samples: bpf: Remove bpf_load loader completely (ceb5dea5) · Commits · 戴 / test

samples/bpf/Makefile

+4 −6

Original line number	Diff line number	Diff line
		@@ -73,7 +73,7 @@ tracex5-objs := tracex5_user.o $(TRACE_HELPERS)
		tracex6-objs := tracex6_user.o
		tracex7-objs := tracex7_user.o
		test_probe_write_user-objs := test_probe_write_user_user.o
		trace_output-objs := trace_output_user.o $(TRACE_HELPERS)
		trace_output-objs := trace_output_user.o
		lathist-objs := lathist_user.o
		offwaketime-objs := offwaketime_user.o $(TRACE_HELPERS)
		spintest-objs := spintest_user.o $(TRACE_HELPERS)
		@@ -91,8 +91,8 @@ test_current_task_under_cgroup-objs := $(CGROUP_HELPERS) \
		test_current_task_under_cgroup_user.o
		trace_event-objs := trace_event_user.o $(TRACE_HELPERS)
		sampleip-objs := sampleip_user.o $(TRACE_HELPERS)
		tc_l2_redirect-objs := bpf_load.o tc_l2_redirect_user.o
		lwt_len_hist-objs := bpf_load.o lwt_len_hist_user.o
		tc_l2_redirect-objs := tc_l2_redirect_user.o
		lwt_len_hist-objs := lwt_len_hist_user.o
		xdp_tx_iptunnel-objs := xdp_tx_iptunnel_user.o
		test_map_in_map-objs := test_map_in_map_user.o
		per_socket_stats_example-objs := cookie_uid_helper_example.o
		@@ -108,7 +108,7 @@ xdpsock-objs := xdpsock_user.o
		xsk_fwd-objs := xsk_fwd.o
		xdp_fwd-objs := xdp_fwd_user.o
		task_fd_query-objs := task_fd_query_user.o $(TRACE_HELPERS)
		xdp_sample_pkts-objs := xdp_sample_pkts_user.o $(TRACE_HELPERS)
		xdp_sample_pkts-objs := xdp_sample_pkts_user.o
		ibumad-objs := ibumad_user.o
		hbm-objs := hbm.o $(CGROUP_HELPERS)

		@@ -197,8 +197,6 @@ TPROGS_CFLAGS += --sysroot=$(SYSROOT)
		TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
		endif

		TPROGCFLAGS_bpf_load.o += -Wno-unused-variable

		TPROGS_LDLIBS += $(LIBBPF) -lelf -lz
		TPROGLDLIBS_tracex4 += -lrt
		TPROGLDLIBS_trace_output += -lrt

samples/bpf/bpf_load.c

deleted100644 → 0

+0 −667

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		#include <stdio.h>
		#include <sys/types.h>
		#include <sys/stat.h>
		#include <fcntl.h>
		#include <libelf.h>
		#include <gelf.h>
		#include <errno.h>
		#include <unistd.h>
		#include <string.h>
		#include <stdbool.h>
		#include <stdlib.h>
		#include <linux/bpf.h>
		#include <linux/filter.h>
		#include <linux/perf_event.h>
		#include <linux/netlink.h>
		#include <linux/rtnetlink.h>
		#include <linux/types.h>
		#include <sys/socket.h>
		#include <sys/syscall.h>
		#include <sys/ioctl.h>
		#include <sys/mman.h>
		#include <poll.h>
		#include <ctype.h>
		#include <assert.h>
		#include <bpf/bpf.h>
		#include "bpf_load.h"
		#include "perf-sys.h"

