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 | ||
1da177e4 LT |
28 | static ssize_t proc_file_read(struct file *file, char __user *buf, |
29 | size_t nbytes, loff_t *ppos); | |
30 | static ssize_t proc_file_write(struct file *file, const char __user *buffer, | |
31 | size_t count, loff_t *ppos); | |
32 | static loff_t proc_file_lseek(struct file *, loff_t, int); | |
33 | ||
64a07bd8 SR |
34 | DEFINE_SPINLOCK(proc_subdir_lock); |
35 | ||
77b14db5 | 36 | static int proc_match(int len, const char *name, struct proc_dir_entry *de) |
1da177e4 LT |
37 | { |
38 | if (de->namelen != len) | |
39 | return 0; | |
40 | return !memcmp(name, de->name, len); | |
41 | } | |
42 | ||
00977a59 | 43 | static const struct file_operations proc_file_operations = { |
1da177e4 LT |
44 | .llseek = proc_file_lseek, |
45 | .read = proc_file_read, | |
46 | .write = proc_file_write, | |
47 | }; | |
48 | ||
49 | /* buffer size is one page but our output routines use some slack for overruns */ | |
50 | #define PROC_BLOCK_SIZE (PAGE_SIZE - 1024) | |
51 | ||
52 | static ssize_t | |
53 | proc_file_read(struct file *file, char __user *buf, size_t nbytes, | |
54 | loff_t *ppos) | |
55 | { | |
2fddfeef | 56 | struct inode * inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
57 | char *page; |
58 | ssize_t retval=0; | |
59 | int eof=0; | |
60 | ssize_t n, count; | |
61 | char *start; | |
62 | struct proc_dir_entry * dp; | |
8b90db0d LT |
63 | unsigned long long pos; |
64 | ||
65 | /* | |
66 | * Gaah, please just use "seq_file" instead. The legacy /proc | |
67 | * interfaces cut loff_t down to off_t for reads, and ignore | |
68 | * the offset entirely for writes.. | |
69 | */ | |
70 | pos = *ppos; | |
71 | if (pos > MAX_NON_LFS) | |
72 | return 0; | |
73 | if (nbytes > MAX_NON_LFS - pos) | |
74 | nbytes = MAX_NON_LFS - pos; | |
1da177e4 LT |
75 | |
76 | dp = PDE(inode); | |
e12ba74d | 77 | if (!(page = (char*) __get_free_page(GFP_TEMPORARY))) |
1da177e4 LT |
78 | return -ENOMEM; |
79 | ||
80 | while ((nbytes > 0) && !eof) { | |
81 | count = min_t(size_t, PROC_BLOCK_SIZE, nbytes); | |
82 | ||
83 | start = NULL; | |
84 | if (dp->get_info) { | |
85 | /* Handle old net routines */ | |
86 | n = dp->get_info(page, &start, *ppos, count); | |
87 | if (n < count) | |
88 | eof = 1; | |
89 | } else if (dp->read_proc) { | |
90 | /* | |
91 | * How to be a proc read function | |
92 | * ------------------------------ | |
93 | * Prototype: | |
94 | * int f(char *buffer, char **start, off_t offset, | |
95 | * int count, int *peof, void *dat) | |
96 | * | |
97 | * Assume that the buffer is "count" bytes in size. | |
98 | * | |
99 | * If you know you have supplied all the data you | |
100 | * have, set *peof. | |
101 | * | |
102 | * You have three ways to return data: | |
103 | * 0) Leave *start = NULL. (This is the default.) | |
104 | * Put the data of the requested offset at that | |
105 | * offset within the buffer. Return the number (n) | |
106 | * of bytes there are from the beginning of the | |
107 | * buffer up to the last byte of data. If the | |
108 | * number of supplied bytes (= n - offset) is | |
109 | * greater than zero and you didn't signal eof | |
110 | * and the reader is prepared to take more data | |
111 | * you will be called again with the requested | |
