Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * proc/fs/generic.c --- generic routines for the proc-fs | |
3 | * | |
4 | * This file contains generic proc-fs routines for handling | |
5 | * directories and files. | |
6 | * | |
7 | * Copyright (C) 1991, 1992 Linus Torvalds. | |
8 | * Copyright (C) 1997 Theodore Ts'o | |
9 | */ | |
10 | ||
11 | #include <linux/errno.h> | |
12 | #include <linux/time.h> | |
13 | #include <linux/proc_fs.h> | |
14 | #include <linux/stat.h> | |
1025774c | 15 | #include <linux/mm.h> |
1da177e4 | 16 | #include <linux/module.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
87ebdc00 | 18 | #include <linux/printk.h> |
1da177e4 | 19 | #include <linux/mount.h> |
1da177e4 LT |
20 | #include <linux/init.h> |
21 | #include <linux/idr.h> | |
22 | #include <linux/namei.h> | |
23 | #include <linux/bitops.h> | |
64a07bd8 | 24 | #include <linux/spinlock.h> |
786d7e16 | 25 | #include <linux/completion.h> |
1da177e4 LT |
26 | #include <asm/uaccess.h> |
27 | ||
fee781e6 AB |
28 | #include "internal.h" |
29 | ||
64a07bd8 SR |
30 | DEFINE_SPINLOCK(proc_subdir_lock); |
31 | ||
312ec7e5 | 32 | static int proc_match(unsigned int len, const char *name, struct proc_dir_entry *de) |
1da177e4 LT |
33 | { |
34 | if (de->namelen != len) | |
35 | return 0; | |
36 | return !memcmp(name, de->name, len); | |
37 | } | |
38 | ||
1da177e4 LT |
39 | /* buffer size is one page but our output routines use some slack for overruns */ |
40 | #define PROC_BLOCK_SIZE (PAGE_SIZE - 1024) | |
41 | ||
42 | static ssize_t | |
3dec7f59 | 43 | __proc_file_read(struct file *file, char __user *buf, size_t nbytes, |
1da177e4 LT |
44 | loff_t *ppos) |
45 | { | |
496ad9aa | 46 | struct inode * inode = file_inode(file); |
1da177e4 LT |
47 | char *page; |
48 | ssize_t retval=0; | |
49 | int eof=0; | |
50 | ssize_t n, count; | |
51 | char *start; | |
52 | struct proc_dir_entry * dp; | |
8b90db0d LT |
53 | unsigned long long pos; |
54 | ||
55 | /* | |
56 | * Gaah, please just use "seq_file" instead. The legacy /proc | |
57 | * interfaces cut loff_t down to off_t for reads, and ignore | |
58 | * the offset entirely for writes.. | |
59 | */ | |
60 | pos = *ppos; | |
61 | if (pos > MAX_NON_LFS) | |
62 | return 0; | |
63 | if (nbytes > MAX_NON_LFS - pos) | |
64 | nbytes = MAX_NON_LFS - pos; | |
1da177e4 LT |
65 | |
66 | dp = PDE(inode); | |
e12ba74d | 67 | if (!(page = (char*) __get_free_page(GFP_TEMPORARY))) |
1da177e4 LT |
68 | return -ENOMEM; |
69 | ||
70 | while ((nbytes > 0) && !eof) { | |
71 | count = min_t(size_t, PROC_BLOCK_SIZE, nbytes); | |
72 | ||
73 | start = NULL; | |
8731f14d | 74 | if (dp->read_proc) { |
1da177e4 LT |
75 | /* |
76 | * How to be a proc read function | |
77 | * ------------------------------ | |
78 | * Prototype: | |
79 | * int f(char *buffer, char **start, off_t offset, | |
80 | * int count, int *peof, void *dat) | |
81 | * | |
82 | * Assume that the buffer is "count" bytes in size. | |
83 | * | |
84 | * If you know you have supplied all the data you | |
85 | * have, set *peof. | |
86 | * | |
87 | * You have three ways to return data: | |
88 | * 0) Leave *start = NULL. (This is the default.) | |
89 | * Put the data of the requested offset at that | |
90 | * offset within the buffer. Return the number (n) | |
91 | * of bytes there are from the beginning of the | |
92 | * buffer up to the last byte of data. If the | |
93 | * number of supplied bytes (= n - offset) is | |
94 | * greater than zero and you didn't signal eof | |
95 | * and the reader is prepared to take more data | |
96 | * you will be called again with the requested | |
97 | * offset advanced by the number of bytes | |
