diff options
Diffstat (limited to 'kernel/bpf/sysfs_btf.c')
-rw-r--r-- | kernel/bpf/sysfs_btf.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/kernel/bpf/sysfs_btf.c b/kernel/bpf/sysfs_btf.c new file mode 100644 index 000000000000..7ae5dddd1fe6 --- /dev/null +++ b/kernel/bpf/sysfs_btf.c @@ -0,0 +1,46 @@ +// 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 _binary__btf_vmlinux_bin_start[]; +extern char __weak _binary__btf_vmlinux_bin_end[]; + +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, _binary__btf_vmlinux_bin_start + 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) +{ + if (!_binary__btf_vmlinux_bin_start) + return 0; + + btf_kobj = kobject_create_and_add("btf", kernel_kobj); + if (!btf_kobj) + return -ENOMEM; + + bin_attr_btf_vmlinux.size = _binary__btf_vmlinux_bin_end - + _binary__btf_vmlinux_bin_start; + + return sysfs_create_bin_file(btf_kobj, &bin_attr_btf_vmlinux); +} + +subsys_initcall(btf_vmlinux_init); |