Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * proc/fs/generic.c --- generic routines for the proc-fs | |
3 | * | |
4 | * This file contains generic proc-fs routines for handling | |
5 | * directories and files. | |
6 | * | |
7 | * Copyright (C) 1991, 1992 Linus Torvalds. | |
8 | * Copyright (C) 1997 Theodore Ts'o | |
9 | */ | |
10 | ||
11 | #include <linux/errno.h> | |
12 | #include <linux/time.h> | |
13 | #include <linux/proc_fs.h> | |
14 | #include <linux/stat.h> | |
1025774c | 15 | #include <linux/mm.h> |
1da177e4 | 16 | #include <linux/module.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
1da177e4 | 18 | #include <linux/mount.h> |
1da177e4 LT |
19 | #include <linux/init.h> |
20 | #include <linux/idr.h> | |
21 | #include <linux/namei.h> | |
22 | #include <linux/bitops.h> | |
64a07bd8 | 23 | #include <linux/spinlock.h> |
786d7e16 | 24 | #include <linux/completion.h> |
1da177e4 LT |
25 | #include <asm/uaccess.h> |
26 | ||
fee781e6 AB |
27 | #include "internal.h" |
28 | ||
64a07bd8 SR |
29 | DEFINE_SPINLOCK(proc_subdir_lock); |
30 | ||
312ec7e5 | 31 | static int proc_match(unsigned int len, const char *name, struct proc_dir_entry *de) |
1da177e4 LT |
32 | { |
33 | if (de->namelen != len) | |
34 | return 0; | |
35 | return !memcmp(name, de->name, len); | |
36 | } | |
37 | ||
1da177e4 LT |
38 | /* buffer size is one page but our output routines use some slack for overruns */ |
39 | #define PROC_BLOCK_SIZE (PAGE_SIZE - 1024) | |
40 | ||
41 | static ssize_t | |
3dec7f59 | 42 | __proc_file_read(struct file *file, char __user *buf, size_t nbytes, |
1da177e4 LT |
43 | loff_t *ppos) |
44 | { | |
2fddfeef | 45 | struct inode * inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
46 | char *page; |
47 | ssize_t retval=0; | |
48 | int eof=0; | |
49 | ssize_t n, count; | |
50 | char *start; | |
51 | struct proc_dir_entry * dp; | |
8b90db0d LT |
52 | unsigned long long pos; |
53 | ||
54 | /* | |
55 | * Gaah, please just use "seq_file" instead. The legacy /proc | |
56 | * interfaces cut loff_t down to off_t for reads, and ignore | |
57 | * the offset entirely for writes.. | |
58 | */ | |
59 | pos = *ppos; | |
60 | if (pos > MAX_NON_LFS) | |
61 | return 0; | |
62 | if (nbytes > MAX_NON_LFS - pos) | |
63 | nbytes = MAX_NON_LFS - pos; | |
1da177e4 LT |
64 | |
65 | dp = PDE(inode); | |
e12ba74d | 66 | if (!(page = (char*) __get_free_page(GFP_TEMPORARY))) |
1da177e4 LT |
67 | return -ENOMEM; |
68 | ||
69 | while ((nbytes > 0) && !eof) { | |
70 | count = min_t(size_t, PROC_BLOCK_SIZE, nbytes); | |
71 | ||
72 | start = NULL; | |
8731f14d | 73 | if (dp->read_proc) { |
1da177e4 LT |
74 | /* |
75 | * How to be a proc read function | |
76 | * ------------------------------ | |
77 | * Prototype: | |
78 | * int f(char *buffer, char **start, off_t offset, | |
79 | * int count, int *peof, void *dat) | |
80 | * | |
81 | * Assume that the buffer is "count" bytes in size. | |
82 | * | |
83 | * If you know you have supplied all the data you | |
84 | * have, set *peof. | |
85 | * | |
86 | * You have three ways to return data: | |
87 | * 0) Leave *start = NULL. (This is the default.) | |
88 | * Put the data of the requested offset at that | |
89 | * offset within the buffer. Return the number (n) | |
90 | * of bytes there are from the beginning of the | |
91 | * buffer up to the last byte of data. If the | |
92 | * number of supplied bytes (= n - offset) is | |
93 | * greater than zero and you didn't signal eof | |
94 | * and the reader is prepared to take more data | |
95 | * you will be called again with the requested | |
96 | * offset advanced by the number of bytes | |
