Commit | Line | Data |
---|---|---|
457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * proc/fs/generic.c --- generic routines for the proc-fs | |
4 | * | |
5 | * This file contains generic proc-fs routines for handling | |
6 | * directories and files. | |
7 | * | |
8 | * Copyright (C) 1991, 1992 Linus Torvalds. | |
9 | * Copyright (C) 1997 Theodore Ts'o | |
10 | */ | |
11 | ||
b4884f23 | 12 | #include <linux/cache.h> |
1da177e4 LT |
13 | #include <linux/errno.h> |
14 | #include <linux/time.h> | |
15 | #include <linux/proc_fs.h> | |
16 | #include <linux/stat.h> | |
1025774c | 17 | #include <linux/mm.h> |
1da177e4 | 18 | #include <linux/module.h> |
1da4d377 | 19 | #include <linux/namei.h> |
5a0e3ad6 | 20 | #include <linux/slab.h> |
87ebdc00 | 21 | #include <linux/printk.h> |
1da177e4 | 22 | #include <linux/mount.h> |
1da177e4 LT |
23 | #include <linux/init.h> |
24 | #include <linux/idr.h> | |
1da177e4 | 25 | #include <linux/bitops.h> |
64a07bd8 | 26 | #include <linux/spinlock.h> |
786d7e16 | 27 | #include <linux/completion.h> |
7c0f6ba6 | 28 | #include <linux/uaccess.h> |
fddda2b7 | 29 | #include <linux/seq_file.h> |
1da177e4 | 30 | |
fee781e6 AB |
31 | #include "internal.h" |
32 | ||
ecf1a3df | 33 | static DEFINE_RWLOCK(proc_subdir_lock); |
64a07bd8 | 34 | |
b4884f23 AD |
35 | struct kmem_cache *proc_dir_entry_cache __ro_after_init; |
36 | ||
37 | void pde_free(struct proc_dir_entry *pde) | |
38 | { | |
39 | if (S_ISLNK(pde->mode)) | |
40 | kfree(pde->data); | |
41 | if (pde->name != pde->inline_name) | |
42 | kfree(pde->name); | |
43 | kmem_cache_free(proc_dir_entry_cache, pde); | |
44 | } | |
45 | ||
93ad5bc6 | 46 | static int proc_match(const char *name, struct proc_dir_entry *de, unsigned int len) |
1da177e4 | 47 | { |
710585d4 ND |
48 | if (len < de->namelen) |
49 | return -1; | |
50 | if (len > de->namelen) | |
51 | return 1; | |
52 | ||
53 | return memcmp(name, de->name, len); | |
54 | } | |
55 | ||
56 | static struct proc_dir_entry *pde_subdir_first(struct proc_dir_entry *dir) | |
57 | { | |
4f113437 AD |
58 | return rb_entry_safe(rb_first(&dir->subdir), struct proc_dir_entry, |
59 | subdir_node); | |
710585d4 ND |
60 | } |
61 | ||
62 | static struct proc_dir_entry *pde_subdir_next(struct proc_dir_entry *dir) | |
63 | { | |
2fc1e948 ND |
64 | return rb_entry_safe(rb_next(&dir->subdir_node), struct proc_dir_entry, |
65 | subdir_node); | |
710585d4 ND |
66 | } |
67 | ||
68 | static struct proc_dir_entry *pde_subdir_find(struct proc_dir_entry *dir, | |
69 | const char *name, | |
70 | unsigned int len) | |
71 | { | |
4f113437 | 72 | struct rb_node *node = dir->subdir.rb_node; |
710585d4 ND |
73 | |
74 | while (node) { | |
4e4a7fb7 GT |
75 | struct proc_dir_entry *de = rb_entry(node, |
76 | struct proc_dir_entry, | |
77 | subdir_node); | |
93ad5bc6 | 78 | int result = proc_match(name, de, len); |
710585d4 ND |
79 | |
80 | if (result < 0) | |
81 | node = node->rb_left; | |
82 | else if (result > 0) | |
83 | node = node->rb_right; | |
84 | else | |
85 | return de; | |
86 | } | |
87 | return NULL; | |
88 | } | |
89 | ||
90 | static bool pde_subdir_insert(struct proc_dir_entry *dir, | |
91 | struct proc_dir_entry *de) | |
92 | { | |
4f113437 AD |
93 | struct rb_root *root = &dir->subdir; |
94 | struct rb_node **new = &root->rb_node, *parent = NULL; | |
710585d4 ND |
95 | |
96 | /* Figure out where to put new node */ | |
97 | while (*new) { | |
4e4a7fb7 GT |
