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> |
87ebdc00 | 18 | #include <linux/printk.h> |
1da177e4 | 19 | #include <linux/mount.h> |
1da177e4 LT |
20 | #include <linux/init.h> |
21 | #include <linux/idr.h> | |
22 | #include <linux/namei.h> | |
23 | #include <linux/bitops.h> | |
64a07bd8 | 24 | #include <linux/spinlock.h> |
786d7e16 | 25 | #include <linux/completion.h> |
1da177e4 LT |
26 | #include <asm/uaccess.h> |
27 | ||
fee781e6 AB |
28 | #include "internal.h" |
29 | ||
64a07bd8 SR |
30 | DEFINE_SPINLOCK(proc_subdir_lock); |
31 | ||
312ec7e5 | 32 | static int proc_match(unsigned int len, const char *name, struct proc_dir_entry *de) |
1da177e4 LT |
33 | { |
34 | if (de->namelen != len) | |
35 | return 0; | |
36 | return !memcmp(name, de->name, len); | |
37 | } | |
38 | ||
1da177e4 LT |
39 | /* buffer size is one page but our output routines use some slack for overruns */ |
40 | #define PROC_BLOCK_SIZE (PAGE_SIZE - 1024) | |
41 | ||
42 | static ssize_t | |
3dec7f59 | 43 | __proc_file_read(struct file *file, char __user *buf, size_t nbytes, |
1da177e4 LT |
44 | loff_t *ppos) |
45 | { | |
496ad9aa | 46 | struct inode * inode = file_inode(file); |
1da177e4 LT |
47 | char *page; |
48 | ssize_t retval=0; | |
49 | int eof=0; | |
50 | ssize_t n, count; | |
51 | char *start; | |
52 | struct proc_dir_entry * dp; | |
8b90db0d LT |
53 | unsigned long long pos; |
54 | ||
55 | /* | |
56 | * Gaah, please just use "seq_file" instead. The legacy /proc | |
57 | * interfaces cut loff_t down to off_t for reads, and ignore | |
58 | * the offset entirely for writes.. | |
59 | */ | |
60 | pos = *ppos; | |
61 | if (pos > MAX_NON_LFS) | |
62 | return 0; | |
63 | if (nbytes > MAX_NON_LFS - pos) | |
64 | nbytes = MAX_NON_LFS - pos; | |
1da177e4 LT |
65 | |
66 | dp = PDE(inode); | |
e12ba74d | 67 | if (!(page = (char*) __get_free_page(GFP_TEMPORARY))) |
1da177e4 LT |
68 | return -ENOMEM; |
69 | ||
70 | while ((nbytes > 0) && !eof) { | |
71 | count = min_t(size_t, PROC_BLOCK_SIZE, nbytes); | |
72 | ||
73 | start = NULL; | |
8731f14d | 74 | if (dp->read_proc) { |
1da177e4 LT |
75 | /* |
76 | * How to be a proc read function | |
77 | * ------------------------------ | |
78 | * Prototype: | |
79 | * int f(char *buffer, char **start, off_t offset, | |
80 | * int count, int *peof, void *dat) | |
81 | * | |
82 | * Assume that the buffer is "count" bytes in size. | |
83 | * | |
84 | * If you know you have supplied all the data you | |
85 | * have, set *peof. | |
86 | * | |
87 | * You have three ways to return data: | |
88 | * 0) Leave *start = NULL. (This is the default.) | |
89 | * Put the data of the requested offset at that | |
90 | * offset within the buffer. Return the number (n) | |
91 | * of bytes there are from the beginning of the | |
92 | * buffer up to the last byte of data. If the | |
93 | * number of supplied bytes (= n - offset) is | |
94 | * greater than zero and you didn't signal eof | |
95 | * and the reader is prepared to take more data | |
96 | * you will be called again with the requested | |
97 | * offset advanced by the number of bytes | |
98 | * absorbed. This interface is useful for files | |
99 | * no larger than the buffer. | |
100 | * 1) Set *start = an unsigned long value less than | |
101 | * the buffer address but greater than zero. | |
102 | * Put the data of the requested offset at the | |
103 | * beginning of the buffer. Return the number of | |
104 | * bytes of data placed there. If this number is | |
