[mirror_ubuntu-eoan-kernel.git] / samples / bpf / bpf_load.c

// 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/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 = 0;

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 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),
				 "echo '%c:__x64_%s __x64_%s' >> /sys/kernel/debug/tracing/kprobe_events",
				 is_kprobe ? 'p' : 'r', event, event);
			err = system(buf);
			if (err >= 0) {
				need_normal_check = false;
				event_prefix = "__x64_";
			}
		}
#endif
		if (need_normal_check) {
			snprintf(buf, sizeof(buf),
				 "echo '%c:%s %s' >> /sys/kernel/debug/tracing/kprobe_events",
				 is_kprobe ? 'p' : 'r', event, event);
			err = system(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 a map: %d %s\n",
			       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 = system("echo \"\" > /sys/kernel/debug/tracing/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);
}

void read_trace_pipe(void)
{
	int trace_fd;

	trace_fd = open(DEBUGFS "trace_pipe", O_RDONLY, 0);
	if (trace_fd < 0)
		return;

	while (1) {
		static char buf[4096];
		ssize_t sz;

		sz = read(trace_fd, buf, sizeof(buf));
		if (sz > 0) {
			buf[sz] = 0;
			puts(buf);
		}
	}
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
249b812d AS	2	#include <stdio.h>
	3	#include <sys/types.h>
	4	#include <sys/stat.h>
	5	#include <fcntl.h>
	6	#include <libelf.h>
	7	#include <gelf.h>
	8	#include <errno.h>
	9	#include <unistd.h>
	10	#include <string.h>
	11	#include <stdbool.h>
b896c4f9	12	#include <stdlib.h>
249b812d AS	13	#include <linux/bpf.h>
249b812d AS	14	#include <linux/filter.h>
b896c4f9	15	#include <linux/perf_event.h>
12d8bb64 MKL	16	#include <linux/netlink.h>
12d8bb64 MKL	17	#include <linux/rtnetlink.h>
6387d011	18	#include <linux/types.h>
12d8bb64 MKL	19	#include <sys/types.h>
12d8bb64 MKL	20	#include <sys/socket.h>
b896c4f9 AS	21	#include <sys/syscall.h>
	22	#include <sys/ioctl.h>
	23	#include <sys/mman.h>
	24	#include <poll.h>
5bacd780	25	#include <ctype.h>
9fd63d05	26	#include <assert.h>
2bf3e2ef	27	#include <bpf/bpf.h>
249b812d	28	#include "bpf_load.h"
205c8ada	29	#include "perf-sys.h"
249b812d	30
b896c4f9 AS	31	#define DEBUGFS "/sys/kernel/debug/tracing/"
b896c4f9 AS	32
249b812d	33	static char license[128];
b896c4f9	34	static int kern_version;
249b812d	35	static bool processed_sec[128];
d40fc181	36	char bpf_log_buf[BPF_LOG_BUF_SIZE];
249b812d AS	37	int map_fd[MAX_MAPS];
249b812d AS	38	int prog_fd[MAX_PROGS];
b896c4f9	39	int event_fd[MAX_PROGS];
249b812d	40	int prog_cnt;
5bacd780 AS	41	int prog_array_fd = -1;
5bacd780 AS	42
156450d9 JDB	43	struct bpf_map_data map_data[MAX_MAPS];
	44	int map_data_count = 0;
	45
5bacd780 AS	46	static int populate_prog_array(const char *event, int prog_fd)
	47	{
	48	int ind = atoi(event), err;
	49
d40fc181	50	err = bpf_map_update_elem(prog_array_fd, &ind, &prog_fd, BPF_ANY);
5bacd780 AS	51	if (err < 0) {