98 | struct proc_dir_entry *this = rb_entry(*new, |
99 | struct proc_dir_entry, | |
100 | subdir_node); | |
93ad5bc6 | 101 | int result = proc_match(de->name, this, de->namelen); |
710585d4 ND |
102 | |
103 | parent = *new; | |
104 | if (result < 0) | |
105 | new = &(*new)->rb_left; | |
4f113437 | 106 | else if (result > 0) |
710585d4 | 107 | new = &(*new)->rb_right; |
4f113437 | 108 | else |
710585d4 ND |
109 | return false; |
110 | } | |
111 | ||
112 | /* Add new node and rebalance tree. */ | |
113 | rb_link_node(&de->subdir_node, parent, new); | |
4f113437 | 114 | rb_insert_color(&de->subdir_node, root); |
710585d4 | 115 | return true; |
1da177e4 LT |
116 | } |
117 | ||
1da177e4 LT |
118 | static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) |
119 | { | |
2b0143b5 | 120 | struct inode *inode = d_inode(dentry); |
1da177e4 LT |
121 | struct proc_dir_entry *de = PDE(inode); |
122 | int error; | |
123 | ||
31051c85 | 124 | error = setattr_prepare(dentry, iattr); |
1da177e4 | 125 | if (error) |
1025774c | 126 | return error; |
1da177e4 | 127 | |
1025774c CH |
128 | setattr_copy(inode, iattr); |
129 | mark_inode_dirty(inode); | |
46f69557 | 130 | |
cdf7e8dd | 131 | proc_set_user(de, inode->i_uid, inode->i_gid); |
1da177e4 | 132 | de->mode = inode->i_mode; |
1025774c | 133 | return 0; |
1da177e4 LT |
134 | } |
135 | ||
a528d35e DH |
136 | static int proc_getattr(const struct path *path, struct kstat *stat, |
137 | u32 request_mask, unsigned int query_flags) | |
2b579bee | 138 | { |
a528d35e | 139 | struct inode *inode = d_inode(path->dentry); |
6bee55f9 | 140 | struct proc_dir_entry *de = PDE(inode); |
2b579bee | 141 | if (de && de->nlink) |
bfe86848 | 142 | set_nlink(inode, de->nlink); |
2b579bee MS |
143 | |
144 | generic_fillattr(inode, stat); | |
145 | return 0; | |
146 | } | |
147 | ||
c5ef1c42 | 148 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
149 | .setattr = proc_notify_change, |
150 | }; | |
151 | ||
152 | /* | |
153 | * This function parses a name such as "tty/driver/serial", and | |
154 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
155 | * returns "serial" in residual. | |
156 | */ | |
e17a5765 AD |
157 | static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret, |
158 | const char **residual) | |
1da177e4 LT |
159 | { |
160 | const char *cp = name, *next; | |
161 | struct proc_dir_entry *de; | |
312ec7e5 | 162 | unsigned int len; |
1da177e4 | 163 | |
7cee4e00 AD |
164 | de = *ret; |
165 | if (!de) | |
166 | de = &proc_root; | |
167 | ||
1da177e4 LT |
168 | while (1) { |
169 | next = strchr(cp, '/'); | |
170 | if (!next) | |
171 | break; | |
172 | ||
173 | len = next - cp; | |
710585d4 | 174 | de = pde_subdir_find(de, cp, len); |
12bac0d9 AD |
175 | if (!de) { |
176 | WARN(1, "name '%s'\n", name); | |
e17a5765 | 177 | return -ENOENT; |
12bac0d9 | 178 | } |
1da177e4 LT |
179 | cp += len + 1; |
180 | } | |
181 | *residual = cp; | |
182 | *ret = de; | |
e17a5765 AD |
183 | return 0; |
184 | } | |
185 | ||
186 | static int xlate_proc_name(const char *name, struct proc_dir_entry **ret, | |
187 | const char **residual) | |
188 | { | |
189 | int rv; | |
190 | ||
ecf1a3df | 191 | read_lock(&proc_subdir_lock); |
e17a5765 | 192 | rv = __xlate_proc_name(name, ret, residual); |
ecf1a3df | 193 | read_unlock(&proc_subdir_lock); |
e17a5765 | 194 | return rv; |
1da177e4 LT |
195 | } |
196 | ||
9a185409 | 197 | static DEFINE_IDA(proc_inum_ida); |
1da177e4 | 198 | |
