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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> | |
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; | |
72 | if (dp->get_info) { | |
73 | /* Handle old net routines */ | |
74 | n = dp->get_info(page, &start, *ppos, count); | |
75 | if (n < count) | |
76 | eof = 1; | |
77 | } else if (dp->read_proc) { | |
78 | /* | |
79 | * How to be a proc read function | |
80 | * ------------------------------ | |
81 | * Prototype: | |
82 | * int f(char *buffer, char **start, off_t offset, | |
83 | * int count, int *peof, void *dat) | |
84 | * | |
85 | * Assume that the buffer is "count" bytes in size. | |
86 | * | |
87 | * If you know you have supplied all the data you | |
88 | * have, set *peof. | |
89 | * | |
90 | * You have three ways to return data: | |
91 | * 0) Leave *start = NULL. (This is the default.) | |
92 | * Put the data of the requested offset at that | |
93 | * offset within the buffer. Return the number (n) | |
94 | * of bytes there are from the beginning of the | |
95 | * buffer up to the last byte of data. If the | |
96 | * number of supplied bytes (= n - offset) is | |
97 | * greater than zero and you didn't signal eof | |
98 | * and the reader is prepared to take more data | |
99 | * you will be called again with the requested | |
100 | * offset advanced by the number of bytes | |
101 | * absorbed. This interface is useful for files | |
102 | * no larger than the buffer. | |
103 | * 1) Set *start = an unsigned long value less than | |
104 | * the buffer address but greater than zero. | |
105 | * Put the data of the requested offset at the | |
106 | * beginning of the buffer. Return the number of | |
107 | * bytes of data placed there. If this number is | |
108 | * greater than zero and you didn't signal eof | |
109 | * and the reader is prepared to take more data | |
110 | * you will be called again with the requested | |
111 | * offset advanced by *start. This interface is | |
112 | * useful when you have a large file consisting | |
113 | * of a series of blocks which you want to count | |
114 | * and return as wholes. | |
115 | * (Hack by Paul.Russell@rustcorp.com.au) | |
116 | * 2) Set *start = an address within the buffer. | |
117 | * Put the data of the requested offset at *start. | |
118 | * Return the number of bytes of data placed there. | |
119 | * If this number is greater than zero and you | |
120 | * didn't signal eof and the reader is prepared to | |
121 | * take more data you will be called again with the | |
122 | * requested offset advanced by the number of bytes | |
123 | * absorbed. | |
124 | */ | |
125 | n = dp->read_proc(page, &start, *ppos, | |
126 | count, &eof, dp->data); | |
127 | } else | |
128 | break; | |
129 | ||
130 | if (n == 0) /* end of file */ | |
131 | break; | |
132 | if (n < 0) { /* error */ | |
133 | if (retval == 0) | |
134 | retval = n; | |
135 | break; | |
136 | } | |
137 | ||
138 | if (start == NULL) { | |
139 | if (n > PAGE_SIZE) { | |
140 | printk(KERN_ERR | |
141 | "proc_file_read: Apparent buffer overflow!\n"); | |
142 | n = PAGE_SIZE; | |
143 | } | |
144 | n -= *ppos; | |
145 | if (n <= 0) | |
146 | break; | |
147 | if (n > count) | |
148 | n = count; | |
149 | start = page + *ppos; | |
150 | } else if (start < page) { | |
151 | if (n > PAGE_SIZE) { | |