98 | * absorbed. This interface is useful for files | |
99 | * no larger than the buffer. | |
100 | * 1) Set *start = an unsigned long value less than | |
101 | * the buffer address but greater than zero. | |
102 | * Put the data of the requested offset at the | |
103 | * beginning of the buffer. Return the number of | |
104 | * bytes of data placed there. If this number is | |
105 | * greater than zero and you didn't signal eof | |
106 | * and the reader is prepared to take more data | |
107 | * you will be called again with the requested | |
108 | * offset advanced by *start. This interface is | |
109 | * useful when you have a large file consisting | |
110 | * of a series of blocks which you want to count | |
111 | * and return as wholes. | |
112 | * (Hack by Paul.Russell@rustcorp.com.au) | |
113 | * 2) Set *start = an address within the buffer. | |
114 | * Put the data of the requested offset at *start. | |
115 | * Return the number of bytes of data placed there. | |
116 | * If this number is greater than zero and you | |
117 | * didn't signal eof and the reader is prepared to | |
118 | * take more data you will be called again with the | |
119 | * requested offset advanced by the number of bytes | |
120 | * absorbed. | |
121 | */ | |
122 | n = dp->read_proc(page, &start, *ppos, | |
123 | count, &eof, dp->data); | |
124 | } else | |
125 | break; | |
126 | ||
127 | if (n == 0) /* end of file */ | |
128 | break; | |
129 | if (n < 0) { /* error */ | |
130 | if (retval == 0) | |
131 | retval = n; | |
132 | break; | |
133 | } | |
134 | ||
135 | if (start == NULL) { | |
87ebdc00 | 136 | if (n > PAGE_SIZE) /* Apparent buffer overflow */ |
1da177e4 | 137 | n = PAGE_SIZE; |
1da177e4 LT |
138 | n -= *ppos; |
139 | if (n <= 0) | |
140 | break; | |
141 | if (n > count) | |
142 | n = count; | |
143 | start = page + *ppos; | |
144 | } else if (start < page) { | |
87ebdc00 | 145 | if (n > PAGE_SIZE) /* Apparent buffer overflow */ |
1da177e4 | 146 | n = PAGE_SIZE; |
1da177e4 LT |
147 | if (n > count) { |
148 | /* | |
149 | * Don't reduce n because doing so might | |
150 | * cut off part of a data block. | |
151 | */ | |
87ebdc00 | 152 | pr_warn("proc_file_read: count exceeded\n"); |
1da177e4 LT |
153 | } |
154 | } else /* start >= page */ { | |
155 | unsigned long startoff = (unsigned long)(start - page); | |
87ebdc00 | 156 | if (n > (PAGE_SIZE - startoff)) /* buffer overflow? */ |
1da177e4 | 157 | n = PAGE_SIZE - startoff; |
1da177e4 LT |
158 | if (n > count) |
159 | n = count; | |
160 | } | |
161 | ||
162 | n -= copy_to_user(buf, start < page ? page : start, n); | |
163 | if (n == 0) { | |
164 | if (retval == 0) | |
165 | retval = -EFAULT; | |
166 | break; | |
167 | } | |
168 | ||
169 | *ppos += start < page ? (unsigned long)start : n; | |
170 | nbytes -= n; | |
171 | buf += n; | |
172 | retval += n; | |
173 | } | |
174 | free_page((unsigned long) page); | |
175 | return retval; | |
176 | } | |
177 | ||
3dec7f59 AD |
178 | static ssize_t |
179 | proc_file_read(struct file *file, char __user *buf, size_t nbytes, | |
180 | loff_t *ppos) | |
181 | { | |
496ad9aa | 182 | struct proc_dir_entry *pde = PDE(file_inode(file)); |
3dec7f59 AD |
183 | ssize_t rv = -EIO; |
184 | ||
185 | spin_lock(&pde->pde_unload_lock); | |
186 | if (!pde->proc_fops) { | |
187 | spin_unlock(&pde->pde_unload_lock); | |
188 | return rv; | |
189 | } | |
190 | pde->pde_users++; | |
191 | spin_unlock(&pde->pde_unload_lock); | |
192 | ||
193 | rv = __proc_file_read(file, buf, nbytes, ppos); | |
194 | ||
195 | pde_users_dec(pde); | |
196 | return rv; | |
197 | } | |
198 | ||
1da177e4 LT |
