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