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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
11#include <linux/kobject.h>
12#include <linux/string.h>
13#include <linux/sysfs.h>
14#include <linux/export.h>
15#include <linux/init.h>
16#include <linux/kexec.h>
17#include <linux/profile.h>
18#include <linux/stat.h>
19#include <linux/sched.h>
20#include <linux/capability.h>
21#include <linux/compiler.h>
22
23#include <linux/rcupdate.h> /* rcu_expedited */
24
25#define KERNEL_ATTR_RO(_name) \
26static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
27
28#define KERNEL_ATTR_RW(_name) \
29static struct kobj_attribute _name##_attr = \
30 __ATTR(_name, 0644, _name##_show, _name##_store)
31
32/* current uevent sequence number */
33static ssize_t uevent_seqnum_show(struct kobject *kobj,
34 struct kobj_attribute *attr, char *buf)
35{
36 return sprintf(buf, "%llu\n", (unsigned long long)uevent_seqnum);
37}
38KERNEL_ATTR_RO(uevent_seqnum);
39
40/* uevent helper program, used during early boot */
41static ssize_t uevent_helper_show(struct kobject *kobj,
42 struct kobj_attribute *attr, char *buf)
43{
44 return sprintf(buf, "%s\n", uevent_helper);
45}
46static ssize_t uevent_helper_store(struct kobject *kobj,
47 struct kobj_attribute *attr,
48 const char *buf, size_t count)
49{
50 if (count+1 > UEVENT_HELPER_PATH_LEN)
51 return -ENOENT;
52 memcpy(uevent_helper, buf, count);
53 uevent_helper[count] = '\0';
54 if (count && uevent_helper[count-1] == '\n')
55 uevent_helper[count-1] = '\0';
56 return count;
57}
58KERNEL_ATTR_RW(uevent_helper);
59
60
61#ifdef CONFIG_PROFILING
62static ssize_t profiling_show(struct kobject *kobj,
63 struct kobj_attribute *attr, char *buf)
64{
65 return sprintf(buf, "%d\n", prof_on);
66}
67static ssize_t profiling_store(struct kobject *kobj,
68 struct kobj_attribute *attr,
69 const char *buf, size_t count)
70{
71 int ret;
72
73 if (prof_on)
74 return -EEXIST;
75 /*
76 * This eventually calls into get_option() which
77 * has a ton of callers and is not const. It is
78 * easiest to cast it away here.
79 */
80 profile_setup((char *)buf);
81 ret = profile_init();
82 if (ret)
83 return ret;
84 ret = create_proc_profile();
85 if (ret)
86 return ret;
87 return count;
88}
89KERNEL_ATTR_RW(profiling);
90#endif
91
92#ifdef CONFIG_KEXEC
93static ssize_t kexec_loaded_show(struct kobject *kobj,
94 struct kobj_attribute *attr, char *buf)
95{
96 return sprintf(buf, "%d\n", !!kexec_image);
97}
98KERNEL_ATTR_RO(kexec_loaded);
99
100static ssize_t kexec_crash_loaded_show(struct kobject *kobj,
101 struct kobj_attribute *attr, char *buf)
102{
103 return sprintf(buf, "%d\n", !!kexec_crash_image);
104}
105KERNEL_ATTR_RO(kexec_crash_loaded);
106
107static ssize_t kexec_crash_size_show(struct kobject *kobj,
108 struct kobj_attribute *attr, char *buf)
109{
110 return sprintf(buf, "%zu\n", crash_get_memory_size());
111}
112static ssize_t kexec_crash_size_store(struct kobject *kobj,
113 struct kobj_attribute *attr,
114 const char *buf, size_t count)
115{
116 unsigned long cnt;
117 int ret;
118
119 if (kstrtoul(buf, 0, &cnt))
120 return -EINVAL;
121
122 ret = crash_shrink_memory(cnt);
123 return ret < 0 ? ret : count;
124}
125KERNEL_ATTR_RW(kexec_crash_size);
126
127static ssize_t vmcoreinfo_show(struct kobject *kobj,
128 struct kobj_attribute *attr, char *buf)
129{
130 return sprintf(buf, "%lx %x\n",
131 paddr_vmcoreinfo_note(),
132 (unsigned int)sizeof(vmcoreinfo_note));
133}
134KERNEL_ATTR_RO(vmcoreinfo);
135
136#endif /* CONFIG_KEXEC */
137
138/* whether file capabilities are enabled */
139static ssize_t fscaps_show(struct kobject *kobj,
140 struct kobj_attribute *attr, char *buf)
141{
142 return sprintf(buf, "%d\n", file_caps_enabled);
143}
144KERNEL_ATTR_RO(fscaps);
145
146int rcu_expedited;
147static ssize_t rcu_expedited_show(struct kobject *kobj,
148 struct kobj_attribute *attr, char *buf)
149{
150 return sprintf(buf, "%d\n", rcu_expedited);
151}
152static ssize_t rcu_expedited_store(struct kobject *kobj,
