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> | |
15 | #include <linux/module.h> | |
16 | #include <linux/mount.h> | |
17 | #include <linux/smp_lock.h> | |
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 | |
41 | proc_file_read(struct file *file, char __user *buf, size_t nbytes, | |
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 | ||
186 | static ssize_t | |
187 | proc_file_write(struct file *file, const char __user *buffer, | |
188 | size_t count, loff_t *ppos) | |
189 | { | |
2fddfeef | 190 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
191 | struct proc_dir_entry * dp; |
192 | ||
193 | dp = PDE(inode); | |
194 | ||
195 | if (!dp->write_proc) | |
196 | return -EIO; | |
197 | ||
198 | /* FIXME: does this routine need ppos? probably... */ | |
199 | return dp->write_proc(file, buffer, count, dp->data); | |
200 | } | |
201 | ||
202 | ||
203 | static loff_t | |
204 | proc_file_lseek(struct file *file, loff_t offset, int orig) | |
205 | { | |
8b90db0d LT |
206 | loff_t retval = -EINVAL; |
207 | switch (orig) { | |
208 | case 1: | |
209 | offset += file->f_pos; | |
210 | /* fallthrough */ | |
211 | case 0: | |
212 | if (offset < 0 || offset > MAX_NON_LFS) | |
213 | break; | |
214 | file->f_pos = retval = offset; | |
215 | } | |
216 | return retval; | |
1da177e4 LT |
217 | } |
218 | ||
76df0c25 AD |
219 | static const struct file_operations proc_file_operations = { |
220 | .llseek = proc_file_lseek, | |
221 | .read = proc_file_read, | |
222 | .write = proc_file_write, | |
223 | }; | |
224 | ||
1da177e4 LT |
225 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) |
226 | { | |
227 | struct inode *inode = dentry->d_inode; | |
228 | struct proc_dir_entry *de = PDE(inode); | |
229 | int error; | |
230 | ||
231 | error = inode_change_ok(inode, iattr); | |
232 | if (error) | |
233 | goto out; | |
234 | ||
235 | error = inode_setattr(inode, iattr); | |
236 | if (error) | |
237 | goto out; | |
238 | ||
239 | de->uid = inode->i_uid; | |
240 | de->gid = inode->i_gid; | |
241 | de->mode = inode->i_mode; | |
242 | out: | |
243 | return error; | |
244 | } | |
245 | ||
2b579bee MS |
246 | static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry, |
247 | struct kstat *stat) | |
248 | { | |
249 | struct inode *inode = dentry->d_inode; | |
250 | struct proc_dir_entry *de = PROC_I(inode)->pde; | |
251 | if (de && de->nlink) | |
252 | inode->i_nlink = de->nlink; | |
253 | ||
254 | generic_fillattr(inode, stat); | |
255 | return 0; | |
256 | } | |
257 | ||
c5ef1c42 | 258 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
259 | .setattr = proc_notify_change, |
260 | }; | |
261 | ||
262 | /* | |
263 | * This function parses a name such as "tty/driver/serial", and | |
264 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
265 | * returns "serial" in residual. | |
266 | */ | |
267 | static int xlate_proc_name(const char *name, | |
268 | struct proc_dir_entry **ret, const char **residual) | |
269 | { | |
270 | const char *cp = name, *next; | |
271 | struct proc_dir_entry *de; | |
272 | int len; | |
64a07bd8 | 273 | int rtn = 0; |
1da177e4 | 274 | |
7cee4e00 AD |
275 | de = *ret; |
276 | if (!de) | |
277 | de = &proc_root; | |
278 | ||
64a07bd8 | 279 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
