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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Tejun Heo6d66f5c2007-09-20 17:31:38 +09002 * fs/sysfs/file.c - sysfs regular (text) file implementation
3 *
4 * Copyright (c) 2001-3 Patrick Mochel
5 * Copyright (c) 2007 SUSE Linux Products GmbH
6 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
7 *
8 * This file is released under the GPLv2.
9 *
10 * Please see Documentation/filesystems/sysfs.txt for more information.
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 */
12
13#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/kobject.h>
Andrew Morton815d2d52008-03-04 15:09:07 -080015#include <linux/kallsyms.h>
Robert P. J. Dayc6f87732008-03-13 22:41:52 -040016#include <linux/slab.h>
Oliver Neukum94bebf42006-12-20 10:52:44 +010017#include <linux/list.h>
Dave Young52e8c202007-07-26 11:03:54 +000018#include <linux/mutex.h>
Tejun Heo13c589d2013-10-01 17:42:02 -040019#include <linux/seq_file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
21#include "sysfs.h"
Tejun Heo414985a2013-11-28 14:54:34 -050022#include "../kernfs/kernfs-internal.h"
Tejun Heof6acf8b2013-11-28 14:54:21 -050023
24/*
Tejun Heo324a56e2013-12-11 14:11:53 -050025 * Determine ktype->sysfs_ops for the given kernfs_node. This function
Tejun Heo375b6112013-10-01 17:41:57 -040026 * must be called while holding an active reference.
27 */
Tejun Heo324a56e2013-12-11 14:11:53 -050028static const struct sysfs_ops *sysfs_file_ops(struct kernfs_node *kn)
Tejun Heo375b6112013-10-01 17:41:57 -040029{
Tejun Heoadc5e8b2013-12-11 14:11:54 -050030 struct kobject *kobj = kn->parent->priv;
Tejun Heo375b6112013-10-01 17:41:57 -040031
Tejun Heodf23fc32013-12-11 14:11:56 -050032 if (kn->flags & KERNFS_LOCKDEP)
Tejun Heo324a56e2013-12-11 14:11:53 -050033 lockdep_assert_held(kn);
Tejun Heo375b6112013-10-01 17:41:57 -040034 return kobj->ktype ? kobj->ktype->sysfs_ops : NULL;
35}
36
Tejun Heo13c589d2013-10-01 17:42:02 -040037/*
38 * Reads on sysfs are handled through seq_file, which takes care of hairy
39 * details like buffering and seeking. The following function pipes
40 * sysfs_ops->show() result through seq_file.
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 */
Tejun Heoc2b19da2013-11-28 14:54:16 -050042static int sysfs_kf_seq_show(struct seq_file *sf, void *v)
Linus Torvalds1da177e2005-04-16 15:20:36 -070043{
Tejun Heoc525aad2013-12-11 14:11:55 -050044 struct kernfs_open_file *of = sf->private;
Tejun Heoadc5e8b2013-12-11 14:11:54 -050045 struct kobject *kobj = of->kn->parent->priv;
Tejun Heo324a56e2013-12-11 14:11:53 -050046 const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047 ssize_t count;
Tejun Heoc2b19da2013-11-28 14:54:16 -050048 char *buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
Tejun Heof5c16f22014-05-19 15:52:10 -040050 /* acquire buffer and ensure that it's >= PAGE_SIZE and clear */
Tejun Heo13c589d2013-10-01 17:42:02 -040051 count = seq_get_buf(sf, &buf);
52 if (count < PAGE_SIZE) {
53 seq_commit(sf, -1);
54 return 0;
55 }
Tejun Heof5c16f22014-05-19 15:52:10 -040056 memset(buf, 0, PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Tejun Heo13c589d2013-10-01 17:42:02 -040058 /*
Tejun Heoc2b19da2013-11-28 14:54:16 -050059 * Invoke show(). Control may reach here via seq file lseek even
60 * if @ops->show() isn't implemented.
Tejun Heo13c589d2013-10-01 17:42:02 -040061 */
Tejun Heoc2b19da2013-11-28 14:54:16 -050062 if (ops->show) {
Tejun Heo324a56e2013-12-11 14:11:53 -050063 count = ops->show(kobj, of->kn->priv, buf);
Tejun Heoc2b19da2013-11-28 14:54:16 -050064 if (count < 0)
65 return count;
66 }
Tejun Heo0ab66082007-06-14 03:45:16 +090067
Miao Xie8118a852007-11-21 14:55:19 -080068 /*
69 * The code works fine with PAGE_SIZE return but it's likely to
70 * indicate truncated result or overflow in normal use cases.
