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Commit | Line | Data |
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55716d26 | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
b8441ed2 TH |
2 | /* |
3 | * kernfs.h - pseudo filesystem decoupled from vfs locking | |
b8441ed2 TH |
4 | */ |
5 | ||
6 | #ifndef __LINUX_KERNFS_H | |
7 | #define __LINUX_KERNFS_H | |
8 | ||
879f40d1 | 9 | #include <linux/kernel.h> |
5d0e26bb | 10 | #include <linux/err.h> |
dd8a5b03 TH |
11 | #include <linux/list.h> |
12 | #include <linux/mutex.h> | |
bc755553 | 13 | #include <linux/idr.h> |
517e64f5 | 14 | #include <linux/lockdep.h> |
cf9e5a73 TH |
15 | #include <linux/rbtree.h> |
16 | #include <linux/atomic.h> | |
488dee96 | 17 | #include <linux/uidgid.h> |
abd54f02 | 18 | #include <linux/wait.h> |
879f40d1 | 19 | |
5d60418e | 20 | struct file; |
917f56ca | 21 | struct dentry; |
5d60418e | 22 | struct iattr; |
dd8a5b03 TH |
23 | struct seq_file; |
24 | struct vm_area_struct; | |
4b93dc9b TH |
25 | struct super_block; |
26 | struct file_system_type; | |
147e1a97 | 27 | struct poll_table_struct; |
23bf1b6b | 28 | struct fs_context; |
5d60418e | 29 | |
23bf1b6b | 30 | struct kernfs_fs_context; |
c525aadd TH |
31 | struct kernfs_open_node; |
32 | struct kernfs_iattrs; | |
cf9e5a73 TH |
33 | |
34 | enum kernfs_node_type { | |
df23fc39 TH |
35 | KERNFS_DIR = 0x0001, |
36 | KERNFS_FILE = 0x0002, | |
37 | KERNFS_LINK = 0x0004, | |
cf9e5a73 TH |
38 | }; |
39 | ||
0c47383b DX |
40 | #define KERNFS_TYPE_MASK 0x000f |
41 | #define KERNFS_FLAG_MASK ~KERNFS_TYPE_MASK | |
42 | #define KERNFS_MAX_USER_XATTRS 128 | |
43 | #define KERNFS_USER_XATTR_SIZE_LIMIT (128 << 10) | |
cf9e5a73 TH |
44 | |
45 | enum kernfs_node_flag { | |
d35258ef | 46 | KERNFS_ACTIVATED = 0x0010, |
df23fc39 TH |
47 | KERNFS_NS = 0x0020, |
48 | KERNFS_HAS_SEQ_SHOW = 0x0040, | |
49 | KERNFS_HAS_MMAP = 0x0080, | |
50 | KERNFS_LOCKDEP = 0x0100, | |
6b0afc2a TH |
51 | KERNFS_SUICIDAL = 0x0400, |
52 | KERNFS_SUICIDED = 0x0800, | |
ea015218 | 53 | KERNFS_EMPTY_DIR = 0x1000, |
0e67db2f | 54 | KERNFS_HAS_RELEASE = 0x2000, |
cf9e5a73 TH |
55 | }; |
56 | ||
d35258ef TH |
57 | /* @flags for kernfs_create_root() */ |
58 | enum kernfs_root_flag { | |
555724a8 TH |
59 | /* |
60 | * kernfs_nodes are created in the deactivated state and invisible. | |
61 | * They require explicit kernfs_activate() to become visible. This | |
62 | * can be used to make related nodes become visible atomically | |
63 | * after all nodes are created successfully. | |
64 | */ | |
65 | KERNFS_ROOT_CREATE_DEACTIVATED = 0x0001, | |
66 | ||
67 | /* | |
0d1a393d | 68 | * For regular files, if the opener has CAP_DAC_OVERRIDE, open(2) |
555724a8 TH |
69 | * succeeds regardless of the RW permissions. sysfs had an extra |
70 | * layer of enforcement where open(2) fails with -EACCES regardless | |
71 | * of CAP_DAC_OVERRIDE if the permission doesn't have the | |
72 | * respective read or write access at all (none of S_IRUGO or | |
73 | * S_IWUGO) or the respective operation isn't implemented. The | |
74 | * following flag enables that behavior. | |
75 | */ | |
76 | KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK = 0x0002, | |
aa818825 SL |
77 | |
78 | /* | |
79 | * The filesystem supports exportfs operation, so userspace can use | |
