OpenCloudOS-Kernel/kernel/bpf/sysfs_btf.c

46 lines
1.1 KiB
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 __weak __start_BTF[];
extern char __weak __stop_BTF[];
static ssize_t
btf_vmlinux_read(struct file *file, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buf, loff_t off, size_t len)
{
memcpy(buf, __start_BTF + off, len);
return len;
}
static struct bin_attribute bin_attr_btf_vmlinux __ro_after_init = {
.attr = { .name = "vmlinux", .mode = 0444, },
.read = btf_vmlinux_read,
};
static struct kobject *btf_kobj;
static int __init btf_vmlinux_init(void)
{
bin_attr_btf_vmlinux.size = __stop_BTF - __start_BTF;
if (!__start_BTF || 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);