Commit | Line | Data |
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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); |
e06689bf AD |
141 | if (de) { |
142 | nlink_t nlink = READ_ONCE(de->nlink); | |
143 | if (nlink > 0) { | |
144 | set_nlink(inode, nlink); | |
145 | } | |
146 | } | |
2b579bee MS |
147 | |
148 | generic_fillattr(inode, stat); | |
149 | return 0; | |
150 | } | |
151 | ||
c5ef1c42 | 152 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
153 | .setattr = proc_notify_change, |
154 | }; | |
155 | ||
156 | /* | |
157 | * This function parses a name such as "tty/driver/serial", and | |
158 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
159 | * returns "serial" in residual. | |
160 | */ | |
e17a5765 AD |
161 | static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret, |
162 | const char **residual) | |
1da177e4 LT |
163 | { |
164 | const char *cp = name, *next; | |
165 | struct proc_dir_entry *de; | |
1da177e4 | 166 | |
7cee4e00 AD |
167 | de = *ret; |
168 | if (!de) | |
169 | de = &proc_root; | |
170 | ||
1da177e4 LT |
171 | while (1) { |
172 | next = strchr(cp, '/'); | |
173 | if (!next) | |
174 | break; | |
175 | ||
5f6354ea | 176 | de = pde_subdir_find(de, cp, next - cp); |
12bac0d9 AD |
177 | if (!de) { |
178 | WARN(1, "name '%s'\n", name); | |
e17a5765 | 179 | return -ENOENT; |
12bac0d9 | 180 | } |
5f6354ea | 181 | cp = next + 1; |
1da177e4 LT |
182 | } |
183 | *residual = cp; | |
184 | *ret = de; | |
e17a5765 AD |
185 | return 0; |
186 | } | |
187 | ||
188 | static int xlate_proc_name(const char *name, struct proc_dir_entry **ret, | |
189 | const char **residual) | |
190 | { | |
191 | int rv; | |
192 | ||
ecf1a3df | 193 | read_lock(&proc_subdir_lock); |
e17a5765 | 194 | rv = __xlate_proc_name(name, ret, residual); |
ecf1a3df | 195 | read_unlock(&proc_subdir_lock); |
e17a5765 | 196 | return rv; |
1da177e4 LT |
197 | } |
198 | ||
9a185409 | 199 | static DEFINE_IDA(proc_inum_ida); |
1da177e4 | 200 | |
67935df4 | 201 | #define PROC_DYNAMIC_FIRST 0xF0000000U |
1da177e4 LT |
202 | |
203 | /* | |
204 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
205 | * 0xffffffff, or zero on failure. | |
206 | */ | |
33d6dce6 | 207 | int proc_alloc_inum(unsigned int *inum) |
1da177e4 | 208 | { |
cde1b693 | 209 | int i; |
1da177e4 | 210 | |
cde1b693 HK |
211 | i = ida_simple_get(&proc_inum_ida, 0, UINT_MAX - PROC_DYNAMIC_FIRST + 1, |
212 | GFP_KERNEL); | |
213 | if (i < 0) | |
214 | return i; | |
1da177e4 | 215 | |
cde1b693 | 216 | *inum = PROC_DYNAMIC_FIRST + (unsigned int)i; |
33d6dce6 | 217 | return 0; |
1da177e4 LT |
218 | } |
219 | ||
33d6dce6 | 220 | void proc_free_inum(unsigned int inum) |
1da177e4 | 221 | { |
cde1b693 | 222 | ida_simple_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); |
1da177e4 LT |
223 | } |
224 | ||
1da4d377 AD |
225 | static int proc_misc_d_revalidate(struct dentry *dentry, unsigned int flags) |
226 | { | |
227 | if (flags & LOOKUP_RCU) | |
228 | return -ECHILD; | |
229 | ||