152 | printk(KERN_ERR | |
153 | "proc_file_read: Apparent buffer overflow!\n"); | |
154 | n = PAGE_SIZE; | |
155 | } | |
156 | if (n > count) { | |
157 | /* | |
158 | * Don't reduce n because doing so might | |
159 | * cut off part of a data block. | |
160 | */ | |
161 | printk(KERN_WARNING | |
162 | "proc_file_read: Read count exceeded\n"); | |
163 | } | |
164 | } else /* start >= page */ { | |
165 | unsigned long startoff = (unsigned long)(start - page); | |
166 | if (n > (PAGE_SIZE - startoff)) { | |
167 | printk(KERN_ERR | |
168 | "proc_file_read: Apparent buffer overflow!\n"); | |
169 | n = PAGE_SIZE - startoff; | |
170 | } | |
171 | if (n > count) | |
172 | n = count; | |
173 | } | |
174 | ||
175 | n -= copy_to_user(buf, start < page ? page : start, n); | |
176 | if (n == 0) { | |
177 | if (retval == 0) | |
178 | retval = -EFAULT; | |
179 | break; | |
180 | } | |
181 | ||
182 | *ppos += start < page ? (unsigned long)start : n; | |
183 | nbytes -= n; | |
184 | buf += n; | |
185 | retval += n; | |
186 | } | |
187 | free_page((unsigned long) page); | |
188 | return retval; | |
189 | } | |
190 | ||
191 | static ssize_t | |
192 | proc_file_write(struct file *file, const char __user *buffer, | |
193 | size_t count, loff_t *ppos) | |
194 | { | |
2fddfeef | 195 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
196 | struct proc_dir_entry * dp; |
197 | ||
198 | dp = PDE(inode); | |
199 | ||
200 | if (!dp->write_proc) | |
201 | return -EIO; | |
202 | ||
203 | /* FIXME: does this routine need ppos? probably... */ | |
204 | return dp->write_proc(file, buffer, count, dp->data); | |
205 | } | |
206 | ||
207 | ||
208 | static loff_t | |
209 | proc_file_lseek(struct file *file, loff_t offset, int orig) | |
210 | { | |
8b90db0d LT |
211 | loff_t retval = -EINVAL; |
212 | switch (orig) { | |
213 | case 1: | |
214 | offset += file->f_pos; | |
215 | /* fallthrough */ | |
216 | case 0: | |
217 | if (offset < 0 || offset > MAX_NON_LFS) | |
218 | break; | |
219 | file->f_pos = retval = offset; | |
220 | } | |
221 | return retval; | |
1da177e4 LT |
222 | } |
223 | ||
76df0c25 AD |
224 | static const struct file_operations proc_file_operations = { |
225 | .llseek = proc_file_lseek, | |
226 | .read = proc_file_read, | |
227 | .write = proc_file_write, | |
228 | }; | |
229 | ||
1da177e4 LT |
230 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) |
231 | { | |
232 | struct inode *inode = dentry->d_inode; | |
233 | struct proc_dir_entry *de = PDE(inode); | |
234 | int error; | |
235 | ||
236 | error = inode_change_ok(inode, iattr); | |
237 | if (error) | |
238 | goto out; | |
239 | ||
240 | error = inode_setattr(inode, iattr); | |
241 | if (error) | |
242 | goto out; | |
243 | ||
244 | de->uid = inode->i_uid; | |
245 | de->gid = inode->i_gid; | |
246 | de->mode = inode->i_mode; | |
247 | out: | |
248 | return error; | |
249 | } | |
250 | ||
2b579bee MS |
251 | static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry, |
252 | struct kstat *stat) | |
253 | { | |
254 | struct inode *inode = dentry->d_inode; | |
255 | struct proc_dir_entry *de = PROC_I(inode)->pde; | |
256 | if (de && de->nlink) | |
257 | inode->i_nlink = de->nlink; | |
258 | ||
259 | generic_fillattr(inode, stat); | |
260 | return 0; | |
261 | } | |
262 | ||
c5ef1c42 | 263 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
