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Commit | Line | Data |
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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> | |
15 | #include <linux/module.h> | |
5a0e3ad6 | 16 | #include <linux/slab.h> |
1da177e4 | 17 | #include <linux/mount.h> |
1da177e4 LT |
18 | #include <linux/init.h> |
19 | #include <linux/idr.h> | |
20 | #include <linux/namei.h> | |
21 | #include <linux/bitops.h> | |
64a07bd8 | 22 | #include <linux/spinlock.h> |
786d7e16 | 23 | #include <linux/completion.h> |
1da177e4 LT |
24 | #include <asm/uaccess.h> |
25 | ||
fee781e6 AB |
26 | #include "internal.h" |
27 | ||
64a07bd8 SR |
28 | DEFINE_SPINLOCK(proc_subdir_lock); |
29 | ||
77b14db5 | 30 | static int proc_match(int len, const char *name, struct proc_dir_entry *de) |
1da177e4 LT |
31 | { |
32 | if (de->namelen != len) | |
33 | return 0; | |
34 | return !memcmp(name, de->name, len); | |
35 | } | |
36 | ||
1da177e4 LT |
37 | /* buffer size is one page but our output routines use some slack for overruns */ |
38 | #define PROC_BLOCK_SIZE (PAGE_SIZE - 1024) | |
39 | ||
40 | static ssize_t | |
3dec7f59 | 41 | __proc_file_read(struct file *file, char __user *buf, size_t nbytes, |
1da177e4 LT |
42 | loff_t *ppos) |
43 | { | |
2fddfeef | 44 | struct inode * inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
45 | char *page; |
46 | ssize_t retval=0; | |
47 | int eof=0; | |
48 | ssize_t n, count; | |
49 | char *start; | |
50 | struct proc_dir_entry * dp; | |
8b90db0d LT |
51 | unsigned long long pos; |
52 | ||
53 | /* | |
54 | * Gaah, please just use "seq_file" instead. The legacy /proc | |
55 | * interfaces cut loff_t down to off_t for reads, and ignore | |
56 | * the offset entirely for writes.. | |
57 | */ | |
58 | pos = *ppos; | |
59 | if (pos > MAX_NON_LFS) | |
60 | return 0; | |
61 | if (nbytes > MAX_NON_LFS - pos) | |
62 | nbytes = MAX_NON_LFS - pos; | |
1da177e4 LT |
63 | |
64 | dp = PDE(inode); | |
e12ba74d | 65 | if (!(page = (char*) __get_free_page(GFP_TEMPORARY))) |
1da177e4 LT |
66 | return -ENOMEM; |
67 | ||
68 | while ((nbytes > 0) && !eof) { | |
69 | count = min_t(size_t, PROC_BLOCK_SIZE, nbytes); | |
70 | ||
71 | start = NULL; | |
8731f14d | 72 | if (dp->read_proc) { |
1da177e4 LT |
73 | /* |
74 | * How to be a proc read function | |
75 | * ------------------------------ | |
76 | * Prototype: | |
77 | * int f(char *buffer, char **start, off_t offset, | |
78 | * int count, int *peof, void *dat) | |
79 | * | |
80 | * Assume that the buffer is "count" bytes in size. | |
81 | * | |
82 | * If you know you have supplied all the data you | |
83 | * have, set *peof. | |
84 | * | |
85 | * You have three ways to return data: | |
86 | * 0) Leave *start = NULL. (This is the default.) | |
87 | * Put the data of the requested offset at that | |
88 | * offset within the buffer. Return the number (n) | |
89 | * of bytes there are from the beginning of the | |
90 | * buffer up to the last byte of data. If the | |
91 | * number of supplied bytes (= n - offset) is | |
92 | * greater than zero and you didn't signal eof | |
93 | * and the reader is prepared to take more data | |
94 | * you will be called again with the requested | |
95 | * offset advanced by the number of bytes | |
96 | * absorbed. This interface is useful for files | |
97 | * no larger than the buffer. | |
98 | * 1) Set *start = an unsigned long value less than | |
99 | * the buffer address but greater than zero. | |
100 | * Put the data of the requested offset at the | |
101 | * beginning of the buffer. Return the number of | |
