Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
6d66f5cd TH |
2 | * fs/sysfs/dir.c - sysfs core and dir operation implementation |
3 | * | |
4 | * Copyright (c) 2001-3 Patrick Mochel | |
5 | * Copyright (c) 2007 SUSE Linux Products GmbH | |
6 | * Copyright (c) 2007 Tejun Heo <teheo@suse.de> | |
7 | * | |
8 | * This file is released under the GPLv2. | |
9 | * | |
10 | * Please see Documentation/filesystems/sysfs.txt for more information. | |
1da177e4 LT |
11 | */ |
12 | ||
13 | #undef DEBUG | |
14 | ||
15 | #include <linux/fs.h> | |
16 | #include <linux/mount.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/kobject.h> | |
5f45f1a7 | 19 | #include <linux/namei.h> |
2b611bb7 | 20 | #include <linux/idr.h> |
8619f979 | 21 | #include <linux/completion.h> |
869512ab | 22 | #include <linux/mutex.h> |
c6f87733 | 23 | #include <linux/slab.h> |
4c3da220 | 24 | #include <linux/security.h> |
4e4d6d86 | 25 | #include <linux/hash.h> |
1da177e4 LT |
26 | #include "sysfs.h" |
27 | ||
3007e997 | 28 | DEFINE_MUTEX(sysfs_mutex); |
f7a75f0a | 29 | DEFINE_SPINLOCK(sysfs_assoc_lock); |
1da177e4 | 30 | |
4e4d6d86 EB |
31 | #define to_sysfs_dirent(X) rb_entry((X), struct sysfs_dirent, s_rb); |
32 | ||
f7a75f0a | 33 | static DEFINE_SPINLOCK(sysfs_ino_lock); |
2b611bb7 TH |
34 | static DEFINE_IDA(sysfs_ino_ida); |
35 | ||
0c73f18b | 36 | /** |
4e4d6d86 EB |
37 | * sysfs_name_hash |
38 | * @ns: Namespace tag to hash | |
39 | * @name: Null terminated string to hash | |
40 | * | |
41 | * Returns 31 bit hash of ns + name (so it fits in an off_t ) | |
42 | */ | |
43 | static unsigned int sysfs_name_hash(const void *ns, const char *name) | |
44 | { | |
45 | unsigned long hash = init_name_hash(); | |
46 | unsigned int len = strlen(name); | |
47 | while (len--) | |
48 | hash = partial_name_hash(*name++, hash); | |
49 | hash = ( end_name_hash(hash) ^ hash_ptr( (void *)ns, 31 ) ); | |
50 | hash &= 0x7fffffffU; | |
51 | /* Reserve hash numbers 0, 1 and INT_MAX for magic directory entries */ | |
52 | if (hash < 1) | |
53 | hash += 2; | |
54 | if (hash >= INT_MAX) | |
55 | hash = INT_MAX - 1; | |
56 | return hash; | |
57 | } | |
58 | ||
59 | static int sysfs_name_compare(unsigned int hash, const void *ns, | |
60 | const char *name, const struct sysfs_dirent *sd) | |
61 | { | |
62 | if (hash != sd->s_hash) | |
63 | return hash - sd->s_hash; | |
64 | if (ns != sd->s_ns) | |
65 | return ns - sd->s_ns; | |
66 | return strcmp(name, sd->s_name); | |
67 | } | |
68 | ||
69 | static int sysfs_sd_compare(const struct sysfs_dirent *left, | |
70 | const struct sysfs_dirent *right) | |
71 | { | |
72 | return sysfs_name_compare(left->s_hash, left->s_ns, left->s_name, | |
73 | right); | |
74 | } | |
75 | ||
76 | /** | |
43474910 | 77 | * sysfs_link_sibling - link sysfs_dirent into sibling rbtree |
0c73f18b TH |
78 | * @sd: sysfs_dirent of interest |
79 | * | |
4e4d6d86 | 80 | * Link @sd into its sibling rbtree which starts from |
bc747f37 | 81 | * sd->s_parent->s_dir.children. |
0c73f18b TH |
82 | * |
83 | * Locking: | |
3007e997 | 84 | * mutex_lock(sysfs_mutex) |
4e4d6d86 EB |
85 | * |
86 | * RETURNS: | |
87 | * 0 on susccess -EEXIST on failure. | |
0c73f18b | 88 | */ |
4e4d6d86 | 89 | static int sysfs_link_sibling(struct sysfs_dirent *sd) |
0c73f18b | 90 | { |
4e4d6d86 EB |
91 | struct rb_node **node = &sd->s_parent->s_dir.children.rb_node; |
92 | struct rb_node *parent = NULL; | |
4f72c0ca | 93 | |
54d20f00 GKH |
94 | if (sysfs_type(sd) == SYSFS_DIR) |
95 | sd->s_parent->s_dir.subdirs++; | |
96 | ||
4e4d6d86 EB |
97 | while (*node) { |
98 | struct sysfs_dirent *pos; | |
99 | int result; | |
100 | ||
101 | pos = to_sysfs_dirent(*node); | |
102 | parent = *node; | |
103 | result = sysfs_sd_compare(sd, pos); | |
104 | if (result < 0) | |
105 | node = &pos->s_rb.rb_left; | |
106 | else if (result > 0) | |
107 | node = &pos->s_rb.rb_right; | |
108 | else | |
109 | return -EEXIST; | |
4f72c0ca | 110 | } |
4e4d6d86 EB |
111 | /* add new node and rebalance the tree */ |
112 | rb_link_node(&sd->s_rb, parent, node); | |
113 | rb_insert_color(&sd->s_rb, &sd->s_parent->s_dir.children); | |
114 | return 0; | |
0c73f18b TH |
115 | } |
116 | ||
117 | /** | |
4e4d6d86 | 118 | * sysfs_unlink_sibling - unlink sysfs_dirent from sibling rbtree |
0c73f18b TH |
119 | * @sd: sysfs_dirent of interest |
120 | * | |
4e4d6d86 | 121 | * Unlink @sd from its sibling rbtree which starts from |
bc747f37 | 122 | * sd->s_parent->s_dir.children. |
0c73f18b TH |
123 | * |
124 | * Locking: | |
3007e997 | 125 | * mutex_lock(sysfs_mutex) |
0c73f18b | 126 | */ |
41fc1c27 | 127 | static void sysfs_unlink_sibling(struct sysfs_dirent *sd) |
0c73f18b | 128 | { |
54d20f00 GKH |
129 | if (sysfs_type(sd) == SYSFS_DIR) |
130 | sd->s_parent->s_dir.subdirs--; | |
131 | ||
4e4d6d86 | 132 | rb_erase(&sd->s_rb, &sd->s_parent->s_dir.children); |
0c73f18b TH |
133 | } |
134 | ||
356c05d5 AS |
135 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