67935df4 | 199 | #define PROC_DYNAMIC_FIRST 0xF0000000U |
1da177e4 LT |
200 | |
201 | /* | |
202 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
203 | * 0xffffffff, or zero on failure. | |
204 | */ | |
33d6dce6 | 205 | int proc_alloc_inum(unsigned int *inum) |
1da177e4 | 206 | { |
cde1b693 | 207 | int i; |
1da177e4 | 208 | |
cde1b693 HK |
209 | i = ida_simple_get(&proc_inum_ida, 0, UINT_MAX - PROC_DYNAMIC_FIRST + 1, |
210 | GFP_KERNEL); | |
211 | if (i < 0) | |
212 | return i; | |
1da177e4 | 213 | |
cde1b693 | 214 | *inum = PROC_DYNAMIC_FIRST + (unsigned int)i; |
33d6dce6 | 215 | return 0; |
1da177e4 LT |
216 | } |
217 | ||
33d6dce6 | 218 | void proc_free_inum(unsigned int inum) |
1da177e4 | 219 | { |
cde1b693 | 220 | ida_simple_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); |
1da177e4 LT |
221 | } |
222 | ||
1da4d377 AD |
223 | static int proc_misc_d_revalidate(struct dentry *dentry, unsigned int flags) |
224 | { | |
225 | if (flags & LOOKUP_RCU) | |
226 | return -ECHILD; | |
227 | ||
228 | if (atomic_read(&PDE(d_inode(dentry))->in_use) < 0) | |
229 | return 0; /* revalidate */ | |
230 | return 1; | |
231 | } | |
232 | ||
233 | static int proc_misc_d_delete(const struct dentry *dentry) | |
234 | { | |
235 | return atomic_read(&PDE(d_inode(dentry))->in_use) < 0; | |
236 | } | |
237 | ||
238 | static const struct dentry_operations proc_misc_dentry_ops = { | |
239 | .d_revalidate = proc_misc_d_revalidate, | |
240 | .d_delete = proc_misc_d_delete, | |
241 | }; | |
242 | ||
1da177e4 LT |
243 | /* |
244 | * Don't create negative dentries here, return -ENOENT by hand | |
245 | * instead. | |
246 | */ | |
93ad5bc6 AD |
247 | struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry, |
248 | struct proc_dir_entry *de) | |
1da177e4 | 249 | { |
d3d009cb | 250 | struct inode *inode; |
1da177e4 | 251 | |
ecf1a3df | 252 | read_lock(&proc_subdir_lock); |
710585d4 ND |
253 | de = pde_subdir_find(de, dentry->d_name.name, dentry->d_name.len); |
254 | if (de) { | |
255 | pde_get(de); | |
ecf1a3df | 256 | read_unlock(&proc_subdir_lock); |
710585d4 ND |
257 | inode = proc_get_inode(dir->i_sb, de); |
258 | if (!inode) | |
259 | return ERR_PTR(-ENOMEM); | |
1fde6f21 | 260 | d_set_d_op(dentry, de->proc_dops); |
888e2b03 | 261 | return d_splice_alias(inode, dentry); |
1da177e4 | 262 | } |
ecf1a3df | 263 | read_unlock(&proc_subdir_lock); |
d3d009cb | 264 | return ERR_PTR(-ENOENT); |
1da177e4 LT |
265 | } |
266 | ||
e9720acd | 267 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 268 | unsigned int flags) |
e9720acd | 269 | { |
93ad5bc6 | 270 | return proc_lookup_de(dir, dentry, PDE(dir)); |
e9720acd PE |
271 | } |
272 | ||
1da177e4 LT |
273 | /* |
274 | * This returns non-zero if at EOF, so that the /proc | |
275 | * root directory can use this and check if it should | |
276 | * continue with the <pid> entries.. | |
277 | * | |
278 | * Note that the VFS-layer doesn't care about the return | |
279 | * value of the readdir() call, as long as it's non-negative | |
280 | * for success.. | |
281 | */ | |
93ad5bc6 AD |
282 | int proc_readdir_de(struct file *file, struct dir_context *ctx, |
283 | struct proc_dir_entry *de) | |
1da177e4 | 284 | { |
1da177e4 | 285 | int i; |
f0c3b509 AV |
286 | |
287 | if (!dir_emit_dots(file, ctx)) | |
288 | return 0; | |
289 | ||
8d48b2e0 | 290 | i = ctx->pos - 2; |
ecf1a3df | 291 | read_lock(&proc_subdir_lock); |
710585d4 | 292 | de = pde_subdir_first(de); |
