1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * file.c - part of debugfs, a tiny little debug file system |
4 | * |
5 | * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com> |
6 | * Copyright (C) 2004 IBM Inc. |
7 | * |
8 | * debugfs is for people to use instead of /proc or /sys. |
9 | * See Documentation/filesystems/ for more details. |
10 | */ |
11 | |
12 | #include <linux/module.h> |
13 | #include <linux/fs.h> |
14 | #include <linux/seq_file.h> |
15 | #include <linux/pagemap.h> |
16 | #include <linux/debugfs.h> |
17 | #include <linux/io.h> |
18 | #include <linux/slab.h> |
19 | #include <linux/atomic.h> |
20 | #include <linux/device.h> |
21 | #include <linux/pm_runtime.h> |
22 | #include <linux/poll.h> |
23 | #include <linux/security.h> |
24 | |
25 | #include "internal.h" |
26 | |
27 | struct poll_table_struct; |
28 | |
29 | static ssize_t default_read_file(struct file *file, char __user *buf, |
30 | size_t count, loff_t *ppos) |
31 | { |
32 | return 0; |
33 | } |
34 | |
35 | static ssize_t default_write_file(struct file *file, const char __user *buf, |
36 | size_t count, loff_t *ppos) |
37 | { |
38 | return count; |
39 | } |
40 | |
41 | const struct file_operations debugfs_noop_file_operations = { |
42 | .read = default_read_file, |
43 | .write = default_write_file, |
44 | .open = simple_open, |
45 | .llseek = noop_llseek, |
46 | }; |
47 | |
48 | #define F_DENTRY(filp) ((filp)->f_path.dentry) |
49 | |
50 | const struct file_operations *debugfs_real_fops(const struct file *filp) |
51 | { |
52 | struct debugfs_fsdata *fsd = F_DENTRY(filp)->d_fsdata; |
53 | |
54 | if ((unsigned long)fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT) { |
55 | /* |
56 | * Urgh, we've been called w/o a protecting |
57 | * debugfs_file_get(). |
58 | */ |
59 | WARN_ON(1); |
60 | return NULL; |
61 | } |
62 | |
63 | return fsd->real_fops; |
64 | } |
65 | EXPORT_SYMBOL_GPL(debugfs_real_fops); |
66 | |
67 | /** |
68 | * debugfs_file_get - mark the beginning of file data access |
69 | * @dentry: the dentry object whose data is being accessed. |
70 | * |
71 | * Up to a matching call to debugfs_file_put(), any successive call |
72 | * into the file removing functions debugfs_remove() and |
73 | * debugfs_remove_recursive() will block. Since associated private |
74 | * file data may only get freed after a successful return of any of |
75 | * the removal functions, you may safely access it after a successful |
76 | * call to debugfs_file_get() without worrying about lifetime issues. |
77 | * |
78 | * If -%EIO is returned, the file has already been removed and thus, |
79 | * it is not safe to access any of its data. If, on the other hand, |
80 | * it is allowed to access the file data, zero is returned. |
81 | */ |
82 | int debugfs_file_get(struct dentry *dentry) |
83 | { |
84 | struct debugfs_fsdata *fsd; |
85 | void *d_fsd; |
86 | |
87 | /* |
88 | * This could only happen if some debugfs user erroneously calls |
89 | * debugfs_file_get() on a dentry that isn't even a file, let |
90 | * them know about it. |
91 | */ |
92 | if (WARN_ON(!d_is_reg(dentry))) |
93 | return -EINVAL; |
94 | |
95 | d_fsd = READ_ONCE(dentry->d_fsdata); |
96 | if (!((unsigned long)d_fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT)) { |
97 | fsd = d_fsd; |
98 | } else { |
99 | fsd = kmalloc(size: sizeof(*fsd), GFP_KERNEL); |
100 | if (!fsd) |
101 | return -ENOMEM; |
102 | |
103 | fsd->real_fops = (void *)((unsigned long)d_fsd & |
104 | ~DEBUGFS_FSDATA_IS_REAL_FOPS_BIT); |
105 | refcount_set(r: &fsd->active_users, n: 1); |
106 | init_completion(x: &fsd->active_users_drained); |
107 | INIT_LIST_HEAD(list: &fsd->cancellations); |
108 | mutex_init(&fsd->cancellations_mtx); |
109 | |
110 | if (cmpxchg(&dentry->d_fsdata, d_fsd, fsd) != d_fsd) { |
111 | mutex_destroy(lock: &fsd->cancellations_mtx); |
112 | kfree(objp: fsd); |
113 | fsd = READ_ONCE(dentry->d_fsdata); |
114 | } |
115 | } |
116 | |
117 | /* |
118 | * In case of a successful cmpxchg() above, this check is |
119 | * strictly necessary and must follow it, see the comment in |
120 | * __debugfs_remove_file(). |
121 | * OTOH, if the cmpxchg() hasn't been executed or wasn't |
122 | * successful, this serves the purpose of not starving |
123 | * removers. |
124 | */ |
125 | if (d_unlinked(dentry)) |
126 | return -EIO; |
127 | |
128 | if (!refcount_inc_not_zero(r: &fsd->active_users)) |
129 | return -EIO; |
130 | |
131 | return 0; |
132 | } |
133 | EXPORT_SYMBOL_GPL(debugfs_file_get); |
134 | |
135 | /** |
136 | * debugfs_file_put - mark the end of file data access |
137 | * @dentry: the dentry object formerly passed to |
138 | * debugfs_file_get(). |
139 | * |
140 | * Allow any ongoing concurrent call into debugfs_remove() or |
141 | * debugfs_remove_recursive() blocked by a former call to |
142 | * debugfs_file_get() to proceed and return to its caller. |
143 | */ |
144 | void debugfs_file_put(struct dentry *dentry) |
145 | { |
146 | struct debugfs_fsdata *fsd = READ_ONCE(dentry->d_fsdata); |
147 | |
148 | if (refcount_dec_and_test(r: &fsd->active_users)) |
149 | complete(&fsd->active_users_drained); |
150 | } |
151 | EXPORT_SYMBOL_GPL(debugfs_file_put); |
152 | |
153 | /** |
154 | * debugfs_enter_cancellation - enter a debugfs cancellation |
155 | * @file: the file being accessed |
156 | * @cancellation: the cancellation object, the cancel callback |
157 | * inside of it must be initialized |
158 | * |
159 | * When a debugfs file is removed it needs to wait for all active |
160 | * operations to complete. However, the operation itself may need |
161 | * to wait for hardware or completion of some asynchronous process |
162 | * or similar. As such, it may need to be cancelled to avoid long |
163 | * waits or even deadlocks. |
164 | * |
165 | * This function can be used inside a debugfs handler that may |
166 | * need to be cancelled. As soon as this function is called, the |
167 | * cancellation's 'cancel' callback may be called, at which point |
168 | * the caller should proceed to call debugfs_leave_cancellation() |
169 | * and leave the debugfs handler function as soon as possible. |
170 | * Note that the 'cancel' callback is only ever called in the |
171 | * context of some kind of debugfs_remove(). |
172 | * |
173 | * This function must be paired with debugfs_leave_cancellation(). |
174 | */ |
175 | void debugfs_enter_cancellation(struct file *file, |
176 | struct debugfs_cancellation *cancellation) |
177 | { |
178 | struct debugfs_fsdata *fsd; |
179 | struct dentry *dentry = F_DENTRY(file); |