105 | * greater than zero and you didn't signal eof | |
106 | * and the reader is prepared to take more data | |
107 | * you will be called again with the requested | |
108 | * offset advanced by *start. This interface is | |
109 | * useful when you have a large file consisting | |
110 | * of a series of blocks which you want to count | |
111 | * and return as wholes. | |
112 | * (Hack by Paul.Russell@rustcorp.com.au) | |
113 | * 2) Set *start = an address within the buffer. | |
114 | * Put the data of the requested offset at *start. | |
115 | * Return the number of bytes of data placed there. | |
116 | * If this number is greater than zero and you | |
117 | * didn't signal eof and the reader is prepared to | |
118 | * take more data you will be called again with the | |
119 | * requested offset advanced by the number of bytes | |
120 | * absorbed. | |
121 | */ | |
122 | n = dp->read_proc(page, &start, *ppos, | |
123 | count, &eof, dp->data); | |
124 | } else | |
125 | break; | |
126 | ||
127 | if (n == 0) /* end of file */ | |
128 | break; | |
129 | if (n < 0) { /* error */ | |
130 | if (retval == 0) | |
131 | retval = n; | |
132 | break; | |
133 | } | |
134 | ||
135 | if (start == NULL) { | |
87ebdc00 | 136 | if (n > PAGE_SIZE) /* Apparent buffer overflow */ |
1da177e4 | 137 | n = PAGE_SIZE; |
1da177e4 LT |
138 | n -= *ppos; |
139 | if (n <= 0) | |
140 | break; | |
141 | if (n > count) | |
142 | n = count; | |
143 | start = page + *ppos; | |
144 | } else if (start < page) { | |
87ebdc00 | 145 | if (n > PAGE_SIZE) /* Apparent buffer overflow */ |
1da177e4 | 146 | n = PAGE_SIZE; |
1da177e4 LT |
147 | if (n > count) { |
148 | /* | |
149 | * Don't reduce n because doing so might | |
150 | * cut off part of a data block. | |
151 | */ | |
87ebdc00 | 152 | pr_warn("proc_file_read: count exceeded\n"); |
1da177e4 LT |
153 | } |
154 | } else /* start >= page */ { | |
155 | unsigned long startoff = (unsigned long)(start - page); | |
87ebdc00 | 156 | if (n > (PAGE_SIZE - startoff)) /* buffer overflow? */ |
1da177e4 | 157 | n = PAGE_SIZE - startoff; |
1da177e4 LT |
158 | if (n > count) |
159 | n = count; | |
160 | } | |
161 | ||
162 | n -= copy_to_user(buf, start < page ? page : start, n); | |
163 | if (n == 0) { | |
164 | if (retval == 0) | |
165 | retval = -EFAULT; | |
166 | break; | |
167 | } | |
168 | ||
169 | *ppos += start < page ? (unsigned long)start : n; | |
170 | nbytes -= n; | |
171 | buf += n; | |
172 | retval += n; | |
173 | } | |
174 | free_page((unsigned long) page); | |
175 | return retval; | |
176 | } | |
177 | ||
3dec7f59 AD |
178 | static ssize_t |
179 | proc_file_read(struct file *file, char __user *buf, size_t nbytes, | |
180 | loff_t *ppos) | |
181 | { | |
496ad9aa | 182 | struct proc_dir_entry *pde = PDE(file_inode(file)); |
3dec7f59 AD |
183 | ssize_t rv = -EIO; |
184 | ||
185 | spin_lock(&pde->pde_unload_lock); | |
186 | if (!pde->proc_fops) { | |
187 | spin_unlock(&pde->pde_unload_lock); | |
188 | return rv; | |
189 | } | |
190 | pde->pde_users++; | |
191 | spin_unlock(&pde->pde_unload_lock); | |
192 | ||
193 | rv = __proc_file_read(file, buf, nbytes, ppos); | |
194 | ||
195 | pde_users_dec(pde); | |
196 | return rv; | |
197 | } | |
198 | ||
1da177e4 LT |
199 | static ssize_t |
200 | proc_file_write(struct file *file, const char __user *buffer, | |
201 | size_t count, loff_t *ppos) | |
202 | { | |
496ad9aa | 203 | struct proc_dir_entry *pde = PDE(file_inode(file)); |
3dec7f59 AD |
204 | ssize_t rv = -EIO; |
205 | ||
