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/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 static int open_proxy_open(struct inode
*inode
, struct file
*filp
)
102 const struct dentry
*dentry
= F_DENTRY(filp
);
103 const struct file_operations
*real_fops
= NULL
;
106 r
= debugfs_use_file_start(dentry
, &srcu_idx
);
112 real_fops
= debugfs_real_fops(filp
);
113 real_fops
= fops_get(real_fops
);
115 /* Huh? Module did not clean up after itself at exit? */
116 WARN(1, "debugfs file owner did not clean up at exit: %pd",
121 replace_fops(filp
, real_fops
);
124 r
= real_fops
->open(inode
, filp
);
127 debugfs_use_file_finish(srcu_idx
);
131 const struct file_operations debugfs_open_proxy_file_operations
= {
132 .open
= open_proxy_open
,
135 #define PROTO(args...) args
136 #define ARGS(args...) args
138 #define FULL_PROXY_FUNC(name, ret_type, filp, proto, args) \
139 static ret_type full_proxy_ ## name(proto) \
141 const struct dentry *dentry = F_DENTRY(filp); \
142 const struct file_operations *real_fops = \
143 debugfs_real_fops(filp); \
147 r = debugfs_use_file_start(dentry, &srcu_idx); \
149 r = real_fops->name(args); \
150 debugfs_use_file_finish(srcu_idx); \
154 FULL_PROXY_FUNC(llseek
, loff_t
, filp
,
155 PROTO(struct file
*filp
, loff_t offset
, int whence
),
156 ARGS(filp
, offset
, whence
));
158 FULL_PROXY_FUNC(read
, ssize_t
, filp
,
159 PROTO(struct file
*filp
, char __user
*buf
, size_t size
,
161 ARGS(filp
, buf
, size
, ppos
));
163 FULL_PROXY_FUNC(write
, ssize_t
, filp
,
164 PROTO(struct file
*filp
, const char __user
*buf
, size_t size
,
166 ARGS(filp
, buf
, size
, ppos
));
168 FULL_PROXY_FUNC(unlocked_ioctl
, long, filp
,
169 PROTO(struct file
*filp
, unsigned int cmd
, unsigned long arg
),
170 ARGS(filp
, cmd
, arg
));
172 static unsigned int full_proxy_poll(struct file
*filp
,
173 struct poll_table_struct
*wait
)
175 const struct dentry
*dentry
= F_DENTRY(filp
);
176 const struct file_operations
*real_fops
= debugfs_real_fops(filp
);
180 if (debugfs_use_file_start(dentry
, &srcu_idx
)) {
181 debugfs_use_file_finish(srcu_idx
);
185 r
= real_fops
->poll(filp
, wait
);
186 debugfs_use_file_finish(srcu_idx
);
190 static int full_proxy_release(struct inode
*inode
, struct file
*filp
)
192 const struct dentry
*dentry
= F_DENTRY(filp
);
193 const struct file_operations
*real_fops
= debugfs_real_fops(filp
);
194 const struct file_operations
*proxy_fops
= filp
->f_op
;
198 * We must not protect this against removal races here: the
199 * original releaser should be called unconditionally in order
200 * not to leak any resources. Releasers must not assume that
201 * ->i_private is still being meaningful here.