102 | * bytes of data placed there. If this number is | |
103 | * greater than zero and you didn't signal eof | |
104 | * and the reader is prepared to take more data | |
105 | * you will be called again with the requested | |
106 | * offset advanced by *start. This interface is | |
107 | * useful when you have a large file consisting | |
108 | * of a series of blocks which you want to count | |
109 | * and return as wholes. | |
110 | * (Hack by Paul.Russell@rustcorp.com.au) | |
111 | * 2) Set *start = an address within the buffer. | |
112 | * Put the data of the requested offset at *start. | |
113 | * Return the number of bytes of data placed there. | |
114 | * If this number is greater than zero and you | |
115 | * didn't signal eof and the reader is prepared to | |
116 | * take more data you will be called again with the | |
117 | * requested offset advanced by the number of bytes | |
118 | * absorbed. | |
119 | */ | |
120 | n = dp->read_proc(page, &start, *ppos, | |
121 | count, &eof, dp->data); | |
122 | } else | |
123 | break; | |
124 | ||
125 | if (n == 0) /* end of file */ | |
126 | break; | |
127 | if (n < 0) { /* error */ | |
128 | if (retval == 0) | |
129 | retval = n; | |
130 | break; | |
131 | } | |
132 | ||
133 | if (start == NULL) { | |
134 | if (n > PAGE_SIZE) { | |
135 | printk(KERN_ERR | |
136 | "proc_file_read: Apparent buffer overflow!\n"); | |
137 | n = PAGE_SIZE; | |
138 | } | |
139 | n -= *ppos; | |
140 | if (n <= 0) | |
141 | break; | |
142 | if (n > count) | |
143 | n = count; | |
144 | start = page + *ppos; | |
145 | } else if (start < page) { | |
146 | if (n > PAGE_SIZE) { | |
147 | printk(KERN_ERR | |
148 | "proc_file_read: Apparent buffer overflow!\n"); | |
149 | n = PAGE_SIZE; | |
150 | } | |
151 | if (n > count) { | |
152 | /* | |
153 | * Don't reduce n because doing so might | |
154 | * cut off part of a data block. | |
155 | */ | |
156 | printk(KERN_WARNING | |
157 | "proc_file_read: Read count exceeded\n"); | |
158 | } | |
159 | } else /* start >= page */ { | |
160 | unsigned long startoff = (unsigned long)(start - page); | |
161 | if (n > (PAGE_SIZE - startoff)) { | |
162 | printk(KERN_ERR | |
163 | "proc_file_read: Apparent buffer overflow!\n"); | |
164 | n = PAGE_SIZE - startoff; | |
165 | } | |
166 | if (n > count) | |
167 | n = count; | |
168 | } | |
169 | ||
170 | n -= copy_to_user(buf, start < page ? page : start, n); | |
171 | if (n == 0) { | |
172 | if (retval == 0) | |
173 | retval = -EFAULT; | |
174 | break; | |
175 | } | |
176 | ||
177 | *ppos += start < page ? (unsigned long)start : n; | |
178 | nbytes -= n; | |
179 | buf += n; | |
180 | retval += n; | |
181 | } | |
182 | free_page((unsigned long) page); | |
183 | return retval; | |
184 | } | |
185 | ||
3dec7f59 AD |
186 | static ssize_t |
187 | proc_file_read(struct file *file, char __user *buf, size_t nbytes, | |
188 | loff_t *ppos) | |
189 | { | |
190 | struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); | |
191 | ssize_t rv = -EIO; | |
192 | ||
193 | spin_lock(&pde->pde_unload_lock); | |
194 | if (!pde->proc_fops) { | |
195 | spin_unlock(&pde->pde_unload_lock); | |
196 | return rv; | |
197 | } | |
198 | pde->pde_users++; | |
199 | spin_unlock(&pde->pde_unload_lock); | |
200 | ||
201 | rv = __proc_file_read(file, buf, nbytes, ppos); | |
202 | ||
203 | pde_users_dec(pde); | |
204 | return rv; | |
205 | } | |
206 | ||
1da177e4 LT |
207 | static ssize_t |
208 | proc_file_write(struct file *file, const char __user *buffer, | |
209 | size_t count, loff_t *ppos) | |
210 | { | |
3dec7f59 AD |
211 | struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); |