206 | if (pde->write_proc) { | |
207 | spin_lock(&pde->pde_unload_lock); | |
208 | if (!pde->proc_fops) { | |
209 | spin_unlock(&pde->pde_unload_lock); | |
210 | return rv; | |
211 | } | |
212 | pde->pde_users++; | |
213 | spin_unlock(&pde->pde_unload_lock); | |
1da177e4 | 214 | |
3dec7f59 AD |
215 | /* FIXME: does this routine need ppos? probably... */ |
216 | rv = pde->write_proc(file, buffer, count, pde->data); | |
217 | pde_users_dec(pde); | |
218 | } | |
219 | return rv; | |
1da177e4 LT |
220 | } |
221 | ||
222 | ||
223 | static loff_t | |
224 | proc_file_lseek(struct file *file, loff_t offset, int orig) | |
225 | { | |
8b90db0d LT |
226 | loff_t retval = -EINVAL; |
227 | switch (orig) { | |
228 | case 1: | |
229 | offset += file->f_pos; | |
230 | /* fallthrough */ | |
231 | case 0: | |
232 | if (offset < 0 || offset > MAX_NON_LFS) | |
233 | break; | |
234 | file->f_pos = retval = offset; | |
235 | } | |
236 | return retval; | |
1da177e4 LT |
237 | } |
238 | ||
76df0c25 AD |
239 | static const struct file_operations proc_file_operations = { |
240 | .llseek = proc_file_lseek, | |
241 | .read = proc_file_read, | |
242 | .write = proc_file_write, | |
243 | }; | |
244 | ||
1da177e4 LT |
245 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) |
246 | { | |
247 | struct inode *inode = dentry->d_inode; | |
248 | struct proc_dir_entry *de = PDE(inode); | |
249 | int error; | |
250 | ||
251 | error = inode_change_ok(inode, iattr); | |
252 | if (error) | |
1025774c | 253 | return error; |
1da177e4 | 254 | |
1025774c CH |
255 | setattr_copy(inode, iattr); |
256 | mark_inode_dirty(inode); | |
46f69557 | 257 | |
1da177e4 LT |
258 | de->uid = inode->i_uid; |
259 | de->gid = inode->i_gid; | |
260 | de->mode = inode->i_mode; | |
1025774c | 261 | return 0; |
1da177e4 LT |
262 | } |
263 | ||
2b579bee MS |
264 | static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry, |
265 | struct kstat *stat) | |
266 | { | |
267 | struct inode *inode = dentry->d_inode; | |
268 | struct proc_dir_entry *de = PROC_I(inode)->pde; | |
269 | if (de && de->nlink) | |
bfe86848 | 270 | set_nlink(inode, de->nlink); |
2b579bee MS |
271 | |
272 | generic_fillattr(inode, stat); | |
273 | return 0; | |
274 | } | |
275 | ||
c5ef1c42 | 276 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
277 | .setattr = proc_notify_change, |
278 | }; | |
279 | ||
280 | /* | |
281 | * This function parses a name such as "tty/driver/serial", and | |
282 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
283 | * returns "serial" in residual. | |
284 | */ | |
e17a5765 AD |
285 | static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret, |
286 | const char **residual) | |
1da177e4 LT |
287 | { |
288 | const char *cp = name, *next; | |
289 | struct proc_dir_entry *de; | |
312ec7e5 | 290 | unsigned int len; |
1da177e4 | 291 | |
7cee4e00 AD |
292 | de = *ret; |
293 | if (!de) | |
294 | de = &proc_root; | |
295 | ||
1da177e4 LT |
296 | while (1) { |
297 | next = strchr(cp, '/'); | |
298 | if (!next) | |
299 | break; | |
300 | ||
301 | len = next - cp; | |
302 | for (de = de->subdir; de ; de = de->next) { | |
303 | if (proc_match(len, cp, de)) | |
304 | break; | |
305 | } | |
12bac0d9 AD |
306 | if (!de) { |
307 | WARN(1, "name '%s'\n", name); | |
e17a5765 | 308 | return -ENOENT; |
12bac0d9 | 309 | } |
1da177e4 LT |
310 | cp += len + 1; |
311 | } | |
312 | *residual = cp; | |
313 | *ret = de; | |
e17a5765 AD |
314 | return 0; |
315 | } | |
316 | ||