230 | if (atomic_read(&PDE(d_inode(dentry))->in_use) < 0) | |
231 | return 0; /* revalidate */ | |
232 | return 1; | |
233 | } | |
234 | ||
235 | static int proc_misc_d_delete(const struct dentry *dentry) | |
236 | { | |
237 | return atomic_read(&PDE(d_inode(dentry))->in_use) < 0; | |
238 | } | |
239 | ||
240 | static const struct dentry_operations proc_misc_dentry_ops = { | |
241 | .d_revalidate = proc_misc_d_revalidate, | |
242 | .d_delete = proc_misc_d_delete, | |
243 | }; | |
244 | ||
1da177e4 LT |
245 | /* |
246 | * Don't create negative dentries here, return -ENOENT by hand | |
247 | * instead. | |
248 | */ | |
93ad5bc6 AD |
249 | struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry, |
250 | struct proc_dir_entry *de) | |
1da177e4 | 251 | { |
d3d009cb | 252 | struct inode *inode; |
1da177e4 | 253 | |
ecf1a3df | 254 | read_lock(&proc_subdir_lock); |
710585d4 ND |
255 | de = pde_subdir_find(de, dentry->d_name.name, dentry->d_name.len); |
256 | if (de) { | |
257 | pde_get(de); | |
ecf1a3df | 258 | read_unlock(&proc_subdir_lock); |
710585d4 ND |
259 | inode = proc_get_inode(dir->i_sb, de); |
260 | if (!inode) | |
261 | return ERR_PTR(-ENOMEM); | |
1fde6f21 | 262 | d_set_d_op(dentry, de->proc_dops); |
888e2b03 | 263 | return d_splice_alias(inode, dentry); |
1da177e4 | 264 | } |
ecf1a3df | 265 | read_unlock(&proc_subdir_lock); |
d3d009cb | 266 | return ERR_PTR(-ENOENT); |
1da177e4 LT |
267 | } |
268 | ||
e9720acd | 269 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 270 | unsigned int flags) |
e9720acd | 271 | { |
6814ef2d AG |
272 | struct proc_fs_info *fs_info = proc_sb_info(dir->i_sb); |
273 | ||
274 | if (fs_info->pidonly == PROC_PIDONLY_ON) | |
275 | return ERR_PTR(-ENOENT); | |
276 | ||
93ad5bc6 | 277 | return proc_lookup_de(dir, dentry, PDE(dir)); |
e9720acd PE |
278 | } |
279 | ||
1da177e4 LT |
280 | /* |
281 | * This returns non-zero if at EOF, so that the /proc | |
282 | * root directory can use this and check if it should | |
283 | * continue with the <pid> entries.. | |
284 | * | |
285 | * Note that the VFS-layer doesn't care about the return | |
286 | * value of the readdir() call, as long as it's non-negative | |
287 | * for success.. | |
288 | */ | |
93ad5bc6 AD |
289 | int proc_readdir_de(struct file *file, struct dir_context *ctx, |
290 | struct proc_dir_entry *de) | |
1da177e4 | 291 | { |
1da177e4 | 292 | int i; |
f0c3b509 AV |
293 | |
294 | if (!dir_emit_dots(file, ctx)) | |
295 | return 0; | |
296 | ||
8d48b2e0 | 297 | i = ctx->pos - 2; |
ecf1a3df | 298 | read_lock(&proc_subdir_lock); |
710585d4 | 299 | de = pde_subdir_first(de); |
f0c3b509 AV |
300 | for (;;) { |
301 | if (!de) { | |
ecf1a3df | 302 | read_unlock(&proc_subdir_lock); |
f0c3b509 AV |
303 | return 0; |
304 | } | |
305 | if (!i) | |
306 | break; | |
710585d4 | 307 | de = pde_subdir_next(de); |
f0c3b509 | 308 | i--; |
1da177e4 | 309 | } |
f0c3b509 AV |
310 | |
311 | do { | |
312 | struct proc_dir_entry *next; | |
313 | pde_get(de); | |
ecf1a3df | 314 | read_unlock(&proc_subdir_lock); |
