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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /tools/lib/bpf/bpf_endian.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/lib/bpf/bpf_endian.h')
-rw-r--r--tools/lib/bpf/bpf_endian.h99
1 files changed, 99 insertions, 0 deletions
diff --git a/tools/lib/bpf/bpf_endian.h b/tools/lib/bpf/bpf_endian.h
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+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#ifndef __BPF_ENDIAN__
+#define __BPF_ENDIAN__
+
+/*
+ * 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),
+ * 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) ___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) ___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) ___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)
+# define __bpf_constant_ntohs(x) (x)
+# define __bpf_constant_htons(x) (x)
+# define __bpf_ntohl(x) (x)
+# define __bpf_htonl(x) (x)
+# define __bpf_constant_ntohl(x) (x)
+# define __bpf_constant_htonl(x) (x)
+# define __bpf_be64_to_cpu(x) (x)
+# define __bpf_cpu_to_be64(x) (x)
+# define __bpf_constant_be64_to_cpu(x) (x)
+# define __bpf_constant_cpu_to_be64(x) (x)
+#else
+# error "Fix your compiler's __BYTE_ORDER__?!"
+#endif
+
+#define bpf_htons(x) \
+ (__builtin_constant_p(x) ? \
+ __bpf_constant_htons(x) : __bpf_htons(x))
+#define bpf_ntohs(x) \
+ (__builtin_constant_p(x) ? \
+ __bpf_constant_ntohs(x) : __bpf_ntohs(x))
+#define bpf_htonl(x) \
+ (__builtin_constant_p(x) ? \
+ __bpf_constant_htonl(x) : __bpf_htonl(x))
+#define bpf_ntohl(x) \
+ (__builtin_constant_p(x) ? \
+ __bpf_constant_ntohl(x) : __bpf_ntohl(x))
+#define bpf_cpu_to_be64(x) \
+ (__builtin_constant_p(x) ? \
+ __bpf_constant_cpu_to_be64(x) : __bpf_cpu_to_be64(x))
+#define bpf_be64_to_cpu(x) \
+ (__builtin_constant_p(x) ? \
+ __bpf_constant_be64_to_cpu(x) : __bpf_be64_to_cpu(x))
+
+#endif /* __BPF_ENDIAN__ */