199 | static loff_t |
200 | proc_file_lseek(struct file *file, loff_t offset, int orig) | |
201 | { | |
8b90db0d LT |
202 | loff_t retval = -EINVAL; |
203 | switch (orig) { | |
204 | case 1: | |
205 | offset += file->f_pos; | |
206 | /* fallthrough */ | |
207 | case 0: | |
208 | if (offset < 0 || offset > MAX_NON_LFS) | |
209 | break; | |
210 | file->f_pos = retval = offset; | |
211 | } | |
212 | return retval; | |
1da177e4 LT |
213 | } |
214 | ||
76df0c25 AD |
215 | static const struct file_operations proc_file_operations = { |
216 | .llseek = proc_file_lseek, | |
217 | .read = proc_file_read, | |
76df0c25 AD |
218 | }; |
219 | ||
1da177e4 LT |
220 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) |
221 | { | |
222 | struct inode *inode = dentry->d_inode; | |
223 | struct proc_dir_entry *de = PDE(inode); | |
224 | int error; | |
225 | ||
226 | error = inode_change_ok(inode, iattr); | |
227 | if (error) | |
1025774c | 228 | return error; |
1da177e4 | 229 | |
1025774c CH |
230 | setattr_copy(inode, iattr); |
231 | mark_inode_dirty(inode); | |
46f69557 | 232 | |
1da177e4 LT |
233 | de->uid = inode->i_uid; |
234 | de->gid = inode->i_gid; | |
235 | de->mode = inode->i_mode; | |
1025774c | 236 | return 0; |
1da177e4 LT |
237 | } |
238 | ||
2b579bee MS |
239 | static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry, |
240 | struct kstat *stat) | |
241 | { | |
242 | struct inode *inode = dentry->d_inode; | |
243 | struct proc_dir_entry *de = PROC_I(inode)->pde; | |
244 | if (de && de->nlink) | |
bfe86848 | 245 | set_nlink(inode, de->nlink); |
2b579bee MS |
246 | |
247 | generic_fillattr(inode, stat); | |
248 | return 0; | |
249 | } | |
250 | ||
c5ef1c42 | 251 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
252 | .setattr = proc_notify_change, |
253 | }; | |
254 | ||
255 | /* | |
256 | * This function parses a name such as "tty/driver/serial", and | |
257 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
258 | * returns "serial" in residual. | |
259 | */ | |
e17a5765 AD |
260 | static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret, |
261 | const char **residual) | |
1da177e4 LT |
262 | { |
263 | const char *cp = name, *next; | |
264 | struct proc_dir_entry *de; | |
312ec7e5 | 265 | unsigned int len; |
1da177e4 | 266 | |
7cee4e00 AD |
267 | de = *ret; |
268 | if (!de) | |
269 | de = &proc_root; | |
270 | ||
1da177e4 LT |
271 | while (1) { |
272 | next = strchr(cp, '/'); | |
273 | if (!next) | |
274 | break; | |
275 | ||
276 | len = next - cp; | |
277 | for (de = de->subdir; de ; de = de->next) { | |
278 | if (proc_match(len, cp, de)) | |
279 | break; | |
280 | } | |
12bac0d9 AD |
281 | if (!de) { |
282 | WARN(1, "name '%s'\n", name); | |
e17a5765 | 283 | return -ENOENT; |
12bac0d9 | 284 | } |
1da177e4 LT |
285 | cp += len + 1; |
286 | } | |
287 | *residual = cp; | |
288 | *ret = de; | |
e17a5765 AD |
289 | return 0; |
290 | } | |
291 | ||
292 | static int xlate_proc_name(const char *name, struct proc_dir_entry **ret, | |
293 | const char **residual) | |
294 | { | |
295 | int rv; | |
296 | ||
297 | spin_lock(&proc_subdir_lock); | |
298 | rv = __xlate_proc_name(name, ret, residual); | |
64a07bd8 | 299 | spin_unlock(&proc_subdir_lock); |
e17a5765 | 300 | return rv; |
1da177e4 LT |
301 | } |
302 | ||
9a185409 | 303 | static DEFINE_IDA(proc_inum_ida); |
1da177e4 LT |
304 | static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ |
305 | ||
67935df4 | 306 | #define PROC_DYNAMIC_FIRST 0xF0000000U |
1da177e4 LT |
307 | |
308 | /* | |
309 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
310 | * 0xffffffff, or zero on failure. | |
311 | */ | |
