2 * file.c - part of debugfs, a tiny little debug file system
4 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
5 * Copyright (C) 2004 IBM Inc.
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
11 * debugfs is for people to use instead of /proc or /sys.
12 * See Documentation/DocBook/filesystems for more details.
16 #include <linux/module.h>
18 #include <linux/seq_file.h>
19 #include <linux/pagemap.h>
20 #include <linux/debugfs.h>
22 #include <linux/slab.h>
23 #include <linux/atomic.h>
24 #include <linux/device.h>
25 #include <linux/srcu.h>
30 struct poll_table_struct
;
32 static ssize_t
default_read_file(struct file
*file
, char __user
*buf
,
33 size_t count
, loff_t
*ppos
)
38 static ssize_t
default_write_file(struct file
*file
, const char __user
*buf
,
39 size_t count
, loff_t
*ppos
)
44 const struct file_operations debugfs_noop_file_operations
= {
45 .read
= default_read_file
,
46 .write
= default_write_file
,
48 .llseek
= noop_llseek
,
52 * debugfs_use_file_start - mark the beginning of file data access
53 * @dentry: the dentry object whose data is being accessed.
54 * @srcu_idx: a pointer to some memory to store a SRCU index in.
56 * Up to a matching call to debugfs_use_file_finish(), any
57 * successive call into the file removing functions debugfs_remove()
58 * and debugfs_remove_recursive() will block. Since associated private
59 * file data may only get freed after a successful return of any of
60 * the removal functions, you may safely access it after a successful
61 * call to debugfs_use_file_start() without worrying about
64 * If -%EIO is returned, the file has already been removed and thus,
65 * it is not safe to access any of its data. If, on the other hand,
66 * it is allowed to access the file data, zero is returned.
68 * Regardless of the return code, any call to
69 * debugfs_use_file_start() must be followed by a matching call
70 * to debugfs_use_file_finish().
72 int debugfs_use_file_start(const struct dentry
*dentry
, int *srcu_idx
)
73 __acquires(&debugfs_srcu
)
75 *srcu_idx
= srcu_read_lock(&debugfs_srcu
);
77 if (d_unlinked(dentry
))
81 EXPORT_SYMBOL_GPL(debugfs_use_file_start
);
84 * debugfs_use_file_finish - mark the end of file data access
85 * @srcu_idx: the SRCU index "created" by a former call to
86 * debugfs_use_file_start().
88 * Allow any ongoing concurrent call into debugfs_remove() or
89 * debugfs_remove_recursive() blocked by a former call to
90 * debugfs_use_file_start() to proceed and return to its caller.
92 void debugfs_use_file_finish(int srcu_idx
) __releases(&debugfs_srcu
)
94 srcu_read_unlock(&debugfs_srcu
, srcu_idx
);
96 EXPORT_SYMBOL_GPL(debugfs_use_file_finish
);
98 #define F_DENTRY(filp) ((filp)->f_path.dentry)
100 #define REAL_FOPS_DEREF(dentry) \
101 ((const struct file_operations *)(dentry)->d_fsdata)
103 static int open_proxy_open(struct inode
*inode
, struct file
*filp
)
105 const struct dentry
*dentry
= F_DENTRY(filp
);
106 const struct file_operations
*real_fops
= NULL
;
109 r
= debugfs_use_file_start(dentry
, &srcu_idx
);
115 real_fops
= REAL_FOPS_DEREF(dentry
);
116 real_fops
= fops_get(real_fops
);
118 /* Huh? Module did not clean up after itself at exit? */
119 WARN(1, "debugfs file owner did not clean up at exit: %pd",
124 replace_fops(filp
, real_fops
);
127 r
= real_fops
->open(inode
, filp
);
131 debugfs_use_file_finish(srcu_idx
);
135 const struct file_operations debugfs_open_proxy_file_operations
= {
136 .open
= open_proxy_open
,
139 #define PROTO(args...) args
140 #define ARGS(args...) args
142 #define FULL_PROXY_FUNC(name, ret_type, filp, proto, args) \
143 static ret_type full_proxy_ ## name(proto) \
145 const struct dentry *dentry = F_DENTRY(filp); \
146 const struct file_operations *real_fops = \
147 REAL_FOPS_DEREF(dentry); \
151 r = debugfs_use_file_start(dentry, &srcu_idx); \
153 r = real_fops->name(args); \
154 debugfs_use_file_finish(srcu_idx); \
158 FULL_PROXY_FUNC(llseek
, loff_t
, filp
,
159 PROTO(struct file
*filp
, loff_t offset
, int whence
),
160 ARGS(filp
, offset
, whence
));
162 FULL_PROXY_FUNC(read
, ssize_t
, filp
,
163 PROTO(struct file
*filp
, char __user
*buf
, size_t size
,
165 ARGS(filp
, buf
, size
, ppos
));
167 FULL_PROXY_FUNC(write
, ssize_t
, filp
,
168 PROTO(struct file
*filp
, const char __user
*buf
, size_t size
,
170 ARGS(filp
, buf
, size
, ppos
));
172 FULL_PROXY_FUNC(unlocked_ioctl
, long, filp
,
