diff options
Diffstat (limited to 'kernel/kheaders.c')
-rw-r--r-- | kernel/kheaders.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/kernel/kheaders.c b/kernel/kheaders.c new file mode 100644 index 000000000..42163c9e9 --- /dev/null +++ b/kernel/kheaders.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Provide kernel headers useful to build tracing programs + * such as for running eBPF tracing tools. + * + * (Borrowed code from kernel/configs.c) + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/kobject.h> +#include <linux/init.h> + +/* + * Define kernel_headers_data and kernel_headers_data_end, within which the + * compressed kernel headers are stored. The file is first compressed with xz. + */ + +asm ( +" .pushsection .rodata, \"a\" \n" +" .global kernel_headers_data \n" +"kernel_headers_data: \n" +" .incbin \"kernel/kheaders_data.tar.xz\" \n" +" .global kernel_headers_data_end \n" +"kernel_headers_data_end: \n" +" .popsection \n" +); + +extern char kernel_headers_data[]; +extern char kernel_headers_data_end[]; + +static ssize_t +ikheaders_read(struct file *file, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t len) +{ + memcpy(buf, &kernel_headers_data[off], len); + return len; +} + +static struct bin_attribute kheaders_attr __ro_after_init = { + .attr = { + .name = "kheaders.tar.xz", + .mode = 0444, + }, + .read = &ikheaders_read, +}; + +static int __init ikheaders_init(void) +{ + kheaders_attr.size = (kernel_headers_data_end - + kernel_headers_data); + return sysfs_create_bin_file(kernel_kobj, &kheaders_attr); +} + +static void __exit ikheaders_cleanup(void) +{ + sysfs_remove_bin_file(kernel_kobj, &kheaders_attr); +} + +module_init(ikheaders_init); +module_exit(ikheaders_cleanup); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Joel Fernandes"); +MODULE_DESCRIPTION("Echo the kernel header artifacts used to build the kernel"); |