This source file includes following definitions.
- oprofilefs_get_inode
- oprofilefs_str_to_user
- oprofilefs_ulong_to_user
- oprofilefs_ulong_from_user
- ulong_read_file
- ulong_write_file
- __oprofilefs_create_file
- oprofilefs_create_ulong
- oprofilefs_create_ro_ulong
- atomic_read_file
- oprofilefs_create_ro_atomic
- oprofilefs_create_file
- oprofilefs_create_file_perm
- oprofilefs_mkdir
- oprofilefs_fill_super
- oprofilefs_get_tree
- oprofilefs_init_fs_context
- oprofilefs_register
- oprofilefs_unregister
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13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/oprofile.h>
16 #include <linux/fs.h>
17 #include <linux/fs_context.h>
18 #include <linux/pagemap.h>
19 #include <linux/uaccess.h>
20
21 #include "oprof.h"
22
23 #define OPROFILEFS_MAGIC 0x6f70726f
24
25 DEFINE_RAW_SPINLOCK(oprofilefs_lock);
26
27 static struct inode *oprofilefs_get_inode(struct super_block *sb, int mode)
28 {
29 struct inode *inode = new_inode(sb);
30
31 if (inode) {
32 inode->i_ino = get_next_ino();
33 inode->i_mode = mode;
34 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
35 }
36 return inode;
37 }
38
39
40 static const struct super_operations s_ops = {
41 .statfs = simple_statfs,
42 .drop_inode = generic_delete_inode,
43 };
44
45
46 ssize_t oprofilefs_str_to_user(char const *str, char __user *buf, size_t count, loff_t *offset)
47 {
48 return simple_read_from_buffer(buf, count, offset, str, strlen(str));
49 }
50
51
52 #define TMPBUFSIZE 50
53
54 ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user *buf, size_t count, loff_t *offset)
55 {
56 char tmpbuf[TMPBUFSIZE];
57 size_t maxlen = snprintf(tmpbuf, TMPBUFSIZE, "%lu\n", val);
58 if (maxlen > TMPBUFSIZE)
59 maxlen = TMPBUFSIZE;
60 return simple_read_from_buffer(buf, count, offset, tmpbuf, maxlen);
61 }
62
63
64
65
66
67
68
69
70
71 int oprofilefs_ulong_from_user(unsigned long *val, char const __user *buf, size_t count)
72 {
73 char tmpbuf[TMPBUFSIZE];
74 unsigned long flags;
75
76 if (!count)
77 return 0;
78
79 if (count > TMPBUFSIZE - 1)
80 return -EINVAL;
81
82 memset(tmpbuf, 0x0, TMPBUFSIZE);
83
84 if (copy_from_user(tmpbuf, buf, count))
85 return -EFAULT;
86
87 raw_spin_lock_irqsave(&oprofilefs_lock, flags);
88 *val = simple_strtoul(tmpbuf, NULL, 0);
89 raw_spin_unlock_irqrestore(&oprofilefs_lock, flags);
90 return count;
91 }
92
93
94 static ssize_t ulong_read_file(struct file *file, char __user *buf, size_t count, loff_t *offset)
95 {
96 unsigned long *val = file->private_data;
97 return oprofilefs_ulong_to_user(*val, buf, count, offset);
98 }
99
100
101 static ssize_t ulong_write_file(struct file *file, char const __user *buf, size_t count, loff_t *offset)
102 {
103 unsigned long value;
104 int retval;
105
106 if (*offset)
107 return -EINVAL;
108
109 retval = oprofilefs_ulong_from_user(&value, buf, count);
110 if (retval <= 0)
111 return retval;
112
113 retval = oprofile_set_ulong(file->private_data, value);
114 if (retval)
115 return retval;
116
117 return count;
118 }
119
120
121 static const struct file_operations ulong_fops = {
122 .read = ulong_read_file,
123 .write = ulong_write_file,
124 .open = simple_open,
125 .llseek = default_llseek,
126 };
127
128
129 static const struct file_operations ulong_ro_fops = {
130 .read = ulong_read_file,
131 .open = simple_open,
132 .llseek = default_llseek,
133 };
134
135
136 static int __oprofilefs_create_file(struct dentry *root, char const *name,
137 const struct file_operations *fops, int perm, void *priv)
138 {
139 struct dentry *dentry;
140 struct inode *inode;
141
142 if (!root)
143 return -ENOMEM;
144
145 inode_lock(d_inode(root));
146 dentry = d_alloc_name(root, name);
147 if (!dentry) {
148 inode_unlock(d_inode(root));
149 return -ENOMEM;
150 }