80 | * fhandle to access nodes of the fs. | |
81 | */ | |
82 | KERNFS_ROOT_SUPPORT_EXPORTOP = 0x0004, | |
0c47383b DX |
83 | |
84 | /* | |
85 | * Support user xattrs to be written to nodes rooted at this root. | |
86 | */ | |
87 | KERNFS_ROOT_SUPPORT_USER_XATTR = 0x0008, | |
d35258ef TH |
88 | }; |
89 | ||
324a56e1 TH |
90 | /* type-specific structures for kernfs_node union members */ |
91 | struct kernfs_elem_dir { | |
cf9e5a73 | 92 | unsigned long subdirs; |
adc5e8b5 | 93 | /* children rbtree starts here and goes through kn->rb */ |
cf9e5a73 TH |
94 | struct rb_root children; |
95 | ||
96 | /* | |
97 | * The kernfs hierarchy this directory belongs to. This fits | |
324a56e1 | 98 | * better directly in kernfs_node but is here to save space. |
cf9e5a73 TH |
99 | */ |
100 | struct kernfs_root *root; | |
101 | }; | |
102 | ||
324a56e1 TH |
103 | struct kernfs_elem_symlink { |
104 | struct kernfs_node *target_kn; | |
cf9e5a73 TH |
105 | }; |
106 | ||
324a56e1 | 107 | struct kernfs_elem_attr { |
cf9e5a73 | 108 | const struct kernfs_ops *ops; |
c525aadd | 109 | struct kernfs_open_node *open; |
cf9e5a73 | 110 | loff_t size; |
ecca47ce | 111 | struct kernfs_node *notify_next; /* for kernfs_notify() */ |
cf9e5a73 TH |
112 | }; |
113 | ||
114 | /* | |
324a56e1 TH |
115 | * kernfs_node - the building block of kernfs hierarchy. Each and every |
116 | * kernfs node is represented by single kernfs_node. Most fields are | |
cf9e5a73 TH |
117 | * private to kernfs and shouldn't be accessed directly by kernfs users. |
118 | * | |
21774fd8 | 119 | * As long as count reference is held, the kernfs_node itself is |
324a56e1 TH |
120 | * accessible. Dereferencing elem or any other outer entity requires |
121 | * active reference. | |
cf9e5a73 | 122 | */ |
324a56e1 | 123 | struct kernfs_node { |
adc5e8b5 TH |
124 | atomic_t count; |
125 | atomic_t active; | |
cf9e5a73 TH |
126 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
127 | struct lockdep_map dep_map; | |
128 | #endif | |
3eef34ad TH |
129 | /* |
130 | * Use kernfs_get_parent() and kernfs_name/path() instead of | |
131 | * accessing the following two fields directly. If the node is | |
132 | * never moved to a different parent, it is safe to access the | |
133 | * parent directly. | |
134 | */ | |
adc5e8b5 TH |
135 | struct kernfs_node *parent; |
136 | const char *name; | |
cf9e5a73 | 137 | |
adc5e8b5 | 138 | struct rb_node rb; |
cf9e5a73 | 139 | |
adc5e8b5 | 140 | const void *ns; /* namespace tag */ |
9b0925a6 | 141 | unsigned int hash; /* ns + name hash */ |
cf9e5a73 | 142 | union { |
adc5e8b5 TH |
143 | struct kernfs_elem_dir dir; |
144 | struct kernfs_elem_symlink symlink; | |
145 | struct kernfs_elem_attr attr; | |
cf9e5a73 TH |
146 | }; |
147 | ||
148 | void *priv; | |
149 | ||
67c0496e | 150 | /* |
40430452 TH |
151 | * 64bit unique ID. On 64bit ino setups, id is the ino. On 32bit, |
152 | * the low 32bits are ino and upper generation. | |
67c0496e TH |
153 | */ |
154 | u64 id; | |
155 | ||
adc5e8b5 TH |
156 | unsigned short flags; |
157 | umode_t mode; | |
c525aadd | 158 | struct kernfs_iattrs *iattr; |
cf9e5a73 | 159 | }; |
b8441ed2 | 160 | |
80b9bbef | 161 | /* |
90c07c89 TH |
162 | * kernfs_syscall_ops may be specified on kernfs_create_root() to support |
163 | * syscalls. These optional callbacks are invoked on the matching syscalls | |