71 */
Andrew Morton815d2d52008-03-04 15:09:07 -080072 if (count >= (ssize_t)PAGE_SIZE) {
73 print_symbol("fill_read_buffer: %s returned bad count\n",
74 (unsigned long)ops->show);
75 /* Try to struggle along */
76 count = PAGE_SIZE - 1;
77 }
Tejun Heo13c589d2013-10-01 17:42:02 -040078 seq_commit(sf, count);
79 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070080}
81
Tejun Heoc525aad2013-12-11 14:11:55 -050082static ssize_t sysfs_kf_bin_read(struct kernfs_open_file *of, char *buf,
Tejun Heoc2b19da2013-11-28 14:54:16 -050083 size_t count, loff_t pos)
Tejun Heo2f0c6b72013-10-01 17:42:06 -040084{
Tejun Heo324a56e2013-12-11 14:11:53 -050085 struct bin_attribute *battr = of->kn->priv;
Tejun Heoadc5e8b2013-12-11 14:11:54 -050086 struct kobject *kobj = of->kn->parent->priv;
Tejun Heoc2b19da2013-11-28 14:54:16 -050087 loff_t size = file_inode(of->file)->i_size;
Tejun Heo2f0c6b72013-10-01 17:42:06 -040088
Tejun Heoc2b19da2013-11-28 14:54:16 -050089 if (!count)
Tejun Heo2f0c6b72013-10-01 17:42:06 -040090 return 0;
91
92 if (size) {
Vladimir Zapolskiyeaa5cd92015-05-22 00:21:16 +030093 if (pos >= size)
Tejun Heo2f0c6b72013-10-01 17:42:06 -040094 return 0;
Tejun Heoc2b19da2013-11-28 14:54:16 -050095 if (pos + count > size)
96 count = size - pos;
Tejun Heo2f0c6b72013-10-01 17:42:06 -040097 }
98
Tejun Heoc2b19da2013-11-28 14:54:16 -050099 if (!battr->read)
100 return -EIO;
101
102 return battr->read(of->file, kobj, battr, buf, pos, count);
103}
104
NeilBrown4ef67a82014-10-14 16:57:26 +1100105/* kernfs read callback for regular sysfs files with pre-alloc */
106static ssize_t sysfs_kf_read(struct kernfs_open_file *of, char *buf,
107 size_t count, loff_t pos)
108{
109 const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
110 struct kobject *kobj = of->kn->parent->priv;
NeilBrownc8a139d2017-04-03 11:30:34 +1000111 ssize_t len;
NeilBrown4ef67a82014-10-14 16:57:26 +1100112
113 /*
114 * If buf != of->prealloc_buf, we don't know how
115 * large it is, so cannot safely pass it to ->show
116 */
Konstantin Khlebnikov17d07742016-06-22 21:42:16 +0300117 if (WARN_ON_ONCE(buf != of->prealloc_buf))
NeilBrown4ef67a82014-10-14 16:57:26 +1100118 return 0;
NeilBrown65da3482015-08-06 08:27:55 +1000119 len = ops->show(kobj, of->kn->priv, buf);
NeilBrownc8a139d2017-04-03 11:30:34 +1000120 if (len < 0)
121 return len;
Konstantin Khlebnikov17d07742016-06-22 21:42:16 +0300122 if (pos) {
123 if (len <= pos)
124 return 0;
125 len -= pos;
126 memmove(buf, buf + pos, len);
127 }
NeilBrownc8a139d2017-04-03 11:30:34 +1000128 return min_t(ssize_t, count, len);
NeilBrown4ef67a82014-10-14 16:57:26 +1100129}
130
Tejun Heo50b38ca2013-11-28 14:54:17 -0500131/* kernfs write callback for regular sysfs files */
Tejun Heoc525aad2013-12-11 14:11:55 -0500132static ssize_t sysfs_kf_write(struct kernfs_open_file *of, char *buf,
Tejun Heo50b38ca2013-11-28 14:54:17 -0500133 size_t count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134{
Tejun Heo324a56e2013-12-11 14:11:53 -0500135 const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
Tejun Heoadc5e8b2013-12-11 14:11:54 -0500136 struct kobject *kobj = of->kn->parent->priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137
