mirror of
				git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
				synced 2025-11-01 09:13:37 +00:00 
			
		
		
		
	The kheaders archive consisting of the kernel headers used for compiling bpf programs is in /proc. However there is concern that moving it here will make it permanent. Let us move it to /sys/kernel as discussed [1]. [1] https://lore.kernel.org/patchwork/patch/1067310/#1265969 Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			66 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// 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");
 |