164 | * and can perform any kernfs operations which don't necessarily have to be | |
165 | * the exact operation requested. An active reference is held for each | |
166 | * kernfs_node parameter. | |
80b9bbef | 167 | */ |
90c07c89 | 168 | struct kernfs_syscall_ops { |
6a7fed4e TH |
169 | int (*show_options)(struct seq_file *sf, struct kernfs_root *root); |
170 | ||
80b9bbef TH |
171 | int (*mkdir)(struct kernfs_node *parent, const char *name, |
172 | umode_t mode); | |
173 | int (*rmdir)(struct kernfs_node *kn); | |
174 | int (*rename)(struct kernfs_node *kn, struct kernfs_node *new_parent, | |
175 | const char *new_name); | |
4f41fc59 SH |
176 | int (*show_path)(struct seq_file *sf, struct kernfs_node *kn, |
177 | struct kernfs_root *root); | |
80b9bbef TH |
178 | }; |
179 | ||
ba7443bc TH |
180 | struct kernfs_root { |
181 | /* published fields */ | |
324a56e1 | 182 | struct kernfs_node *kn; |
d35258ef | 183 | unsigned int flags; /* KERNFS_ROOT_* flags */ |
bc755553 TH |
184 | |
185 | /* private fields, do not use outside kernfs proper */ | |
7d35079f | 186 | struct idr ino_idr; |
40430452 TH |
187 | u32 last_id_lowbits; |
188 | u32 id_highbits; | |
90c07c89 | 189 | struct kernfs_syscall_ops *syscall_ops; |
7d568a83 TH |
190 | |
191 | /* list of kernfs_super_info of this root, protected by kernfs_mutex */ | |
192 | struct list_head supers; | |
193 | ||
abd54f02 | 194 | wait_queue_head_t deactivate_waitq; |
ba7443bc TH |
195 | }; |
196 | ||
c525aadd | 197 | struct kernfs_open_file { |
dd8a5b03 | 198 | /* published fields */ |
324a56e1 | 199 | struct kernfs_node *kn; |
dd8a5b03 | 200 | struct file *file; |
0e67db2f | 201 | struct seq_file *seq_file; |
2536390d | 202 | void *priv; |
dd8a5b03 TH |
203 | |
204 | /* private fields, do not use outside kernfs proper */ | |
205 | struct mutex mutex; | |
e4234a1f | 206 | struct mutex prealloc_mutex; |
dd8a5b03 TH |
207 | int event; |
208 | struct list_head list; | |
2b75869b | 209 | char *prealloc_buf; |
dd8a5b03 | 210 | |
b7ce40cf | 211 | size_t atomic_write_len; |
a1d82aff | 212 | bool mmapped:1; |
0e67db2f | 213 | bool released:1; |
dd8a5b03 TH |
214 | const struct vm_operations_struct *vm_ops; |
215 | }; | |
216 | ||
f6acf8bb | 217 | struct kernfs_ops { |
0e67db2f TH |
218 | /* |
219 | * Optional open/release methods. Both are called with | |
220 | * @of->seq_file populated. | |
221 | */ | |
222 | int (*open)(struct kernfs_open_file *of); | |
223 | void (*release)(struct kernfs_open_file *of); | |
224 | ||
f6acf8bb TH |
225 | /* |
226 | * Read is handled by either seq_file or raw_read(). | |
227 | * | |
d19b9846 TH |
228 | * If seq_show() is present, seq_file path is active. Other seq |
229 | * operations are optional and if not implemented, the behavior is | |
230 | * equivalent to single_open(). @sf->private points to the | |
c525aadd | 231 | * associated kernfs_open_file. |
f6acf8bb TH |
232 | * |
233 | * read() is bounced through kernel buffer and a read larger than | |
234 | * PAGE_SIZE results in partial operation of PAGE_SIZE. | |
235 | */ | |
236 | int (*seq_show)(struct seq_file *sf, void *v); | |
d19b9846 TH |
237 | |
238 | void *(*seq_start)(struct seq_file *sf, loff_t *ppos); | |
239 | void *(*seq_next)(struct seq_file *sf, void *v, loff_t *ppos); | |
240 | void (*seq_stop)(struct seq_file *sf, void *v); | |