180 | |
181 | INIT_LIST_HEAD(list: &cancellation->list); |
182 | |
183 | if (WARN_ON(!d_is_reg(dentry))) |
184 | return; |
185 | |
186 | if (WARN_ON(!cancellation->cancel)) |
187 | return; |
188 | |
189 | fsd = READ_ONCE(dentry->d_fsdata); |
190 | if (WARN_ON(!fsd || |
191 | ((unsigned long)fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT))) |
192 | return; |
193 | |
194 | mutex_lock(&fsd->cancellations_mtx); |
195 | list_add(new: &cancellation->list, head: &fsd->cancellations); |
196 | mutex_unlock(lock: &fsd->cancellations_mtx); |
197 | |
198 | /* if we're already removing wake it up to cancel */ |
199 | if (d_unlinked(dentry)) |
200 | complete(&fsd->active_users_drained); |
201 | } |
202 | EXPORT_SYMBOL_GPL(debugfs_enter_cancellation); |
203 | |
204 | /** |
205 | * debugfs_leave_cancellation - leave cancellation section |
206 | * @file: the file being accessed |
207 | * @cancellation: the cancellation previously registered with |
208 | * debugfs_enter_cancellation() |
209 | * |
210 | * See the documentation of debugfs_enter_cancellation(). |
211 | */ |
212 | void debugfs_leave_cancellation(struct file *file, |
213 | struct debugfs_cancellation *cancellation) |
214 | { |
215 | struct debugfs_fsdata *fsd; |
216 | struct dentry *dentry = F_DENTRY(file); |
217 | |
218 | if (WARN_ON(!d_is_reg(dentry))) |
219 | return; |
220 | |
221 | fsd = READ_ONCE(dentry->d_fsdata); |
222 | if (WARN_ON(!fsd || |
223 | ((unsigned long)fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT))) |
224 | return; |
225 | |
226 | mutex_lock(&fsd->cancellations_mtx); |
227 | if (!list_empty(head: &cancellation->list)) |
228 | list_del(entry: &cancellation->list); |
229 | mutex_unlock(lock: &fsd->cancellations_mtx); |
230 | } |
231 | EXPORT_SYMBOL_GPL(debugfs_leave_cancellation); |
232 | |
233 | /* |
234 | * Only permit access to world-readable files when the kernel is locked down. |
235 | * We also need to exclude any file that has ways to write or alter it as root |
236 | * can bypass the permissions check. |
237 | */ |
238 | static int debugfs_locked_down(struct inode *inode, |
239 | struct file *filp, |
240 | const struct file_operations *real_fops) |
241 | { |
242 | if ((inode->i_mode & 07777 & ~0444) == 0 && |
243 | !(filp->f_mode & FMODE_WRITE) && |
244 | !real_fops->unlocked_ioctl && |
245 | !real_fops->compat_ioctl && |
246 | !real_fops->mmap) |
247 | return 0; |
248 | |
249 | if (security_locked_down(what: LOCKDOWN_DEBUGFS)) |
250 | return -EPERM; |
251 | |
252 | return 0; |
253 | } |
254 | |
255 | static int open_proxy_open(struct inode *inode, struct file *filp) |
256 | { |
257 | struct dentry *dentry = F_DENTRY(filp); |
258 | const struct file_operations *real_fops = NULL; |
259 | int r; |
260 | |
261 | r = debugfs_file_get(dentry); |
262 | if (r) |
263 | return r == -EIO ? -ENOENT : r; |
264 | |
265 | real_fops = debugfs_real_fops(filp); |
266 | |
267 | r = debugfs_locked_down(inode, filp, real_fops); |
268 | if (r) |
269 | goto out; |
270 | |
271 | if (!fops_get(real_fops)) { |
272 | #ifdef CONFIG_MODULES |
273 | if (real_fops->owner && |
274 | real_fops->owner->state == MODULE_STATE_GOING) { |
275 | r = -ENXIO; |
276 | goto out; |
277 | } |
278 | #endif |
279 | |
280 | /* Huh? Module did not clean up after itself at exit? */ |
281 | WARN(1, "debugfs file owner did not clean up at exit: %pd" , |
282 | dentry); |
283 | r = -ENXIO; |
284 | goto out; |
285 | } |
286 | replace_fops(filp, real_fops); |
287 | |
288 | if (real_fops->open) |
289 | r = real_fops->open(inode, filp); |
290 | |
291 | out: |
292 | debugfs_file_put(dentry); |
293 | return r; |
294 | } |
295 | |
296 | const struct file_operations debugfs_open_proxy_file_operations = { |
297 | .open = open_proxy_open, |
298 | }; |
299 | |
300 | #define PROTO(args...) args |
301 | #define ARGS(args...) args |
302 | |
303 | #define FULL_PROXY_FUNC(name, ret_type, filp, proto, args) \ |
304 | static ret_type full_proxy_ ## name(proto) \ |
305 | { \ |
306 | struct dentry *dentry = F_DENTRY(filp); \ |
307 | const struct file_operations *real_fops; \ |
308 | ret_type r; \ |
309 | \ |
310 | r = debugfs_file_get(dentry); \ |
311 | if (unlikely(r)) \ |
312 | return r; \ |
313 | real_fops = debugfs_real_fops(filp); \ |
314 | r = real_fops->name(args); \ |
315 | debugfs_file_put(dentry); \ |
316 | return r; \ |
317 | } |
318 | |
319 | FULL_PROXY_FUNC(llseek, loff_t, filp, |
320 | PROTO(struct file *filp, loff_t offset, int whence), |
321 | ARGS(filp, offset, whence)); |
322 | |
323 | FULL_PROXY_FUNC(read, ssize_t, filp, |
324 | PROTO(struct file *filp, char __user *buf, size_t size, |
325 | loff_t *ppos), |
326 | ARGS(filp, buf, size, ppos)); |
327 | |
328 | FULL_PROXY_FUNC(write, ssize_t, filp, |
329 | PROTO(struct file *filp, const char __user *buf, size_t size, |
330 | loff_t *ppos), |
331 | ARGS(filp, buf, size, ppos)); |
332 | |
333 | FULL_PROXY_FUNC(unlocked_ioctl, long, filp, |
334 | PROTO(struct file *filp, unsigned int cmd, unsigned long arg), |
335 | ARGS(filp, cmd, arg)); |
336 | |
337 | static __poll_t full_proxy_poll(struct file *filp, |
338 | struct poll_table_struct *wait) |
339 | { |
340 | struct dentry *dentry = F_DENTRY(filp); |
341 | __poll_t r = 0; |
342 | const struct file_operations *real_fops; |
343 | |
344 | if (debugfs_file_get(dentry)) |
345 | return EPOLLHUP; |
346 | |
347 | real_fops = debugfs_real_fops(filp); |
348 | r = real_fops->poll(filp, wait); |
349 | debugfs_file_put(dentry); |
350 | return r; |
351 | } |
352 | |
353 | static int full_proxy_release(struct inode *inode, struct file *filp) |
354 | { |
355 | const struct dentry *dentry = F_DENTRY(filp); |
356 | const struct file_operations *real_fops = debugfs_real_fops(filp); |
357 | const struct file_operations *proxy_fops = filp->f_op; |
358 | int r = 0; |
359 | |
360 | /* |
361 | * We must not protect this against removal races here: the |
362 | * original releaser should be called unconditionally in order |
363 | * not to leak any resources. Releasers must not assume that |
364 | * ->i_private is still being meaningful here. |
365 | */ |
366 | if (real_fops->release) |
367 | r = real_fops->release(inode, filp); |
368 | |
369 | replace_fops(filp, d_inode(dentry)->i_fop); |
370 | kfree(objp: proxy_fops); |
371 | fops_put(real_fops); |
372 | return r; |
373 | } |
374 | |
375 | static void __full_proxy_fops_init(struct file_operations *proxy_fops, |
376 | const struct file_operations *real_fops) |
377 | { |
378 | proxy_fops->release = full_proxy_release; |
379 | if (real_fops->llseek) |