212 | ssize_t rv = -EIO; | |
213 | ||
214 | if (pde->write_proc) { | |
215 | spin_lock(&pde->pde_unload_lock); | |
216 | if (!pde->proc_fops) { | |
217 | spin_unlock(&pde->pde_unload_lock); | |
218 | return rv; | |
219 | } | |
220 | pde->pde_users++; | |
221 | spin_unlock(&pde->pde_unload_lock); | |
1da177e4 | 222 | |
3dec7f59 AD |
223 | /* FIXME: does this routine need ppos? probably... */ |
224 | rv = pde->write_proc(file, buffer, count, pde->data); | |
225 | pde_users_dec(pde); | |
226 | } | |
227 | return rv; | |
1da177e4 LT |
228 | } |
229 | ||
230 | ||
231 | static loff_t | |
232 | proc_file_lseek(struct file *file, loff_t offset, int orig) | |
233 | { | |
8b90db0d LT |
234 | loff_t retval = -EINVAL; |
235 | switch (orig) { | |
236 | case 1: | |
237 | offset += file->f_pos; | |
238 | /* fallthrough */ | |
239 | case 0: | |
240 | if (offset < 0 || offset > MAX_NON_LFS) | |
241 | break; | |
242 | file->f_pos = retval = offset; | |
243 | } | |
244 | return retval; | |
1da177e4 LT |
245 | } |
246 | ||
76df0c25 AD |
247 | static const struct file_operations proc_file_operations = { |
248 | .llseek = proc_file_lseek, | |
249 | .read = proc_file_read, | |
250 | .write = proc_file_write, | |
251 | }; | |
252 | ||
1da177e4 LT |
253 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) |
254 | { | |
255 | struct inode *inode = dentry->d_inode; | |
256 | struct proc_dir_entry *de = PDE(inode); | |
257 | int error; | |
258 | ||
259 | error = inode_change_ok(inode, iattr); | |
260 | if (error) | |
261 | goto out; | |
262 | ||
263 | error = inode_setattr(inode, iattr); | |
264 | if (error) | |
265 | goto out; | |
266 | ||
267 | de->uid = inode->i_uid; | |
268 | de->gid = inode->i_gid; | |
269 | de->mode = inode->i_mode; | |
270 | out: | |
271 | return error; | |
272 | } | |
273 | ||
2b579bee MS |
274 | static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry, |
275 | struct kstat *stat) | |
276 | { | |
277 | struct inode *inode = dentry->d_inode; | |
278 | struct proc_dir_entry *de = PROC_I(inode)->pde; | |
279 | if (de && de->nlink) | |
280 | inode->i_nlink = de->nlink; | |
281 | ||
282 | generic_fillattr(inode, stat); | |
283 | return 0; | |
284 | } | |
285 | ||
c5ef1c42 | 286 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
287 | .setattr = proc_notify_change, |
288 | }; | |
289 | ||
290 | /* | |
291 | * This function parses a name such as "tty/driver/serial", and | |
292 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
293 | * returns "serial" in residual. | |
294 | */ | |
e17a5765 AD |
295 | static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret, |
296 | const char **residual) | |
1da177e4 LT |
297 | { |
298 | const char *cp = name, *next; | |
299 | struct proc_dir_entry *de; | |
300 | int len; | |
301 | ||
7cee4e00 AD |
302 | de = *ret; |
303 | if (!de) | |
304 | de = &proc_root; | |
305 | ||
1da177e4 LT |
306 | while (1) { |
307 | next = strchr(cp, '/'); | |
308 | if (!next) | |
309 | break; | |
310 | ||
311 | len = next - cp; | |
312 | for (de = de->subdir; de ; de = de->next) { | |
313 | if (proc_match(len, cp, de)) | |
314 | break; | |
315 | } | |
12bac0d9 AD |
316 | if (!de) { |
317 | WARN(1, "name '%s'\n", name); | |
e17a5765 | 318 | return -ENOENT; |
12bac0d9 | 319 | } |
1da177e4 LT |
320 | cp += len + 1; |
321 | } | |
322 | *residual = cp; | |
323 | *ret = de; | |
e17a5765 AD |
324 | return 0; |
325 | } | |
326 | ||
327 | static int xlate_proc_name(const char *name, struct proc_dir_entry **ret, | |
328 | const char **residual) | |
329 | { | |
330 | int rv; | |
331 | ||
332 | spin_lock(&proc_subdir_lock); | |