33d6dce6 | 312 | int proc_alloc_inum(unsigned int *inum) |
1da177e4 | 313 | { |
67935df4 | 314 | unsigned int i; |
1da177e4 LT |
315 | int error; |
316 | ||
317 | retry: | |
33d6dce6 EB |
318 | if (!ida_pre_get(&proc_inum_ida, GFP_KERNEL)) |
319 | return -ENOMEM; | |
1da177e4 | 320 | |
dfb2ea45 | 321 | spin_lock_irq(&proc_inum_lock); |
9a185409 | 322 | error = ida_get_new(&proc_inum_ida, &i); |
dfb2ea45 | 323 | spin_unlock_irq(&proc_inum_lock); |
1da177e4 LT |
324 | if (error == -EAGAIN) |
325 | goto retry; | |
326 | else if (error) | |
33d6dce6 | 327 | return error; |
1da177e4 | 328 | |
67935df4 | 329 | if (i > UINT_MAX - PROC_DYNAMIC_FIRST) { |
dfb2ea45 | 330 | spin_lock_irq(&proc_inum_lock); |
9a185409 | 331 | ida_remove(&proc_inum_ida, i); |
dfb2ea45 | 332 | spin_unlock_irq(&proc_inum_lock); |
33d6dce6 | 333 | return -ENOSPC; |
67935df4 | 334 | } |
33d6dce6 EB |
335 | *inum = PROC_DYNAMIC_FIRST + i; |
336 | return 0; | |
1da177e4 LT |
337 | } |
338 | ||
33d6dce6 | 339 | void proc_free_inum(unsigned int inum) |
1da177e4 | 340 | { |
dfb2ea45 EB |
341 | unsigned long flags; |
342 | spin_lock_irqsave(&proc_inum_lock, flags); | |
9a185409 | 343 | ida_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); |
dfb2ea45 | 344 | spin_unlock_irqrestore(&proc_inum_lock, flags); |
1da177e4 LT |
345 | } |
346 | ||
008b150a | 347 | static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 | 348 | { |
d9dda78b | 349 | nd_set_link(nd, PDE_DATA(dentry->d_inode)); |
008b150a | 350 | return NULL; |
1da177e4 LT |
351 | } |
352 | ||
c5ef1c42 | 353 | static const struct inode_operations proc_link_inode_operations = { |
1da177e4 LT |
354 | .readlink = generic_readlink, |
355 | .follow_link = proc_follow_link, | |
356 | }; | |
357 | ||
358 | /* | |
359 | * As some entries in /proc are volatile, we want to | |
360 | * get rid of unused dentries. This could be made | |
361 | * smarter: we could keep a "volatile" flag in the | |
362 | * inode to indicate which ones to keep. | |
363 | */ | |
fe15ce44 | 364 | static int proc_delete_dentry(const struct dentry * dentry) |
1da177e4 LT |
365 | { |
366 | return 1; | |
367 | } | |
368 | ||
d72f71eb | 369 | static const struct dentry_operations proc_dentry_operations = |
1da177e4 LT |
370 | { |
371 | .d_delete = proc_delete_dentry, | |
372 | }; | |
373 | ||
374 | /* | |
375 | * Don't create negative dentries here, return -ENOENT by hand | |
376 | * instead. | |
377 | */ | |
e9720acd PE |
378 | struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir, |
379 | struct dentry *dentry) | |
1da177e4 | 380 | { |
d3d009cb | 381 | struct inode *inode; |
1da177e4 | 382 | |
64a07bd8 | 383 | spin_lock(&proc_subdir_lock); |
5e971dce AD |
384 | for (de = de->subdir; de ; de = de->next) { |
385 | if (de->namelen != dentry->d_name.len) | |
386 | continue; | |
387 | if (!memcmp(dentry->d_name.name, de->name, de->namelen)) { | |
135d5655 | 388 | pde_get(de); |
5e971dce | 389 | spin_unlock(&proc_subdir_lock); |
6d1b6e4e | 390 | inode = proc_get_inode(dir->i_sb, de); |
d3d009cb AV |
391 | if (!inode) |
392 | return ERR_PTR(-ENOMEM); | |
393 | d_set_d_op(dentry, &proc_dentry_operations); | |
394 | d_add(dentry, inode); | |
395 | return NULL; | |
1da177e4 LT |
396 | } |
397 | } | |
64a07bd8 | 398 | spin_unlock(&proc_subdir_lock); |
d3d009cb | 399 | return ERR_PTR(-ENOENT); |
1da177e4 LT |
400 | } |
401 | ||
e9720acd | 402 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 403 | unsigned int flags) |
e9720acd PE |
404 | { |
405 | return proc_lookup_de(PDE(dir), dir, dentry); | |
406 | } | |
407 | ||
1da177e4 LT |
408 | /* |
409 | * This returns non-zero if at EOF, so that the /proc | |