112 | * offset advanced by the number of bytes | |
113 | * absorbed. This interface is useful for files | |
114 | * no larger than the buffer. | |
115 | * 1) Set *start = an unsigned long value less than | |
116 | * the buffer address but greater than zero. | |
117 | * Put the data of the requested offset at the | |
118 | * beginning of the buffer. Return the number of | |
119 | * bytes of data placed there. If this number is | |
120 | * greater than zero and you didn't signal eof | |
121 | * and the reader is prepared to take more data | |
122 | * you will be called again with the requested | |
123 | * offset advanced by *start. This interface is | |
124 | * useful when you have a large file consisting | |
125 | * of a series of blocks which you want to count | |
126 | * and return as wholes. | |
127 | * (Hack by Paul.Russell@rustcorp.com.au) | |
128 | * 2) Set *start = an address within the buffer. | |
129 | * Put the data of the requested offset at *start. | |
130 | * Return the number of bytes of data placed there. | |
131 | * If this number is greater than zero and you | |
132 | * didn't signal eof and the reader is prepared to | |
133 | * take more data you will be called again with the | |
134 | * requested offset advanced by the number of bytes | |
135 | * absorbed. | |
136 | */ | |
137 | n = dp->read_proc(page, &start, *ppos, | |
138 | count, &eof, dp->data); | |
139 | } else | |
140 | break; | |
141 | ||
142 | if (n == 0) /* end of file */ | |
143 | break; | |
144 | if (n < 0) { /* error */ | |
145 | if (retval == 0) | |
146 | retval = n; | |
147 | break; | |
148 | } | |
149 | ||
150 | if (start == NULL) { | |
151 | if (n > PAGE_SIZE) { | |
152 | printk(KERN_ERR | |
153 | "proc_file_read: Apparent buffer overflow!\n"); | |
154 | n = PAGE_SIZE; | |
155 | } | |
156 | n -= *ppos; | |
157 | if (n <= 0) | |
158 | break; | |
159 | if (n > count) | |
160 | n = count; | |
161 | start = page + *ppos; | |
162 | } else if (start < page) { | |
163 | if (n > PAGE_SIZE) { | |
164 | printk(KERN_ERR | |
165 | "proc_file_read: Apparent buffer overflow!\n"); | |
166 | n = PAGE_SIZE; | |
167 | } | |
168 | if (n > count) { | |
169 | /* | |
170 | * Don't reduce n because doing so might | |
171 | * cut off part of a data block. | |
172 | */ | |
173 | printk(KERN_WARNING | |
174 | "proc_file_read: Read count exceeded\n"); | |
175 | } | |
176 | } else /* start >= page */ { | |
177 | unsigned long startoff = (unsigned long)(start - page); | |
178 | if (n > (PAGE_SIZE - startoff)) { | |
179 | printk(KERN_ERR | |
180 | "proc_file_read: Apparent buffer overflow!\n"); | |
181 | n = PAGE_SIZE - startoff; | |
182 | } | |
183 | if (n > count) | |
184 | n = count; | |
185 | } | |
186 | ||
187 | n -= copy_to_user(buf, start < page ? page : start, n); | |
188 | if (n == 0) { | |
189 | if (retval == 0) | |
190 | retval = -EFAULT; | |
191 | break; | |
192 | } | |
193 | ||
194 | *ppos += start < page ? (unsigned long)start : n; | |
195 | nbytes -= n; | |
196 | buf += n; | |
197 | retval += n; | |
198 | } | |
199 | free_page((unsigned long) page); | |
200 | return retval; | |
201 | } | |
202 | ||
203 | static ssize_t | |
204 | proc_file_write(struct file *file, const char __user *buffer, | |
205 | size_t count, loff_t *ppos) | |
206 | { | |
2fddfeef | 207 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