203 if (real_fops
->release
)
204 r
= real_fops
->release(inode
, filp
);
206 replace_fops(filp
, d_inode(dentry
)->i_fop
);
207 kfree((void *)proxy_fops
);
212 static void __full_proxy_fops_init(struct file_operations
*proxy_fops
,
213 const struct file_operations
*real_fops
)
215 proxy_fops
->release
= full_proxy_release
;
216 if (real_fops
->llseek
)
217 proxy_fops
->llseek
= full_proxy_llseek
;
219 proxy_fops
->read
= full_proxy_read
;
220 if (real_fops
->write
)
221 proxy_fops
->write
= full_proxy_write
;
223 proxy_fops
->poll
= full_proxy_poll
;
224 if (real_fops
->unlocked_ioctl
)
225 proxy_fops
->unlocked_ioctl
= full_proxy_unlocked_ioctl
;
228 static int full_proxy_open(struct inode
*inode
, struct file
*filp
)
230 const struct dentry
*dentry
= F_DENTRY(filp
);
231 const struct file_operations
*real_fops
= NULL
;
232 struct file_operations
*proxy_fops
= NULL
;
235 r
= debugfs_use_file_start(dentry
, &srcu_idx
);
241 real_fops
= debugfs_real_fops(filp
);
242 real_fops
= fops_get(real_fops
);
244 /* Huh? Module did not cleanup after itself at exit? */
245 WARN(1, "debugfs file owner did not clean up at exit: %pd",
251 proxy_fops
= kzalloc(sizeof(*proxy_fops
), GFP_KERNEL
);
256 __full_proxy_fops_init(proxy_fops
, real_fops
);
257 replace_fops(filp
, proxy_fops
);
259 if (real_fops
->open
) {
260 r
= real_fops
->open(inode
, filp
);
262 replace_fops(filp
, d_inode(dentry
)->i_fop
);
264 } else if (filp
->f_op
!= proxy_fops
) {
265 /* No protection against file removal anymore. */
266 WARN(1, "debugfs file owner replaced proxy fops: %pd",
277 debugfs_use_file_finish(srcu_idx
);
281 const struct file_operations debugfs_full_proxy_file_operations
= {
282 .open
= full_proxy_open
,
285 ssize_t
debugfs_attr_read(struct file
*file
, char __user
*buf
,
286 size_t len
, loff_t
*ppos
)
291 ret
= debugfs_use_file_start(F_DENTRY(file
), &srcu_idx
);
293 ret
= simple_attr_read(file
, buf
, len
, ppos
);
294 debugfs_use_file_finish(srcu_idx
);
297 EXPORT_SYMBOL_GPL(debugfs_attr_read
);
299 ssize_t
debugfs_attr_write(struct file
*file
, const char __user
*buf
,
300 size_t len
, loff_t
*ppos
)
305 ret
= debugfs_use_file_start(F_DENTRY(file
), &srcu_idx
);
307 ret
= simple_attr_write(file
, buf
, len
, ppos
);
308 debugfs_use_file_finish(srcu_idx
);
311 EXPORT_SYMBOL_GPL(debugfs_attr_write
);
313 static struct dentry
*debugfs_create_mode_unsafe(const char *name
, umode_t mode
,
314 struct dentry
*parent
, void *value
,
315 const struct file_operations
*fops
,
316 const struct file_operations
*fops_ro
,
317 const struct file_operations
*fops_wo
)
319 /* if there are no write bits set, make read only */
320 if (!(mode
& S_IWUGO
))
321 return debugfs_create_file_unsafe(name
, mode
, parent
, value
,
323 /* if there are no read bits set, make write only */
324 if (!(mode
& S_IRUGO
))
325 return debugfs_create_file_unsafe(name
, mode
, parent
, value
,
328 return debugfs_create_file_unsafe(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_DEBUGFS_ATTRIBUTE(fops_u8
, debugfs_u8_get
, debugfs_u8_set
, "%llu\n");
342 DEFINE_DEBUGFS_ATTRIBUTE(fops_u8_ro
, debugfs_u8_get
, NULL
, "%llu\n");
343 DEFINE_DEBUGFS_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_unsafe(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_DEBUGFS_ATTRIBUTE(fops_u16
, debugfs_u16_get
, debugfs_u16_set
, "%llu\n");
388 DEFINE_DEBUGFS_ATTRIBUTE(fops_u16_ro
, debugfs_u16_get
, NULL
, "%llu\n");
389 DEFINE_DEBUGFS_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_unsafe(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_DEBUGFS_ATTRIBUTE(fops_u32
, debugfs_u32_get
, debugfs_u32_set
, "%llu\n");
434 DEFINE_DEBUGFS_ATTRIBUTE(fops_u32_ro
, debugfs_u32_get
, NULL
, "%llu\n");
435 DEFINE_DEBUGFS_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_unsafe(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_DEBUGFS_ATTRIBUTE(fops_u64
, debugfs_u64_get
, debugfs_u64_set
, "%llu\n");
481 DEFINE_DEBUGFS_ATTRIBUTE(fops_u64_ro
, debugfs_u64_get
, NULL
, "%llu\n");
482 DEFINE_DEBUGFS_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_unsafe(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_DEBUGFS_ATTRIBUTE(fops_ulong
, debugfs_ulong_get
, debugfs_ulong_set
,
529 DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_ro
, debugfs_ulong_get
, NULL
, "%llu\n");
530 DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_wo
, NULL
, debugfs_ulong_set
, "%llu\n");
533 * debugfs_create_ulong - create a debugfs file that is used to read and write
534 * an unsigned long value.
