| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | /* |
| 3 | * Provide kernel headers useful to build tracing programs |
| 4 | * such as for running eBPF tracing tools. |
| 5 | * |
| 6 | * (Borrowed code from kernel/configs.c) |
| 7 | */ |
| 8 | |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/kobject.h> |
| 12 | #include <linux/init.h> |
| 13 | |
| 14 | /* |
| 15 | * Define kernel_headers_data and kernel_headers_data_end, within which the |
| 16 | * compressed kernel headers are stored. The file is first compressed with xz. |
| 17 | */ |
| 18 | |
| 19 | asm ( |
| 20 | " .pushsection .rodata, \"a\" \n" |
| 21 | " .global kernel_headers_data \n" |
| 22 | "kernel_headers_data: \n" |
| 23 | " .incbin \"kernel/kheaders_data.tar.xz\" \n" |
| 24 | " .global kernel_headers_data_end \n" |
| 25 | "kernel_headers_data_end: \n" |
| 26 | " .popsection \n" |
| 27 | ); |
| 28 | |
| 29 | extern char kernel_headers_data[]; |
| 30 | extern char kernel_headers_data_end[]; |
| 31 | |
| 32 | static struct bin_attribute kheaders_attr __ro_after_init = |
| 33 | __BIN_ATTR_SIMPLE_RO(kheaders.tar.xz, 0444); |
| 34 | |
| 35 | static int __init ikheaders_init(void) |
| 36 | { |
| 37 | kheaders_attr.private = kernel_headers_data; |
| 38 | kheaders_attr.size = (kernel_headers_data_end - |
| 39 | kernel_headers_data); |
| 40 | return sysfs_create_bin_file(kobj: kernel_kobj, attr: &kheaders_attr); |
| 41 | } |
| 42 | |
| 43 | static void __exit ikheaders_cleanup(void) |
| 44 | { |
| 45 | sysfs_remove_bin_file(kobj: kernel_kobj, attr: &kheaders_attr); |
| 46 | } |
| 47 | |
| 48 | module_init(ikheaders_init); |
| 49 | module_exit(ikheaders_cleanup); |
| 50 | |
| 51 | MODULE_LICENSE("GPL v2"); |
| 52 | MODULE_AUTHOR("Joel Fernandes"); |
| 53 | MODULE_DESCRIPTION("Echo the kernel header artifacts used to build the kernel"); |
| 54 |