264 | .setattr = proc_notify_change, |
265 | }; | |
266 | ||
267 | /* | |
268 | * This function parses a name such as "tty/driver/serial", and | |
269 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
270 | * returns "serial" in residual. | |
271 | */ | |
272 | static int xlate_proc_name(const char *name, | |
273 | struct proc_dir_entry **ret, const char **residual) | |
274 | { | |
275 | const char *cp = name, *next; | |
276 | struct proc_dir_entry *de; | |
277 | int len; | |
64a07bd8 | 278 | int rtn = 0; |
1da177e4 | 279 | |
64a07bd8 | 280 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
281 | de = &proc_root; |
282 | while (1) { | |
283 | next = strchr(cp, '/'); | |
284 | if (!next) | |
285 | break; | |
286 | ||
287 | len = next - cp; | |
288 | for (de = de->subdir; de ; de = de->next) { | |
289 | if (proc_match(len, cp, de)) | |
290 | break; | |
291 | } | |
64a07bd8 SR |
292 | if (!de) { |
293 | rtn = -ENOENT; | |
294 | goto out; | |
295 | } | |
1da177e4 LT |
296 | cp += len + 1; |
297 | } | |
298 | *residual = cp; | |
299 | *ret = de; | |
64a07bd8 SR |
300 | out: |
301 | spin_unlock(&proc_subdir_lock); | |
302 | return rtn; | |
1da177e4 LT |
303 | } |
304 | ||
305 | static DEFINE_IDR(proc_inum_idr); | |
306 | static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ | |
307 | ||
308 | #define PROC_DYNAMIC_FIRST 0xF0000000UL | |
309 | ||
310 | /* | |
311 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
312 | * 0xffffffff, or zero on failure. | |
313 | */ | |
314 | static unsigned int get_inode_number(void) | |
315 | { | |
316 | int i, inum = 0; | |
317 | int error; | |
318 | ||
319 | retry: | |
320 | if (idr_pre_get(&proc_inum_idr, GFP_KERNEL) == 0) | |
321 | return 0; | |
322 | ||
323 | spin_lock(&proc_inum_lock); | |
324 | error = idr_get_new(&proc_inum_idr, NULL, &i); | |
325 | spin_unlock(&proc_inum_lock); | |
326 | if (error == -EAGAIN) | |
327 | goto retry; | |
328 | else if (error) | |
329 | return 0; | |
330 | ||
331 | inum = (i & MAX_ID_MASK) + PROC_DYNAMIC_FIRST; | |
332 | ||
333 | /* inum will never be more than 0xf0ffffff, so no check | |
334 | * for overflow. | |
335 | */ | |
336 | ||
337 | return inum; | |
338 | } | |
339 | ||
340 | static void release_inode_number(unsigned int inum) | |
341 | { | |
342 | int id = (inum - PROC_DYNAMIC_FIRST) | ~MAX_ID_MASK; | |
343 | ||
344 | spin_lock(&proc_inum_lock); | |
345 | idr_remove(&proc_inum_idr, id); | |
346 | spin_unlock(&proc_inum_lock); | |
347 | } | |
348 | ||
008b150a | 349 | static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
350 | { |
351 | nd_set_link(nd, PDE(dentry->d_inode)->data); | |
008b150a | 352 | return NULL; |
1da177e4 LT |
353 | } |
354 | ||
c5ef1c42 | 355 | static const struct inode_operations proc_link_inode_operations = { |
1da177e4 LT |
356 | .readlink = generic_readlink, |
357 | .follow_link = proc_follow_link, | |
358 | }; | |
359 | ||
360 | /* | |
361 | * As some entries in /proc are volatile, we want to | |
362 | * get rid of unused dentries. This could be made | |
363 | * smarter: we could keep a "volatile" flag in the | |
364 | * inode to indicate which ones to keep. | |
365 | */ | |
366 | static int proc_delete_dentry(struct dentry * dentry) | |
367 | { | |
368 | return 1; | |
369 | } | |
370 | ||
371 | static struct dentry_operations proc_dentry_operations = | |