208 | struct proc_dir_entry * dp; |
209 | ||
210 | dp = PDE(inode); | |
211 | ||
212 | if (!dp->write_proc) | |
213 | return -EIO; | |
214 | ||
215 | /* FIXME: does this routine need ppos? probably... */ | |
216 | return dp->write_proc(file, buffer, count, dp->data); | |
217 | } | |
218 | ||
219 | ||
220 | static loff_t | |
221 | proc_file_lseek(struct file *file, loff_t offset, int orig) | |
222 | { | |
8b90db0d LT |
223 | loff_t retval = -EINVAL; |
224 | switch (orig) { | |
225 | case 1: | |
226 | offset += file->f_pos; | |
227 | /* fallthrough */ | |
228 | case 0: | |
229 | if (offset < 0 || offset > MAX_NON_LFS) | |
230 | break; | |
231 | file->f_pos = retval = offset; | |
232 | } | |
233 | return retval; | |
1da177e4 LT |
234 | } |
235 | ||
236 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) | |
237 | { | |
238 | struct inode *inode = dentry->d_inode; | |
239 | struct proc_dir_entry *de = PDE(inode); | |
240 | int error; | |
241 | ||
242 | error = inode_change_ok(inode, iattr); | |
243 | if (error) | |
244 | goto out; | |
245 | ||
246 | error = inode_setattr(inode, iattr); | |
247 | if (error) | |
248 | goto out; | |
249 | ||
250 | de->uid = inode->i_uid; | |
251 | de->gid = inode->i_gid; | |
252 | de->mode = inode->i_mode; | |
253 | out: | |
254 | return error; | |
255 | } | |
256 | ||
2b579bee MS |
257 | static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry, |
258 | struct kstat *stat) | |
259 | { | |
260 | struct inode *inode = dentry->d_inode; | |
261 | struct proc_dir_entry *de = PROC_I(inode)->pde; | |
262 | if (de && de->nlink) | |
263 | inode->i_nlink = de->nlink; | |
264 | ||
265 | generic_fillattr(inode, stat); | |
266 | return 0; | |
267 | } | |
268 | ||
c5ef1c42 | 269 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
270 | .setattr = proc_notify_change, |
271 | }; | |
272 | ||
273 | /* | |
274 | * This function parses a name such as "tty/driver/serial", and | |
275 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
276 | * returns "serial" in residual. | |
277 | */ | |
278 | static int xlate_proc_name(const char *name, | |
279 | struct proc_dir_entry **ret, const char **residual) | |
280 | { | |
281 | const char *cp = name, *next; | |
282 | struct proc_dir_entry *de; | |
283 | int len; | |
64a07bd8 | 284 | int rtn = 0; |
1da177e4 | 285 | |
64a07bd8 | 286 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
287 | de = &proc_root; |
288 | while (1) { | |
289 | next = strchr(cp, '/'); | |
290 | if (!next) | |
291 | break; | |
292 | ||
293 | len = next - cp; | |
294 | for (de = de->subdir; de ; de = de->next) { | |
295 | if (proc_match(len, cp, de)) | |
296 | break; | |
297 | } | |
64a07bd8 SR |
298 | if (!de) { |
299 | rtn = -ENOENT; | |
300 | goto out; | |
301 | } | |
1da177e4 LT |
302 | cp += len + 1; |
303 | } | |
304 | *residual = cp; | |
305 | *ret = de; | |
64a07bd8 SR |
306 | out: |
307 | spin_unlock(&proc_subdir_lock); | |
308 | return rtn; | |
1da177e4 LT |
309 | } |
310 | ||
311 | static DEFINE_IDR(proc_inum_idr); | |
312 | static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ | |
313 | ||
314 | #define PROC_DYNAMIC_FIRST 0xF0000000UL | |
315 | ||
316 | /* | |
317 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
318 | * 0xffffffff, or zero on failure. | |
319 | */ | |
