crypto: tegra-se: fix resourse leak
[linux-3.10.git] / kernel / ksysfs.c
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) \
23 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
24
25 #define KERNEL_ATTR_RW(_name) \
26 static struct kobj_attribute _name##_attr = \
27         __ATTR(_name, 0644, _name##_show, _name##_store)
28
29 /* current uevent sequence number */
30 static 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 }
35 KERNEL_ATTR_RO(uevent_seqnum);
36
37 /* uevent helper program, used during early boot */
38 static 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 }
43 static 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 }
55 KERNEL_ATTR_RW(uevent_helper);
56
57
58 #ifdef CONFIG_PROFILING
59 static ssize_t profiling_show(struct kobject *kobj,
60                                   struct kobj_attribute *attr, char *buf)
61 {
62         return sprintf(buf, "%d\n", prof_on);
63 }
64 static 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 }
86 KERNEL_ATTR_RW(profiling);
87 #endif
88
89 #ifdef CONFIG_KEXEC
90 static 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 }
95 KERNEL_ATTR_RO(kexec_loaded);
96
97 static 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 }
102 KERNEL_ATTR_RO(kexec_crash_loaded);
103
104 static 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 }
109 static 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 }
122 KERNEL_ATTR_RW(kexec_crash_size);
123
124 static 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 }
131 KERNEL_ATTR_RO(vmcoreinfo);
132
133 #endif /* CONFIG_KEXEC */
134
135 /* whether file capabilities are enabled */
136 static 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 }
141 KERNEL_ATTR_RO(fscaps);
142
143 int rcu_expedited;
144 static ssize_t rcu_expedited_show(struct kobject *kobj,
145                                   struct kobj_attribute *attr, char *buf)
146 {
147         return sprintf(buf, "%d\n", rcu_expedited);
148 }
149 static ssize_t rcu_expedited_store(struct kobject *kobj,
150                                    struct kobj_attribute *attr,
151                                    const char *buf, size_t count)
152 {
153         if (kstrtoint(buf, 0, &rcu_expedited))
154                 return -EINVAL;
155
156         return count;
157 }
158 KERNEL_ATTR_RW(rcu_expedited);
159
160 /*
161  * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
162  */
163 extern const void __start_notes __attribute__((weak));
164 extern const void __stop_notes __attribute__((weak));
165 #define notes_size (&__stop_notes - &__start_notes)
166
167 static ssize_t notes_read(struct file *filp, struct kobject *kobj,
168                           struct bin_attribute *bin_attr,
169                           char *buf, loff_t off, size_t count)
170 {
171         memcpy(buf, &__start_notes + off, count);
172         return count;
173 }
174
175 static struct bin_attribute notes_attr = {
176         .attr = {
177                 .name = "notes",
178                 .mode = S_IRUGO,
179         },
180         .read = &notes_read,
181 };
182
183 struct kobject *kernel_kobj;
184 EXPORT_SYMBOL_GPL(kernel_kobj);
185
186 static struct attribute * kernel_attrs[] = {
187         &fscaps_attr.attr,
188         &uevent_seqnum_attr.attr,
189         &uevent_helper_attr.attr,
190 #ifdef CONFIG_PROFILING
191         &profiling_attr.attr,
192 #endif
193 #ifdef CONFIG_KEXEC
194         &kexec_loaded_attr.attr,
195         &kexec_crash_loaded_attr.attr,
196         &kexec_crash_size_attr.attr,
197         &vmcoreinfo_attr.attr,
198 #endif
199         &rcu_expedited_attr.attr,
200         NULL
201 };
202
203 static struct attribute_group kernel_attr_group = {
204         .attrs = kernel_attrs,
205 };
206
207 static int __init ksysfs_init(void)
208 {
209         int error;
210
211         kernel_kobj = kobject_create_and_add("kernel", NULL);
212         if (!kernel_kobj) {
213                 error = -ENOMEM;
214                 goto exit;
215         }
216         error = sysfs_create_group(kernel_kobj, &kernel_attr_group);
217         if (error)
218                 goto kset_exit;
219
220         if (notes_size > 0) {
221                 notes_attr.size = notes_size;
222                 error = sysfs_create_bin_file(kernel_kobj, &notes_attr);
223                 if (error)
224                         goto group_exit;
225         }
226
227         return 0;
228
229 group_exit:
230         sysfs_remove_group(kernel_kobj, &kernel_attr_group);
231 kset_exit:
232         kobject_put(kernel_kobj);
233 exit:
234         return error;
235 }
236
237 core_initcall(ksysfs_init);