f0c3b509 AV |
293 | for (;;) { |
294 | if (!de) { | |
ecf1a3df | 295 | read_unlock(&proc_subdir_lock); |
f0c3b509 AV |
296 | return 0; |
297 | } | |
298 | if (!i) | |
299 | break; | |
710585d4 | 300 | de = pde_subdir_next(de); |
f0c3b509 | 301 | i--; |
1da177e4 | 302 | } |
f0c3b509 AV |
303 | |
304 | do { | |
305 | struct proc_dir_entry *next; | |
306 | pde_get(de); | |
ecf1a3df | 307 | read_unlock(&proc_subdir_lock); |
f0c3b509 AV |
308 | if (!dir_emit(ctx, de->name, de->namelen, |
309 | de->low_ino, de->mode >> 12)) { | |
310 | pde_put(de); | |
311 | return 0; | |
312 | } | |
f0c3b509 | 313 | ctx->pos++; |
8d48b2e0 | 314 | read_lock(&proc_subdir_lock); |
710585d4 | 315 | next = pde_subdir_next(de); |
f0c3b509 AV |
316 | pde_put(de); |
317 | de = next; | |
318 | } while (de); | |
ecf1a3df | 319 | read_unlock(&proc_subdir_lock); |
fd3930f7 | 320 | return 1; |
1da177e4 LT |
321 | } |
322 | ||
f0c3b509 | 323 | int proc_readdir(struct file *file, struct dir_context *ctx) |
e9720acd | 324 | { |
f0c3b509 | 325 | struct inode *inode = file_inode(file); |
e9720acd | 326 | |
93ad5bc6 | 327 | return proc_readdir_de(file, ctx, PDE(inode)); |
e9720acd PE |
328 | } |
329 | ||
1da177e4 LT |
330 | /* |
331 | * These are the generic /proc directory operations. They | |
332 | * use the in-memory "struct proc_dir_entry" tree to parse | |
333 | * the /proc directory. | |
334 | */ | |
00977a59 | 335 | static const struct file_operations proc_dir_operations = { |
b4df2b92 | 336 | .llseek = generic_file_llseek, |
1da177e4 | 337 | .read = generic_read_dir, |
f50752ea | 338 | .iterate_shared = proc_readdir, |
1da177e4 LT |
339 | }; |
340 | ||
341 | /* | |
342 | * proc directories can do almost nothing.. | |
343 | */ | |
c5ef1c42 | 344 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 345 | .lookup = proc_lookup, |
2b579bee | 346 | .getattr = proc_getattr, |
1da177e4 LT |
347 | .setattr = proc_notify_change, |
348 | }; | |
349 | ||
61172eae CH |
350 | /* returns the registered entry, or frees dp and returns NULL on failure */ |
351 | struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, | |
352 | struct proc_dir_entry *dp) | |
1da177e4 | 353 | { |
61172eae CH |
354 | if (proc_alloc_inum(&dp->low_ino)) |
355 | goto out_free_entry; | |
64a07bd8 | 356 | |
ecf1a3df | 357 | write_lock(&proc_subdir_lock); |
99fc06df | 358 | dp->parent = dir; |
b208d54b | 359 | if (pde_subdir_insert(dir, dp) == false) { |
710585d4 ND |
360 | WARN(1, "proc_dir_entry '%s/%s' already registered\n", |
361 | dir->name, dp->name); | |
ecf1a3df | 362 | write_unlock(&proc_subdir_lock); |
61172eae | 363 | goto out_free_inum; |
b208d54b | 364 | } |
ecf1a3df | 365 | write_unlock(&proc_subdir_lock); |
99fc06df | 366 | |
61172eae CH |
367 | return dp; |
368 | out_free_inum: | |
369 | proc_free_inum(dp->low_ino); | |
370 | out_free_entry: | |
371 | pde_free(dp); | |
372 | return NULL; | |
1da177e4 LT |
373 | } |
374 | ||
2d3a4e36 | 375 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 | 376 | const char *name, |
d161a13f | 377 | umode_t mode, |
1da177e4 LT |
378 | nlink_t nlink) |
379 | { | |
380 | struct proc_dir_entry *ent = NULL; | |
dbcdb504 AD |
381 | const char *fn; |
382 | struct qstr qstr; | |
1da177e4 | 383 | |
7cee4e00 | 384 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 | 385 | goto out; |
dbcdb504 AD |
386 | qstr.name = fn; |
387 | qstr.len = strlen(fn); | |
388 | if (qstr.len == 0 || qstr.len >= 256) { | |