280 | while (1) { |
281 | next = strchr(cp, '/'); | |
282 | if (!next) | |
283 | break; | |
284 | ||
285 | len = next - cp; | |
286 | for (de = de->subdir; de ; de = de->next) { | |
287 | if (proc_match(len, cp, de)) | |
288 | break; | |
289 | } | |
64a07bd8 SR |
290 | if (!de) { |
291 | rtn = -ENOENT; | |
292 | goto out; | |
293 | } | |
1da177e4 LT |
294 | cp += len + 1; |
295 | } | |
296 | *residual = cp; | |
297 | *ret = de; | |
64a07bd8 SR |
298 | out: |
299 | spin_unlock(&proc_subdir_lock); | |
300 | return rtn; | |
1da177e4 LT |
301 | } |
302 | ||
303 | static DEFINE_IDR(proc_inum_idr); | |
304 | static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ | |
305 | ||
306 | #define PROC_DYNAMIC_FIRST 0xF0000000UL | |
307 | ||
308 | /* | |
309 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
310 | * 0xffffffff, or zero on failure. | |
311 | */ | |
312 | static unsigned int get_inode_number(void) | |
313 | { | |
314 | int i, inum = 0; | |
315 | int error; | |
316 | ||
317 | retry: | |
318 | if (idr_pre_get(&proc_inum_idr, GFP_KERNEL) == 0) | |
319 | return 0; | |
320 | ||
321 | spin_lock(&proc_inum_lock); | |
322 | error = idr_get_new(&proc_inum_idr, NULL, &i); | |
323 | spin_unlock(&proc_inum_lock); | |
324 | if (error == -EAGAIN) | |
325 | goto retry; | |
326 | else if (error) | |
327 | return 0; | |
328 | ||
329 | inum = (i & MAX_ID_MASK) + PROC_DYNAMIC_FIRST; | |
330 | ||
331 | /* inum will never be more than 0xf0ffffff, so no check | |
332 | * for overflow. | |
333 | */ | |
334 | ||
335 | return inum; | |
336 | } | |
337 | ||
338 | static void release_inode_number(unsigned int inum) | |
339 | { | |
340 | int id = (inum - PROC_DYNAMIC_FIRST) | ~MAX_ID_MASK; | |
341 | ||
342 | spin_lock(&proc_inum_lock); | |
343 | idr_remove(&proc_inum_idr, id); | |
344 | spin_unlock(&proc_inum_lock); | |
345 | } | |
346 | ||
008b150a | 347 | static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
348 | { |
349 | nd_set_link(nd, PDE(dentry->d_inode)->data); | |
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 | */ | |
364 | static int proc_delete_dentry(struct dentry * dentry) | |
365 | { | |
366 | return 1; | |
367 | } | |
368 | ||
369 | static struct dentry_operations proc_dentry_operations = | |
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 LT |
380 | { |
381 | struct inode *inode = NULL; | |
1da177e4 LT |
382 | int error = -ENOENT; |
383 | ||
384 | lock_kernel(); | |
64a07bd8 | 385 | spin_lock(&proc_subdir_lock); |
5e971dce AD |
386 | for (de = de->subdir; de ; de = de->next) { |
387 | if (de->namelen != dentry->d_name.len) | |
388 | continue; | |
389 | if (!memcmp(dentry->d_name.name, de->name, de->namelen)) { | |
390 | unsigned int ino; | |
391 | ||
392 | ino = de->low_ino; | |
393 | de_get(de); | |
394 | spin_unlock(&proc_subdir_lock); | |
395 | error = -EINVAL; | |
396 | inode = proc_get_inode(dir->i_sb, ino, de); | |
397 | goto out_unlock; | |
1da177e4 LT |
398 | } |
399 | } | |
64a07bd8 | 400 | spin_unlock(&proc_subdir_lock); |
4237e0d3 | 401 | out_unlock: |
1da177e4 LT |
402 | unlock_kernel(); |
403 | ||
404 | if (inode) { | |
405 | dentry->d_op = &proc_dentry_operations; | |
406 | d_add(dentry, inode); | |
407 | return NULL; | |
408 | } | |