410 | * root directory can use this and check if it should | |
411 | * continue with the <pid> entries.. | |
412 | * | |
413 | * Note that the VFS-layer doesn't care about the return | |
414 | * value of the readdir() call, as long as it's non-negative | |
415 | * for success.. | |
416 | */ | |
e9720acd PE |
417 | int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent, |
418 | filldir_t filldir) | |
1da177e4 | 419 | { |
1da177e4 LT |
420 | unsigned int ino; |
421 | int i; | |
496ad9aa | 422 | struct inode *inode = file_inode(filp); |
1da177e4 LT |
423 | int ret = 0; |
424 | ||
1da177e4 | 425 | ino = inode->i_ino; |
1da177e4 LT |
426 | i = filp->f_pos; |
427 | switch (i) { | |
428 | case 0: | |
429 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
430 | goto out; | |
431 | i++; | |
432 | filp->f_pos++; | |
433 | /* fall through */ | |
434 | case 1: | |
435 | if (filldir(dirent, "..", 2, i, | |
2fddfeef | 436 | parent_ino(filp->f_path.dentry), |
1da177e4 LT |
437 | DT_DIR) < 0) |
438 | goto out; | |
439 | i++; | |
440 | filp->f_pos++; | |
441 | /* fall through */ | |
442 | default: | |
64a07bd8 | 443 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
444 | de = de->subdir; |
445 | i -= 2; | |
446 | for (;;) { | |
447 | if (!de) { | |
448 | ret = 1; | |
64a07bd8 | 449 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
450 | goto out; |
451 | } | |
452 | if (!i) | |
453 | break; | |
454 | de = de->next; | |
455 | i--; | |
456 | } | |
457 | ||
458 | do { | |
59cd0cbc DW |
459 | struct proc_dir_entry *next; |
460 | ||
64a07bd8 | 461 | /* filldir passes info to user space */ |
135d5655 | 462 | pde_get(de); |
64a07bd8 | 463 | spin_unlock(&proc_subdir_lock); |
1da177e4 | 464 | if (filldir(dirent, de->name, de->namelen, filp->f_pos, |
59cd0cbc | 465 | de->low_ino, de->mode >> 12) < 0) { |
135d5655 | 466 | pde_put(de); |
1da177e4 | 467 | goto out; |
59cd0cbc | 468 | } |
64a07bd8 | 469 | spin_lock(&proc_subdir_lock); |
1da177e4 | 470 | filp->f_pos++; |
59cd0cbc | 471 | next = de->next; |
135d5655 | 472 | pde_put(de); |
59cd0cbc | 473 | de = next; |
1da177e4 | 474 | } while (de); |
64a07bd8 | 475 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
476 | } |
477 | ret = 1; | |
b4df2b92 | 478 | out: |
1da177e4 LT |
479 | return ret; |
480 | } | |
481 | ||
e9720acd PE |
482 | int proc_readdir(struct file *filp, void *dirent, filldir_t filldir) |
483 | { | |
496ad9aa | 484 | struct inode *inode = file_inode(filp); |
e9720acd PE |
485 | |
486 | return proc_readdir_de(PDE(inode), filp, dirent, filldir); | |
487 | } | |
488 | ||
1da177e4 LT |
489 | /* |
490 | * These are the generic /proc directory operations. They | |
491 | * use the in-memory "struct proc_dir_entry" tree to parse | |
492 | * the /proc directory. | |
493 | */ | |
00977a59 | 494 | static const struct file_operations proc_dir_operations = { |
b4df2b92 | 495 | .llseek = generic_file_llseek, |
1da177e4 LT |
496 | .read = generic_read_dir, |
497 | .readdir = proc_readdir, | |
498 | }; | |
499 | ||
500 | /* | |
501 | * proc directories can do almost nothing.. | |
502 | */ | |
c5ef1c42 | 503 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 504 | .lookup = proc_lookup, |
2b579bee | 505 | .getattr = proc_getattr, |
1da177e4 LT |
506 | .setattr = proc_notify_change, |
507 | }; | |
508 | ||
509 | static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) | |
510 | { | |
94413d88 | 511 | struct proc_dir_entry *tmp; |
33d6dce6 | 512 | int ret; |
1da177e4 | 513 | |
33d6dce6 EB |
514 | ret = proc_alloc_inum(&dp->low_ino); |
515 | if (ret) | |
516 | return ret; | |
64a07bd8 | 517 | |