535 * @name: a pointer to a string containing the name of the file to create.
536 * @mode: the permission that the file should have
537 * @parent: a pointer to the parent dentry for this file. This should be a
538 * directory dentry if set. If this parameter is %NULL, then the
539 * file will be created in the root of the debugfs filesystem.
540 * @value: a pointer to the variable that the file should read to and write
543 * This function creates a file in debugfs with the given name that
544 * contains the value of the variable @value. If the @mode variable is so
545 * set, it can be read from, and written to.
547 * This function will return a pointer to a dentry if it succeeds. This
548 * pointer must be passed to the debugfs_remove() function when the file is
549 * to be removed (no automatic cleanup happens if your module is unloaded,
550 * you are responsible here.) If an error occurs, %NULL will be returned.
552 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
553 * returned. It is not wise to check for this value, but rather, check for
554 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
557 struct dentry
*debugfs_create_ulong(const char *name
, umode_t mode
,
558 struct dentry
*parent
, unsigned long *value
)
560 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
,
561 &fops_ulong
, &fops_ulong_ro
,
564 EXPORT_SYMBOL_GPL(debugfs_create_ulong
);
566 DEFINE_DEBUGFS_ATTRIBUTE(fops_x8
, debugfs_u8_get
, debugfs_u8_set
, "0x%02llx\n");
567 DEFINE_DEBUGFS_ATTRIBUTE(fops_x8_ro
, debugfs_u8_get
, NULL
, "0x%02llx\n");
568 DEFINE_DEBUGFS_ATTRIBUTE(fops_x8_wo
, NULL
, debugfs_u8_set
, "0x%02llx\n");
570 DEFINE_DEBUGFS_ATTRIBUTE(fops_x16
, debugfs_u16_get
, debugfs_u16_set
,
572 DEFINE_DEBUGFS_ATTRIBUTE(fops_x16_ro
, debugfs_u16_get
, NULL
, "0x%04llx\n");
573 DEFINE_DEBUGFS_ATTRIBUTE(fops_x16_wo
, NULL
, debugfs_u16_set
, "0x%04llx\n");
575 DEFINE_DEBUGFS_ATTRIBUTE(fops_x32
, debugfs_u32_get
, debugfs_u32_set
,
577 DEFINE_DEBUGFS_ATTRIBUTE(fops_x32_ro
, debugfs_u32_get
, NULL
, "0x%08llx\n");
578 DEFINE_DEBUGFS_ATTRIBUTE(fops_x32_wo
, NULL
, debugfs_u32_set
, "0x%08llx\n");
580 DEFINE_DEBUGFS_ATTRIBUTE(fops_x64
, debugfs_u64_get
, debugfs_u64_set
,
582 DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_ro
, debugfs_u64_get
, NULL
, "0x%016llx\n");
583 DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_wo
, NULL
, debugfs_u64_set
, "0x%016llx\n");
586 * 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
588 * These functions are exactly the same as the above functions (but use a hex
589 * output for the decimal challenged). For details look at the above unsigned
594 * debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value
595 * @name: a pointer to a string containing the name of the file to create.
596 * @mode: the permission that the file should have
597 * @parent: a pointer to the parent dentry for this file. This should be a
598 * directory dentry if set. If this parameter is %NULL, then the
599 * file will be created in the root of the debugfs filesystem.
600 * @value: a pointer to the variable that the file should read to and write
603 struct dentry
*debugfs_create_x8(const char *name
, umode_t mode
,
604 struct dentry
*parent
, u8
*value
)
606 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
, &fops_x8
,
607 &fops_x8_ro
, &fops_x8_wo
);
609 EXPORT_SYMBOL_GPL(debugfs_create_x8
);
612 * debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value
613 * @name: a pointer to a string containing the name of the file to create.
614 * @mode: the permission that the file should have
615 * @parent: a pointer to the parent dentry for this file. This should be a
616 * directory dentry if set. If this parameter is %NULL, then the
617 * file will be created in the root of the debugfs filesystem.