173 PROTO(struct file
*filp
, unsigned int cmd
, unsigned long arg
),
174 ARGS(filp
, cmd
, arg
));
176 static unsigned int full_proxy_poll(struct file
*filp
,
177 struct poll_table_struct
*wait
)
179 const struct dentry
*dentry
= F_DENTRY(filp
);
180 const struct file_operations
*real_fops
= REAL_FOPS_DEREF(dentry
);
184 if (debugfs_use_file_start(dentry
, &srcu_idx
)) {
185 debugfs_use_file_finish(srcu_idx
);
189 r
= real_fops
->poll(filp
, wait
);
190 debugfs_use_file_finish(srcu_idx
);
194 static int full_proxy_release(struct inode
*inode
, struct file
*filp
)
196 const struct dentry
*dentry
= F_DENTRY(filp
);
197 const struct file_operations
*real_fops
= REAL_FOPS_DEREF(dentry
);
198 const struct file_operations
*proxy_fops
= filp
->f_op
;
202 * We must not protect this against removal races here: the
203 * original releaser should be called unconditionally in order
204 * not to leak any resources. Releasers must not assume that
205 * ->i_private is still being meaningful here.
207 if (real_fops
->release
)
208 r
= real_fops
->release(inode
, filp
);
210 replace_fops(filp
, d_inode(dentry
)->i_fop
);
211 kfree((void *)proxy_fops
);
216 static void __full_proxy_fops_init(struct file_operations
*proxy_fops
,
217 const struct file_operations
*real_fops
)
219 proxy_fops
->release
= full_proxy_release
;
220 if (real_fops
->llseek
)
221 proxy_fops
->llseek
= full_proxy_llseek
;
223 proxy_fops
->read
= full_proxy_read
;
224 if (real_fops
->write
)
225 proxy_fops
->write
= full_proxy_write
;
227 proxy_fops
->poll
= full_proxy_poll
;
228 if (real_fops
->unlocked_ioctl
)
229 proxy_fops
->unlocked_ioctl
= full_proxy_unlocked_ioctl
;
232 static int full_proxy_open(struct inode
*inode
, struct file
*filp
)
234 const struct dentry
*dentry
= F_DENTRY(filp
);
235 const struct file_operations
*real_fops
= NULL
;
236 struct file_operations
*proxy_fops
= NULL
;
239 r
= debugfs_use_file_start(dentry
, &srcu_idx
);
245 real_fops
= REAL_FOPS_DEREF(dentry
);
246 real_fops
= fops_get(real_fops
);
248 /* Huh? Module did not cleanup after itself at exit? */
249 WARN(1, "debugfs file owner did not clean up at exit: %pd",
255 proxy_fops
= kzalloc(sizeof(*proxy_fops
), GFP_KERNEL
);
260 __full_proxy_fops_init(proxy_fops
, real_fops
);
261 replace_fops(filp
, proxy_fops
);
263 if (real_fops
->open
) {
264 r
= real_fops
->open(inode
, filp
);
266 if (filp
->f_op
!= proxy_fops
) {
267 /* No protection against file removal anymore. */
268 WARN(1, "debugfs file owner replaced proxy fops: %pd",
279 debugfs_use_file_finish(srcu_idx
);
283 const struct file_operations debugfs_full_proxy_file_operations
= {
284 .open
= full_proxy_open
,
287 ssize_t
debugfs_attr_read(struct file
*file
, char __user
*buf
,
288 size_t len
, loff_t
*ppos
)
293 ret
= debugfs_use_file_start(F_DENTRY(file
), &srcu_idx
);
295 ret
= simple_attr_read(file
, buf
, len
, ppos
);
296 debugfs_use_file_finish(srcu_idx
);
299 EXPORT_SYMBOL_GPL(debugfs_attr_read
);
301 ssize_t
debugfs_attr_write(struct file
*file
, const char __user
*buf
,
302 size_t len
, loff_t
*ppos
)
307 ret
= debugfs_use_file_start(F_DENTRY(file
), &srcu_idx
);
309 ret
= simple_attr_write(file
, buf
, len
, ppos
);
310 debugfs_use_file_finish(srcu_idx
);
313 EXPORT_SYMBOL_GPL(debugfs_attr_write
);
315 static struct dentry
*debugfs_create_mode(const char *name
, umode_t mode
,
316 struct dentry
*parent
, void *value
,
317 const struct file_operations
*fops
,
318 const struct file_operations
*fops_ro
,
319 const struct file_operations
*fops_wo
)
321 /* if there are no write bits set, make read only */
322 if (!(mode
& S_IWUGO
))
323 return debugfs_create_file(name
, mode
, parent
, value
, fops_ro
);
324 /* if there are no read bits set, make write only */
325 if (!(mode
& S_IRUGO
))
326 return debugfs_create_file(name
, mode
, parent
, value
, fops_wo
);
328 return debugfs_create_file(name
, mode
, parent
, value
, fops
);
331 static int debugfs_u8_set(void *data
, u64 val
)
336 static int debugfs_u8_get(void *data
, u64
*val
)
341 DEFINE_SIMPLE_ATTRIBUTE(fops_u8
, debugfs_u8_get
, debugfs_u8_set
, "%llu\n");
342 DEFINE_SIMPLE_ATTRIBUTE(fops_u8_ro
, debugfs_u8_get
, NULL
, "%llu\n");
343 DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo
, NULL
, debugfs_u8_set
, "%llu\n");
346 * debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value
347 * @name: a pointer to a string containing the name of the file to create.