f0c3b509 AV |
315 | if (!dir_emit(ctx, de->name, de->namelen, |
316 | de->low_ino, de->mode >> 12)) { | |
317 | pde_put(de); | |
318 | return 0; | |
319 | } | |
f0c3b509 | 320 | ctx->pos++; |
8d48b2e0 | 321 | read_lock(&proc_subdir_lock); |
710585d4 | 322 | next = pde_subdir_next(de); |
f0c3b509 AV |
323 | pde_put(de); |
324 | de = next; | |
325 | } while (de); | |
ecf1a3df | 326 | read_unlock(&proc_subdir_lock); |
fd3930f7 | 327 | return 1; |
1da177e4 LT |
328 | } |
329 | ||
f0c3b509 | 330 | int proc_readdir(struct file *file, struct dir_context *ctx) |
e9720acd | 331 | { |
f0c3b509 | 332 | struct inode *inode = file_inode(file); |
6814ef2d AG |
333 | struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb); |
334 | ||
335 | if (fs_info->pidonly == PROC_PIDONLY_ON) | |
336 | return 1; | |
e9720acd | 337 | |
93ad5bc6 | 338 | return proc_readdir_de(file, ctx, PDE(inode)); |
e9720acd PE |
339 | } |
340 | ||
1da177e4 LT |
341 | /* |
342 | * These are the generic /proc directory operations. They | |
343 | * use the in-memory "struct proc_dir_entry" tree to parse | |
344 | * the /proc directory. | |
345 | */ | |
00977a59 | 346 | static const struct file_operations proc_dir_operations = { |
b4df2b92 | 347 | .llseek = generic_file_llseek, |
1da177e4 | 348 | .read = generic_read_dir, |
f50752ea | 349 | .iterate_shared = proc_readdir, |
1da177e4 LT |
350 | }; |
351 | ||
352 | /* | |
353 | * proc directories can do almost nothing.. | |
354 | */ | |
c5ef1c42 | 355 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 356 | .lookup = proc_lookup, |
2b579bee | 357 | .getattr = proc_getattr, |
1da177e4 LT |
358 | .setattr = proc_notify_change, |
359 | }; | |
360 | ||
61172eae CH |
361 | /* returns the registered entry, or frees dp and returns NULL on failure */ |
362 | struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, | |
363 | struct proc_dir_entry *dp) | |
1da177e4 | 364 | { |
61172eae CH |
365 | if (proc_alloc_inum(&dp->low_ino)) |
366 | goto out_free_entry; | |
64a07bd8 | 367 | |
ecf1a3df | 368 | write_lock(&proc_subdir_lock); |
99fc06df | 369 | dp->parent = dir; |
b208d54b | 370 | if (pde_subdir_insert(dir, dp) == false) { |
710585d4 ND |
371 | WARN(1, "proc_dir_entry '%s/%s' already registered\n", |
372 | dir->name, dp->name); | |
ecf1a3df | 373 | write_unlock(&proc_subdir_lock); |
61172eae | 374 | goto out_free_inum; |
b208d54b | 375 | } |
e06689bf | 376 | dir->nlink++; |
ecf1a3df | 377 | write_unlock(&proc_subdir_lock); |
99fc06df | 378 | |
61172eae CH |
379 | return dp; |
380 | out_free_inum: | |
381 | proc_free_inum(dp->low_ino); | |
382 | out_free_entry: | |
383 | pde_free(dp); | |
384 | return NULL; | |
1da177e4 LT |
385 | } |
386 | ||
2d3a4e36 | 387 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 | 388 | const char *name, |
d161a13f | 389 | umode_t mode, |
1da177e4 LT |
390 | nlink_t nlink) |
391 | { | |
392 | struct proc_dir_entry *ent = NULL; | |
dbcdb504 AD |
393 | const char *fn; |
394 | struct qstr qstr; | |