333 | rv = __xlate_proc_name(name, ret, residual); | |
64a07bd8 | 334 | spin_unlock(&proc_subdir_lock); |
e17a5765 | 335 | return rv; |
1da177e4 LT |
336 | } |
337 | ||
9a185409 | 338 | static DEFINE_IDA(proc_inum_ida); |
1da177e4 LT |
339 | static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ |
340 | ||
67935df4 | 341 | #define PROC_DYNAMIC_FIRST 0xF0000000U |
1da177e4 LT |
342 | |
343 | /* | |
344 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
345 | * 0xffffffff, or zero on failure. | |
1681bc30 RD |
346 | * |
347 | * Current inode allocations in the proc-fs (hex-numbers): | |
348 | * | |
349 | * 00000000 reserved | |
350 | * 00000001-00000fff static entries (goners) | |
351 | * 001 root-ino | |
352 | * | |
353 | * 00001000-00001fff unused | |
354 | * 0001xxxx-7fffxxxx pid-dir entries for pid 1-7fff | |
355 | * 80000000-efffffff unused | |
356 | * f0000000-ffffffff dynamic entries | |
357 | * | |
358 | * Goal: | |
359 | * Once we split the thing into several virtual filesystems, | |
360 | * we will get rid of magical ranges (and this comment, BTW). | |
1da177e4 LT |
361 | */ |
362 | static unsigned int get_inode_number(void) | |
363 | { | |
67935df4 | 364 | unsigned int i; |
1da177e4 LT |
365 | int error; |
366 | ||
367 | retry: | |
9a185409 | 368 | if (ida_pre_get(&proc_inum_ida, GFP_KERNEL) == 0) |
1da177e4 LT |
369 | return 0; |
370 | ||
371 | spin_lock(&proc_inum_lock); | |
9a185409 | 372 | error = ida_get_new(&proc_inum_ida, &i); |
1da177e4 LT |
373 | spin_unlock(&proc_inum_lock); |
374 | if (error == -EAGAIN) | |
375 | goto retry; | |
376 | else if (error) | |
377 | return 0; | |
378 | ||
67935df4 AD |
379 | if (i > UINT_MAX - PROC_DYNAMIC_FIRST) { |
380 | spin_lock(&proc_inum_lock); | |
9a185409 | 381 | ida_remove(&proc_inum_ida, i); |
67935df4 | 382 | spin_unlock(&proc_inum_lock); |
cc996099 | 383 | return 0; |
67935df4 AD |
384 | } |
385 | return PROC_DYNAMIC_FIRST + i; | |
1da177e4 LT |
386 | } |
387 | ||
388 | static void release_inode_number(unsigned int inum) | |
389 | { | |
1da177e4 | 390 | spin_lock(&proc_inum_lock); |
9a185409 | 391 | ida_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); |
1da177e4 LT |
392 | spin_unlock(&proc_inum_lock); |
393 | } | |
394 | ||
008b150a | 395 | static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
396 | { |
397 | nd_set_link(nd, PDE(dentry->d_inode)->data); | |
008b150a | 398 | return NULL; |
1da177e4 LT |
399 | } |
400 | ||
c5ef1c42 | 401 | static const struct inode_operations proc_link_inode_operations = { |
1da177e4 LT |
402 | .readlink = generic_readlink, |
403 | .follow_link = proc_follow_link, | |
404 | }; | |
405 | ||
406 | /* | |
407 | * As some entries in /proc are volatile, we want to | |
408 | * get rid of unused dentries. This could be made | |
409 | * smarter: we could keep a "volatile" flag in the | |
410 | * inode to indicate which ones to keep. | |
411 | */ | |
412 | static int proc_delete_dentry(struct dentry * dentry) | |
413 | { | |
414 | return 1; | |
415 | } | |
416 | ||
d72f71eb | 417 | static const struct dentry_operations proc_dentry_operations = |
1da177e4 LT |
418 | { |
419 | .d_delete = proc_delete_dentry, | |
420 | }; | |
421 | ||
422 | /* | |
423 | * Don't create negative dentries here, return -ENOENT by hand | |
424 | * instead. | |
425 | */ | |
e9720acd PE |
426 | struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir, |
427 | struct dentry *dentry) | |
1da177e4 LT |
428 | { |
429 | struct inode *inode = NULL; | |
1da177e4 LT |
430 | int error = -ENOENT; |
431 | ||
64a07bd8 | 432 | spin_lock(&proc_subdir_lock); |
5e971dce AD |
