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);

  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);