sched: cleanup: refactor normalize_rt_tasks
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / ksysfs.c
CommitLineData
1da177e4
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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
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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>
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18
19#define KERNEL_ATTR_RO(_name) \
20static struct subsys_attribute _name##_attr = __ATTR_RO(_name)
21
22#define KERNEL_ATTR_RW(_name) \
23static 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 28static 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
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32KERNEL_ATTR_RO(uevent_seqnum);
33
34/* uevent helper program, used during early boo */
823bccfc 35static ssize_t uevent_helper_show(struct kset *kset, char *page)
0f76e5ac 36{
312c004d 37 return sprintf(page, "%s\n", uevent_helper);
0f76e5ac 38}
823bccfc 39static 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';
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47 return count;
48}
49KERNEL_ATTR_RW(uevent_helper);
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50#endif
51
c330dda9 52#ifdef CONFIG_KEXEC
823bccfc 53static ssize_t kexec_loaded_show(struct kset *kset, char *page)
c330dda9
JM
54{
55 return sprintf(page, "%d\n", !!kexec_image);
56}
57KERNEL_ATTR_RO(kexec_loaded);
58
823bccfc 59static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page)
c330dda9
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60{
61 return sprintf(page, "%d\n", !!kexec_crash_image);
62}
63KERNEL_ATTR_RO(kexec_crash_loaded);
64#endif /* CONFIG_KEXEC */
65
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66/*
67 * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
68 */
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DH
69extern const void __start_notes __attribute__((weak));
70extern const void __stop_notes __attribute__((weak));
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71#define notes_size (&__stop_notes - &__start_notes)
72
73static 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
80static struct bin_attribute notes_attr = {
81 .attr = {
82 .name = "notes",
83 .mode = S_IRUGO,
84 },
85 .read = &notes_read,
86};
87
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88decl_subsys(kernel, NULL, NULL);
89EXPORT_SYMBOL_GPL(kernel_subsys);
90
91static struct attribute * kernel_attrs[] = {
f125b561 92#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
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93 &uevent_seqnum_attr.attr,
94 &uevent_helper_attr.attr,
c330dda9
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95#endif
96#ifdef CONFIG_KEXEC
97 &kexec_loaded_attr.attr,
98 &kexec_crash_loaded_attr.attr,
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99#endif
100 NULL
101};
102
103static struct attribute_group kernel_attr_group = {
104 .attrs = kernel_attrs,
105};
106
107static 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,
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112 &kernel_attr_group);
113
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114 if (!error && notes_size > 0) {
115 notes_attr.size = notes_size;
116 error = sysfs_create_bin_file(&kernel_subsys.kobj,
117 &notes_attr);
118 }
119
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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
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127 return error;
128}
129
130core_initcall(ksysfs_init);