320 | static unsigned int get_inode_number(void) | |
321 | { | |
322 | int i, inum = 0; | |
323 | int error; | |
324 | ||
325 | retry: | |
326 | if (idr_pre_get(&proc_inum_idr, GFP_KERNEL) == 0) | |
327 | return 0; | |
328 | ||
329 | spin_lock(&proc_inum_lock); | |
330 | error = idr_get_new(&proc_inum_idr, NULL, &i); | |
331 | spin_unlock(&proc_inum_lock); | |
332 | if (error == -EAGAIN) | |
333 | goto retry; | |
334 | else if (error) | |
335 | return 0; | |
336 | ||
337 | inum = (i & MAX_ID_MASK) + PROC_DYNAMIC_FIRST; | |
338 | ||
339 | /* inum will never be more than 0xf0ffffff, so no check | |
340 | * for overflow. | |
341 | */ | |
342 | ||
343 | return inum; | |
344 | } | |
345 | ||
346 | static void release_inode_number(unsigned int inum) | |
347 | { | |
348 | int id = (inum - PROC_DYNAMIC_FIRST) | ~MAX_ID_MASK; | |
349 | ||
350 | spin_lock(&proc_inum_lock); | |
351 | idr_remove(&proc_inum_idr, id); | |
352 | spin_unlock(&proc_inum_lock); | |
353 | } | |
354 | ||
008b150a | 355 | static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
356 | { |
357 | nd_set_link(nd, PDE(dentry->d_inode)->data); | |
008b150a | 358 | return NULL; |
1da177e4 LT |
359 | } |
360 | ||
c5ef1c42 | 361 | static const struct inode_operations proc_link_inode_operations = { |
1da177e4 LT |
362 | .readlink = generic_readlink, |
363 | .follow_link = proc_follow_link, | |
364 | }; | |
365 | ||
366 | /* | |
367 | * As some entries in /proc are volatile, we want to | |
368 | * get rid of unused dentries. This could be made | |
369 | * smarter: we could keep a "volatile" flag in the | |
370 | * inode to indicate which ones to keep. | |
371 | */ | |
372 | static int proc_delete_dentry(struct dentry * dentry) | |
373 | { | |
374 | return 1; | |
375 | } | |
376 | ||
377 | static struct dentry_operations proc_dentry_operations = | |
378 | { | |
379 | .d_delete = proc_delete_dentry, | |
380 | }; | |
381 | ||
382 | /* | |
383 | * Don't create negative dentries here, return -ENOENT by hand | |
384 | * instead. | |
385 | */ | |
386 | struct dentry *proc_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) | |
387 | { | |
388 | struct inode *inode = NULL; | |
389 | struct proc_dir_entry * de; | |
390 | int error = -ENOENT; | |
391 | ||
392 | lock_kernel(); | |
64a07bd8 | 393 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
394 | de = PDE(dir); |
395 | if (de) { | |
396 | for (de = de->subdir; de ; de = de->next) { | |
397 | if (de->namelen != dentry->d_name.len) | |
398 | continue; | |
399 | if (!memcmp(dentry->d_name.name, de->name, de->namelen)) { | |
2b1e300a | 400 | unsigned int ino; |
1da177e4 | 401 | |
2b1e300a EB |
402 | if (de->shadow_proc) |
403 | de = de->shadow_proc(current, de); | |
404 | ino = de->low_ino; | |
7695650a | 405 | de_get(de); |
64a07bd8 | 406 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
407 | error = -EINVAL; |
408 | inode = proc_get_inode(dir->i_sb, ino, de); | |
4237e0d3 | 409 | goto out_unlock; |
1da177e4 LT |
410 | } |
411 | } | |
412 | } | |
64a07bd8 | 413 | spin_unlock(&proc_subdir_lock); |
4237e0d3 | 414 | out_unlock: |
1da177e4 LT |
415 | unlock_kernel(); |
416 | ||
417 | if (inode) { | |
418 | dentry->d_op = &proc_dentry_operations; | |
419 | d_add(dentry, inode); | |
420 | return NULL; | |
421 | } | |
7695650a | 422 | de_put(de); |
1da177e4 LT |