317 | static int xlate_proc_name(const char *name, struct proc_dir_entry **ret, | |
318 | const char **residual) | |
319 | { | |
320 | int rv; | |
321 | ||
322 | spin_lock(&proc_subdir_lock); | |
323 | rv = __xlate_proc_name(name, ret, residual); | |
64a07bd8 | 324 | spin_unlock(&proc_subdir_lock); |
e17a5765 | 325 | return rv; |
1da177e4 LT |
326 | } |
327 | ||
9a185409 | 328 | static DEFINE_IDA(proc_inum_ida); |
1da177e4 LT |
329 | static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ |
330 | ||
67935df4 | 331 | #define PROC_DYNAMIC_FIRST 0xF0000000U |
1da177e4 LT |
332 | |
333 | /* | |
334 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
335 | * 0xffffffff, or zero on failure. | |
336 | */ | |
33d6dce6 | 337 | int proc_alloc_inum(unsigned int *inum) |
1da177e4 | 338 | { |
67935df4 | 339 | unsigned int i; |
1da177e4 LT |
340 | int error; |
341 | ||
342 | retry: | |
33d6dce6 EB |
343 | if (!ida_pre_get(&proc_inum_ida, GFP_KERNEL)) |
344 | return -ENOMEM; | |
1da177e4 | 345 | |
dfb2ea45 | 346 | spin_lock_irq(&proc_inum_lock); |
9a185409 | 347 | error = ida_get_new(&proc_inum_ida, &i); |
dfb2ea45 | 348 | spin_unlock_irq(&proc_inum_lock); |
1da177e4 LT |
349 | if (error == -EAGAIN) |
350 | goto retry; | |
351 | else if (error) | |
33d6dce6 | 352 | return error; |
1da177e4 | 353 | |
67935df4 | 354 | if (i > UINT_MAX - PROC_DYNAMIC_FIRST) { |
dfb2ea45 | 355 | spin_lock_irq(&proc_inum_lock); |
9a185409 | 356 | ida_remove(&proc_inum_ida, i); |
dfb2ea45 | 357 | spin_unlock_irq(&proc_inum_lock); |
33d6dce6 | 358 | return -ENOSPC; |
67935df4 | 359 | } |
33d6dce6 EB |
360 | *inum = PROC_DYNAMIC_FIRST + i; |
361 | return 0; | |
1da177e4 LT |
362 | } |
363 | ||
33d6dce6 | 364 | void proc_free_inum(unsigned int inum) |
1da177e4 | 365 | { |
dfb2ea45 EB |
366 | unsigned long flags; |
367 | spin_lock_irqsave(&proc_inum_lock, flags); | |
9a185409 | 368 | ida_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); |
dfb2ea45 | 369 | spin_unlock_irqrestore(&proc_inum_lock, flags); |
1da177e4 LT |
370 | } |
371 | ||
008b150a | 372 | static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
373 | { |
374 | nd_set_link(nd, PDE(dentry->d_inode)->data); | |
008b150a | 375 | return NULL; |
1da177e4 LT |
376 | } |
377 | ||
c5ef1c42 | 378 | static const struct inode_operations proc_link_inode_operations = { |
1da177e4 LT |
379 | .readlink = generic_readlink, |
380 | .follow_link = proc_follow_link, | |
381 | }; | |
382 | ||
383 | /* | |
384 | * As some entries in /proc are volatile, we want to | |
385 | * get rid of unused dentries. This could be made | |
386 | * smarter: we could keep a "volatile" flag in the | |
387 | * inode to indicate which ones to keep. | |
388 | */ | |
fe15ce44 | 389 | static int proc_delete_dentry(const struct dentry * dentry) |
1da177e4 LT |
390 | { |
391 | return 1; | |
392 | } | |
393 | ||
d72f71eb | 394 | static const struct dentry_operations proc_dentry_operations = |
1da177e4 LT |
395 | { |
396 | .d_delete = proc_delete_dentry, | |
397 | }; | |
398 | ||
399 | /* | |
400 | * Don't create negative dentries here, return -ENOENT by hand | |
401 | * instead. | |
402 | */ | |
e9720acd PE |
403 | struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir, |
404 | struct dentry *dentry) | |
1da177e4 | 405 | { |
d3d009cb | 406 | struct inode *inode; |
1da177e4 | 407 | |
64a07bd8 | 408 | spin_lock(&proc_subdir_lock); |
5e971dce AD |
409 | for (de = de->subdir; de ; de = de->next) { |
410 | if (de->namelen != dentry->d_name.len) | |