136 | ||
137 | /* Test for attributes that want to ignore lockdep for read-locking */ | |
138 | static bool ignore_lockdep(struct sysfs_dirent *sd) | |
139 | { | |
140 | return sysfs_type(sd) == SYSFS_KOBJ_ATTR && | |
141 | sd->s_attr.attr->ignore_lockdep; | |
142 | } | |
143 | ||
144 | #else | |
145 | ||
146 | static inline bool ignore_lockdep(struct sysfs_dirent *sd) | |
147 | { | |
148 | return true; | |
149 | } | |
150 | ||
151 | #endif | |
152 | ||
b6b4a439 TH |
153 | /** |
154 | * sysfs_get_active - get an active reference to sysfs_dirent | |
155 | * @sd: sysfs_dirent to get an active reference to | |
156 | * | |
157 | * Get an active reference of @sd. This function is noop if @sd | |
158 | * is NULL. | |
159 | * | |
160 | * RETURNS: | |
161 | * Pointer to @sd on success, NULL on failure. | |
162 | */ | |
e72ceb8c | 163 | struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) |
b6b4a439 | 164 | { |
8619f979 TH |
165 | if (unlikely(!sd)) |
166 | return NULL; | |
167 | ||
3db3c625 ML |
168 | if (!atomic_inc_unless_negative(&sd->s_active)) |
169 | return NULL; | |
356c05d5 AS |
170 | |
171 | if (likely(!ignore_lockdep(sd))) | |
172 | rwsem_acquire_read(&sd->dep_map, 0, 1, _RET_IP_); | |
173 | return sd; | |
b6b4a439 TH |
174 | } |
175 | ||
176 | /** | |
177 | * sysfs_put_active - put an active reference to sysfs_dirent | |
178 | * @sd: sysfs_dirent to put an active reference to | |
179 | * | |
180 | * Put an active reference to @sd. This function is noop if @sd | |
181 | * is NULL. | |
182 | */ | |
e72ceb8c | 183 | void sysfs_put_active(struct sysfs_dirent *sd) |
b6b4a439 | 184 | { |
8619f979 TH |
185 | int v; |
186 | ||
187 | if (unlikely(!sd)) | |
188 | return; | |
189 | ||
356c05d5 AS |
190 | if (likely(!ignore_lockdep(sd))) |
191 | rwsem_release(&sd->dep_map, 1, _RET_IP_); | |
8619f979 TH |
192 | v = atomic_dec_return(&sd->s_active); |
193 | if (likely(v != SD_DEACTIVATED_BIAS)) | |
194 | return; | |
195 | ||
196 | /* atomic_dec_return() is a mb(), we'll always see the updated | |
58f2a4c7 | 197 | * sd->u.completion. |
8619f979 | 198 | */ |
58f2a4c7 | 199 | complete(sd->u.completion); |
b6b4a439 TH |
200 | } |
201 | ||
b6b4a439 TH |
202 | /** |
203 | * sysfs_deactivate - deactivate sysfs_dirent | |
204 | * @sd: sysfs_dirent to deactivate | |
205 | * | |
8619f979 | 206 | * Deny new active references and drain existing ones. |
b6b4a439 | 207 | */ |
fb6896da | 208 | static void sysfs_deactivate(struct sysfs_dirent *sd) |
b6b4a439 | 209 | { |
8619f979 TH |
210 | DECLARE_COMPLETION_ONSTACK(wait); |
211 | int v; | |
b6b4a439 | 212 | |
58f2a4c7 | 213 | BUG_ON(!(sd->s_flags & SYSFS_FLAG_REMOVED)); |
a2db6842 EB |
214 | |
215 | if (!(sysfs_type(sd) & SYSFS_ACTIVE_REF)) | |
216 | return; | |
217 | ||
58f2a4c7 | 218 | sd->u.completion = (void *)&wait; |
8619f979 | 219 | |
846f9974 | 220 | rwsem_acquire(&sd->dep_map, 0, 0, _RET_IP_); |
8619f979 | 221 | /* atomic_add_return() is a mb(), put_active() will always see |
58f2a4c7 | 222 | * the updated sd->u.completion. |
b6b4a439 | 223 | */ |
8619f979 TH |
224 | v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); |
225 | ||
846f9974 EB |
226 | if (v != SD_DEACTIVATED_BIAS) { |
227 | lock_contended(&sd->dep_map, _RET_IP_); | |
8619f979 | 228 | wait_for_completion(&wait); |
846f9974 | 229 | } |
8619f979 | 230 | |
846f9974 EB |
231 | lock_acquired(&sd->dep_map, _RET_IP_); |
232 | rwsem_release(&sd->dep_map, 1, _RET_IP_); | |
b6b4a439 TH |
233 | } |
234 | ||
cafa6b5d | 235 | static int sysfs_alloc_ino(unsigned int *pino) |
2b611bb7 TH |
236 | { |
237 | int ino, rc; | |
238 | ||
239 | retry: | |
240 | spin_lock(&sysfs_ino_lock); | |
241 | rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); | |
242 | spin_unlock(&sysfs_ino_lock); | |
243 | ||
244 | if (rc == -EAGAIN) { | |
245 | if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) | |
246 | goto retry; | |
247 | rc = -ENOMEM; | |
248 | } | |
249 | ||
250 | *pino = ino; | |
251 | return rc; | |
252 | } | |
253 | ||
cafa6b5d | 254 | static void sysfs_free_ino(unsigned int ino) |
2b611bb7 TH |
255 | { |
256 | spin_lock(&sysfs_ino_lock); | |
257 | ida_remove(&sysfs_ino_ida, ino); | |
258 | spin_unlock(&sysfs_ino_lock); | |
259 | } | |
260 | ||
fa7f912a TH |
261 | void release_sysfs_dirent(struct sysfs_dirent * sd) |
262 | { | |
13b3086d TH |
263 | struct sysfs_dirent *parent_sd; |
264 | ||
265 | repeat: | |
3007e997 TH |
266 | /* Moving/renaming is always done while holding reference. |
267 | * sd->s_parent won't change beneath us. | |
268 | */ | |
13b3086d TH |
269 | parent_sd = sd->s_parent; |
270 | ||
bb2b0051 ML |
271 | WARN(!(sd->s_flags & SYSFS_FLAG_REMOVED), |
272 | "sysfs: free using entry: %s/%s\n", | |
273 | parent_sd ? parent_sd->s_name : "", sd->s_name); | |
274 | ||
b402d72c | 275 | if (sysfs_type(sd) == SYSFS_KOBJ_LINK) |
b1fc3d61 | 276 | sysfs_put(sd->s_symlink.target_sd); |