		#define DEBUGFS "/sys/kernel/debug/tracing/"

		static char license[128];
		static int kern_version;
		static bool processed_sec[128];
		char bpf_log_buf[BPF_LOG_BUF_SIZE];
		int map_fd[MAX_MAPS];
		int prog_fd[MAX_PROGS];
		int event_fd[MAX_PROGS];
		int prog_cnt;
		int prog_array_fd = -1;

		struct bpf_map_data map_data[MAX_MAPS];
		int map_data_count;

		static int populate_prog_array(const char *event, int prog_fd)
		{
		int ind = atoi(event), err;

		err = bpf_map_update_elem(prog_array_fd, &ind, &prog_fd, BPF_ANY);
		if (err < 0) {
		printf("failed to store prog_fd in prog_array\n");
		return -1;
		}
		return 0;
		}

		static int write_kprobe_events(const char *val)
		{
		int fd, ret, flags;

		if (val == NULL)
		return -1;
		else if (val[0] == '\0')
		flags = O_WRONLY \| O_TRUNC;
		else
		flags = O_WRONLY \| O_APPEND;

		fd = open(DEBUGFS "kprobe_events", flags);

		ret = write(fd, val, strlen(val));
		close(fd);

		return ret;
		}

		static int load_and_attach(const char event, struct bpf_insn prog, int size)
		{
		bool is_socket = strncmp(event, "socket", 6) == 0;
		bool is_kprobe = strncmp(event, "kprobe/", 7) == 0;
		bool is_kretprobe = strncmp(event, "kretprobe/", 10) == 0;
		bool is_tracepoint = strncmp(event, "tracepoint/", 11) == 0;
		bool is_raw_tracepoint = strncmp(event, "raw_tracepoint/", 15) == 0;
		bool is_xdp = strncmp(event, "xdp", 3) == 0;
		bool is_perf_event = strncmp(event, "perf_event", 10) == 0;
		bool is_cgroup_skb = strncmp(event, "cgroup/skb", 10) == 0;
		bool is_cgroup_sk = strncmp(event, "cgroup/sock", 11) == 0;
		bool is_sockops = strncmp(event, "sockops", 7) == 0;
		bool is_sk_skb = strncmp(event, "sk_skb", 6) == 0;
		bool is_sk_msg = strncmp(event, "sk_msg", 6) == 0;
		size_t insns_cnt = size / sizeof(struct bpf_insn);
		enum bpf_prog_type prog_type;
		char buf[256];
		int fd, efd, err, id;
		struct perf_event_attr attr = {};

		attr.type = PERF_TYPE_TRACEPOINT;
		attr.sample_type = PERF_SAMPLE_RAW;
		attr.sample_period = 1;
		attr.wakeup_events = 1;

		if (is_socket) {
		prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
		} else if (is_kprobe \|\| is_kretprobe) {
		prog_type = BPF_PROG_TYPE_KPROBE;
		} else if (is_tracepoint) {
		prog_type = BPF_PROG_TYPE_TRACEPOINT;
		} else if (is_raw_tracepoint) {
		prog_type = BPF_PROG_TYPE_RAW_TRACEPOINT;
		} else if (is_xdp) {
		prog_type = BPF_PROG_TYPE_XDP;
		} else if (is_perf_event) {
		prog_type = BPF_PROG_TYPE_PERF_EVENT;
		} else if (is_cgroup_skb) {
		prog_type = BPF_PROG_TYPE_CGROUP_SKB;
		} else if (is_cgroup_sk) {
		prog_type = BPF_PROG_TYPE_CGROUP_SOCK;
		} else if (is_sockops) {
		prog_type = BPF_PROG_TYPE_SOCK_OPS;
		} else if (is_sk_skb) {
		prog_type = BPF_PROG_TYPE_SK_SKB;
		} else if (is_sk_msg) {
		prog_type = BPF_PROG_TYPE_SK_MSG;
		} else {
		printf("Unknown event '%s'\n", event);
		return -1;
		}

		if (prog_cnt == MAX_PROGS)
		return -1;

		fd = bpf_load_program(prog_type, prog, insns_cnt, license, kern_version,
		bpf_log_buf, BPF_LOG_BUF_SIZE);
		if (fd < 0) {
		printf("bpf_load_program() err=%d\n%s", errno, bpf_log_buf);
		return -1;
		}