97 | * absorbed. This interface is useful for files | |
98 | * no larger than the buffer. | |
99 | * 1) Set *start = an unsigned long value less than | |
100 | * the buffer address but greater than zero. | |
101 | * Put the data of the requested offset at the | |
102 | * beginning of the buffer. Return the number of | |
103 | * bytes of data placed there. If this number is | |
104 | * greater than zero and you didn't signal eof | |
105 | * and the reader is prepared to take more data | |
106 | * you will be called again with the requested | |
107 | * offset advanced by *start. This interface is | |
108 | * useful when you have a large file consisting | |
109 | * of a series of blocks which you want to count | |
110 | * and return as wholes. | |
111 | * (Hack by Paul.Russell@rustcorp.com.au) | |
112 | * 2) Set *start = an address within the buffer. | |
113 | * Put the data of the requested offset at *start. | |
114 | * Return the number of bytes of data placed there. | |
115 | * If this number is greater than zero and you | |
116 | * didn't signal eof and the reader is prepared to | |
117 | * take more data you will be called again with the | |
118 | * requested offset advanced by the number of bytes | |
119 | * absorbed. | |
120 | */ | |
121 | n = dp->read_proc(page, &start, *ppos, | |
122 | count, &eof, dp->data); | |
123 | } else | |
124 | break; | |
125 | ||
126 | if (n == 0) /* end of file */ | |
127 | break; | |
128 | if (n < 0) { /* error */ | |
129 | if (retval == 0) | |
130 | retval = n; | |
131 | break; | |
132 | } | |
133 | ||
134 | if (start == NULL) { | |
135 | if (n > PAGE_SIZE) { | |
136 | printk(KERN_ERR | |
137 | "proc_file_read: Apparent buffer overflow!\n"); | |
138 | n = PAGE_SIZE; | |
139 | } | |
140 | n -= *ppos; | |
141 | if (n <= 0) | |
142 | break; | |
143 | if (n > count) | |
144 | n = count; | |
145 | start = page + *ppos; | |
146 | } else if (start < page) { | |
147 | if (n > PAGE_SIZE) { | |
148 | printk(KERN_ERR | |
149 | "proc_file_read: Apparent buffer overflow!\n"); | |
150 | n = PAGE_SIZE; | |
151 | } | |
152 | if (n > count) { | |
153 | /* | |
154 | * Don't reduce n because doing so might | |
155 | * cut off part of a data block. | |
156 | */ | |
157 | printk(KERN_WARNING | |
158 | "proc_file_read: Read count exceeded\n"); | |
159 | } | |
160 | } else /* start >= page */ { | |
161 | unsigned long startoff = (unsigned long)(start - page); | |
162 | if (n > (PAGE_SIZE - startoff)) { | |
163 | printk(KERN_ERR | |
164 | "proc_file_read: Apparent buffer overflow!\n"); | |
165 | n = PAGE_SIZE - startoff; | |
166 | } | |
167 | if (n > count) | |
168 | n = count; | |
169 | } | |
170 | ||
171 | n -= copy_to_user(buf, start < page ? page : start, n); | |
172 | if (n == 0) { | |
173 | if (retval == 0) | |
174 | retval = -EFAULT; | |
175 | break; | |
176 | } | |
177 | ||
178 | *ppos += start < page ? (unsigned long)start : n; | |
179 | nbytes -= n; | |
180 | buf += n; | |
181 | retval += n; | |
182 | } | |
183 | free_page((unsigned long) page); | |
184 | return retval; | |
185 | } | |
186 | ||
3dec7f59 AD |
187 | static ssize_t |
188 | proc_file_read(struct file *file, char __user *buf, size_t nbytes, | |
189 | loff_t *ppos) | |
190 | { | |
191 | struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); | |
192 | ssize_t rv = -EIO; | |
193 | ||
194 | spin_lock(&pde->pde_unload_lock); | |
195 | if (!pde->proc_fops) { | |
196 | spin_unlock(&pde->pde_unload_lock); | |
197 | return rv; | |
198 | } | |
199 | pde->pde_users++; | |
200 | spin_unlock(&pde->pde_unload_lock); | |
201 | ||