	52	printf("failed to store prog_fd in prog_array\n");
	53	return -1;
	54	}
	55	return 0;
	56	}
249b812d AS	57
	58	static int load_and_attach(const char event, struct bpf_insn prog, int size)
	59	{
249b812d	60	bool is_socket = strncmp(event, "socket", 6) == 0;
b896c4f9 AS	61	bool is_kprobe = strncmp(event, "kprobe/", 7) == 0;
b896c4f9 AS	62	bool is_kretprobe = strncmp(event, "kretprobe/", 10) == 0;
c0766040	63	bool is_tracepoint = strncmp(event, "tracepoint/", 11) == 0;
4662a4e5	64	bool is_raw_tracepoint = strncmp(event, "raw_tracepoint/", 15) == 0;
86af8b41	65	bool is_xdp = strncmp(event, "xdp", 3) == 0;
1c47910e	66	bool is_perf_event = strncmp(event, "perf_event", 10) == 0;
4f2e7ae5 DA	67	bool is_cgroup_skb = strncmp(event, "cgroup/skb", 10) == 0;
4f2e7ae5 DA	68	bool is_cgroup_sk = strncmp(event, "cgroup/sock", 11) == 0;
40304b2a	69	bool is_sockops = strncmp(event, "sockops", 7) == 0;
69e8cc13	70	bool is_sk_skb = strncmp(event, "sk_skb", 6) == 0;
4c4c3c27	71	bool is_sk_msg = strncmp(event, "sk_msg", 6) == 0;
43371c83	72	size_t insns_cnt = size / sizeof(struct bpf_insn);
b896c4f9 AS	73	enum bpf_prog_type prog_type;
	74	char buf[256];
	75	int fd, efd, err, id;
	76	struct perf_event_attr attr = {};
	77
	78	attr.type = PERF_TYPE_TRACEPOINT;
	79	attr.sample_type = PERF_SAMPLE_RAW;
	80	attr.sample_period = 1;
	81	attr.wakeup_events = 1;
	82
	83	if (is_socket) {
	84	prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
	85	} else if (is_kprobe \|\| is_kretprobe) {
	86	prog_type = BPF_PROG_TYPE_KPROBE;
c0766040 AS	87	} else if (is_tracepoint) {
c0766040 AS	88	prog_type = BPF_PROG_TYPE_TRACEPOINT;
4662a4e5 AS	89	} else if (is_raw_tracepoint) {
4662a4e5 AS	90	prog_type = BPF_PROG_TYPE_RAW_TRACEPOINT;
86af8b41 BB	91	} else if (is_xdp) {
86af8b41 BB	92	prog_type = BPF_PROG_TYPE_XDP;
1c47910e AS	93	} else if (is_perf_event) {
1c47910e AS	94	prog_type = BPF_PROG_TYPE_PERF_EVENT;
4f2e7ae5 DA	95	} else if (is_cgroup_skb) {
	96	prog_type = BPF_PROG_TYPE_CGROUP_SKB;
	97	} else if (is_cgroup_sk) {
	98	prog_type = BPF_PROG_TYPE_CGROUP_SOCK;
40304b2a LB	99	} else if (is_sockops) {
40304b2a LB	100	prog_type = BPF_PROG_TYPE_SOCK_OPS;
69e8cc13 JF	101	} else if (is_sk_skb) {
69e8cc13 JF	102	prog_type = BPF_PROG_TYPE_SK_SKB;
4c4c3c27 JF	103	} else if (is_sk_msg) {
4c4c3c27 JF	104	prog_type = BPF_PROG_TYPE_SK_MSG;
b896c4f9 AS	105	} else {
b896c4f9 AS	106	printf("Unknown event '%s'\n", event);
249b812d	107	return -1;
b896c4f9 AS	108	}
b896c4f9 AS	109
b0294bc1 DC	110	if (prog_cnt == MAX_PROGS)
	111	return -1;
	112
43371c83	113	fd = bpf_load_program(prog_type, prog, insns_cnt, license, kern_version,
d40fc181	114	bpf_log_buf, BPF_LOG_BUF_SIZE);
5bacd780	115	if (fd < 0) {
d40fc181	116	printf("bpf_load_program() err=%d\n%s", errno, bpf_log_buf);
5bacd780 AS	117	return -1;
	118	}
	119
	120	prog_fd[prog_cnt++] = fd;
	121
4f2e7ae5	122	if (is_xdp \|\| is_perf_event \|\| is_cgroup_skb \|\| is_cgroup_sk)
