linux/tools/bpf/bpftool/common.c
Quentin Monnet 8f184732b6 bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects
In order to show pinned paths for BPF programs, maps, or links when
listing them with the "-f" option, bpftool creates hash maps to store
all relevant paths under the bpffs. So far, it would rely on the
kernel implementation (from tools/include/linux/hashtable.h).

We can make bpftool rely on libbpf's implementation instead. The
motivation is to make bpftool less dependent of kernel headers, to ease
the path to a potential out-of-tree mirror, like libbpf has.

This commit is the first step of the conversion: the hash maps for
pinned paths for programs, maps, and links are converted to libbpf's
hashmap.{c,h}. Other hash maps used for the PIDs of process holding
references to BPF objects are left unchanged for now. On the build side,
this requires adding a dependency to a second header internal to libbpf,
and making it a dependency for the bootstrap bpftool version as well.
The rest of the changes are a rather straightforward conversion.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211023205154.6710-4-quentin@isovalent.com
2021-10-25 17:31:38 -07:00

975 lines
19 KiB
C

// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2017-2018 Netronome Systems, Inc. */
#define _GNU_SOURCE
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <ftw.h>
#include <libgen.h>
#include <mntent.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <linux/limits.h>
#include <linux/magic.h>
#include <net/if.h>
#include <sys/mount.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/vfs.h>
#include <bpf/bpf.h>
#include <bpf/hashmap.h>
#include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
#include "main.h"
#ifndef BPF_FS_MAGIC
#define BPF_FS_MAGIC 0xcafe4a11
#endif
const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = {
[BPF_CGROUP_INET_INGRESS] = "ingress",
[BPF_CGROUP_INET_EGRESS] = "egress",
[BPF_CGROUP_INET_SOCK_CREATE] = "sock_create",
[BPF_CGROUP_INET_SOCK_RELEASE] = "sock_release",
[BPF_CGROUP_SOCK_OPS] = "sock_ops",
[BPF_CGROUP_DEVICE] = "device",
[BPF_CGROUP_INET4_BIND] = "bind4",
[BPF_CGROUP_INET6_BIND] = "bind6",
[BPF_CGROUP_INET4_CONNECT] = "connect4",
[BPF_CGROUP_INET6_CONNECT] = "connect6",
[BPF_CGROUP_INET4_POST_BIND] = "post_bind4",
[BPF_CGROUP_INET6_POST_BIND] = "post_bind6",
[BPF_CGROUP_INET4_GETPEERNAME] = "getpeername4",
[BPF_CGROUP_INET6_GETPEERNAME] = "getpeername6",
[BPF_CGROUP_INET4_GETSOCKNAME] = "getsockname4",
[BPF_CGROUP_INET6_GETSOCKNAME] = "getsockname6",
[BPF_CGROUP_UDP4_SENDMSG] = "sendmsg4",
[BPF_CGROUP_UDP6_SENDMSG] = "sendmsg6",
[BPF_CGROUP_SYSCTL] = "sysctl",
[BPF_CGROUP_UDP4_RECVMSG] = "recvmsg4",
[BPF_CGROUP_UDP6_RECVMSG] = "recvmsg6",
[BPF_CGROUP_GETSOCKOPT] = "getsockopt",
[BPF_CGROUP_SETSOCKOPT] = "setsockopt",
[BPF_SK_SKB_STREAM_PARSER] = "sk_skb_stream_parser",
[BPF_SK_SKB_STREAM_VERDICT] = "sk_skb_stream_verdict",
[BPF_SK_SKB_VERDICT] = "sk_skb_verdict",
[BPF_SK_MSG_VERDICT] = "sk_msg_verdict",
[BPF_LIRC_MODE2] = "lirc_mode2",
[BPF_FLOW_DISSECTOR] = "flow_dissector",
[BPF_TRACE_RAW_TP] = "raw_tp",
[BPF_TRACE_FENTRY] = "fentry",
[BPF_TRACE_FEXIT] = "fexit",
[BPF_MODIFY_RETURN] = "mod_ret",
[BPF_LSM_MAC] = "lsm_mac",
[BPF_SK_LOOKUP] = "sk_lookup",
[BPF_TRACE_ITER] = "trace_iter",
[BPF_XDP_DEVMAP] = "xdp_devmap",
[BPF_XDP_CPUMAP] = "xdp_cpumap",
[BPF_XDP] = "xdp",
[BPF_SK_REUSEPORT_SELECT] = "sk_skb_reuseport_select",
[BPF_SK_REUSEPORT_SELECT_OR_MIGRATE] = "sk_skb_reuseport_select_or_migrate",
};
void p_err(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
if (json_output) {
jsonw_start_object(json_wtr);
jsonw_name(json_wtr, "error");
jsonw_vprintf_enquote(json_wtr, fmt, ap);
jsonw_end_object(json_wtr);
} else {
fprintf(stderr, "Error: ");
vfprintf(stderr, fmt, ap);
fprintf(stderr, "\n");
}
va_end(ap);
}
void p_info(const char *fmt, ...)