202 | rv = __proc_file_read(file, buf, nbytes, ppos); | |
203 | ||
204 | pde_users_dec(pde); | |
205 | return rv; | |
206 | } | |
207 | ||
1da177e4 LT |
208 | static ssize_t |
209 | proc_file_write(struct file *file, const char __user *buffer, | |
210 | size_t count, loff_t *ppos) | |
211 | { | |
3dec7f59 AD |
212 | struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); |
213 | ssize_t rv = -EIO; | |
214 | ||
215 | if (pde->write_proc) { | |
216 | spin_lock(&pde->pde_unload_lock); | |
217 | if (!pde->proc_fops) { | |
218 | spin_unlock(&pde->pde_unload_lock); | |
219 | return rv; | |
220 | } | |
221 | pde->pde_users++; | |
222 | spin_unlock(&pde->pde_unload_lock); | |
1da177e4 | 223 | |
3dec7f59 AD |
224 | /* FIXME: does this routine need ppos? probably... */ |
225 | rv = pde->write_proc(file, buffer, count, pde->data); | |
226 | pde_users_dec(pde); | |
227 | } | |
228 | return rv; | |
1da177e4 LT |
229 | } |
230 | ||
231 | ||
232 | static loff_t | |
233 | proc_file_lseek(struct file *file, loff_t offset, int orig) | |
234 | { | |
8b90db0d LT |
235 | loff_t retval = -EINVAL; |
236 | switch (orig) { | |
237 | case 1: | |
238 | offset += file->f_pos; | |
239 | /* fallthrough */ | |
240 | case 0: | |
241 | if (offset < 0 || offset > MAX_NON_LFS) | |
242 | break; | |
243 | file->f_pos = retval = offset; | |
244 | } | |
245 | return retval; | |
1da177e4 LT |
246 | } |
247 | ||
76df0c25 AD |
248 | static const struct file_operations proc_file_operations = { |
249 | .llseek = proc_file_lseek, | |
250 | .read = proc_file_read, | |
251 | .write = proc_file_write, | |
252 | }; | |
253 | ||
1da177e4 LT |
254 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) |
255 | { | |
256 | struct inode *inode = dentry->d_inode; | |
257 | struct proc_dir_entry *de = PDE(inode); | |
258 | int error; | |
259 | ||
260 | error = inode_change_ok(inode, iattr); | |
261 | if (error) | |
1025774c | 262 | return error; |
1da177e4 | 263 | |
1025774c CH |
264 | if ((iattr->ia_valid & ATTR_SIZE) && |
265 | iattr->ia_size != i_size_read(inode)) { | |
266 | error = vmtruncate(inode, iattr->ia_size); | |
267 | if (error) | |
268 | return error; | |
269 | } | |
270 | ||
271 | setattr_copy(inode, iattr); | |
272 | mark_inode_dirty(inode); | |
1da177e4 LT |
273 | |
274 | de->uid = inode->i_uid; | |
275 | de->gid = inode->i_gid; | |
276 | de->mode = inode->i_mode; | |
1025774c | 277 | return 0; |
1da177e4 LT |
278 | } |
279 | ||
2b579bee MS |
280 | static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry, |
281 | struct kstat *stat) | |
282 | { | |
283 | struct inode *inode = dentry->d_inode; | |
284 | struct proc_dir_entry *de = PROC_I(inode)->pde; | |
285 | if (de && de->nlink) | |
bfe86848 | 286 | set_nlink(inode, de->nlink); |
2b579bee MS |
287 | |
288 | generic_fillattr(inode, stat); | |
289 | return 0; | |
290 | } | |
291 | ||
c5ef1c42 | 292 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
293 | .setattr = proc_notify_change, |
294 | }; | |
295 | ||
296 | /* | |
297 | * This function parses a name such as "tty/driver/serial", and | |
298 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
299 | * returns "serial" in residual. | |
300 | */ | |
e17a5765 AD |
301 | static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret, |
302 | const char **residual) | |
1da177e4 LT |
303 | { |
304 | const char *cp = name, *next; | |
305 | struct proc_dir_entry *de; | |
312ec7e5 | 306 | unsigned int len; |
1da177e4 | 307 | |
7cee4e00 AD |
308 | de = *ret; |
309 | if (!de) | |
310 | de = &proc_root; | |
311 | ||
1da177e4 LT |
312 | while (1) { |
313 | next = strchr(cp, '/'); | |