Tejun Heo50b38ca2013-11-28 14:54:17 -0500138 if (!count)
139 return 0;
140
Tejun Heo324a56e2013-12-11 14:11:53 -0500141 return ops->store(kobj, of->kn->priv, buf, count);
Tejun Heo50b38ca2013-11-28 14:54:17 -0500142}
143
144/* kernfs write callback for bin sysfs files */
Tejun Heoc525aad2013-12-11 14:11:55 -0500145static ssize_t sysfs_kf_bin_write(struct kernfs_open_file *of, char *buf,
Tejun Heo50b38ca2013-11-28 14:54:17 -0500146 size_t count, loff_t pos)
147{
Tejun Heo324a56e2013-12-11 14:11:53 -0500148 struct bin_attribute *battr = of->kn->priv;
Tejun Heoadc5e8b2013-12-11 14:11:54 -0500149 struct kobject *kobj = of->kn->parent->priv;
Tejun Heo50b38ca2013-11-28 14:54:17 -0500150 loff_t size = file_inode(of->file)->i_size;
151
152 if (size) {
153 if (size <= pos)
Vladimir Zapolskiy09368962014-09-24 18:21:04 +0300154 return -EFBIG;
Tejun Heo50b38ca2013-11-28 14:54:17 -0500155 count = min_t(ssize_t, count, size - pos);
Tejun Heo8ef445f2013-10-01 17:42:01 -0400156 }
Tejun Heo50b38ca2013-11-28 14:54:17 -0500157 if (!count)
158 return 0;
Tejun Heo0ab66082007-06-14 03:45:16 +0900159
Tejun Heo50b38ca2013-11-28 14:54:17 -0500160 if (!battr->write)
161 return -EIO;
Tejun Heof9b9a622013-10-01 17:42:05 -0400162
Tejun Heo50b38ca2013-11-28 14:54:17 -0500163 return battr->write(of->file, kobj, battr, buf, pos, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164}
165
Tejun Heoc525aad2013-12-11 14:11:55 -0500166static int sysfs_kf_bin_mmap(struct kernfs_open_file *of,
Tejun Heofdbffaa2013-11-28 14:54:18 -0500167 struct vm_area_struct *vma)
168{
Tejun Heo324a56e2013-12-11 14:11:53 -0500169 struct bin_attribute *battr = of->kn->priv;
Tejun Heoadc5e8b2013-12-11 14:11:54 -0500170 struct kobject *kobj = of->kn->parent->priv;
Tejun Heofdbffaa2013-11-28 14:54:18 -0500171
Tejun Heofdbffaa2013-11-28 14:54:18 -0500172 return battr->mmap(of->file, kobj, battr, vma);
173}
174
Tejun Heo324a56e2013-12-11 14:11:53 -0500175void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr)
NeilBrown4508a7a2006-03-20 17:53:53 +1100176{
Tejun Heo324a56e2013-12-11 14:11:53 -0500177 struct kernfs_node *kn = kobj->sd, *tmp;
NeilBrown4508a7a2006-03-20 17:53:53 +1100178
Tejun Heo324a56e2013-12-11 14:11:53 -0500179 if (kn && dir)
180 kn = kernfs_find_and_get(kn, dir);
Tejun Heo024f6472013-11-28 14:54:27 -0500181 else
Tejun Heo324a56e2013-12-11 14:11:53 -0500182 kernfs_get(kn);
Tejun Heo51225032007-06-14 04:27:25 +0900183
Tejun Heo324a56e2013-12-11 14:11:53 -0500184 if (kn && attr) {
185 tmp = kernfs_find_and_get(kn, attr);
186 kernfs_put(kn);
187 kn = tmp;
Tejun Heo024f6472013-11-28 14:54:27 -0500188 }
189
Tejun Heo324a56e2013-12-11 14:11:53 -0500190 if (kn) {
191 kernfs_notify(kn);
192 kernfs_put(kn);
Tejun Heo024f6472013-11-28 14:54:27 -0500193 }
NeilBrown4508a7a2006-03-20 17:53:53 +1100194}
195EXPORT_SYMBOL_GPL(sysfs_notify);
196
Tejun Heof6acf8b2013-11-28 14:54:21 -0500197static const struct kernfs_ops sysfs_file_kfops_empty = {
198};
199
200static const struct kernfs_ops sysfs_file_kfops_ro = {
201 .seq_show = sysfs_kf_seq_show,
202};
203
204static const struct kernfs_ops sysfs_file_kfops_wo = {
205 .write = sysfs_kf_write,
