/* * 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_HOTPLUG static 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);