314 | if (!next) | |
315 | break; | |
316 | ||
317 | len = next - cp; | |
318 | for (de = de->subdir; de ; de = de->next) { | |
319 | if (proc_match(len, cp, de)) | |
320 | break; | |
321 | } | |
12bac0d9 AD |
322 | if (!de) { |
323 | WARN(1, "name '%s'\n", name); | |
e17a5765 | 324 | return -ENOENT; |
12bac0d9 | 325 | } |
1da177e4 LT |
326 | cp += len + 1; |
327 | } | |
328 | *residual = cp; | |
329 | *ret = de; | |
e17a5765 AD |
330 | return 0; |
331 | } | |
332 | ||
333 | static int xlate_proc_name(const char *name, struct proc_dir_entry **ret, | |
334 | const char **residual) | |
335 | { | |
336 | int rv; | |
337 | ||
338 | spin_lock(&proc_subdir_lock); | |
339 | rv = __xlate_proc_name(name, ret, residual); | |
64a07bd8 | 340 | spin_unlock(&proc_subdir_lock); |
e17a5765 | 341 | return rv; |
1da177e4 LT |
342 | } |
343 | ||
9a185409 | 344 | static DEFINE_IDA(proc_inum_ida); |
1da177e4 LT |
345 | static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ |
346 | ||
67935df4 | 347 | #define PROC_DYNAMIC_FIRST 0xF0000000U |
1da177e4 LT |
348 | |
349 | /* | |
350 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
351 | * 0xffffffff, or zero on failure. | |
352 | */ | |
353 | static unsigned int get_inode_number(void) | |
354 | { | |
67935df4 | 355 | unsigned int i; |
1da177e4 LT |
356 | int error; |
357 | ||
358 | retry: | |
9a185409 | 359 | if (ida_pre_get(&proc_inum_ida, GFP_KERNEL) == 0) |
1da177e4 LT |
360 | return 0; |
361 | ||
362 | spin_lock(&proc_inum_lock); | |
9a185409 | 363 | error = ida_get_new(&proc_inum_ida, &i); |
1da177e4 LT |
364 | spin_unlock(&proc_inum_lock); |
365 | if (error == -EAGAIN) | |
366 | goto retry; | |
367 | else if (error) | |
368 | return 0; | |
369 | ||
67935df4 AD |
370 | if (i > UINT_MAX - PROC_DYNAMIC_FIRST) { |
371 | spin_lock(&proc_inum_lock); | |
9a185409 | 372 | ida_remove(&proc_inum_ida, i); |
67935df4 | 373 | spin_unlock(&proc_inum_lock); |
cc996099 | 374 | return 0; |
67935df4 AD |
375 | } |
376 | return PROC_DYNAMIC_FIRST + i; | |
1da177e4 LT |
377 | } |
378 | ||
379 | static void release_inode_number(unsigned int inum) | |
380 | { | |
1da177e4 | 381 | spin_lock(&proc_inum_lock); |
9a185409 | 382 | ida_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); |
1da177e4 LT |
383 | spin_unlock(&proc_inum_lock); |
384 | } | |
385 | ||
008b150a | 386 | static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
387 | { |
388 | nd_set_link(nd, PDE(dentry->d_inode)->data); | |
008b150a | 389 | return NULL; |
1da177e4 LT |
390 | } |
391 | ||
c5ef1c42 | 392 | static const struct inode_operations proc_link_inode_operations = { |
1da177e4 LT |
393 | .readlink = generic_readlink, |
394 | .follow_link = proc_follow_link, | |
395 | }; | |
396 | ||
397 | /* | |
398 | * As some entries in /proc are volatile, we want to | |
399 | * get rid of unused dentries. This could be made | |
400 | * smarter: we could keep a "volatile" flag in the | |
401 | * inode to indicate which ones to keep. | |
402 | */ | |
fe15ce44 | 403 | static int proc_delete_dentry(const struct dentry * dentry) |
1da177e4 LT |
404 | { |
405 | return 1; | |
406 | } | |
407 | ||
d72f71eb | 408 | static const struct dentry_operations proc_dentry_operations = |
1da177e4 LT |
409 | { |
410 | .d_delete = proc_delete_dentry, | |
411 | }; | |
412 | ||
413 | /* | |
414 | * Don't create negative dentries here, return -ENOENT by hand | |
415 | * instead. | |
416 | */ | |
e9720acd PE |
417 | struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir, |
418 | struct dentry *dentry) | |
1da177e4 LT |
419 | { |
420 | struct inode *inode = NULL; | |
1da177e4 LT |