206};
207
208static const struct kernfs_ops sysfs_file_kfops_rw = {
209 .seq_show = sysfs_kf_seq_show,
210 .write = sysfs_kf_write,
211};
212
NeilBrown4ef67a82014-10-14 16:57:26 +1100213static const struct kernfs_ops sysfs_prealloc_kfops_ro = {
214 .read = sysfs_kf_read,
215 .prealloc = true,
216};
217
NeilBrown2b758692014-10-13 16:41:28 +1100218static const struct kernfs_ops sysfs_prealloc_kfops_wo = {
219 .write = sysfs_kf_write,
220 .prealloc = true,
221};
222
223static const struct kernfs_ops sysfs_prealloc_kfops_rw = {
NeilBrown4ef67a82014-10-14 16:57:26 +1100224 .read = sysfs_kf_read,
NeilBrown2b758692014-10-13 16:41:28 +1100225 .write = sysfs_kf_write,
226 .prealloc = true,
227};
228
Tejun Heof6acf8b2013-11-28 14:54:21 -0500229static const struct kernfs_ops sysfs_bin_kfops_ro = {
230 .read = sysfs_kf_bin_read,
231};
232
233static const struct kernfs_ops sysfs_bin_kfops_wo = {
234 .write = sysfs_kf_bin_write,
235};
236
237static const struct kernfs_ops sysfs_bin_kfops_rw = {
238 .read = sysfs_kf_bin_read,
239 .write = sysfs_kf_bin_write,
Tejun Heo9b2db6e2013-12-10 09:29:17 -0500240};
241
242static const struct kernfs_ops sysfs_bin_kfops_mmap = {
243 .read = sysfs_kf_bin_read,
244 .write = sysfs_kf_bin_write,
Tejun Heof6acf8b2013-11-28 14:54:21 -0500245 .mmap = sysfs_kf_bin_mmap,
246};
247
Tejun Heo324a56e2013-12-11 14:11:53 -0500248int sysfs_add_file_mode_ns(struct kernfs_node *parent,
Tejun Heoa7dc66d2013-11-28 14:54:23 -0500249 const struct attribute *attr, bool is_bin,
Tejun Heo496f7392013-11-28 14:54:24 -0500250 umode_t mode, const void *ns)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251{
Tejun Heo517e64f2013-11-28 14:54:29 -0500252 struct lock_class_key *key = NULL;
Tejun Heof6acf8b2013-11-28 14:54:21 -0500253 const struct kernfs_ops *ops;
Tejun Heo324a56e2013-12-11 14:11:53 -0500254 struct kernfs_node *kn;
Tejun Heo471bd7b2013-11-28 14:54:22 -0500255 loff_t size;
Tejun Heoa26cd722007-06-14 03:45:14 +0900256
Tejun Heoa7dc66d2013-11-28 14:54:23 -0500257 if (!is_bin) {
Tejun Heo324a56e2013-12-11 14:11:53 -0500258 struct kobject *kobj = parent->priv;
Tejun Heof6acf8b2013-11-28 14:54:21 -0500259 const struct sysfs_ops *sysfs_ops = kobj->ktype->sysfs_ops;
260
261 /* every kobject with an attribute needs a ktype assigned */
262 if (WARN(!sysfs_ops, KERN_ERR
263 "missing sysfs attribute operations for kobject: %s\n",
264 kobject_name(kobj)))
265 return -EINVAL;
266
NeilBrown2b758692014-10-13 16:41:28 +1100267 if (sysfs_ops->show && sysfs_ops->store) {
268 if (mode & SYSFS_PREALLOC)
269 ops = &sysfs_prealloc_kfops_rw;
270 else
271 ops = &sysfs_file_kfops_rw;
NeilBrown4ef67a82014-10-14 16:57:26 +1100272 } else if (sysfs_ops->show) {
273 if (mode & SYSFS_PREALLOC)
274 ops = &sysfs_prealloc_kfops_ro;
275 else
276 ops = &sysfs_file_kfops_ro;
277 } else if (sysfs_ops->store) {
NeilBrown2b758692014-10-13 16:41:28 +1100278 if (mode & SYSFS_PREALLOC)
279 ops = &sysfs_prealloc_kfops_wo;
280 else
281 ops = &sysfs_file_kfops_wo;
282 } else
Tejun Heof6acf8b2013-11-28 14:54:21 -0500283 ops = &sysfs_file_kfops_empty;
Tejun Heo471bd7b2013-11-28 14:54:22 -0500284
285 size = PAGE_SIZE;
Tejun Heof6acf8b2013-11-28 14:54:21 -0500286 } else {