389 | WARN(1, "name len %u\n", qstr.len); | |
390 | return NULL; | |
391 | } | |
b77d70db AD |
392 | if (qstr.len == 1 && fn[0] == '.') { |
393 | WARN(1, "name '.'\n"); | |
394 | return NULL; | |
395 | } | |
396 | if (qstr.len == 2 && fn[0] == '.' && fn[1] == '.') { | |
397 | WARN(1, "name '..'\n"); | |
398 | return NULL; | |
399 | } | |
dbcdb504 AD |
400 | if (*parent == &proc_root && name_to_int(&qstr) != ~0U) { |
401 | WARN(1, "create '/proc/%s' by hand\n", qstr.name); | |
402 | return NULL; | |
403 | } | |
eb6d38d5 EB |
404 | if (is_empty_pde(*parent)) { |
405 | WARN(1, "attempt to add to permanently empty directory"); | |
406 | return NULL; | |
407 | } | |
1da177e4 | 408 | |
b4884f23 | 409 | ent = kmem_cache_zalloc(proc_dir_entry_cache, GFP_KERNEL); |
17baa2a2 | 410 | if (!ent) |
411 | goto out; | |
1da177e4 | 412 | |
24074a35 | 413 | if (qstr.len + 1 <= SIZEOF_PDE_INLINE_NAME) { |
b4884f23 AD |
414 | ent->name = ent->inline_name; |
415 | } else { | |
416 | ent->name = kmalloc(qstr.len + 1, GFP_KERNEL); | |
417 | if (!ent->name) { | |
418 | pde_free(ent); | |
419 | return NULL; | |
420 | } | |
421 | } | |
422 | ||
dbcdb504 AD |
423 | memcpy(ent->name, fn, qstr.len + 1); |
424 | ent->namelen = qstr.len; | |
1da177e4 LT |
425 | ent->mode = mode; |
426 | ent->nlink = nlink; | |
4f113437 | 427 | ent->subdir = RB_ROOT; |
9cdd83e3 | 428 | refcount_set(&ent->refcnt, 1); |
786d7e16 | 429 | spin_lock_init(&ent->pde_unload_lock); |
881adb85 | 430 | INIT_LIST_HEAD(&ent->pde_openers); |
c110486f DT |
431 | proc_set_user(ent, (*parent)->uid, (*parent)->gid); |
432 | ||
1fde6f21 AD |
433 | ent->proc_dops = &proc_misc_dentry_ops; |
434 | ||
17baa2a2 | 435 | out: |
1da177e4 LT |
436 | return ent; |
437 | } | |
438 | ||
439 | struct proc_dir_entry *proc_symlink(const char *name, | |
440 | struct proc_dir_entry *parent, const char *dest) | |
441 | { | |
442 | struct proc_dir_entry *ent; | |
443 | ||
2d3a4e36 | 444 | ent = __proc_create(&parent, name, |
1da177e4 LT |
445 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
446 | ||
447 | if (ent) { | |
448 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
449 | if (ent->data) { | |
450 | strcpy((char*)ent->data,dest); | |
d443b9fd | 451 | ent->proc_iops = &proc_link_inode_operations; |
61172eae | 452 | ent = proc_register(parent, ent); |
1da177e4 | 453 | } else { |
b4884f23 | 454 | pde_free(ent); |
1da177e4 LT |
455 | ent = NULL; |
456 | } | |
457 | } | |
458 | return ent; | |
459 | } | |
587d4a17 | 460 | EXPORT_SYMBOL(proc_symlink); |
1da177e4 | 461 | |
270b5ac2 DH |
462 | struct proc_dir_entry *proc_mkdir_data(const char *name, umode_t mode, |
463 | struct proc_dir_entry *parent, void *data) | |
1da177e4 LT |
464 | { |
465 | struct proc_dir_entry *ent; | |
466 | ||
270b5ac2 DH |
467 | if (mode == 0) |
468 | mode = S_IRUGO | S_IXUGO; | |
469 | ||
2d3a4e36 | 470 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 471 | if (ent) { |
270b5ac2 | 472 | ent->data = data; |
d443b9fd AV |
473 | ent->proc_fops = &proc_dir_operations; |
474 | ent->proc_iops = &proc_dir_inode_operations; | |
475 | parent->nlink++; | |
61172eae CH |
476 | ent = proc_register(parent, ent); |
477 | if (!ent) | |
d443b9fd | 478 | parent->nlink--; |
1da177e4 LT |
479 | } |
480 | return ent; | |
481 | } | |
270b5ac2 | 482 | EXPORT_SYMBOL_GPL(proc_mkdir_data); |
1da177e4 | 483 | |
270b5ac2 DH |
484 | struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode, |