348 * @mode: the permission that the file should have
349 * @parent: a pointer to the parent dentry for this file. This should be a
350 * directory dentry if set. If this parameter is %NULL, then the
351 * file will be created in the root of the debugfs filesystem.
352 * @value: a pointer to the variable that the file should read to and write
355 * This function creates a file in debugfs with the given name that
356 * contains the value of the variable @value. If the @mode variable is so
357 * set, it can be read from, and written to.
359 * This function will return a pointer to a dentry if it succeeds. This
360 * pointer must be passed to the debugfs_remove() function when the file is
361 * to be removed (no automatic cleanup happens if your module is unloaded,
362 * you are responsible here.) If an error occurs, %NULL will be returned.
364 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
365 * returned. It is not wise to check for this value, but rather, check for
366 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
369 struct dentry
*debugfs_create_u8(const char *name
, umode_t mode
,
370 struct dentry
*parent
, u8
*value
)
372 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_u8
,
373 &fops_u8_ro
, &fops_u8_wo
);
375 EXPORT_SYMBOL_GPL(debugfs_create_u8
);
377 static int debugfs_u16_set(void *data
, u64 val
)
382 static int debugfs_u16_get(void *data
, u64
*val
)
387 DEFINE_SIMPLE_ATTRIBUTE(fops_u16
, debugfs_u16_get
, debugfs_u16_set
, "%llu\n");
388 DEFINE_SIMPLE_ATTRIBUTE(fops_u16_ro
, debugfs_u16_get
, NULL
, "%llu\n");
389 DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo
, NULL
, debugfs_u16_set
, "%llu\n");
392 * debugfs_create_u16 - create a debugfs file that is used to read and write an unsigned 16-bit value
393 * @name: a pointer to a string containing the name of the file to create.
394 * @mode: the permission that the file should have
395 * @parent: a pointer to the parent dentry for this file. This should be a
396 * directory dentry if set. If this parameter is %NULL, then the
397 * file will be created in the root of the debugfs filesystem.
398 * @value: a pointer to the variable that the file should read to and write
401 * This function creates a file in debugfs with the given name that
402 * contains the value of the variable @value. If the @mode variable is so
403 * set, it can be read from, and written to.
405 * This function will return a pointer to a dentry if it succeeds. This
406 * pointer must be passed to the debugfs_remove() function when the file is
407 * to be removed (no automatic cleanup happens if your module is unloaded,
408 * you are responsible here.) If an error occurs, %NULL will be returned.
410 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
411 * returned. It is not wise to check for this value, but rather, check for
412 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
415 struct dentry
*debugfs_create_u16(const char *name
, umode_t mode
,
416 struct dentry
*parent
, u16
*value
)
418 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_u16
,
419 &fops_u16_ro
, &fops_u16_wo
);
421 EXPORT_SYMBOL_GPL(debugfs_create_u16
);
423 static int debugfs_u32_set(void *data
, u64 val
)
428 static int debugfs_u32_get(void *data
, u64
*val
)
433 DEFINE_SIMPLE_ATTRIBUTE(fops_u32
, debugfs_u32_get
, debugfs_u32_set
, "%llu\n");
434 DEFINE_SIMPLE_ATTRIBUTE(fops_u32_ro
, debugfs_u32_get
, NULL
, "%llu\n");
435 DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo
, NULL
, debugfs_u32_set
, "%llu\n");
438 * debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value
439 * @name: a pointer to a string containing the name of the file to create.
440 * @mode: the permission that the file should have
441 * @parent: a pointer to the parent dentry for this file. This should be a
442 * directory dentry if set. If this parameter is %NULL, then the
443 * file will be created in the root of the debugfs filesystem.
444 * @value: a pointer to the variable that the file should read to and write
447 * This function creates a file in debugfs with the given name that
448 * contains the value of the variable @value. If the @mode variable is so
449 * set, it can be read from, and written to.