151 inode = oprofilefs_get_inode(root->d_sb, S_IFREG | perm);
152 if (!inode) {
153 dput(dentry);
154 inode_unlock(d_inode(root));
155 return -ENOMEM;
156 }
157 inode->i_fop = fops;
158 inode->i_private = priv;
159 d_add(dentry, inode);
160 inode_unlock(d_inode(root));
161 return 0;
162 }
163
164
165 int oprofilefs_create_ulong(struct dentry *root,
166 char const *name, unsigned long *val)
167 {
168 return __oprofilefs_create_file(root, name,
169 &ulong_fops, 0644, val);
170 }
171
172
173 int oprofilefs_create_ro_ulong(struct dentry *root,
174 char const *name, unsigned long *val)
175 {
176 return __oprofilefs_create_file(root, name,
177 &ulong_ro_fops, 0444, val);
178 }
179
180
181 static ssize_t atomic_read_file(struct file *file, char __user *buf, size_t count, loff_t *offset)
182 {
183 atomic_t *val = file->private_data;
184 return oprofilefs_ulong_to_user(atomic_read(val), buf, count, offset);
185 }
186
187
188 static const struct file_operations atomic_ro_fops = {
189 .read = atomic_read_file,
190 .open = simple_open,
191 .llseek = default_llseek,
192 };
193
194
195 int oprofilefs_create_ro_atomic(struct dentry *root,
196 char const *name, atomic_t *val)
197 {
198 return __oprofilefs_create_file(root, name,
199 &atomic_ro_fops, 0444, val);
200 }
201
202
203 int oprofilefs_create_file(struct dentry *root,
204 char const *name, const struct file_operations *fops)
205 {
206 return __oprofilefs_create_file(root, name, fops, 0644, NULL);
207 }
208
209
210 int oprofilefs_create_file_perm(struct dentry *root,
211 char const *name, const struct file_operations *fops, int perm)
212 {
213 return __oprofilefs_create_file(root, name, fops, perm, NULL);
214 }
215
216
217 struct dentry *oprofilefs_mkdir(struct dentry *parent, char const *name)
218 {
219 struct dentry *dentry;
220 struct inode *inode;
221
222 inode_lock(d_inode(parent));
223 dentry = d_alloc_name(parent, name);
224 if (!dentry) {
225 inode_unlock(d_inode(parent));
226 return NULL;
227 }
228 inode = oprofilefs_get_inode(parent->d_sb, S_IFDIR | 0755);
229 if (!inode) {
230 dput(dentry);
231 inode_unlock(d_inode(parent));
232 return NULL;
233 }
234 inode->i_op = &simple_dir_inode_operations;
235 inode->i_fop = &simple_dir_operations;
236 d_add(dentry, inode);
237 inode_unlock(d_inode(parent));
238 return dentry;
239 }
240
241
242 static int oprofilefs_fill_super(struct super_block *sb, struct fs_context *fc)
243 {
244 struct inode *root_inode;
245
246 sb->s_blocksize = PAGE_SIZE;
247 sb->s_blocksize_bits = PAGE_SHIFT;
248 sb->s_magic = OPROFILEFS_MAGIC;
249 sb->s_op = &s_ops;
250 sb->s_time_gran = 1;
251
252 root_inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
253 if (!root_inode)
254 return -ENOMEM;
255 root_inode->i_op = &simple_dir_inode_operations;
256 root_inode->i_fop = &simple_dir_operations;
257 sb->s_root = d_make_root(root_inode);
258 if (!sb->s_root)
259 return -ENOMEM;
260
261 oprofile_create_files(sb->s_root);
262
263
264 return 0;
265 }
266
267 static int oprofilefs_get_tree(struct fs_context *fc)
268 {
269 return get_tree_single(fc, oprofilefs_fill_super);
270 }
271
272 static const struct fs_context_operations oprofilefs_context_ops = {
273 .get_tree = oprofilefs_get_tree,
274 };
275
276 static int oprofilefs_init_fs_context(struct fs_context *fc)
277 {
278 fc->ops = &oprofilefs_context_ops;
279 return 0;
280 }
281
282 static struct file_system_type oprofilefs_type = {
283 .owner = THIS_MODULE,
284 .name = "oprofilefs",
285 .init_fs_context = oprofilefs_init_fs_context,
286 .kill_sb = kill_litter_super,
287 };
288 MODULE_ALIAS_FS("oprofilefs");
289
290
291 int __init oprofilefs_register(void)
292 {
293 return register_filesystem(&oprofilefs_type);
294 }
295
296
297 void __exit oprofilefs_unregister(void)
298 {
299 unregister_filesystem(&oprofilefs_type);
300 }