diff options
Diffstat (limited to 'tools/testing/selftests/bpf/bpf_endian.h')
| -rw-r--r-- | tools/testing/selftests/bpf/bpf_endian.h | 41 |
1 files changed, 30 insertions, 11 deletions
diff --git a/tools/testing/selftests/bpf/bpf_endian.h b/tools/testing/selftests/bpf/bpf_endian.h index 19d0604f8694..487cbfb89beb 100644 --- a/tools/testing/selftests/bpf/bpf_endian.h +++ b/tools/testing/selftests/bpf/bpf_endian.h @@ -1,23 +1,42 @@ #ifndef __BPF_ENDIAN__ #define __BPF_ENDIAN__ -#include <asm/byteorder.h> +#include <linux/swab.h> -#if __BYTE_ORDER == __LITTLE_ENDIAN -# define __bpf_ntohs(x) __builtin_bswap16(x) -# define __bpf_htons(x) __builtin_bswap16(x) -#elif __BYTE_ORDER == __BIG_ENDIAN -# define __bpf_ntohs(x) (x) -# define __bpf_htons(x) (x) +/* LLVM's BPF target selects the endianness of the CPU + * it compiles on, or the user specifies (bpfel/bpfeb), + * respectively. The used __BYTE_ORDER__ is defined by + * the compiler, we cannot rely on __BYTE_ORDER from + * libc headers, since it doesn't reflect the actual + * requested byte order. + * + * Note, LLVM's BPF target has different __builtin_bswapX() + * semantics. It does map to BPF_ALU | BPF_END | BPF_TO_BE + * in bpfel and bpfeb case, which means below, that we map + * to cpu_to_be16(). We could use it unconditionally in BPF + * case, but better not rely on it, so that this header here + * can be used from application and BPF program side, which + * use different targets. + */ +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +# define __bpf_ntohs(x) __builtin_bswap16(x) +# define __bpf_htons(x) __builtin_bswap16(x) +# define __bpf_constant_ntohs(x) ___constant_swab16(x) +# define __bpf_constant_htons(x) ___constant_swab16(x) +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ +# define __bpf_ntohs(x) (x) +# define __bpf_htons(x) (x) +# define __bpf_constant_ntohs(x) (x) +# define __bpf_constant_htons(x) (x) #else -# error "Fix your __BYTE_ORDER?!" +# error "Fix your compiler's __BYTE_ORDER__?!" #endif #define bpf_htons(x) \ (__builtin_constant_p(x) ? \ - __constant_htons(x) : __bpf_htons(x)) + __bpf_constant_htons(x) : __bpf_htons(x)) #define bpf_ntohs(x) \ (__builtin_constant_p(x) ? \ - __constant_ntohs(x) : __bpf_ntohs(x)) + __bpf_constant_ntohs(x) : __bpf_ntohs(x)) -#endif +#endif /* __BPF_ENDIAN__ */ |