485 | struct proc_dir_entry *parent) | |
78e92b99 | 486 | { |
270b5ac2 | 487 | return proc_mkdir_data(name, mode, parent, NULL); |
78e92b99 | 488 | } |
270b5ac2 | 489 | EXPORT_SYMBOL(proc_mkdir_mode); |
78e92b99 | 490 | |
1da177e4 LT |
491 | struct proc_dir_entry *proc_mkdir(const char *name, |
492 | struct proc_dir_entry *parent) | |
493 | { | |
270b5ac2 | 494 | return proc_mkdir_data(name, 0, parent, NULL); |
1da177e4 | 495 | } |
587d4a17 | 496 | EXPORT_SYMBOL(proc_mkdir); |
1da177e4 | 497 | |
eb6d38d5 EB |
498 | struct proc_dir_entry *proc_create_mount_point(const char *name) |
499 | { | |
500 | umode_t mode = S_IFDIR | S_IRUGO | S_IXUGO; | |
501 | struct proc_dir_entry *ent, *parent = NULL; | |
502 | ||
503 | ent = __proc_create(&parent, name, mode, 2); | |
504 | if (ent) { | |
505 | ent->data = NULL; | |
506 | ent->proc_fops = NULL; | |
507 | ent->proc_iops = NULL; | |
d66bb160 | 508 | parent->nlink++; |
61172eae CH |
509 | ent = proc_register(parent, ent); |
510 | if (!ent) | |
eb6d38d5 | 511 | parent->nlink--; |
eb6d38d5 EB |
512 | } |
513 | return ent; | |
514 | } | |
f97df70b | 515 | EXPORT_SYMBOL(proc_create_mount_point); |
eb6d38d5 | 516 | |
7aed53d1 CH |
517 | struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode, |
518 | struct proc_dir_entry **parent, void *data) | |
2d3a4e36 | 519 | { |
7aed53d1 CH |
520 | struct proc_dir_entry *p; |
521 | ||
b6cdc731 AV |
522 | if ((mode & S_IFMT) == 0) |
523 | mode |= S_IFREG; | |
7aed53d1 CH |
524 | if ((mode & S_IALLUGO) == 0) |
525 | mode |= S_IRUGO; | |
526 | if (WARN_ON_ONCE(!S_ISREG(mode))) | |
b6cdc731 | 527 | return NULL; |
7aed53d1 CH |
528 | |
529 | p = __proc_create(parent, name, mode, 1); | |
530 | if (p) { | |
531 | p->proc_iops = &proc_file_inode_operations; | |
532 | p->data = data; | |
2d3a4e36 | 533 | } |
7aed53d1 CH |
534 | return p; |
535 | } | |
536 | ||
537 | struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, | |
538 | struct proc_dir_entry *parent, | |
539 | const struct file_operations *proc_fops, void *data) | |
540 | { | |
541 | struct proc_dir_entry *p; | |
2d3a4e36 | 542 | |
d443b9fd AV |
543 | BUG_ON(proc_fops == NULL); |
544 | ||
7aed53d1 CH |
545 | p = proc_create_reg(name, mode, &parent, data); |
546 | if (!p) | |
547 | return NULL; | |
548 | p->proc_fops = proc_fops; | |
549 | return proc_register(parent, p); | |
2d3a4e36 | 550 | } |
587d4a17 | 551 | EXPORT_SYMBOL(proc_create_data); |
271a15ea | 552 | |
855d9765 AD |
553 | struct proc_dir_entry *proc_create(const char *name, umode_t mode, |
554 | struct proc_dir_entry *parent, | |
555 | const struct file_operations *proc_fops) | |
556 | { | |
557 | return proc_create_data(name, mode, parent, proc_fops, NULL); | |
558 | } | |
559 | EXPORT_SYMBOL(proc_create); | |
560 | ||
fddda2b7 CH |
561 | static int proc_seq_open(struct inode *inode, struct file *file) |
562 | { | |
563 | struct proc_dir_entry *de = PDE(inode); | |
564 | ||
44414d82 CH |
565 | if (de->state_size) |
566 | return seq_open_private(file, de->seq_ops, de->state_size); | |
fddda2b7 CH |
567 | return seq_open(file, de->seq_ops); |
568 | } | |
569 | ||
877f919e CH |
570 | static int proc_seq_release(struct inode *inode, struct file *file) |
571 | { | |
572 | struct proc_dir_entry *de = PDE(inode); | |
573 | ||
574 | if (de->state_size) | |
575 | return seq_release_private(inode, file); | |
576 | return seq_release(inode, file); | |
577 | } | |
578 | ||