1da177e4 | 395 | |
7cee4e00 | 396 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 | 397 | goto out; |
dbcdb504 AD |
398 | qstr.name = fn; |
399 | qstr.len = strlen(fn); | |
400 | if (qstr.len == 0 || qstr.len >= 256) { | |
401 | WARN(1, "name len %u\n", qstr.len); | |
402 | return NULL; | |
403 | } | |
b77d70db AD |
404 | if (qstr.len == 1 && fn[0] == '.') { |
405 | WARN(1, "name '.'\n"); | |
406 | return NULL; | |
407 | } | |
408 | if (qstr.len == 2 && fn[0] == '.' && fn[1] == '.') { | |
409 | WARN(1, "name '..'\n"); | |
410 | return NULL; | |
411 | } | |
dbcdb504 AD |
412 | if (*parent == &proc_root && name_to_int(&qstr) != ~0U) { |
413 | WARN(1, "create '/proc/%s' by hand\n", qstr.name); | |
414 | return NULL; | |
415 | } | |
eb6d38d5 EB |
416 | if (is_empty_pde(*parent)) { |
417 | WARN(1, "attempt to add to permanently empty directory"); | |
418 | return NULL; | |
419 | } | |
1da177e4 | 420 | |
b4884f23 | 421 | ent = kmem_cache_zalloc(proc_dir_entry_cache, GFP_KERNEL); |
17baa2a2 | 422 | if (!ent) |
423 | goto out; | |
1da177e4 | 424 | |
24074a35 | 425 | if (qstr.len + 1 <= SIZEOF_PDE_INLINE_NAME) { |
b4884f23 AD |
426 | ent->name = ent->inline_name; |
427 | } else { | |
428 | ent->name = kmalloc(qstr.len + 1, GFP_KERNEL); | |
429 | if (!ent->name) { | |
430 | pde_free(ent); | |
431 | return NULL; | |
432 | } | |
433 | } | |
434 | ||
dbcdb504 AD |
435 | memcpy(ent->name, fn, qstr.len + 1); |
436 | ent->namelen = qstr.len; | |
1da177e4 LT |
437 | ent->mode = mode; |
438 | ent->nlink = nlink; | |
4f113437 | 439 | ent->subdir = RB_ROOT; |
9cdd83e3 | 440 | refcount_set(&ent->refcnt, 1); |
786d7e16 | 441 | spin_lock_init(&ent->pde_unload_lock); |
881adb85 | 442 | INIT_LIST_HEAD(&ent->pde_openers); |
c110486f DT |
443 | proc_set_user(ent, (*parent)->uid, (*parent)->gid); |
444 | ||
1fde6f21 AD |
445 | ent->proc_dops = &proc_misc_dentry_ops; |
446 | ||
17baa2a2 | 447 | out: |
1da177e4 LT |
448 | return ent; |
449 | } | |
450 | ||
451 | struct proc_dir_entry *proc_symlink(const char *name, | |
452 | struct proc_dir_entry *parent, const char *dest) | |
453 | { | |
454 | struct proc_dir_entry *ent; | |
455 | ||
2d3a4e36 | 456 | ent = __proc_create(&parent, name, |
1da177e4 LT |
457 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
458 | ||
459 | if (ent) { | |
460 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
461 | if (ent->data) { | |
462 | strcpy((char*)ent->data,dest); | |
d443b9fd | 463 | ent->proc_iops = &proc_link_inode_operations; |
61172eae | 464 | ent = proc_register(parent, ent); |
1da177e4 | 465 | } else { |
b4884f23 | 466 | pde_free(ent); |
1da177e4 LT |
467 | ent = NULL; |
468 | } | |
469 | } | |
470 | return ent; | |
471 | } | |
587d4a17 | 472 | EXPORT_SYMBOL(proc_symlink); |
1da177e4 | 473 | |
270b5ac2 DH |
474 | struct proc_dir_entry *proc_mkdir_data(const char *name, umode_t mode, |
475 | struct proc_dir_entry *parent, void *data) | |
1da177e4 LT |
476 | { |
477 | struct proc_dir_entry *ent; | |
478 | ||
270b5ac2 DH |
