Make bpf_endian.h compatible with vmlinux.h. It is a frequent request from users wanting to use bpf_endian.h in their BPF applications using CO-RE and vmlinux.h. To achieve that, re-implement byte swap macros and drop all the header includes. This way it can be used both with linux header includes, as well as with a vmlinux.h. Signed-off-by: Andrii Nakryiko <andriin@xxxxxx> --- tools/lib/bpf/bpf_endian.h | 43 +++++++++++++++++++++++++++++++------- 1 file changed, 35 insertions(+), 8 deletions(-) diff --git a/tools/lib/bpf/bpf_endian.h b/tools/lib/bpf/bpf_endian.h index fbe28008450f..ec9db4feca9f 100644 --- a/tools/lib/bpf/bpf_endian.h +++ b/tools/lib/bpf/bpf_endian.h @@ -2,8 +2,35 @@ #ifndef __BPF_ENDIAN__ #define __BPF_ENDIAN__ -#include <linux/stddef.h> -#include <linux/swab.h> +/* + * Isolate byte #n and put it into byte #m, for __u##b type. + * E.g., moving byte #6 (nnnnnnnn) into byte #1 (mmmmmmmm) for __u64: + * 1) xxxxxxxx nnnnnnnn xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx mmmmmmmm xxxxxxxx + * 2) nnnnnnnn xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx mmmmmmmm xxxxxxxx 00000000 + * 3) 00000000 00000000 00000000 00000000 00000000 00000000 00000000 nnnnnnnn + * 4) 00000000 00000000 00000000 00000000 00000000 00000000 nnnnnnnn 00000000 + */ +#define ___bpf_mvb(x, b, n, m) ((__u##b)(x) << (b-(n+1)*8) >> (b-8) << (m*8)) + +#define ___bpf_swab16(x) ((__u16)( \ + ___bpf_mvb(x, 16, 0, 1) | \ + ___bpf_mvb(x, 16, 1, 0))) + +#define ___bpf_swab32(x) ((__u32)( \ + ___bpf_mvb(x, 32, 0, 3) | \ + ___bpf_mvb(x, 32, 1, 2) | \ + ___bpf_mvb(x, 32, 2, 1) | \ + ___bpf_mvb(x, 32, 3, 0))) + +#define ___bpf_swab64(x) ((__u64)( \ + ___bpf_mvb(x, 64, 0, 7) | \ + ___bpf_mvb(x, 64, 1, 6) | \ + ___bpf_mvb(x, 64, 2, 5) | \ + ___bpf_mvb(x, 64, 3, 4) | \ + ___bpf_mvb(x, 64, 4, 3) | \ + ___bpf_mvb(x, 64, 5, 2) | \ + ___bpf_mvb(x, 64, 6, 1) | \ + ___bpf_mvb(x, 64, 7, 0))) /* LLVM's BPF target selects the endianness of the CPU * it compiles on, or the user specifies (bpfel/bpfeb), @@ -23,16 +50,16 @@ #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) +# define __bpf_constant_ntohs(x) ___bpf_swab16(x) +# define __bpf_constant_htons(x) ___bpf_swab16(x) # define __bpf_ntohl(x) __builtin_bswap32(x) # define __bpf_htonl(x) __builtin_bswap32(x) -# define __bpf_constant_ntohl(x) ___constant_swab32(x) -# define __bpf_constant_htonl(x) ___constant_swab32(x) +# define __bpf_constant_ntohl(x) ___bpf_swab32(x) +# define __bpf_constant_htonl(x) ___bpf_swab32(x) # define __bpf_be64_to_cpu(x) __builtin_bswap64(x) # define __bpf_cpu_to_be64(x) __builtin_bswap64(x) -# define __bpf_constant_be64_to_cpu(x) ___constant_swab64(x) -# define __bpf_constant_cpu_to_be64(x) ___constant_swab64(x) +# define __bpf_constant_be64_to_cpu(x) ___bpf_swab64(x) +# define __bpf_constant_cpu_to_be64(x) ___bpf_swab64(x) #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ # define __bpf_ntohs(x) (x) # define __bpf_htons(x) (x) -- 2.24.1