{
va_list ap;
if (json_output)
return;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
fprintf(stderr, "\n");
va_end(ap);
}
static bool is_bpffs(char *path)
{
struct statfs st_fs;
if (statfs(path, &st_fs) < 0)
return false;
return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
}
void set_max_rlimit(void)
{
struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
setrlimit(RLIMIT_MEMLOCK, &rinf);
}
static int
mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
{
bool bind_done = false;
while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
if (errno != EINVAL || bind_done) {
snprintf(buff, bufflen,
"mount --make-private %s failed: %s",
target, strerror(errno));
return -1;
}
if (mount(target, target, "none", MS_BIND, NULL)) {
snprintf(buff, bufflen,
"mount --bind %s %s failed: %s",
target, target, strerror(errno));
return -1;
}
bind_done = true;
}
if (mount(type, target, type, 0, "mode=0700")) {
snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
type, type, target, strerror(errno));
return -1;
}
return 0;
}
int mount_tracefs(const char *target)
{
char err_str[ERR_MAX_LEN];
int err;
err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
if (err) {
err_str[ERR_MAX_LEN - 1] = '\0';
p_err("can't mount tracefs: %s", err_str);
}
return err;
}
int open_obj_pinned(const char *path, bool quiet)
{
char *pname;
int fd = -1;
pname = strdup(path);
if (!pname) {
if (!quiet)
p_err("mem alloc failed");
goto out_ret;
}
fd = bpf_obj_get(pname);
if (fd < 0) {
if (!quiet)
p_err("bpf obj get (%s): %s", pname,
errno == EACCES && !is_bpffs(dirname(pname)) ?
"directory not in bpf file system (bpffs)" :
strerror(errno));
goto out_free;
}
out_free:
free(pname);
out_ret:
return fd;
}
int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)
{
enum bpf_obj_type type;
int fd;
fd = open_obj_pinned(path, false);
if (fd < 0)
return -1;
type = get_fd_type(fd);
if (type < 0) {
close(fd);
return type;
}
if (type != exp_type) {
p_err("incorrect object type: %s", get_fd_type_name(type));
close(fd);
return -1;
}
return fd;
}
int mount_bpffs_for_pin(const char *name)
{
char err_str[ERR_MAX_LEN];
char *file;
char *dir;
int err = 0;
file = malloc(strlen(name) + 1);
if (!file) {
p_err("mem alloc failed");
return -1;
}
strcpy(file, name);
dir = dirname(file);
if (is_bpffs(dir))
/* nothing to do if already mounted */
goto out_free;
if (block_mount) {
p_err("no BPF file system found, not mounting it due to --nomount option");
err = -1;
goto out_free;
}
err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
if (err) {
err_str[ERR_MAX_LEN - 1] = '\0';
p_err("can't mount BPF file system to pin the object (%s): %s",
name, err_str);
}
out_free:
free(file);
return err;
}
int do_pin_fd(int fd, const char *name)
{
int err;
err = mount_bpffs_for_pin(name);
if (err)
return err;
err = bpf_obj_pin(fd, name);
if (err)
p_err("can't pin the object (%s): %s", name, strerror(errno));
return err;
}
int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
{
int err;
int fd;
fd = get_fd(&argc, &argv);
if (fd < 0)
return fd;
err = do_pin_fd(fd, *argv);
close(fd);
return err;
}
const char *get_fd_type_name(enum bpf_obj_type type)
{
static const char * const names[] = {
[BPF_OBJ_UNKNOWN] = "unknown",
[BPF_OBJ_PROG] = "prog",
[BPF_OBJ_MAP] = "map",
};
if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
return names[BPF_OBJ_UNKNOWN];
return names[type];
}
int get_fd_type(int fd)
{
char path[PATH_MAX];
char buf[512];
ssize_t n;
snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
n = readlink(path, buf, sizeof(buf));
if (n < 0) {
p_err("can't read link type: %s", strerror(errno));
return -1;
}
if (n == sizeof(path)) {
p_err("can't read link type: path too long!");
return -1;
}