479 | if (mode == 0) |
480 | mode = S_IRUGO | S_IXUGO; | |
481 | ||
2d3a4e36 | 482 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 483 | if (ent) { |
270b5ac2 | 484 | ent->data = data; |
d56c0d45 | 485 | ent->proc_dir_ops = &proc_dir_operations; |
d443b9fd | 486 | ent->proc_iops = &proc_dir_inode_operations; |
61172eae | 487 | ent = proc_register(parent, ent); |
1da177e4 LT |
488 | } |
489 | return ent; | |
490 | } | |
270b5ac2 | 491 | EXPORT_SYMBOL_GPL(proc_mkdir_data); |
1da177e4 | 492 | |
270b5ac2 DH |
493 | struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode, |
494 | struct proc_dir_entry *parent) | |
78e92b99 | 495 | { |
270b5ac2 | 496 | return proc_mkdir_data(name, mode, parent, NULL); |
78e92b99 | 497 | } |
270b5ac2 | 498 | EXPORT_SYMBOL(proc_mkdir_mode); |
78e92b99 | 499 | |
1da177e4 LT |
500 | struct proc_dir_entry *proc_mkdir(const char *name, |
501 | struct proc_dir_entry *parent) | |
502 | { | |
270b5ac2 | 503 | return proc_mkdir_data(name, 0, parent, NULL); |
1da177e4 | 504 | } |
587d4a17 | 505 | EXPORT_SYMBOL(proc_mkdir); |
1da177e4 | 506 | |
eb6d38d5 EB |
507 | struct proc_dir_entry *proc_create_mount_point(const char *name) |
508 | { | |
509 | umode_t mode = S_IFDIR | S_IRUGO | S_IXUGO; | |
510 | struct proc_dir_entry *ent, *parent = NULL; | |
511 | ||
512 | ent = __proc_create(&parent, name, mode, 2); | |
513 | if (ent) { | |
514 | ent->data = NULL; | |
d56c0d45 | 515 | ent->proc_dir_ops = NULL; |
eb6d38d5 | 516 | ent->proc_iops = NULL; |
61172eae | 517 | ent = proc_register(parent, ent); |
eb6d38d5 EB |
518 | } |
519 | return ent; | |
520 | } | |
f97df70b | 521 | EXPORT_SYMBOL(proc_create_mount_point); |
eb6d38d5 | 522 | |
7aed53d1 CH |
523 | struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode, |
524 | struct proc_dir_entry **parent, void *data) | |
2d3a4e36 | 525 | { |
7aed53d1 CH |
526 | struct proc_dir_entry *p; |
527 | ||
b6cdc731 AV |
528 | if ((mode & S_IFMT) == 0) |
529 | mode |= S_IFREG; | |
7aed53d1 CH |
530 | if ((mode & S_IALLUGO) == 0) |
531 | mode |= S_IRUGO; | |
532 | if (WARN_ON_ONCE(!S_ISREG(mode))) | |
b6cdc731 | 533 | return NULL; |
7aed53d1 CH |
534 | |
535 | p = __proc_create(parent, name, mode, 1); | |
536 | if (p) { | |
537 | p->proc_iops = &proc_file_inode_operations; | |
538 | p->data = data; | |
2d3a4e36 | 539 | } |
7aed53d1 CH |
540 | return p; |
541 | } | |
542 | ||
d919b33d AD |
543 | static inline void pde_set_flags(struct proc_dir_entry *pde) |
544 | { | |
545 | if (pde->proc_ops->proc_flags & PROC_ENTRY_PERMANENT) | |
546 | pde->flags |= PROC_ENTRY_PERMANENT; | |
547 | } | |
548 | ||
7aed53d1 CH |
549 | struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, |
550 | struct proc_dir_entry *parent, | |
d56c0d45 | 551 | const struct proc_ops *proc_ops, void *data) |
7aed53d1 CH |
552 | { |
553 | struct proc_dir_entry *p; | |
2d3a4e36 | 554 | |
7aed53d1 CH |
555 | p = proc_create_reg(name, mode, &parent, data); |
556 | if (!p) | |
557 | return NULL; | |
d56c0d45 | 558 | p->proc_ops = proc_ops; |
