1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __BPF_ENDIAN__ 3 #define __BPF_ENDIAN__ 4 5 #include <linux/swab.h> 6 7 /* LLVM's BPF target selects the endianness of the CPU 8 * it compiles on, or the user specifies (bpfel/bpfeb), 9 * respectively. The used __BYTE_ORDER__ is defined by 10 * the compiler, we cannot rely on __BYTE_ORDER from 11 * libc headers, since it doesn't reflect the actual 12 * requested byte order. 13 * 14 * Note, LLVM's BPF target has different __builtin_bswapX() 15 * semantics. It does map to BPF_ALU | BPF_END | BPF_TO_BE 16 * in bpfel and bpfeb case, which means below, that we map 17 * to cpu_to_be16(). We could use it unconditionally in BPF 18 * case, but better not rely on it, so that this header here 19 * can be used from application and BPF program side, which 20 * use different targets. 21 */ 22 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 23 # define __bpf_ntohs(x) __builtin_bswap16(x) 24 # define __bpf_htons(x) __builtin_bswap16(x) 25 # define __bpf_constant_ntohs(x) ___constant_swab16(x) 26 # define __bpf_constant_htons(x) ___constant_swab16(x) 27 # define __bpf_ntohl(x) __builtin_bswap32(x) 28 # define __bpf_htonl(x) __builtin_bswap32(x) 29 # define __bpf_constant_ntohl(x) ___constant_swab32(x) 30 # define __bpf_constant_htonl(x) ___constant_swab32(x) 31 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ 32 # define __bpf_ntohs(x) (x) 33 # define __bpf_htons(x) (x) 34 # define __bpf_constant_ntohs(x) (x) 35 # define __bpf_constant_htons(x) (x) 36 # define __bpf_ntohl(x) (x) 37 # define __bpf_htonl(x) (x) 38 # define __bpf_constant_ntohl(x) (x) 39 # define __bpf_constant_htonl(x) (x) 40 #else 41 # error "Fix your compiler's __BYTE_ORDER__?!" 42 #endif 43 44 #define bpf_htons(x) \ 45 (__builtin_constant_p(x) ? \ 46 __bpf_constant_htons(x) : __bpf_htons(x)) 47 #define bpf_ntohs(x) \ 48 (__builtin_constant_p(x) ? \ 49 __bpf_constant_ntohs(x) : __bpf_ntohs(x)) 50 #define bpf_htonl(x) \ 51 (__builtin_constant_p(x) ? \ 52 __bpf_constant_htonl(x) : __bpf_htonl(x)) 53 #define bpf_ntohl(x) \ 54 (__builtin_constant_p(x) ? \ 55 __bpf_constant_ntohl(x) : __bpf_ntohl(x)) 56 57 #endif /* __BPF_ENDIAN__ */ 58