618 * @value: a pointer to the variable that the file should read to and write
621 struct dentry
*debugfs_create_x16(const char *name
, umode_t mode
,
622 struct dentry
*parent
, u16
*value
)
624 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
, &fops_x16
,
625 &fops_x16_ro
, &fops_x16_wo
);
627 EXPORT_SYMBOL_GPL(debugfs_create_x16
);
630 * debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value
631 * @name: a pointer to a string containing the name of the file to create.
632 * @mode: the permission that the file should have
633 * @parent: a pointer to the parent dentry for this file. This should be a
634 * directory dentry if set. If this parameter is %NULL, then the
635 * file will be created in the root of the debugfs filesystem.
636 * @value: a pointer to the variable that the file should read to and write
639 struct dentry
*debugfs_create_x32(const char *name
, umode_t mode
,
640 struct dentry
*parent
, u32
*value
)
642 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
, &fops_x32
,
643 &fops_x32_ro
, &fops_x32_wo
);
645 EXPORT_SYMBOL_GPL(debugfs_create_x32
);
648 * debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit value
649 * @name: a pointer to a string containing the name of the file to create.
650 * @mode: the permission that the file should have
651 * @parent: a pointer to the parent dentry for this file. This should be a
652 * directory dentry if set. If this parameter is %NULL, then the
653 * file will be created in the root of the debugfs filesystem.
654 * @value: a pointer to the variable that the file should read to and write
657 struct dentry
*debugfs_create_x64(const char *name
, umode_t mode
,
658 struct dentry
*parent
, u64
*value
)
660 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
, &fops_x64
,
661 &fops_x64_ro
, &fops_x64_wo
);
663 EXPORT_SYMBOL_GPL(debugfs_create_x64
);
666 static int debugfs_size_t_set(void *data
, u64 val
)
668 *(size_t *)data
= val
;
671 static int debugfs_size_t_get(void *data
, u64
*val
)
673 *val
= *(size_t *)data
;
676 DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t
, debugfs_size_t_get
, debugfs_size_t_set
,
677 "%llu\n"); /* %llu and %zu are more or less the same */
678 DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_ro
, debugfs_size_t_get
, NULL
, "%llu\n");
679 DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_wo
, NULL
, debugfs_size_t_set
, "%llu\n");
682 * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value
683 * @name: a pointer to a string containing the name of the file to create.
684 * @mode: the permission that the file should have
685 * @parent: a pointer to the parent dentry for this file. This should be a
686 * directory dentry if set. If this parameter is %NULL, then the
687 * file will be created in the root of the debugfs filesystem.
688 * @value: a pointer to the variable that the file should read to and write
691 struct dentry
*debugfs_create_size_t(const char *name
, umode_t mode
,
692 struct dentry
*parent
, size_t *value
)
694 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
,
695 &fops_size_t
, &fops_size_t_ro
,
698 EXPORT_SYMBOL_GPL(debugfs_create_size_t
);
700 static int debugfs_atomic_t_set(void *data
, u64 val
)
702 atomic_set((atomic_t
*)data
, val
);
705 static int debugfs_atomic_t_get(void *data
, u64
*val
)
707 *val
= atomic_read((atomic_t
*)data
);
710 DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t
, debugfs_atomic_t_get
,
711 debugfs_atomic_t_set
, "%lld\n");
712 DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t_ro
, debugfs_atomic_t_get
, NULL
,
714 DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t_wo
, NULL
, debugfs_atomic_t_set
,
718 * debugfs_create_atomic_t - create a debugfs file that is used to read and
719 * write an atomic_t value
720 * @name: a pointer to a string containing the name of the file to create.
721 * @mode: the permission that the file should have
722 * @parent: a pointer to the parent dentry for this file. This should be a
723 * directory dentry if set. If this parameter is %NULL, then the
724 * file will be created in the root of the debugfs filesystem.
