/* * kernel/ksysfs.c - sysfs attributes in /sys/kernel, which * 		     are not related to any other subsystem * * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> *  * This file is release under the GPLv2 * */ #include <linux/config.h>#include <linux/kobject.h>#include <linux/string.h>#include <linux/sysfs.h>#include <linux/module.h>#include <linux/init.h> #define KERNEL_ATTR_RO(_name) \static struct subsys_attribute _name##_attr = __ATTR_RO(_name) #define KERNEL_ATTR_RW(_name) \static struct subsys_attribute _name##_attr = \	__ATTR(_name, 0644, _name##_show, _name##_store) #ifdef CONFIG_HOTPLUGstatic ssize_t hotplug_seqnum_show(struct subsystem *subsys, char *page){	return sprintf(page, "%llu\n", (unsigned long long)hotplug_seqnum);}KERNEL_ATTR_RO(hotplug_seqnum);#endif #ifdef CONFIG_KEXEC#include <asm/kexec.h> static ssize_t crash_notes_show(struct subsystem *subsys, char *page){	return sprintf(page, "%p\n", (void *)crash_notes);}KERNEL_ATTR_RO(crash_notes);#endif decl_subsys(kernel, NULL, NULL);EXPORT_SYMBOL_GPL(kernel_subsys); static struct attribute * kernel_attrs[] = {#ifdef CONFIG_HOTPLUG	&hotplug_seqnum_attr.attr,#endif#ifdef CONFIG_KEXEC	&crash_notes_attr.attr,#endif	NULL}; static struct attribute_group kernel_attr_group = {	.attrs = kernel_attrs,}; static int __init ksysfs_init(void){	int error = subsystem_register(&kernel_subsys);	if (!error)		error = sysfs_create_group(&kernel_subsys.kset.kobj,					   &kernel_attr_group); 	return error;} core_initcall(ksysfs_init);