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-rw-r--r--kernel/tools/lib/bpf/bpf.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/kernel/tools/lib/bpf/bpf.c b/kernel/tools/lib/bpf/bpf.c
new file mode 100644
index 000000000..a6331050a
--- /dev/null
+++ b/kernel/tools/lib/bpf/bpf.c
@@ -0,0 +1,85 @@
+/*
+ * common eBPF ELF operations.
+ *
+ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+
+#include <stdlib.h>
+#include <memory.h>
+#include <unistd.h>
+#include <asm/unistd.h>
+#include <linux/bpf.h>
+#include "bpf.h"
+
+/*
+ * When building perf, unistd.h is override. Define __NR_bpf is
+ * required to be defined.
+ */
+#ifndef __NR_bpf
+# if defined(__i386__)
+# define __NR_bpf 357
+# elif defined(__x86_64__)
+# define __NR_bpf 321
+# elif defined(__aarch64__)
+# define __NR_bpf 280
+# else
+# error __NR_bpf not defined. libbpf does not support your arch.
+# endif
+#endif
+
+static __u64 ptr_to_u64(void *ptr)
+{
+ return (__u64) (unsigned long) ptr;
+}
+
+static int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
+ unsigned int size)
+{
+ return syscall(__NR_bpf, cmd, attr, size);
+}
+
+int bpf_create_map(enum bpf_map_type map_type, int key_size,
+ int value_size, int max_entries)
+{
+ union bpf_attr attr;
+
+ memset(&attr, '\0', sizeof(attr));
+
+ attr.map_type = map_type;
+ attr.key_size = key_size;
+ attr.value_size = value_size;
+ attr.max_entries = max_entries;
+
+ return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
+}
+
+int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
+ size_t insns_cnt, char *license,
+ u32 kern_version, char *log_buf, size_t log_buf_sz)
+{
+ int fd;
+ union bpf_attr attr;
+
+ bzero(&attr, sizeof(attr));
+ attr.prog_type = type;
+ attr.insn_cnt = (__u32)insns_cnt;
+ attr.insns = ptr_to_u64(insns);
+ attr.license = ptr_to_u64(license);
+ attr.log_buf = ptr_to_u64(NULL);
+ attr.log_size = 0;
+ attr.log_level = 0;
+ attr.kern_version = kern_version;
+
+ fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
+ if (fd >= 0 || !log_buf || !log_buf_sz)
+ return fd;
+
+ /* Try again with log */
+ attr.log_buf = ptr_to_u64(log_buf);
+ attr.log_size = log_buf_sz;
+ attr.log_level = 1;
+ log_buf[0] = 0;
+ return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
+}