86af8b41 BB	123	return 0;
86af8b41 BB	124
4c4c3c27	125	if (is_socket \|\| is_sockops \|\| is_sk_skb \|\| is_sk_msg) {
40304b2a LB	126	if (is_socket)
	127	event += 6;
	128	else
	129	event += 7;
5bacd780 AS	130	if (*event != '/')
	131	return 0;
	132	event++;
	133	if (!isdigit(*event)) {
	134	printf("invalid prog number\n");
	135	return -1;
	136	}
	137	return populate_prog_array(event, fd);
	138	}
	139
4662a4e5 AS	140	if (is_raw_tracepoint) {
	141	efd = bpf_raw_tracepoint_open(event + 15, fd);
	142	if (efd < 0) {
	143	printf("tracepoint %s %s\n", event + 15, strerror(errno));
	144	return -1;
	145	}
	146	event_fd[prog_cnt - 1] = efd;
	147	return 0;
	148	}
	149
b896c4f9	150	if (is_kprobe \|\| is_kretprobe) {
34745aed YS	151	bool need_normal_check = true;
	152	const char *event_prefix = "";
	153
b896c4f9 AS	154	if (is_kprobe)
	155	event += 7;
	156	else
	157	event += 10;
	158
5bacd780 AS	159	if (*event == 0) {
	160	printf("event name cannot be empty\n");
	161	return -1;
	162	}
	163
	164	if (isdigit(*event))
	165	return populate_prog_array(event, fd);
	166
34745aed YS	167	#ifdef __x86_64__
	168	if (strncmp(event, "sys_", 4) == 0) {
	169	snprintf(buf, sizeof(buf),
	170	"echo '%c:__x64_%s __x64_%s' >> /sys/kernel/debug/tracing/kprobe_events",
	171	is_kprobe ? 'p' : 'r', event, event);
	172	err = system(buf);
	173	if (err >= 0) {
	174	need_normal_check = false;
	175	event_prefix = "__x64_";
	176	}
	177	}
	178	#endif
	179	if (need_normal_check) {
	180	snprintf(buf, sizeof(buf),
	181	"echo '%c:%s %s' >> /sys/kernel/debug/tracing/kprobe_events",
	182	is_kprobe ? 'p' : 'r', event, event);
	183	err = system(buf);
	184	if (err < 0) {
	185	printf("failed to create kprobe '%s' error '%s'\n",
	186	event, strerror(errno));
	187	return -1;
	188	}
b896c4f9	189	}
249b812d	190
c0766040 AS	191	strcpy(buf, DEBUGFS);
c0766040 AS	192	strcat(buf, "events/kprobes/");
34745aed	193	strcat(buf, event_prefix);
c0766040 AS	194	strcat(buf, event);
	195	strcat(buf, "/id");
	196	} else if (is_tracepoint) {
	197	event += 11;
	198
	199	if (*event == 0) {
	200	printf("event name cannot be empty\n");
	201	return -1;
	202	}
	203	strcpy(buf, DEBUGFS);
	204	strcat(buf, "events/");
	205	strcat(buf, event);
	206	strcat(buf, "/id");
	207	}
b896c4f9 AS	208
	209	efd = open(buf, O_RDONLY, 0);
	210	if (efd < 0) {
	211	printf("failed to open event %s\n", event);
	212	return -1;
	213	}
	214
	215	err = read(efd, buf, sizeof(buf));
	216	if (err < 0 \|\| err >= sizeof(buf)) {
	217	printf("read from '%s' failed '%s'\n", event, strerror(errno));
	218	return -1;
	219	}
	220
	221	close(efd);
	222
	223	buf[err] = 0;
	224	id = atoi(buf);
	225	attr.config = id;
	226
205c8ada	227	efd = sys_perf_event_open(&attr, -1/pid/, 0/cpu/, -1/group_fd/, 0);
b896c4f9 AS	228	if (efd < 0) {
	229	printf("event %d fd %d err %s\n", id, efd, strerror(errno));
	230	return -1;
	231	}
	232	event_fd[prog_cnt - 1] = efd;