f6acf8bb | 241 | |
c525aadd | 242 | ssize_t (*read)(struct kernfs_open_file *of, char *buf, size_t bytes, |
f6acf8bb TH |
243 | loff_t off); |
244 | ||
245 | /* | |
4d3773c4 TH |
246 | * write() is bounced through kernel buffer. If atomic_write_len |
247 | * is not set, a write larger than PAGE_SIZE results in partial | |
248 | * operations of PAGE_SIZE chunks. If atomic_write_len is set, | |
249 | * writes upto the specified size are executed atomically but | |
250 | * larger ones are rejected with -E2BIG. | |
f6acf8bb | 251 | */ |
4d3773c4 | 252 | size_t atomic_write_len; |
2b75869b N |
253 | /* |
254 | * "prealloc" causes a buffer to be allocated at open for | |
255 | * all read/write requests. As ->seq_show uses seq_read() | |
256 | * which does its own allocation, it is incompatible with | |
257 | * ->prealloc. Provide ->read and ->write with ->prealloc. | |
258 | */ | |
259 | bool prealloc; | |
c525aadd | 260 | ssize_t (*write)(struct kernfs_open_file *of, char *buf, size_t bytes, |
f6acf8bb TH |
261 | loff_t off); |
262 | ||
147e1a97 JW |
263 | __poll_t (*poll)(struct kernfs_open_file *of, |
264 | struct poll_table_struct *pt); | |
265 | ||
c525aadd | 266 | int (*mmap)(struct kernfs_open_file *of, struct vm_area_struct *vma); |
517e64f5 TH |
267 | |
268 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
269 | struct lock_class_key lockdep_key; | |
270 | #endif | |
f6acf8bb TH |
271 | }; |
272 | ||
23bf1b6b DH |
273 | /* |
274 | * The kernfs superblock creation/mount parameter context. | |
275 | */ | |
276 | struct kernfs_fs_context { | |
277 | struct kernfs_root *root; /* Root of the hierarchy being mounted */ | |
278 | void *ns_tag; /* Namespace tag of the mount (or NULL) */ | |
279 | unsigned long magic; /* File system specific magic number */ | |
280 | ||
281 | /* The following are set/used by kernfs_mount() */ | |
282 | bool new_sb_created; /* Set to T if we allocated a new sb */ | |
283 | }; | |
284 | ||
ba341d55 | 285 | #ifdef CONFIG_KERNFS |
879f40d1 | 286 | |
df23fc39 | 287 | static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn) |
cf9e5a73 | 288 | { |
df23fc39 | 289 | return kn->flags & KERNFS_TYPE_MASK; |
cf9e5a73 TH |
290 | } |
291 | ||
67c0496e TH |
292 | static inline ino_t kernfs_id_ino(u64 id) |
293 | { | |
40430452 TH |
294 | /* id is ino if ino_t is 64bit; otherwise, low 32bits */ |
295 | if (sizeof(ino_t) >= sizeof(u64)) | |
296 | return id; | |
297 | else | |
298 | return (u32)id; | |
67c0496e TH |
299 | } |
300 | ||
301 | static inline u32 kernfs_id_gen(u64 id) | |
302 | { | |
40430452 TH |
303 | /* gen is fixed at 1 if ino_t is 64bit; otherwise, high 32bits */ |
304 | if (sizeof(ino_t) >= sizeof(u64)) | |
305 | return 1; | |
306 | else | |
307 | return id >> 32; | |
67c0496e TH |
308 | } |
309 | ||
310 | static inline ino_t kernfs_ino(struct kernfs_node *kn) | |
311 | { | |
312 | return kernfs_id_ino(kn->id); | |
313 | } | |
314 | ||
315 | static inline ino_t kernfs_gen(struct kernfs_node *kn) | |
316 | { | |
317 | return kernfs_id_gen(kn->id); | |
318 | } | |
319 | ||
cf9e5a73 TH |
320 | /** |
321 | * kernfs_enable_ns - enable namespace under a directory | |
324a56e1 | 322 | * @kn: directory of interest, should be empty |
cf9e5a73 | 323 | * |
324a56e1 TH |