if (strstr(buf, "bpf-map"))
return BPF_OBJ_MAP;
else if (strstr(buf, "bpf-prog"))
return BPF_OBJ_PROG;
else if (strstr(buf, "bpf-link"))
return BPF_OBJ_LINK;
return BPF_OBJ_UNKNOWN;
}
char *get_fdinfo(int fd, const char *key)
{
char path[PATH_MAX];
char *line = NULL;
size_t line_n = 0;
ssize_t n;
FILE *fdi;
snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
fdi = fopen(path, "r");
if (!fdi)
return NULL;
while ((n = getline(&line, &line_n, fdi)) > 0) {
char *value;
int len;
if (!strstr(line, key))
continue;
fclose(fdi);
value = strchr(line, '\t');
if (!value || !value[1]) {
free(line);
return NULL;
}
value++;
len = strlen(value);
memmove(line, value, len);
line[len - 1] = '\0';
return line;
}
free(line);
fclose(fdi);
return NULL;
}
void print_data_json(uint8_t *data, size_t len)
{
unsigned int i;
jsonw_start_array(json_wtr);
for (i = 0; i < len; i++)
jsonw_printf(json_wtr, "%d", data[i]);
jsonw_end_array(json_wtr);
}
void print_hex_data_json(uint8_t *data, size_t len)
{
unsigned int i;
jsonw_start_array(json_wtr);
for (i = 0; i < len; i++)
jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
jsonw_end_array(json_wtr);
}
/* extra params for nftw cb */
static struct hashmap *build_fn_table;
static enum bpf_obj_type build_fn_type;
static int do_build_table_cb(const char *fpath, const struct stat *sb,
int typeflag, struct FTW *ftwbuf)
{
struct bpf_prog_info pinned_info;
__u32 len = sizeof(pinned_info);
enum bpf_obj_type objtype;
int fd, err = 0;
char *path;
if (typeflag != FTW_F)
goto out_ret;
fd = open_obj_pinned(fpath, true);
if (fd < 0)
goto out_ret;
objtype = get_fd_type(fd);
if (objtype != build_fn_type)
goto out_close;
memset(&pinned_info, 0, sizeof(pinned_info));
if (bpf_obj_get_info_by_fd(fd, &pinned_info, &len))
goto out_close;
path = strdup(fpath);
if (!path) {
err = -1;
goto out_close;
}
err = hashmap__append(build_fn_table, u32_as_hash_field(pinned_info.id), path);
if (err) {
p_err("failed to append entry to hashmap for ID %u, path '%s': %s",
pinned_info.id, path, strerror(errno));
goto out_close;
}
out_close:
close(fd);
out_ret:
return err;
}
int build_pinned_obj_table(struct hashmap *tab,
enum bpf_obj_type type)
{
struct mntent *mntent = NULL;
FILE *mntfile = NULL;
int flags = FTW_PHYS;
int nopenfd = 16;
int err = 0;
mntfile = setmntent("/proc/mounts", "r");
if (!mntfile)
return -1;
build_fn_table = tab;
build_fn_type = type;
while ((mntent = getmntent(mntfile))) {
char *path = mntent->mnt_dir;
if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
continue;
err = nftw(path, do_build_table_cb, nopenfd, flags);
if (err)
break;
}
fclose(mntfile);
return err;
}
void delete_pinned_obj_table(struct hashmap *map)
{
struct hashmap_entry *entry;
size_t bkt;
if (!map)
return;
hashmap__for_each_entry(map, entry, bkt)
free(entry->value);
hashmap__free(map);
}
unsigned int get_page_size(void)
{
static int result;
if (!result)
result = getpagesize();
return result;
}
unsigned int get_possible_cpus(void)
{
int cpus = libbpf_num_possible_cpus();
if (cpus < 0) {
p_err("Can't get # of possible cpus: %s", strerror(-cpus));
exit(-1);
}
return cpus;
}
static char *
ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
{
struct stat st;
int err;
err = stat("/proc/self/ns/net", &st);
if (err) {
p_err("Can't stat /proc/self: %s", strerror(errno));
return NULL;
}
if (st.st_dev != ns_dev || st.st_ino != ns_ino)
return NULL;
return if_indextoname(ifindex, buf);
}
static int read_sysfs_hex_int(char *path)
{
char vendor_id_buf[8];
int len;
int fd;
fd = open(path, O_RDONLY);
if (fd < 0) {
p_err("Can't open %s: %s", path, strerror(errno));
return -1;
}
len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
close(fd);
if (len < 0) {
p_err("Can't read %s: %s", path, strerror(errno));