380 | proxy_fops->llseek = full_proxy_llseek; |
381 | if (real_fops->read) |
382 | proxy_fops->read = full_proxy_read; |
383 | if (real_fops->write) |
384 | proxy_fops->write = full_proxy_write; |
385 | if (real_fops->poll) |
386 | proxy_fops->poll = full_proxy_poll; |
387 | if (real_fops->unlocked_ioctl) |
388 | proxy_fops->unlocked_ioctl = full_proxy_unlocked_ioctl; |
389 | } |
390 | |
391 | static int full_proxy_open(struct inode *inode, struct file *filp) |
392 | { |
393 | struct dentry *dentry = F_DENTRY(filp); |
394 | const struct file_operations *real_fops = NULL; |
395 | struct file_operations *proxy_fops = NULL; |
396 | int r; |
397 | |
398 | r = debugfs_file_get(dentry); |
399 | if (r) |
400 | return r == -EIO ? -ENOENT : r; |
401 | |
402 | real_fops = debugfs_real_fops(filp); |
403 | |
404 | r = debugfs_locked_down(inode, filp, real_fops); |
405 | if (r) |
406 | goto out; |
407 | |
408 | if (!fops_get(real_fops)) { |
409 | #ifdef CONFIG_MODULES |
410 | if (real_fops->owner && |
411 | real_fops->owner->state == MODULE_STATE_GOING) { |
412 | r = -ENXIO; |
413 | goto out; |
414 | } |
415 | #endif |
416 | |
417 | /* Huh? Module did not cleanup after itself at exit? */ |
418 | WARN(1, "debugfs file owner did not clean up at exit: %pd" , |
419 | dentry); |
420 | r = -ENXIO; |
421 | goto out; |
422 | } |
423 | |
424 | proxy_fops = kzalloc(size: sizeof(*proxy_fops), GFP_KERNEL); |
425 | if (!proxy_fops) { |
426 | r = -ENOMEM; |
427 | goto free_proxy; |
428 | } |
429 | __full_proxy_fops_init(proxy_fops, real_fops); |
430 | replace_fops(filp, proxy_fops); |
431 | |
432 | if (real_fops->open) { |
433 | r = real_fops->open(inode, filp); |
434 | if (r) { |
435 | replace_fops(filp, d_inode(dentry)->i_fop); |
436 | goto free_proxy; |
437 | } else if (filp->f_op != proxy_fops) { |
438 | /* No protection against file removal anymore. */ |
439 | WARN(1, "debugfs file owner replaced proxy fops: %pd" , |
440 | dentry); |
441 | goto free_proxy; |
442 | } |
443 | } |
444 | |
445 | goto out; |
446 | free_proxy: |
447 | kfree(objp: proxy_fops); |
448 | fops_put(real_fops); |
449 | out: |
450 | debugfs_file_put(dentry); |
451 | return r; |
452 | } |
453 | |
454 | const struct file_operations debugfs_full_proxy_file_operations = { |
455 | .open = full_proxy_open, |
456 | }; |
457 | |
458 | ssize_t debugfs_attr_read(struct file *file, char __user *buf, |
459 | size_t len, loff_t *ppos) |
460 | { |
461 | struct dentry *dentry = F_DENTRY(file); |
462 | ssize_t ret; |
463 | |
464 | ret = debugfs_file_get(dentry); |
465 | if (unlikely(ret)) |
466 | return ret; |
467 | ret = simple_attr_read(file, buf, len, ppos); |
468 | debugfs_file_put(dentry); |
469 | return ret; |
470 | } |
471 | EXPORT_SYMBOL_GPL(debugfs_attr_read); |
472 | |
473 | static ssize_t debugfs_attr_write_xsigned(struct file *file, const char __user *buf, |
474 | size_t len, loff_t *ppos, bool is_signed) |
475 | { |
476 | struct dentry *dentry = F_DENTRY(file); |
477 | ssize_t ret; |
478 | |
479 | ret = debugfs_file_get(dentry); |
480 | if (unlikely(ret)) |
481 | return ret; |
482 | if (is_signed) |
483 | ret = simple_attr_write_signed(file, buf, len, ppos); |
484 | else |
485 | ret = simple_attr_write(file, buf, len, ppos); |
486 | debugfs_file_put(dentry); |
487 | return ret; |
488 | } |
489 | |
490 | ssize_t debugfs_attr_write(struct file *file, const char __user *buf, |
491 | size_t len, loff_t *ppos) |
492 | { |
493 | return debugfs_attr_write_xsigned(file, buf, len, ppos, is_signed: false); |
494 | } |
495 | EXPORT_SYMBOL_GPL(debugfs_attr_write); |
496 | |
497 | ssize_t debugfs_attr_write_signed(struct file *file, const char __user *buf, |
498 | size_t len, loff_t *ppos) |
499 | { |
500 | return debugfs_attr_write_xsigned(file, buf, len, ppos, is_signed: true); |
501 | } |
502 | EXPORT_SYMBOL_GPL(debugfs_attr_write_signed); |
503 | |
504 | static struct dentry *debugfs_create_mode_unsafe(const char *name, umode_t mode, |
505 | struct dentry *parent, void *value, |
506 | const struct file_operations *fops, |
507 | const struct file_operations *fops_ro, |
508 | const struct file_operations *fops_wo) |
509 | { |
510 | /* if there are no write bits set, make read only */ |
511 | if (!(mode & S_IWUGO)) |
512 | return debugfs_create_file_unsafe(name, mode, parent, data: value, |
513 | fops: fops_ro); |
514 | /* if there are no read bits set, make write only */ |
515 | if (!(mode & S_IRUGO)) |
516 | return debugfs_create_file_unsafe(name, mode, parent, data: value, |
517 | fops: fops_wo); |
518 | |
519 | return debugfs_create_file_unsafe(name, mode, parent, data: value, fops); |
520 | } |
521 | |
522 | static int debugfs_u8_set(void *data, u64 val) |
523 | { |
524 | *(u8 *)data = val; |
525 | return 0; |
526 | } |
527 | static int debugfs_u8_get(void *data, u64 *val) |
528 | { |
529 | *val = *(u8 *)data; |
530 | return 0; |
531 | } |
532 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n" ); |
533 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u8_ro, debugfs_u8_get, NULL, "%llu\n" ); |
534 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n" ); |
535 | |
536 | /** |
537 | * debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value |
538 | * @name: a pointer to a string containing the name of the file to create. |
539 | * @mode: the permission that the file should have |
540 | * @parent: a pointer to the parent dentry for this file. This should be a |
541 | * directory dentry if set. If this parameter is %NULL, then the |
542 | * file will be created in the root of the debugfs filesystem. |
543 | * @value: a pointer to the variable that the file should read to and write |
544 | * from. |
545 | * |
546 | * This function creates a file in debugfs with the given name that |
547 | * contains the value of the variable @value. If the @mode variable is so |
548 | * set, it can be read from, and written to. |
549 | */ |
550 | void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent, |
551 | u8 *value) |
552 | { |
553 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_u8, |
554 | fops_ro: &fops_u8_ro, fops_wo: &fops_u8_wo); |
555 | } |
556 | EXPORT_SYMBOL_GPL(debugfs_create_u8); |
557 | |
558 | static int debugfs_u16_set(void *data, u64 val) |
559 | { |
560 | *(u16 *)data = val; |
561 | return 0; |
562 | } |
563 | static int debugfs_u16_get(void *data, u64 *val) |
564 | { |
565 | *val = *(u16 *)data; |
566 | return 0; |
567 | } |
568 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n" ); |
