/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 1996, 1999, 2000, 2001, 2003 by Ralf Baechle * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc. */ #ifndef _ASM_UNALIGNED_H #define _ASM_UNALIGNED_H #include /* * get_unaligned - get value from possibly mis-aligned location * @ptr: pointer to value * * This macro should be used for accessing values larger in size than * single bytes at locations that are expected to be improperly aligned, * e.g. retrieving a u16 value from a location not u16-aligned. * * Note that unaligned accesses can be very expensive on some architectures. */ #define get_unaligned(ptr) \ ((__typeof__(*(ptr)))__get_unaligned((ptr), sizeof(*(ptr)))) /* * put_unaligned - put value to a possibly mis-aligned location * @val: value to place * @ptr: pointer to location * * This macro should be used for placing values larger in size than * single bytes at locations that are expected to be improperly aligned, * e.g. writing a u16 value to a location not u16-aligned. * * Note that unaligned accesses can be very expensive on some architectures. */ #define put_unaligned(x,ptr) \ __put_unaligned((__u64)(x), (ptr), sizeof(*(ptr))) /* * This is a silly but good way to make sure that * the get/put functions are indeed always optimized, * and that we use the correct sizes. */ extern void bad_unaligned_access_length(void); /* * EGCS 1.1 knows about arbitrary unaligned loads. Define some * packed structures to talk about such things with. */ 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 * r11) { const struct __una_u64 *ptr = (const struct __una_u64 *) r11; return ptr->x; } static inline __u32 __uldl(const __u32 * r11) { const struct __una_u32 *ptr = (const struct __una_u32 *) r11; return ptr->x; } static inline __u16 __uldw(const __u16 * r11) { const struct __una_u16 *ptr = (const struct __una_u16 *) r11; return ptr->x; } /* * Elemental unaligned stores */ static inline void __ustq(__u64 r5, __u64 * r11) { struct __una_u64 *ptr = (struct __una_u64 *) r11; ptr->x = r5; } static inline void __ustl(__u32 r5, __u32 * r11) { struct __una_u32 *ptr = (struct __una_u32 *) r11; ptr->x = r5; } static inline void __ustw(__u16 r5, __u16 * r11) { struct __una_u16 *ptr = (struct __una_u16 *) r11; ptr->x = r5; } static inline __u64 __get_unaligned(const void *ptr, size_t size) { __u64 val; switch (size) { case 1: val = *(const __u8 *)ptr; break; case 2: val = __uldw((const __u16 *)ptr); break; case 4: val = __uldl((const __u32 *)ptr); break; case 8: val = __uldq((const __u64 *)ptr); break; default: bad_unaligned_access_length(); } return val; } static inline void __put_unaligned(__u64 val, void *ptr, size_t size) { switch (size) { case 1: *(__u8 *)ptr = (val); break; case 2: __ustw(val, (__u16 *)ptr); break; case 4: __ustl(val, (__u32 *)ptr); break; case 8: __ustq(val, (__u64 *)ptr); break; default: bad_unaligned_access_length(); } } #endif /* _ASM_UNALIGNED_H */