287 struct bin_attribute *battr = (void *)attr;
288
Tejun Heo9b2db6e2013-12-10 09:29:17 -0500289 if (battr->mmap)
290 ops = &sysfs_bin_kfops_mmap;
291 else if (battr->read && battr->write)
Tejun Heof6acf8b2013-11-28 14:54:21 -0500292 ops = &sysfs_bin_kfops_rw;
293 else if (battr->read)
294 ops = &sysfs_bin_kfops_ro;
295 else if (battr->write)
296 ops = &sysfs_bin_kfops_wo;
297 else
298 ops = &sysfs_file_kfops_empty;
Tejun Heo471bd7b2013-11-28 14:54:22 -0500299
300 size = battr->size;
Tejun Heof6acf8b2013-11-28 14:54:21 -0500301 }
302
Tejun Heo517e64f2013-11-28 14:54:29 -0500303#ifdef CONFIG_DEBUG_LOCK_ALLOC
304 if (!attr->ignore_lockdep)
305 key = attr->key ?: (struct lock_class_key *)&attr->skey;
306#endif
NeilBrown2b758692014-10-13 16:41:28 +1100307 kn = __kernfs_create_file(parent, attr->name, mode & 0777, size, ops,
Tejun Heodfeb07502015-02-13 14:36:31 -0800308 (void *)attr, ns, key);
Tejun Heo324a56e2013-12-11 14:11:53 -0500309 if (IS_ERR(kn)) {
310 if (PTR_ERR(kn) == -EEXIST)
311 sysfs_warn_dup(parent, attr->name);
312 return PTR_ERR(kn);
Tejun Heo496f7392013-11-28 14:54:24 -0500313 }
314 return 0;
315}
316
Tejun Heo324a56e2013-12-11 14:11:53 -0500317int sysfs_add_file(struct kernfs_node *parent, const struct attribute *attr,
Tejun Heoa7dc66d2013-11-28 14:54:23 -0500318 bool is_bin)
James Bottomley0f423892008-03-20 20:47:52 -0500319{
Tejun Heo324a56e2013-12-11 14:11:53 -0500320 return sysfs_add_file_mode_ns(parent, attr, is_bin, attr->mode, NULL);
James Bottomley0f423892008-03-20 20:47:52 -0500321}
322
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323/**
Tejun Heo58292cbe2013-09-11 22:29:04 -0400324 * sysfs_create_file_ns - create an attribute file for an object with custom ns
325 * @kobj: object we're creating for
326 * @attr: attribute descriptor
327 * @ns: namespace the new file should belong to
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 */
Tejun Heo58292cbe2013-09-11 22:29:04 -0400329int sysfs_create_file_ns(struct kobject *kobj, const struct attribute *attr,
330 const void *ns)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331{
Tejun Heo608e2662007-06-14 04:27:22 +0900332 BUG_ON(!kobj || !kobj->sd || !attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333
Tejun Heoa7dc66d2013-11-28 14:54:23 -0500334 return sysfs_add_file_mode_ns(kobj->sd, attr, false, attr->mode, ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335
336}
Tejun Heo58292cbe2013-09-11 22:29:04 -0400337EXPORT_SYMBOL_GPL(sysfs_create_file_ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338
Andi Kleen1c205ae2010-01-05 12:48:01 +0100339int sysfs_create_files(struct kobject *kobj, const struct attribute **ptr)
340{
341 int err = 0;
342 int i;
343
344 for (i = 0; ptr[i] && !err; i++)
345 err = sysfs_create_file(kobj, ptr[i]);
346 if (err)
347 while (--i >= 0)
348 sysfs_remove_file(kobj, ptr[i]);
349 return err;
350}
Greg Kroah-Hartman1b866752013-08-21 16:17:47 -0700351EXPORT_SYMBOL_GPL(sysfs_create_files);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352
353/**
Alan Sterndfa87c82007-02-20 15:02:44 -0500354 * sysfs_add_file_to_group - add an attribute file to a pre-existing group.
