diff --git a/include/linux/types.h b/include/linux/types.h index 76c6b670a..14f831541 100644 --- a/include/linux/types.h +++ b/include/linux/types.h @@ -142,6 +142,19 @@ typedef __u64 __bitwise __be64; typedef __u16 __bitwise __sum16; typedef __u32 __bitwise __wsum; +/* + * aligned_u64 should be used in defining kernel<->userspace ABIs to avoid + * common 32/64-bit compat problems. + * 64-bit values align to 4-byte boundaries on x86_32 (and possibly other + * architectures) and to 8-byte boundaries on 64-bit architectures. The new + * aligned_64 type enforces 8-byte alignment so that structs containing + * aligned_64 values have the same alignment on 32-bit and 64-bit architectures. + * No conversions are necessary between 32-bit user-space and a 64-bit kernel. + */ +#define __aligned_u64 __u64 __attribute__((aligned(8))) +#define __aligned_be64 __be64 __attribute__((aligned(8))) +#define __aligned_le64 __le64 __attribute__((aligned(8))) + #ifdef CONFIG_PHYS_ADDR_T_64BIT typedef u64 phys_addr_t; typedef u64 phys_size_t;