kernel/bpf/sysfs_btf.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Provide kernel BTF information for introspection and use by eBPF tools.
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/init.h>
#include <linux/sysfs.h>

/* See scripts/link-vmlinux.sh, gen_btf() func for details */
extern char __start_BTF[];
extern char __stop_BTF[];

static struct bin_attribute bin_attr_btf_vmlinux __ro_after_init = {
	.attr = { .name = "vmlinux", .mode = 0444, },
	.read_new = sysfs_bin_attr_simple_read,
};

struct kobject *btf_kobj;

static int __init btf_vmlinux_init(void)
{
	bin_attr_btf_vmlinux.private = __start_BTF;
	bin_attr_btf_vmlinux.size = __stop_BTF - __start_BTF;

	if (bin_attr_btf_vmlinux.size == 0)
		return 0;

	btf_kobj = kobject_create_and_add("btf", kernel_kobj);
	if (!btf_kobj)
		return -ENOMEM;

	return sysfs_create_bin_file(btf_kobj, &bin_attr_btf_vmlinux);
}

subsys_initcall(btf_vmlinux_init);