433 | for (de = de->subdir; de ; de = de->next) { |
434 | if (de->namelen != dentry->d_name.len) | |
435 | continue; | |
436 | if (!memcmp(dentry->d_name.name, de->name, de->namelen)) { | |
437 | unsigned int ino; | |
438 | ||
439 | ino = de->low_ino; | |
135d5655 | 440 | pde_get(de); |
5e971dce AD |
441 | spin_unlock(&proc_subdir_lock); |
442 | error = -EINVAL; | |
443 | inode = proc_get_inode(dir->i_sb, ino, de); | |
444 | goto out_unlock; | |
1da177e4 LT |
445 | } |
446 | } | |
64a07bd8 | 447 | spin_unlock(&proc_subdir_lock); |
4237e0d3 | 448 | out_unlock: |
1da177e4 LT |
449 | |
450 | if (inode) { | |
451 | dentry->d_op = &proc_dentry_operations; | |
452 | d_add(dentry, inode); | |
453 | return NULL; | |
454 | } | |
5e971dce | 455 | if (de) |
135d5655 | 456 | pde_put(de); |
1da177e4 LT |
457 | return ERR_PTR(error); |
458 | } | |
459 | ||
e9720acd PE |
460 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
461 | struct nameidata *nd) | |
462 | { | |
463 | return proc_lookup_de(PDE(dir), dir, dentry); | |
464 | } | |
465 | ||
1da177e4 LT |
466 | /* |
467 | * This returns non-zero if at EOF, so that the /proc | |
468 | * root directory can use this and check if it should | |
469 | * continue with the <pid> entries.. | |
470 | * | |
471 | * Note that the VFS-layer doesn't care about the return | |
472 | * value of the readdir() call, as long as it's non-negative | |
473 | * for success.. | |
474 | */ | |
e9720acd PE |
475 | int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent, |
476 | filldir_t filldir) | |
1da177e4 | 477 | { |
1da177e4 LT |
478 | unsigned int ino; |
479 | int i; | |
2fddfeef | 480 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
481 | int ret = 0; |
482 | ||
1da177e4 | 483 | ino = inode->i_ino; |
1da177e4 LT |
484 | i = filp->f_pos; |
485 | switch (i) { | |
486 | case 0: | |
487 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
488 | goto out; | |
489 | i++; | |
490 | filp->f_pos++; | |
491 | /* fall through */ | |
492 | case 1: | |
493 | if (filldir(dirent, "..", 2, i, | |
2fddfeef | 494 | parent_ino(filp->f_path.dentry), |
1da177e4 LT |
495 | DT_DIR) < 0) |
496 | goto out; | |
497 | i++; | |
498 | filp->f_pos++; | |
499 | /* fall through */ | |
500 | default: | |
64a07bd8 | 501 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
502 | de = de->subdir; |
503 | i -= 2; | |
504 | for (;;) { | |
505 | if (!de) { | |
506 | ret = 1; | |
64a07bd8 | 507 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
508 | goto out; |
509 | } | |
510 | if (!i) | |
511 | break; | |
512 | de = de->next; | |
513 | i--; | |
514 | } | |
515 | ||
516 | do { | |
59cd0cbc DW |
517 | struct proc_dir_entry *next; |
518 | ||
64a07bd8 | 519 | /* filldir passes info to user space */ |
135d5655 | 520 | pde_get(de); |
64a07bd8 | 521 | spin_unlock(&proc_subdir_lock); |
1da177e4 | 522 | if (filldir(dirent, de->name, de->namelen, filp->f_pos, |
59cd0cbc | 523 | de->low_ino, de->mode >> 12) < 0) { |
135d5655 | 524 | pde_put(de); |
1da177e4 | 525 | goto out; |
59cd0cbc | 526 | } |
64a07bd8 | 527 | spin_lock(&proc_subdir_lock); |
1da177e4 | 528 | filp->f_pos++; |
59cd0cbc | 529 | next = de->next; |
135d5655 | 530 | pde_put(de); |
59cd0cbc | 531 | de = next; |
1da177e4 | 532 | } while (de); |
64a07bd8 | 533 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
534 | } |
535 | ret = 1; | |
b4df2b92 | 536 | out: |
1da177e4 LT |
537 | return ret; |
538 | } | |
539 | ||
e9720acd PE |
540 | int proc_readdir(struct file *filp, void *dirent, filldir_t filldir) |
541 | { | |
542 | struct inode *inode = filp->f_path.dentry->d_inode; | |
