ACPI: thinkpad-acpi: wakeup on hotunplug reporting
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / kernel / ksysfs.c
blobd0e5c48e18c78c3fe1fea8a2d87d26fe4973ca2c
1 /*
2 * kernel/ksysfs.c - sysfs attributes in /sys/kernel, which
3 * are not related to any other subsystem
5 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
6 *
7 * This file is release under the GPLv2
9 */
11 #include <linux/kobject.h>
12 #include <linux/string.h>
13 #include <linux/sysfs.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/kexec.h>
18 #define KERNEL_ATTR_RO(_name) \
19 static struct subsys_attribute _name##_attr = __ATTR_RO(_name)
21 #define KERNEL_ATTR_RW(_name) \
22 static struct subsys_attribute _name##_attr = \
23 __ATTR(_name, 0644, _name##_show, _name##_store)
25 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
26 /* current uevent sequence number */
27 static ssize_t uevent_seqnum_show(struct kset *kset, char *page)
29 return sprintf(page, "%llu\n", (unsigned long long)uevent_seqnum);
31 KERNEL_ATTR_RO(uevent_seqnum);
33 /* uevent helper program, used during early boo */
34 static ssize_t uevent_helper_show(struct kset *kset, char *page)
36 return sprintf(page, "%s\n", uevent_helper);
38 static ssize_t uevent_helper_store(struct kset *kset, const char *page, size_t count)
40 if (count+1 > UEVENT_HELPER_PATH_LEN)
41 return -ENOENT;
42 memcpy(uevent_helper, page, count);
43 uevent_helper[count] = '\0';
44 if (count && uevent_helper[count-1] == '\n')
45 uevent_helper[count-1] = '\0';
46 return count;
48 KERNEL_ATTR_RW(uevent_helper);
49 #endif
51 #ifdef CONFIG_KEXEC
52 static ssize_t kexec_loaded_show(struct kset *kset, char *page)
54 return sprintf(page, "%d\n", !!kexec_image);
56 KERNEL_ATTR_RO(kexec_loaded);
58 static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page)
60 return sprintf(page, "%d\n", !!kexec_crash_image);
62 KERNEL_ATTR_RO(kexec_crash_loaded);
63 #endif /* CONFIG_KEXEC */
66 * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
68 extern const void __start_notes __attribute__((weak));
69 extern const void __stop_notes __attribute__((weak));
70 #define notes_size (&__stop_notes - &__start_notes)
72 static ssize_t notes_read(struct kobject *kobj, struct bin_attribute *bin_attr,
73 char *buf, loff_t off, size_t count)
75 memcpy(buf, &__start_notes + off, count);
76 return count;
79 static struct bin_attribute notes_attr = {
80 .attr = {
81 .name = "notes",
82 .mode = S_IRUGO,
84 .read = &notes_read,
87 decl_subsys(kernel, NULL, NULL);
88 EXPORT_SYMBOL_GPL(kernel_subsys);
90 static struct attribute * kernel_attrs[] = {
91 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
92 &uevent_seqnum_attr.attr,
93 &uevent_helper_attr.attr,
94 #endif
95 #ifdef CONFIG_KEXEC
96 &kexec_loaded_attr.attr,
97 &kexec_crash_loaded_attr.attr,
98 #endif
99 NULL
102 static struct attribute_group kernel_attr_group = {
103 .attrs = kernel_attrs,
106 static int __init ksysfs_init(void)
108 int error = subsystem_register(&kernel_subsys);
109 if (!error)
110 error = sysfs_create_group(&kernel_subsys.kobj,
111 &kernel_attr_group);
113 if (!error && notes_size > 0) {
114 notes_attr.size = notes_size;
115 error = sysfs_create_bin_file(&kernel_subsys.kobj,
116 &notes_attr);
119 return error;
122 core_initcall(ksysfs_init);