b402d72c | 277 | if (sysfs_type(sd) & SYSFS_COPY_NAME) |
0c096b50 | 278 | kfree(sd->s_name); |
4c3da220 EB |
279 | if (sd->s_iattr && sd->s_iattr->ia_secdata) |
280 | security_release_secctx(sd->s_iattr->ia_secdata, | |
281 | sd->s_iattr->ia_secdata_len); | |
fa7f912a | 282 | kfree(sd->s_iattr); |
2b611bb7 | 283 | sysfs_free_ino(sd->s_ino); |
fa7f912a | 284 | kmem_cache_free(sysfs_dir_cachep, sd); |
13b3086d TH |
285 | |
286 | sd = parent_sd; | |
287 | if (sd && atomic_dec_and_test(&sd->s_count)) | |
288 | goto repeat; | |
fa7f912a TH |
289 | } |
290 | ||
fe15ce44 | 291 | static int sysfs_dentry_delete(const struct dentry *dentry) |
e8f077c8 EB |
292 | { |
293 | struct sysfs_dirent *sd = dentry->d_fsdata; | |
469796d1 | 294 | return !(sd && !(sd->s_flags & SYSFS_FLAG_REMOVED)); |
e8f077c8 EB |
295 | } |
296 | ||
0b728e19 | 297 | static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags) |
e8f077c8 | 298 | { |
34286d66 | 299 | struct sysfs_dirent *sd; |
e8f077c8 | 300 | int is_dir; |
e5bcac61 | 301 | int type; |
e8f077c8 | 302 | |
0b728e19 | 303 | if (flags & LOOKUP_RCU) |
34286d66 NP |
304 | return -ECHILD; |
305 | ||
306 | sd = dentry->d_fsdata; | |
e8f077c8 EB |
307 | mutex_lock(&sysfs_mutex); |
308 | ||
309 | /* The sysfs dirent has been deleted */ | |
310 | if (sd->s_flags & SYSFS_FLAG_REMOVED) | |
311 | goto out_bad; | |
312 | ||
832b6af1 EB |
313 | /* The sysfs dirent has been moved? */ |
314 | if (dentry->d_parent->d_fsdata != sd->s_parent) | |
315 | goto out_bad; | |
316 | ||
317 | /* The sysfs dirent has been renamed */ | |
318 | if (strcmp(dentry->d_name.name, sd->s_name) != 0) | |
319 | goto out_bad; | |
320 | ||
e5bcac61 GC |
321 | /* The sysfs dirent has been moved to a different namespace */ |
322 | type = KOBJ_NS_TYPE_NONE; | |
17f79be9 | 323 | if (sd->s_parent) { |
e5bcac61 | 324 | type = sysfs_ns_type(sd->s_parent); |
17f79be9 AM |
325 | if (type != KOBJ_NS_TYPE_NONE && |
326 | sysfs_info(dentry->d_sb)->ns[type] != sd->s_ns) | |
327 | goto out_bad; | |
328 | } | |
e5bcac61 | 329 | |
e8f077c8 EB |
330 | mutex_unlock(&sysfs_mutex); |
331 | out_valid: | |
332 | return 1; | |
333 | out_bad: | |
334 | /* Remove the dentry from the dcache hashes. | |
335 | * If this is a deleted dentry we use d_drop instead of d_delete | |
336 | * so sysfs doesn't need to cope with negative dentries. | |
832b6af1 EB |
337 | * |
338 | * If this is a dentry that has simply been renamed we | |
339 | * use d_drop to remove it from the dcache lookup on its | |
340 | * old parent. If this dentry persists later when a lookup | |
341 | * is performed at its new name the dentry will be readded | |
342 | * to the dcache hashes. | |
e8f077c8 EB |
343 | */ |
344 | is_dir = (sysfs_type(sd) == SYSFS_DIR); | |
345 | mutex_unlock(&sysfs_mutex); | |
346 | if (is_dir) { | |
347 | /* If we have submounts we must allow the vfs caches | |
348 | * to lie about the state of the filesystem to prevent | |
349 | * leaks and other nasty things. | |
350 | */ | |
351 | if (have_submounts(dentry)) | |
352 | goto out_valid; | |
353 | shrink_dcache_parent(dentry); | |
354 | } | |
355 | d_drop(dentry); | |
356 | return 0; | |
357 | } | |
358 | ||
469796d1 | 359 | static void sysfs_dentry_release(struct dentry *dentry) |
1da177e4 | 360 | { |
469796d1 | 361 | sysfs_put(dentry->d_fsdata); |
1da177e4 LT |
362 | } |
363 | ||
469796d1 | 364 | const struct dentry_operations sysfs_dentry_ops = { |
e8f077c8 EB |
365 | .d_revalidate = sysfs_dentry_revalidate, |
366 | .d_delete = sysfs_dentry_delete, | |
469796d1 | 367 | .d_release = sysfs_dentry_release, |
1da177e4 LT |
368 | }; |
369 | ||
3e519038 | 370 | struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type) |
1da177e4 | 371 | { |
0c096b50 | 372 | char *dup_name = NULL; |
01da2425 | 373 | struct sysfs_dirent *sd; |
0c096b50 TH |
374 | |
375 | if (type & SYSFS_COPY_NAME) { | |
376 | name = dup_name = kstrdup(name, GFP_KERNEL); | |
377 | if (!name) | |
01da2425 | 378 | return NULL; |
0c096b50 | 379 | } |
1da177e4 | 380 | |
c3762229 | 381 | sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); |
1da177e4 | 382 | if (!sd) |
01da2425 | 383 | goto err_out1; |
1da177e4 | 384 | |
0c096b50 | 385 | if (sysfs_alloc_ino(&sd->s_ino)) |
01da2425 | 386 | goto err_out2; |
2b611bb7 | 387 | |
1da177e4 | 388 | atomic_set(&sd->s_count, 1); |
8619f979 | 389 | atomic_set(&sd->s_active, 0); |
a26cd722 | 390 | |
0c096b50 | 391 | sd->s_name = name; |
a26cd722 | 392 | sd->s_mode = mode; |
bb2b0051 | 393 | sd->s_flags = type | SYSFS_FLAG_REMOVED; |
1da177e4 LT |
394 | |
395 | return sd; | |
0c096b50 | 396 | |
01da2425 | 397 | err_out2: |
0c096b50 | 398 | kmem_cache_free(sysfs_dir_cachep, sd); |
01da2425 AM |
399 | err_out1: |
400 | kfree(dup_name); | |
0c096b50 | 401 | return NULL; |
1da177e4 LT |
402 | } |
403 | ||
3007e997 | 404 | /** |
fb6896da TH |
405 | * sysfs_addrm_start - prepare for sysfs_dirent add/remove |
406 | * @acxt: pointer to sysfs_addrm_cxt to be used | |