423 | return ERR_PTR(error); |
424 | } | |
425 | ||
426 | /* | |
427 | * This returns non-zero if at EOF, so that the /proc | |
428 | * root directory can use this and check if it should | |
429 | * continue with the <pid> entries.. | |
430 | * | |
431 | * Note that the VFS-layer doesn't care about the return | |
432 | * value of the readdir() call, as long as it's non-negative | |
433 | * for success.. | |
434 | */ | |
435 | int proc_readdir(struct file * filp, | |
436 | void * dirent, filldir_t filldir) | |
437 | { | |
438 | struct proc_dir_entry * de; | |
439 | unsigned int ino; | |
440 | int i; | |
2fddfeef | 441 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
442 | int ret = 0; |
443 | ||
444 | lock_kernel(); | |
445 | ||
446 | ino = inode->i_ino; | |
447 | de = PDE(inode); | |
448 | if (!de) { | |
449 | ret = -EINVAL; | |
450 | goto out; | |
451 | } | |
452 | i = filp->f_pos; | |
453 | switch (i) { | |
454 | case 0: | |
455 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
456 | goto out; | |
457 | i++; | |
458 | filp->f_pos++; | |
459 | /* fall through */ | |
460 | case 1: | |
461 | if (filldir(dirent, "..", 2, i, | |
2fddfeef | 462 | parent_ino(filp->f_path.dentry), |
1da177e4 LT |
463 | DT_DIR) < 0) |
464 | goto out; | |
465 | i++; | |
466 | filp->f_pos++; | |
467 | /* fall through */ | |
468 | default: | |
64a07bd8 | 469 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
470 | de = de->subdir; |
471 | i -= 2; | |
472 | for (;;) { | |
473 | if (!de) { | |
474 | ret = 1; | |
64a07bd8 | 475 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
476 | goto out; |
477 | } | |
478 | if (!i) | |
479 | break; | |
480 | de = de->next; | |
481 | i--; | |
482 | } | |
483 | ||
484 | do { | |
59cd0cbc DW |
485 | struct proc_dir_entry *next; |
486 | ||
64a07bd8 | 487 | /* filldir passes info to user space */ |
59cd0cbc | 488 | de_get(de); |
64a07bd8 | 489 | spin_unlock(&proc_subdir_lock); |
1da177e4 | 490 | if (filldir(dirent, de->name, de->namelen, filp->f_pos, |
59cd0cbc DW |
491 | de->low_ino, de->mode >> 12) < 0) { |
492 | de_put(de); | |
1da177e4 | 493 | goto out; |
59cd0cbc | 494 | } |
64a07bd8 | 495 | spin_lock(&proc_subdir_lock); |
1da177e4 | 496 | filp->f_pos++; |
59cd0cbc DW |
497 | next = de->next; |
498 | de_put(de); | |
499 | de = next; | |
1da177e4 | 500 | } while (de); |
64a07bd8 | 501 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
502 | } |
503 | ret = 1; | |
504 | out: unlock_kernel(); | |
505 | return ret; | |
506 | } | |
507 | ||
508 | /* | |
509 | * These are the generic /proc directory operations. They | |
510 | * use the in-memory "struct proc_dir_entry" tree to parse | |
511 | * the /proc directory. | |
512 | */ | |
00977a59 | 513 | static const struct file_operations proc_dir_operations = { |
1da177e4 LT |
514 | .read = generic_read_dir, |
515 | .readdir = proc_readdir, | |
516 | }; | |
517 | ||
518 | /* | |
519 | * proc directories can do almost nothing.. | |
520 | */ | |
c5ef1c42 | 521 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 522 | .lookup = proc_lookup, |
2b579bee | 523 | .getattr = proc_getattr, |
1da177e4 LT |
524 | .setattr = proc_notify_change, |
525 | }; | |
526 | ||
527 | static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) | |
528 | { | |
529 | unsigned int i; | |
530 | ||
531 | i = get_inode_number(); | |