return -1;
}
if (len >= (int)sizeof(vendor_id_buf)) {
p_err("Value in %s too long", path);
return -1;
}
vendor_id_buf[len] = 0;
return strtol(vendor_id_buf, NULL, 0);
}
static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
{
char full_path[64];
snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
devname, entry_name);
return read_sysfs_hex_int(full_path);
}
const char *
ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
const char **opt)
{
char devname[IF_NAMESIZE];
int vendor_id;
int device_id;
if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
p_err("Can't get net device name for ifindex %d: %s", ifindex,
strerror(errno));
return NULL;
}
vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
if (vendor_id < 0) {
p_err("Can't get device vendor id for %s", devname);
return NULL;
}
switch (vendor_id) {
case 0x19ee:
device_id = read_sysfs_netdev_hex_int(devname, "device");
if (device_id != 0x4000 &&
device_id != 0x6000 &&
device_id != 0x6003)
p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
*opt = "ctx4";
return "NFP-6xxx";
default:
p_err("Can't get bfd arch name for device vendor id 0x%04x",
vendor_id);
return NULL;
}
}
void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
{
char name[IF_NAMESIZE];
if (!ifindex)
return;
printf(" offloaded_to ");
if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
printf("%s", name);
else
printf("ifindex %u ns_dev %llu ns_ino %llu",
ifindex, ns_dev, ns_inode);
}
void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
{
char name[IF_NAMESIZE];
if (!ifindex)
return;
jsonw_name(json_wtr, "dev");
jsonw_start_object(json_wtr);
jsonw_uint_field(json_wtr, "ifindex", ifindex);
jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
jsonw_string_field(json_wtr, "ifname", name);
jsonw_end_object(json_wtr);
}
int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
{
char *endptr;
NEXT_ARGP();
if (*val) {
p_err("%s already specified", what);
return -1;
}
*val = strtoul(**argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as %s", **argv, what);
return -1;
}
NEXT_ARGP();
return 0;
}
int __printf(2, 0)
print_all_levels(__maybe_unused enum libbpf_print_level level,
const char *format, va_list args)
{
return vfprintf(stderr, format, args);
}
static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
{
unsigned int id = 0;
int fd, nb_fds = 0;
void *tmp;
int err;
while (true) {
struct bpf_prog_info info = {};
__u32 len = sizeof(info);
err = bpf_prog_get_next_id(id, &id);
if (err) {
if (errno != ENOENT) {
p_err("%s", strerror(errno));
goto err_close_fds;
}
return nb_fds;
}
fd = bpf_prog_get_fd_by_id(id);
if (fd < 0) {
p_err("can't get prog by id (%u): %s",
id, strerror(errno));
goto err_close_fds;
}
err = bpf_obj_get_info_by_fd(fd, &info, &len);
if (err) {
p_err("can't get prog info (%u): %s",
id, strerror(errno));
goto err_close_fd;
}
if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) ||
(!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) {
close(fd);
continue;
}
if (nb_fds > 0) {
tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
if (!tmp) {
p_err("failed to realloc");
goto err_close_fd;
}
*fds = tmp;
}
(*fds)[nb_fds++] = fd;
}
err_close_fd:
close(fd);
err_close_fds:
while (--nb_fds >= 0)
close((*fds)[nb_fds]);
return -1;
}
int prog_parse_fds(int *argc, char ***argv, int **fds)
{
if (is_prefix(**argv, "id")) {
unsigned int id;
char *endptr;
NEXT_ARGP();
id = strtoul(**argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as ID", **argv);
return -1;
}
NEXT_ARGP();
(*fds)[0] = bpf_prog_get_fd_by_id(id);
if ((*fds)[0] < 0) {
p_err("get by id (%u): %s", id, strerror(errno));
return -1;
}
return 1;
} else if (is_prefix(**argv, "tag")) {
unsigned char tag[BPF_TAG_SIZE];
