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