532 | if (i == 0) | |
533 | return -EAGAIN; | |
534 | dp->low_ino = i; | |
64a07bd8 | 535 | |
1da177e4 LT |
536 | if (S_ISDIR(dp->mode)) { |
537 | if (dp->proc_iops == NULL) { | |
538 | dp->proc_fops = &proc_dir_operations; | |
539 | dp->proc_iops = &proc_dir_inode_operations; | |
540 | } | |
541 | dir->nlink++; | |
542 | } else if (S_ISLNK(dp->mode)) { | |
543 | if (dp->proc_iops == NULL) | |
544 | dp->proc_iops = &proc_link_inode_operations; | |
545 | } else if (S_ISREG(dp->mode)) { | |
546 | if (dp->proc_fops == NULL) | |
547 | dp->proc_fops = &proc_file_operations; | |
548 | if (dp->proc_iops == NULL) | |
549 | dp->proc_iops = &proc_file_inode_operations; | |
550 | } | |
99fc06df CG |
551 | |
552 | spin_lock(&proc_subdir_lock); | |
553 | dp->next = dir->subdir; | |
554 | dp->parent = dir; | |
555 | dir->subdir = dp; | |
556 | spin_unlock(&proc_subdir_lock); | |
557 | ||
1da177e4 LT |
558 | return 0; |
559 | } | |
560 | ||
1da177e4 LT |
561 | static struct proc_dir_entry *proc_create(struct proc_dir_entry **parent, |
562 | const char *name, | |
563 | mode_t mode, | |
564 | nlink_t nlink) | |
565 | { | |
566 | struct proc_dir_entry *ent = NULL; | |
567 | const char *fn = name; | |
568 | int len; | |
569 | ||
570 | /* make sure name is valid */ | |
571 | if (!name || !strlen(name)) goto out; | |
572 | ||
573 | if (!(*parent) && xlate_proc_name(name, parent, &fn) != 0) | |
574 | goto out; | |
575 | ||
576 | /* At this point there must not be any '/' characters beyond *fn */ | |
577 | if (strchr(fn, '/')) | |
578 | goto out; | |
579 | ||
580 | len = strlen(fn); | |
581 | ||
582 | ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL); | |
583 | if (!ent) goto out; | |
584 | ||
585 | memset(ent, 0, sizeof(struct proc_dir_entry)); | |
586 | memcpy(((char *) ent) + sizeof(struct proc_dir_entry), fn, len + 1); | |
587 | ent->name = ((char *) ent) + sizeof(*ent); | |
588 | ent->namelen = len; | |
589 | ent->mode = mode; | |
590 | ent->nlink = nlink; | |
5a622f2d | 591 | atomic_set(&ent->count, 1); |
786d7e16 AD |
592 | ent->pde_users = 0; |
593 | spin_lock_init(&ent->pde_unload_lock); | |
594 | ent->pde_unload_completion = NULL; | |
1da177e4 LT |
595 | out: |
596 | return ent; | |
597 | } | |
598 | ||
599 | struct proc_dir_entry *proc_symlink(const char *name, | |
600 | struct proc_dir_entry *parent, const char *dest) | |
601 | { | |
602 | struct proc_dir_entry *ent; | |
603 | ||
604 | ent = proc_create(&parent,name, | |
605 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); | |
606 | ||
607 | if (ent) { | |
608 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
609 | if (ent->data) { | |
610 | strcpy((char*)ent->data,dest); | |
611 | if (proc_register(parent, ent) < 0) { | |
612 | kfree(ent->data); | |
613 | kfree(ent); | |
614 | ent = NULL; | |
615 | } | |
616 | } else { | |
617 | kfree(ent); | |
618 | ent = NULL; | |
619 | } | |
620 | } | |
621 | return ent; | |
622 | } | |
623 | ||
624 | struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode, | |
625 | struct proc_dir_entry *parent) | |
626 | { | |
627 | struct proc_dir_entry *ent; | |
628 | ||
629 | ent = proc_create(&parent, name, S_IFDIR | mode, 2); | |
630 | if (ent) { | |
1da177e4 LT |
631 | if (proc_register(parent, ent) < 0) { |
632 | kfree(ent); | |
633 | ent = NULL; | |
