forked from Minki/linux
samples: bpf: Remove bpf_load loader completely
Numerous refactoring that rewrites BPF programs written with bpf_load to use the libbpf loader was finally completed, resulting in BPF programs using bpf_load within the kernel being completely no longer present. This commit removes bpf_load, an outdated bpf loader that is difficult to keep up with the latest kernel BPF and causes confusion. Also, this commit removes the unused trace_helper and bpf_load from samples/bpf target objects from Makefile. Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201124090310.24374-8-danieltimlee@gmail.com
This commit is contained in:
Daniel T. Lee
Andrii Nakryiko
parent
0afe0a998c
commit
ceb5dea565
@ -73,7 +73,7 @@ tracex5-objs := tracex5_user.o $(TRACE_HELPERS)
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tracex6-objs := tracex6_user.o
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tracex7-objs := tracex7_user.o
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test_probe_write_user-objs := test_probe_write_user_user.o
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trace_output-objs := trace_output_user.o $(TRACE_HELPERS)
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trace_output-objs := trace_output_user.o
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lathist-objs := lathist_user.o
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offwaketime-objs := offwaketime_user.o $(TRACE_HELPERS)
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spintest-objs := spintest_user.o $(TRACE_HELPERS)
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@ -91,8 +91,8 @@ test_current_task_under_cgroup-objs := $(CGROUP_HELPERS) \
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test_current_task_under_cgroup_user.o
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trace_event-objs := trace_event_user.o $(TRACE_HELPERS)
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sampleip-objs := sampleip_user.o $(TRACE_HELPERS)
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tc_l2_redirect-objs := bpf_load.o tc_l2_redirect_user.o
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lwt_len_hist-objs := bpf_load.o lwt_len_hist_user.o
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tc_l2_redirect-objs := tc_l2_redirect_user.o
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lwt_len_hist-objs := lwt_len_hist_user.o
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xdp_tx_iptunnel-objs := xdp_tx_iptunnel_user.o
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test_map_in_map-objs := test_map_in_map_user.o
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per_socket_stats_example-objs := cookie_uid_helper_example.o
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@ -108,7 +108,7 @@ xdpsock-objs := xdpsock_user.o
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xsk_fwd-objs := xsk_fwd.o
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xdp_fwd-objs := xdp_fwd_user.o
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task_fd_query-objs := task_fd_query_user.o $(TRACE_HELPERS)
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xdp_sample_pkts-objs := xdp_sample_pkts_user.o $(TRACE_HELPERS)
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xdp_sample_pkts-objs := xdp_sample_pkts_user.o
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ibumad-objs := ibumad_user.o
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hbm-objs := hbm.o $(CGROUP_HELPERS)
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@ -197,8 +197,6 @@ TPROGS_CFLAGS += --sysroot=$(SYSROOT)
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TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
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endif
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TPROGCFLAGS_bpf_load.o += -Wno-unused-variable
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TPROGS_LDLIBS += $(LIBBPF) -lelf -lz
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TPROGLDLIBS_tracex4 += -lrt
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TPROGLDLIBS_trace_output += -lrt
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@ -1,667 +0,0 @@
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// SPDX-License-Identifier: GPL-2.0
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#include <stdio.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <libelf.h>
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#include <gelf.h>
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#include <errno.h>
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#include <unistd.h>
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#include <string.h>
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#include <stdbool.h>
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#include <stdlib.h>
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#include <linux/bpf.h>
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#include <linux/filter.h>
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#include <linux/perf_event.h>
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#include <linux/netlink.h>
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#include <linux/rtnetlink.h>
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#include <linux/types.h>
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#include <sys/socket.h>
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#include <sys/syscall.h>
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#include <sys/ioctl.h>
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#include <sys/mman.h>
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#include <poll.h>
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#include <ctype.h>
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#include <assert.h>
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#include <bpf/bpf.h>
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#include "bpf_load.h"
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#include "perf-sys.h"
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#define DEBUGFS "/sys/kernel/debug/tracing/"
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static char license[128];
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static int kern_version;
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static bool processed_sec[128];
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char bpf_log_buf[BPF_LOG_BUF_SIZE];
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int map_fd[MAX_MAPS];
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int prog_fd[MAX_PROGS];
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int event_fd[MAX_PROGS];
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int prog_cnt;
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int prog_array_fd = -1;
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struct bpf_map_data map_data[MAX_MAPS];
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int map_data_count;
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static int populate_prog_array(const char *event, int prog_fd)
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{
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int ind = atoi(event), err;
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err = bpf_map_update_elem(prog_array_fd, &ind, &prog_fd, BPF_ANY);
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if (err < 0) {
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printf("failed to store prog_fd in prog_array\n");
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return -1;
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}
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return 0;
