the library includes a trivial set of BPF syscall wrappers: int bpf_create_map(int key_size, int value_size, int max_entries); int bpf_update_elem(int fd, void *key, void *value); int bpf_lookup_elem(int fd, void *key, void *value); int bpf_delete_elem(int fd, void *key); int bpf_get_next_key(int fd, void *key, void *next_key); int bpf_prog_load(enum bpf_prog_type prog_type, const struct sock_filter_int *insns, int insn_len, const char *license); bpf_prog_load() stores verifier log into global bpf_log_buf[] array Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxxxx> --- samples/bpf/libbpf.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++ samples/bpf/libbpf.h | 21 ++++++++++++ 2 files changed, 110 insertions(+) create mode 100644 samples/bpf/libbpf.c create mode 100644 samples/bpf/libbpf.h diff --git a/samples/bpf/libbpf.c b/samples/bpf/libbpf.c new file mode 100644 index 000000000000..cae0c734274c --- /dev/null +++ b/samples/bpf/libbpf.c @@ -0,0 +1,89 @@ +/* eBPF mini library */ +#include <stdlib.h> +#include <stdio.h> +#include <linux/unistd.h> +#include <unistd.h> +#include <string.h> +#include <linux/netlink.h> +#include <linux/bpf.h> +#include <errno.h> +#include "libbpf.h" + +int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size, + int max_entries) +{ + union bpf_attr attr = { + .map_type = map_type, + .key_size = key_size, + .value_size = value_size, + .max_entries = max_entries + }; + + return syscall(__NR_bpf, BPF_MAP_CREATE, &attr, sizeof(attr)); +} + +int bpf_update_elem(int fd, void *key, void *value) +{ + union bpf_attr attr = { + .map_fd = fd, + .key = key, + .value = value, + }; + + return syscall(__NR_bpf, BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr)); +} + +int bpf_lookup_elem(int fd, void *key, void *value) +{ + union bpf_attr attr = { + .map_fd = fd, + .key = key, + .value = value, + }; + + return syscall(__NR_bpf, BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr)); +} + +int bpf_delete_elem(int fd, void *key) +{ + union bpf_attr attr = { + .map_fd = fd, + .key = key, + }; + + return syscall(__NR_bpf, BPF_MAP_DELETE_ELEM, &attr, sizeof(attr)); +} + +int bpf_get_next_key(int fd, void *key, void *next_key) +{ + union bpf_attr attr = { + .map_fd = fd, + .key = key, + .next_key = next_key, + }; + + return syscall(__NR_bpf, BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr)); +} + +#define ROUND_UP(x, n) (((x) + (n) - 1u) & ~((n) - 1u)) + +char bpf_log_buf[LOG_BUF_SIZE]; + +int bpf_prog_load(enum bpf_prog_type prog_type, + const struct bpf_insn *insns, int prog_len, + const char *license) +{ + union bpf_attr attr = { + .prog_type = prog_type, + .insns = insns, + .insn_cnt = prog_len / sizeof(struct bpf_insn), + .license = license, + .log_buf = bpf_log_buf, + .log_size = LOG_BUF_SIZE, + .log_level = 1, + }; + + bpf_log_buf[0] = 0; + + return syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr)); +} diff --git a/samples/bpf/libbpf.h b/samples/bpf/libbpf.h new file mode 100644 index 000000000000..b19e39794291 --- /dev/null +++ b/samples/bpf/libbpf.h @@ -0,0 +1,21 @@ +/* eBPF mini library */ +#ifndef __LIBBPF_H +#define __LIBBPF_H + +struct bpf_insn; + +int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size, + int max_entries); +int bpf_update_elem(int fd, void *key, void *value); +int bpf_lookup_elem(int fd, void *key, void *value); +int bpf_delete_elem(int fd, void *key); +int bpf_get_next_key(int fd, void *key, void *next_key); + +int bpf_prog_load(enum bpf_prog_type prog_type, + const struct bpf_insn *insns, int insn_len, + const char *license); + +#define LOG_BUF_SIZE 8192 +extern char bpf_log_buf[LOG_BUF_SIZE]; + +#endif -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html