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