634 | } | |
635 | } | |
636 | return ent; | |
637 | } | |
638 | ||
639 | struct proc_dir_entry *proc_mkdir(const char *name, | |
640 | struct proc_dir_entry *parent) | |
641 | { | |
642 | return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); | |
643 | } | |
644 | ||
645 | struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode, | |
646 | struct proc_dir_entry *parent) | |
647 | { | |
648 | struct proc_dir_entry *ent; | |
649 | nlink_t nlink; | |
650 | ||
651 | if (S_ISDIR(mode)) { | |
652 | if ((mode & S_IALLUGO) == 0) | |
653 | mode |= S_IRUGO | S_IXUGO; | |
654 | nlink = 2; | |
655 | } else { | |
656 | if ((mode & S_IFMT) == 0) | |
657 | mode |= S_IFREG; | |
658 | if ((mode & S_IALLUGO) == 0) | |
659 | mode |= S_IRUGO; | |
660 | nlink = 1; | |
661 | } | |
662 | ||
663 | ent = proc_create(&parent,name,mode,nlink); | |
664 | if (ent) { | |
1da177e4 LT |
665 | if (proc_register(parent, ent) < 0) { |
666 | kfree(ent); | |
667 | ent = NULL; | |
668 | } | |
669 | } | |
670 | return ent; | |
671 | } | |
672 | ||
673 | void free_proc_entry(struct proc_dir_entry *de) | |
674 | { | |
675 | unsigned int ino = de->low_ino; | |
676 | ||
677 | if (ino < PROC_DYNAMIC_FIRST) | |
678 | return; | |
679 | ||
680 | release_inode_number(ino); | |
681 | ||
682 | if (S_ISLNK(de->mode) && de->data) | |
683 | kfree(de->data); | |
684 | kfree(de); | |
685 | } | |
686 | ||
687 | /* | |
688 | * Remove a /proc entry and free it if it's not currently in use. | |
1da177e4 LT |
689 | */ |
690 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
691 | { | |
692 | struct proc_dir_entry **p; | |
693 | struct proc_dir_entry *de; | |
694 | const char *fn = name; | |
695 | int len; | |
696 | ||
697 | if (!parent && xlate_proc_name(name, &parent, &fn) != 0) | |
698 | goto out; | |
699 | len = strlen(fn); | |
64a07bd8 SR |
700 | |
701 | spin_lock(&proc_subdir_lock); | |
1da177e4 LT |
702 | for (p = &parent->subdir; *p; p=&(*p)->next ) { |
703 | if (!proc_match(len, fn, *p)) | |
704 | continue; | |
705 | de = *p; | |
706 | *p = de->next; | |
707 | de->next = NULL; | |
786d7e16 AD |
708 | |
709 | spin_lock(&de->pde_unload_lock); | |
710 | /* | |
711 | * Stop accepting new callers into module. If you're | |
712 | * dynamically allocating ->proc_fops, save a pointer somewhere. | |
713 | */ | |
714 | de->proc_fops = NULL; | |
715 | /* Wait until all existing callers into module are done. */ | |
716 | if (de->pde_users > 0) { | |
717 | DECLARE_COMPLETION_ONSTACK(c); | |
718 | ||
719 | if (!de->pde_unload_completion) | |
720 | de->pde_unload_completion = &c; | |
721 | ||
722 | spin_unlock(&de->pde_unload_lock); | |
723 | spin_unlock(&proc_subdir_lock); | |
724 | ||
725 | wait_for_completion(de->pde_unload_completion); | |
726 | ||
727 | spin_lock(&proc_subdir_lock); | |
728 | goto continue_removing; | |
729 | } | |
730 | spin_unlock(&de->pde_unload_lock); | |
731 | ||
732 | continue_removing: | |
1da177e4 LT |
733 | if (S_ISDIR(de->mode)) |
734 | parent->nlink--; | |
1da177e4 LT |
735 | de->nlink = 0; |
736 | WARN_ON(de->subdir); | |
5a622f2d | 737 | if (atomic_dec_and_test(&de->count)) |
1da177e4 | 738 | free_proc_entry(de); |
1da177e4 LT |
739 | break; |
740 | } | |
64a07bd8 | 741 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
742 | out: |
743 | return; | |
744 | } |