569 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u16_ro, debugfs_u16_get, NULL, "%llu\n" ); |
570 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n" ); |
571 | |
572 | /** |
573 | * debugfs_create_u16 - create a debugfs file that is used to read and write an unsigned 16-bit value |
574 | * @name: a pointer to a string containing the name of the file to create. |
575 | * @mode: the permission that the file should have |
576 | * @parent: a pointer to the parent dentry for this file. This should be a |
577 | * directory dentry if set. If this parameter is %NULL, then the |
578 | * file will be created in the root of the debugfs filesystem. |
579 | * @value: a pointer to the variable that the file should read to and write |
580 | * from. |
581 | * |
582 | * This function creates a file in debugfs with the given name that |
583 | * contains the value of the variable @value. If the @mode variable is so |
584 | * set, it can be read from, and written to. |
585 | */ |
586 | void debugfs_create_u16(const char *name, umode_t mode, struct dentry *parent, |
587 | u16 *value) |
588 | { |
589 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_u16, |
590 | fops_ro: &fops_u16_ro, fops_wo: &fops_u16_wo); |
591 | } |
592 | EXPORT_SYMBOL_GPL(debugfs_create_u16); |
593 | |
594 | static int debugfs_u32_set(void *data, u64 val) |
595 | { |
596 | *(u32 *)data = val; |
597 | return 0; |
598 | } |
599 | static int debugfs_u32_get(void *data, u64 *val) |
600 | { |
601 | *val = *(u32 *)data; |
602 | return 0; |
603 | } |
604 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n" ); |
605 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u32_ro, debugfs_u32_get, NULL, "%llu\n" ); |
606 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n" ); |
607 | |
608 | /** |
609 | * debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value |
610 | * @name: a pointer to a string containing the name of the file to create. |
611 | * @mode: the permission that the file should have |
612 | * @parent: a pointer to the parent dentry for this file. This should be a |
613 | * directory dentry if set. If this parameter is %NULL, then the |
614 | * file will be created in the root of the debugfs filesystem. |
615 | * @value: a pointer to the variable that the file should read to and write |
616 | * from. |
617 | * |
618 | * This function creates a file in debugfs with the given name that |
619 | * contains the value of the variable @value. If the @mode variable is so |
620 | * set, it can be read from, and written to. |
621 | */ |
622 | void debugfs_create_u32(const char *name, umode_t mode, struct dentry *parent, |
623 | u32 *value) |
624 | { |
625 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_u32, |
626 | fops_ro: &fops_u32_ro, fops_wo: &fops_u32_wo); |
627 | } |
628 | EXPORT_SYMBOL_GPL(debugfs_create_u32); |
629 | |
630 | static int debugfs_u64_set(void *data, u64 val) |
631 | { |
632 | *(u64 *)data = val; |
633 | return 0; |
634 | } |
635 | |
636 | static int debugfs_u64_get(void *data, u64 *val) |
637 | { |
638 | *val = *(u64 *)data; |
639 | return 0; |
640 | } |
641 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n" ); |
642 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u64_ro, debugfs_u64_get, NULL, "%llu\n" ); |
643 | DEFINE_DEBUGFS_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n" ); |
644 | |
645 | /** |
646 | * debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value |
647 | * @name: a pointer to a string containing the name of the file to create. |
648 | * @mode: the permission that the file should have |
649 | * @parent: a pointer to the parent dentry for this file. This should be a |
650 | * directory dentry if set. If this parameter is %NULL, then the |
651 | * file will be created in the root of the debugfs filesystem. |
652 | * @value: a pointer to the variable that the file should read to and write |
653 | * from. |
654 | * |
655 | * This function creates a file in debugfs with the given name that |
656 | * contains the value of the variable @value. If the @mode variable is so |
657 | * set, it can be read from, and written to. |
658 | */ |
659 | void debugfs_create_u64(const char *name, umode_t mode, struct dentry *parent, |
660 | u64 *value) |
661 | { |
662 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_u64, |
663 | fops_ro: &fops_u64_ro, fops_wo: &fops_u64_wo); |
664 | } |
665 | EXPORT_SYMBOL_GPL(debugfs_create_u64); |
666 | |
667 | static int debugfs_ulong_set(void *data, u64 val) |
668 | { |
669 | *(unsigned long *)data = val; |
670 | return 0; |
671 | } |
672 | |
673 | static int debugfs_ulong_get(void *data, u64 *val) |
674 | { |
675 | *val = *(unsigned long *)data; |
676 | return 0; |
677 | } |
678 | DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong, debugfs_ulong_get, debugfs_ulong_set, |
679 | "%llu\n" ); |
680 | DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_ro, debugfs_ulong_get, NULL, "%llu\n" ); |
681 | DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_wo, NULL, debugfs_ulong_set, "%llu\n" ); |
682 | |
683 | /** |
684 | * debugfs_create_ulong - create a debugfs file that is used to read and write |
685 | * an unsigned long value. |
686 | * @name: a pointer to a string containing the name of the file to create. |
687 | * @mode: the permission that the file should have |
688 | * @parent: a pointer to the parent dentry for this file. This should be a |
689 | * directory dentry if set. If this parameter is %NULL, then the |
690 | * file will be created in the root of the debugfs filesystem. |
691 | * @value: a pointer to the variable that the file should read to and write |
692 | * from. |
693 | * |
694 | * This function creates a file in debugfs with the given name that |
695 | * contains the value of the variable @value. If the @mode variable is so |
696 | * set, it can be read from, and written to. |
697 | */ |
698 | void debugfs_create_ulong(const char *name, umode_t mode, struct dentry *parent, |
699 | unsigned long *value) |
700 | { |
701 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_ulong, |
702 | fops_ro: &fops_ulong_ro, fops_wo: &fops_ulong_wo); |
703 | } |
704 | EXPORT_SYMBOL_GPL(debugfs_create_ulong); |
705 | |
706 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n" ); |
707 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n" ); |
708 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x8_wo, NULL, debugfs_u8_set, "0x%02llx\n" ); |
709 | |
710 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set, |
711 | "0x%04llx\n" ); |