NEXT_ARGP();
if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
!= BPF_TAG_SIZE) {
p_err("can't parse tag");
return -1;
}
NEXT_ARGP();
return prog_fd_by_nametag(tag, fds, true);
} else if (is_prefix(**argv, "name")) {
char *name;
NEXT_ARGP();
name = **argv;
if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
p_err("can't parse name");
return -1;
}
NEXT_ARGP();
return prog_fd_by_nametag(name, fds, false);
} else if (is_prefix(**argv, "pinned")) {
char *path;
NEXT_ARGP();
path = **argv;
NEXT_ARGP();
(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
if ((*fds)[0] < 0)
return -1;
return 1;
}
p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
return -1;
}
int prog_parse_fd(int *argc, char ***argv)
{
int *fds = NULL;
int nb_fds, fd;
fds = malloc(sizeof(int));
if (!fds) {
p_err("mem alloc failed");
return -1;
}
nb_fds = prog_parse_fds(argc, argv, &fds);
if (nb_fds != 1) {
if (nb_fds > 1) {
p_err("several programs match this handle");
while (nb_fds--)
close(fds[nb_fds]);
}
fd = -1;
goto exit_free;
}
fd = fds[0];
exit_free:
free(fds);
return fd;
}
static int map_fd_by_name(char *name, int **fds)
{
unsigned int id = 0;
int fd, nb_fds = 0;
void *tmp;
int err;
while (true) {
struct bpf_map_info info = {};
__u32 len = sizeof(info);
err = bpf_map_get_next_id(id, &id);
if (err) {
if (errno != ENOENT) {
p_err("%s", strerror(errno));
goto err_close_fds;
}
return nb_fds;
}
fd = bpf_map_get_fd_by_id(id);
if (fd < 0) {
p_err("can't get map by id (%u): %s",
id, strerror(errno));
goto err_close_fds;
}
err = bpf_obj_get_info_by_fd(fd, &info, &len);
if (err) {
p_err("can't get map info (%u): %s",
id, strerror(errno));
goto err_close_fd;
}
if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
close(fd);
continue;
}
if (nb_fds > 0) {
tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
if (!tmp) {
p_err("failed to realloc");
goto err_close_fd;
}
*fds = tmp;
}
(*fds)[nb_fds++] = fd;
}
err_close_fd:
close(fd);
err_close_fds:
while (--nb_fds >= 0)
close((*fds)[nb_fds]);
return -1;
}
int map_parse_fds(int *argc, char ***argv, int **fds)
{
if (is_prefix(**argv, "id")) {
unsigned int id;
char *endptr;
NEXT_ARGP();
id = strtoul(**argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as ID", **argv);
return -1;
}
NEXT_ARGP();
(*fds)[0] = bpf_map_get_fd_by_id(id);
if ((*fds)[0] < 0) {
p_err("get map by id (%u): %s", id, strerror(errno));
return -1;
}
return 1;
} else if (is_prefix(**argv, "name")) {
char *name;
NEXT_ARGP();
name = **argv;
if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
p_err("can't parse name");
return -1;
}
NEXT_ARGP();
return map_fd_by_name(name, fds);
} else if (is_prefix(**argv, "pinned")) {
char *path;
NEXT_ARGP();
path = **argv;
NEXT_ARGP();
(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
if ((*fds)[0] < 0)
return -1;
return 1;
}
p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
return -1;
}
int map_parse_fd(int *argc, char ***argv)
{
int *fds = NULL;
int nb_fds, fd;
fds = malloc(sizeof(int));
if (!fds) {
p_err("mem alloc failed");
return -1;
}
nb_fds = map_parse_fds(argc, argv, &fds);
if (nb_fds != 1) {
if (nb_fds > 1) {
p_err("several maps match this handle");
while (nb_fds--)
close(fds[nb_fds]);
}
fd = -1;
goto exit_free;
}
fd = fds[0];
exit_free:
free(fds);
return fd;
}
int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
{
int err;
int fd;
fd = map_parse_fd(argc, argv);
if (fd < 0)
return -1;
err = bpf_obj_get_info_by_fd(fd, info, info_len);
if (err) {
p_err("can't get map info: %s", strerror(errno));
close(fd);
return err;
}
return fd;
}
size_t hash_fn_for_key_as_id(const void *key, void *ctx)
{
return (size_t)key;
}
bool equal_fn_for_key_as_id(const void *k1, const void *k2, void *ctx)
{
return k1 == k2;
}