324 | * This is to be called right after @kn is created to enable namespace |
325 | * under it. All children of @kn must have non-NULL namespace tags and | |
cf9e5a73 TH |
326 | * only the ones which match the super_block's tag will be visible. |
327 | */ | |
324a56e1 | 328 | static inline void kernfs_enable_ns(struct kernfs_node *kn) |
cf9e5a73 | 329 | { |
df23fc39 | 330 | WARN_ON_ONCE(kernfs_type(kn) != KERNFS_DIR); |
adc5e8b5 | 331 | WARN_ON_ONCE(!RB_EMPTY_ROOT(&kn->dir.children)); |
df23fc39 | 332 | kn->flags |= KERNFS_NS; |
cf9e5a73 TH |
333 | } |
334 | ||
ac9bba03 TH |
335 | /** |
336 | * kernfs_ns_enabled - test whether namespace is enabled | |
324a56e1 | 337 | * @kn: the node to test |
ac9bba03 TH |
338 | * |
339 | * Test whether namespace filtering is enabled for the children of @ns. | |
340 | */ | |
324a56e1 | 341 | static inline bool kernfs_ns_enabled(struct kernfs_node *kn) |
ac9bba03 | 342 | { |
df23fc39 | 343 | return kn->flags & KERNFS_NS; |
ac9bba03 TH |
344 | } |
345 | ||
3eef34ad | 346 | int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen); |
9f6df573 AK |
347 | int kernfs_path_from_node(struct kernfs_node *root_kn, struct kernfs_node *kn, |
348 | char *buf, size_t buflen); | |
3eef34ad TH |
349 | void pr_cont_kernfs_name(struct kernfs_node *kn); |
350 | void pr_cont_kernfs_path(struct kernfs_node *kn); | |
351 | struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn); | |
324a56e1 TH |
352 | struct kernfs_node *kernfs_find_and_get_ns(struct kernfs_node *parent, |
353 | const char *name, const void *ns); | |
bd96f76a TH |
354 | struct kernfs_node *kernfs_walk_and_get_ns(struct kernfs_node *parent, |
355 | const char *path, const void *ns); | |
324a56e1 TH |
356 | void kernfs_get(struct kernfs_node *kn); |
357 | void kernfs_put(struct kernfs_node *kn); | |
ccf73cf3 | 358 | |
0c23b225 TH |
359 | struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry); |
360 | struct kernfs_root *kernfs_root_from_sb(struct super_block *sb); | |
fb02915f | 361 | struct inode *kernfs_get_inode(struct super_block *sb, struct kernfs_node *kn); |
0c23b225 | 362 | |
fb3c8315 AK |
363 | struct dentry *kernfs_node_dentry(struct kernfs_node *kn, |
364 | struct super_block *sb); | |
90c07c89 | 365 | struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops, |
d35258ef | 366 | unsigned int flags, void *priv); |
ba7443bc TH |
367 | void kernfs_destroy_root(struct kernfs_root *root); |
368 | ||
324a56e1 | 369 | struct kernfs_node *kernfs_create_dir_ns(struct kernfs_node *parent, |
bb8b9d09 | 370 | const char *name, umode_t mode, |
488dee96 | 371 | kuid_t uid, kgid_t gid, |
bb8b9d09 | 372 | void *priv, const void *ns); |
ea015218 EB |
373 | struct kernfs_node *kernfs_create_empty_dir(struct kernfs_node *parent, |
374 | const char *name); | |
2063d608 | 375 | struct kernfs_node *__kernfs_create_file(struct kernfs_node *parent, |
488dee96 DT |
376 | const char *name, umode_t mode, |
377 | kuid_t uid, kgid_t gid, | |
378 | loff_t size, | |
2063d608 TH |
379 | const struct kernfs_ops *ops, |
380 | void *priv, const void *ns, | |
2063d608 | 381 | struct lock_class_key *key); |
324a56e1 TH |
382 | struct kernfs_node *kernfs_create_link(struct kernfs_node *parent, |
383 | const char *name, | |
384 | struct kernfs_node *target); | |
d35258ef | 385 | void kernfs_activate(struct kernfs_node *kn); |