712 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x16_ro, debugfs_u16_get, NULL, "0x%04llx\n" ); |
713 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x16_wo, NULL, debugfs_u16_set, "0x%04llx\n" ); |
714 | |
715 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, |
716 | "0x%08llx\n" ); |
717 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n" ); |
718 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n" ); |
719 | |
720 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, |
721 | "0x%016llx\n" ); |
722 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_ro, debugfs_u64_get, NULL, "0x%016llx\n" ); |
723 | DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_wo, NULL, debugfs_u64_set, "0x%016llx\n" ); |
724 | |
725 | /* |
726 | * debugfs_create_x{8,16,32,64} - create a debugfs file that is used to read and write an unsigned {8,16,32,64}-bit value |
727 | * |
728 | * These functions are exactly the same as the above functions (but use a hex |
729 | * output for the decimal challenged). For details look at the above unsigned |
730 | * decimal functions. |
731 | */ |
732 | |
733 | /** |
734 | * debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value |
735 | * @name: a pointer to a string containing the name of the file to create. |
736 | * @mode: the permission that the file should have |
737 | * @parent: a pointer to the parent dentry for this file. This should be a |
738 | * directory dentry if set. If this parameter is %NULL, then the |
739 | * file will be created in the root of the debugfs filesystem. |
740 | * @value: a pointer to the variable that the file should read to and write |
741 | * from. |
742 | */ |
743 | void debugfs_create_x8(const char *name, umode_t mode, struct dentry *parent, |
744 | u8 *value) |
745 | { |
746 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_x8, |
747 | fops_ro: &fops_x8_ro, fops_wo: &fops_x8_wo); |
748 | } |
749 | EXPORT_SYMBOL_GPL(debugfs_create_x8); |
750 | |
751 | /** |
752 | * debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value |
753 | * @name: a pointer to a string containing the name of the file to create. |
754 | * @mode: the permission that the file should have |
755 | * @parent: a pointer to the parent dentry for this file. This should be a |
756 | * directory dentry if set. If this parameter is %NULL, then the |
757 | * file will be created in the root of the debugfs filesystem. |
758 | * @value: a pointer to the variable that the file should read to and write |
759 | * from. |
760 | */ |
761 | void debugfs_create_x16(const char *name, umode_t mode, struct dentry *parent, |
762 | u16 *value) |
763 | { |
764 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_x16, |
765 | fops_ro: &fops_x16_ro, fops_wo: &fops_x16_wo); |
766 | } |
767 | EXPORT_SYMBOL_GPL(debugfs_create_x16); |
768 | |
769 | /** |
770 | * debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value |
771 | * @name: a pointer to a string containing the name of the file to create. |
772 | * @mode: the permission that the file should have |
773 | * @parent: a pointer to the parent dentry for this file. This should be a |
774 | * directory dentry if set. If this parameter is %NULL, then the |
775 | * file will be created in the root of the debugfs filesystem. |
776 | * @value: a pointer to the variable that the file should read to and write |
777 | * from. |
778 | */ |
779 | void debugfs_create_x32(const char *name, umode_t mode, struct dentry *parent, |
780 | u32 *value) |
781 | { |
782 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_x32, |
783 | fops_ro: &fops_x32_ro, fops_wo: &fops_x32_wo); |
784 | } |
785 | EXPORT_SYMBOL_GPL(debugfs_create_x32); |
786 | |
787 | /** |
788 | * debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit value |
789 | * @name: a pointer to a string containing the name of the file to create. |
790 | * @mode: the permission that the file should have |
791 | * @parent: a pointer to the parent dentry for this file. This should be a |
792 | * directory dentry if set. If this parameter is %NULL, then the |
793 | * file will be created in the root of the debugfs filesystem. |
794 | * @value: a pointer to the variable that the file should read to and write |
795 | * from. |
796 | */ |
797 | void debugfs_create_x64(const char *name, umode_t mode, struct dentry *parent, |
798 | u64 *value) |
799 | { |
800 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_x64, |
801 | fops_ro: &fops_x64_ro, fops_wo: &fops_x64_wo); |
802 | } |
803 | EXPORT_SYMBOL_GPL(debugfs_create_x64); |
804 | |
805 | |
806 | static int debugfs_size_t_set(void *data, u64 val) |
807 | { |
808 | *(size_t *)data = val; |
809 | return 0; |
810 | } |
811 | static int debugfs_size_t_get(void *data, u64 *val) |
812 | { |
813 | *val = *(size_t *)data; |
814 | return 0; |
815 | } |
816 | DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set, |
817 | "%llu\n" ); /* %llu and %zu are more or less the same */ |
818 | DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_ro, debugfs_size_t_get, NULL, "%llu\n" ); |
819 | DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_wo, NULL, debugfs_size_t_set, "%llu\n" ); |
820 | |
821 | /** |
822 | * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value |
823 | * @name: a pointer to a string containing the name of the file to create. |
824 | * @mode: the permission that the file should have |
825 | * @parent: a pointer to the parent dentry for this file. This should be a |
826 | * directory dentry if set. If this parameter is %NULL, then the |
827 | * file will be created in the root of the debugfs filesystem. |
828 | * @value: a pointer to the variable that the file should read to and write |
829 | * from. |
830 | */ |
831 | void debugfs_create_size_t(const char *name, umode_t mode, |
832 | struct dentry *parent, size_t *value) |
833 | { |
834 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_size_t, |
835 | fops_ro: &fops_size_t_ro, fops_wo: &fops_size_t_wo); |
836 | } |
837 | EXPORT_SYMBOL_GPL(debugfs_create_size_t); |
838 | |
839 | static int debugfs_atomic_t_set(void *data, u64 val) |
840 | { |
841 | atomic_set(v: (atomic_t *)data, i: val); |
842 | return 0; |
843 | } |
844 | static int debugfs_atomic_t_get(void *data, u64 *val) |
845 | { |
846 | *val = atomic_read(v: (atomic_t *)data); |
847 | return 0; |
848 | } |
849 | DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(fops_atomic_t, debugfs_atomic_t_get, |
850 | debugfs_atomic_t_set, "%lld\n" ); |
851 | DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(fops_atomic_t_ro, debugfs_atomic_t_get, NULL, |