5e971dce AD |
409 | if (de) |
410 | de_put(de); | |
1da177e4 LT |
411 | return ERR_PTR(error); |
412 | } | |
413 | ||
e9720acd PE |
414 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
415 | struct nameidata *nd) | |
416 | { | |
417 | return proc_lookup_de(PDE(dir), dir, dentry); | |
418 | } | |
419 | ||
1da177e4 LT |
420 | /* |
421 | * This returns non-zero if at EOF, so that the /proc | |
422 | * root directory can use this and check if it should | |
423 | * continue with the <pid> entries.. | |
424 | * | |
425 | * Note that the VFS-layer doesn't care about the return | |
426 | * value of the readdir() call, as long as it's non-negative | |
427 | * for success.. | |
428 | */ | |
e9720acd PE |
429 | int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent, |
430 | filldir_t filldir) | |
1da177e4 | 431 | { |
1da177e4 LT |
432 | unsigned int ino; |
433 | int i; | |
2fddfeef | 434 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
435 | int ret = 0; |
436 | ||
437 | lock_kernel(); | |
438 | ||
439 | ino = inode->i_ino; | |
1da177e4 LT |
440 | i = filp->f_pos; |
441 | switch (i) { | |
442 | case 0: | |
443 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
444 | goto out; | |
445 | i++; | |
446 | filp->f_pos++; | |
447 | /* fall through */ | |
448 | case 1: | |
449 | if (filldir(dirent, "..", 2, i, | |
2fddfeef | 450 | parent_ino(filp->f_path.dentry), |
1da177e4 LT |
451 | DT_DIR) < 0) |
452 | goto out; | |
453 | i++; | |
454 | filp->f_pos++; | |
455 | /* fall through */ | |
456 | default: | |
64a07bd8 | 457 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
458 | de = de->subdir; |
459 | i -= 2; | |
460 | for (;;) { | |
461 | if (!de) { | |
462 | ret = 1; | |
64a07bd8 | 463 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
464 | goto out; |
465 | } | |
466 | if (!i) | |
467 | break; | |
468 | de = de->next; | |
469 | i--; | |
470 | } | |
471 | ||
472 | do { | |
59cd0cbc DW |
473 | struct proc_dir_entry *next; |
474 | ||
64a07bd8 | 475 | /* filldir passes info to user space */ |
59cd0cbc | 476 | de_get(de); |
64a07bd8 | 477 | spin_unlock(&proc_subdir_lock); |
1da177e4 | 478 | if (filldir(dirent, de->name, de->namelen, filp->f_pos, |
59cd0cbc DW |
479 | de->low_ino, de->mode >> 12) < 0) { |
480 | de_put(de); | |
1da177e4 | 481 | goto out; |
59cd0cbc | 482 | } |
64a07bd8 | 483 | spin_lock(&proc_subdir_lock); |
1da177e4 | 484 | filp->f_pos++; |
59cd0cbc DW |
485 | next = de->next; |
486 | de_put(de); | |
487 | de = next; | |
1da177e4 | 488 | } while (de); |
64a07bd8 | 489 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
490 | } |
491 | ret = 1; | |
492 | out: unlock_kernel(); | |
493 | return ret; | |
494 | } | |
495 | ||
e9720acd PE |
496 | int proc_readdir(struct file *filp, void *dirent, filldir_t filldir) |
497 | { | |
498 | struct inode *inode = filp->f_path.dentry->d_inode; | |
499 | ||
500 | return proc_readdir_de(PDE(inode), filp, dirent, filldir); | |
501 | } | |
502 | ||
1da177e4 LT |
503 | /* |
504 | * These are the generic /proc directory operations. They | |
505 | * use the in-memory "struct proc_dir_entry" tree to parse | |
506 | * the /proc directory. | |
507 | */ | |
00977a59 | 508 | static const struct file_operations proc_dir_operations = { |
1da177e4 LT |