d919b33d | 559 | pde_set_flags(p); |
7aed53d1 | 560 | return proc_register(parent, p); |
2d3a4e36 | 561 | } |
587d4a17 | 562 | EXPORT_SYMBOL(proc_create_data); |
271a15ea | 563 | |
855d9765 AD |
564 | struct proc_dir_entry *proc_create(const char *name, umode_t mode, |
565 | struct proc_dir_entry *parent, | |
d56c0d45 | 566 | const struct proc_ops *proc_ops) |
855d9765 | 567 | { |
d56c0d45 | 568 | return proc_create_data(name, mode, parent, proc_ops, NULL); |
855d9765 AD |
569 | } |
570 | EXPORT_SYMBOL(proc_create); | |
571 | ||
fddda2b7 CH |
572 | static int proc_seq_open(struct inode *inode, struct file *file) |
573 | { | |
574 | struct proc_dir_entry *de = PDE(inode); | |
575 | ||
44414d82 CH |
576 | if (de->state_size) |
577 | return seq_open_private(file, de->seq_ops, de->state_size); | |
fddda2b7 CH |
578 | return seq_open(file, de->seq_ops); |
579 | } | |
580 | ||
877f919e CH |
581 | static int proc_seq_release(struct inode *inode, struct file *file) |
582 | { | |
583 | struct proc_dir_entry *de = PDE(inode); | |
584 | ||
585 | if (de->state_size) | |
586 | return seq_release_private(inode, file); | |
587 | return seq_release(inode, file); | |
588 | } | |
589 | ||
d56c0d45 | 590 | static const struct proc_ops proc_seq_ops = { |
d919b33d | 591 | /* not permanent -- can call into arbitrary seq_operations */ |
d56c0d45 | 592 | .proc_open = proc_seq_open, |
b24c30c6 | 593 | .proc_read_iter = seq_read_iter, |
d56c0d45 AD |
594 | .proc_lseek = seq_lseek, |
595 | .proc_release = proc_seq_release, | |
fddda2b7 CH |
596 | }; |
597 | ||
44414d82 | 598 | struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode, |
fddda2b7 | 599 | struct proc_dir_entry *parent, const struct seq_operations *ops, |
44414d82 | 600 | unsigned int state_size, void *data) |
fddda2b7 CH |
601 | { |
602 | struct proc_dir_entry *p; | |
603 | ||
604 | p = proc_create_reg(name, mode, &parent, data); | |
605 | if (!p) | |
606 | return NULL; | |
d56c0d45 | 607 | p->proc_ops = &proc_seq_ops; |
fddda2b7 | 608 | p->seq_ops = ops; |
44414d82 | 609 | p->state_size = state_size; |
fddda2b7 CH |
610 | return proc_register(parent, p); |
611 | } | |
44414d82 | 612 | EXPORT_SYMBOL(proc_create_seq_private); |
fddda2b7 | 613 | |
3f3942ac CH |
614 | static int proc_single_open(struct inode *inode, struct file *file) |
615 | { | |
616 | struct proc_dir_entry *de = PDE(inode); | |
617 | ||
618 | return single_open(file, de->single_show, de->data); | |
619 | } | |
620 | ||
d56c0d45 | 621 | static const struct proc_ops proc_single_ops = { |
d919b33d | 622 | /* not permanent -- can call into arbitrary ->single_show */ |
d56c0d45 | 623 | .proc_open = proc_single_open, |
7cfc630e | 624 | .proc_read_iter = seq_read_iter, |
d56c0d45 AD |
625 | .proc_lseek = seq_lseek, |
626 | .proc_release = single_release, | |
3f3942ac CH |
627 | }; |
628 | ||
629 | struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode, | |
630 | struct proc_dir_entry *parent, | |
631 | int (*show)(struct seq_file *, void *), void *data) | |