543 | ||
544 | return proc_readdir_de(PDE(inode), filp, dirent, filldir); | |
545 | } | |
546 | ||
1da177e4 LT |
547 | /* |
548 | * These are the generic /proc directory operations. They | |
549 | * use the in-memory "struct proc_dir_entry" tree to parse | |
550 | * the /proc directory. | |
551 | */ | |
00977a59 | 552 | static const struct file_operations proc_dir_operations = { |
b4df2b92 | 553 | .llseek = generic_file_llseek, |
1da177e4 LT |
554 | .read = generic_read_dir, |
555 | .readdir = proc_readdir, | |
556 | }; | |
557 | ||
558 | /* | |
559 | * proc directories can do almost nothing.. | |
560 | */ | |
c5ef1c42 | 561 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 562 | .lookup = proc_lookup, |
2b579bee | 563 | .getattr = proc_getattr, |
1da177e4 LT |
564 | .setattr = proc_notify_change, |
565 | }; | |
566 | ||
567 | static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) | |
568 | { | |
569 | unsigned int i; | |
94413d88 | 570 | struct proc_dir_entry *tmp; |
1da177e4 LT |
571 | |
572 | i = get_inode_number(); | |
573 | if (i == 0) | |
574 | return -EAGAIN; | |
575 | dp->low_ino = i; | |
64a07bd8 | 576 | |
1da177e4 LT |
577 | if (S_ISDIR(dp->mode)) { |
578 | if (dp->proc_iops == NULL) { | |
579 | dp->proc_fops = &proc_dir_operations; | |
580 | dp->proc_iops = &proc_dir_inode_operations; | |
581 | } | |
582 | dir->nlink++; | |
583 | } else if (S_ISLNK(dp->mode)) { | |
584 | if (dp->proc_iops == NULL) | |
585 | dp->proc_iops = &proc_link_inode_operations; | |
586 | } else if (S_ISREG(dp->mode)) { | |
587 | if (dp->proc_fops == NULL) | |
588 | dp->proc_fops = &proc_file_operations; | |
589 | if (dp->proc_iops == NULL) | |
590 | dp->proc_iops = &proc_file_inode_operations; | |
591 | } | |
99fc06df CG |
592 | |
593 | spin_lock(&proc_subdir_lock); | |
94413d88 ZR |
594 | |
595 | for (tmp = dir->subdir; tmp; tmp = tmp->next) | |
596 | if (strcmp(tmp->name, dp->name) == 0) { | |
6c2f91e0 | 597 | WARN(1, KERN_WARNING "proc_dir_entry '%s/%s' already registered\n", |
665020c3 | 598 | dir->name, dp->name); |
94413d88 ZR |
599 | break; |
600 | } | |
601 | ||
99fc06df CG |
602 | dp->next = dir->subdir; |
603 | dp->parent = dir; | |
604 | dir->subdir = dp; | |
605 | spin_unlock(&proc_subdir_lock); | |
606 | ||
1da177e4 LT |
607 | return 0; |
608 | } | |
609 | ||
2d3a4e36 | 610 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 LT |
611 | const char *name, |
612 | mode_t mode, | |
613 | nlink_t nlink) | |
614 | { | |
615 | struct proc_dir_entry *ent = NULL; | |
616 | const char *fn = name; | |
617 | int len; | |
618 | ||
619 | /* make sure name is valid */ | |
620 | if (!name || !strlen(name)) goto out; | |
621 | ||
7cee4e00 | 622 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 LT |
623 | goto out; |
624 | ||
625 | /* At this point there must not be any '/' characters beyond *fn */ | |
626 | if (strchr(fn, '/')) | |
627 | goto out; | |
628 | ||
629 | len = strlen(fn); | |
630 | ||
631 | ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL); | |
632 | if (!ent) goto out; | |
633 | ||
634 | memset(ent, 0, sizeof(struct proc_dir_entry)); | |
635 | memcpy(((char *) ent) + sizeof(struct proc_dir_entry), fn, len + 1); | |
636 | ent->name = ((char *) ent) + sizeof(*ent); | |
637 | ent->namelen = len; | |
638 | ent->mode = mode; | |
639 | ent->nlink = nlink; | |
5a622f2d | 640 | atomic_set(&ent->count, 1); |
786d7e16 AD |
641 | ent->pde_users = 0; |
642 | spin_lock_init(&ent->pde_unload_lock); | |
643 | ent->pde_unload_completion = NULL; | |
881adb85 | 644 | INIT_LIST_HEAD(&ent->pde_openers); |
1da177e4 LT |
645 | out: |
646 | return ent; | |
