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