0ec9552b YS	233	err = ioctl(efd, PERF_EVENT_IOC_ENABLE, 0);
	234	if (err < 0) {
	235	printf("ioctl PERF_EVENT_IOC_ENABLE failed err %s\n",
	236	strerror(errno));
	237	return -1;
	238	}
	239	err = ioctl(efd, PERF_EVENT_IOC_SET_BPF, fd);
	240	if (err < 0) {
	241	printf("ioctl PERF_EVENT_IOC_SET_BPF failed err %s\n",
	242	strerror(errno));
	243	return -1;
	244	}
b896c4f9	245
249b812d AS	246	return 0;
	247	}
	248
156450d9 JDB	249	static int load_maps(struct bpf_map_data *maps, int nr_maps,
156450d9 JDB	250	fixup_map_cb fixup_map)
249b812d	251	{
ad17d0e6	252	int i, numa_node;
156450d9	253
5010e948	254	for (i = 0; i < nr_maps; i++) {
6979bcc7 JDB	255	if (fixup_map) {
	256	fixup_map(&maps[i], i);
	257	/* Allow userspace to assign map FD prior to creation */
	258	if (maps[i].fd != -1) {
	259	map_fd[i] = maps[i].fd;
	260	continue;
	261	}
	262	}
249b812d	263
ad17d0e6 MKL	264	numa_node = maps[i].def.map_flags & BPF_F_NUMA_NODE ?
	265	maps[i].def.numa_node : -1;
	266
156450d9 JDB	267	if (maps[i].def.type == BPF_MAP_TYPE_ARRAY_OF_MAPS \|\|
	268	maps[i].def.type == BPF_MAP_TYPE_HASH_OF_MAPS) {
	269	int inner_map_fd = map_fd[maps[i].def.inner_map_idx];
fb30d4b7	270
ad17d0e6	271	map_fd[i] = bpf_create_map_in_map_node(maps[i].def.type,
88cda1c9	272	maps[i].name,
156450d9 JDB	273	maps[i].def.key_size,
	274	inner_map_fd,
	275	maps[i].def.max_entries,
ad17d0e6 MKL	276	maps[i].def.map_flags,
ad17d0e6 MKL	277	numa_node);
fb30d4b7	278	} else {
ad17d0e6	279	map_fd[i] = bpf_create_map_node(maps[i].def.type,
88cda1c9	280	maps[i].name,
ad17d0e6 MKL	281	maps[i].def.key_size,
	282	maps[i].def.value_size,
	283	maps[i].def.max_entries,
	284	maps[i].def.map_flags,
	285	numa_node);
fb30d4b7	286	}
618ec9a7 AS	287	if (map_fd[i] < 0) {
	288	printf("failed to create a map: %d %s\n",
	289	errno, strerror(errno));
249b812d	290	return 1;
618ec9a7	291	}
156450d9	292	maps[i].fd = map_fd[i];
5bacd780	293
156450d9	294	if (maps[i].def.type == BPF_MAP_TYPE_PROG_ARRAY)
5bacd780	295	prog_array_fd = map_fd[i];
249b812d AS	296	}
	297	return 0;
	298	}
	299
	300	static int get_sec(Elf elf, int i, GElf_Ehdr ehdr, char **shname,
	301	GElf_Shdr shdr, Elf_Data *data)
	302	{
	303	Elf_Scn *scn;
	304
	305	scn = elf_getscn(elf, i);
	306	if (!scn)
	307	return 1;
	308
	309	if (gelf_getshdr(scn, shdr) != shdr)
	310	return 2;
	311
	312	*shname = elf_strptr(elf, ehdr->e_shstrndx, shdr->sh_name);
	313	if (!*shname \|\| !shdr->sh_size)
	314	return 3;
	315
	316	*data = elf_getdata(scn, 0);
	317	if (!data \|\| elf_getdata(scn, data) != NULL)
	318	return 4;
	319
	320	return 0;
	321	}
	322
	323	static int parse_relo_and_apply(Elf_Data data, Elf_Data symbols,
156450d9 JDB	324	GElf_Shdr shdr, struct bpf_insn insn,
156450d9 JDB	325	struct bpf_map_data *maps, int nr_maps)
249b812d AS	326	{
	327	int i, nrels;
	328
	329	nrels = shdr->sh_size / shdr->sh_entsize;
	330
	331	for (i = 0; i < nrels; i++) {
	332	GElf_Sym sym;
	333	GElf_Rel rel;
	334	unsigned int insn_idx;