725 * @value: a pointer to the variable that the file should read to and write
728 struct dentry
*debugfs_create_atomic_t(const char *name
, umode_t mode
,
729 struct dentry
*parent
, atomic_t
*value
)
731 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
,
732 &fops_atomic_t
, &fops_atomic_t_ro
,
735 EXPORT_SYMBOL_GPL(debugfs_create_atomic_t
);
737 ssize_t
debugfs_read_file_bool(struct file
*file
, char __user
*user_buf
,
738 size_t count
, loff_t
*ppos
)
744 r
= debugfs_use_file_start(F_DENTRY(file
), &srcu_idx
);
746 val
= *(bool *)file
->private_data
;
747 debugfs_use_file_finish(srcu_idx
);
757 return simple_read_from_buffer(user_buf
, count
, ppos
, buf
, 2);
759 EXPORT_SYMBOL_GPL(debugfs_read_file_bool
);
761 ssize_t
debugfs_write_file_bool(struct file
*file
, const char __user
*user_buf
,
762 size_t count
, loff_t
*ppos
)
768 bool *val
= file
->private_data
;
770 buf_size
= min(count
, (sizeof(buf
)-1));
771 if (copy_from_user(buf
, user_buf
, buf_size
))
774 buf
[buf_size
] = '\0';
775 if (strtobool(buf
, &bv
) == 0) {
776 r
= debugfs_use_file_start(F_DENTRY(file
), &srcu_idx
);
779 debugfs_use_file_finish(srcu_idx
);
786 EXPORT_SYMBOL_GPL(debugfs_write_file_bool
);
788 static const struct file_operations fops_bool
= {
789 .read
= debugfs_read_file_bool
,
790 .write
= debugfs_write_file_bool
,
792 .llseek
= default_llseek
,
795 static const struct file_operations fops_bool_ro
= {
796 .read
= debugfs_read_file_bool
,
798 .llseek
= default_llseek
,
801 static const struct file_operations fops_bool_wo
= {
802 .write
= debugfs_write_file_bool
,
804 .llseek
= default_llseek
,
808 * debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
809 * @name: a pointer to a string containing the name of the file to create.
810 * @mode: the permission that the file should have
811 * @parent: a pointer to the parent dentry for this file. This should be a
812 * directory dentry if set. If this parameter is %NULL, then the
813 * file will be created in the root of the debugfs filesystem.
814 * @value: a pointer to the variable that the file should read to and write
817 * This function creates a file in debugfs with the given name that
818 * contains the value of the variable @value. If the @mode variable is so
819 * set, it can be read from, and written to.
821 * This function will return a pointer to a dentry if it succeeds. This
822 * pointer must be passed to the debugfs_remove() function when the file is
823 * to be removed (no automatic cleanup happens if your module is unloaded,
824 * you are responsible here.) If an error occurs, %NULL will be returned.
826 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
827 * returned. It is not wise to check for this value, but rather, check for
828 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
831 struct dentry
*debugfs_create_bool(const char *name
, umode_t mode
,
832 struct dentry
*parent
, bool *value
)
834 return debugfs_create_mode_unsafe(name
, mode
, parent
, value
, &fops_bool
,
835 &fops_bool_ro
, &fops_bool_wo
);
837 EXPORT_SYMBOL_GPL(debugfs_create_bool
);
839 static ssize_t
read_file_blob(struct file
*file
, char __user
*user_buf
,
840 size_t count
, loff_t
*ppos
)
842 struct debugfs_blob_wrapper
*blob
= file
->private_data
;
846 r
= debugfs_use_file_start(F_DENTRY(file
), &srcu_idx
);
848 r
= simple_read_from_buffer(user_buf
, count
, ppos
, blob
->data
,
850 debugfs_use_file_finish(srcu_idx
);
854 static const struct file_operations fops_blob
= {
855 .read
= read_file_blob
,
857 .llseek
= default_llseek
,
861 * debugfs_create_blob - create a debugfs file that is used to read a binary blob
862 * @name: a pointer to a string containing the name of the file to create.
863 * @mode: the permission that the file should have
864 * @parent: a pointer to the parent dentry for this file. This should be a
865 * directory dentry if set. If this parameter is %NULL, then the
866 * file will be created in the root of the debugfs filesystem.
867 * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer
868 * to the blob data and the size of the data.
870 * This function creates a file in debugfs with the given name that exports
871 * @blob->data as a binary blob. If the @mode variable is so set it can be
872 * read from. Writing is not supported.
874 * This function will return a pointer to a dentry if it succeeds. This
875 * pointer must be passed to the debugfs_remove() function when the file is
876 * to be removed (no automatic cleanup happens if your module is unloaded,
877 * you are responsible here.) If an error occurs, %NULL will be returned.
