path: root/tools/bpf/bpftool/map.c

// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2017-2018 Netronome Systems, Inc. */

#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <net/if.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <bpf/bpf.h>
#include <bpf/btf.h>

#include "json_writer.h"
#include "main.h"

const char * const map_type_name[] = {
	[BPF_MAP_TYPE_UNSPEC]			= "unspec",
	[BPF_MAP_TYPE_HASH]			= "hash",
	[BPF_MAP_TYPE_ARRAY]			= "array",
	[BPF_MAP_TYPE_PROG_ARRAY]		= "prog_array",
	[BPF_MAP_TYPE_PERF_EVENT_ARRAY]		= "perf_event_array",
	[BPF_MAP_TYPE_PERCPU_HASH]		= "percpu_hash",
	[BPF_MAP_TYPE_PERCPU_ARRAY]		= "percpu_array",
	[BPF_MAP_TYPE_STACK_TRACE]		= "stack_trace",
	[BPF_MAP_TYPE_CGROUP_ARRAY]		= "cgroup_array",
	[BPF_MAP_TYPE_LRU_HASH]			= "lru_hash",
	[BPF_MAP_TYPE_LRU_PERCPU_HASH]		= "lru_percpu_hash",
	[BPF_MAP_TYPE_LPM_TRIE]			= "lpm_trie",
	[BPF_MAP_TYPE_ARRAY_OF_MAPS]		= "array_of_maps",
	[BPF_MAP_TYPE_HASH_OF_MAPS]		= "hash_of_maps",
	[BPF_MAP_TYPE_DEVMAP]			= "devmap",
	[BPF_MAP_TYPE_DEVMAP_HASH]		= "devmap_hash",
	[BPF_MAP_TYPE_SOCKMAP]			= "sockmap",
	[BPF_MAP_TYPE_CPUMAP]			= "cpumap",
	[BPF_MAP_TYPE_XSKMAP]			= "xskmap",
	[BPF_MAP_TYPE_SOCKHASH]			= "sockhash",
	[BPF_MAP_TYPE_CGROUP_STORAGE]		= "cgroup_storage",
	[BPF_MAP_TYPE_REUSEPORT_SOCKARRAY]	= "reuseport_sockarray",
	[BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE]	= "percpu_cgroup_storage",
	[BPF_MAP_TYPE_QUEUE]			= "queue",
	[BPF_MAP_TYPE_STACK]			= "stack",
	[BPF_MAP_TYPE_SK_STORAGE]		= "sk_storage",
	[BPF_MAP_TYPE_STRUCT_OPS]		= "struct_ops",
};

const size_t map_type_name_size = ARRAY_SIZE(map_type_name);

static bool map_is_per_cpu(__u32 type)
{
	return type == BPF_MAP_TYPE_PERCPU_HASH ||
	       type == BPF_MAP_TYPE_PERCPU_ARRAY ||
	       type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
	       type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE;
}

static bool map_is_map_of_maps(__u32 type)
{
	return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
	       type == BPF_MAP_TYPE_HASH_OF_MAPS;
}

static bool map_is_map_of_progs(__u32 type)
{
	return type == BPF_MAP_TYPE_PROG_ARRAY;
}

static int map_type_from_str(const char *type)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(map_type_name); i++)
		/* Don't allow prefixing in case of possible future shadowing */
		if (map_type_name[i] && !strcmp(map_type_name[i], type))
			return i;
	return -1;
}

static void *alloc_value(struct bpf_map_info *info)
{
	if (map_is_per_cpu(info->type))
		return malloc(round_up(info->value_size, 8) *
			      get_possible_cpus());
	else
		return malloc(info->value_size);
}

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)