fddda2b7 CH |
579 | static const struct file_operations proc_seq_fops = { |
580 | .open = proc_seq_open, | |
581 | .read = seq_read, | |
582 | .llseek = seq_lseek, | |
877f919e | 583 | .release = proc_seq_release, |
fddda2b7 CH |
584 | }; |
585 | ||
44414d82 | 586 | struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode, |
fddda2b7 | 587 | struct proc_dir_entry *parent, const struct seq_operations *ops, |
44414d82 | 588 | unsigned int state_size, void *data) |
fddda2b7 CH |
589 | { |
590 | struct proc_dir_entry *p; | |
591 | ||
592 | p = proc_create_reg(name, mode, &parent, data); | |
593 | if (!p) | |
594 | return NULL; | |
595 | p->proc_fops = &proc_seq_fops; | |
596 | p->seq_ops = ops; | |
44414d82 | 597 | p->state_size = state_size; |
fddda2b7 CH |
598 | return proc_register(parent, p); |
599 | } | |
44414d82 | 600 | EXPORT_SYMBOL(proc_create_seq_private); |
fddda2b7 | 601 | |
3f3942ac CH |
602 | static int proc_single_open(struct inode *inode, struct file *file) |
603 | { | |
604 | struct proc_dir_entry *de = PDE(inode); | |
605 | ||
606 | return single_open(file, de->single_show, de->data); | |
607 | } | |
608 | ||
609 | static const struct file_operations proc_single_fops = { | |
610 | .open = proc_single_open, | |
611 | .read = seq_read, | |
612 | .llseek = seq_lseek, | |
613 | .release = single_release, | |
614 | }; | |
615 | ||
616 | struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode, | |
617 | struct proc_dir_entry *parent, | |
618 | int (*show)(struct seq_file *, void *), void *data) | |
619 | { | |
620 | struct proc_dir_entry *p; | |
621 | ||
622 | p = proc_create_reg(name, mode, &parent, data); | |
623 | if (!p) | |
624 | return NULL; | |
625 | p->proc_fops = &proc_single_fops; | |
626 | p->single_show = show; | |
627 | return proc_register(parent, p); | |
628 | } | |
629 | EXPORT_SYMBOL(proc_create_single_data); | |
630 | ||
271a15ea DH |
631 | void proc_set_size(struct proc_dir_entry *de, loff_t size) |
632 | { | |
633 | de->size = size; | |
634 | } | |
635 | EXPORT_SYMBOL(proc_set_size); | |
636 | ||
637 | void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid) | |
638 | { | |
639 | de->uid = uid; | |
640 | de->gid = gid; | |
641 | } | |
642 | EXPORT_SYMBOL(proc_set_user); | |
2d3a4e36 | 643 | |
135d5655 AD |
644 | void pde_put(struct proc_dir_entry *pde) |
645 | { | |
9cdd83e3 | 646 | if (refcount_dec_and_test(&pde->refcnt)) { |
b4884f23 AD |
647 | proc_free_inum(pde->low_ino); |
648 | pde_free(pde); | |
649 | } | |
135d5655 AD |
650 | } |
651 | ||
8ce584c7 AV |
652 | /* |
653 | * Remove a /proc entry and free it if it's not currently in use. | |
654 | */ | |
655 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
656 | { | |
8ce584c7 AV |
657 | struct proc_dir_entry *de = NULL; |
658 | const char *fn = name; | |
659 | unsigned int len; | |
660 | ||
ecf1a3df | 661 | write_lock(&proc_subdir_lock); |
8ce584c7 | 662 | if (__xlate_proc_name(name, &parent, &fn) != 0) { |
ecf1a3df | 663 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
664 | return; |
665 | } | |
666 | len = strlen(fn); | |
667 | ||
710585d4 ND |
668 | de = pde_subdir_find(parent, fn, len); |
669 | if (de) | |
4f113437 | 670 | rb_erase(&de->subdir_node, &parent->subdir); |
ecf1a3df | 671 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
672 | if (!de) { |
673 | WARN(1, "name '%s'\n", name); | |
674 | return; | |
675 | } | |
676 | ||
866ad9a7 | 677 | proc_entry_rundown(de); |