421 | int error = -ENOENT; |
422 | ||
64a07bd8 | 423 | spin_lock(&proc_subdir_lock); |
5e971dce AD |
424 | for (de = de->subdir; de ; de = de->next) { |
425 | if (de->namelen != dentry->d_name.len) | |
426 | continue; | |
427 | if (!memcmp(dentry->d_name.name, de->name, de->namelen)) { | |
135d5655 | 428 | pde_get(de); |
5e971dce AD |
429 | spin_unlock(&proc_subdir_lock); |
430 | error = -EINVAL; | |
6d1b6e4e | 431 | inode = proc_get_inode(dir->i_sb, de); |
5e971dce | 432 | goto out_unlock; |
1da177e4 LT |
433 | } |
434 | } | |
64a07bd8 | 435 | spin_unlock(&proc_subdir_lock); |
4237e0d3 | 436 | out_unlock: |
1da177e4 LT |
437 | |
438 | if (inode) { | |
fb045adb | 439 | d_set_d_op(dentry, &proc_dentry_operations); |
1da177e4 LT |
440 | d_add(dentry, inode); |
441 | return NULL; | |
442 | } | |
5e971dce | 443 | if (de) |
135d5655 | 444 | pde_put(de); |
1da177e4 LT |
445 | return ERR_PTR(error); |
446 | } | |
447 | ||
e9720acd PE |
448 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
449 | struct nameidata *nd) | |
450 | { | |
451 | return proc_lookup_de(PDE(dir), dir, dentry); | |
452 | } | |
453 | ||
1da177e4 LT |
454 | /* |
455 | * This returns non-zero if at EOF, so that the /proc | |
456 | * root directory can use this and check if it should | |
457 | * continue with the <pid> entries.. | |
458 | * | |
459 | * Note that the VFS-layer doesn't care about the return | |
460 | * value of the readdir() call, as long as it's non-negative | |
461 | * for success.. | |
462 | */ | |
e9720acd PE |
463 | int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent, |
464 | filldir_t filldir) | |
1da177e4 | 465 | { |
1da177e4 LT |
466 | unsigned int ino; |
467 | int i; | |
2fddfeef | 468 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
469 | int ret = 0; |
470 | ||
1da177e4 | 471 | ino = inode->i_ino; |
1da177e4 LT |
472 | i = filp->f_pos; |
473 | switch (i) { | |
474 | case 0: | |
475 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
476 | goto out; | |
477 | i++; | |
478 | filp->f_pos++; | |
479 | /* fall through */ | |
480 | case 1: | |
481 | if (filldir(dirent, "..", 2, i, | |
2fddfeef | 482 | parent_ino(filp->f_path.dentry), |
1da177e4 LT |
483 | DT_DIR) < 0) |
484 | goto out; | |
485 | i++; | |
486 | filp->f_pos++; | |
487 | /* fall through */ | |
488 | default: | |
64a07bd8 | 489 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
490 | de = de->subdir; |
491 | i -= 2; | |
492 | for (;;) { | |
493 | if (!de) { | |
494 | ret = 1; | |
64a07bd8 | 495 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
496 | goto out; |
497 | } | |
498 | if (!i) | |
499 | break; | |
500 | de = de->next; | |
501 | i--; | |
502 | } | |
503 | ||
504 | do { | |
59cd0cbc DW |
505 | struct proc_dir_entry *next; |
506 | ||
64a07bd8 | 507 | /* filldir passes info to user space */ |
135d5655 | 508 | pde_get(de); |
64a07bd8 | 509 | spin_unlock(&proc_subdir_lock); |
1da177e4 | 510 | if (filldir(dirent, de->name, de->namelen, filp->f_pos, |
59cd0cbc | 511 | de->low_ino, de->mode >> 12) < 0) { |
135d5655 | 512 | pde_put(de); |
1da177e4 | 513 | goto out; |
59cd0cbc | 514 | } |
64a07bd8 | 515 | spin_lock(&proc_subdir_lock); |
1da177e4 | 516 | filp->f_pos++; |
59cd0cbc | 517 | next = de->next; |
135d5655 | 518 | pde_put(de); |
59cd0cbc | 519 | de = next; |
1da177e4 | 520 | } while (de); |
64a07bd8 | 521 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
522 | } |
523 | ret = 1; | |
b4df2b92 | 524 | out: |
1da177e4 LT |
525 | return ret; |
526 | } | |
527 | ||
e9720acd PE |
528 | int proc_readdir(struct file *filp, void *dirent, filldir_t filldir) |