852 | "%lld\n" ); |
853 | DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(fops_atomic_t_wo, NULL, debugfs_atomic_t_set, |
854 | "%lld\n" ); |
855 | |
856 | /** |
857 | * debugfs_create_atomic_t - create a debugfs file that is used to read and |
858 | * write an atomic_t value |
859 | * @name: a pointer to a string containing the name of the file to create. |
860 | * @mode: the permission that the file should have |
861 | * @parent: a pointer to the parent dentry for this file. This should be a |
862 | * directory dentry if set. If this parameter is %NULL, then the |
863 | * file will be created in the root of the debugfs filesystem. |
864 | * @value: a pointer to the variable that the file should read to and write |
865 | * from. |
866 | */ |
867 | void debugfs_create_atomic_t(const char *name, umode_t mode, |
868 | struct dentry *parent, atomic_t *value) |
869 | { |
870 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_atomic_t, |
871 | fops_ro: &fops_atomic_t_ro, fops_wo: &fops_atomic_t_wo); |
872 | } |
873 | EXPORT_SYMBOL_GPL(debugfs_create_atomic_t); |
874 | |
875 | ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf, |
876 | size_t count, loff_t *ppos) |
877 | { |
878 | char buf[2]; |
879 | bool val; |
880 | int r; |
881 | struct dentry *dentry = F_DENTRY(file); |
882 | |
883 | r = debugfs_file_get(dentry); |
884 | if (unlikely(r)) |
885 | return r; |
886 | val = *(bool *)file->private_data; |
887 | debugfs_file_put(dentry); |
888 | |
889 | if (val) |
890 | buf[0] = 'Y'; |
891 | else |
892 | buf[0] = 'N'; |
893 | buf[1] = '\n'; |
894 | return simple_read_from_buffer(to: user_buf, count, ppos, from: buf, available: 2); |
895 | } |
896 | EXPORT_SYMBOL_GPL(debugfs_read_file_bool); |
897 | |
898 | ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf, |
899 | size_t count, loff_t *ppos) |
900 | { |
901 | bool bv; |
902 | int r; |
903 | bool *val = file->private_data; |
904 | struct dentry *dentry = F_DENTRY(file); |
905 | |
906 | r = kstrtobool_from_user(s: user_buf, count, res: &bv); |
907 | if (!r) { |
908 | r = debugfs_file_get(dentry); |
909 | if (unlikely(r)) |
910 | return r; |
911 | *val = bv; |
912 | debugfs_file_put(dentry); |
913 | } |
914 | |
915 | return count; |
916 | } |
917 | EXPORT_SYMBOL_GPL(debugfs_write_file_bool); |
918 | |
919 | static const struct file_operations fops_bool = { |
920 | .read = debugfs_read_file_bool, |
921 | .write = debugfs_write_file_bool, |
922 | .open = simple_open, |
923 | .llseek = default_llseek, |
924 | }; |
925 | |
926 | static const struct file_operations fops_bool_ro = { |
927 | .read = debugfs_read_file_bool, |
928 | .open = simple_open, |
929 | .llseek = default_llseek, |
930 | }; |
931 | |
932 | static const struct file_operations fops_bool_wo = { |
933 | .write = debugfs_write_file_bool, |
934 | .open = simple_open, |
935 | .llseek = default_llseek, |
936 | }; |
937 | |
938 | /** |
939 | * debugfs_create_bool - create a debugfs file that is used to read and write a boolean value |
940 | * @name: a pointer to a string containing the name of the file to create. |
941 | * @mode: the permission that the file should have |
942 | * @parent: a pointer to the parent dentry for this file. This should be a |
943 | * directory dentry if set. If this parameter is %NULL, then the |
944 | * file will be created in the root of the debugfs filesystem. |
945 | * @value: a pointer to the variable that the file should read to and write |
946 | * from. |
947 | * |
948 | * This function creates a file in debugfs with the given name that |
949 | * contains the value of the variable @value. If the @mode variable is so |
950 | * set, it can be read from, and written to. |
951 | */ |
952 | void debugfs_create_bool(const char *name, umode_t mode, struct dentry *parent, |
953 | bool *value) |
954 | { |
955 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_bool, |
956 | fops_ro: &fops_bool_ro, fops_wo: &fops_bool_wo); |
957 | } |
958 | EXPORT_SYMBOL_GPL(debugfs_create_bool); |
959 | |
960 | ssize_t debugfs_read_file_str(struct file *file, char __user *user_buf, |
961 | size_t count, loff_t *ppos) |
962 | { |
963 | struct dentry *dentry = F_DENTRY(file); |
964 | char *str, *copy = NULL; |
965 | int copy_len, len; |
966 | ssize_t ret; |
967 | |
968 | ret = debugfs_file_get(dentry); |
969 | if (unlikely(ret)) |
970 | return ret; |
971 | |
972 | str = *(char **)file->private_data; |
973 | len = strlen(str) + 1; |
974 | copy = kmalloc(size: len, GFP_KERNEL); |
975 | if (!copy) { |
976 | debugfs_file_put(dentry); |
977 | return -ENOMEM; |
978 | } |
979 | |
980 | copy_len = strscpy(copy, str, len); |
981 | debugfs_file_put(dentry); |
982 | if (copy_len < 0) { |
983 | kfree(objp: copy); |
984 | return copy_len; |
985 | } |
986 | |
987 | copy[copy_len] = '\n'; |
988 | |
989 | ret = simple_read_from_buffer(to: user_buf, count, ppos, from: copy, available: len); |
990 | kfree(objp: copy); |
991 | |
992 | return ret; |
993 | } |
994 | EXPORT_SYMBOL_GPL(debugfs_create_str); |
995 | |
996 | static ssize_t debugfs_write_file_str(struct file *file, const char __user *user_buf, |
997 | size_t count, loff_t *ppos) |
998 | { |
999 | struct dentry *dentry = F_DENTRY(file); |
1000 | char *old, *new = NULL; |
1001 | int pos = *ppos; |
1002 | int r; |
1003 | |
1004 | r = debugfs_file_get(dentry); |
1005 | if (unlikely(r)) |
1006 | return r; |
1007 | |
1008 | old = *(char **)file->private_data; |
1009 | |
1010 | /* only allow strict concatenation */ |
1011 | r = -EINVAL; |
1012 | if (pos && pos != strlen(old)) |
1013 | goto error; |
1014 | |
1015 | r = -E2BIG; |
1016 | if (pos + count + 1 > PAGE_SIZE) |
1017 | goto error; |
1018 | |
1019 | r = -ENOMEM; |
1020 | new = kmalloc(size: pos + count + 1, GFP_KERNEL); |
1021 | if (!new) |
1022 | goto error; |
1023 | |
1024 | if (pos) |
1025 | memcpy(new, old, pos); |
1026 | |
1027 | r = -EFAULT; |
1028 | if (copy_from_user(to: new + pos, from: user_buf, n: count)) |
1029 | goto error; |
1030 | |
1031 | new[pos + count] = '\0'; |
1032 | strim(new); |
1033 | |
1034 | rcu_assign_pointer(*(char __rcu **)file->private_data, new); |
1035 | synchronize_rcu(); |
1036 | kfree(objp: old); |
1037 | |
1038 | debugfs_file_put(dentry); |
1039 | return count; |
1040 | |
1041 | error: |
1042 | kfree(objp: new); |
1043 | debugfs_file_put(dentry); |
1044 | return r; |
1045 | } |
1046 | |
1047 | static const struct file_operations fops_str = { |
1048 | .read = debugfs_read_file_str, |
1049 | .write = debugfs_write_file_str, |