156450d9 JDB	335	bool match = false;
156450d9 JDB	336	int j, map_idx;
249b812d AS	337
	338	gelf_getrel(data, i, &rel);
	339
	340	insn_idx = rel.r_offset / sizeof(struct bpf_insn);
	341
	342	gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym);
	343
	344	if (insn[insn_idx].code != (BPF_LD \| BPF_IMM \| BPF_DW)) {
	345	printf("invalid relo for insn[%d].code 0x%x\n",
	346	insn_idx, insn[insn_idx].code);
	347	return 1;
	348	}
	349	insn[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;
156450d9 JDB	350
	351	/* Match FD relocation against recorded map_data[] offset */
	352	for (map_idx = 0; map_idx < nr_maps; map_idx++) {
	353	if (maps[map_idx].elf_offset == sym.st_value) {
	354	match = true;
	355	break;
	356	}
	357	}
	358	if (match) {
	359	insn[insn_idx].imm = maps[map_idx].fd;
	360	} else {
	361	printf("invalid relo for insn[%d] no map_data match\n",
	362	insn_idx);
	363	return 1;
	364	}
249b812d AS	365	}
	366
	367	return 0;
	368	}
	369
9fd63d05 MKL	370	static int cmp_symbols(const void l, const void r)
	371	{
	372	const GElf_Sym lsym = (const GElf_Sym )l;
	373	const GElf_Sym rsym = (const GElf_Sym )r;
	374
	375	if (lsym->st_value < rsym->st_value)
	376	return -1;
	377	else if (lsym->st_value > rsym->st_value)
	378	return 1;
	379	else
	380	return 0;
	381	}
	382
156450d9 JDB	383	static int load_elf_maps_section(struct bpf_map_data *maps, int maps_shndx,
156450d9 JDB	384	Elf elf, Elf_Data symbols, int strtabidx)
9fd63d05	385	{
156450d9 JDB	386	int map_sz_elf, map_sz_copy;
	387	bool validate_zero = false;
	388	Elf_Data *data_maps;
	389	int i, nr_maps;
	390	GElf_Sym *sym;
	391	Elf_Scn *scn;
	392	int copy_sz;
	393
	394	if (maps_shndx < 0)
	395	return -EINVAL;
	396	if (!symbols)
	397	return -EINVAL;
	398
	399	/* Get data for maps section via elf index */
	400	scn = elf_getscn(elf, maps_shndx);
	401	if (scn)
	402	data_maps = elf_getdata(scn, NULL);
	403	if (!scn \|\| !data_maps) {
	404	printf("Failed to get Elf_Data from maps section %d\n",
	405	maps_shndx);
	406	return -EINVAL;
	407	}
9fd63d05	408
156450d9 JDB	409	/* For each map get corrosponding symbol table entry */
	410	sym = calloc(MAX_MAPS+1, sizeof(GElf_Sym));
	411	for (i = 0, nr_maps = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
	412	assert(nr_maps < MAX_MAPS+1);
	413	if (!gelf_getsym(symbols, i, &sym[nr_maps]))
9fd63d05	414	continue;
156450d9	415	if (sym[nr_maps].st_shndx != maps_shndx)
9fd63d05	416	continue;
156450d9	417	/* Only increment iif maps section */
9fd63d05 MKL	418	nr_maps++;
	419	}
	420
156450d9 JDB	421	/* Align to map_fd[] order, via sort on offset in sym.st_value */
	422	qsort(sym, nr_maps, sizeof(GElf_Sym), cmp_symbols);
	423
	424	/* Keeping compatible with ELF maps section changes
	425	* ------------------------------------------------
74662ea5	426	* The program size of struct bpf_load_map_def is known by loader
156450d9 JDB	427	* code, but struct stored in ELF file can be different.