355 * @kobj: object we're acting for.
356 * @attr: attribute descriptor.
357 * @group: group name.
358 */
359int sysfs_add_file_to_group(struct kobject *kobj,
360 const struct attribute *attr, const char *group)
361{
Tejun Heo324a56e2013-12-11 14:11:53 -0500362 struct kernfs_node *parent;
Alan Sterndfa87c82007-02-20 15:02:44 -0500363 int error;
364
Tejun Heoccf73cf2013-11-28 14:54:30 -0500365 if (group) {
Tejun Heo324a56e2013-12-11 14:11:53 -0500366 parent = kernfs_find_and_get(kobj->sd, group);
Tejun Heoccf73cf2013-11-28 14:54:30 -0500367 } else {
Tejun Heo324a56e2013-12-11 14:11:53 -0500368 parent = kobj->sd;
369 kernfs_get(parent);
Tejun Heoccf73cf2013-11-28 14:54:30 -0500370 }
James Bottomley11f24fb2008-01-02 18:44:05 -0600371
Tejun Heo324a56e2013-12-11 14:11:53 -0500372 if (!parent)
Tejun Heo608e2662007-06-14 04:27:22 +0900373 return -ENOENT;
374
Tejun Heo324a56e2013-12-11 14:11:53 -0500375 error = sysfs_add_file(parent, attr, false);
376 kernfs_put(parent);
Tejun Heo608e2662007-06-14 04:27:22 +0900377
Alan Sterndfa87c82007-02-20 15:02:44 -0500378 return error;
379}
380EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
381
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382/**
Kay Sievers31e5abe2005-04-18 21:57:32 -0700383 * sysfs_chmod_file - update the modified mode value on an object attribute.
384 * @kobj: object we're acting for.
385 * @attr: attribute descriptor.
386 * @mode: file permissions.
387 *
388 */
Jean Delvare49c19402010-07-02 16:54:05 +0200389int sysfs_chmod_file(struct kobject *kobj, const struct attribute *attr,
Al Viro48176a92011-07-24 03:40:40 -0400390 umode_t mode)
Kay Sievers31e5abe2005-04-18 21:57:32 -0700391{
Tejun Heo324a56e2013-12-11 14:11:53 -0500392 struct kernfs_node *kn;
Maneesh Sonibc062b12005-07-29 12:13:35 -0700393 struct iattr newattrs;
Tejun Heo51225032007-06-14 04:27:25 +0900394 int rc;
Kay Sievers31e5abe2005-04-18 21:57:32 -0700395
Tejun Heo324a56e2013-12-11 14:11:53 -0500396 kn = kernfs_find_and_get(kobj->sd, attr->name);
397 if (!kn)
Tejun Heo5d604182013-11-23 17:21:52 -0500398 return -ENOENT;
Tejun Heo51225032007-06-14 04:27:25 +0900399
Tejun Heoadc5e8b2013-12-11 14:11:54 -0500400 newattrs.ia_mode = (mode & S_IALLUGO) | (kn->mode & ~S_IALLUGO);
Eric W. Biederman4c6974f2009-11-07 23:27:02 -0800401 newattrs.ia_valid = ATTR_MODE;
Tejun Heof88123e2007-09-20 16:05:10 +0900402
Tejun Heo324a56e2013-12-11 14:11:53 -0500403 rc = kernfs_setattr(kn, &newattrs);
Tejun Heo5d604182013-11-23 17:21:52 -0500404
Tejun Heo324a56e2013-12-11 14:11:53 -0500405 kernfs_put(kn);
Tejun Heo51225032007-06-14 04:27:25 +0900406 return rc;
Kay Sievers31e5abe2005-04-18 21:57:32 -0700407}
408EXPORT_SYMBOL_GPL(sysfs_chmod_file);
409
Kay Sievers31e5abe2005-04-18 21:57:32 -0700410/**
Tejun Heo58292cbe2013-09-11 22:29:04 -0400411 * sysfs_remove_file_ns - remove an object attribute with a custom ns tag
412 * @kobj: object we're acting for
413 * @attr: attribute descriptor
414 * @ns: namespace tag of the file to remove
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 *
Tejun Heo58292cbe2013-09-11 22:29:04 -0400416 * Hash the attribute name and namespace tag and kill the victim.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417 */
Tejun Heo58292cbe2013-09-11 22:29:04 -0400418void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
419 const void *ns)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420{
Tejun Heo324a56e2013-12-11 14:11:53 -0500421 struct kernfs_node *parent = kobj->sd;
Eric W. Biederman487505c2011-10-12 21:53:38 +0000422
Tejun Heo324a56e2013-12-11 14:11:53 -0500423 kernfs_remove_by_name_ns(parent, attr->name, ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424}
Tejun Heo58292cbe2013-09-11 22:29:04 -0400425EXPORT_SYMBOL_GPL(sysfs_remove_file_ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426
Tejun Heo6b0afc22014-02-03 14:03:01 -0500427/**
428 * sysfs_remove_file_self - remove an object attribute from its own method
429 * @kobj: object we're acting for
430 * @attr: attribute descriptor
431 *
432 * See kernfs_remove_self() for details.