1050 | .open = simple_open, |
1051 | .llseek = default_llseek, |
1052 | }; |
1053 | |
1054 | static const struct file_operations fops_str_ro = { |
1055 | .read = debugfs_read_file_str, |
1056 | .open = simple_open, |
1057 | .llseek = default_llseek, |
1058 | }; |
1059 | |
1060 | static const struct file_operations fops_str_wo = { |
1061 | .write = debugfs_write_file_str, |
1062 | .open = simple_open, |
1063 | .llseek = default_llseek, |
1064 | }; |
1065 | |
1066 | /** |
1067 | * debugfs_create_str - create a debugfs file that is used to read and write a string value |
1068 | * @name: a pointer to a string containing the name of the file to create. |
1069 | * @mode: the permission that the file should have |
1070 | * @parent: a pointer to the parent dentry for this file. This should be a |
1071 | * directory dentry if set. If this parameter is %NULL, then the |
1072 | * file will be created in the root of the debugfs filesystem. |
1073 | * @value: a pointer to the variable that the file should read to and write |
1074 | * from. |
1075 | * |
1076 | * This function creates a file in debugfs with the given name that |
1077 | * contains the value of the variable @value. If the @mode variable is so |
1078 | * set, it can be read from, and written to. |
1079 | */ |
1080 | void debugfs_create_str(const char *name, umode_t mode, |
1081 | struct dentry *parent, char **value) |
1082 | { |
1083 | debugfs_create_mode_unsafe(name, mode, parent, value, fops: &fops_str, |
1084 | fops_ro: &fops_str_ro, fops_wo: &fops_str_wo); |
1085 | } |
1086 | |
1087 | static ssize_t read_file_blob(struct file *file, char __user *user_buf, |
1088 | size_t count, loff_t *ppos) |
1089 | { |
1090 | struct debugfs_blob_wrapper *blob = file->private_data; |
1091 | struct dentry *dentry = F_DENTRY(file); |
1092 | ssize_t r; |
1093 | |
1094 | r = debugfs_file_get(dentry); |
1095 | if (unlikely(r)) |
1096 | return r; |
1097 | r = simple_read_from_buffer(to: user_buf, count, ppos, from: blob->data, |
1098 | available: blob->size); |
1099 | debugfs_file_put(dentry); |
1100 | return r; |
1101 | } |
1102 | |
1103 | static ssize_t write_file_blob(struct file *file, const char __user *user_buf, |
1104 | size_t count, loff_t *ppos) |
1105 | { |
1106 | struct debugfs_blob_wrapper *blob = file->private_data; |
1107 | struct dentry *dentry = F_DENTRY(file); |
1108 | ssize_t r; |
1109 | |
1110 | r = debugfs_file_get(dentry); |
1111 | if (unlikely(r)) |
1112 | return r; |
1113 | r = simple_write_to_buffer(to: blob->data, available: blob->size, ppos, from: user_buf, |
1114 | count); |
1115 | |
1116 | debugfs_file_put(dentry); |
1117 | return r; |
1118 | } |
1119 | |
1120 | static const struct file_operations fops_blob = { |
1121 | .read = read_file_blob, |
1122 | .write = write_file_blob, |
1123 | .open = simple_open, |
1124 | .llseek = default_llseek, |
1125 | }; |
1126 | |
1127 | /** |
1128 | * debugfs_create_blob - create a debugfs file that is used to read and write |
1129 | * a binary blob |
1130 | * @name: a pointer to a string containing the name of the file to create. |
1131 | * @mode: the permission that the file should have |
1132 | * @parent: a pointer to the parent dentry for this file. This should be a |
1133 | * directory dentry if set. If this parameter is %NULL, then the |
1134 | * file will be created in the root of the debugfs filesystem. |
1135 | * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer |
1136 | * to the blob data and the size of the data. |
1137 | * |
1138 | * This function creates a file in debugfs with the given name that exports |
1139 | * @blob->data as a binary blob. If the @mode variable is so set it can be |
1140 | * read from and written to. |
1141 | * |
1142 | * This function will return a pointer to a dentry if it succeeds. This |
1143 | * pointer must be passed to the debugfs_remove() function when the file is |
1144 | * to be removed (no automatic cleanup happens if your module is unloaded, |
1145 | * you are responsible here.) If an error occurs, ERR_PTR(-ERROR) will be |
1146 | * returned. |
1147 | * |
1148 | * If debugfs is not enabled in the kernel, the value ERR_PTR(-ENODEV) will |
1149 | * be returned. |
1150 | */ |
1151 | struct dentry *debugfs_create_blob(const char *name, umode_t mode, |
1152 | struct dentry *parent, |
1153 | struct debugfs_blob_wrapper *blob) |
1154 | { |
1155 | return debugfs_create_file_unsafe(name, mode: mode & 0644, parent, data: blob, fops: &fops_blob); |
1156 | } |
1157 | EXPORT_SYMBOL_GPL(debugfs_create_blob); |
1158 | |
1159 | static size_t u32_format_array(char *buf, size_t bufsize, |
1160 | u32 *array, int array_size) |
1161 | { |
1162 | size_t ret = 0; |
1163 | |
1164 | while (--array_size >= 0) { |
1165 | size_t len; |
1166 | char term = array_size ? ' ' : '\n'; |
1167 | |
1168 | len = snprintf(buf, size: bufsize, fmt: "%u%c" , *array++, term); |
1169 | ret += len; |
1170 | |
1171 | buf += len; |
1172 | bufsize -= len; |
1173 | } |
1174 | return ret; |
1175 | } |
1176 | |
1177 | static int u32_array_open(struct inode *inode, struct file *file) |
1178 | { |
1179 | struct debugfs_u32_array *data = inode->i_private; |
1180 | int size, elements = data->n_elements; |
1181 | char *buf; |
1182 | |
1183 | /* |
1184 | * Max size: |
1185 | * - 10 digits + ' '/'\n' = 11 bytes per number |
1186 | * - terminating NUL character |
1187 | */ |
1188 | size = elements*11; |
1189 | buf = kmalloc(size: size+1, GFP_KERNEL); |
1190 | if (!buf) |
1191 | return -ENOMEM; |
1192 | buf[size] = 0; |
1193 | |
1194 | file->private_data = buf; |
1195 | u32_format_array(buf, bufsize: size, array: data->array, array_size: data->n_elements); |
1196 | |
1197 | return nonseekable_open(inode, filp: file); |
1198 | } |
1199 | |
1200 | static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len, |
1201 | loff_t *ppos) |
1202 | { |
1203 | size_t size = strlen(file->private_data); |
1204 | |
1205 | return simple_read_from_buffer(to: buf, count: len, ppos, |
1206 | from: file->private_data, available: size); |
1207 | } |
1208 | |
1209 | static int u32_array_release(struct inode *inode, struct file *file) |
1210 | { |
1211 | kfree(objp: file->private_data); |
1212 | |
1213 | return 0; |
1214 | } |
1215 | |
1216 | static const struct file_operations u32_array_fops = { |
1217 | .owner = THIS_MODULE, |
1218 | .open = u32_array_open, |
1219 | .release = u32_array_release, |
1220 | .read = u32_array_read, |
1221 | .llseek = no_llseek, |
1222 | }; |
1223 | |
1224 | /** |
1225 | * debugfs_create_u32_array - create a debugfs file that is used to read u32 |