372 | { | |
373 | .d_delete = proc_delete_dentry, | |
374 | }; | |
375 | ||
376 | /* | |
377 | * Don't create negative dentries here, return -ENOENT by hand | |
378 | * instead. | |
379 | */ | |
e9720acd PE |
380 | struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir, |
381 | struct dentry *dentry) | |
1da177e4 LT |
382 | { |
383 | struct inode *inode = NULL; | |
1da177e4 LT |
384 | int error = -ENOENT; |
385 | ||
386 | lock_kernel(); | |
64a07bd8 | 387 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
388 | if (de) { |
389 | for (de = de->subdir; de ; de = de->next) { | |
390 | if (de->namelen != dentry->d_name.len) | |
391 | continue; | |
392 | if (!memcmp(dentry->d_name.name, de->name, de->namelen)) { | |
2b1e300a | 393 | unsigned int ino; |
1da177e4 | 394 | |
2b1e300a | 395 | ino = de->low_ino; |
7695650a | 396 | de_get(de); |
64a07bd8 | 397 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
398 | error = -EINVAL; |
399 | inode = proc_get_inode(dir->i_sb, ino, de); | |
4237e0d3 | 400 | goto out_unlock; |
1da177e4 LT |
401 | } |
402 | } | |
403 | } | |
64a07bd8 | 404 | spin_unlock(&proc_subdir_lock); |
4237e0d3 | 405 | out_unlock: |
1da177e4 LT |
406 | unlock_kernel(); |
407 | ||
408 | if (inode) { | |
409 | dentry->d_op = &proc_dentry_operations; | |
410 | d_add(dentry, inode); | |
411 | return NULL; | |
412 | } | |
7695650a | 413 | de_put(de); |
1da177e4 LT |
414 | return ERR_PTR(error); |
415 | } | |
416 | ||
e9720acd PE |
417 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
418 | struct nameidata *nd) | |
419 | { | |
420 | return proc_lookup_de(PDE(dir), dir, dentry); | |
421 | } | |
422 | ||
1da177e4 LT |
423 | /* |
424 | * This returns non-zero if at EOF, so that the /proc | |
425 | * root directory can use this and check if it should | |
426 | * continue with the <pid> entries.. | |
427 | * | |
428 | * Note that the VFS-layer doesn't care about the return | |
429 | * value of the readdir() call, as long as it's non-negative | |
430 | * for success.. | |
431 | */ | |
e9720acd PE |
432 | int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent, |
433 | filldir_t filldir) | |
1da177e4 | 434 | { |
1da177e4 LT |
435 | unsigned int ino; |
436 | int i; | |
2fddfeef | 437 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
438 | int ret = 0; |
439 | ||
440 | lock_kernel(); | |
441 | ||
442 | ino = inode->i_ino; | |
1da177e4 LT |
443 | if (!de) { |
444 | ret = -EINVAL; | |
445 | goto out; | |
446 | } | |
447 | i = filp->f_pos; | |
448 | switch (i) { | |
449 | case 0: | |
450 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
451 | goto out; | |
452 | i++; | |
453 | filp->f_pos++; | |
454 | /* fall through */ | |
455 | case 1: | |
456 | if (filldir(dirent, "..", 2, i, | |
2fddfeef | 457 | parent_ino(filp->f_path.dentry), |
1da177e4 LT |
458 | DT_DIR) < 0) |
459 | goto out; | |
460 | i++; | |
461 | filp->f_pos++; | |
462 | /* fall through */ | |
463 | default: | |
64a07bd8 | 464 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
465 | de = de->subdir; |
466 | i -= 2; | |
467 | for (;;) { | |
468 | if (!de) { | |
469 | ret = 1; | |
64a07bd8 | 470 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
471 | goto out; |
472 | } | |
473 | if (!i) | |
474 | break; | |
475 | de = de->next; | |
476 | i--; | |
477 | } | |
478 | ||
479 | do { | |
59cd0cbc DW |