324a56e1 | 386 | void kernfs_remove(struct kernfs_node *kn); |
6b0afc2a TH |
387 | void kernfs_break_active_protection(struct kernfs_node *kn); |
388 | void kernfs_unbreak_active_protection(struct kernfs_node *kn); | |
389 | bool kernfs_remove_self(struct kernfs_node *kn); | |
324a56e1 | 390 | int kernfs_remove_by_name_ns(struct kernfs_node *parent, const char *name, |
879f40d1 | 391 | const void *ns); |
324a56e1 | 392 | int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent, |
890ece16 | 393 | const char *new_name, const void *new_ns); |
324a56e1 | 394 | int kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr); |
147e1a97 JW |
395 | __poll_t kernfs_generic_poll(struct kernfs_open_file *of, |
396 | struct poll_table_struct *pt); | |
324a56e1 | 397 | void kernfs_notify(struct kernfs_node *kn); |
879f40d1 | 398 | |
1537ad15 OM |
399 | int kernfs_xattr_get(struct kernfs_node *kn, const char *name, |
400 | void *value, size_t size); | |
401 | int kernfs_xattr_set(struct kernfs_node *kn, const char *name, | |
402 | const void *value, size_t size, int flags); | |
b230d5ab | 403 | |
4b93dc9b | 404 | const void *kernfs_super_ns(struct super_block *sb); |
23bf1b6b DH |
405 | int kernfs_get_tree(struct fs_context *fc); |
406 | void kernfs_free_fs_context(struct fs_context *fc); | |
4b93dc9b TH |
407 | void kernfs_kill_sb(struct super_block *sb); |
408 | ||
409 | void kernfs_init(void); | |
410 | ||
fe0f726c TH |
411 | struct kernfs_node *kernfs_find_and_get_node_by_id(struct kernfs_root *root, |
412 | u64 id); | |
ba341d55 | 413 | #else /* CONFIG_KERNFS */ |
879f40d1 | 414 | |
df23fc39 | 415 | static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn) |
cf9e5a73 TH |
416 | { return 0; } /* whatever */ |
417 | ||
324a56e1 | 418 | static inline void kernfs_enable_ns(struct kernfs_node *kn) { } |
cf9e5a73 | 419 | |
324a56e1 | 420 | static inline bool kernfs_ns_enabled(struct kernfs_node *kn) |
ac9bba03 TH |
421 | { return false; } |
422 | ||
3eef34ad TH |
423 | static inline int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen) |
424 | { return -ENOSYS; } | |
425 | ||
0e0b2afd TH |
426 | static inline int kernfs_path_from_node(struct kernfs_node *root_kn, |
427 | struct kernfs_node *kn, | |
428 | char *buf, size_t buflen) | |
429 | { return -ENOSYS; } | |
430 | ||
3eef34ad TH |
431 | static inline void pr_cont_kernfs_name(struct kernfs_node *kn) { } |
432 | static inline void pr_cont_kernfs_path(struct kernfs_node *kn) { } | |
433 | ||
434 | static inline struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn) | |
435 | { return NULL; } | |
436 | ||
324a56e1 TH |
437 | static inline struct kernfs_node * |
438 | kernfs_find_and_get_ns(struct kernfs_node *parent, const char *name, | |
ccf73cf3 TH |
439 | const void *ns) |
440 | { return NULL; } | |
bd96f76a TH |
441 | static inline struct kernfs_node * |
442 | kernfs_walk_and_get_ns(struct kernfs_node *parent, const char *path, | |
443 | const void *ns) | |
444 | { return NULL; } | |
ccf73cf3 | 445 | |
324a56e1 TH |
446 | static inline void kernfs_get(struct kernfs_node *kn) { } |
447 | static inline void kernfs_put(struct kernfs_node *kn) { } | |
ccf73cf3 | 448 | |
0c23b225 TH |
449 | static inline struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry) |
450 | { return NULL; } | |
451 | ||