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}
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static int write_kprobe_events(const char *val)
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{
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int fd, ret, flags;
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if (val == NULL)
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return -1;
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else if (val[0] == '\0')
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flags = O_WRONLY | O_TRUNC;
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else
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flags = O_WRONLY | O_APPEND;
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fd = open(DEBUGFS "kprobe_events", flags);
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ret = write(fd, val, strlen(val));
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close(fd);
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return ret;
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}
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static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
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{
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bool is_socket = strncmp(event, "socket", 6) == 0;
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bool is_kprobe = strncmp(event, "kprobe/", 7) == 0;
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bool is_kretprobe = strncmp(event, "kretprobe/", 10) == 0;
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bool is_tracepoint = strncmp(event, "tracepoint/", 11) == 0;
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bool is_raw_tracepoint = strncmp(event, "raw_tracepoint/", 15) == 0;
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bool is_xdp = strncmp(event, "xdp", 3) == 0;
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bool is_perf_event = strncmp(event, "perf_event", 10) == 0;
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bool is_cgroup_skb = strncmp(event, "cgroup/skb", 10) == 0;
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bool is_cgroup_sk = strncmp(event, "cgroup/sock", 11) == 0;
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bool is_sockops = strncmp(event, "sockops", 7) == 0;
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bool is_sk_skb = strncmp(event, "sk_skb", 6) == 0;
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bool is_sk_msg = strncmp(event, "sk_msg", 6) == 0;
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size_t insns_cnt = size / sizeof(struct bpf_insn);
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enum bpf_prog_type prog_type;
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char buf[256];
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int fd, efd, err, id;
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struct perf_event_attr attr = {};
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attr.type = PERF_TYPE_TRACEPOINT;
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attr.sample_type = PERF_SAMPLE_RAW;
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attr.sample_period = 1;
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attr.wakeup_events = 1;
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if (is_socket) {
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prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
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} else if (is_kprobe || is_kretprobe) {
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prog_type = BPF_PROG_TYPE_KPROBE;
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} else if (is_tracepoint) {
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prog_type = BPF_PROG_TYPE_TRACEPOINT;
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} else if (is_raw_tracepoint) {
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prog_type = BPF_PROG_TYPE_RAW_TRACEPOINT;
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} else if (is_xdp) {
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prog_type = BPF_PROG_TYPE_XDP;
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} else if (is_perf_event) {
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prog_type = BPF_PROG_TYPE_PERF_EVENT;
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} else if (is_cgroup_skb) {
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prog_type = BPF_PROG_TYPE_CGROUP_SKB;
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} else if (is_cgroup_sk) {
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prog_type = BPF_PROG_TYPE_CGROUP_SOCK;
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} else if (is_sockops) {
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prog_type = BPF_PROG_TYPE_SOCK_OPS;
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} else if (is_sk_skb) {
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prog_type = BPF_PROG_TYPE_SK_SKB;
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} else if (is_sk_msg) {
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prog_type = BPF_PROG_TYPE_SK_MSG;
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} else {
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printf("Unknown event '%s'\n", event);
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return -1;
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}
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if (prog_cnt == MAX_PROGS)
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return -1;
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fd = bpf_load_program(prog_type, prog, insns_cnt, license, kern_version,
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bpf_log_buf, BPF_LOG_BUF_SIZE);
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if (fd < 0) {
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printf("bpf_load_program() err=%d\n%s", errno, bpf_log_buf);
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return -1;
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}
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prog_fd[prog_cnt++] = fd;
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if (is_xdp || is_perf_event || is_cgroup_skb || is_cgroup_sk)
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return 0;
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if (is_socket || is_sockops || is_sk_skb || is_sk_msg) {
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if (is_socket)
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event += 6;
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else
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event += 7;
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if (*event != '/')
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return 0;
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event++;
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if (!isdigit(*event)) {
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printf("invalid prog number\n");
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return -1;
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}
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return populate_prog_array(event, fd);
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}
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if (is_raw_tracepoint) {
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efd = bpf_raw_tracepoint_open(event + 15, fd);
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if (efd < 0) {
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printf("tracepoint %s %s\n", event + 15, strerror(errno));