1da177e4 | 518 | if (S_ISDIR(dp->mode)) { |
b6cdc731 AV |
519 | dp->proc_fops = &proc_dir_operations; |
520 | dp->proc_iops = &proc_dir_inode_operations; | |
1da177e4 LT |
521 | dir->nlink++; |
522 | } else if (S_ISLNK(dp->mode)) { | |
b6cdc731 | 523 | dp->proc_iops = &proc_link_inode_operations; |
1da177e4 LT |
524 | } else if (S_ISREG(dp->mode)) { |
525 | if (dp->proc_fops == NULL) | |
526 | dp->proc_fops = &proc_file_operations; | |
b6cdc731 AV |
527 | dp->proc_iops = &proc_file_inode_operations; |
528 | } else { | |
529 | WARN_ON(1); | |
530 | return -EINVAL; | |
1da177e4 | 531 | } |
99fc06df CG |
532 | |
533 | spin_lock(&proc_subdir_lock); | |
94413d88 ZR |
534 | |
535 | for (tmp = dir->subdir; tmp; tmp = tmp->next) | |
536 | if (strcmp(tmp->name, dp->name) == 0) { | |
87ebdc00 | 537 | WARN(1, "proc_dir_entry '%s/%s' already registered\n", |
665020c3 | 538 | dir->name, dp->name); |
94413d88 ZR |
539 | break; |
540 | } | |
541 | ||
99fc06df CG |
542 | dp->next = dir->subdir; |
543 | dp->parent = dir; | |
544 | dir->subdir = dp; | |
545 | spin_unlock(&proc_subdir_lock); | |
546 | ||
1da177e4 LT |
547 | return 0; |
548 | } | |
549 | ||
2d3a4e36 | 550 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 | 551 | const char *name, |
d161a13f | 552 | umode_t mode, |
1da177e4 LT |
553 | nlink_t nlink) |
554 | { | |
555 | struct proc_dir_entry *ent = NULL; | |
556 | const char *fn = name; | |
312ec7e5 | 557 | unsigned int len; |
1da177e4 LT |
558 | |
559 | /* make sure name is valid */ | |
17baa2a2 | 560 | if (!name || !strlen(name)) |
561 | goto out; | |
1da177e4 | 562 | |
7cee4e00 | 563 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 LT |
564 | goto out; |
565 | ||
566 | /* At this point there must not be any '/' characters beyond *fn */ | |
567 | if (strchr(fn, '/')) | |
568 | goto out; | |
569 | ||
570 | len = strlen(fn); | |
571 | ||
17baa2a2 | 572 | ent = kzalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL); |
573 | if (!ent) | |
574 | goto out; | |
1da177e4 | 575 | |
09570f91 | 576 | memcpy(ent->name, fn, len + 1); |
1da177e4 LT |
577 | ent->namelen = len; |
578 | ent->mode = mode; | |
579 | ent->nlink = nlink; | |
5a622f2d | 580 | atomic_set(&ent->count, 1); |
786d7e16 | 581 | spin_lock_init(&ent->pde_unload_lock); |
881adb85 | 582 | INIT_LIST_HEAD(&ent->pde_openers); |
17baa2a2 | 583 | out: |
1da177e4 LT |
584 | return ent; |
585 | } | |
586 | ||
587 | struct proc_dir_entry *proc_symlink(const char *name, | |
588 | struct proc_dir_entry *parent, const char *dest) | |
589 | { | |
590 | struct proc_dir_entry *ent; | |
591 | ||
2d3a4e36 | 592 | ent = __proc_create(&parent, name, |
1da177e4 LT |
593 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
594 | ||
595 | if (ent) { | |
596 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
597 | if (ent->data) { | |
598 | strcpy((char*)ent->data,dest); | |
599 | if (proc_register(parent, ent) < 0) { | |
600 | kfree(ent->data); | |
601 | kfree(ent); | |
602 | ent = NULL; | |
603 | } | |
604 | } else { | |
605 | kfree(ent); | |
606 | ent = NULL; | |
607 | } | |
608 | } | |
609 | return ent; | |
610 | } | |
587d4a17 | 611 | EXPORT_SYMBOL(proc_symlink); |
1da177e4 | 612 | |
d161a13f | 613 | struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode, |
1da177e4 LT |
614 | struct proc_dir_entry *parent) |
615 | { | |
616 | struct proc_dir_entry *ent; | |
617 | ||
2d3a4e36 | 618 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 619 | if (ent) { |
1da177e4 LT |
620 | if (proc_register(parent, ent) < 0) { |
621 | kfree(ent); | |
622 | ent = NULL; | |
623 | } | |
624 | } | |
625 | return ent; | |
626 | } | |