		prog_fd[prog_cnt++] = fd;

		if (is_xdp \|\| is_perf_event \|\| is_cgroup_skb \|\| is_cgroup_sk)
		return 0;

		if (is_socket \|\| is_sockops \|\| is_sk_skb \|\| is_sk_msg) {
		if (is_socket)
		event += 6;
		else
		event += 7;
		if (*event != '/')
		return 0;
		event++;
		if (!isdigit(*event)) {
		printf("invalid prog number\n");
		return -1;
		}
		return populate_prog_array(event, fd);
		}

		if (is_raw_tracepoint) {
		efd = bpf_raw_tracepoint_open(event + 15, fd);
		if (efd < 0) {
		printf("tracepoint %s %s\n", event + 15, strerror(errno));
		return -1;
		}
		event_fd[prog_cnt - 1] = efd;
		return 0;
		}

		if (is_kprobe \|\| is_kretprobe) {
		bool need_normal_check = true;
		const char *event_prefix = "";

		if (is_kprobe)
		event += 7;
		else
		event += 10;

		if (*event == 0) {
		printf("event name cannot be empty\n");
		return -1;
		}

		if (isdigit(*event))
		return populate_prog_array(event, fd);

		#ifdef __x86_64__
		if (strncmp(event, "sys_", 4) == 0) {
		snprintf(buf, sizeof(buf), "%c:__x64_%s __x64_%s",
		is_kprobe ? 'p' : 'r', event, event);
		err = write_kprobe_events(buf);
		if (err >= 0) {
		need_normal_check = false;
		event_prefix = "__x64_";
		}
		}
		#endif
		if (need_normal_check) {
		snprintf(buf, sizeof(buf), "%c:%s %s",
		is_kprobe ? 'p' : 'r', event, event);
		err = write_kprobe_events(buf);
		if (err < 0) {
		printf("failed to create kprobe '%s' error '%s'\n",
		event, strerror(errno));
		return -1;
		}
		}

		strcpy(buf, DEBUGFS);
		strcat(buf, "events/kprobes/");
		strcat(buf, event_prefix);
		strcat(buf, event);
		strcat(buf, "/id");
		} else if (is_tracepoint) {
		event += 11;

		if (*event == 0) {
		printf("event name cannot be empty\n");
		return -1;
		}
		strcpy(buf, DEBUGFS);
		strcat(buf, "events/");
		strcat(buf, event);
		strcat(buf, "/id");
		}

		efd = open(buf, O_RDONLY, 0);
		if (efd < 0) {
		printf("failed to open event %s\n", event);
		return -1;
		}

		err = read(efd, buf, sizeof(buf));
		if (err < 0 \|\| err >= sizeof(buf)) {
		printf("read from '%s' failed '%s'\n", event, strerror(errno));
		return -1;
		}

		close(efd);

		buf[err] = 0;
		id = atoi(buf);
		attr.config = id;

		efd = sys_perf_event_open(&attr, -1/pid/, 0/cpu/, -1/group_fd/, 0);
		if (efd < 0) {
		printf("event %d fd %d err %s\n", id, efd, strerror(errno));
		return -1;
		}
		event_fd[prog_cnt - 1] = efd;
		err = ioctl(efd, PERF_EVENT_IOC_ENABLE, 0);
		if (err < 0) {
		printf("ioctl PERF_EVENT_IOC_ENABLE failed err %s\n",
		strerror(errno));
		return -1;
		}
		err = ioctl(efd, PERF_EVENT_IOC_SET_BPF, fd);
		if (err < 0) {
		printf("ioctl PERF_EVENT_IOC_SET_BPF failed err %s\n",
		strerror(errno));
		return -1;
		}

		return 0;
		}

		static int load_maps(struct bpf_map_data *maps, int nr_maps,
		fixup_map_cb fixup_map)
		{
		int i, numa_node;