879 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
880 * returned. It is not wise to check for this value, but rather, check for
881 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
884 struct dentry
*debugfs_create_blob(const char *name
, umode_t mode
,
885 struct dentry
*parent
,
886 struct debugfs_blob_wrapper
*blob
)
888 return debugfs_create_file_unsafe(name
, mode
, parent
, blob
, &fops_blob
);
890 EXPORT_SYMBOL_GPL(debugfs_create_blob
);
897 static size_t u32_format_array(char *buf
, size_t bufsize
,
898 u32
*array
, int array_size
)
902 while (--array_size
>= 0) {
904 char term
= array_size
? ' ' : '\n';
906 len
= snprintf(buf
, bufsize
, "%u%c", *array
++, term
);
915 static int u32_array_open(struct inode
*inode
, struct file
*file
)
917 struct array_data
*data
= inode
->i_private
;
918 int size
, elements
= data
->elements
;
923 * - 10 digits + ' '/'\n' = 11 bytes per number
924 * - terminating NUL character
927 buf
= kmalloc(size
+1, GFP_KERNEL
);
932 file
->private_data
= buf
;
933 u32_format_array(buf
, size
, data
->array
, data
->elements
);
935 return nonseekable_open(inode
, file
);
938 static ssize_t
u32_array_read(struct file
*file
, char __user
*buf
, size_t len
,
941 size_t size
= strlen(file
->private_data
);
943 return simple_read_from_buffer(buf
, len
, ppos
,
944 file
->private_data
, size
);
947 static int u32_array_release(struct inode
*inode
, struct file
*file
)
949 kfree(file
->private_data
);
954 static const struct file_operations u32_array_fops
= {
955 .owner
= THIS_MODULE
,
956 .open
= u32_array_open
,
957 .release
= u32_array_release
,
958 .read
= u32_array_read
,
963 * debugfs_create_u32_array - create a debugfs file that is used to read u32
965 * @name: a pointer to a string containing the name of the file to create.
966 * @mode: the permission that the file should have.
967 * @parent: a pointer to the parent dentry for this file. This should be a
968 * directory dentry if set. If this parameter is %NULL, then the
969 * file will be created in the root of the debugfs filesystem.
970 * @array: u32 array that provides data.
971 * @elements: total number of elements in the array.
973 * This function creates a file in debugfs with the given name that exports
974 * @array as data. If the @mode variable is so set it can be read from.
975 * Writing is not supported. Seek within the file is also not supported.
976 * Once array is created its size can not be changed.
978 * The function returns a pointer to dentry on success. If debugfs is not
979 * enabled in the kernel, the value -%ENODEV will be returned.
981 struct dentry
*debugfs_create_u32_array(const char *name
, umode_t mode
,
982 struct dentry
*parent
,
983 u32
*array
, u32 elements
)
985 struct array_data
*data
= kmalloc(sizeof(*data
), GFP_KERNEL
);
991 data
->elements
= elements
;
993 return debugfs_create_file_unsafe(name
, mode
, parent
, data
,
996 EXPORT_SYMBOL_GPL(debugfs_create_u32_array
);
998 #ifdef CONFIG_HAS_IOMEM
1001 * The regset32 stuff is used to print 32-bit registers using the
1002 * seq_file utilities. We offer printing a register set in an already-opened
1003 * sequential file or create a debugfs file that only prints a regset32.