451 * This function will return a pointer to a dentry if it succeeds. This
452 * pointer must be passed to the debugfs_remove() function when the file is
453 * to be removed (no automatic cleanup happens if your module is unloaded,
454 * you are responsible here.) If an error occurs, %NULL will be returned.
456 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
457 * returned. It is not wise to check for this value, but rather, check for
458 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
461 struct dentry
*debugfs_create_u32(const char *name
, umode_t mode
,
462 struct dentry
*parent
, u32
*value
)
464 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_u32
,
465 &fops_u32_ro
, &fops_u32_wo
);
467 EXPORT_SYMBOL_GPL(debugfs_create_u32
);
469 static int debugfs_u64_set(void *data
, u64 val
)
475 static int debugfs_u64_get(void *data
, u64
*val
)
480 DEFINE_SIMPLE_ATTRIBUTE(fops_u64
, debugfs_u64_get
, debugfs_u64_set
, "%llu\n");
481 DEFINE_SIMPLE_ATTRIBUTE(fops_u64_ro
, debugfs_u64_get
, NULL
, "%llu\n");
482 DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo
, NULL
, debugfs_u64_set
, "%llu\n");
485 * debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value
486 * @name: a pointer to a string containing the name of the file to create.
487 * @mode: the permission that the file should have
488 * @parent: a pointer to the parent dentry for this file. This should be a
489 * directory dentry if set. If this parameter is %NULL, then the
490 * file will be created in the root of the debugfs filesystem.
491 * @value: a pointer to the variable that the file should read to and write
494 * This function creates a file in debugfs with the given name that
495 * contains the value of the variable @value. If the @mode variable is so
496 * set, it can be read from, and written to.
498 * This function will return a pointer to a dentry if it succeeds. This
499 * pointer must be passed to the debugfs_remove() function when the file is
500 * to be removed (no automatic cleanup happens if your module is unloaded,
501 * you are responsible here.) If an error occurs, %NULL will be returned.
503 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
504 * returned. It is not wise to check for this value, but rather, check for
505 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
508 struct dentry
*debugfs_create_u64(const char *name
, umode_t mode
,
509 struct dentry
*parent
, u64
*value
)
511 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_u64
,
512 &fops_u64_ro
, &fops_u64_wo
);
514 EXPORT_SYMBOL_GPL(debugfs_create_u64
);
516 static int debugfs_ulong_set(void *data
, u64 val
)
518 *(unsigned long *)data
= val
;
522 static int debugfs_ulong_get(void *data
, u64
*val
)
524 *val
= *(unsigned long *)data
;
527 DEFINE_SIMPLE_ATTRIBUTE(fops_ulong
, debugfs_ulong_get
, debugfs_ulong_set
, "%llu\n");
528 DEFINE_SIMPLE_ATTRIBUTE(fops_ulong_ro
, debugfs_ulong_get
, NULL
, "%llu\n");
529 DEFINE_SIMPLE_ATTRIBUTE(fops_ulong_wo
, NULL
, debugfs_ulong_set
, "%llu\n");
532 * debugfs_create_ulong - create a debugfs file that is used to read and write
533 * an unsigned long value.
534 * @name: a pointer to a string containing the name of the file to create.
535 * @mode: the permission that the file should have
536 * @parent: a pointer to the parent dentry for this file. This should be a
537 * directory dentry if set. If this parameter is %NULL, then the
538 * file will be created in the root of the debugfs filesystem.
539 * @value: a pointer to the variable that the file should read to and write
542 * This function creates a file in debugfs with the given name that
543 * contains the value of the variable @value. If the @mode variable is so
544 * set, it can be read from, and written to.
546 * This function will return a pointer to a dentry if it succeeds. This
547 * pointer must be passed to the debugfs_remove() function when the file is
548 * to be removed (no automatic cleanup happens if your module is unloaded,
549 * you are responsible here.) If an error occurs, %NULL will be returned.
