                                                  \
65         }                                                               \
66         (void)0; })
67
68 #endif /* _LINUX_UNALIGNED_GENERIC_H */