93 lines
2.2 KiB
C
93 lines
2.2 KiB
C
/*
|
|
* 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>
|
|
|
|
u64 uevent_seqnum;
|
|
char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
|
|
|
|
#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
|
|
/* current uevent sequence number */
|
|
static ssize_t uevent_seqnum_show(struct subsystem *subsys, char *page)
|
|
{
|
|
return sprintf(page, "%llu\n", (unsigned long long)uevent_seqnum);
|
|
}
|
|
KERNEL_ATTR_RO(uevent_seqnum);
|
|
|
|
/* uevent helper program, used during early boo */
|
|
static ssize_t uevent_helper_show(struct subsystem *subsys, char *page)
|
|
{
|
|
return sprintf(page, "%s\n", uevent_helper);
|
|
}
|
|
static ssize_t uevent_helper_store(struct subsystem *subsys, const char *page, size_t count)
|
|
{
|
|
if (count+1 > UEVENT_HELPER_PATH_LEN)
|
|
return -ENOENT;
|
|
memcpy(uevent_helper, page, count);
|
|
uevent_helper[count] = '\0';
|
|
if (count && uevent_helper[count-1] == '\n')
|
|
uevent_helper[count-1] = '\0';
|
|
return count;
|
|
}
|
|
KERNEL_ATTR_RW(uevent_helper);
|
|
#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
|
|
&uevent_seqnum_attr.attr,
|
|
&uevent_helper_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);
|