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return -1;
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}
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event_fd[prog_cnt - 1] = efd;
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return 0;
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}
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if (is_kprobe || is_kretprobe) {
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bool need_normal_check = true;
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const char *event_prefix = "";
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if (is_kprobe)
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event += 7;
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else
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event += 10;
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if (*event == 0) {
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printf("event name cannot be empty\n");
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return -1;
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}
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if (isdigit(*event))
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return populate_prog_array(event, fd);
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#ifdef __x86_64__
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if (strncmp(event, "sys_", 4) == 0) {
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snprintf(buf, sizeof(buf), "%c:__x64_%s __x64_%s",
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is_kprobe ? 'p' : 'r', event, event);
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err = write_kprobe_events(buf);
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if (err >= 0) {
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need_normal_check = false;
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event_prefix = "__x64_";
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}
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}
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#endif
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if (need_normal_check) {
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snprintf(buf, sizeof(buf), "%c:%s %s",
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is_kprobe ? 'p' : 'r', event, event);
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err = write_kprobe_events(buf);
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if (err < 0) {
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printf("failed to create kprobe '%s' error '%s'\n",
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event, strerror(errno));
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return -1;
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}
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}
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strcpy(buf, DEBUGFS);
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strcat(buf, "events/kprobes/");
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strcat(buf, event_prefix);
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strcat(buf, event);
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strcat(buf, "/id");
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} else if (is_tracepoint) {
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event += 11;
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if (*event == 0) {
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printf("event name cannot be empty\n");
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return -1;
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}
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strcpy(buf, DEBUGFS);
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strcat(buf, "events/");
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strcat(buf, event);
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strcat(buf, "/id");
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}
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efd = open(buf, O_RDONLY, 0);
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if (efd < 0) {
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printf("failed to open event %s\n", event);
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return -1;
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}
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err = read(efd, buf, sizeof(buf));
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if (err < 0 || err >= sizeof(buf)) {
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printf("read from '%s' failed '%s'\n", event, strerror(errno));
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return -1;
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}
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close(efd);
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buf[err] = 0;
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id = atoi(buf);
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attr.config = id;
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efd = sys_perf_event_open(&attr, -1/*pid*/, 0/*cpu*/, -1/*group_fd*/, 0);
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if (efd < 0) {
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printf("event %d fd %d err %s\n", id, efd, strerror(errno));
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return -1;
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}
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event_fd[prog_cnt - 1] = efd;
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err = ioctl(efd, PERF_EVENT_IOC_ENABLE, 0);
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if (err < 0) {
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printf("ioctl PERF_EVENT_IOC_ENABLE failed err %s\n",
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strerror(errno));
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return -1;
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}
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err = ioctl(efd, PERF_EVENT_IOC_SET_BPF, fd);
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if (err < 0) {
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printf("ioctl PERF_EVENT_IOC_SET_BPF failed err %s\n",
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strerror(errno));
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return -1;
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}
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return 0;
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}
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static int load_maps(struct bpf_map_data *maps, int nr_maps,
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fixup_map_cb fixup_map)
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{
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int i, numa_node;
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for (i = 0; i < nr_maps; i++) {
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if (fixup_map) {
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fixup_map(&maps[i], i);
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/* Allow userspace to assign map FD prior to creation */
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if (maps[i].fd != -1) {
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map_fd[i] = maps[i].fd;
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continue;
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}
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}
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numa_node = maps[i].def.map_flags & BPF_F_NUMA_NODE ?