011159a0 | 627 | EXPORT_SYMBOL(proc_mkdir_mode); |
1da177e4 | 628 | |
78e92b99 DL |
629 | struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name, |
630 | struct proc_dir_entry *parent) | |
631 | { | |
632 | struct proc_dir_entry *ent; | |
633 | ||
634 | ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2); | |
635 | if (ent) { | |
636 | ent->data = net; | |
637 | if (proc_register(parent, ent) < 0) { | |
638 | kfree(ent); | |
639 | ent = NULL; | |
640 | } | |
641 | } | |
642 | return ent; | |
643 | } | |
644 | EXPORT_SYMBOL_GPL(proc_net_mkdir); | |
645 | ||
1da177e4 LT |
646 | struct proc_dir_entry *proc_mkdir(const char *name, |
647 | struct proc_dir_entry *parent) | |
648 | { | |
649 | return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); | |
650 | } | |
587d4a17 | 651 | EXPORT_SYMBOL(proc_mkdir); |
1da177e4 | 652 | |
d161a13f | 653 | struct proc_dir_entry *create_proc_entry(const char *name, umode_t mode, |
1da177e4 LT |
654 | struct proc_dir_entry *parent) |
655 | { | |
656 | struct proc_dir_entry *ent; | |
1da177e4 | 657 | |
b6cdc731 AV |
658 | if ((mode & S_IFMT) == 0) |
659 | mode |= S_IFREG; | |
660 | ||
661 | if (!S_ISREG(mode)) { | |
662 | WARN_ON(1); /* use proc_mkdir(), damnit */ | |
663 | return NULL; | |
1da177e4 LT |
664 | } |
665 | ||
b6cdc731 AV |
666 | if ((mode & S_IALLUGO) == 0) |
667 | mode |= S_IRUGO; | |
668 | ||
669 | ent = __proc_create(&parent, name, mode, 1); | |
1da177e4 | 670 | if (ent) { |
1da177e4 LT |
671 | if (proc_register(parent, ent) < 0) { |
672 | kfree(ent); | |
673 | ent = NULL; | |
674 | } | |
675 | } | |
676 | return ent; | |
677 | } | |
587d4a17 | 678 | EXPORT_SYMBOL(create_proc_entry); |
1da177e4 | 679 | |
d161a13f | 680 | struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, |
59b74351 DL |
681 | struct proc_dir_entry *parent, |
682 | const struct file_operations *proc_fops, | |
683 | void *data) | |
2d3a4e36 AD |
684 | { |
685 | struct proc_dir_entry *pde; | |
b6cdc731 AV |
686 | if ((mode & S_IFMT) == 0) |
687 | mode |= S_IFREG; | |
2d3a4e36 | 688 | |
b6cdc731 AV |
689 | if (!S_ISREG(mode)) { |
690 | WARN_ON(1); /* use proc_mkdir() */ | |
691 | return NULL; | |
2d3a4e36 AD |
692 | } |
693 | ||
b6cdc731 AV |
694 | if ((mode & S_IALLUGO) == 0) |
695 | mode |= S_IRUGO; | |
696 | pde = __proc_create(&parent, name, mode, 1); | |
2d3a4e36 AD |
697 | if (!pde) |
698 | goto out; | |
699 | pde->proc_fops = proc_fops; | |
59b74351 | 700 | pde->data = data; |
2d3a4e36 AD |
701 | if (proc_register(parent, pde) < 0) |
702 | goto out_free; | |
703 | return pde; | |
704 | out_free: | |
705 | kfree(pde); | |
706 | out: | |
707 | return NULL; | |
708 | } | |
587d4a17 | 709 | EXPORT_SYMBOL(proc_create_data); |
2d3a4e36 | 710 | |
135d5655 | 711 | static void free_proc_entry(struct proc_dir_entry *de) |
1da177e4 | 712 | { |
33d6dce6 | 713 | proc_free_inum(de->low_ino); |
1da177e4 | 714 | |
fd2cbe48 | 715 | if (S_ISLNK(de->mode)) |
1da177e4 LT |
716 | kfree(de->data); |
717 | kfree(de); | |
718 | } | |
719 | ||
135d5655 AD |
720 | void pde_put(struct proc_dir_entry *pde) |
721 | { | |
722 | if (atomic_dec_and_test(&pde->count)) | |
723 | free_proc_entry(pde); | |
724 | } | |
725 | ||
8ce584c7 | 726 | static void entry_rundown(struct proc_dir_entry *de) |
1da177e4 | 727 | { |
f649d6d3 AD |
728 | spin_lock(&de->pde_unload_lock); |
729 | /* | |
730 | * Stop accepting new callers into module. If you're | |
731 | * dynamically allocating ->proc_fops, save a pointer somewhere. | |
732 | */ | |
733 | de->proc_fops = NULL; | |
734 | /* Wait until all existing callers into module are done. */ | |
735 | if (de->pde_users > 0) { | |