647 | } | |
648 | ||
649 | struct proc_dir_entry *proc_symlink(const char *name, | |
650 | struct proc_dir_entry *parent, const char *dest) | |
651 | { | |
652 | struct proc_dir_entry *ent; | |
653 | ||
2d3a4e36 | 654 | ent = __proc_create(&parent, name, |
1da177e4 LT |
655 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
656 | ||
657 | if (ent) { | |
658 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
659 | if (ent->data) { | |
660 | strcpy((char*)ent->data,dest); | |
661 | if (proc_register(parent, ent) < 0) { | |
662 | kfree(ent->data); | |
663 | kfree(ent); | |
664 | ent = NULL; | |
665 | } | |
666 | } else { | |
667 | kfree(ent); | |
668 | ent = NULL; | |
669 | } | |
670 | } | |
671 | return ent; | |
672 | } | |
587d4a17 | 673 | EXPORT_SYMBOL(proc_symlink); |
1da177e4 LT |
674 | |
675 | struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode, | |
676 | struct proc_dir_entry *parent) | |
677 | { | |
678 | struct proc_dir_entry *ent; | |
679 | ||
2d3a4e36 | 680 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 681 | if (ent) { |
1da177e4 LT |
682 | if (proc_register(parent, ent) < 0) { |
683 | kfree(ent); | |
684 | ent = NULL; | |
685 | } | |
686 | } | |
687 | return ent; | |
688 | } | |
689 | ||
78e92b99 DL |
690 | struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name, |
691 | struct proc_dir_entry *parent) | |
692 | { | |
693 | struct proc_dir_entry *ent; | |
694 | ||
695 | ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2); | |
696 | if (ent) { | |
697 | ent->data = net; | |
698 | if (proc_register(parent, ent) < 0) { | |
699 | kfree(ent); | |
700 | ent = NULL; | |
701 | } | |
702 | } | |
703 | return ent; | |
704 | } | |
705 | EXPORT_SYMBOL_GPL(proc_net_mkdir); | |
706 | ||
1da177e4 LT |
707 | struct proc_dir_entry *proc_mkdir(const char *name, |
708 | struct proc_dir_entry *parent) | |
709 | { | |
710 | return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); | |
711 | } | |
587d4a17 | 712 | EXPORT_SYMBOL(proc_mkdir); |
1da177e4 LT |
713 | |
714 | struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode, | |
715 | struct proc_dir_entry *parent) | |
716 | { | |
717 | struct proc_dir_entry *ent; | |
718 | nlink_t nlink; | |
719 | ||
720 | if (S_ISDIR(mode)) { | |
721 | if ((mode & S_IALLUGO) == 0) | |
722 | mode |= S_IRUGO | S_IXUGO; | |
723 | nlink = 2; | |
724 | } else { | |
725 | if ((mode & S_IFMT) == 0) | |
726 | mode |= S_IFREG; | |
727 | if ((mode & S_IALLUGO) == 0) | |
728 | mode |= S_IRUGO; | |
729 | nlink = 1; | |
730 | } | |
731 | ||
2d3a4e36 | 732 | ent = __proc_create(&parent, name, mode, nlink); |
1da177e4 | 733 | if (ent) { |
1da177e4 LT |
734 | if (proc_register(parent, ent) < 0) { |
735 | kfree(ent); | |
736 | ent = NULL; | |
737 | } | |
738 | } | |
739 | return ent; | |
740 | } | |
587d4a17 | 741 | EXPORT_SYMBOL(create_proc_entry); |
1da177e4 | 742 | |
59b74351 DL |
743 | struct proc_dir_entry *proc_create_data(const char *name, mode_t mode, |
744 | struct proc_dir_entry *parent, | |
745 | const struct file_operations *proc_fops, | |
746 | void *data) | |
2d3a4e36 AD |
747 | { |
748 | struct proc_dir_entry *pde; | |
749 | nlink_t nlink; | |
750 | ||
751 | if (S_ISDIR(mode)) { | |
752 | if ((mode & S_IALLUGO) == 0) | |
753 | mode |= S_IRUGO | S_IXUGO; | |
754 | nlink = 2; | |
755 | } else { | |
756 | if ((mode & S_IFMT) == 0) | |
757 | mode |= S_IFREG; | |
758 | if ((mode & S_IALLUGO) == 0) | |
759 | mode |= S_IRUGO; | |
760 | nlink = 1; | |
761 | } | |
762 | ||
763 | pde = __proc_create(&parent, name, mode, nlink); | |
764 | if (!pde) | |
765 | goto out; | |