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maps[i].def.numa_node : -1;
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if (maps[i].def.type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
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maps[i].def.type == BPF_MAP_TYPE_HASH_OF_MAPS) {
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int inner_map_fd = map_fd[maps[i].def.inner_map_idx];
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map_fd[i] = bpf_create_map_in_map_node(maps[i].def.type,
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maps[i].name,
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maps[i].def.key_size,
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inner_map_fd,
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maps[i].def.max_entries,
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maps[i].def.map_flags,
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numa_node);
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} else {
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map_fd[i] = bpf_create_map_node(maps[i].def.type,
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maps[i].name,
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maps[i].def.key_size,
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maps[i].def.value_size,
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maps[i].def.max_entries,
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maps[i].def.map_flags,
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numa_node);
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}
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if (map_fd[i] < 0) {
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printf("failed to create map %d (%s): %d %s\n",
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i, maps[i].name, errno, strerror(errno));
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return 1;
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}
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maps[i].fd = map_fd[i];
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if (maps[i].def.type == BPF_MAP_TYPE_PROG_ARRAY)
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prog_array_fd = map_fd[i];
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}
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return 0;
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}
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static int get_sec(Elf *elf, int i, GElf_Ehdr *ehdr, char **shname,
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GElf_Shdr *shdr, Elf_Data **data)
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{
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Elf_Scn *scn;
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scn = elf_getscn(elf, i);
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if (!scn)
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return 1;
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if (gelf_getshdr(scn, shdr) != shdr)
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return 2;
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*shname = elf_strptr(elf, ehdr->e_shstrndx, shdr->sh_name);
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if (!*shname || !shdr->sh_size)
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return 3;
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*data = elf_getdata(scn, 0);
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if (!*data || elf_getdata(scn, *data) != NULL)
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return 4;
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return 0;
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}
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static int parse_relo_and_apply(Elf_Data *data, Elf_Data *symbols,
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GElf_Shdr *shdr, struct bpf_insn *insn,
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struct bpf_map_data *maps, int nr_maps)
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{
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int i, nrels;
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nrels = shdr->sh_size / shdr->sh_entsize;
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for (i = 0; i < nrels; i++) {
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GElf_Sym sym;
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GElf_Rel rel;
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unsigned int insn_idx;
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bool match = false;
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int j, map_idx;
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gelf_getrel(data, i, &rel);
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insn_idx = rel.r_offset / sizeof(struct bpf_insn);
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gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym);
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if (insn[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) {
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printf("invalid relo for insn[%d].code 0x%x\n",
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insn_idx, insn[insn_idx].code);
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return 1;
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}
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insn[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;
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/* Match FD relocation against recorded map_data[] offset */
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for (map_idx = 0; map_idx < nr_maps; map_idx++) {
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if (maps[map_idx].elf_offset == sym.st_value) {
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match = true;
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break;
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}
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}
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if (match) {
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insn[insn_idx].imm = maps[map_idx].fd;
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} else {
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printf("invalid relo for insn[%d] no map_data match\n",
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insn_idx);
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return 1;
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}
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}
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return 0;
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}
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static int cmp_symbols(const void *l, const void *r)
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{
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const GElf_Sym *lsym = (const GElf_Sym *)l;
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||||
const GElf_Sym *rsym = (const GElf_Sym *)r;
|
||||
|
||||
if (lsym->st_value < rsym->st_value)
|
||||
return -1;
|
||||
else if (lsym->st_value > rsym->st_value)
|
||||
return 1;
|
||||
else
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int load_elf_maps_section(struct bpf_map_data *maps, int maps_shndx,
|
||||
Elf *elf, Elf_Data *symbols, int strtabidx)
|
||||
{
|
||||
int map_sz_elf, map_sz_copy;
|
||||
bool validate_zero = false;
|
||||
Elf_Data *data_maps;
|
||||
int i, nr_maps;
|
||||
GElf_Sym *sym;
|
||||
Elf_Scn *scn;
|
||||
int copy_sz;
|
||||
|
||||
if (maps_shndx < 0)
|
||||
return -EINVAL;
|
||||
if (!symbols)
|
||||
return -EINVAL;
|
||||
|
||||
/* Get data for maps section via elf index */
|
||||
scn = elf_getscn(elf, maps_shndx);
|
||||
if (scn)
|
||||
data_maps = elf_getdata(scn, NULL);
|
||||
if (!scn || !data_maps) {
|
||||
printf("Failed to get Elf_Data from maps section %d\n",
|
||||
maps_shndx);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* For each map get corrosponding symbol table entry */
|
||||
sym = calloc(MAX_MAPS+1, sizeof(GElf_Sym));
|
||||
for (i = 0, nr_maps = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
|
||||
assert(nr_maps < MAX_MAPS+1);
|
||||
if (!gelf_getsym(symbols, i, &sym[nr_maps]))
|
||||
continue;
|
||||
if (sym[nr_maps].st_shndx != maps_shndx)
|
||||
continue;
|
||||
/* Only increment iif maps section */
|
||||
nr_maps++;
|
||||
}
|
||||
|
||||
/* Align to map_fd[] order, via sort on offset in sym.st_value */
|
||||
qsort(sym, nr_maps, sizeof(GElf_Sym), cmp_symbols);
|
||||
|
||||
/* Keeping compatible with ELF maps section changes
|
||||
* ------------------------------------------------
|
||||
* The program size of struct bpf_load_map_def is known by loader
|
||||
* code, but struct stored in ELF file can be different.