509 | .read = generic_read_dir, |
510 | .readdir = proc_readdir, | |
511 | }; | |
512 | ||
513 | /* | |
514 | * proc directories can do almost nothing.. | |
515 | */ | |
c5ef1c42 | 516 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 517 | .lookup = proc_lookup, |
2b579bee | 518 | .getattr = proc_getattr, |
1da177e4 LT |
519 | .setattr = proc_notify_change, |
520 | }; | |
521 | ||
522 | static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) | |
523 | { | |
524 | unsigned int i; | |
94413d88 | 525 | struct proc_dir_entry *tmp; |
1da177e4 LT |
526 | |
527 | i = get_inode_number(); | |
528 | if (i == 0) | |
529 | return -EAGAIN; | |
530 | dp->low_ino = i; | |
64a07bd8 | 531 | |
1da177e4 LT |
532 | if (S_ISDIR(dp->mode)) { |
533 | if (dp->proc_iops == NULL) { | |
534 | dp->proc_fops = &proc_dir_operations; | |
535 | dp->proc_iops = &proc_dir_inode_operations; | |
536 | } | |
537 | dir->nlink++; | |
538 | } else if (S_ISLNK(dp->mode)) { | |
539 | if (dp->proc_iops == NULL) | |
540 | dp->proc_iops = &proc_link_inode_operations; | |
541 | } else if (S_ISREG(dp->mode)) { | |
542 | if (dp->proc_fops == NULL) | |
543 | dp->proc_fops = &proc_file_operations; | |
544 | if (dp->proc_iops == NULL) | |
545 | dp->proc_iops = &proc_file_inode_operations; | |
546 | } | |
99fc06df CG |
547 | |
548 | spin_lock(&proc_subdir_lock); | |
94413d88 ZR |
549 | |
550 | for (tmp = dir->subdir; tmp; tmp = tmp->next) | |
551 | if (strcmp(tmp->name, dp->name) == 0) { | |
552 | printk(KERN_WARNING "proc_dir_entry '%s' already " | |
553 | "registered\n", dp->name); | |
554 | dump_stack(); | |
555 | break; | |
556 | } | |
557 | ||
99fc06df CG |
558 | dp->next = dir->subdir; |
559 | dp->parent = dir; | |
560 | dir->subdir = dp; | |
561 | spin_unlock(&proc_subdir_lock); | |
562 | ||
1da177e4 LT |
563 | return 0; |
564 | } | |
565 | ||
2d3a4e36 | 566 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 LT |
567 | const char *name, |
568 | mode_t mode, | |
569 | nlink_t nlink) | |
570 | { | |
571 | struct proc_dir_entry *ent = NULL; | |
572 | const char *fn = name; | |
573 | int len; | |
574 | ||
575 | /* make sure name is valid */ | |
576 | if (!name || !strlen(name)) goto out; | |
577 | ||
7cee4e00 | 578 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 LT |
579 | goto out; |
580 | ||
581 | /* At this point there must not be any '/' characters beyond *fn */ | |
582 | if (strchr(fn, '/')) | |
583 | goto out; | |
584 | ||
585 | len = strlen(fn); | |
586 | ||
587 | ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL); | |
588 | if (!ent) goto out; | |
589 | ||
590 | memset(ent, 0, sizeof(struct proc_dir_entry)); | |
591 | memcpy(((char *) ent) + sizeof(struct proc_dir_entry), fn, len + 1); | |
592 | ent->name = ((char *) ent) + sizeof(*ent); | |
593 | ent->namelen = len; | |
594 | ent->mode = mode; | |
595 | ent->nlink = nlink; | |
5a622f2d | 596 | atomic_set(&ent->count, 1); |
786d7e16 AD |
597 | ent->pde_users = 0; |
598 | spin_lock_init(&ent->pde_unload_lock); | |
599 | ent->pde_unload_completion = NULL; | |
881adb85 | 600 | INIT_LIST_HEAD(&ent->pde_openers); |
1da177e4 LT |
601 | out: |
602 | return ent; | |
603 | } | |
604 | ||
605 | struct proc_dir_entry *proc_symlink(const char *name, | |