551 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
552 * returned. It is not wise to check for this value, but rather, check for
553 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
556 struct dentry
*debugfs_create_ulong(const char *name
, umode_t mode
,
557 struct dentry
*parent
, unsigned long *value
)
559 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_ulong
,
560 &fops_ulong_ro
, &fops_ulong_wo
);
562 EXPORT_SYMBOL_GPL(debugfs_create_ulong
);
564 DEFINE_SIMPLE_ATTRIBUTE(fops_x8
, debugfs_u8_get
, debugfs_u8_set
, "0x%02llx\n");
565 DEFINE_SIMPLE_ATTRIBUTE(fops_x8_ro
, debugfs_u8_get
, NULL
, "0x%02llx\n");
566 DEFINE_SIMPLE_ATTRIBUTE(fops_x8_wo
, NULL
, debugfs_u8_set
, "0x%02llx\n");
568 DEFINE_SIMPLE_ATTRIBUTE(fops_x16
, debugfs_u16_get
, debugfs_u16_set
, "0x%04llx\n");
569 DEFINE_SIMPLE_ATTRIBUTE(fops_x16_ro
, debugfs_u16_get
, NULL
, "0x%04llx\n");
570 DEFINE_SIMPLE_ATTRIBUTE(fops_x16_wo
, NULL
, debugfs_u16_set
, "0x%04llx\n");
572 DEFINE_SIMPLE_ATTRIBUTE(fops_x32
, debugfs_u32_get
, debugfs_u32_set
, "0x%08llx\n");
573 DEFINE_SIMPLE_ATTRIBUTE(fops_x32_ro
, debugfs_u32_get
, NULL
, "0x%08llx\n");
574 DEFINE_SIMPLE_ATTRIBUTE(fops_x32_wo
, NULL
, debugfs_u32_set
, "0x%08llx\n");
576 DEFINE_SIMPLE_ATTRIBUTE(fops_x64
, debugfs_u64_get
, debugfs_u64_set
, "0x%016llx\n");
577 DEFINE_SIMPLE_ATTRIBUTE(fops_x64_ro
, debugfs_u64_get
, NULL
, "0x%016llx\n");
578 DEFINE_SIMPLE_ATTRIBUTE(fops_x64_wo
, NULL
, debugfs_u64_set
, "0x%016llx\n");
581 * 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
583 * These functions are exactly the same as the above functions (but use a hex
584 * output for the decimal challenged). For details look at the above unsigned
589 * debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value
590 * @name: a pointer to a string containing the name of the file to create.
591 * @mode: the permission that the file should have
592 * @parent: a pointer to the parent dentry for this file. This should be a
593 * directory dentry if set. If this parameter is %NULL, then the
594 * file will be created in the root of the debugfs filesystem.
595 * @value: a pointer to the variable that the file should read to and write
598 struct dentry
*debugfs_create_x8(const char *name
, umode_t mode
,
599 struct dentry
*parent
, u8
*value
)
601 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_x8
,
602 &fops_x8_ro
, &fops_x8_wo
);
604 EXPORT_SYMBOL_GPL(debugfs_create_x8
);
607 * debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value
608 * @name: a pointer to a string containing the name of the file to create.
609 * @mode: the permission that the file should have
610 * @parent: a pointer to the parent dentry for this file. This should be a
611 * directory dentry if set. If this parameter is %NULL, then the
612 * file will be created in the root of the debugfs filesystem.
613 * @value: a pointer to the variable that the file should read to and write
616 struct dentry
*debugfs_create_x16(const char *name
, umode_t mode
,
617 struct dentry
*parent
, u16
*value
)
619 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_x16
,
620 &fops_x16_ro
, &fops_x16_wo
);
622 EXPORT_SYMBOL_GPL(debugfs_create_x16
);
625 * debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value
626 * @name: a pointer to a string containing the name of the file to create.
627 * @mode: the permission that the file should have
628 * @parent: a pointer to the parent dentry for this file. This should be a
629 * directory dentry if set. If this parameter is %NULL, then the
630 * file will be created in the root of the debugfs filesystem.
631 * @value: a pointer to the variable that the file should read to and write
634 struct dentry
*debugfs_create_x32(const char *name
, umode_t mode
,
635 struct dentry
*parent
, u32
*value
)
637 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_x32
,
638 &fops_x32_ro
, &fops_x32_wo
);
640 EXPORT_SYMBOL_GPL(debugfs_create_x32
);
643 * debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit value
644 * @name: a pointer to a string containing the name of the file to create.
645 * @mode: the permission that the file should have
646 * @parent: a pointer to the parent dentry for this file. This should be a
647 * directory dentry if set. If this parameter is %NULL, then the
648 * file will be created in the root of the debugfs filesystem.
649 * @value: a pointer to the variable that the file should read to and write
652 struct dentry
*debugfs_create_x64(const char *name
, umode_t mode
,
653 struct dentry
*parent
, u64
*value
)
655 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_x64
,
656 &fops_x64_ro
, &fops_x64_wo
);
658 EXPORT_SYMBOL_GPL(debugfs_create_x64
);
661 static int debugfs_size_t_set(void *data
, u64 val
)
663 *(size_t *)data
= val
;
666 static int debugfs_size_t_get(void *data
, u64
*val
)
668 *val
= *(size_t *)data
;
671 DEFINE_SIMPLE_ATTRIBUTE(fops_size_t
, debugfs_size_t_get
, debugfs_size_t_set
,
672 "%llu\n"); /* %llu and %zu are more or less the same */
673 DEFINE_SIMPLE_ATTRIBUTE(fops_size_t_ro
, debugfs_size_t_get
, NULL
, "%llu\n");
674 DEFINE_SIMPLE_ATTRIBUTE(fops_size_t_wo
, NULL
, debugfs_size_t_set
, "%llu\n");
677 * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value
678 * @name: a pointer to a string containing the name of the file to create.