736 | DECLARE_COMPLETION_ONSTACK(c); | |
737 | ||
738 | if (!de->pde_unload_completion) | |
739 | de->pde_unload_completion = &c; | |
786d7e16 | 740 | |
786d7e16 AD |
741 | spin_unlock(&de->pde_unload_lock); |
742 | ||
f649d6d3 AD |
743 | wait_for_completion(de->pde_unload_completion); |
744 | ||
3740a20c | 745 | spin_lock(&de->pde_unload_lock); |
f649d6d3 | 746 | } |
f649d6d3 | 747 | |
881adb85 AD |
748 | while (!list_empty(&de->pde_openers)) { |
749 | struct pde_opener *pdeo; | |
750 | ||
751 | pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh); | |
752 | list_del(&pdeo->lh); | |
753 | spin_unlock(&de->pde_unload_lock); | |
754 | pdeo->release(pdeo->inode, pdeo->file); | |
755 | kfree(pdeo); | |
756 | spin_lock(&de->pde_unload_lock); | |
757 | } | |
758 | spin_unlock(&de->pde_unload_lock); | |
8ce584c7 AV |
759 | } |
760 | ||
761 | /* | |
762 | * Remove a /proc entry and free it if it's not currently in use. | |
763 | */ | |
764 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
765 | { | |
766 | struct proc_dir_entry **p; | |
767 | struct proc_dir_entry *de = NULL; | |
768 | const char *fn = name; | |
769 | unsigned int len; | |
770 | ||
771 | spin_lock(&proc_subdir_lock); | |
772 | if (__xlate_proc_name(name, &parent, &fn) != 0) { | |
773 | spin_unlock(&proc_subdir_lock); | |
774 | return; | |
775 | } | |
776 | len = strlen(fn); | |
777 | ||
778 | for (p = &parent->subdir; *p; p=&(*p)->next ) { | |
779 | if (proc_match(len, fn, *p)) { | |
780 | de = *p; | |
781 | *p = de->next; | |
782 | de->next = NULL; | |
783 | break; | |
784 | } | |
785 | } | |
786 | spin_unlock(&proc_subdir_lock); | |
787 | if (!de) { | |
788 | WARN(1, "name '%s'\n", name); | |
789 | return; | |
790 | } | |
791 | ||
792 | entry_rundown(de); | |
881adb85 | 793 | |
f649d6d3 AD |
794 | if (S_ISDIR(de->mode)) |
795 | parent->nlink--; | |
796 | de->nlink = 0; | |
87ebdc00 AM |
797 | WARN(de->subdir, "%s: removing non-empty directory " |
798 | "'%s/%s', leaking at least '%s'\n", __func__, | |
799 | de->parent->name, de->name, de->subdir->name); | |
135d5655 | 800 | pde_put(de); |
1da177e4 | 801 | } |
587d4a17 | 802 | EXPORT_SYMBOL(remove_proc_entry); |
8ce584c7 AV |
803 | |
804 | int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) | |
805 | { | |
806 | struct proc_dir_entry **p; | |
807 | struct proc_dir_entry *root = NULL, *de, *next; | |
808 | const char *fn = name; | |
809 | unsigned int len; | |
810 | ||
811 | spin_lock(&proc_subdir_lock); | |
812 | if (__xlate_proc_name(name, &parent, &fn) != 0) { | |
813 | spin_unlock(&proc_subdir_lock); | |
814 | return -ENOENT; | |
815 | } | |
816 | len = strlen(fn); | |
817 | ||
818 | for (p = &parent->subdir; *p; p=&(*p)->next ) { | |
819 | if (proc_match(len, fn, *p)) { | |
820 | root = *p; | |
821 | *p = root->next; | |
822 | root->next = NULL; | |
823 | break; | |
824 | } | |
825 | } | |
826 | if (!root) { | |
827 | spin_unlock(&proc_subdir_lock); | |
828 | return -ENOENT; | |
829 | } | |
830 | de = root; | |
831 | while (1) { | |
832 | next = de->subdir; | |
833 | if (next) { | |
834 | de->subdir = next->next; | |
835 | next->next = NULL; | |
836 | de = next; | |
837 | continue; | |
838 | } | |
839 | spin_unlock(&proc_subdir_lock); | |
840 | ||
841 | entry_rundown(de); | |
842 | next = de->parent; | |
843 | if (S_ISDIR(de->mode)) | |
844 | next->nlink--; | |
845 | de->nlink = 0; | |
846 | if (de == root) | |
847 | break; | |
848 | pde_put(de); | |
849 | ||
850 | spin_lock(&proc_subdir_lock); | |
851 | de = next; | |
852 | } | |
853 | pde_put(root); | |
854 | return 0; | |
855 | } | |
856 | EXPORT_SYMBOL(remove_proc_subtree); |