881adb85 | 678 | |
f649d6d3 AD |
679 | if (S_ISDIR(de->mode)) |
680 | parent->nlink--; | |
681 | de->nlink = 0; | |
710585d4 ND |
682 | WARN(pde_subdir_first(de), |
683 | "%s: removing non-empty directory '%s/%s', leaking at least '%s'\n", | |
684 | __func__, de->parent->name, de->name, pde_subdir_first(de)->name); | |
135d5655 | 685 | pde_put(de); |
1da177e4 | 686 | } |
587d4a17 | 687 | EXPORT_SYMBOL(remove_proc_entry); |
8ce584c7 AV |
688 | |
689 | int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) | |
690 | { | |
8ce584c7 AV |
691 | struct proc_dir_entry *root = NULL, *de, *next; |
692 | const char *fn = name; | |
693 | unsigned int len; | |
694 | ||
ecf1a3df | 695 | write_lock(&proc_subdir_lock); |
8ce584c7 | 696 | if (__xlate_proc_name(name, &parent, &fn) != 0) { |
ecf1a3df | 697 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
698 | return -ENOENT; |
699 | } | |
700 | len = strlen(fn); | |
701 | ||
710585d4 | 702 | root = pde_subdir_find(parent, fn, len); |
8ce584c7 | 703 | if (!root) { |
ecf1a3df | 704 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
705 | return -ENOENT; |
706 | } | |
4f113437 | 707 | rb_erase(&root->subdir_node, &parent->subdir); |
710585d4 | 708 | |
8ce584c7 AV |
709 | de = root; |
710 | while (1) { | |
710585d4 | 711 | next = pde_subdir_first(de); |
8ce584c7 | 712 | if (next) { |
4f113437 | 713 | rb_erase(&next->subdir_node, &de->subdir); |
8ce584c7 AV |
714 | de = next; |
715 | continue; | |
716 | } | |
ecf1a3df | 717 | write_unlock(&proc_subdir_lock); |
8ce584c7 | 718 | |
866ad9a7 | 719 | proc_entry_rundown(de); |
8ce584c7 AV |
720 | next = de->parent; |
721 | if (S_ISDIR(de->mode)) | |
722 | next->nlink--; | |
723 | de->nlink = 0; | |
724 | if (de == root) | |
725 | break; | |
726 | pde_put(de); | |
727 | ||
ecf1a3df | 728 | write_lock(&proc_subdir_lock); |
8ce584c7 AV |
729 | de = next; |
730 | } | |
731 | pde_put(root); | |
732 | return 0; | |
733 | } | |
734 | EXPORT_SYMBOL(remove_proc_subtree); | |
4a520d27 DH |
735 | |
736 | void *proc_get_parent_data(const struct inode *inode) | |
737 | { | |
738 | struct proc_dir_entry *de = PDE(inode); | |
739 | return de->parent->data; | |
740 | } | |
741 | EXPORT_SYMBOL_GPL(proc_get_parent_data); | |
a8ca16ea DH |
742 | |
743 | void proc_remove(struct proc_dir_entry *de) | |
744 | { | |
745 | if (de) | |
746 | remove_proc_subtree(de->name, de->parent); | |
747 | } | |
748 | EXPORT_SYMBOL(proc_remove); | |
c30480b9 DH |
749 | |
750 | void *PDE_DATA(const struct inode *inode) | |
751 | { | |
752 | return __PDE_DATA(inode); | |
753 | } | |
754 | EXPORT_SYMBOL(PDE_DATA); | |
564def71 DH |
755 | |
756 | /* | |
757 | * Pull a user buffer into memory and pass it to the file's write handler if | |
758 | * one is supplied. The ->write() method is permitted to modify the | |
759 | * kernel-side buffer. | |
760 | */ | |
761 | ssize_t proc_simple_write(struct file *f, const char __user *ubuf, size_t size, | |
762 | loff_t *_pos) | |
763 | { | |
764 | struct proc_dir_entry *pde = PDE(file_inode(f)); | |
765 | char *buf; | |
766 | int ret; | |
767 | ||
768 | if (!pde->write) | |
769 | return -EACCES; | |
770 | if (size == 0 || size > PAGE_SIZE - 1) | |
771 | return -EINVAL; | |
772 | buf = memdup_user_nul(ubuf, size); | |
773 | if (IS_ERR(buf)) | |
774 | return PTR_ERR(buf); | |
775 | ret = pde->write(f, buf, size); | |
776 | kfree(buf); | |
777 | return ret == 0 ? size : ret; | |
778 | } |