411 | continue; | |
412 | if (!memcmp(dentry->d_name.name, de->name, de->namelen)) { | |
135d5655 | 413 | pde_get(de); |
5e971dce | 414 | spin_unlock(&proc_subdir_lock); |
6d1b6e4e | 415 | inode = proc_get_inode(dir->i_sb, de); |
d3d009cb AV |
416 | if (!inode) |
417 | return ERR_PTR(-ENOMEM); | |
418 | d_set_d_op(dentry, &proc_dentry_operations); | |
419 | d_add(dentry, inode); | |
420 | return NULL; | |
1da177e4 LT |
421 | } |
422 | } | |
64a07bd8 | 423 | spin_unlock(&proc_subdir_lock); |
d3d009cb | 424 | return ERR_PTR(-ENOENT); |
1da177e4 LT |
425 | } |
426 | ||
e9720acd | 427 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 428 | unsigned int flags) |
e9720acd PE |
429 | { |
430 | return proc_lookup_de(PDE(dir), dir, dentry); | |
431 | } | |
432 | ||
1da177e4 LT |
433 | /* |
434 | * This returns non-zero if at EOF, so that the /proc | |
435 | * root directory can use this and check if it should | |
436 | * continue with the <pid> entries.. | |
437 | * | |
438 | * Note that the VFS-layer doesn't care about the return | |
439 | * value of the readdir() call, as long as it's non-negative | |
440 | * for success.. | |
441 | */ | |
e9720acd PE |
442 | int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent, |
443 | filldir_t filldir) | |
1da177e4 | 444 | { |
1da177e4 LT |
445 | unsigned int ino; |
446 | int i; | |
496ad9aa | 447 | struct inode *inode = file_inode(filp); |
1da177e4 LT |
448 | int ret = 0; |
449 | ||
1da177e4 | 450 | ino = inode->i_ino; |
1da177e4 LT |
451 | i = filp->f_pos; |
452 | switch (i) { | |
453 | case 0: | |
454 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
455 | goto out; | |
456 | i++; | |
457 | filp->f_pos++; | |
458 | /* fall through */ | |
459 | case 1: | |
460 | if (filldir(dirent, "..", 2, i, | |
2fddfeef | 461 | parent_ino(filp->f_path.dentry), |
1da177e4 LT |
462 | DT_DIR) < 0) |
463 | goto out; | |
464 | i++; | |
465 | filp->f_pos++; | |
466 | /* fall through */ | |
467 | default: | |
64a07bd8 | 468 | spin_lock(&proc_subdir_lock); |
1da177e4 LT |
469 | de = de->subdir; |
470 | i -= 2; | |
471 | for (;;) { | |
472 | if (!de) { | |
473 | ret = 1; | |
64a07bd8 | 474 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
475 | goto out; |
476 | } | |
477 | if (!i) | |
478 | break; | |
479 | de = de->next; | |
480 | i--; | |
481 | } | |
482 | ||
483 | do { | |
59cd0cbc DW |
484 | struct proc_dir_entry *next; |
485 | ||
64a07bd8 | 486 | /* filldir passes info to user space */ |
135d5655 | 487 | pde_get(de); |
64a07bd8 | 488 | spin_unlock(&proc_subdir_lock); |
1da177e4 | 489 | if (filldir(dirent, de->name, de->namelen, filp->f_pos, |
59cd0cbc | 490 | de->low_ino, de->mode >> 12) < 0) { |
135d5655 | 491 | pde_put(de); |
1da177e4 | 492 | goto out; |
59cd0cbc | 493 | } |
64a07bd8 | 494 | spin_lock(&proc_subdir_lock); |
1da177e4 | 495 | filp->f_pos++; |
59cd0cbc | 496 | next = de->next; |
135d5655 | 497 | pde_put(de); |
59cd0cbc | 498 | de = next; |
1da177e4 | 499 | } while (de); |
64a07bd8 | 500 | spin_unlock(&proc_subdir_lock); |
1da177e4 LT |
501 | } |
502 | ret = 1; | |
b4df2b92 | 503 | out: |
1da177e4 LT |
504 | return ret; |
505 | } | |
506 | ||
e9720acd PE |
507 | int proc_readdir(struct file *filp, void *dirent, filldir_t filldir) |
508 | { | |
496ad9aa | 509 | struct inode *inode = file_inode(filp); |
e9720acd PE |
510 | |
511 | return proc_readdir_de(PDE(inode), filp, dirent, filldir); | |
512 | } | |
513 | ||
1da177e4 LT |
514 | /* |
515 | * These are the generic /proc directory operations. They | |