480 | struct proc_dir_entry *next; |
481 | ||
64a07bd8 | 482 | /* filldir passes info to user space */ |
59cd0cbc | 483 | de_get(de); |
64a07bd8 | 484 | spin_unlock(&proc_subdir_lock); |
1da177e4 | 485 | if (filldir(dirent, de->name, de->namelen, filp->f_pos, |
59cd0cbc DW |
486 | de->low_ino, de->mode >> 12) < 0) { |
487 | de_put(de); | |
1da177e4 | 488 | goto out; |
59cd0cbc | 489 | } |
64a07bd8 | 490 | spin_lock(&proc_subdir_lock); |
1da177e4 | 491 | filp->f_pos++; |
59cd0cbc DW |
492 | next = de->next; |
493 | de_put(de); | |
494 | de = next; | |
1da177e4 | 495 | } while (de); |
64a07bd8 | 496 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
497 | } |
498 | ret = 1; | |
499 | out: unlock_kernel(); | |
500 | return ret; | |
501 | } | |
502 | ||
e9720acd PE |
503 | int proc_readdir(struct file *filp, void *dirent, filldir_t filldir) |
504 | { | |
505 | struct inode *inode = filp->f_path.dentry->d_inode; | |
506 | ||
507 | return proc_readdir_de(PDE(inode), filp, dirent, filldir); | |
508 | } | |
509 | ||
1da177e4 LT |
510 | /* |
511 | * These are the generic /proc directory operations. They | |
512 | * use the in-memory "struct proc_dir_entry" tree to parse | |
513 | * the /proc directory. | |
514 | */ | |
00977a59 | 515 | static const struct file_operations proc_dir_operations = { |
1da177e4 LT |
516 | .read = generic_read_dir, |
517 | .readdir = proc_readdir, | |
518 | }; | |
519 | ||
520 | /* | |
521 | * proc directories can do almost nothing.. | |
522 | */ | |
c5ef1c42 | 523 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 524 | .lookup = proc_lookup, |
2b579bee | 525 | .getattr = proc_getattr, |
1da177e4 LT |
526 | .setattr = proc_notify_change, |
527 | }; | |
528 | ||
529 | static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) | |
530 | { | |
531 | unsigned int i; | |
94413d88 | 532 | struct proc_dir_entry *tmp; |
1da177e4 LT |
533 | |
534 | i = get_inode_number(); | |
535 | if (i == 0) | |
536 | return -EAGAIN; | |
537 | dp->low_ino = i; | |
64a07bd8 | 538 | |
1da177e4 LT |
539 | if (S_ISDIR(dp->mode)) { |
540 | if (dp->proc_iops == NULL) { | |
541 | dp->proc_fops = &proc_dir_operations; | |
542 | dp->proc_iops = &proc_dir_inode_operations; | |
543 | } | |
544 | dir->nlink++; | |
545 | } else if (S_ISLNK(dp->mode)) { | |
546 | if (dp->proc_iops == NULL) | |
547 | dp->proc_iops = &proc_link_inode_operations; | |
548 | } else if (S_ISREG(dp->mode)) { | |
549 | if (dp->proc_fops == NULL) | |
550 | dp->proc_fops = &proc_file_operations; | |
551 | if (dp->proc_iops == NULL) | |
552 | dp->proc_iops = &proc_file_inode_operations; | |
553 | } | |
99fc06df CG |
554 | |
555 | spin_lock(&proc_subdir_lock); | |
94413d88 ZR |
556 | |
557 | for (tmp = dir->subdir; tmp; tmp = tmp->next) | |
558 | if (strcmp(tmp->name, dp->name) == 0) { | |
559 | printk(KERN_WARNING "proc_dir_entry '%s' already " | |
560 | "registered\n", dp->name); | |
561 | dump_stack(); | |
562 | break; | |
563 | } | |
564 | ||
99fc06df CG |
565 | dp->next = dir->subdir; |
566 | dp->parent = dir; | |
567 | dir->subdir = dp; | |
568 | spin_unlock(&proc_subdir_lock); | |
569 | ||
1da177e4 LT |
570 | return 0; |
571 | } | |
572 | ||
2d3a4e36 | 573 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 LT |
574 | const char *name, |
575 | mode_t mode, | |
576 | nlink_t nlink) | |
577 | { | |