	428	*
	429	* Unfortunately sym[i].st_size is zero. To calculate the
	430	* struct size stored in the ELF file, assume all struct have
	431	* the same size, and simply divide with number of map
	432	* symbols.
	433	*/
	434	map_sz_elf = data_maps->d_size / nr_maps;
74662ea5	435	map_sz_copy = sizeof(struct bpf_load_map_def);
156450d9 JDB	436	if (map_sz_elf < map_sz_copy) {
	437	/*
	438	* Backward compat, loading older ELF file with
	439	* smaller struct, keeping remaining bytes zero.
	440	*/
	441	map_sz_copy = map_sz_elf;
	442	} else if (map_sz_elf > map_sz_copy) {
	443	/*
	444	* Forward compat, loading newer ELF file with larger
	445	* struct with unknown features. Assume zero means
	446	* feature not used. Thus, validate rest of struct
	447	* data is zero.
	448	*/
	449	validate_zero = true;
	450	}
9fd63d05	451
156450d9	452	/* Memcpy relevant part of ELF maps data to loader maps */
9fd63d05	453	for (i = 0; i < nr_maps; i++) {
74662ea5	454	struct bpf_load_map_def *def;
156450d9	455	unsigned char addr, end;
156450d9 JDB	456	const char *map_name;
	457	size_t offset;
	458
	459	map_name = elf_strptr(elf, strtabidx, sym[i].st_name);
	460	maps[i].name = strdup(map_name);
	461	if (!maps[i].name) {
9fd63d05 MKL	462	printf("strdup(%s): %s(%d)\n", map_name,
9fd63d05 MKL	463	strerror(errno), errno);
156450d9 JDB	464	free(sym);
	465	return -errno;
	466	}
	467
	468	/* Symbol value is offset into ELF maps section data area */
	469	offset = sym[i].st_value;
74662ea5	470	def = (struct bpf_load_map_def *)(data_maps->d_buf + offset);
156450d9	471	maps[i].elf_offset = offset;
74662ea5	472	memset(&maps[i].def, 0, sizeof(struct bpf_load_map_def));
156450d9 JDB	473	memcpy(&maps[i].def, def, map_sz_copy);
	474
	475	/* Verify no newer features were requested */
	476	if (validate_zero) {
	477	addr = (unsigned char*) def + map_sz_copy;
	478	end = (unsigned char*) def + map_sz_elf;
	479	for (; addr < end; addr++) {
	480	if (*addr != 0) {
	481	free(sym);
	482	return -EFBIG;
	483	}
	484	}
9fd63d05 MKL	485	}
	486	}
	487
156450d9	488	free(sym);
5010e948	489	return nr_maps;
9fd63d05 MKL	490	}
	491
	492	static int do_load_bpf_file(const char *path, fixup_map_cb fixup_map)
249b812d	493	{
9fd63d05	494	int fd, i, ret, maps_shndx = -1, strtabidx = -1;
249b812d AS	495	Elf *elf;
	496	GElf_Ehdr ehdr;
	497	GElf_Shdr shdr, shdr_prog;
9fd63d05	498	Elf_Data data, data_prog, data_maps = NULL, symbols = NULL;
156450d9 JDB	499	char shname, shname_prog;
156450d9 JDB	500	int nr_maps = 0;
249b812d	501