766 | pde->proc_fops = proc_fops; | |
59b74351 | 767 | pde->data = data; |
2d3a4e36 AD |
768 | if (proc_register(parent, pde) < 0) |
769 | goto out_free; | |
770 | return pde; | |
771 | out_free: | |
772 | kfree(pde); | |
773 | out: | |
774 | return NULL; | |
775 | } | |
587d4a17 | 776 | EXPORT_SYMBOL(proc_create_data); |
2d3a4e36 | 777 | |
135d5655 | 778 | static void free_proc_entry(struct proc_dir_entry *de) |
1da177e4 LT |
779 | { |
780 | unsigned int ino = de->low_ino; | |
781 | ||
782 | if (ino < PROC_DYNAMIC_FIRST) | |
783 | return; | |
784 | ||
785 | release_inode_number(ino); | |
786 | ||
fd2cbe48 | 787 | if (S_ISLNK(de->mode)) |
1da177e4 LT |
788 | kfree(de->data); |
789 | kfree(de); | |
790 | } | |
791 | ||
135d5655 AD |
792 | void pde_put(struct proc_dir_entry *pde) |
793 | { | |
794 | if (atomic_dec_and_test(&pde->count)) | |
795 | free_proc_entry(pde); | |
796 | } | |
797 | ||
1da177e4 LT |
798 | /* |
799 | * Remove a /proc entry and free it if it's not currently in use. | |
1da177e4 LT |
800 | */ |
801 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
802 | { | |
803 | struct proc_dir_entry **p; | |
f649d6d3 | 804 | struct proc_dir_entry *de = NULL; |
1da177e4 LT |
805 | const char *fn = name; |
806 | int len; | |
807 | ||
e17a5765 AD |
808 | spin_lock(&proc_subdir_lock); |
809 | if (__xlate_proc_name(name, &parent, &fn) != 0) { | |
810 | spin_unlock(&proc_subdir_lock); | |
f649d6d3 | 811 | return; |
e17a5765 | 812 | } |
1da177e4 | 813 | len = strlen(fn); |
64a07bd8 | 814 | |
1da177e4 | 815 | for (p = &parent->subdir; *p; p=&(*p)->next ) { |
f649d6d3 AD |
816 | if (proc_match(len, fn, *p)) { |
817 | de = *p; | |
818 | *p = de->next; | |
819 | de->next = NULL; | |
820 | break; | |
821 | } | |
822 | } | |
823 | spin_unlock(&proc_subdir_lock); | |
12bac0d9 AD |
824 | if (!de) { |
825 | WARN(1, "name '%s'\n", name); | |
f649d6d3 | 826 | return; |
12bac0d9 | 827 | } |
786d7e16 | 828 | |
f649d6d3 AD |
829 | spin_lock(&de->pde_unload_lock); |
830 | /* | |
831 | * Stop accepting new callers into module. If you're | |
832 | * dynamically allocating ->proc_fops, save a pointer somewhere. | |
833 | */ | |
834 | de->proc_fops = NULL; | |
835 | /* Wait until all existing callers into module are done. */ | |
836 | if (de->pde_users > 0) { | |
837 | DECLARE_COMPLETION_ONSTACK(c); | |
838 | ||
839 | if (!de->pde_unload_completion) | |
840 | de->pde_unload_completion = &c; | |
786d7e16 | 841 | |
786d7e16 AD |
842 | spin_unlock(&de->pde_unload_lock); |
843 | ||
f649d6d3 AD |
844 | wait_for_completion(de->pde_unload_completion); |
845 | ||
846 | goto continue_removing; | |
847 | } | |
848 | spin_unlock(&de->pde_unload_lock); | |
849 | ||
786d7e16 | 850 | continue_removing: |
881adb85 AD |
851 | spin_lock(&de->pde_unload_lock); |
852 | while (!list_empty(&de->pde_openers)) { | |
853 | struct pde_opener *pdeo; | |
854 | ||
855 | pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh); | |
856 | list_del(&pdeo->lh); | |
857 | spin_unlock(&de->pde_unload_lock); | |
858 | pdeo->release(pdeo->inode, pdeo->file); | |
859 | kfree(pdeo); | |
860 | spin_lock(&de->pde_unload_lock); | |
861 | } | |
862 | spin_unlock(&de->pde_unload_lock); | |
863 | ||
f649d6d3 AD |
864 | if (S_ISDIR(de->mode)) |
865 | parent->nlink--; | |
866 | de->nlink = 0; | |
267e2a9c | 867 | WARN(de->subdir, KERN_WARNING "%s: removing non-empty directory " |
f649d6d3 AD |
868 | "'%s/%s', leaking at least '%s'\n", __func__, |
869 | de->parent->name, de->name, de->subdir->name); | |
135d5655 | 870 | pde_put(de); |
1da177e4 | 871 | } |
587d4a17 | 872 | EXPORT_SYMBOL(remove_proc_entry); |