407 | * @parent_sd: parent sysfs_dirent | |
3007e997 | 408 | * |
fb6896da TH |
409 | * This function is called when the caller is about to add or |
410 | * remove sysfs_dirent under @parent_sd. This function acquires | |
a16bbc34 | 411 | * sysfs_mutex. @acxt is used to keep and pass context to |
fb6896da | 412 | * other addrm functions. |
3007e997 TH |
413 | * |
414 | * LOCKING: | |
fb6896da | 415 | * Kernel thread context (may sleep). sysfs_mutex is locked on |
a16bbc34 | 416 | * return. |
3007e997 | 417 | */ |
fb6896da TH |
418 | void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, |
419 | struct sysfs_dirent *parent_sd) | |
b592fcfe | 420 | { |
fb6896da TH |
421 | memset(acxt, 0, sizeof(*acxt)); |
422 | acxt->parent_sd = parent_sd; | |
423 | ||
fb6896da | 424 | mutex_lock(&sysfs_mutex); |
fb6896da TH |
425 | } |
426 | ||
427 | /** | |
36ce6dad | 428 | * __sysfs_add_one - add sysfs_dirent to parent without warning |
fb6896da TH |
429 | * @acxt: addrm context to use |
430 | * @sd: sysfs_dirent to be added | |
431 | * | |
432 | * Get @acxt->parent_sd and set sd->s_parent to it and increment | |
181b2e4b TH |
433 | * nlink of parent inode if @sd is a directory and link into the |
434 | * children list of the parent. | |
fb6896da TH |
435 | * |
436 | * This function should be called between calls to | |
437 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be | |
438 | * passed the same @acxt as passed to sysfs_addrm_start(). | |
439 | * | |
440 | * LOCKING: | |
441 | * Determined by sysfs_addrm_start(). | |
23dc2799 TH |
442 | * |
443 | * RETURNS: | |
444 | * 0 on success, -EEXIST if entry with the given name already | |
445 | * exists. | |
fb6896da | 446 | */ |
36ce6dad | 447 | int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
fb6896da | 448 | { |
6b0bfe93 | 449 | struct sysfs_inode_attrs *ps_iattr; |
4e4d6d86 | 450 | int ret; |
6b0bfe93 | 451 | |
903e21e2 EB |
452 | if (!!sysfs_ns_type(acxt->parent_sd) != !!sd->s_ns) { |
453 | WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", | |
454 | sysfs_ns_type(acxt->parent_sd)? "required": "invalid", | |
455 | acxt->parent_sd->s_name, sd->s_name); | |
456 | return -EINVAL; | |
457 | } | |
458 | ||
4e4d6d86 | 459 | sd->s_hash = sysfs_name_hash(sd->s_ns, sd->s_name); |
fb6896da TH |
460 | sd->s_parent = sysfs_get(acxt->parent_sd); |
461 | ||
4e4d6d86 EB |
462 | ret = sysfs_link_sibling(sd); |
463 | if (ret) | |
464 | return ret; | |
23dc2799 | 465 | |
6b0bfe93 EB |
466 | /* Update timestamps on the parent */ |
467 | ps_iattr = acxt->parent_sd->s_iattr; | |
468 | if (ps_iattr) { | |
469 | struct iattr *ps_iattrs = &ps_iattr->ia_iattr; | |
470 | ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; | |
471 | } | |
472 | ||
bb2b0051 ML |
473 | /* Mark the entry added into directory tree */ |
474 | sd->s_flags &= ~SYSFS_FLAG_REMOVED; | |
475 | ||
23dc2799 | 476 | return 0; |
fb6896da TH |
477 | } |
478 | ||
425cb029 AC |
479 | /** |
480 | * sysfs_pathname - return full path to sysfs dirent | |
481 | * @sd: sysfs_dirent whose path we want | |
66081a72 | 482 | * @path: caller allocated buffer of size PATH_MAX |
425cb029 AC |
483 | * |
484 | * Gives the name "/" to the sysfs_root entry; any path returned | |
485 | * is relative to wherever sysfs is mounted. | |
425cb029 AC |
486 | */ |
487 | static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) | |
488 | { | |
489 | if (sd->s_parent) { | |
490 | sysfs_pathname(sd->s_parent, path); | |
66081a72 | 491 | strlcat(path, "/", PATH_MAX); |
425cb029 | 492 | } |
66081a72 | 493 | strlcat(path, sd->s_name, PATH_MAX); |
425cb029 AC |
494 | return path; |
495 | } | |
496 | ||
36ce6dad CH |
497 | /** |
498 | * sysfs_add_one - add sysfs_dirent to parent | |
499 | * @acxt: addrm context to use | |
500 | * @sd: sysfs_dirent to be added | |
501 | * | |
502 | * Get @acxt->parent_sd and set sd->s_parent to it and increment | |
503 | * nlink of parent inode if @sd is a directory and link into the | |
504 | * children list of the parent. | |
505 | * | |
506 | * This function should be called between calls to | |
507 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be | |
508 | * passed the same @acxt as passed to sysfs_addrm_start(). | |
509 | * | |
510 | * LOCKING: | |
511 | * Determined by sysfs_addrm_start(). | |
512 | * | |
513 | * RETURNS: | |
514 | * 0 on success, -EEXIST if entry with the given name already | |
515 | * exists. | |
516 | */ | |
517 | int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) | |
518 | { | |
519 | int ret; | |
520 | ||
521 | ret = __sysfs_add_one(acxt, sd); | |
425cb029 AC |
522 | if (ret == -EEXIST) { |
523 | char *path = kzalloc(PATH_MAX, GFP_KERNEL); | |
524 | WARN(1, KERN_WARNING | |
525 | "sysfs: cannot create duplicate filename '%s'\n", | |
66081a72 GU |
526 | (path == NULL) ? sd->s_name |
527 | : (sysfs_pathname(acxt->parent_sd, path), | |
528 | strlcat(path, "/", PATH_MAX), | |