529 | { | |
530 | struct inode *inode = filp->f_path.dentry->d_inode; | |
531 | ||
532 | return proc_readdir_de(PDE(inode), filp, dirent, filldir); | |
533 | } | |
534 | ||
1da177e4 LT |
535 | /* |
536 | * These are the generic /proc directory operations. They | |
537 | * use the in-memory "struct proc_dir_entry" tree to parse | |
538 | * the /proc directory. | |
539 | */ | |
00977a59 | 540 | static const struct file_operations proc_dir_operations = { |
b4df2b92 | 541 | .llseek = generic_file_llseek, |
1da177e4 LT |
542 | .read = generic_read_dir, |
543 | .readdir = proc_readdir, | |
544 | }; | |
545 | ||
546 | /* | |
547 | * proc directories can do almost nothing.. | |
548 | */ | |
c5ef1c42 | 549 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 550 | .lookup = proc_lookup, |
2b579bee | 551 | .getattr = proc_getattr, |
1da177e4 LT |
552 | .setattr = proc_notify_change, |
553 | }; | |
554 | ||
555 | static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) | |
556 | { | |
557 | unsigned int i; | |
94413d88 | 558 | struct proc_dir_entry *tmp; |
1da177e4 LT |
559 | |
560 | i = get_inode_number(); | |
561 | if (i == 0) | |
562 | return -EAGAIN; | |
563 | dp->low_ino = i; | |
64a07bd8 | 564 | |
1da177e4 LT |
565 | if (S_ISDIR(dp->mode)) { |
566 | if (dp->proc_iops == NULL) { | |
567 | dp->proc_fops = &proc_dir_operations; | |
568 | dp->proc_iops = &proc_dir_inode_operations; | |
569 | } | |
570 | dir->nlink++; | |
571 | } else if (S_ISLNK(dp->mode)) { | |
572 | if (dp->proc_iops == NULL) | |
573 | dp->proc_iops = &proc_link_inode_operations; | |
574 | } else if (S_ISREG(dp->mode)) { | |
575 | if (dp->proc_fops == NULL) | |
576 | dp->proc_fops = &proc_file_operations; | |
577 | if (dp->proc_iops == NULL) | |
578 | dp->proc_iops = &proc_file_inode_operations; | |
579 | } | |
99fc06df CG |
580 | |
581 | spin_lock(&proc_subdir_lock); | |
94413d88 ZR |
582 | |
583 | for (tmp = dir->subdir; tmp; tmp = tmp->next) | |
584 | if (strcmp(tmp->name, dp->name) == 0) { | |
6c2f91e0 | 585 | WARN(1, KERN_WARNING "proc_dir_entry '%s/%s' already registered\n", |
665020c3 | 586 | dir->name, dp->name); |
94413d88 ZR |
587 | break; |
588 | } | |
589 | ||
99fc06df CG |
590 | dp->next = dir->subdir; |
591 | dp->parent = dir; | |
592 | dir->subdir = dp; | |
593 | spin_unlock(&proc_subdir_lock); | |
594 | ||
1da177e4 LT |
595 | return 0; |
596 | } | |
597 | ||
2d3a4e36 | 598 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 | 599 | const char *name, |
d161a13f | 600 | umode_t mode, |
1da177e4 LT |
601 | nlink_t nlink) |
602 | { | |
603 | struct proc_dir_entry *ent = NULL; | |
604 | const char *fn = name; | |
312ec7e5 | 605 | unsigned int len; |
1da177e4 LT |
606 | |
607 | /* make sure name is valid */ | |
608 | if (!name || !strlen(name)) goto out; | |
609 | ||
7cee4e00 | 610 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 LT |
611 | goto out; |
612 | ||
613 | /* At this point there must not be any '/' characters beyond *fn */ | |
614 | if (strchr(fn, '/')) | |
615 | goto out; | |
616 | ||
617 | len = strlen(fn); | |
618 | ||
619 | ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL); | |
620 | if (!ent) goto out; | |
621 | ||
622 | memset(ent, 0, sizeof(struct proc_dir_entry)); | |
09570f91 | 623 | memcpy(ent->name, fn, len + 1); |
1da177e4 LT |
624 | ent->namelen = len; |
625 | ent->mode = mode; | |
626 | ent->nlink = nlink; | |
5a622f2d | 627 | atomic_set(&ent->count, 1); |
786d7e16 AD |
628 | ent->pde_users = 0; |
629 | spin_lock_init(&ent->pde_unload_lock); | |
630 | ent->pde_unload_completion = NULL; | |
881adb85 | 631 | INIT_LIST_HEAD(&ent->pde_openers); |
