Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * kernel/ksysfs.c - sysfs attributes in /sys/kernel, which | |
3 | * are not related to any other subsystem | |
4 | * | |
5 | * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> | |
6 | * | |
7 | * This file is release under the GPLv2 | |
8 | * | |
9 | */ | |
10 | ||
1da177e4 LT |
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> | |
c330dda9 | 16 | #include <linux/kexec.h> |
5cb350ba | 17 | #include <linux/sched.h> |
1da177e4 LT |
18 | |
19 | #define KERNEL_ATTR_RO(_name) \ | |
20 | static struct subsys_attribute _name##_attr = __ATTR_RO(_name) | |
21 | ||
22 | #define KERNEL_ATTR_RW(_name) \ | |
23 | static struct subsys_attribute _name##_attr = \ | |
24 | __ATTR(_name, 0644, _name##_show, _name##_store) | |
25 | ||
f125b561 | 26 | #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) |
0f76e5ac | 27 | /* current uevent sequence number */ |
823bccfc | 28 | static ssize_t uevent_seqnum_show(struct kset *kset, char *page) |
1da177e4 | 29 | { |
312c004d | 30 | return sprintf(page, "%llu\n", (unsigned long long)uevent_seqnum); |
1da177e4 | 31 | } |
0f76e5ac KS |
32 | KERNEL_ATTR_RO(uevent_seqnum); |
33 | ||
34 | /* uevent helper program, used during early boo */ | |
823bccfc | 35 | static ssize_t uevent_helper_show(struct kset *kset, char *page) |
0f76e5ac | 36 | { |
312c004d | 37 | return sprintf(page, "%s\n", uevent_helper); |
0f76e5ac | 38 | } |
823bccfc | 39 | static ssize_t uevent_helper_store(struct kset *kset, const char *page, size_t count) |
0f76e5ac | 40 | { |
312c004d | 41 | if (count+1 > UEVENT_HELPER_PATH_LEN) |
0f76e5ac | 42 | return -ENOENT; |
312c004d KS |
43 | memcpy(uevent_helper, page, count); |
44 | uevent_helper[count] = '\0'; | |
45 | if (count && uevent_helper[count-1] == '\n') | |
46 | uevent_helper[count-1] = '\0'; | |
0f76e5ac KS |
47 | return count; |
48 | } | |
49 | KERNEL_ATTR_RW(uevent_helper); | |
1da177e4 LT |
50 | #endif |
51 | ||
c330dda9 | 52 | #ifdef CONFIG_KEXEC |
823bccfc | 53 | static ssize_t kexec_loaded_show(struct kset *kset, char *page) |
c330dda9 JM |
54 | { |
55 | return sprintf(page, "%d\n", !!kexec_image); | |
56 | } | |
57 | KERNEL_ATTR_RO(kexec_loaded); | |
58 | ||
823bccfc | 59 | static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page) |
c330dda9 JM |
60 | { |
61 | return sprintf(page, "%d\n", !!kexec_crash_image); | |
62 | } | |
63 | KERNEL_ATTR_RO(kexec_crash_loaded); | |
64 | #endif /* CONFIG_KEXEC */ | |
65 | ||
da1a679c RM |
66 | /* |
67 | * Make /sys/kernel/notes give the raw contents of our kernel .notes section. | |
68 | */ | |
0b1937ac DH |
69 | extern const void __start_notes __attribute__((weak)); |
70 | extern const void __stop_notes __attribute__((weak)); | |
da1a679c RM |
71 | #define notes_size (&__stop_notes - &__start_notes) |
72 | ||
73 | static ssize_t notes_read(struct kobject *kobj, struct bin_attribute *bin_attr, | |
74 | char *buf, loff_t off, size_t count) | |
75 | { | |
76 | memcpy(buf, &__start_notes + off, count); | |
77 | return count; | |
78 | } | |
79 | ||
80 | static struct bin_attribute notes_attr = { | |
81 | .attr = { | |
82 | .name = "notes", | |
83 | .mode = S_IRUGO, | |
84 | }, | |
85 | .read = ¬es_read, | |
86 | }; | |
87 | ||
1da177e4 LT |
88 | decl_subsys(kernel, NULL, NULL); |
89 | EXPORT_SYMBOL_GPL(kernel_subsys); | |
90 | ||
91 | static struct attribute * kernel_attrs[] = { | |
f125b561 | 92 | #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) |
0f76e5ac KS |
93 | &uevent_seqnum_attr.attr, |
94 | &uevent_helper_attr.attr, | |
c330dda9 JM |
95 | #endif |
96 | #ifdef CONFIG_KEXEC | |
97 | &kexec_loaded_attr.attr, | |
98 | &kexec_crash_loaded_attr.attr, | |
1da177e4 LT |
99 | #endif |
100 | NULL | |
101 | }; | |
102 | ||
103 | static struct attribute_group kernel_attr_group = { | |
104 | .attrs = kernel_attrs, | |
105 | }; | |
106 | ||
107 | static int __init ksysfs_init(void) | |
108 | { | |
109 | int error = subsystem_register(&kernel_subsys); | |
110 | if (!error) | |
823bccfc | 111 | error = sysfs_create_group(&kernel_subsys.kobj, |
1da177e4 LT |
112 | &kernel_attr_group); |
113 | ||
da1a679c RM |
114 | if (!error && notes_size > 0) { |
115 | notes_attr.size = notes_size; | |
116 | error = sysfs_create_bin_file(&kernel_subsys.kobj, | |
117 | ¬es_attr); | |
118 | } | |
119 | ||
5cb350ba DG |
120 | /* |
121 | * Create "/sys/kernel/uids" directory and corresponding root user's | |
122 | * directory under it. | |
123 | */ | |
124 | if (!error) | |
125 | error = uids_kobject_init(); | |
126 | ||
1da177e4 LT |
127 | return error; |
128 | } | |
129 | ||
130 | core_initcall(ksysfs_init); |