632 | { | |
633 | struct proc_dir_entry *p; | |
634 | ||
635 | p = proc_create_reg(name, mode, &parent, data); | |
636 | if (!p) | |
637 | return NULL; | |
d56c0d45 | 638 | p->proc_ops = &proc_single_ops; |
3f3942ac CH |
639 | p->single_show = show; |
640 | return proc_register(parent, p); | |
641 | } | |
642 | EXPORT_SYMBOL(proc_create_single_data); | |
643 | ||
271a15ea DH |
644 | void proc_set_size(struct proc_dir_entry *de, loff_t size) |
645 | { | |
646 | de->size = size; | |
647 | } | |
648 | EXPORT_SYMBOL(proc_set_size); | |
649 | ||
650 | void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid) | |
651 | { | |
652 | de->uid = uid; | |
653 | de->gid = gid; | |
654 | } | |
655 | EXPORT_SYMBOL(proc_set_user); | |
2d3a4e36 | 656 | |
135d5655 AD |
657 | void pde_put(struct proc_dir_entry *pde) |
658 | { | |
9cdd83e3 | 659 | if (refcount_dec_and_test(&pde->refcnt)) { |
b4884f23 AD |
660 | proc_free_inum(pde->low_ino); |
661 | pde_free(pde); | |
662 | } | |
135d5655 AD |
663 | } |
664 | ||
8ce584c7 AV |
665 | /* |
666 | * Remove a /proc entry and free it if it's not currently in use. | |
667 | */ | |
668 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
669 | { | |
8ce584c7 AV |
670 | struct proc_dir_entry *de = NULL; |
671 | const char *fn = name; | |
672 | unsigned int len; | |
673 | ||
ecf1a3df | 674 | write_lock(&proc_subdir_lock); |
8ce584c7 | 675 | if (__xlate_proc_name(name, &parent, &fn) != 0) { |
ecf1a3df | 676 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
677 | return; |
678 | } | |
679 | len = strlen(fn); | |
680 | ||
710585d4 | 681 | de = pde_subdir_find(parent, fn, len); |
e06689bf | 682 | if (de) { |
d919b33d AD |
683 | if (unlikely(pde_is_permanent(de))) { |
684 | WARN(1, "removing permanent /proc entry '%s'", de->name); | |
685 | de = NULL; | |
686 | } else { | |
687 | rb_erase(&de->subdir_node, &parent->subdir); | |
688 | if (S_ISDIR(de->mode)) | |
689 | parent->nlink--; | |
e06689bf AD |
690 | } |
691 | } | |
ecf1a3df | 692 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
693 | if (!de) { |
694 | WARN(1, "name '%s'\n", name); | |
695 | return; | |
696 | } | |
697 | ||
866ad9a7 | 698 | proc_entry_rundown(de); |
881adb85 | 699 | |
710585d4 ND |
700 | WARN(pde_subdir_first(de), |
701 | "%s: removing non-empty directory '%s/%s', leaking at least '%s'\n", | |
702 | __func__, de->parent->name, de->name, pde_subdir_first(de)->name); | |
135d5655 | 703 | pde_put(de); |
1da177e4 | 704 | } |
587d4a17 | 705 | EXPORT_SYMBOL(remove_proc_entry); |
8ce584c7 AV |
706 | |
707 | int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) | |
708 | { | |
8ce584c7 AV |
709 | struct proc_dir_entry *root = NULL, *de, *next; |
710 | const char *fn = name; | |
711 | unsigned int len; | |
712 | ||
ecf1a3df | 713 | write_lock(&proc_subdir_lock); |
8ce584c7 | 714 | if (__xlate_proc_name(name, &parent, &fn) != 0) { |
ecf1a3df | 715 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
716 | return -ENOENT; |
717 | } | |