1da177e4 LT |
632 | out: |
633 | return ent; | |
634 | } | |
635 | ||
636 | struct proc_dir_entry *proc_symlink(const char *name, | |
637 | struct proc_dir_entry *parent, const char *dest) | |
638 | { | |
639 | struct proc_dir_entry *ent; | |
640 | ||
2d3a4e36 | 641 | ent = __proc_create(&parent, name, |
1da177e4 LT |
642 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
643 | ||
644 | if (ent) { | |
645 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
646 | if (ent->data) { | |
647 | strcpy((char*)ent->data,dest); | |
648 | if (proc_register(parent, ent) < 0) { | |
649 | kfree(ent->data); | |
650 | kfree(ent); | |
651 | ent = NULL; | |
652 | } | |
653 | } else { | |
654 | kfree(ent); | |
655 | ent = NULL; | |
656 | } | |
657 | } | |
658 | return ent; | |
659 | } | |
587d4a17 | 660 | EXPORT_SYMBOL(proc_symlink); |
1da177e4 | 661 | |
d161a13f | 662 | struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode, |
1da177e4 LT |
663 | struct proc_dir_entry *parent) |
664 | { | |
665 | struct proc_dir_entry *ent; | |
666 | ||
2d3a4e36 | 667 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 668 | if (ent) { |
1da177e4 LT |
669 | if (proc_register(parent, ent) < 0) { |
670 | kfree(ent); | |
671 | ent = NULL; | |
672 | } | |
673 | } | |
674 | return ent; | |
675 | } | |
011159a0 | 676 | EXPORT_SYMBOL(proc_mkdir_mode); |
1da177e4 | 677 | |
78e92b99 DL |
678 | struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name, |
679 | struct proc_dir_entry *parent) | |
680 | { | |
681 | struct proc_dir_entry *ent; | |
682 | ||
683 | ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2); | |
684 | if (ent) { | |
685 | ent->data = net; | |
686 | if (proc_register(parent, ent) < 0) { | |
687 | kfree(ent); | |
688 | ent = NULL; | |
689 | } | |
690 | } | |
691 | return ent; | |
692 | } | |
693 | EXPORT_SYMBOL_GPL(proc_net_mkdir); | |
694 | ||
1da177e4 LT |
695 | struct proc_dir_entry *proc_mkdir(const char *name, |
696 | struct proc_dir_entry *parent) | |
697 | { | |
698 | return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); | |
699 | } | |
587d4a17 | 700 | EXPORT_SYMBOL(proc_mkdir); |
1da177e4 | 701 | |
d161a13f | 702 | struct proc_dir_entry *create_proc_entry(const char *name, umode_t mode, |
1da177e4 LT |
703 | struct proc_dir_entry *parent) |
704 | { | |
705 | struct proc_dir_entry *ent; | |
706 | nlink_t nlink; | |
707 | ||
708 | if (S_ISDIR(mode)) { | |
709 | if ((mode & S_IALLUGO) == 0) | |
710 | mode |= S_IRUGO | S_IXUGO; | |
711 | nlink = 2; | |
712 | } else { | |
713 | if ((mode & S_IFMT) == 0) | |
714 | mode |= S_IFREG; | |
715 | if ((mode & S_IALLUGO) == 0) | |
716 | mode |= S_IRUGO; | |
717 | nlink = 1; | |
718 | } | |
719 | ||
2d3a4e36 | 720 | ent = __proc_create(&parent, name, mode, nlink); |
1da177e4 | 721 | if (ent) { |
1da177e4 LT |
722 | if (proc_register(parent, ent) < 0) { |
723 | kfree(ent); | |
724 | ent = NULL; | |
725 | } | |
726 | } | |
727 | return ent; | |
728 | } | |
587d4a17 | 729 | EXPORT_SYMBOL(create_proc_entry); |
1da177e4 | 730 | |
d161a13f | 731 | struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, |
59b74351 DL |
732 | struct proc_dir_entry *parent, |
733 | const struct file_operations *proc_fops, | |
734 | void *data) | |
2d3a4e36 AD |
735 | { |
736 | struct proc_dir_entry *pde; | |
737 | nlink_t nlink; | |
738 | ||
739 | if (S_ISDIR(mode)) { | |
740 | if ((mode & S_IALLUGO) == 0) | |
741 | mode |= S_IRUGO | S_IXUGO; | |
742 | nlink = 2; | |
743 | } else { | |
744 | if ((mode & S_IFMT) == 0) | |
745 | mode |= S_IFREG; | |
746 | if ((mode & S_IALLUGO) == 0) | |
747 | mode |= S_IRUGO; | |