		for (i = 0; i < nr_maps; i++) {
		if (fixup_map) {
		fixup_map(&maps[i], i);
		/* Allow userspace to assign map FD prior to creation */
		if (maps[i].fd != -1) {
		map_fd[i] = maps[i].fd;
		continue;
		}
		}

		numa_node = maps[i].def.map_flags & BPF_F_NUMA_NODE ?
		maps[i].def.numa_node : -1;

		if (maps[i].def.type == BPF_MAP_TYPE_ARRAY_OF_MAPS \|\|
		maps[i].def.type == BPF_MAP_TYPE_HASH_OF_MAPS) {
		int inner_map_fd = map_fd[maps[i].def.inner_map_idx];

		map_fd[i] = bpf_create_map_in_map_node(maps[i].def.type,
		maps[i].name,
		maps[i].def.key_size,
		inner_map_fd,
		maps[i].def.max_entries,
		maps[i].def.map_flags,
		numa_node);
		} else {
		map_fd[i] = bpf_create_map_node(maps[i].def.type,
		maps[i].name,
		maps[i].def.key_size,
		maps[i].def.value_size,
		maps[i].def.max_entries,
		maps[i].def.map_flags,
		numa_node);
		}
		if (map_fd[i] < 0) {
		printf("failed to create map %d (%s): %d %s\n",
		i, maps[i].name, errno, strerror(errno));
		return 1;
		}
		maps[i].fd = map_fd[i];

		if (maps[i].def.type == BPF_MAP_TYPE_PROG_ARRAY)
		prog_array_fd = map_fd[i];
		}
		return 0;
		}

		static int get_sec(Elf elf, int i, GElf_Ehdr ehdr, char **shname,
		GElf_Shdr shdr, Elf_Data *data)
		{
		Elf_Scn *scn;

		scn = elf_getscn(elf, i);
		if (!scn)
		return 1;

		if (gelf_getshdr(scn, shdr) != shdr)
		return 2;

		*shname = elf_strptr(elf, ehdr->e_shstrndx, shdr->sh_name);
		if (!*shname \|\| !shdr->sh_size)
		return 3;

		*data = elf_getdata(scn, 0);
		if (!data \|\| elf_getdata(scn, data) != NULL)
		return 4;

		return 0;
		}

		static int parse_relo_and_apply(Elf_Data data, Elf_Data symbols,
		GElf_Shdr shdr, struct bpf_insn insn,
		struct bpf_map_data *maps, int nr_maps)
		{
		int i, nrels;

		nrels = shdr->sh_size / shdr->sh_entsize;

		for (i = 0; i < nrels; i++) {
		GElf_Sym sym;
		GElf_Rel rel;
		unsigned int insn_idx;
		bool match = false;
		int j, map_idx;

		gelf_getrel(data, i, &rel);

		insn_idx = rel.r_offset / sizeof(struct bpf_insn);

		gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym);

		if (insn[insn_idx].code != (BPF_LD \| BPF_IMM \| BPF_DW)) {
		printf("invalid relo for insn[%d].code 0x%x\n",
		insn_idx, insn[insn_idx].code);
		return 1;
		}
		insn[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;

		/* Match FD relocation against recorded map_data[] offset */
		for (map_idx = 0; map_idx < nr_maps; map_idx++) {
		if (maps[map_idx].elf_offset == sym.st_value) {
		match = true;
		break;
		}
		}
		if (match) {
		insn[insn_idx].imm = maps[map_idx].fd;
		} else {
		printf("invalid relo for insn[%d] no map_data match\n",
		insn_idx);
		return 1;
		}
		}

		return 0;
		}

		static int cmp_symbols(const void l, const void r)
		{
		const GElf_Sym lsym = (const GElf_Sym )l;
		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);
		}

samples/bpf/bpf_load.h

deleted100644 → 0

+0 −57

Original line number	Diff line number	Diff line
		/* 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

samples/bpf/xdp2skb_meta_kern.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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>

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