606 | struct proc_dir_entry *parent, const char *dest) | |
607 | { | |
608 | struct proc_dir_entry *ent; | |
609 | ||
2d3a4e36 | 610 | ent = __proc_create(&parent, name, |
1da177e4 LT |
611 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
612 | ||
613 | if (ent) { | |
614 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
615 | if (ent->data) { | |
616 | strcpy((char*)ent->data,dest); | |
617 | if (proc_register(parent, ent) < 0) { | |
618 | kfree(ent->data); | |
619 | kfree(ent); | |
620 | ent = NULL; | |
621 | } | |
622 | } else { | |
623 | kfree(ent); | |
624 | ent = NULL; | |
625 | } | |
626 | } | |
627 | return ent; | |
628 | } | |
629 | ||
630 | struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode, | |
631 | struct proc_dir_entry *parent) | |
632 | { | |
633 | struct proc_dir_entry *ent; | |
634 | ||
2d3a4e36 | 635 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 636 | if (ent) { |
1da177e4 LT |
637 | if (proc_register(parent, ent) < 0) { |
638 | kfree(ent); | |
639 | ent = NULL; | |
640 | } | |
641 | } | |
642 | return ent; | |
643 | } | |
644 | ||
78e92b99 DL |
645 | struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name, |
646 | struct proc_dir_entry *parent) | |
647 | { | |
648 | struct proc_dir_entry *ent; | |
649 | ||
650 | ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2); | |
651 | if (ent) { | |
652 | ent->data = net; | |
653 | if (proc_register(parent, ent) < 0) { | |
654 | kfree(ent); | |
655 | ent = NULL; | |
656 | } | |
657 | } | |
658 | return ent; | |
659 | } | |
660 | EXPORT_SYMBOL_GPL(proc_net_mkdir); | |
661 | ||
1da177e4 LT |
662 | struct proc_dir_entry *proc_mkdir(const char *name, |
663 | struct proc_dir_entry *parent) | |
664 | { | |
665 | return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); | |
666 | } | |
667 | ||
668 | struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode, | |
669 | struct proc_dir_entry *parent) | |
670 | { | |
671 | struct proc_dir_entry *ent; | |
672 | nlink_t nlink; | |
673 | ||
674 | if (S_ISDIR(mode)) { | |
675 | if ((mode & S_IALLUGO) == 0) | |
676 | mode |= S_IRUGO | S_IXUGO; | |
677 | nlink = 2; | |
678 | } else { | |
679 | if ((mode & S_IFMT) == 0) | |
680 | mode |= S_IFREG; | |
681 | if ((mode & S_IALLUGO) == 0) | |
682 | mode |= S_IRUGO; | |
683 | nlink = 1; | |
684 | } | |
685 | ||
2d3a4e36 | 686 | ent = __proc_create(&parent, name, mode, nlink); |
1da177e4 | 687 | if (ent) { |
1da177e4 LT |
688 | if (proc_register(parent, ent) < 0) { |
689 | kfree(ent); | |
690 | ent = NULL; | |
691 | } | |
692 | } | |
693 | return ent; | |
694 | } | |
695 | ||
59b74351 DL |
696 | struct proc_dir_entry *proc_create_data(const char *name, mode_t mode, |
697 | struct proc_dir_entry *parent, | |
698 | const struct file_operations *proc_fops, | |
699 | void *data) | |
2d3a4e36 AD |
700 | { |
701 | struct proc_dir_entry *pde; | |
702 | nlink_t nlink; | |
703 | ||
704 | if (S_ISDIR(mode)) { | |
705 | if ((mode & S_IALLUGO) == 0) | |
706 | mode |= S_IRUGO | S_IXUGO; | |
707 | nlink = 2; | |
708 | } else { | |
709 | if ((mode & S_IFMT) == 0) | |
710 | mode |= S_IFREG; | |
711 | if ((mode & S_IALLUGO) == 0) | |
712 | mode |= S_IRUGO; | |
713 | nlink = 1; | |
714 | } | |
715 | ||
716 | pde = __proc_create(&parent, name, mode, nlink); | |