529 | strlcat(path, sd->s_name, PATH_MAX), | |
530 | path)); | |
425cb029 AC |
531 | kfree(path); |
532 | } | |
533 | ||
36ce6dad CH |
534 | return ret; |
535 | } | |
536 | ||
fb6896da TH |
537 | /** |
538 | * sysfs_remove_one - remove sysfs_dirent from parent | |
539 | * @acxt: addrm context to use | |
9fd5b1c9 | 540 | * @sd: sysfs_dirent to be removed |
fb6896da TH |
541 | * |
542 | * Mark @sd removed and drop nlink of parent inode if @sd is a | |
181b2e4b | 543 | * directory. @sd is unlinked from the children list. |
fb6896da TH |
544 | * |
545 | * This function should be called between calls to | |
546 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be | |
547 | * passed the same @acxt as passed to sysfs_addrm_start(). | |
548 | * | |
549 | * LOCKING: | |
550 | * Determined by sysfs_addrm_start(). | |
551 | */ | |
552 | void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) | |
553 | { | |
6b0bfe93 EB |
554 | struct sysfs_inode_attrs *ps_iattr; |
555 | ||
41fc1c27 TH |
556 | BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED); |
557 | ||
558 | sysfs_unlink_sibling(sd); | |
fb6896da | 559 | |
6b0bfe93 EB |
560 | /* Update timestamps on the parent */ |
561 | ps_iattr = acxt->parent_sd->s_iattr; | |
562 | if (ps_iattr) { | |
563 | struct iattr *ps_iattrs = &ps_iattr->ia_iattr; | |
564 | ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; | |
565 | } | |
566 | ||
fb6896da | 567 | sd->s_flags |= SYSFS_FLAG_REMOVED; |
58f2a4c7 | 568 | sd->u.removed_list = acxt->removed; |
fb6896da | 569 | acxt->removed = sd; |
a0edd7c8 TH |
570 | } |
571 | ||
fb6896da TH |
572 | /** |
573 | * sysfs_addrm_finish - finish up sysfs_dirent add/remove | |
574 | * @acxt: addrm context to finish up | |
575 | * | |
576 | * Finish up sysfs_dirent add/remove. Resources acquired by | |
577 | * sysfs_addrm_start() are released and removed sysfs_dirents are | |
a16bbc34 | 578 | * cleaned up. |
fb6896da TH |
579 | * |
580 | * LOCKING: | |
a16bbc34 | 581 | * sysfs_mutex is released. |
fb6896da | 582 | */ |
990e53f8 | 583 | void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) |
fb6896da TH |
584 | { |
585 | /* release resources acquired by sysfs_addrm_start() */ | |
586 | mutex_unlock(&sysfs_mutex); | |
fb6896da TH |
587 | |
588 | /* kill removed sysfs_dirents */ | |
589 | while (acxt->removed) { | |
590 | struct sysfs_dirent *sd = acxt->removed; | |
591 | ||
58f2a4c7 | 592 | acxt->removed = sd->u.removed_list; |
fb6896da | 593 | |
fb6896da | 594 | sysfs_deactivate(sd); |
e0edd3c6 | 595 | unmap_bin_file(sd); |
fb6896da | 596 | sysfs_put(sd); |
13b3086d | 597 | } |
b592fcfe EB |
598 | } |
599 | ||
f0b0af47 TH |
600 | /** |
601 | * sysfs_find_dirent - find sysfs_dirent with the given name | |
602 | * @parent_sd: sysfs_dirent to search under | |
603 | * @name: name to look for | |
604 | * | |
605 | * Look for sysfs_dirent with name @name under @parent_sd. | |
c516865c | 606 | * |
f0b0af47 | 607 | * LOCKING: |
3007e997 | 608 | * mutex_lock(sysfs_mutex) |
c516865c | 609 | * |
f0b0af47 TH |
610 | * RETURNS: |
611 | * Pointer to sysfs_dirent if found, NULL if not. | |
c516865c | 612 | */ |
f0b0af47 | 613 | struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, |
3ff195b0 | 614 | const void *ns, |
f0b0af47 | 615 | const unsigned char *name) |
c516865c | 616 | { |
4e4d6d86 EB |
617 | struct rb_node *node = parent_sd->s_dir.children.rb_node; |
618 | unsigned int hash; | |
4f72c0ca | 619 | |
903e21e2 EB |
620 | if (!!sysfs_ns_type(parent_sd) != !!ns) { |
621 | WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", | |
622 | sysfs_ns_type(parent_sd)? "required": "invalid", | |
623 | parent_sd->s_name, name); | |
624 | return NULL; | |
625 | } | |
626 | ||
4e4d6d86 EB |
627 | hash = sysfs_name_hash(ns, name); |
628 | while (node) { | |
629 | struct sysfs_dirent *sd; | |
630 | int result; | |
631 | ||
632 | sd = to_sysfs_dirent(node); | |
633 | result = sysfs_name_compare(hash, ns, name, sd); | |
634 | if (result < 0) | |
635 | node = node->rb_left; | |
636 | else if (result > 0) | |
637 | node = node->rb_right; | |
638 | else | |
639 | return sd; | |
3ff195b0 | 640 | } |
4e4d6d86 | 641 | return NULL; |
f0b0af47 | 642 | } |
c516865c | 643 | |
f0b0af47 TH |
644 | /** |
645 | * sysfs_get_dirent - find and get sysfs_dirent with the given name | |
646 | * @parent_sd: sysfs_dirent to search under | |
647 | * @name: name to look for | |
648 | * | |
649 | * Look for sysfs_dirent with name @name under @parent_sd and get | |
650 | * it if found. | |
651 | * | |
652 | * LOCKING: | |
3007e997 | 653 | * Kernel thread context (may sleep). Grabs sysfs_mutex. |
f0b0af47 TH |
654 | * |
655 | * RETURNS: | |
656 | * Pointer to sysfs_dirent if found, NULL if not. | |
657 | */ | |
658 | struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, | |
3ff195b0 | 659 | const void *ns, |
f0b0af47 TH |
660 | const unsigned char *name) |
661 | { | |