516 | * use the in-memory "struct proc_dir_entry" tree to parse | |
517 | * the /proc directory. | |
518 | */ | |
00977a59 | 519 | static const struct file_operations proc_dir_operations = { |
b4df2b92 | 520 | .llseek = generic_file_llseek, |
1da177e4 LT |
521 | .read = generic_read_dir, |
522 | .readdir = proc_readdir, | |
523 | }; | |
524 | ||
525 | /* | |
526 | * proc directories can do almost nothing.. | |
527 | */ | |
c5ef1c42 | 528 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 529 | .lookup = proc_lookup, |
2b579bee | 530 | .getattr = proc_getattr, |
1da177e4 LT |
531 | .setattr = proc_notify_change, |
532 | }; | |
533 | ||
534 | static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) | |
535 | { | |
94413d88 | 536 | struct proc_dir_entry *tmp; |
33d6dce6 | 537 | int ret; |
1da177e4 | 538 | |
33d6dce6 EB |
539 | ret = proc_alloc_inum(&dp->low_ino); |
540 | if (ret) | |
541 | return ret; | |
64a07bd8 | 542 | |
1da177e4 LT |
543 | if (S_ISDIR(dp->mode)) { |
544 | if (dp->proc_iops == NULL) { | |
545 | dp->proc_fops = &proc_dir_operations; | |
546 | dp->proc_iops = &proc_dir_inode_operations; | |
547 | } | |
548 | dir->nlink++; | |
549 | } else if (S_ISLNK(dp->mode)) { | |
550 | if (dp->proc_iops == NULL) | |
551 | dp->proc_iops = &proc_link_inode_operations; | |
552 | } else if (S_ISREG(dp->mode)) { | |
553 | if (dp->proc_fops == NULL) | |
554 | dp->proc_fops = &proc_file_operations; | |
555 | if (dp->proc_iops == NULL) | |
556 | dp->proc_iops = &proc_file_inode_operations; | |
557 | } | |
99fc06df CG |
558 | |
559 | spin_lock(&proc_subdir_lock); | |
94413d88 ZR |
560 | |
561 | for (tmp = dir->subdir; tmp; tmp = tmp->next) | |
562 | if (strcmp(tmp->name, dp->name) == 0) { | |
87ebdc00 | 563 | WARN(1, "proc_dir_entry '%s/%s' already registered\n", |
665020c3 | 564 | dir->name, dp->name); |
94413d88 ZR |
565 | break; |
566 | } | |
567 | ||
99fc06df CG |
568 | dp->next = dir->subdir; |
569 | dp->parent = dir; | |
570 | dir->subdir = dp; | |
571 | spin_unlock(&proc_subdir_lock); | |
572 | ||
1da177e4 LT |
573 | return 0; |
574 | } | |
575 | ||
2d3a4e36 | 576 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 | 577 | const char *name, |
d161a13f | 578 | umode_t mode, |
1da177e4 LT |
579 | nlink_t nlink) |
580 | { | |
581 | struct proc_dir_entry *ent = NULL; | |
582 | const char *fn = name; | |
312ec7e5 | 583 | unsigned int len; |
1da177e4 LT |
584 | |
585 | /* make sure name is valid */ | |
17baa2a2 | 586 | if (!name || !strlen(name)) |
587 | goto out; | |
1da177e4 | 588 | |
7cee4e00 | 589 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 LT |
590 | goto out; |
591 | ||
592 | /* At this point there must not be any '/' characters beyond *fn */ | |
593 | if (strchr(fn, '/')) | |
594 | goto out; | |
595 | ||
596 | len = strlen(fn); | |
597 | ||
17baa2a2 | 598 | ent = kzalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL); |
599 | if (!ent) | |
600 | goto out; | |
1da177e4 | 601 | |
09570f91 | 602 | memcpy(ent->name, fn, len + 1); |
1da177e4 LT |
603 | ent->namelen = len; |
604 | ent->mode = mode; | |
605 | ent->nlink = nlink; | |
5a622f2d | 606 | atomic_set(&ent->count, 1); |
786d7e16 | 607 | spin_lock_init(&ent->pde_unload_lock); |
881adb85 | 608 | INIT_LIST_HEAD(&ent->pde_openers); |
17baa2a2 | 609 | out: |
1da177e4 LT |
610 | return ent; |
611 | } | |
612 | ||
613 | struct proc_dir_entry *proc_symlink(const char *name, | |
614 | struct proc_dir_entry *parent, const char *dest) | |