717 | if (!pde) | |
718 | goto out; | |
719 | pde->proc_fops = proc_fops; | |
59b74351 | 720 | pde->data = data; |
2d3a4e36 AD |
721 | if (proc_register(parent, pde) < 0) |
722 | goto out_free; | |
723 | return pde; | |
724 | out_free: | |
725 | kfree(pde); | |
726 | out: | |
727 | return NULL; | |
728 | } | |
729 | ||
1da177e4 LT |
730 | void free_proc_entry(struct proc_dir_entry *de) |
731 | { | |
732 | unsigned int ino = de->low_ino; | |
733 | ||
734 | if (ino < PROC_DYNAMIC_FIRST) | |
735 | return; | |
736 | ||
737 | release_inode_number(ino); | |
738 | ||
fd2cbe48 | 739 | if (S_ISLNK(de->mode)) |
1da177e4 LT |
740 | kfree(de->data); |
741 | kfree(de); | |
742 | } | |
743 | ||
744 | /* | |
745 | * Remove a /proc entry and free it if it's not currently in use. | |
1da177e4 LT |
746 | */ |
747 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
748 | { | |
749 | struct proc_dir_entry **p; | |
f649d6d3 | 750 | struct proc_dir_entry *de = NULL; |
1da177e4 LT |
751 | const char *fn = name; |
752 | int len; | |
753 | ||
7cee4e00 | 754 | if (xlate_proc_name(name, &parent, &fn) != 0) |
f649d6d3 | 755 | return; |
1da177e4 | 756 | len = strlen(fn); |
64a07bd8 SR |
757 | |
758 | spin_lock(&proc_subdir_lock); | |
1da177e4 | 759 | for (p = &parent->subdir; *p; p=&(*p)->next ) { |
f649d6d3 AD |
760 | if (proc_match(len, fn, *p)) { |
761 | de = *p; | |
762 | *p = de->next; | |
763 | de->next = NULL; | |
764 | break; | |
765 | } | |
766 | } | |
767 | spin_unlock(&proc_subdir_lock); | |
768 | if (!de) | |
769 | return; | |
786d7e16 | 770 | |
f649d6d3 AD |
771 | spin_lock(&de->pde_unload_lock); |
772 | /* | |
773 | * Stop accepting new callers into module. If you're | |
774 | * dynamically allocating ->proc_fops, save a pointer somewhere. | |
775 | */ | |
776 | de->proc_fops = NULL; | |
777 | /* Wait until all existing callers into module are done. */ | |
778 | if (de->pde_users > 0) { | |
779 | DECLARE_COMPLETION_ONSTACK(c); | |
780 | ||
781 | if (!de->pde_unload_completion) | |
782 | de->pde_unload_completion = &c; | |
786d7e16 | 783 | |
786d7e16 AD |
784 | spin_unlock(&de->pde_unload_lock); |
785 | ||
f649d6d3 AD |
786 | wait_for_completion(de->pde_unload_completion); |
787 | ||
788 | goto continue_removing; | |
789 | } | |
790 | spin_unlock(&de->pde_unload_lock); | |
791 | ||
786d7e16 | 792 | continue_removing: |
881adb85 AD |
793 | spin_lock(&de->pde_unload_lock); |
794 | while (!list_empty(&de->pde_openers)) { | |
795 | struct pde_opener *pdeo; | |
796 | ||
797 | pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh); | |
798 | list_del(&pdeo->lh); | |
799 | spin_unlock(&de->pde_unload_lock); | |
800 | pdeo->release(pdeo->inode, pdeo->file); | |
801 | kfree(pdeo); | |
802 | spin_lock(&de->pde_unload_lock); | |
803 | } | |
804 | spin_unlock(&de->pde_unload_lock); | |
805 | ||
f649d6d3 AD |
806 | if (S_ISDIR(de->mode)) |
807 | parent->nlink--; | |
808 | de->nlink = 0; | |
267e2a9c | 809 | WARN(de->subdir, KERN_WARNING "%s: removing non-empty directory " |
f649d6d3 AD |
810 | "'%s/%s', leaking at least '%s'\n", __func__, |
811 | de->parent->name, de->name, de->subdir->name); | |
f649d6d3 AD |
812 | if (atomic_dec_and_test(&de->count)) |
813 | free_proc_entry(de); | |
1da177e4 | 814 | } |