662 | struct sysfs_dirent *sd; | |
663 | ||
3007e997 | 664 | mutex_lock(&sysfs_mutex); |
3ff195b0 | 665 | sd = sysfs_find_dirent(parent_sd, ns, name); |
f0b0af47 | 666 | sysfs_get(sd); |
3007e997 | 667 | mutex_unlock(&sysfs_mutex); |
f0b0af47 TH |
668 | |
669 | return sd; | |
c516865c | 670 | } |
f1282c84 | 671 | EXPORT_SYMBOL_GPL(sysfs_get_dirent); |
c516865c | 672 | |
608e266a | 673 | static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, |
3ff195b0 EB |
674 | enum kobj_ns_type type, const void *ns, const char *name, |
675 | struct sysfs_dirent **p_sd) | |
1da177e4 | 676 | { |
1da177e4 | 677 | umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; |
51225039 | 678 | struct sysfs_addrm_cxt acxt; |
dfeb9fb0 | 679 | struct sysfs_dirent *sd; |
23dc2799 | 680 | int rc; |
1da177e4 | 681 | |
fc9f54b9 | 682 | /* allocate */ |
3e519038 | 683 | sd = sysfs_new_dirent(name, mode, SYSFS_DIR); |
a26cd722 | 684 | if (!sd) |
51225039 | 685 | return -ENOMEM; |
3ff195b0 EB |
686 | |
687 | sd->s_flags |= (type << SYSFS_NS_TYPE_SHIFT); | |
688 | sd->s_ns = ns; | |
b1fc3d61 | 689 | sd->s_dir.kobj = kobj; |
dfeb9fb0 | 690 | |
fc9f54b9 | 691 | /* link in */ |
51225039 | 692 | sysfs_addrm_start(&acxt, parent_sd); |
23dc2799 TH |
693 | rc = sysfs_add_one(&acxt, sd); |
694 | sysfs_addrm_finish(&acxt); | |
967e35dc | 695 | |
23dc2799 TH |
696 | if (rc == 0) |
697 | *p_sd = sd; | |
698 | else | |
967e35dc | 699 | sysfs_put(sd); |
dfeb9fb0 | 700 | |
23dc2799 | 701 | return rc; |
1da177e4 LT |
702 | } |
703 | ||
608e266a TH |
704 | int sysfs_create_subdir(struct kobject *kobj, const char *name, |
705 | struct sysfs_dirent **p_sd) | |
1da177e4 | 706 | { |
3ff195b0 EB |
707 | return create_dir(kobj, kobj->sd, |
708 | KOBJ_NS_TYPE_NONE, NULL, name, p_sd); | |
709 | } | |
710 | ||
be867b19 SH |
711 | /** |
712 | * sysfs_read_ns_type: return associated ns_type | |
713 | * @kobj: the kobject being queried | |
714 | * | |
715 | * Each kobject can be tagged with exactly one namespace type | |
716 | * (i.e. network or user). Return the ns_type associated with | |
717 | * this object if any | |
718 | */ | |
3ff195b0 EB |
719 | static enum kobj_ns_type sysfs_read_ns_type(struct kobject *kobj) |
720 | { | |
721 | const struct kobj_ns_type_operations *ops; | |
722 | enum kobj_ns_type type; | |
723 | ||
724 | ops = kobj_child_ns_ops(kobj); | |
725 | if (!ops) | |
726 | return KOBJ_NS_TYPE_NONE; | |
727 | ||
728 | type = ops->type; | |
729 | BUG_ON(type <= KOBJ_NS_TYPE_NONE); | |
730 | BUG_ON(type >= KOBJ_NS_TYPES); | |
731 | BUG_ON(!kobj_ns_type_registered(type)); | |
732 | ||
733 | return type; | |
1da177e4 LT |
734 | } |
735 | ||
736 | /** | |
737 | * sysfs_create_dir - create a directory for an object. | |
1da177e4 LT |
738 | * @kobj: object we're creating directory for. |
739 | */ | |
90bc6135 | 740 | int sysfs_create_dir(struct kobject * kobj) |
1da177e4 | 741 | { |
3ff195b0 | 742 | enum kobj_ns_type type; |
608e266a | 743 | struct sysfs_dirent *parent_sd, *sd; |
3ff195b0 | 744 | const void *ns = NULL; |
1da177e4 LT |
745 | int error = 0; |
746 | ||
747 | BUG_ON(!kobj); | |
748 | ||
90bc6135 | 749 | if (kobj->parent) |
608e266a | 750 | parent_sd = kobj->parent->sd; |
1da177e4 | 751 | else |
7d0c7d67 | 752 | parent_sd = &sysfs_root; |
1da177e4 | 753 | |
3a198886 DW |
754 | if (!parent_sd) |
755 | return -ENOENT; | |
756 | ||
3ff195b0 EB |
757 | if (sysfs_ns_type(parent_sd)) |
758 | ns = kobj->ktype->namespace(kobj); | |
759 | type = sysfs_read_ns_type(kobj); | |
760 | ||
761 | error = create_dir(kobj, parent_sd, type, ns, kobject_name(kobj), &sd); | |
1da177e4 | 762 | if (!error) |
608e266a | 763 | kobj->sd = sd; |
1da177e4 LT |
764 | return error; |
765 | } | |
766 | ||
1da177e4 | 767 | static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 768 | unsigned int flags) |
1da177e4 | 769 | { |
6cb52147 | 770 | struct dentry *ret = NULL; |
3ff195b0 EB |
771 | struct dentry *parent = dentry->d_parent; |
772 | struct sysfs_dirent *parent_sd = parent->d_fsdata; | |
a7a04754 | 773 | struct sysfs_dirent *sd; |
fc9f54b9 | 774 | struct inode *inode; |
3ff195b0 EB |
775 | enum kobj_ns_type type; |
776 | const void *ns; | |
1da177e4 | 777 | |
6cb52147 TH |
778 | mutex_lock(&sysfs_mutex); |
779 | ||
3ff195b0 EB |
780 | type = sysfs_ns_type(parent_sd); |
781 | ns = sysfs_info(dir->i_sb)->ns[type]; | |
782 | ||
783 | sd = sysfs_find_dirent(parent_sd, ns, dentry->d_name.name); | |
1da177e4 | 784 | |
fc9f54b9 | 785 | /* no such entry */ |
e49452c6 TH |
786 | if (!sd) { |
787 | ret = ERR_PTR(-ENOENT); | |
6cb52147 | 788 | goto out_unlock; |
e49452c6 | 789 | } |
469796d1 | 790 | dentry->d_fsdata = sysfs_get(sd); |
fc9f54b9 TH |
791 | |
792 | /* attach dentry and inode */ | |
fac2622b | 793 | inode = sysfs_get_inode(dir->i_sb, sd); |
6cb52147 TH |
794 | if (!inode) { |
795 | ret = ERR_PTR(-ENOMEM); | |
796 | goto out_unlock; | |
797 | } | |
3007e997 | 798 | |
d6b4fd2f | 799 | /* instantiate and hash dentry */ |