615 | { | |
616 | struct proc_dir_entry *ent; | |
617 | ||
2d3a4e36 | 618 | ent = __proc_create(&parent, name, |
1da177e4 LT |
619 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
620 | ||
621 | if (ent) { | |
622 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
623 | if (ent->data) { | |
624 | strcpy((char*)ent->data,dest); | |
625 | if (proc_register(parent, ent) < 0) { | |
626 | kfree(ent->data); | |
627 | kfree(ent); | |
628 | ent = NULL; | |
629 | } | |
630 | } else { | |
631 | kfree(ent); | |
632 | ent = NULL; | |
633 | } | |
634 | } | |
635 | return ent; | |
636 | } | |
587d4a17 | 637 | EXPORT_SYMBOL(proc_symlink); |
1da177e4 | 638 | |
d161a13f | 639 | struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode, |
1da177e4 LT |
640 | struct proc_dir_entry *parent) |
641 | { | |
642 | struct proc_dir_entry *ent; | |
643 | ||
2d3a4e36 | 644 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 645 | if (ent) { |
1da177e4 LT |
646 | if (proc_register(parent, ent) < 0) { |
647 | kfree(ent); | |
648 | ent = NULL; | |
649 | } | |
650 | } | |
651 | return ent; | |
652 | } | |
011159a0 | 653 | EXPORT_SYMBOL(proc_mkdir_mode); |
1da177e4 | 654 | |
78e92b99 DL |
655 | struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name, |
656 | struct proc_dir_entry *parent) | |
657 | { | |
658 | struct proc_dir_entry *ent; | |
659 | ||
660 | ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2); | |
661 | if (ent) { | |
662 | ent->data = net; | |
663 | if (proc_register(parent, ent) < 0) { | |
664 | kfree(ent); | |
665 | ent = NULL; | |
666 | } | |
667 | } | |
668 | return ent; | |
669 | } | |
670 | EXPORT_SYMBOL_GPL(proc_net_mkdir); | |
671 | ||
1da177e4 LT |
672 | struct proc_dir_entry *proc_mkdir(const char *name, |
673 | struct proc_dir_entry *parent) | |
674 | { | |
675 | return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); | |
676 | } | |
587d4a17 | 677 | EXPORT_SYMBOL(proc_mkdir); |
1da177e4 | 678 | |
d161a13f | 679 | struct proc_dir_entry *create_proc_entry(const char *name, umode_t mode, |
1da177e4 LT |
680 | struct proc_dir_entry *parent) |
681 | { | |
682 | struct proc_dir_entry *ent; | |
683 | nlink_t nlink; | |
684 | ||
685 | if (S_ISDIR(mode)) { | |
686 | if ((mode & S_IALLUGO) == 0) | |
687 | mode |= S_IRUGO | S_IXUGO; | |
688 | nlink = 2; | |
689 | } else { | |
690 | if ((mode & S_IFMT) == 0) | |
691 | mode |= S_IFREG; | |
692 | if ((mode & S_IALLUGO) == 0) | |
693 | mode |= S_IRUGO; | |
694 | nlink = 1; | |
695 | } | |
696 | ||
2d3a4e36 | 697 | ent = __proc_create(&parent, name, mode, nlink); |
1da177e4 | 698 | if (ent) { |
1da177e4 LT |
699 | if (proc_register(parent, ent) < 0) { |
700 | kfree(ent); | |
701 | ent = NULL; | |
702 | } | |
703 | } | |
704 | return ent; | |
705 | } | |
587d4a17 | 706 | EXPORT_SYMBOL(create_proc_entry); |
1da177e4 | 707 | |
d161a13f | 708 | struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, |
59b74351 DL |
709 | struct proc_dir_entry *parent, |
710 | const struct file_operations *proc_fops, | |
711 | void *data) | |
2d3a4e36 AD |
712 | { |
713 | struct proc_dir_entry *pde; | |
714 | nlink_t nlink; | |
715 | ||
716 | if (S_ISDIR(mode)) { | |
717 | if ((mode & S_IALLUGO) == 0) | |
718 | mode |= S_IRUGO | S_IXUGO; | |
719 | nlink = 2; | |
720 | } else { | |
721 | if ((mode & S_IFMT) == 0) | |
722 | mode |= S_IFREG; | |
723 | if ((mode & S_IALLUGO) == 0) | |
724 | mode |= S_IRUGO; | |
725 | nlink = 1; | |
726 | } | |
727 | ||
728 | pde = __proc_create(&parent, name, mode, nlink); | |