452 | static inline struct kernfs_root *kernfs_root_from_sb(struct super_block *sb) | |
453 | { return NULL; } | |
454 | ||
fb02915f TH |
455 | static inline struct inode * |
456 | kernfs_get_inode(struct super_block *sb, struct kernfs_node *kn) | |
457 | { return NULL; } | |
458 | ||
80b9bbef | 459 | static inline struct kernfs_root * |
d35258ef TH |
460 | kernfs_create_root(struct kernfs_syscall_ops *scops, unsigned int flags, |
461 | void *priv) | |
ba7443bc TH |
462 | { return ERR_PTR(-ENOSYS); } |
463 | ||
464 | static inline void kernfs_destroy_root(struct kernfs_root *root) { } | |
465 | ||
324a56e1 | 466 | static inline struct kernfs_node * |
bb8b9d09 | 467 | kernfs_create_dir_ns(struct kernfs_node *parent, const char *name, |
488dee96 DT |
468 | umode_t mode, kuid_t uid, kgid_t gid, |
469 | void *priv, const void *ns) | |
93b2b8e4 TH |
470 | { return ERR_PTR(-ENOSYS); } |
471 | ||
324a56e1 | 472 | static inline struct kernfs_node * |
2063d608 | 473 | __kernfs_create_file(struct kernfs_node *parent, const char *name, |
488dee96 DT |
474 | umode_t mode, kuid_t uid, kgid_t gid, |
475 | loff_t size, const struct kernfs_ops *ops, | |
dfeb0750 | 476 | void *priv, const void *ns, struct lock_class_key *key) |
496f7394 TH |
477 | { return ERR_PTR(-ENOSYS); } |
478 | ||
324a56e1 TH |
479 | static inline struct kernfs_node * |
480 | kernfs_create_link(struct kernfs_node *parent, const char *name, | |
481 | struct kernfs_node *target) | |
5d0e26bb TH |
482 | { return ERR_PTR(-ENOSYS); } |
483 | ||
d35258ef TH |
484 | static inline void kernfs_activate(struct kernfs_node *kn) { } |
485 | ||
324a56e1 | 486 | static inline void kernfs_remove(struct kernfs_node *kn) { } |
879f40d1 | 487 | |
6b0afc2a TH |
488 | static inline bool kernfs_remove_self(struct kernfs_node *kn) |
489 | { return false; } | |
490 | ||
324a56e1 | 491 | static inline int kernfs_remove_by_name_ns(struct kernfs_node *kn, |
879f40d1 TH |
492 | const char *name, const void *ns) |
493 | { return -ENOSYS; } | |
494 | ||
324a56e1 TH |
495 | static inline int kernfs_rename_ns(struct kernfs_node *kn, |
496 | struct kernfs_node *new_parent, | |
890ece16 TH |
497 | const char *new_name, const void *new_ns) |
498 | { return -ENOSYS; } | |
499 | ||
324a56e1 | 500 | static inline int kernfs_setattr(struct kernfs_node *kn, |
5d60418e TH |
501 | const struct iattr *iattr) |
502 | { return -ENOSYS; } | |
503 | ||
324a56e1 | 504 | static inline void kernfs_notify(struct kernfs_node *kn) { } |
024f6471 | 505 | |
1537ad15 OM |
506 | static inline int kernfs_xattr_get(struct kernfs_node *kn, const char *name, |
507 | void *value, size_t size) | |
b230d5ab OM |
508 | { return -ENOSYS; } |
509 | ||
1537ad15 OM |
510 | static inline int kernfs_xattr_set(struct kernfs_node *kn, const char *name, |
511 | const void *value, size_t size, int flags) | |
b230d5ab OM |
512 | { return -ENOSYS; } |
513 | ||
4b93dc9b TH |
514 | static inline const void *kernfs_super_ns(struct super_block *sb) |
515 | { return NULL; } | |
516 | ||
23bf1b6b DH |
517 | static inline int kernfs_get_tree(struct fs_context *fc) |
518 | { return -ENOSYS; } | |
519 | ||
520 | static inline void kernfs_free_fs_context(struct fs_context *fc) { } | |
4b93dc9b TH |
521 | |
522 | static inline void kernfs_kill_sb(struct super_block *sb) { } | |
523 | ||