e77fb7ce | 800 | ret = d_materialise_unique(dentry, inode); |
6cb52147 | 801 | out_unlock: |
3007e997 | 802 | mutex_unlock(&sysfs_mutex); |
6cb52147 | 803 | return ret; |
1da177e4 LT |
804 | } |
805 | ||
c5ef1c42 | 806 | const struct inode_operations sysfs_dir_inode_operations = { |
1da177e4 | 807 | .lookup = sysfs_lookup, |
e61ab4ae | 808 | .permission = sysfs_permission, |
988d186d | 809 | .setattr = sysfs_setattr, |
e61ab4ae | 810 | .getattr = sysfs_getattr, |
ddd29ec6 | 811 | .setxattr = sysfs_setxattr, |
1da177e4 LT |
812 | }; |
813 | ||
608e266a | 814 | static void remove_dir(struct sysfs_dirent *sd) |
1da177e4 | 815 | { |
fb6896da | 816 | struct sysfs_addrm_cxt acxt; |
1da177e4 | 817 | |
fb6896da | 818 | sysfs_addrm_start(&acxt, sd->s_parent); |
fb6896da TH |
819 | sysfs_remove_one(&acxt, sd); |
820 | sysfs_addrm_finish(&acxt); | |
1da177e4 LT |
821 | } |
822 | ||
608e266a | 823 | void sysfs_remove_subdir(struct sysfs_dirent *sd) |
1da177e4 | 824 | { |
608e266a | 825 | remove_dir(sd); |
1da177e4 LT |
826 | } |
827 | ||
828 | ||
608e266a | 829 | static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) |
1da177e4 | 830 | { |
fb6896da | 831 | struct sysfs_addrm_cxt acxt; |
a406f758 | 832 | struct rb_node *pos; |
1da177e4 | 833 | |
608e266a | 834 | if (!dir_sd) |
1da177e4 LT |
835 | return; |
836 | ||
608e266a | 837 | pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); |
fb6896da | 838 | sysfs_addrm_start(&acxt, dir_sd); |
4e4d6d86 | 839 | pos = rb_first(&dir_sd->s_dir.children); |
a406f758 | 840 | while (pos) { |
4e4d6d86 | 841 | struct sysfs_dirent *sd = to_sysfs_dirent(pos); |
a406f758 | 842 | pos = rb_next(pos); |
3efa65b9 | 843 | if (sysfs_type(sd) != SYSFS_DIR) |
fb6896da | 844 | sysfs_remove_one(&acxt, sd); |
1da177e4 | 845 | } |
fb6896da | 846 | sysfs_addrm_finish(&acxt); |
0ab66088 | 847 | |
608e266a | 848 | remove_dir(dir_sd); |
b592fcfe EB |
849 | } |
850 | ||
851 | /** | |
852 | * sysfs_remove_dir - remove an object's directory. | |
853 | * @kobj: object. | |
854 | * | |
855 | * The only thing special about this is that we remove any files in | |
856 | * the directory before we remove the directory, and we've inlined | |
857 | * what used to be sysfs_rmdir() below, instead of calling separately. | |
858 | */ | |
859 | ||
860 | void sysfs_remove_dir(struct kobject * kobj) | |
861 | { | |
608e266a | 862 | struct sysfs_dirent *sd = kobj->sd; |
aecdceda | 863 | |
5f995323 | 864 | spin_lock(&sysfs_assoc_lock); |
608e266a | 865 | kobj->sd = NULL; |
5f995323 | 866 | spin_unlock(&sysfs_assoc_lock); |
aecdceda | 867 | |
608e266a | 868 | __sysfs_remove_dir(sd); |
1da177e4 LT |
869 | } |
870 | ||
ca1bab38 | 871 | int sysfs_rename(struct sysfs_dirent *sd, |
3ff195b0 EB |
872 | struct sysfs_dirent *new_parent_sd, const void *new_ns, |
873 | const char *new_name) | |
1da177e4 | 874 | { |
996b7376 | 875 | int error; |
1da177e4 | 876 | |
832b6af1 | 877 | mutex_lock(&sysfs_mutex); |
932ea2e3 | 878 | |
9918f9a4 | 879 | error = 0; |
3ff195b0 | 880 | if ((sd->s_parent == new_parent_sd) && (sd->s_ns == new_ns) && |
ca1bab38 | 881 | (strcmp(sd->s_name, new_name) == 0)) |
9918f9a4 EB |
882 | goto out; /* nothing to rename */ |
883 | ||
9918f9a4 | 884 | error = -EEXIST; |
3ff195b0 | 885 | if (sysfs_find_dirent(new_parent_sd, new_ns, new_name)) |
832b6af1 | 886 | goto out; |
996b7376 | 887 | |
0b4a4fea | 888 | /* rename sysfs_dirent */ |
ca1bab38 EB |
889 | if (strcmp(sd->s_name, new_name) != 0) { |
890 | error = -ENOMEM; | |
b4eafca1 | 891 | new_name = kstrdup(new_name, GFP_KERNEL); |
ca1bab38 EB |
892 | if (!new_name) |
893 | goto out; | |
894 | ||
b4eafca1 | 895 | kfree(sd->s_name); |
ca1bab38 EB |
896 | sd->s_name = new_name; |
897 | } | |
0c096b50 | 898 | |
f6d90b4f EB |
899 | /* Move to the appropriate place in the appropriate directories rbtree. */ |
900 | sysfs_unlink_sibling(sd); | |
901 | sysfs_get(new_parent_sd); | |
902 | sysfs_put(sd->s_parent); | |
3ff195b0 | 903 | sd->s_ns = new_ns; |
70fa4a62 | 904 | sd->s_hash = sysfs_name_hash(sd->s_ns, sd->s_name); |
f6d90b4f EB |
905 | sd->s_parent = new_parent_sd; |
906 | sysfs_link_sibling(sd); | |
0c096b50 | 907 | |
996b7376 | 908 | error = 0; |
832b6af1 | 909 | out: |
9918f9a4 | 910 | mutex_unlock(&sysfs_mutex); |
1da177e4 LT |
911 | return error; |
912 | } | |
913 | ||
ca1bab38 EB |
914 | int sysfs_rename_dir(struct kobject *kobj, const char *new_name) |
915 | { | |
3ff195b0 EB |
916 | struct sysfs_dirent *parent_sd = kobj->sd->s_parent; |
917 | const void *new_ns = NULL; | |
918 | ||
919 | if (sysfs_ns_type(parent_sd)) | |
920 | new_ns = kobj->ktype->namespace(kobj); | |
921 | ||
922 | return sysfs_rename(kobj->sd, parent_sd, new_ns, new_name); | |
ca1bab38 EB |
923 | } |
924 | ||
51225039 | 925 | int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) |
8a82472f | 926 | { |
51225039 TH |
927 | struct sysfs_dirent *sd = kobj->sd; |