|
||||
*
|
||||
* Unfortunately sym[i].st_size is zero. To calculate the
|
||||
* struct size stored in the ELF file, assume all struct have
|
||||
* the same size, and simply divide with number of map
|
||||
* symbols.
|
||||
*/
|
||||
map_sz_elf = data_maps->d_size / nr_maps;
|
||||
map_sz_copy = sizeof(struct bpf_load_map_def);
|
||||
if (map_sz_elf < map_sz_copy) {
|
||||
/*
|
||||
* Backward compat, loading older ELF file with
|
||||
* smaller struct, keeping remaining bytes zero.
|
||||
*/
|
||||
map_sz_copy = map_sz_elf;
|
||||
} else if (map_sz_elf > map_sz_copy) {
|
||||
/*
|
||||
* Forward compat, loading newer ELF file with larger
|
||||
* struct with unknown features. Assume zero means
|
||||
* feature not used. Thus, validate rest of struct
|
||||
* data is zero.
|
||||
*/
|
||||
validate_zero = true;
|
||||
}
|
||||
|
||||
/* Memcpy relevant part of ELF maps data to loader maps */
|
||||
for (i = 0; i < nr_maps; i++) {
|
||||
struct bpf_load_map_def *def;
|
||||
unsigned char *addr, *end;
|
||||
const char *map_name;
|
||||
size_t offset;
|
||||
|
||||
map_name = elf_strptr(elf, strtabidx, sym[i].st_name);
|
||||
maps[i].name = strdup(map_name);
|
||||
if (!maps[i].name) {
|
||||
printf("strdup(%s): %s(%d)\n", map_name,
|
||||
strerror(errno), errno);
|
||||
free(sym);
|
||||
return -errno;
|
||||
}
|
||||
|
||||
/* Symbol value is offset into ELF maps section data area */
|
||||
offset = sym[i].st_value;
|
||||
def = (struct bpf_load_map_def *)(data_maps->d_buf + offset);
|
||||
maps[i].elf_offset = offset;
|
||||
memset(&maps[i].def, 0, sizeof(struct bpf_load_map_def));
|
||||
memcpy(&maps[i].def, def, map_sz_copy);
|
||||
|
||||
/* Verify no newer features were requested */
|
||||
if (validate_zero) {
|
||||
addr = (unsigned char *) def + map_sz_copy;
|
||||
end = (unsigned char *) def + map_sz_elf;
|
||||
for (; addr < end; addr++) {
|
||||
if (*addr != 0) {
|
||||
free(sym);
|
||||
return -EFBIG;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
free(sym);
|
||||
return nr_maps;
|
||||
}
|
||||
|
||||
static int do_load_bpf_file(const char *path, fixup_map_cb fixup_map)
|
||||
{
|
||||
int fd, i, ret, maps_shndx = -1, strtabidx = -1;
|
||||
Elf *elf;
|
||||
GElf_Ehdr ehdr;
|
||||
GElf_Shdr shdr, shdr_prog;
|
||||
Elf_Data *data, *data_prog, *data_maps = NULL, *symbols = NULL;
|
||||
char *shname, *shname_prog;
|
||||
int nr_maps = 0;
|
||||
|
||||
/* reset global variables */
|
||||
kern_version = 0;
|
||||
memset(license, 0, sizeof(license));
|
||||
memset(processed_sec, 0, sizeof(processed_sec));
|
||||
|
||||
if (elf_version(EV_CURRENT) == EV_NONE)
|
||||
return 1;
|
||||
|
||||
fd = open(path, O_RDONLY, 0);
|
||||
if (fd < 0)
|
||||
return 1;
|
||||
|
||||
elf = elf_begin(fd, ELF_C_READ, NULL);
|
||||
|
||||
if (!elf)
|
||||
return 1;
|
||||
|
||||
if (gelf_getehdr(elf, &ehdr) != &ehdr)
|
||||
return 1;
|
||||
|
||||
/* clear all kprobes */
|
||||
i = write_kprobe_events("");
|
||||
|
||||
/* scan over all elf sections to get license and map info */
|
||||