a734fb5d MS	502	/* reset global variables */
	503	kern_version = 0;
	504	memset(license, 0, sizeof(license));
	505	memset(processed_sec, 0, sizeof(processed_sec));
	506
249b812d AS	507	if (elf_version(EV_CURRENT) == EV_NONE)
	508	return 1;
	509
	510	fd = open(path, O_RDONLY, 0);
	511	if (fd < 0)
	512	return 1;
	513
	514	elf = elf_begin(fd, ELF_C_READ, NULL);
	515
	516	if (!elf)
	517	return 1;
	518
	519	if (gelf_getehdr(elf, &ehdr) != &ehdr)
	520	return 1;
	521
b896c4f9 AS	522	/* clear all kprobes */
	523	i = system("echo \"\" > /sys/kernel/debug/tracing/kprobe_events");
	524
249b812d AS	525	/* scan over all elf sections to get license and map info */
	526	for (i = 1; i < ehdr.e_shnum; i++) {
	527
	528	if (get_sec(elf, i, &ehdr, &shname, &shdr, &data))
	529	continue;
	530
	531	if (0) /* helpful for llvm debugging */
	532	printf("section %d:%s data %p size %zd link %d flags %d\n",
	533	i, shname, data->d_buf, data->d_size,
	534	shdr.sh_link, (int) shdr.sh_flags);
	535
	536	if (strcmp(shname, "license") == 0) {
	537	processed_sec[i] = true;
	538	memcpy(license, data->d_buf, data->d_size);
b896c4f9 AS	539	} else if (strcmp(shname, "version") == 0) {
	540	processed_sec[i] = true;
	541	if (data->d_size != sizeof(int)) {
	542	printf("invalid size of version section %zd\n",
	543	data->d_size);
	544	return 1;
	545	}
	546	memcpy(&kern_version, data->d_buf, sizeof(int));
249b812d	547	} else if (strcmp(shname, "maps") == 0) {
156450d9 JDB	548	int j;
156450d9 JDB	549
9fd63d05 MKL	550	maps_shndx = i;
9fd63d05 MKL	551	data_maps = data;
156450d9 JDB	552	for (j = 0; j < MAX_MAPS; j++)
156450d9 JDB	553	map_data[j].fd = -1;
249b812d	554	} else if (shdr.sh_type == SHT_SYMTAB) {
9fd63d05	555	strtabidx = shdr.sh_link;
249b812d AS	556	symbols = data;
	557	}
	558	}
	559
9fd63d05 MKL	560	ret = 1;
	561
	562	if (!symbols) {
	563	printf("missing SHT_SYMTAB section\n");
	564	goto done;
	565	}
	566
	567	if (data_maps) {
156450d9 JDB	568	nr_maps = load_elf_maps_section(map_data, maps_shndx,
	569	elf, symbols, strtabidx);
	570	if (nr_maps < 0) {
	571	printf("Error: Failed loading ELF maps (errno:%d):%s\n",
	572	nr_maps, strerror(-nr_maps));
5010e948 JDB	573	goto done;
5010e948 JDB	574	}
156450d9	575	if (load_maps(map_data, nr_maps, fixup_map))
9fd63d05	576	goto done;
156450d9	577	map_data_count = nr_maps;
9fd63d05 MKL	578
	579	processed_sec[maps_shndx] = true;
	580	}
	581
7bc57950	582	/* process all relo sections, and rewrite bpf insns for maps */
249b812d	583	for (i = 1; i < ehdr.e_shnum; i++) {