524 | static inline void kernfs_init(void) { } | |
525 | ||
ba341d55 | 526 | #endif /* CONFIG_KERNFS */ |
879f40d1 | 527 | |
3abb1d90 TH |
528 | /** |
529 | * kernfs_path - build full path of a given node | |
530 | * @kn: kernfs_node of interest | |
531 | * @buf: buffer to copy @kn's name into | |
532 | * @buflen: size of @buf | |
533 | * | |
8f5be0ec KK |
534 | * If @kn is NULL result will be "(null)". |
535 | * | |
536 | * Returns the length of the full path. If the full length is equal to or | |
537 | * greater than @buflen, @buf contains the truncated path with the trailing | |
538 | * '\0'. On error, -errno is returned. | |
3abb1d90 TH |
539 | */ |
540 | static inline int kernfs_path(struct kernfs_node *kn, char *buf, size_t buflen) | |
541 | { | |
542 | return kernfs_path_from_node(kn, NULL, buf, buflen); | |
543 | } | |
544 | ||
324a56e1 TH |
545 | static inline struct kernfs_node * |
546 | kernfs_find_and_get(struct kernfs_node *kn, const char *name) | |
ccf73cf3 | 547 | { |
324a56e1 | 548 | return kernfs_find_and_get_ns(kn, name, NULL); |
ccf73cf3 TH |
549 | } |
550 | ||
bd96f76a TH |
551 | static inline struct kernfs_node * |
552 | kernfs_walk_and_get(struct kernfs_node *kn, const char *path) | |
553 | { | |
554 | return kernfs_walk_and_get_ns(kn, path, NULL); | |
555 | } | |
556 | ||
324a56e1 | 557 | static inline struct kernfs_node * |
bb8b9d09 TH |
558 | kernfs_create_dir(struct kernfs_node *parent, const char *name, umode_t mode, |
559 | void *priv) | |
93b2b8e4 | 560 | { |
488dee96 DT |
561 | return kernfs_create_dir_ns(parent, name, mode, |
562 | GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, | |
563 | priv, NULL); | |
93b2b8e4 TH |
564 | } |
565 | ||
324a56e1 TH |
566 | static inline struct kernfs_node * |
567 | kernfs_create_file_ns(struct kernfs_node *parent, const char *name, | |
488dee96 DT |
568 | umode_t mode, kuid_t uid, kgid_t gid, |
569 | loff_t size, const struct kernfs_ops *ops, | |
517e64f5 TH |
570 | void *priv, const void *ns) |
571 | { | |
572 | struct lock_class_key *key = NULL; | |
573 | ||
574 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
575 | key = (struct lock_class_key *)&ops->lockdep_key; | |
576 | #endif | |
488dee96 DT |
577 | return __kernfs_create_file(parent, name, mode, uid, gid, |
578 | size, ops, priv, ns, key); | |
517e64f5 TH |
579 | } |
580 | ||
324a56e1 TH |
581 | static inline struct kernfs_node * |
582 | kernfs_create_file(struct kernfs_node *parent, const char *name, umode_t mode, | |
496f7394 TH |
583 | loff_t size, const struct kernfs_ops *ops, void *priv) |
584 | { | |
488dee96 DT |
585 | return kernfs_create_file_ns(parent, name, mode, |
586 | GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, | |
587 | size, ops, priv, NULL); | |
496f7394 TH |
588 | } |
589 | ||
324a56e1 | 590 | static inline int kernfs_remove_by_name(struct kernfs_node *parent, |
879f40d1 TH |
591 | const char *name) |
592 | { | |
593 | return kernfs_remove_by_name_ns(parent, name, NULL); | |
594 | } | |
595 | ||
0c23b225 TH |
596 | static inline int kernfs_rename(struct kernfs_node *kn, |
597 | struct kernfs_node *new_parent, | |
598 | const char *new_name) | |
599 | { | |
600 | return kernfs_rename_ns(kn, new_parent, new_name, NULL); | |
601 | } | |
602 | ||
b8441ed2 | 603 | #endif /* __LINUX_KERNFS_H */ |