153 struct kobj_attribute *attr,
154 const char *buf, size_t count)
155{
156 if (kstrtoint(buf, 0, &rcu_expedited))
157 return -EINVAL;
158
159 return count;
160}
161KERNEL_ATTR_RW(rcu_expedited);
162
163/*
164 * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
165 */
166extern const void __start_notes __weak;
167extern const void __stop_notes __weak;
168#define notes_size (&__stop_notes - &__start_notes)
169
170static ssize_t notes_read(struct file *filp, struct kobject *kobj,
171 struct bin_attribute *bin_attr,
172 char *buf, loff_t off, size_t count)
173{
174 memcpy(buf, &__start_notes + off, count);
175 return count;
176}
177
178static struct bin_attribute notes_attr = {
179 .attr = {
180 .name = "notes",
181 .mode = S_IRUGO,
182 },
183 .read = ¬es_read,
184};
185
186struct kobject *kernel_kobj;
187EXPORT_SYMBOL_GPL(kernel_kobj);
188
189static struct attribute * kernel_attrs[] = {
190 &fscaps_attr.attr,
191 &uevent_seqnum_attr.attr,
192 &uevent_helper_attr.attr,
193#ifdef CONFIG_PROFILING
194 &profiling_attr.attr,
195#endif
196#ifdef CONFIG_KEXEC
197 &kexec_loaded_attr.attr,
198 &kexec_crash_loaded_attr.attr,
199 &kexec_crash_size_attr.attr,
200 &vmcoreinfo_attr.attr,
201#endif
202 &rcu_expedited_attr.attr,
203 NULL
204};
205
206static struct attribute_group kernel_attr_group = {
207 .attrs = kernel_attrs,
208};
209
210static int __init ksysfs_init(void)
211{
212 int error;
213
214 kernel_kobj = kobject_create_and_add("kernel", NULL);
215 if (!kernel_kobj) {
216 error = -ENOMEM;
217 goto exit;
218 }
219 error = sysfs_create_group(kernel_kobj, &kernel_attr_group);
220 if (error)
221 goto kset_exit;
222
223 if (notes_size > 0) {
224 notes_attr.size = notes_size;
225 error = sysfs_create_bin_file(kernel_kobj, ¬es_attr);
226 if (error)
227 goto group_exit;
228 }
229
230 return 0;
231
232group_exit:
233 sysfs_remove_group(kernel_kobj, &kernel_attr_group);
234kset_exit:
235 kobject_put(kernel_kobj);
236exit:
237 return error;
238}
239
240core_initcall(ksysfs_init);
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
11#include <linux/kobject.h>
12#include <linux/string.h>
13#include <linux/sysfs.h>
14#include <linux/export.h>
15#include <linux/init.h>
16#include <linux/kexec.h>
17#include <linux/profile.h>
18#include <linux/stat.h>
19#include <linux/sched.h>
20#include <linux/capability.h>
21#include <linux/compiler.h>
22
23#include <linux/rcupdate.h> /* rcu_expedited */
24
25#define KERNEL_ATTR_RO(_name) \
26static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
27
28#define KERNEL_ATTR_RW(_name) \
29static struct kobj_attribute _name##_attr = \
30 __ATTR(_name, 0644, _name##_show, _name##_store)
31
32/* current uevent sequence number */
33static ssize_t uevent_seqnum_show(struct kobject *kobj,
34 struct kobj_attribute *attr, char *buf)
35{
36 return sprintf(buf, "%llu\n", (unsigned long long)uevent_seqnum);
37}
38KERNEL_ATTR_RO(uevent_seqnum);
39
40/* uevent helper program, used during early boot */
41static ssize_t uevent_helper_show(struct kobject *kobj,
42 struct kobj_attribute *attr, char *buf)
43{
44 return sprintf(buf, "%s\n", uevent_helper);
45}
46static ssize_t uevent_helper_store(struct kobject *kobj,
47 struct kobj_attribute *attr,
48 const char *buf, size_t count)
49{
50 if (count+1 > UEVENT_HELPER_PATH_LEN)
51 return -ENOENT;
52 memcpy(uevent_helper, buf, count);
53 uevent_helper[count] = '\0';
54 if (count && uevent_helper[count-1] == '\n')
55 uevent_helper[count-1] = '\0';
56 return count;
57}
58KERNEL_ATTR_RW(uevent_helper);
59
60
61#ifdef CONFIG_PROFILING
62static ssize_t profiling_show(struct kobject *kobj,
63 struct kobj_attribute *attr, char *buf)
64{
65 return sprintf(buf, "%d\n", prof_on);
66}
67static ssize_t profiling_store(struct kobject *kobj,
68 struct kobj_attribute *attr,
69 const char *buf, size_t count)
70{
71 int ret;
72
73 if (prof_on)
74 return -EEXIST;
75 /*
76 * This eventually calls into get_option() which
77 * has a ton of callers and is not const. It is
78 * easiest to cast it away here.