679 * @mode: the permission that the file should have
680 * @parent: a pointer to the parent dentry for this file. This should be a
681 * directory dentry if set. If this parameter is %NULL, then the
682 * file will be created in the root of the debugfs filesystem.
683 * @value: a pointer to the variable that the file should read to and write
686 struct dentry
*debugfs_create_size_t(const char *name
, umode_t mode
,
687 struct dentry
*parent
, size_t *value
)
689 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_size_t
,
690 &fops_size_t_ro
, &fops_size_t_wo
);
692 EXPORT_SYMBOL_GPL(debugfs_create_size_t
);
694 static int debugfs_atomic_t_set(void *data
, u64 val
)
696 atomic_set((atomic_t
*)data
, val
);
699 static int debugfs_atomic_t_get(void *data
, u64
*val
)
701 *val
= atomic_read((atomic_t
*)data
);
704 DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t
, debugfs_atomic_t_get
,
705 debugfs_atomic_t_set
, "%lld\n");
706 DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_ro
, debugfs_atomic_t_get
, NULL
, "%lld\n");
707 DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_wo
, NULL
, debugfs_atomic_t_set
, "%lld\n");
710 * debugfs_create_atomic_t - create a debugfs file that is used to read and
711 * write an atomic_t value
712 * @name: a pointer to a string containing the name of the file to create.
713 * @mode: the permission that the file should have
714 * @parent: a pointer to the parent dentry for this file. This should be a
715 * directory dentry if set. If this parameter is %NULL, then the
716 * file will be created in the root of the debugfs filesystem.
717 * @value: a pointer to the variable that the file should read to and write
720 struct dentry
*debugfs_create_atomic_t(const char *name
, umode_t mode
,
721 struct dentry
*parent
, atomic_t
*value
)
723 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_atomic_t
,
724 &fops_atomic_t_ro
, &fops_atomic_t_wo
);
726 EXPORT_SYMBOL_GPL(debugfs_create_atomic_t
);
728 ssize_t
debugfs_read_file_bool(struct file
*file
, char __user
*user_buf
,
729 size_t count
, loff_t
*ppos
)
732 bool *val
= file
->private_data
;
740 return simple_read_from_buffer(user_buf
, count
, ppos
, buf
, 2);
742 EXPORT_SYMBOL_GPL(debugfs_read_file_bool
);
744 ssize_t
debugfs_write_file_bool(struct file
*file
, const char __user
*user_buf
,
745 size_t count
, loff_t
*ppos
)
750 bool *val
= file
->private_data
;
752 buf_size
= min(count
, (sizeof(buf
)-1));
753 if (copy_from_user(buf
, user_buf
, buf_size
))
756 buf
[buf_size
] = '\0';
757 if (strtobool(buf
, &bv
) == 0)
762 EXPORT_SYMBOL_GPL(debugfs_write_file_bool
);
764 static const struct file_operations fops_bool
= {
765 .read
= debugfs_read_file_bool
,
766 .write
= debugfs_write_file_bool
,
768 .llseek
= default_llseek
,
771 static const struct file_operations fops_bool_ro
= {
772 .read
= debugfs_read_file_bool
,
774 .llseek
= default_llseek
,
777 static const struct file_operations fops_bool_wo
= {
778 .write
= debugfs_write_file_bool
,
780 .llseek
= default_llseek
,
784 * debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
785 * @name: a pointer to a string containing the name of the file to create.
786 * @mode: the permission that the file should have
787 * @parent: a pointer to the parent dentry for this file. This should be a
788 * directory dentry if set. If this parameter is %NULL, then the
789 * file will be created in the root of the debugfs filesystem.
790 * @value: a pointer to the variable that the file should read to and write
793 * This function creates a file in debugfs with the given name that
794 * contains the value of the variable @value. If the @mode variable is so
795 * set, it can be read from, and written to.
797 * This function will return a pointer to a dentry if it succeeds. This
798 * pointer must be passed to the debugfs_remove() function when the file is
799 * to be removed (no automatic cleanup happens if your module is unloaded,
800 * you are responsible here.) If an error occurs, %NULL will be returned.