433 */
434bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr)
435{
436 struct kernfs_node *parent = kobj->sd;
437 struct kernfs_node *kn;
438 bool ret;
439
440 kn = kernfs_find_and_get(parent, attr->name);
441 if (WARN_ON_ONCE(!kn))
442 return false;
443
444 ret = kernfs_remove_self(kn);
445
446 kernfs_put(kn);
447 return ret;
448}
449
Greg Kroah-Hartman1b18dc22013-08-21 16:28:26 -0700450void sysfs_remove_files(struct kobject *kobj, const struct attribute **ptr)
Andi Kleen1c205ae2010-01-05 12:48:01 +0100451{
452 int i;
453 for (i = 0; ptr[i]; i++)
454 sysfs_remove_file(kobj, ptr[i]);
455}
Greg Kroah-Hartman1b866752013-08-21 16:17:47 -0700456EXPORT_SYMBOL_GPL(sysfs_remove_files);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457
Alan Sterndfa87c82007-02-20 15:02:44 -0500458/**
459 * sysfs_remove_file_from_group - remove an attribute file from a group.
460 * @kobj: object we're acting for.
461 * @attr: attribute descriptor.
462 * @group: group name.
463 */
464void sysfs_remove_file_from_group(struct kobject *kobj,
465 const struct attribute *attr, const char *group)
466{
Tejun Heo324a56e2013-12-11 14:11:53 -0500467 struct kernfs_node *parent;
Alan Sterndfa87c82007-02-20 15:02:44 -0500468
Tejun Heoccf73cf2013-11-28 14:54:30 -0500469 if (group) {
Tejun Heo324a56e2013-12-11 14:11:53 -0500470 parent = kernfs_find_and_get(kobj->sd, group);
Tejun Heoccf73cf2013-11-28 14:54:30 -0500471 } else {
Tejun Heo324a56e2013-12-11 14:11:53 -0500472 parent = kobj->sd;
473 kernfs_get(parent);
Tejun Heoccf73cf2013-11-28 14:54:30 -0500474 }
475
Tejun Heo324a56e2013-12-11 14:11:53 -0500476 if (parent) {
477 kernfs_remove_by_name(parent, attr->name);
478 kernfs_put(parent);
Alan Sterndfa87c82007-02-20 15:02:44 -0500479 }
480}
481EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
482
Tejun Heo3124eb12013-10-01 17:42:09 -0400483/**
484 * sysfs_create_bin_file - create binary file for object.
485 * @kobj: object.
486 * @attr: attribute descriptor.
487 */
488int sysfs_create_bin_file(struct kobject *kobj,
489 const struct bin_attribute *attr)
490{
491 BUG_ON(!kobj || !kobj->sd || !attr);
492
Tejun Heoa7dc66d2013-11-28 14:54:23 -0500493 return sysfs_add_file(kobj->sd, &attr->attr, true);
Tejun Heo3124eb12013-10-01 17:42:09 -0400494}
495EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
496
497/**
498 * sysfs_remove_bin_file - remove binary file for object.
499 * @kobj: object.
500 * @attr: attribute descriptor.
501 */
502void sysfs_remove_bin_file(struct kobject *kobj,
503 const struct bin_attribute *attr)
504{
Tejun Heo879f40d2013-11-23 17:21:49 -0500505 kernfs_remove_by_name(kobj->sd, attr->attr.name);
Tejun Heo3124eb12013-10-01 17:42:09 -0400506}
507EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);