718 | len = strlen(fn); | |
719 | ||
710585d4 | 720 | root = pde_subdir_find(parent, fn, len); |
8ce584c7 | 721 | if (!root) { |
ecf1a3df | 722 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
723 | return -ENOENT; |
724 | } | |
d919b33d AD |
725 | if (unlikely(pde_is_permanent(root))) { |
726 | write_unlock(&proc_subdir_lock); | |
727 | WARN(1, "removing permanent /proc entry '%s/%s'", | |
728 | root->parent->name, root->name); | |
729 | return -EINVAL; | |
730 | } | |
4f113437 | 731 | rb_erase(&root->subdir_node, &parent->subdir); |
710585d4 | 732 | |
8ce584c7 AV |
733 | de = root; |
734 | while (1) { | |
710585d4 | 735 | next = pde_subdir_first(de); |
8ce584c7 | 736 | if (next) { |
d919b33d AD |
737 | if (unlikely(pde_is_permanent(root))) { |
738 | write_unlock(&proc_subdir_lock); | |
739 | WARN(1, "removing permanent /proc entry '%s/%s'", | |
740 | next->parent->name, next->name); | |
741 | return -EINVAL; | |
742 | } | |
4f113437 | 743 | rb_erase(&next->subdir_node, &de->subdir); |
8ce584c7 AV |
744 | de = next; |
745 | continue; | |
746 | } | |
8ce584c7 AV |
747 | next = de->parent; |
748 | if (S_ISDIR(de->mode)) | |
749 | next->nlink--; | |
e06689bf AD |
750 | write_unlock(&proc_subdir_lock); |
751 | ||
752 | proc_entry_rundown(de); | |
8ce584c7 AV |
753 | if (de == root) |
754 | break; | |
755 | pde_put(de); | |
756 | ||
ecf1a3df | 757 | write_lock(&proc_subdir_lock); |
8ce584c7 AV |
758 | de = next; |
759 | } | |
760 | pde_put(root); | |
761 | return 0; | |
762 | } | |
763 | EXPORT_SYMBOL(remove_proc_subtree); | |
4a520d27 DH |
764 | |
765 | void *proc_get_parent_data(const struct inode *inode) | |
766 | { | |
767 | struct proc_dir_entry *de = PDE(inode); | |
768 | return de->parent->data; | |
769 | } | |
770 | EXPORT_SYMBOL_GPL(proc_get_parent_data); | |
a8ca16ea DH |
771 | |
772 | void proc_remove(struct proc_dir_entry *de) | |
773 | { | |
774 | if (de) | |
775 | remove_proc_subtree(de->name, de->parent); | |
776 | } | |
777 | EXPORT_SYMBOL(proc_remove); | |
c30480b9 DH |
778 | |
779 | void *PDE_DATA(const struct inode *inode) | |
780 | { | |
781 | return __PDE_DATA(inode); | |
782 | } | |
783 | EXPORT_SYMBOL(PDE_DATA); | |
564def71 DH |
784 | |
785 | /* | |
786 | * Pull a user buffer into memory and pass it to the file's write handler if | |
787 | * one is supplied. The ->write() method is permitted to modify the | |
788 | * kernel-side buffer. | |
789 | */ | |
790 | ssize_t proc_simple_write(struct file *f, const char __user *ubuf, size_t size, | |
791 | loff_t *_pos) | |
792 | { | |
793 | struct proc_dir_entry *pde = PDE(file_inode(f)); | |
794 | char *buf; | |
795 | int ret; | |
796 | ||
797 | if (!pde->write) | |
798 | return -EACCES; | |
799 | if (size == 0 || size > PAGE_SIZE - 1) | |
800 | return -EINVAL; | |
801 | buf = memdup_user_nul(ubuf, size); | |
802 | if (IS_ERR(buf)) | |
803 | return PTR_ERR(buf); | |
804 | ret = pde->write(f, buf, size); | |
805 | kfree(buf); | |
806 | return ret == 0 ? size : ret; | |
807 | } |