802 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
803 * returned. It is not wise to check for this value, but rather, check for
804 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
807 struct dentry
*debugfs_create_bool(const char *name
, umode_t mode
,
808 struct dentry
*parent
, bool *value
)
810 return debugfs_create_mode(name
, mode
, parent
, value
, &fops_bool
,
811 &fops_bool_ro
, &fops_bool_wo
);
813 EXPORT_SYMBOL_GPL(debugfs_create_bool
);
815 static ssize_t
read_file_blob(struct file
*file
, char __user
*user_buf
,
816 size_t count
, loff_t
*ppos
)
818 struct debugfs_blob_wrapper
*blob
= file
->private_data
;
819 return simple_read_from_buffer(user_buf
, count
, ppos
, blob
->data
,
823 static const struct file_operations fops_blob
= {
824 .read
= read_file_blob
,
826 .llseek
= default_llseek
,
830 * debugfs_create_blob - create a debugfs file that is used to read a binary blob
831 * @name: a pointer to a string containing the name of the file to create.
832 * @mode: the permission that the file should have
833 * @parent: a pointer to the parent dentry for this file. This should be a
834 * directory dentry if set. If this parameter is %NULL, then the
835 * file will be created in the root of the debugfs filesystem.
836 * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer
837 * to the blob data and the size of the data.
839 * This function creates a file in debugfs with the given name that exports
840 * @blob->data as a binary blob. If the @mode variable is so set it can be
841 * read from. Writing is not supported.
843 * This function will return a pointer to a dentry if it succeeds. This
844 * pointer must be passed to the debugfs_remove() function when the file is
845 * to be removed (no automatic cleanup happens if your module is unloaded,
846 * you are responsible here.) If an error occurs, %NULL will be returned.
848 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
849 * returned. It is not wise to check for this value, but rather, check for
850 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
853 struct dentry
*debugfs_create_blob(const char *name
, umode_t mode
,
854 struct dentry
*parent
,
855 struct debugfs_blob_wrapper
*blob
)
857 return debugfs_create_file(name
, mode
, parent
, blob
, &fops_blob
);
859 EXPORT_SYMBOL_GPL(debugfs_create_blob
);
866 static size_t u32_format_array(char *buf
, size_t bufsize
,
867 u32
*array
, int array_size
)
871 while (--array_size
>= 0) {
873 char term
= array_size
? ' ' : '\n';
875 len
= snprintf(buf
, bufsize
, "%u%c", *array
++, term
);
884 static int u32_array_open(struct inode
*inode
, struct file
*file
)
886 struct array_data
*data
= inode
->i_private
;
887 int size
, elements
= data
->elements
;
892 * - 10 digits + ' '/'\n' = 11 bytes per number
893 * - terminating NUL character
896 buf
= kmalloc(size
+1, GFP_KERNEL
);
901 file
->private_data
= buf
;
902 u32_format_array(buf
, size
, data
->array
, data
->elements
);
904 return nonseekable_open(inode
, file
);
907 static ssize_t
u32_array_read(struct file
*file
, char __user
*buf
, size_t len
,
910 size_t size
= strlen(file
->private_data
);
912 return simple_read_from_buffer(buf
, len
, ppos
,
913 file
->private_data
, size
);
916 static int u32_array_release(struct inode
*inode
, struct file
*file
)
918 kfree(file
->private_data
);
923 static const struct file_operations u32_array_fops
= {
924 .owner
= THIS_MODULE
,
925 .open
= u32_array_open
,
926 .release
= u32_array_release
,
927 .read
= u32_array_read
,
932 * debugfs_create_u32_array - create a debugfs file that is used to read u32
934 * @name: a pointer to a string containing the name of the file to create.
935 * @mode: the permission that the file should have.
936 * @parent: a pointer to the parent dentry for this file. This should be a
937 * directory dentry if set. If this parameter is %NULL, then the
938 * file will be created in the root of the debugfs filesystem.
939 * @array: u32 array that provides data.
940 * @elements: total number of elements in the array.
942 * This function creates a file in debugfs with the given name that exports
943 * @array as data. If the @mode variable is so set it can be read from.
944 * Writing is not supported. Seek within the file is also not supported.
945 * Once array is created its size can not be changed.
947 * The function returns a pointer to dentry on success. If debugfs is not
948 * enabled in the kernel, the value -%ENODEV will be returned.
950 struct dentry
*debugfs_create_u32_array(const char *name
, umode_t mode
,
951 struct dentry
*parent
,
952 u32
*array
, u32 elements
)
954 struct array_data
*data
= kmalloc(sizeof(*data
), GFP_KERNEL
);
960 data
->elements
= elements
;
962 return debugfs_create_file(name
, mode
, parent
, data
, &u32_array_fops
);
964 EXPORT_SYMBOL_GPL(debugfs_create_u32_array
);
966 #ifdef CONFIG_HAS_IOMEM
969 * The regset32 stuff is used to print 32-bit registers using the
970 * seq_file utilities. We offer printing a register set in an already-opened
971 * sequential file or create a debugfs file that only prints a regset32.