for (i = 1; i < ehdr.e_shnum; i++) {
|
||||
|
||||
if (get_sec(elf, i, &ehdr, &shname, &shdr, &data))
|
||||
continue;
|
||||
|
||||
if (0) /* helpful for llvm debugging */
|
||||
printf("section %d:%s data %p size %zd link %d flags %d\n",
|
||||
i, shname, data->d_buf, data->d_size,
|
||||
shdr.sh_link, (int) shdr.sh_flags);
|
||||
|
||||
if (strcmp(shname, "license") == 0) {
|
||||
processed_sec[i] = true;
|
||||
memcpy(license, data->d_buf, data->d_size);
|
||||
} else if (strcmp(shname, "version") == 0) {
|
||||
processed_sec[i] = true;
|
||||
if (data->d_size != sizeof(int)) {
|
||||
printf("invalid size of version section %zd\n",
|
||||
data->d_size);
|
||||
return 1;
|
||||
}
|
||||
memcpy(&kern_version, data->d_buf, sizeof(int));
|
||||
} else if (strcmp(shname, "maps") == 0) {
|
||||
int j;
|
||||
|
||||
maps_shndx = i;
|
||||
data_maps = data;
|
||||
for (j = 0; j < MAX_MAPS; j++)
|
||||
map_data[j].fd = -1;
|
||||
} else if (shdr.sh_type == SHT_SYMTAB) {
|
||||
strtabidx = shdr.sh_link;
|
||||
symbols = data;
|
||||
}
|
||||
}
|
||||
|
||||
ret = 1;
|
||||
|
||||
if (!symbols) {
|
||||
printf("missing SHT_SYMTAB section\n");
|
||||
goto done;
|
||||
}
|
||||
|
||||
if (data_maps) {
|
||||
nr_maps = load_elf_maps_section(map_data, maps_shndx,
|
||||
elf, symbols, strtabidx);
|
||||
if (nr_maps < 0) {
|
||||
printf("Error: Failed loading ELF maps (errno:%d):%s\n",
|
||||
nr_maps, strerror(-nr_maps));
|
||||
goto done;
|
||||
}
|
||||
if (load_maps(map_data, nr_maps, fixup_map))
|
||||
goto done;
|
||||
map_data_count = nr_maps;
|
||||
|
||||
processed_sec[maps_shndx] = true;
|
||||
}
|
||||
|
||||
/* process all relo sections, and rewrite bpf insns for maps */
|
||||
for (i = 1; i < ehdr.e_shnum; i++) {
|
||||
if (processed_sec[i])
|
||||
continue;
|
||||
|
||||
if (get_sec(elf, i, &ehdr, &shname, &shdr, &data))
|
||||
continue;
|
||||
|
||||
if (shdr.sh_type == SHT_REL) {
|
||||
struct bpf_insn *insns;
|
||||
|
||||
/* locate prog sec that need map fixup (relocations) */
|
||||
if (get_sec(elf, shdr.sh_info, &ehdr, &shname_prog,
|
||||
&shdr_prog, &data_prog))
|
||||
continue;
|
||||
|
||||
if (shdr_prog.sh_type != SHT_PROGBITS ||
|
||||
!(shdr_prog.sh_flags & SHF_EXECINSTR))
|
||||
continue;
|
||||
|
||||
insns = (struct bpf_insn *) data_prog->d_buf;
|
||||
processed_sec[i] = true; /* relo section */
|
||||
|
||||
if (parse_relo_and_apply(data, symbols, &shdr, insns,
|
||||
map_data, nr_maps))
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
||||
/* load programs */
|
||||
for (i = 1; i < ehdr.e_shnum; i++) {
|
||||
|
||||
if (processed_sec[i])
|
||||
continue;
|
||||
|
||||
if (get_sec(elf, i, &ehdr, &shname, &shdr, &data))
|
||||
continue;
|
||||
|
||||
if (memcmp(shname, "kprobe/", 7) == 0 ||
|
||||
memcmp(shname, "kretprobe/", 10) == 0 ||
|
||||
memcmp(shname, "tracepoint/", 11) == 0 ||
|
||||
memcmp(shname, "raw_tracepoint/", 15) == 0 ||
|
||||
memcmp(shname, "xdp", 3) == 0 ||
|
||||
memcmp(shname, "perf_event", 10) == 0 ||
|
||||
memcmp(shname, "socket", 6) == 0 ||
|
||||