79 */
80 profile_setup((char *)buf);
81 ret = profile_init();
82 if (ret)
83 return ret;
84 ret = create_proc_profile();
85 if (ret)
86 return ret;
87 return count;
88}
89KERNEL_ATTR_RW(profiling);
90#endif
91
92#ifdef CONFIG_KEXEC
93static ssize_t kexec_loaded_show(struct kobject *kobj,
94 struct kobj_attribute *attr, char *buf)
95{
96 return sprintf(buf, "%d\n", !!kexec_image);
97}
98KERNEL_ATTR_RO(kexec_loaded);
99
100static ssize_t kexec_crash_loaded_show(struct kobject *kobj,
101 struct kobj_attribute *attr, char *buf)
102{
103 return sprintf(buf, "%d\n", !!kexec_crash_image);
104}
105KERNEL_ATTR_RO(kexec_crash_loaded);
106
107static ssize_t kexec_crash_size_show(struct kobject *kobj,
108 struct kobj_attribute *attr, char *buf)
109{
110 return sprintf(buf, "%zu\n", crash_get_memory_size());
111}
112static ssize_t kexec_crash_size_store(struct kobject *kobj,
113 struct kobj_attribute *attr,
114 const char *buf, size_t count)
115{
116 unsigned long cnt;
117 int ret;
118
119 if (kstrtoul(buf, 0, &cnt))
120 return -EINVAL;
121
122 ret = crash_shrink_memory(cnt);
123 return ret < 0 ? ret : count;
124}
125KERNEL_ATTR_RW(kexec_crash_size);
126
127static ssize_t vmcoreinfo_show(struct kobject *kobj,
128 struct kobj_attribute *attr, char *buf)
129{
130 return sprintf(buf, "%lx %x\n",
131 paddr_vmcoreinfo_note(),
132 (unsigned int)sizeof(vmcoreinfo_note));
133}
134KERNEL_ATTR_RO(vmcoreinfo);
135
136#endif /* CONFIG_KEXEC */
137
138/* whether file capabilities are enabled */
139static ssize_t fscaps_show(struct kobject *kobj,
140 struct kobj_attribute *attr, char *buf)
141{
142 return sprintf(buf, "%d\n", file_caps_enabled);
143}
144KERNEL_ATTR_RO(fscaps);
145
146int rcu_expedited;
147static ssize_t rcu_expedited_show(struct kobject *kobj,
148 struct kobj_attribute *attr, char *buf)
149{
150 return sprintf(buf, "%d\n", rcu_expedited);
151}
152static ssize_t rcu_expedited_store(struct kobject *kobj,
153 struct kobj_attribute *attr,
154 const char *buf, size_t count)
155{
156 if (kstrtoint(buf, 0, &rcu_expedited))
157 return -EINVAL;
158
159 return count;
160}
161KERNEL_ATTR_RW(rcu_expedited);
162
163/*
164 * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
165 */
166extern const void __start_notes __weak;
167extern const void __stop_notes __weak;
168#define notes_size (&__stop_notes - &__start_notes)
169
170static ssize_t notes_read(struct file *filp, struct kobject *kobj,
171 struct bin_attribute *bin_attr,
172 char *buf, loff_t off, size_t count)
173{
174 memcpy(buf, &__start_notes + off, count);
175 return count;
176}
177
178static struct bin_attribute notes_attr = {
179 .attr = {
180 .name = "notes",
181 .mode = S_IRUGO,
182 },
183 .read = ¬es_read,
184};
185
186struct kobject *kernel_kobj;
187EXPORT_SYMBOL_GPL(kernel_kobj);
188
189static struct attribute * kernel_attrs[] = {
190 &fscaps_attr.attr,
191 &uevent_seqnum_attr.attr,
192 &uevent_helper_attr.attr,
193#ifdef CONFIG_PROFILING
194 &profiling_attr.attr,
195#endif
196#ifdef CONFIG_KEXEC
197 &kexec_loaded_attr.attr,
198 &kexec_crash_loaded_attr.attr,
199 &kexec_crash_size_attr.attr,
200 &vmcoreinfo_attr.attr,
201#endif
202 &rcu_expedited_attr.attr,
203 NULL
204};
205
206static struct attribute_group kernel_attr_group = {
207 .attrs = kernel_attrs,
208};
209
210static int __init ksysfs_init(void)
211{
212 int error;
213
214 kernel_kobj = kobject_create_and_add("kernel", NULL);
215 if (!kernel_kobj) {
216 error = -ENOMEM;
217 goto exit;
218 }
219 error = sysfs_create_group(kernel_kobj, &kernel_attr_group);
220 if (error)
221 goto kset_exit;
222
223 if (notes_size > 0) {
224 notes_attr.size = notes_size;
225 error = sysfs_create_bin_file(kernel_kobj, ¬es_attr);
226 if (error)
227 goto group_exit;
228 }
229
230 return 0;
231
232group_exit:
233 sysfs_remove_group(kernel_kobj, &kernel_attr_group);
234kset_exit:
235 kobject_put(kernel_kobj);
236exit:
237 return error;
238}
239
240core_initcall(ksysfs_init);