975 * debugfs_print_regs32 - use seq_print to describe a set of registers
976 * @s: the seq_file structure being used to generate output
977 * @regs: an array if struct debugfs_reg32 structures
978 * @nregs: the length of the above array
979 * @base: the base address to be used in reading the registers
980 * @prefix: a string to be prefixed to every output line
982 * This function outputs a text block describing the current values of
983 * some 32-bit hardware registers. It is meant to be used within debugfs
984 * files based on seq_file that need to show registers, intermixed with other
985 * information. The prefix argument may be used to specify a leading string,
986 * because some peripherals have several blocks of identical registers,
987 * for example configuration of dma channels
989 void debugfs_print_regs32(struct seq_file
*s
, const struct debugfs_reg32
*regs
,
990 int nregs
, void __iomem
*base
, char *prefix
)
994 for (i
= 0; i
< nregs
; i
++, regs
++) {
996 seq_printf(s
, "%s", prefix
);
997 seq_printf(s
, "%s = 0x%08x\n", regs
->name
,
998 readl(base
+ regs
->offset
));
999 if (seq_has_overflowed(s
))
1003 EXPORT_SYMBOL_GPL(debugfs_print_regs32
);
1005 static int debugfs_show_regset32(struct seq_file
*s
, void *data
)
1007 struct debugfs_regset32
*regset
= s
->private;
1009 debugfs_print_regs32(s
, regset
->regs
, regset
->nregs
, regset
->base
, "");
1013 static int debugfs_open_regset32(struct inode
*inode
, struct file
*file
)
1015 return single_open(file
, debugfs_show_regset32
, inode
->i_private
);
1018 static const struct file_operations fops_regset32
= {
1019 .open
= debugfs_open_regset32
,
1021 .llseek
= seq_lseek
,
1022 .release
= single_release
,
1026 * debugfs_create_regset32 - create a debugfs file that returns register values
1027 * @name: a pointer to a string containing the name of the file to create.
1028 * @mode: the permission that the file should have
1029 * @parent: a pointer to the parent dentry for this file. This should be a
1030 * directory dentry if set. If this parameter is %NULL, then the
1031 * file will be created in the root of the debugfs filesystem.
1032 * @regset: a pointer to a struct debugfs_regset32, which contains a pointer
1033 * to an array of register definitions, the array size and the base
1034 * address where the register bank is to be found.
1036 * This function creates a file in debugfs with the given name that reports
1037 * the names and values of a set of 32-bit registers. If the @mode variable
1038 * is so set it can be read from. Writing is not supported.
1040 * This function will return a pointer to a dentry if it succeeds. This
1041 * pointer must be passed to the debugfs_remove() function when the file is
1042 * to be removed (no automatic cleanup happens if your module is unloaded,
1043 * you are responsible here.) If an error occurs, %NULL will be returned.
1045 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
1046 * returned. It is not wise to check for this value, but rather, check for
1047 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
1050 struct dentry
*debugfs_create_regset32(const char *name
, umode_t mode
,
1051 struct dentry
*parent
,
1052 struct debugfs_regset32
*regset
)
1054 return debugfs_create_file(name
, mode
, parent
, regset
, &fops_regset32
);
1056 EXPORT_SYMBOL_GPL(debugfs_create_regset32
);
1058 #endif /* CONFIG_HAS_IOMEM */
1060 struct debugfs_devm_entry
{
1061 int (*read
)(struct seq_file
*seq
, void *data
);
1065 static int debugfs_devm_entry_open(struct inode
*inode
, struct file
*f
)
1067 struct debugfs_devm_entry
*entry
= inode
->i_private
;
1069 return single_open(f
, entry
->read
, entry
->dev
);
1072 static const struct file_operations debugfs_devm_entry_ops
= {
1073 .owner
= THIS_MODULE
,
1074 .open
= debugfs_devm_entry_open
,
1075 .release
= single_release
,
1081 * debugfs_create_devm_seqfile - create a debugfs file that is bound to device.
1083 * @dev: device related to this debugfs file.
1084 * @name: name of the debugfs file.
1085 * @parent: a pointer to the parent dentry for this file. This should be a
1086 * directory dentry if set. If this parameter is %NULL, then the
1087 * file will be created in the root of the debugfs filesystem.
1088 * @read_fn: function pointer called to print the seq_file content.
1090 struct dentry
*debugfs_create_devm_seqfile(struct device
*dev
, const char *name
,
1091 struct dentry
*parent
,
1092 int (*read_fn
)(struct seq_file
*s
,
1095 struct debugfs_devm_entry
*entry
;
1098 return ERR_PTR(-ENOENT
);
1100 entry
= devm_kzalloc(dev
, sizeof(*entry
), GFP_KERNEL
);
1102 return ERR_PTR(-ENOMEM
);
1104 entry
->read
= read_fn
;
1107 return debugfs_create_file(name
, S_IRUGO
, parent
, entry
,
1108 &debugfs_devm_entry_ops
);
1110 EXPORT_SYMBOL_GPL(debugfs_create_devm_seqfile
);