928 | struct sysfs_dirent *new_parent_sd; | |
3ff195b0 | 929 | const void *new_ns = NULL; |
8a82472f | 930 | |
51225039 | 931 | BUG_ON(!sd->s_parent); |
3ff195b0 EB |
932 | if (sysfs_ns_type(sd->s_parent)) |
933 | new_ns = kobj->ktype->namespace(kobj); | |
ca1bab38 | 934 | new_parent_sd = new_parent_kobj && new_parent_kobj->sd ? |
a6a83577 | 935 | new_parent_kobj->sd : &sysfs_root; |
51225039 | 936 | |
3ff195b0 | 937 | return sysfs_rename(sd, new_parent_sd, new_ns, sd->s_name); |
8a82472f CH |
938 | } |
939 | ||
1da177e4 LT |
940 | /* Relationship between s_mode and the DT_xxx types */ |
941 | static inline unsigned char dt_type(struct sysfs_dirent *sd) | |
942 | { | |
943 | return (sd->s_mode >> 12) & 15; | |
944 | } | |
945 | ||
1e5289c9 EB |
946 | static int sysfs_dir_release(struct inode *inode, struct file *filp) |
947 | { | |
948 | sysfs_put(filp->private_data); | |
949 | return 0; | |
950 | } | |
951 | ||
3ff195b0 | 952 | static struct sysfs_dirent *sysfs_dir_pos(const void *ns, |
4e4d6d86 | 953 | struct sysfs_dirent *parent_sd, loff_t hash, struct sysfs_dirent *pos) |
1e5289c9 EB |
954 | { |
955 | if (pos) { | |
956 | int valid = !(pos->s_flags & SYSFS_FLAG_REMOVED) && | |
957 | pos->s_parent == parent_sd && | |
4e4d6d86 | 958 | hash == pos->s_hash; |
1e5289c9 | 959 | sysfs_put(pos); |
3ff195b0 EB |
960 | if (!valid) |
961 | pos = NULL; | |
1e5289c9 | 962 | } |
4e4d6d86 EB |
963 | if (!pos && (hash > 1) && (hash < INT_MAX)) { |
964 | struct rb_node *node = parent_sd->s_dir.children.rb_node; | |
965 | while (node) { | |
966 | pos = to_sysfs_dirent(node); | |
967 | ||
968 | if (hash < pos->s_hash) | |
969 | node = node->rb_left; | |
970 | else if (hash > pos->s_hash) | |
971 | node = node->rb_right; | |
972 | else | |
a406f758 | 973 | break; |
a406f758 MP |
974 | } |
975 | } | |
4e4d6d86 | 976 | /* Skip over entries in the wrong namespace */ |
b9e2780d | 977 | while (pos && pos->s_ns != ns) { |
4e4d6d86 EB |
978 | struct rb_node *node = rb_next(&pos->s_rb); |
979 | if (!node) | |
a406f758 MP |
980 | pos = NULL; |
981 | else | |
4e4d6d86 | 982 | pos = to_sysfs_dirent(node); |
1e5289c9 EB |
983 | } |
984 | return pos; | |
985 | } | |
986 | ||
3ff195b0 EB |
987 | static struct sysfs_dirent *sysfs_dir_next_pos(const void *ns, |
988 | struct sysfs_dirent *parent_sd, ino_t ino, struct sysfs_dirent *pos) | |
1e5289c9 | 989 | { |
3ff195b0 | 990 | pos = sysfs_dir_pos(ns, parent_sd, ino, pos); |
a406f758 | 991 | if (pos) do { |
4e4d6d86 EB |
992 | struct rb_node *node = rb_next(&pos->s_rb); |
993 | if (!node) | |
a406f758 MP |
994 | pos = NULL; |
995 | else | |
4e4d6d86 | 996 | pos = to_sysfs_dirent(node); |
b9e2780d | 997 | } while (pos && pos->s_ns != ns); |
1e5289c9 EB |
998 | return pos; |
999 | } | |
1000 | ||
d55fea8d | 1001 | static int sysfs_readdir(struct file *file, struct dir_context *ctx) |
1da177e4 | 1002 | { |
d55fea8d | 1003 | struct dentry *dentry = file->f_path.dentry; |
1da177e4 | 1004 | struct sysfs_dirent * parent_sd = dentry->d_fsdata; |
d55fea8d | 1005 | struct sysfs_dirent *pos = file->private_data; |
3ff195b0 EB |
1006 | enum kobj_ns_type type; |
1007 | const void *ns; | |
1da177e4 | 1008 | |
3ff195b0 EB |
1009 | type = sysfs_ns_type(parent_sd); |
1010 | ns = sysfs_info(dentry->d_sb)->ns[type]; | |
1011 | ||
d55fea8d AV |
1012 | if (!dir_emit_dots(file, ctx)) |
1013 | return 0; | |
1e5289c9 | 1014 | mutex_lock(&sysfs_mutex); |
d55fea8d | 1015 | for (pos = sysfs_dir_pos(ns, parent_sd, ctx->pos, pos); |
1e5289c9 | 1016 | pos; |
d55fea8d AV |
1017 | pos = sysfs_dir_next_pos(ns, parent_sd, ctx->pos, pos)) { |
1018 | const char *name = pos->s_name; | |
1019 | unsigned int type = dt_type(pos); | |
1020 | int len = strlen(name); | |
1021 | ino_t ino = pos->s_ino; | |
1022 | ctx->pos = pos->s_hash; | |
1023 | file->private_data = sysfs_get(pos); | |
1da177e4 | 1024 | |
3007e997 | 1025 | mutex_unlock(&sysfs_mutex); |
d55fea8d AV |
1026 | if (!dir_emit(ctx, name, len, ino, type)) |
1027 | return 0; | |
1e5289c9 | 1028 | mutex_lock(&sysfs_mutex); |
1e5289c9 EB |
1029 | } |
1030 | mutex_unlock(&sysfs_mutex); | |
d55fea8d AV |
1031 | file->private_data = NULL; |
1032 | ctx->pos = INT_MAX; | |
3efa65b9 | 1033 | return 0; |
1da177e4 LT |
1034 | } |
1035 | ||
991f76f8 ML |
1036 | static loff_t sysfs_dir_llseek(struct file *file, loff_t offset, int whence) |
1037 | { | |
1038 | struct inode *inode = file_inode(file); | |
1039 | loff_t ret; | |
1040 | ||
1041 | mutex_lock(&inode->i_mutex); | |
1042 | ret = generic_file_llseek(file, offset, whence); | |
1043 | mutex_unlock(&inode->i_mutex); | |
1044 | ||
1045 | return ret; | |
1046 | } | |
3efa65b9 | 1047 | |
4b6f5d20 | 1048 | const struct file_operations sysfs_dir_operations = { |
1da177e4 | 1049 | .read = generic_read_dir, |
d55fea8d | 1050 | .iterate = sysfs_readdir, |
1e5289c9 | 1051 | .release = sysfs_dir_release, |
991f76f8 | 1052 | .llseek = sysfs_dir_llseek, |
1da177e4 | 1053 | }; |