1226 | * array. |
1227 | * @name: a pointer to a string containing the name of the file to create. |
1228 | * @mode: the permission that the file should have. |
1229 | * @parent: a pointer to the parent dentry for this file. This should be a |
1230 | * directory dentry if set. If this parameter is %NULL, then the |
1231 | * file will be created in the root of the debugfs filesystem. |
1232 | * @array: wrapper struct containing data pointer and size of the array. |
1233 | * |
1234 | * This function creates a file in debugfs with the given name that exports |
1235 | * @array as data. If the @mode variable is so set it can be read from. |
1236 | * Writing is not supported. Seek within the file is also not supported. |
1237 | * Once array is created its size can not be changed. |
1238 | */ |
1239 | void debugfs_create_u32_array(const char *name, umode_t mode, |
1240 | struct dentry *parent, |
1241 | struct debugfs_u32_array *array) |
1242 | { |
1243 | debugfs_create_file_unsafe(name, mode, parent, data: array, fops: &u32_array_fops); |
1244 | } |
1245 | EXPORT_SYMBOL_GPL(debugfs_create_u32_array); |
1246 | |
1247 | #ifdef CONFIG_HAS_IOMEM |
1248 | |
1249 | /* |
1250 | * The regset32 stuff is used to print 32-bit registers using the |
1251 | * seq_file utilities. We offer printing a register set in an already-opened |
1252 | * sequential file or create a debugfs file that only prints a regset32. |
1253 | */ |
1254 | |
1255 | /** |
1256 | * debugfs_print_regs32 - use seq_print to describe a set of registers |
1257 | * @s: the seq_file structure being used to generate output |
1258 | * @regs: an array if struct debugfs_reg32 structures |
1259 | * @nregs: the length of the above array |
1260 | * @base: the base address to be used in reading the registers |
1261 | * @prefix: a string to be prefixed to every output line |
1262 | * |
1263 | * This function outputs a text block describing the current values of |
1264 | * some 32-bit hardware registers. It is meant to be used within debugfs |
1265 | * files based on seq_file that need to show registers, intermixed with other |
1266 | * information. The prefix argument may be used to specify a leading string, |
1267 | * because some peripherals have several blocks of identical registers, |
1268 | * for example configuration of dma channels |
1269 | */ |
1270 | void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs, |
1271 | int nregs, void __iomem *base, char *prefix) |
1272 | { |
1273 | int i; |
1274 | |
1275 | for (i = 0; i < nregs; i++, regs++) { |
1276 | if (prefix) |
1277 | seq_printf(m: s, fmt: "%s" , prefix); |
1278 | seq_printf(m: s, fmt: "%s = 0x%08x\n" , regs->name, |
1279 | readl(addr: base + regs->offset)); |
1280 | if (seq_has_overflowed(m: s)) |
1281 | break; |
1282 | } |
1283 | } |
1284 | EXPORT_SYMBOL_GPL(debugfs_print_regs32); |
1285 | |
1286 | static int debugfs_regset32_show(struct seq_file *s, void *data) |
1287 | { |
1288 | struct debugfs_regset32 *regset = s->private; |
1289 | |
1290 | if (regset->dev) |
1291 | pm_runtime_get_sync(dev: regset->dev); |
1292 | |
1293 | debugfs_print_regs32(s, regset->regs, regset->nregs, regset->base, "" ); |
1294 | |
1295 | if (regset->dev) |
1296 | pm_runtime_put(dev: regset->dev); |
1297 | |
1298 | return 0; |
1299 | } |
1300 | |
1301 | DEFINE_SHOW_ATTRIBUTE(debugfs_regset32); |
1302 | |
1303 | /** |
1304 | * debugfs_create_regset32 - create a debugfs file that returns register values |
1305 | * @name: a pointer to a string containing the name of the file to create. |
1306 | * @mode: the permission that the file should have |
1307 | * @parent: a pointer to the parent dentry for this file. This should be a |
1308 | * directory dentry if set. If this parameter is %NULL, then the |
1309 | * file will be created in the root of the debugfs filesystem. |
1310 | * @regset: a pointer to a struct debugfs_regset32, which contains a pointer |
1311 | * to an array of register definitions, the array size and the base |
1312 | * address where the register bank is to be found. |
1313 | * |
1314 | * This function creates a file in debugfs with the given name that reports |
1315 | * the names and values of a set of 32-bit registers. If the @mode variable |
1316 | * is so set it can be read from. Writing is not supported. |
1317 | */ |
1318 | void debugfs_create_regset32(const char *name, umode_t mode, |
1319 | struct dentry *parent, |
1320 | struct debugfs_regset32 *regset) |
1321 | { |
1322 | debugfs_create_file(name, mode, parent, data: regset, fops: &debugfs_regset32_fops); |
1323 | } |
1324 | EXPORT_SYMBOL_GPL(debugfs_create_regset32); |
1325 | |
1326 | #endif /* CONFIG_HAS_IOMEM */ |
1327 | |
1328 | struct debugfs_devm_entry { |
1329 | int (*read)(struct seq_file *seq, void *data); |
1330 | struct device *dev; |
1331 | }; |
1332 | |
1333 | static int debugfs_devm_entry_open(struct inode *inode, struct file *f) |
1334 | { |
1335 | struct debugfs_devm_entry *entry = inode->i_private; |
1336 | |
1337 | return single_open(f, entry->read, entry->dev); |
1338 | } |
1339 | |
1340 | static const struct file_operations debugfs_devm_entry_ops = { |
1341 | .owner = THIS_MODULE, |
1342 | .open = debugfs_devm_entry_open, |
1343 | .release = single_release, |
1344 | .read = seq_read, |
1345 | .llseek = seq_lseek |
1346 | }; |
1347 | |
1348 | /** |
1349 | * debugfs_create_devm_seqfile - create a debugfs file that is bound to device. |
1350 | * |
1351 | * @dev: device related to this debugfs file. |
1352 | * @name: name of the debugfs file. |
1353 | * @parent: a pointer to the parent dentry for this file. This should be a |
1354 | * directory dentry if set. If this parameter is %NULL, then the |
1355 | * file will be created in the root of the debugfs filesystem. |
1356 | * @read_fn: function pointer called to print the seq_file content. |
1357 | */ |
1358 | void debugfs_create_devm_seqfile(struct device *dev, const char *name, |
1359 | struct dentry *parent, |
1360 | int (*read_fn)(struct seq_file *s, void *data)) |
1361 | { |
1362 | struct debugfs_devm_entry *entry; |
1363 | |
1364 | if (IS_ERR(ptr: parent)) |
1365 | return; |
1366 | |
1367 | entry = devm_kzalloc(dev, size: sizeof(*entry), GFP_KERNEL); |
1368 | if (!entry) |
1369 | return; |
1370 | |
1371 | entry->read = read_fn; |
1372 | entry->dev = dev; |
1373 | |
1374 | debugfs_create_file(name, S_IRUGO, parent, data: entry, |
1375 | fops: &debugfs_devm_entry_ops); |
1376 | } |
1377 | EXPORT_SYMBOL_GPL(debugfs_create_devm_seqfile); |
1378 | |