memcmp(shname, "cgroup/", 7) == 0 ||
|
||||
memcmp(shname, "sockops", 7) == 0 ||
|
||||
memcmp(shname, "sk_skb", 6) == 0 ||
|
||||
memcmp(shname, "sk_msg", 6) == 0) {
|
||||
ret = load_and_attach(shname, data->d_buf,
|
||||
data->d_size);
|
||||
if (ret != 0)
|
||||
goto done;
|
||||
}
|
||||
}
|
||||
|
||||
done:
|
||||
close(fd);
|
||||
return ret;
|
||||
}
|
||||
|
||||
int load_bpf_file(char *path)
|
||||
{
|
||||
return do_load_bpf_file(path, NULL);
|
||||
}
|
||||
|
||||
int load_bpf_file_fixup_map(const char *path, fixup_map_cb fixup_map)
|
||||
{
|
||||
return do_load_bpf_file(path, fixup_map);
|
||||
}
|
||||
@ -1,57 +0,0 @@
|
||||
/* SPDX-License-Identifier: GPL-2.0 */
|
||||
#ifndef __BPF_LOAD_H
|
||||
#define __BPF_LOAD_H
|
||||
|
||||
#include <bpf/bpf.h>
|
||||
|
||||
#define MAX_MAPS 32
|
||||
#define MAX_PROGS 32
|
||||
|
||||
struct bpf_load_map_def {
|
||||
unsigned int type;
|
||||
unsigned int key_size;
|
||||
unsigned int value_size;
|
||||
unsigned int max_entries;
|
||||
unsigned int map_flags;
|
||||
unsigned int inner_map_idx;
|
||||
unsigned int numa_node;
|
||||
};
|
||||
|
||||
struct bpf_map_data {
|
||||
int fd;
|
||||
char *name;
|
||||
size_t elf_offset;
|
||||
struct bpf_load_map_def def;
|
||||
};
|
||||
|
||||
typedef void (*fixup_map_cb)(struct bpf_map_data *map, int idx);
|
||||
|
||||
extern int prog_fd[MAX_PROGS];
|
||||
extern int event_fd[MAX_PROGS];
|
||||
extern char bpf_log_buf[BPF_LOG_BUF_SIZE];
|
||||
extern int prog_cnt;
|
||||
|
||||
/* There is a one-to-one mapping between map_fd[] and map_data[].
|
||||
* The map_data[] just contains more rich info on the given map.
|
||||
*/
|
||||
extern int map_fd[MAX_MAPS];
|
||||
extern struct bpf_map_data map_data[MAX_MAPS];
|
||||
extern int map_data_count;
|
||||
|
||||
/* parses elf file compiled by llvm .c->.o
|
||||
* . parses 'maps' section and creates maps via BPF syscall
|
||||
* . parses 'license' section and passes it to syscall
|
||||
* . parses elf relocations for BPF maps and adjusts BPF_LD_IMM64 insns by
|
||||
* storing map_fd into insn->imm and marking such insns as BPF_PSEUDO_MAP_FD
|
||||
* . loads eBPF programs via BPF syscall
|
||||
*
|
||||
* One ELF file can contain multiple BPF programs which will be loaded
|
||||
* and their FDs stored stored in prog_fd array
|
||||
*
|
||||
* returns zero on success
|
||||
*/
|
||||
int load_bpf_file(char *path);
|
||||
int load_bpf_file_fixup_map(const char *path, fixup_map_cb fixup_map);
|
||||
|
||||
int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
|
||||
#endif
|
||||
@ -6,7 +6,7 @@
|
||||
* This uses the XDP data_meta infrastructure, and is a cooperation
|
||||
* between two bpf-programs (1) XDP and (2) clsact at TC-ingress hook.
|
||||
*
|
||||
* Notice: This example does not use the BPF C-loader (bpf_load.c),
|
||||
* Notice: This example does not use the BPF C-loader,
|
||||
* but instead rely on the iproute2 TC tool for loading BPF-objects.
|
||||
*/
|
||||
#include <uapi/linux/bpf.h>
|
||||
|
||||
Loading…
Reference in New Issue
Block a user