578 | struct proc_dir_entry *ent = NULL; | |
579 | const char *fn = name; | |
580 | int len; | |
581 | ||
582 | /* make sure name is valid */ | |
583 | if (!name || !strlen(name)) goto out; | |
584 | ||
585 | if (!(*parent) && xlate_proc_name(name, parent, &fn) != 0) | |
586 | goto out; | |
587 | ||
588 | /* At this point there must not be any '/' characters beyond *fn */ | |
589 | if (strchr(fn, '/')) | |
590 | goto out; | |
591 | ||
592 | len = strlen(fn); | |
593 | ||
594 | ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL); | |
595 | if (!ent) goto out; | |
596 | ||
597 | memset(ent, 0, sizeof(struct proc_dir_entry)); | |
598 | memcpy(((char *) ent) + sizeof(struct proc_dir_entry), fn, len + 1); | |
599 | ent->name = ((char *) ent) + sizeof(*ent); | |
600 | ent->namelen = len; | |
601 | ent->mode = mode; | |
602 | ent->nlink = nlink; | |
5a622f2d | 603 | atomic_set(&ent->count, 1); |
786d7e16 AD |
604 | ent->pde_users = 0; |
605 | spin_lock_init(&ent->pde_unload_lock); | |
606 | ent->pde_unload_completion = NULL; | |
1da177e4 LT |
607 | out: |
608 | return ent; | |
609 | } | |
610 | ||
611 | struct proc_dir_entry *proc_symlink(const char *name, | |
612 | struct proc_dir_entry *parent, const char *dest) | |
613 | { | |
614 | struct proc_dir_entry *ent; | |
615 | ||
2d3a4e36 | 616 | ent = __proc_create(&parent, name, |
1da177e4 LT |
617 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
618 | ||
619 | if (ent) { | |
620 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
621 | if (ent->data) { | |
622 | strcpy((char*)ent->data,dest); | |
623 | if (proc_register(parent, ent) < 0) { | |
624 | kfree(ent->data); | |
625 | kfree(ent); | |
626 | ent = NULL; | |
627 | } | |
628 | } else { | |
629 | kfree(ent); | |
630 | ent = NULL; | |
631 | } | |
632 | } | |
633 | return ent; | |
634 | } | |
635 | ||
636 | struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode, | |
637 | struct proc_dir_entry *parent) | |
638 | { | |
639 | struct proc_dir_entry *ent; | |
640 | ||
2d3a4e36 | 641 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 642 | if (ent) { |
1da177e4 LT |
643 | if (proc_register(parent, ent) < 0) { |
644 | kfree(ent); | |
645 | ent = NULL; | |
646 | } | |
647 | } | |
648 | return ent; | |
649 | } | |
650 | ||
651 | struct proc_dir_entry *proc_mkdir(const char *name, | |
652 | struct proc_dir_entry *parent) | |
653 | { | |
654 | return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); | |
655 | } | |
656 | ||
657 | struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode, | |
658 | struct proc_dir_entry *parent) | |
659 | { | |
660 | struct proc_dir_entry *ent; | |
661 | nlink_t nlink; | |
662 | ||
663 | if (S_ISDIR(mode)) { | |
664 | if ((mode & S_IALLUGO) == 0) | |
665 | mode |= S_IRUGO | S_IXUGO; | |
666 | nlink = 2; | |
667 | } else { | |
668 | if ((mode & S_IFMT) == 0) | |
669 | mode |= S_IFREG; | |
670 | if ((mode & S_IALLUGO) == 0) | |
671 | mode |= S_IRUGO; | |
672 | nlink = 1; | |
673 | } | |
674 | ||
2d3a4e36 | 675 | ent = __proc_create(&parent, name, mode, nlink); |
1da177e4 | 676 | if (ent) { |
1da177e4 LT |
677 | if (proc_register(parent, ent) < 0) { |
678 | kfree(ent); | |
679 | ent = NULL; | |
680 | } | |
681 | } | |
682 | return ent; | |
683 | } | |
684 | ||
2d3a4e36 AD |
685 | struct proc_dir_entry *proc_create(const char *name, mode_t mode, |