1007 * debugfs_print_regs32 - use seq_print to describe a set of registers
1008 * @s: the seq_file structure being used to generate output
1009 * @regs: an array if struct debugfs_reg32 structures
1010 * @nregs: the length of the above array
1011 * @base: the base address to be used in reading the registers
1012 * @prefix: a string to be prefixed to every output line
1014 * This function outputs a text block describing the current values of
1015 * some 32-bit hardware registers. It is meant to be used within debugfs
1016 * files based on seq_file that need to show registers, intermixed with other
1017 * information. The prefix argument may be used to specify a leading string,
1018 * because some peripherals have several blocks of identical registers,
1019 * for example configuration of dma channels
1021 void debugfs_print_regs32(struct seq_file
*s
, const struct debugfs_reg32
*regs
,
1022 int nregs
, void __iomem
*base
, char *prefix
)
1026 for (i
= 0; i
< nregs
; i
++, regs
++) {
1028 seq_printf(s
, "%s", prefix
);
1029 seq_printf(s
, "%s = 0x%08x\n", regs
->name
,
1030 readl(base
+ regs
->offset
));
1031 if (seq_has_overflowed(s
))
1035 EXPORT_SYMBOL_GPL(debugfs_print_regs32
);
1037 static int debugfs_show_regset32(struct seq_file
*s
, void *data
)
1039 struct debugfs_regset32
*regset
= s
->private;
1041 debugfs_print_regs32(s
, regset
->regs
, regset
->nregs
, regset
->base
, "");
1045 static int debugfs_open_regset32(struct inode
*inode
, struct file
*file
)
1047 return single_open(file
, debugfs_show_regset32
, inode
->i_private
);
1050 static const struct file_operations fops_regset32
= {
1051 .open
= debugfs_open_regset32
,
1053 .llseek
= seq_lseek
,
1054 .release
= single_release
,
1058 * debugfs_create_regset32 - create a debugfs file that returns register values
1059 * @name: a pointer to a string containing the name of the file to create.
1060 * @mode: the permission that the file should have
1061 * @parent: a pointer to the parent dentry for this file. This should be a
1062 * directory dentry if set. If this parameter is %NULL, then the
1063 * file will be created in the root of the debugfs filesystem.
1064 * @regset: a pointer to a struct debugfs_regset32, which contains a pointer
1065 * to an array of register definitions, the array size and the base
1066 * address where the register bank is to be found.
1068 * This function creates a file in debugfs with the given name that reports
1069 * the names and values of a set of 32-bit registers. If the @mode variable
1070 * is so set it can be read from. Writing is not supported.
1072 * This function will return a pointer to a dentry if it succeeds. This
1073 * pointer must be passed to the debugfs_remove() function when the file is
1074 * to be removed (no automatic cleanup happens if your module is unloaded,
1075 * you are responsible here.) If an error occurs, %NULL will be returned.
1077 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
1078 * returned. It is not wise to check for this value, but rather, check for
1079 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
1082 struct dentry
*debugfs_create_regset32(const char *name
, umode_t mode
,
1083 struct dentry
*parent
,
1084 struct debugfs_regset32
*regset
)
1086 return debugfs_create_file(name
, mode
, parent
, regset
, &fops_regset32
);
1088 EXPORT_SYMBOL_GPL(debugfs_create_regset32
);
1090 #endif /* CONFIG_HAS_IOMEM */
1092 struct debugfs_devm_entry
{
1093 int (*read
)(struct seq_file
*seq
, void *data
);
1097 static int debugfs_devm_entry_open(struct inode
*inode
, struct file
*f
)
1099 struct debugfs_devm_entry
*entry
= inode
->i_private
;
1101 return single_open(f
, entry
->read
, entry
->dev
);
1104 static const struct file_operations debugfs_devm_entry_ops
= {
1105 .owner
= THIS_MODULE
,
1106 .open
= debugfs_devm_entry_open
,
1107 .release
= single_release
,
1113 * debugfs_create_devm_seqfile - create a debugfs file that is bound to device.
1115 * @dev: device related to this debugfs file.
1116 * @name: name of the debugfs file.
1117 * @parent: a pointer to the parent dentry for this file. This should be a
1118 * directory dentry if set. If this parameter is %NULL, then the
1119 * file will be created in the root of the debugfs filesystem.
1120 * @read_fn: function pointer called to print the seq_file content.
1122 struct dentry
*debugfs_create_devm_seqfile(struct device
*dev
, const char *name
,
1123 struct dentry
*parent
,
1124 int (*read_fn
)(struct seq_file
*s
,
1127 struct debugfs_devm_entry
*entry
;
1130 return ERR_PTR(-ENOENT
);
1132 entry
= devm_kzalloc(dev
, sizeof(*entry
), GFP_KERNEL
);
1134 return ERR_PTR(-ENOMEM
);
1136 entry
->read
= read_fn
;
1139 return debugfs_create_file(name
, S_IRUGO
, parent
, entry
,
1140 &debugfs_devm_entry_ops
);
1142 EXPORT_SYMBOL_GPL(debugfs_create_devm_seqfile
);