16ad1329 MS	584	if (processed_sec[i])
16ad1329 MS	585	continue;
249b812d AS	586
	587	if (get_sec(elf, i, &ehdr, &shname, &shdr, &data))
	588	continue;
7bc57950	589
249b812d AS	590	if (shdr.sh_type == SHT_REL) {
	591	struct bpf_insn *insns;
	592
7bc57950	593	/* locate prog sec that need map fixup (relocations) */
249b812d AS	594	if (get_sec(elf, shdr.sh_info, &ehdr, &shname_prog,
	595	&shdr_prog, &data_prog))
	596	continue;
	597
db6a71dd AS	598	if (shdr_prog.sh_type != SHT_PROGBITS \|\|
	599	!(shdr_prog.sh_flags & SHF_EXECINSTR))
	600	continue;
	601
249b812d	602	insns = (struct bpf_insn *) data_prog->d_buf;
7bc57950	603	processed_sec[i] = true; /* relo section */
249b812d	604
156450d9 JDB	605	if (parse_relo_and_apply(data, symbols, &shdr, insns,
156450d9 JDB	606	map_data, nr_maps))
249b812d	607	continue;
249b812d AS	608	}
	609	}
	610
7bc57950	611	/* load programs */
249b812d AS	612	for (i = 1; i < ehdr.e_shnum; i++) {
	613
	614	if (processed_sec[i])
	615	continue;
	616
	617	if (get_sec(elf, i, &ehdr, &shname, &shdr, &data))
	618	continue;
	619
b896c4f9 AS	620	if (memcmp(shname, "kprobe/", 7) == 0 \|\|
b896c4f9 AS	621	memcmp(shname, "kretprobe/", 10) == 0 \|\|
c0766040	622	memcmp(shname, "tracepoint/", 11) == 0 \|\|
4662a4e5	623	memcmp(shname, "raw_tracepoint/", 15) == 0 \|\|
86af8b41	624	memcmp(shname, "xdp", 3) == 0 \|\|
1c47910e	625	memcmp(shname, "perf_event", 10) == 0 \|\|
4f2e7ae5	626	memcmp(shname, "socket", 6) == 0 \|\|
40304b2a	627	memcmp(shname, "cgroup/", 7) == 0 \|\|
69e8cc13	628	memcmp(shname, "sockops", 7) == 0 \|\|
4c4c3c27 JF	629	memcmp(shname, "sk_skb", 6) == 0 \|\|
4c4c3c27 JF	630	memcmp(shname, "sk_msg", 6) == 0) {
f856e469 LB	631	ret = load_and_attach(shname, data->d_buf,
	632	data->d_size);
	633	if (ret != 0)
	634	goto done;
	635	}
249b812d AS	636	}
249b812d AS	637
9fd63d05	638	done:
249b812d	639	close(fd);
9fd63d05 MKL	640	return ret;
	641	}
	642
	643	int load_bpf_file(char *path)
	644	{
	645	return do_load_bpf_file(path, NULL);
	646	}
	647
	648	int load_bpf_file_fixup_map(const char *path, fixup_map_cb fixup_map)
	649	{
	650	return do_load_bpf_file(path, fixup_map);
249b812d	651	}
b896c4f9 AS	652
	653	void read_trace_pipe(void)
	654	{
	655	int trace_fd;
	656
	657	trace_fd = open(DEBUGFS "trace_pipe", O_RDONLY, 0);
	658	if (trace_fd < 0)
	659	return;
	660
	661	while (1) {
	662	static char buf[4096];
	663	ssize_t sz;
	664
	665	sz = read(trace_fd, buf, sizeof(buf));
	666	if (sz > 0) {
	667	buf[sz] = 0;
	668	puts(buf);
	669	}
	670	}
	671	}