748 | nlink = 1; | |
749 | } | |
750 | ||
751 | pde = __proc_create(&parent, name, mode, nlink); | |
752 | if (!pde) | |
753 | goto out; | |
754 | pde->proc_fops = proc_fops; | |
59b74351 | 755 | pde->data = data; |
2d3a4e36 AD |
756 | if (proc_register(parent, pde) < 0) |
757 | goto out_free; | |
758 | return pde; | |
759 | out_free: | |
760 | kfree(pde); | |
761 | out: | |
762 | return NULL; | |
763 | } | |
587d4a17 | 764 | EXPORT_SYMBOL(proc_create_data); |
2d3a4e36 | 765 | |
135d5655 | 766 | static void free_proc_entry(struct proc_dir_entry *de) |
1da177e4 | 767 | { |
6d1b6e4e | 768 | release_inode_number(de->low_ino); |
1da177e4 | 769 | |
fd2cbe48 | 770 | if (S_ISLNK(de->mode)) |
1da177e4 LT |
771 | kfree(de->data); |
772 | kfree(de); | |
773 | } | |
774 | ||
135d5655 AD |
775 | void pde_put(struct proc_dir_entry *pde) |
776 | { | |
777 | if (atomic_dec_and_test(&pde->count)) | |
778 | free_proc_entry(pde); | |
779 | } | |
780 | ||
1da177e4 LT |
781 | /* |
782 | * Remove a /proc entry and free it if it's not currently in use. | |
1da177e4 LT |
783 | */ |
784 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
785 | { | |
786 | struct proc_dir_entry **p; | |
f649d6d3 | 787 | struct proc_dir_entry *de = NULL; |
1da177e4 | 788 | const char *fn = name; |
312ec7e5 | 789 | unsigned int len; |
1da177e4 | 790 | |
e17a5765 AD |
791 | spin_lock(&proc_subdir_lock); |
792 | if (__xlate_proc_name(name, &parent, &fn) != 0) { | |
793 | spin_unlock(&proc_subdir_lock); | |
f649d6d3 | 794 | return; |
e17a5765 | 795 | } |
1da177e4 | 796 | len = strlen(fn); |
64a07bd8 | 797 | |
1da177e4 | 798 | for (p = &parent->subdir; *p; p=&(*p)->next ) { |
f649d6d3 AD |
799 | if (proc_match(len, fn, *p)) { |
800 | de = *p; | |
801 | *p = de->next; | |
802 | de->next = NULL; | |
803 | break; | |
804 | } | |
805 | } | |
806 | spin_unlock(&proc_subdir_lock); | |
12bac0d9 AD |
807 | if (!de) { |
808 | WARN(1, "name '%s'\n", name); | |
f649d6d3 | 809 | return; |
12bac0d9 | 810 | } |
786d7e16 | 811 | |
f649d6d3 AD |
812 | spin_lock(&de->pde_unload_lock); |
813 | /* | |
814 | * Stop accepting new callers into module. If you're | |
815 | * dynamically allocating ->proc_fops, save a pointer somewhere. | |
816 | */ | |
817 | de->proc_fops = NULL; | |
818 | /* Wait until all existing callers into module are done. */ | |
819 | if (de->pde_users > 0) { | |
820 | DECLARE_COMPLETION_ONSTACK(c); | |
821 | ||
822 | if (!de->pde_unload_completion) | |
823 | de->pde_unload_completion = &c; | |
786d7e16 | 824 | |
786d7e16 AD |
825 | spin_unlock(&de->pde_unload_lock); |
826 | ||
f649d6d3 AD |
827 | wait_for_completion(de->pde_unload_completion); |
828 | ||
3740a20c | 829 | spin_lock(&de->pde_unload_lock); |
f649d6d3 | 830 | } |
f649d6d3 | 831 | |
881adb85 AD |
832 | while (!list_empty(&de->pde_openers)) { |
833 | struct pde_opener *pdeo; | |
834 | ||
835 | pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh); | |
836 | list_del(&pdeo->lh); | |
837 | spin_unlock(&de->pde_unload_lock); | |
838 | pdeo->release(pdeo->inode, pdeo->file); | |
839 | kfree(pdeo); | |
840 | spin_lock(&de->pde_unload_lock); | |
841 | } | |
842 | spin_unlock(&de->pde_unload_lock); | |
843 | ||
f649d6d3 AD |
844 | if (S_ISDIR(de->mode)) |
845 | parent->nlink--; | |
846 | de->nlink = 0; | |
267e2a9c | 847 | WARN(de->subdir, KERN_WARNING "%s: removing non-empty directory " |
f649d6d3 AD |
848 | "'%s/%s', leaking at least '%s'\n", __func__, |
849 | de->parent->name, de->name, de->subdir->name); | |
135d5655 | 850 | pde_put(de); |
1da177e4 | 851 | } |
587d4a17 | 852 | EXPORT_SYMBOL(remove_proc_entry); |