729 | if (!pde) | |
730 | goto out; | |
731 | pde->proc_fops = proc_fops; | |
59b74351 | 732 | pde->data = data; |
2d3a4e36 AD |
733 | if (proc_register(parent, pde) < 0) |
734 | goto out_free; | |
735 | return pde; | |
736 | out_free: | |
737 | kfree(pde); | |
738 | out: | |
739 | return NULL; | |
740 | } | |
587d4a17 | 741 | EXPORT_SYMBOL(proc_create_data); |
2d3a4e36 | 742 | |
135d5655 | 743 | static void free_proc_entry(struct proc_dir_entry *de) |
1da177e4 | 744 | { |
33d6dce6 | 745 | proc_free_inum(de->low_ino); |
1da177e4 | 746 | |
fd2cbe48 | 747 | if (S_ISLNK(de->mode)) |
1da177e4 LT |
748 | kfree(de->data); |
749 | kfree(de); | |
750 | } | |
751 | ||
135d5655 AD |
752 | void pde_put(struct proc_dir_entry *pde) |
753 | { | |
754 | if (atomic_dec_and_test(&pde->count)) | |
755 | free_proc_entry(pde); | |
756 | } | |
757 | ||
1da177e4 LT |
758 | /* |
759 | * Remove a /proc entry and free it if it's not currently in use. | |
1da177e4 LT |
760 | */ |
761 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
762 | { | |
763 | struct proc_dir_entry **p; | |
f649d6d3 | 764 | struct proc_dir_entry *de = NULL; |
1da177e4 | 765 | const char *fn = name; |
312ec7e5 | 766 | unsigned int len; |
1da177e4 | 767 | |
e17a5765 AD |
768 | spin_lock(&proc_subdir_lock); |
769 | if (__xlate_proc_name(name, &parent, &fn) != 0) { | |
770 | spin_unlock(&proc_subdir_lock); | |
f649d6d3 | 771 | return; |
e17a5765 | 772 | } |
1da177e4 | 773 | len = strlen(fn); |
64a07bd8 | 774 | |
1da177e4 | 775 | for (p = &parent->subdir; *p; p=&(*p)->next ) { |
f649d6d3 AD |
776 | if (proc_match(len, fn, *p)) { |
777 | de = *p; | |
778 | *p = de->next; | |
779 | de->next = NULL; | |
780 | break; | |
781 | } | |
782 | } | |
783 | spin_unlock(&proc_subdir_lock); | |
12bac0d9 AD |
784 | if (!de) { |
785 | WARN(1, "name '%s'\n", name); | |
f649d6d3 | 786 | return; |
12bac0d9 | 787 | } |
786d7e16 | 788 | |
f649d6d3 AD |
789 | spin_lock(&de->pde_unload_lock); |
790 | /* | |
791 | * Stop accepting new callers into module. If you're | |
792 | * dynamically allocating ->proc_fops, save a pointer somewhere. | |
793 | */ | |
794 | de->proc_fops = NULL; | |
795 | /* Wait until all existing callers into module are done. */ | |
796 | if (de->pde_users > 0) { | |
797 | DECLARE_COMPLETION_ONSTACK(c); | |
798 | ||
799 | if (!de->pde_unload_completion) | |
800 | de->pde_unload_completion = &c; | |
786d7e16 | 801 | |
786d7e16 AD |
802 | spin_unlock(&de->pde_unload_lock); |
803 | ||
f649d6d3 AD |
804 | wait_for_completion(de->pde_unload_completion); |
805 | ||
3740a20c | 806 | spin_lock(&de->pde_unload_lock); |
f649d6d3 | 807 | } |
f649d6d3 | 808 | |
881adb85 AD |
809 | while (!list_empty(&de->pde_openers)) { |
810 | struct pde_opener *pdeo; | |
811 | ||
812 | pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh); | |
813 | list_del(&pdeo->lh); | |
814 | spin_unlock(&de->pde_unload_lock); | |
815 | pdeo->release(pdeo->inode, pdeo->file); | |
816 | kfree(pdeo); | |
817 | spin_lock(&de->pde_unload_lock); | |
818 | } | |
819 | spin_unlock(&de->pde_unload_lock); | |
820 | ||
f649d6d3 AD |
821 | if (S_ISDIR(de->mode)) |
822 | parent->nlink--; | |
823 | de->nlink = 0; | |
87ebdc00 AM |
824 | WARN(de->subdir, "%s: removing non-empty directory " |
825 | "'%s/%s', leaking at least '%s'\n", __func__, | |
826 | de->parent->name, de->name, de->subdir->name); | |
135d5655 | 827 | pde_put(de); |
1da177e4 | 828 | } |
587d4a17 | 829 | EXPORT_SYMBOL(remove_proc_entry); |