686 | struct proc_dir_entry *parent, | |
687 | const struct file_operations *proc_fops) | |
688 | { | |
689 | struct proc_dir_entry *pde; | |
690 | nlink_t nlink; | |
691 | ||
692 | if (S_ISDIR(mode)) { | |
693 | if ((mode & S_IALLUGO) == 0) | |
694 | mode |= S_IRUGO | S_IXUGO; | |
695 | nlink = 2; | |
696 | } else { | |
697 | if ((mode & S_IFMT) == 0) | |
698 | mode |= S_IFREG; | |
699 | if ((mode & S_IALLUGO) == 0) | |
700 | mode |= S_IRUGO; | |
701 | nlink = 1; | |
702 | } | |
703 | ||
704 | pde = __proc_create(&parent, name, mode, nlink); | |
705 | if (!pde) | |
706 | goto out; | |
707 | pde->proc_fops = proc_fops; | |
708 | if (proc_register(parent, pde) < 0) | |
709 | goto out_free; | |
710 | return pde; | |
711 | out_free: | |
712 | kfree(pde); | |
713 | out: | |
714 | return NULL; | |
715 | } | |
716 | ||
1da177e4 LT |
717 | void free_proc_entry(struct proc_dir_entry *de) |
718 | { | |
719 | unsigned int ino = de->low_ino; | |
720 | ||
721 | if (ino < PROC_DYNAMIC_FIRST) | |
722 | return; | |
723 | ||
724 | release_inode_number(ino); | |
725 | ||
fd2cbe48 | 726 | if (S_ISLNK(de->mode)) |
1da177e4 LT |
727 | kfree(de->data); |
728 | kfree(de); | |
729 | } | |
730 | ||
731 | /* | |
732 | * Remove a /proc entry and free it if it's not currently in use. | |
1da177e4 LT |
733 | */ |
734 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
735 | { | |
736 | struct proc_dir_entry **p; | |
737 | struct proc_dir_entry *de; | |
738 | const char *fn = name; | |
739 | int len; | |
740 | ||
741 | if (!parent && xlate_proc_name(name, &parent, &fn) != 0) | |
742 | goto out; | |
743 | len = strlen(fn); | |
64a07bd8 SR |
744 | |
745 | spin_lock(&proc_subdir_lock); | |
1da177e4 LT |
746 | for (p = &parent->subdir; *p; p=&(*p)->next ) { |
747 | if (!proc_match(len, fn, *p)) | |
748 | continue; | |
749 | de = *p; | |
750 | *p = de->next; | |
751 | de->next = NULL; | |
786d7e16 AD |
752 | |
753 | spin_lock(&de->pde_unload_lock); | |
754 | /* | |
755 | * Stop accepting new callers into module. If you're | |
756 | * dynamically allocating ->proc_fops, save a pointer somewhere. | |
757 | */ | |
758 | de->proc_fops = NULL; | |
759 | /* Wait until all existing callers into module are done. */ | |
760 | if (de->pde_users > 0) { | |
761 | DECLARE_COMPLETION_ONSTACK(c); | |
762 | ||
763 | if (!de->pde_unload_completion) | |
764 | de->pde_unload_completion = &c; | |
765 | ||
766 | spin_unlock(&de->pde_unload_lock); | |
767 | spin_unlock(&proc_subdir_lock); | |
768 | ||
769 | wait_for_completion(de->pde_unload_completion); | |
770 | ||
771 | spin_lock(&proc_subdir_lock); | |
772 | goto continue_removing; | |
773 | } | |
774 | spin_unlock(&de->pde_unload_lock); | |
775 | ||
776 | continue_removing: | |
1da177e4 LT |
777 | if (S_ISDIR(de->mode)) |
778 | parent->nlink--; | |
1da177e4 | 779 | de->nlink = 0; |
e93b4ea2 AD |
780 | if (de->subdir) { |
781 | printk(KERN_WARNING "%s: removing non-empty directory " | |
782 | "'%s/%s', leaking at least '%s'\n", __func__, | |
783 | de->parent->name, de->name, de->subdir->name); | |
784 | WARN_ON(1); | |
785 | } | |
5a622f2d | 786 | if (atomic_dec_and_test(&de->count)) |
1da177e4 | 787 | free_proc_entry(de); |
1da177e4 LT |
788 | break; |
789 | } | |
64a07bd8 | 790 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
791 | out: |
792 | return; | |
793 | } |